Liquid dispensing device

Abstract

To provide a liquid discharge device capable of downsizing, and improving accuracy of liquid discharge.SOLUTION: A liquid discharge device comprises a substrate unit which is electrically connected to a print head by fitting a first connector and a second connector, and which has a wiring board containing a plurality of rigid members and a flexible member. A first rigid member laminated on a first plane of a first region of the flexible member and a second rigid member laminated on a first plane of a second region of the flexible member are positioned so as to face each other. A third rigid member laminated on a first plane of a third region of the flexible member is positioned so that a normal direction of a third surface crosses a normal direction of a first surface and a second surface. Further in the liquid discharge device, the second connector is provided on a fourth rigid member laminated on a second plane of a third region of the flexible member, and sizes of the third rigid member and the fourth rigid member are smaller than a size of the print head when viewing a first discharge part from the first connector.SELECTED DRAWING: Figure 30

Description

Technical Field

[0001] The present invention relates to a liquid ejection device.

Background Art

[0002] More than half a century has passed since the invention of liquid ejection technology using a piezoelectric element, and liquid ejection devices using such technology are utilized in a wide range of fields such as inkjet printers and color filter manufacturing devices. These days, with the basic technology of such liquid ejection technology established, the central market requirement for liquid ejection devices is to improve the productivity of products produced using the liquid ejection devices. In response to such market requirements, the focus of technological development of liquid ejection technology is the multi-nozzling of nozzles through which the liquid ejection device ejects liquid, an increase in the ejection amount of ink ejected by the liquid ejection device per unit time, and the like.

[0003] Patent Document 1 discloses a printing device (liquid ejection device) in which a plurality of heads having many nozzles are used to increase the ejection amount per unit time in order to enhance the productivity of products, the printing device having a plurality of head units (liquid ejection heads) provided in a housing, a plurality of drive circuits that supply drive signals to the head units, and a cooling mechanism that cools the drive circuits.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, although the liquid ejection device described in Patent Document 1 can improve productivity, it is not sufficient from the viewpoints of miniaturization of the liquid ejection device and improvement of liquid ejection accuracy, and there is room for improvement. [Means for solving the problem]

[0006] One embodiment of the liquid dispensing device according to the present invention is: A print head that ejects liquid, A circuit board unit electrically connected to the print head, Equipped with, The aforementioned print head is A first discharge unit includes a first piezoelectric element that is displaced in response to a first drive signal, and discharges liquid due to the displacement of the first piezoelectric element, A first connector electrically connected to the aforementioned circuit board unit, It has, The aforementioned circuit board unit is A second connector that, when mated with the first connector, electrically connects to the print head, A wiring board on which multiple circuit components, including the second connector, are provided, It has, The wiring board is a rigid-flexible substrate comprising a plurality of rigid members on which the plurality of circuit components are provided, and a flexible member that is more flexible than the plurality of rigid members, The flexible member has a first surface, a second surface opposite to the first surface, and a first region, a second region Including the third region, the fourth region, and the fifth region, The fourth region is located between the first region and the second region. The fifth region is located between the second region and the third region. The plurality of rigid members include a first rigid member, a second rigid member, a third rigid member, and a fourth rigid member. The first rigid member includes a first surface, and is laminated in the first region on the first surface such that the first surface extends along the first surface. The second rigid member includes a second surface, and is laminated to the first surface in the second region such that the second surface extends along the first surface. The third rigid member includes a third surface, and is laminated on the first surface of the third region such that the third surface extends along the first surface. The fourth rigid member includes a fourth surface, and is laminated on the second surface of the third region such that the fourth surface extends along the second surface. The first rigid member and the second rigid member are positioned such that the first surface and the second surface face each other when the flexible member bends in the fourth region. The third rigid member is positioned such that, as the flexible member bends in the fifth region, the normal direction of the third surface intersects with both the normal direction of the first surface and the normal direction of the second surface. The second connector is provided on the fourth rigid member, When viewed along the direction from the third rigid member toward the fourth rigid member, the sizes of the third rigid member and the fourth rigid member are smaller than the size of the print head when viewed along the direction from the first connector toward the first ejection section. [Brief explanation of the drawing]

[0007] [Figure 1] This is a diagram showing the schematic configuration of a liquid dispensing device. [Figure 2] This figure shows an example of the functional configuration of a head unit. [Figure 3] This diagram shows the configuration of the drive signal output circuit. [Figure 4] This figure shows an example of the signal waveforms for the drive signals COMA and COMB. [Figure 5] This figure shows an example of the signal waveform of the drive signal VOUT. [Figure 6] This diagram shows the functional configuration of the drive signal selection circuit. [Figure 7] This figure shows an example of the content decoded by the decoder. [Figure 8] This is a diagram showing the configuration of the selection circuit. [Figure 9] This is a diagram illustrating the operation of the drive signal selection circuit. [Figure 10] It is a side view showing the structure of a carriage equipped with a head unit. [Figure 11] It is a perspective view showing the peripheral structure of a carriage equipped with a head unit. [Figure 12] It is an exploded perspective view showing an example of the structure of a liquid ejection module. [Figure 13] It is a perspective view showing an example of the internal structure of a print head. [Figure 14] It is an exploded perspective view of a print head. [Figure 15] It is a diagram showing an example of the configuration of a discharge portion included in a discharge module. [Figure 16] It is a diagram showing the planar structure of a drive circuit board. [Figure 17] It is a cross-sectional view when the drive circuit board is cut along line A-a shown in FIG. 16. [Figure 18] It is a cross-sectional view when the drive circuit board is cut along line B-b shown in FIG. 16. [Figure 19] It is a diagram showing an example of the structure of a drive circuit board having a substantially box shape. [Figure 20] It is a diagram showing an example of component arrangement in a drive circuit board in a deployed state. [Figure 21] It is a diagram showing an example of a wiring pattern through which voltage signals VHV, VMV, and VDD propagate. [Figure 22] It is a diagram showing an example of a wiring pattern through which a drive signal COM and a reference voltage signal VBS propagate. [Figure 23] It is a diagram showing an example of component arrangement in a drive circuit board in an assembled state. [Figure 24] It is a diagram showing an example of component arrangement in a drive circuit board in an assembled state. [Figure 25] It is a plan view showing an example of the structure of an intermediate substrate. [Figure 26] It is a side view showing an example of the structure of an intermediate substrate. [Figure 27] It is a view of a drive circuit module seen from the -x2 side along the x2 axis. [Figure 28]This is a view of the drive circuit module along the x2 axis, from the +x2 side. [Figure 29] This is a view of the drive circuit module along the y2 axis, from the -y2 side. [Figure 30] This is a view of the drive circuit module along the z2 axis, from the +z2 side. [Figure 31] This diagram shows a schematic configuration of a modified liquid dispensing device. [Figure 32] This is an exploded perspective view showing an example of the structure of a modified liquid dispensing module. [Figure 33] This figure shows an example of component placement on a drive circuit board in a modified, unfolded state. [Modes for carrying out the invention]

[0008] Preferred embodiments of the present invention will be described below with reference to the drawings. The drawings used are for illustrative purposes only. The embodiments described below are not intended to unduly limit the scope of the present invention as described in the claims. Furthermore, not all of the configurations described below are essential components of the present invention.

[0009] 1. Functional configuration of the liquid dispensing device 1.1 Functional configuration of the liquid dispensing device Figure 1 shows a schematic configuration of the liquid dispensing device 1. The liquid dispensing device 1 of this embodiment is a so-called inkjet printer that forms a desired image on the surface of a medium P by dispensing ink, which is an example of a liquid, at a desired timing onto the medium P being transported. Here, in the following description, the direction in which the medium P is transported may be referred to as the transport direction.

[0010] As shown in Figure 1, the liquid dispensing device 1 comprises a control unit 2, a head unit 3, a transport motor 4, transport rollers 5, a carriage motor 6, a carriage guide shaft 7, a carriage 8, and a liquid container 9.

[0011] The control unit 2 generates control signals to control each element of the liquid dispensing device 1 based on image data DATA supplied from an external device such as a host computer (not shown) located outside the liquid dispensing device 1, and outputs them to the corresponding configuration. The control unit 2 also generates voltage signals VDC used for power supply voltages, etc., for each part of the liquid dispensing device 1 from the commercial AC voltage VAC supplied to the liquid dispensing device 1, and supplies them to each part of the liquid dispensing device 1.

[0012] Specifically, the control unit 2 generates a transport control signal Ctrl-T as a control signal to control each element of the liquid dispensing device 1, and outputs it to the transport motor 4. The transport motor 4 is driven based on the input transport control signal Ctrl-T. The transport roller 5 rotates in conjunction with the drive of the transport motor 4. The medium P is then transported along the transport direction by the driving force generated by the rotation of the transport roller 5. In other words, the transport motor 4 and the transport roller 5 transport the medium P in accordance with the transport control signal Ctrl-T output by the control unit 2.

[0013] Furthermore, the control unit 2 generates a carriage control signal Ctrl-C as a control signal to control each element of the liquid dispensing device 1, and outputs it to the carriage motor 6. The carriage motor 6 is driven based on the input carriage control signal Ctrl-C. The driving force generated by the driving of the carriage motor 6 is transmitted to the carriage 8, which is supported by the carriage guide shaft 7, via a timing belt (not shown). The carriage guide shaft 7 extends along a direction intersecting the conveying direction and supports the carriage 8. The carriage 8, supported by the carriage guide shaft 7, moves along the carriage guide shaft 7 due to the driving force generated by the driving of the carriage motor 6. In other words, the carriage motor 6 and the carriage The carriage guide axis 7 moves the carriage 8 along the carriage guide axis 7 in response to the carriage control signal Ctrl-C output by the control unit 2.

[0014] Furthermore, the control unit 2 generates a print data signal pDATA as a control signal to control each element of the liquid ejection device 1 and outputs it to the head unit 3. The head unit 3 has an ejection control module 10 and a plurality of liquid ejection modules 20. Each of the plurality of liquid ejection modules 20 has a drive circuit module 50 and a print head 30. In other words, the head unit 3 has multiple sets of drive circuit module 50 and print head 30. Such a head unit 3 is mounted on a carriage 8 and moves as the carriage 8 moves along the carriage guide axis 7.

[0015] The print data signal pDATA output by the control unit 2 is input to the ejection control module 10. Based on the input print data signal pDATA, the ejection control module 10 generates a control signal to control the operation of each of the multiple liquid ejection modules 20 and outputs it to the corresponding liquid ejection module 20. The control signal output by the ejection control module 10 is input to the corresponding drive circuit module 50. The drive circuit module 50 is electrically connected to the corresponding print head 30 and drives the print head 30 so that the amount of ink specified by the input control signal is ejected at the timing specified by the control signal. As a result, the print head 30 ejects a predetermined amount of ink at a predetermined timing. In other words, the head unit 3 ejects a predetermined amount of ink from the print head 30 at a predetermined timing in accordance with the print data signal pDATA output by the control unit 2.

[0016] The liquid container 9 stores the ink ejected from the print head 30. The ink stored in this liquid container 9 is supplied to the print head 30 via a tube (not shown) or the like. Examples of such liquid containers 9 include ink cartridges, pouch-shaped ink packs made of flexible film, and ink tanks that can be refilled.

[0017] As described above, the liquid ejection device 1 is controlled by the control unit 2, which controls the transport of the medium P, the movement of the carriage 8, and the timing of ink ejection from the print head 30 mounted on the carriage 8. This allows the ink to land at the desired position on the medium P, and as a result, the desired image is formed on the medium P.

[0018] 1.2 Functional Configuration of the Head Unit Next, the details of the functional configuration of the head unit 3 of the liquid dispensing device 1 will be described. Figure 2 is a diagram showing an example of the functional configuration of the head unit 3. As shown in Figure 2, the head unit 3 has a dispensing control module 10 and a plurality of liquid dispensing modules 20. Here, although the plurality of liquid dispensing modules 20 of the head unit 3 all have the same configuration, when describing the plurality of liquid dispensing modules 20 separately, they may be referred to as liquid dispensing modules 20-1 to 20-n. That is, the head unit 3 shown in Figure 2 may be described as having n liquid dispensing modules 20-1 to 20-n.

[0019] Furthermore, Figure 2 illustrates the configuration of the head unit 3, as well as some of the components included in the control unit 2, namely the main control circuit 16 and the power supply voltage output circuit 18. The main control circuit 16 included in the control unit 2 includes processing circuits such as a CPU (Central Processing Unit) and an FPGA (Field Programmable Gate Array), and storage circuits such as semiconductor memory. The main control circuit 16 performs predetermined signal processing on image data DATA supplied from an external device such as a host computer (not shown) located outside the liquid discharge device 1, and then displays the image data. A print data signal pDATA is generated and output to the ejection control module 10.

[0020] The power supply voltage output circuit 18 includes an AC / DC converter such as a flyback circuit and a DC / DC converter such as a step-down circuit or a step-up circuit. The power supply voltage output circuit 18 generates voltage signals VHV, which is a DC voltage signal with a voltage value of 42V, and voltage signals VMV, which is a DC voltage signal with a voltage value of 24V, as voltage signals VDC from the commercial voltage VAC input from outside the liquid dispensing device 1, and outputs them to the dispensing control module 10. Note that the voltage values ​​of voltage signals VHV and VMV are not limited to 42V and 24V. In addition, the power supply voltage output circuit 18 may output a DC voltage signal with a different voltage value as voltage signal VDC instead of or in addition to voltage signals VHV and VMV.

[0021] The dispensing control module 10 operates using the voltage signals VHV,VMV output by the power supply voltage output circuit 18, or the DC voltage signal generated from the voltage signals VHV,VMV, as the power supply voltage. Based on the print data signal pDATA output by the control unit 2, the dispensing control module 10 generates control signals to control the operation of the n liquid dispensing modules 20 and outputs them to the corresponding liquid dispensing modules 20.

[0022] The ejection control module 10 includes a head control circuit 12 and a cooling fan drive circuit 14. The print data signal pDATA is input to the head control circuit 12 included in the ejection control module 10. Based on the input print data signal pDATA, the head control circuit 12 generates and outputs a clock signal SCK that is input in common to the n liquid ejection modules 20, differential print data signals Dp1 to Dpn corresponding to each of the n liquid ejection modules 20, and differential drive data signals Dd1 to Ddn corresponding to each of the n liquid ejection modules 20.

[0023] Specifically, the print data signal pDATA is a differential signal generated based on image data DATA, and serially includes a clock signal SCK, differential print data signals Dp1~Dpn, and differential drive data signals Dd1~Ddn. The head control circuit 12 deserializes and restores the input print data signal pDATA to generate a clock signal SCK that is commonly input to the n liquid ejection modules 20. The head control circuit 12 also deserializes the input print data signal pDATA to generate differential print data signals Dp1~Dpn and differential drive data signals Dd1~Ddn, which correspond to each of the n liquid ejection modules 20. The head control circuit 12 then outputs the generated clock signal SCK, differential print data signals Dp1~Dpn, and differential drive data signals Dd1~Ddn to the corresponding liquid ejection modules 20.

[0024] In the following explanation, we will assume that the differential printing data signal Dp1 and the differential drive data signal Dd1 correspond to the liquid ejection module 20-1, and that the differential printing data signal Dpn and the differential drive data signal Ddn correspond to the liquid ejection module 20-n. Specifically, we will assume that the liquid ejection module 20-1 receives the clock signal SCK, the differential printing data signal Dp1, and the differential drive data signal Dd1, and that the liquid ejection module 20-n receives the clock signal SCK, the differential printing data signal Dpn, and the differential drive data signal Ddn. Furthermore, we will assume that the liquid ejection module 20 receives the clock signal SCK, the differential printing data signal Dp, and the differential drive data signal Dd.

[0025] Furthermore, the head control circuit 12 generates a fan control signal Fc to control the operation of the cooling fan drive circuit 14 and outputs it to the cooling fan drive circuit 14. In addition to the fan control signal Fc, the cooling fan drive circuit 14 receives a voltage signal VMV. Based on the input fan control signal Fc, the cooling fan drive circuit 14 outputs the voltage signal VMV to the fan drive signals Fp1~Fpn. The cooling fan drive circuit 14 switches whether or not to output the voltage signal VMV as fan drive signals Fp1 to Fpn, and the conduction state of each of the n switch circuits is switched by the input fan control signal Fc.

[0026] The fan drive signals Fp1 to Fpn output by the cooling fan drive circuit 14 are output to the corresponding liquid discharge modules 20. In the following explanation, it will be assumed that fan drive signal Fp1 corresponds to liquid discharge module 20-1, and fan drive signal Fpn corresponds to liquid discharge module 20-n. That is, fan drive signal Fp1 is input to liquid discharge module 20-1, and fan drive signal Fpn is input to liquid discharge module 20-n. Furthermore, it will be assumed that fan drive signal Fp is input to liquid discharge module 20.

[0027] The cooling fan drive circuit 14 may also convert the voltage signal VMV to a predetermined voltage value based on the input fan control signal Fc, and output the converted signal as fan drive signals Fp1 to Fpn.

[0028] Furthermore, the discharge control module 10 propagates the voltage signals VHV and VMV supplied from the power supply voltage output circuit 18 and supplies them to each of the liquid discharge modules 20-1 to 20-n.

[0029] The liquid ejection module 20-1 receives the clock signal SCK, differential printing data signal Dp1, differential drive data signal Dd1, fan drive signal Fp1, and voltage signals VHV,VMV, which are output by the ejection control module 10. The liquid ejection module 20-1 operates using the voltage signals VHV,VMV, or a DC voltage generated from the voltage signals VHV,VMV, as the power supply voltage, and ejects the amount of ink specified by the differential printing data signal Dp1 and the differential drive data signal Dd1 onto the medium P at the timings specified by the differential printing data signal Dp1 and the differential drive data signal Dd1.

[0030] The liquid ejection module 20-1 includes a drive circuit module 50 and a print head 30. The drive circuit module 50 also includes an ejection control circuit 51, drive signal output circuits 52a-1 to 52a-m, 52b-1 to 52b-m, a capacitor 53, an abnormality detection circuit 54, an abnormality notification circuit 55, a temperature detection circuit 56, a voltage conversion circuit 58, and a cooling fan 59.

[0031] The ejection control circuit 51 receives a clock signal SCK, a differential print data signal Dp1, and a differential drive data signal Dd1 as inputs. The ejection control circuit 51 then analyzes the input differential print data signal Dp1 and differential drive data signal Dd1 to generate and output a differential print data signal Dpt that controls the operation of the print head 30, base drive signals dA1 to dAm which form the basis of the drive signals COMA1 to COMAm described later, and base drive signals dB1 to dBm which form the basis of the drive signals COMB1 to COMBm described later. Such an ejection control circuit 51 is configured to include an FPGA with a circuit for analyzing the input differential print data signal Dp1 and differential drive data signal Dd1.

[0032] In other words, the drive circuit module 50 has an FPGA on which an ejection control circuit 51 is implemented that receives a differential print data signal Dp1 and a differential drive data signal Dd1 as inputs and outputs a differential print data signal Dpt that controls the operation of the print head 30 based on the input differential print data signal Dp1 and differential drive data signal Dd1, and base drive signals dA1~dAm,dB1~dBm that are the basis for drive signals COMA1~COMAm,COMB1~COMBm.

[0033] Specifically, the ejection control circuit 51 analyzes the input differential print data signal Dp1 based on the input clock signal SCK. The ejection control circuit 51 then generates a differential print data signal Dpt corresponding to the analysis result of the differential print data signal Dp1 and outputs it to the print head 30. At this time, the ejection control circuit 51 may output the differential print data signal Dp1 as the differential print data signal Dpt, or it may output a signal obtained by applying predetermined signal processing to the differential print data signal Dp1 as the differential print data signal Dpt. Furthermore, the ejection control circuit 51 may output a signal containing predetermined information read from a storage circuit (not shown) as the differential print data signal Dpt according to the analysis result of the differential print data signal Dp1.

[0034] Furthermore, the ejection control circuit 51 analyzes and reconstructs the input differential drive data signal Dd1 into a single-ended signal based on the input clock signal SCK. The ejection control circuit 51 then generates base drive signals dA1~dAm, dB1~dBm according to the analysis results and outputs them to the corresponding drive signal output circuits 52a-1~52a-m, 52b-1~52b-m. Alternatively, the ejection control circuit 51 may read information held in a memory circuit (not shown) based on the analysis results of the single-ended signal reconstructed from the differential drive data signal Dd1, generate base drive signals dA1~dAm, dB1~dBm including the read information, and output them to the corresponding drive signal output circuits 52a-1~52a-m, 52b-1~52b-m. Furthermore, the ejection control circuit 51 may generate a single-ended signal by restoring the differential drive data signal Dd1, and generate the base drive signals dA1~dAm and dB1~dBm by deserializing the single-ended signal, and output them to the corresponding drive signal output circuits 52a-1~52a-m and 52b-1~52b-m.

[0035] Here, we will explain assuming that the base drive signal dA1 output by the discharge control circuit 51 corresponds to the drive signal output circuit 52a-1, and the base drive signal dAm output by the discharge control circuit 51 corresponds to the drive signal output circuit 52a-m. Similarly, we will explain assuming that the base drive signal dB1 output by the discharge control circuit 51 corresponds to the drive signal output circuit 52b-1, and the base drive signal dBm output by the discharge control circuit 51 corresponds to the drive signal output circuit 52b-m. That is, the base drive signal dA1 is input to the drive signal output circuit 52a-1, the base drive signal dAm is input to the drive signal output circuit 52a-m, the base drive signal dB1 is input to the drive signal output circuit 52b-1, and the base drive signal dBm is input to the drive signal output circuit 52b-m.

[0036] The drive signal output circuit 52a-1 generates the drive signal COMA1 by digital-to-analog conversion of the input base drive signal dA1 and class D amplification, and outputs it to the print head 30. The drive signal output circuit 52b-1 generates the drive signal COMB1 by digital-to-analog conversion of the input base drive signal dB1 and class D amplification, and outputs it to the print head 30. Similarly, the drive signal output circuits 52a-m generate the drive signal COMAm by digital-to-analog conversion of the input base drive signal dAm and class D amplification, and output it to the print head 30. The drive signal output circuits 52b-m generate the drive signal COMBm by digital-to-analog conversion of the input base drive signal dBm and class D amplification, and output it to the print head 30.

[0037] In other words, each of the drive signal output circuits 52a-1 to 52a-m and 52b-1 to 52b-m converts the input base drive signals dA1 to dAm and dB1 to dBm from digital to analog and generates drive signals COMA1 to COMAm and COMB1 to COMBm by performing a Class D amplification, which are then output to the print head 30. To put it another way, each of the drive signal output circuits 52a-1 to 52a-m and 52b-1 to 52b-m includes a Class D amplification circuit, with drive signal output circuits 52a-1 to 52a-m outputting drive signals COMA1 to COMAm, and drive signal output circuits 52b-1 to 52b-m outputting drive signals COMB1 to COMBm. At this time, the base drive signals dA1 to dAm and dB1 to dBm output by the ejection control circuit 51 These are the underlying signals for the drive signals COMA1~COMAm and COMB1~COMBm output by the drive signal output circuits 52a-1~52a-m and 52b-1~52b-m, respectively, and are signals that define the signal waveforms of the drive signals COMA1~COMAm and COMB1~COMBm.

[0038] Here, it was explained that the drive signal output circuits 52a-1~52a-m and 52b-1~52b-m generate drive signals COMA1~COMAm and COMB1~COMBm by class D amplification of the signal waveform defined by the base drive signals dA1~dAm and dB1~dBm. However, the drive signal output circuits 52a-1~52a-m and 52b-1~52b-m may also generate drive signals COMA1~COMAm and COMB1~COMBm by class A amplification, class B amplification, or class AB amplification of the signal waveform defined by the base drive signals dA1~dAm and dB1~dBm. However, the drive signal output circuits 52a-1~52a-m and 52b-1~52b-m consume a lot of power and therefore generate a lot of heat. These drive signal output circuits 52a-1 to 52a-m and 52b-1 to 52b-m are required to generate drive signals COMA1 to COMAm and COMB1 to COMBm with high efficiency from the perspective of reducing power consumption and suppressing heat generation.

[0039] From this perspective, it is preferable that the drive signal output circuits 52a-1 to 52a-m and 52b-1 to 52b-m include a Class D amplifier capable of efficiently amplifying the signal waveform defined by the base drive signals dA1 to dAm and dB1 to dBm. Details of the configuration of the drive signal output circuits 52a-1 to 52a-m and 52b-1 to 52b-m, which include a Class D amplifier, will be described later.

[0040] Furthermore, the drive signal output circuits 52a-1 to 52a-m and 52b-1 to 52b-m each generate and output a reference voltage signal VBS. At this time, the drive circuit module 50 stabilizes the voltage value of the reference voltage signal VBS output by the drive signal output circuit 52a-1 using a capacitor 53. In other words, the drive circuit module 50 has a capacitor 53 to reduce fluctuations in the voltage value of the reference voltage signal VBS. After the voltage value of the reference voltage signal VBS is stabilized by the capacitor 53, it is branched and output to the print head 30, and the wiring through which the reference voltage signals VBS output by the drive signal output circuits 52a-2 to 52a-m and 52b-1 to 52b-m propagate is opened. In other words, the drive circuit module 50 outputs the reference voltage signal VBS output by the drive signal output circuit 52a-1 to the print head 30, but does not output the reference voltage signals VBS output by the drive signal output circuits 52a-2 to 52a-m and 52b-1 to 52b-m to the print head 30.

[0041] The reference voltage signal VBS functions as the reference potential for driving the piezoelectric element 60, which will be described later, located in the print head 30. If the voltage value of the reference voltage signal VBS, which functions as such a reference potential, fluctuates, the driving characteristics of the piezoelectric element 60 will change. In contrast, by making the reference voltage signal VBS supplied to the piezoelectric element 60 solely the reference voltage signal VBS output by the drive signal output circuit 52a-1, even if there are variations in the voltage values ​​of the reference voltage signals VBS output by the drive signal output circuits 52a-1 to 52a-m and 52b-1 to 52b-m due to circuit variations, the risk of fluctuations in the voltage value of the reference voltage signal VBS supplied to the piezoelectric element 60 is reduced. This improves the driving accuracy of the piezoelectric element 60.

[0042] Furthermore, the reference voltage signal VBS output from the drive circuit module 50 that is input to the print head 30 can be any reference voltage signal VBS output by any one of the drive signal output circuits 52a-1 to 52a-m or 52b-1 to 52b-m, and is not limited to the reference voltage signal VBS output by drive signal output circuit 52a-1.

[0043] Here, the drive signal output circuits 52a-1 to 52a-m and 52b-1 to 52b-m are identical in configuration, differing only in the input and output signals. Therefore, in the following explanation, when it is not necessary to distinguish between the drive signal output circuits 52a-1 to 52a-m and 52b-1 to 52b-m, they may simply be referred to as drive signal output circuit 52. In this case, the explanation will proceed assuming that the base drive signal dO is input to drive signal output circuit 52 and that drive signal output circuit 52 outputs the drive signal COM.

[0044] The temperature detection circuit 56 acquires the ambient temperature of the drive circuit module 50. Here, the ambient temperature of the drive circuit module 50 does not refer to the temperature of the components of the drive circuit module 50 themselves, but rather includes the ambient temperature of the drive circuit module 50 that changes as the temperature of those components rises. The temperature detection circuit 56 then generates a temperature information signal Tt that includes temperature information corresponding to the acquired ambient temperature and outputs it to the head control circuit 12.

[0045] The head control circuit 12 estimates the temperature of the drive circuit module 50 based on the input temperature information signal Tt. Then, the head control circuit 12 corrects the clock signal SCK, differential print data signals Dp1~Dpn, and differential drive data signals Dd1~Ddn according to the estimated temperature of the drive circuit module 50, and outputs the corrected clock signal SCK, differential print data signals Dp1~Dpn, and differential drive data signals Dd1~Ddn. In other words, the head control circuit 12 controls the operation of the drive signal output circuits 52a-1~52a-m, 52b-1~52b-m, and the print head 30 based on the temperature information signal Tt corresponding to the ambient temperature acquired by the temperature detection circuit 56.

[0046] Furthermore, if the estimated temperature of the drive circuit module 50 is above a predetermined threshold, the head control circuit 12 determines that a temperature abnormality has occurred or is likely to occur in the drive circuit module 50. In this case, the head control circuit 12 may generate a clock signal SCK, differential print data signals Dp1 to Dpn, and differential drive data signals Dd1 to Ddn to stop the operation of the drive circuit module 50 and output them to the drive circuit module 50. In other words, the head control circuit 12 may stop the operation of the drive signal output circuits 52a-1 to 52a-m, 52b-1 to 52b-m, and the print head 30 based on the temperature information signal Tt corresponding to the ambient temperature acquired by the temperature detection circuit 56.

[0047] Furthermore, the head control circuit 12 may inform the user of information corresponding to the estimated temperature of the drive circuit module 50, which is the temperature information acquired by the temperature detection circuit 56, via a notification unit (not shown), such as a display. In other words, the head control circuit 12 may inform the user of information based on the temperature information signal Tt corresponding to the ambient temperature acquired by the temperature detection circuit 56.

[0048] As the temperature detection circuit 56 that detects the ambient temperature, which is the ambient temperature inside the drive circuit module 50, for example, a thermistor element or an IC temperature sensor element can be used. That is, the temperature information signal Tt output by the temperature detection circuit 56 may include temperature information indicating the temperature of the drive circuit module 50 itself, or it may include a voltage value or current value that changes according to the temperature of the drive circuit module 50 as temperature information.

[0049] Furthermore, the drive circuit module 50 receives voltage signals VHV and VMV propagated from the ejection control module 10. Voltage signal VHV propagates within the drive circuit module 50 and is supplied to various components of the drive circuit module 50, as well as to the print head 30. Voltage signal VMV propagates within the drive circuit module 50 and is supplied to various components of the drive circuit module 50, as well as to the voltage conversion circuit 58. The voltage conversion circuit 58 generates and outputs voltage signal VDD by stepping down the input voltage signal VMV. Voltage signal VDD output by the voltage conversion circuit 58 is used as the power supply voltage for various circuits of the drive circuit module 50, as well as to the print head 30. It is supplied. Such a voltage signal VDD is a DC voltage, such as 5V or 3.3V.

[0050] Furthermore, the voltage signal VDD output by the voltage conversion circuit 58 is not limited to one; the voltage conversion circuit 58 may output multiple voltage signals VDD with different voltage values. Also, the voltage signal VMV may be supplied to the print head 30 together with the voltage signals VHV and VDD.

[0051] The abnormality detection circuit 54 detects an abnormality occurring in the drive circuit module 50 and generates an abnormality information signal Te and an abnormality notification signal De according to the detection result. Such an abnormality detection circuit 54 is configured to include a comparator, for example, which compares whether the detected object is above a predetermined threshold.

[0052] The abnormal information signal Te output by the abnormal detection circuit 54 is input to the head control circuit 12. If the input abnormal information signal Te contains information indicating an abnormality in the drive circuit module 50, the head control circuit 12 generates a clock signal SCK, differential print data signals Dp1 to Dpn, and differential drive data signals Dd1 to Ddn to stop the operation of the drive circuit module 50, and outputs them to the drive circuit module 50. As a result, the operation of the drive circuit module 50 stops.

[0053] Furthermore, the abnormality notification signal De output by the abnormality detection circuit 54 is input to the abnormality notification circuit 55. The abnormality notification circuit 55 includes, for example, a light-emitting element such as a light-emitting diode. Based on the input abnormality notification signal De, the abnormality notification circuit 55 notifies the user whether or not an abnormality has occurred in the drive circuit module 50 by turning on, turning off, or blinking the light-emitting element.

[0054] Here, we will describe an example of the operation of the abnormality detection circuit 54 and the abnormality notification circuit 55.

[0055] For example, if the abnormality detection circuit 54 detects that the voltage value of the voltage signal VHV is lower than the normal value, the abnormality detection circuit 54 determines that the voltage value of the voltage signal VHV is not normal, generates an abnormality notification signal De to alert the user, and outputs it to the abnormality notification circuit 55. Based on the input abnormality notification signal De, the abnormality notification circuit 55 flashes a light-emitting element to notify that the voltage value of the voltage signal VHV has decreased.

[0056] Subsequently, if the voltage value of the voltage signal VHV decreases further and the abnormality detection circuit 54 detects that the voltage value of the voltage signal VHV has fallen below a predetermined threshold, the abnormality detection circuit 54 determines that the voltage value of the voltage signal VHV is abnormal, generates an abnormality notification signal De to notify the user of the abnormality, and outputs it to the abnormality notification circuit 55. Based on the input abnormality notification signal De, the abnormality notification circuit 55 lights up a light-emitting element to notify that an abnormality has occurred in the voltage value of the voltage signal VHV. At this time, the abnormality detection circuit 54 generates an abnormality information signal Te, which contains abnormality information indicating that there is an abnormality in the drive circuit module 50 and that the voltage value of the voltage signal VHV is abnormal, and outputs it to the head control circuit 12.

[0057] Furthermore, for example, if the abnormality detection circuit 54 detects that the voltage value of the voltage signal VDD, which is used for the power supply voltage of the FPGA constituting the discharge control circuit 51, has fallen below the normal value, the abnormality detection circuit 54 determines that the voltage value of the voltage signal VDD is not normal, generates an abnormality notification signal De to alert the user, and outputs it to the abnormality notification circuit 55. Based on the input abnormality notification signal De, the abnormality notification circuit 55 flashes a light-emitting element to notify that the voltage value of the voltage signal VDD has fallen.

[0058] Subsequently, if the voltage value of the voltage signal VDD decreases further and the abnormality detection circuit 54 detects that the voltage value of the voltage signal VDD has fallen below a predetermined threshold, the abnormality detection circuit 54 will The system determines that the voltage value of the voltage signal VDD is abnormal and generates an abnormality notification signal De to notify the user of the abnormality, which is output to the abnormality notification circuit 55. Based on the input abnormality notification signal De, the abnormality notification circuit 55 lights up a light-emitting element to notify that there is an abnormality in the voltage value of the voltage signal VDD. At this time, the abnormality detection circuit 54 generates an abnormality information signal Te, which contains abnormality information indicating that there is an abnormality in the drive circuit module 50 and that the voltage value of the voltage signal VDD is abnormal, and outputs it to the head control circuit 12.

[0059] Here, the number of light-emitting elements in the abnormality notification circuit 55 is not limited to one. For example, it may have a light-emitting element for notifying whether there is an abnormality in the voltage signal VHV and a light-emitting element for notifying whether there is an abnormality in the voltage signal VDD. Furthermore, if the abnormality notification circuit 55 has multiple light-emitting elements, the presence or absence of an abnormality in the drive circuit module 50 may be notified to the user by a combination of the lighting, extinguishing, and flashing of the multiple light-emitting elements. In addition, in the above description, the abnormality detection circuit 54 was described as detecting whether there is an abnormality in the voltage value of the voltage signal VHV and the voltage value of the voltage signal VDD as examples of detecting whether there is an abnormality in the voltage value of the drive circuit module 50. However, instead of, or in addition to, detecting whether there is an abnormality in the voltage value of the voltage signal VHV and the voltage signal VDD, the abnormality detection circuit 54 may also detect whether there is a heat generation abnormality in the drive circuit module 50 based on the temperature information signal Tt output by the temperature detection circuit 56, or it may detect whether there is a voltage abnormality in the voltage signal VMV.

[0060] The cooling fan 59 receives a fan drive signal Fp1 output by the cooling fan drive circuit 14. The cooling fan 59 is then driven by the input fan drive signal Fp1, generating airflow around the drive circuit module 50. This airflow generated by the cooling fan 59 cools the drive circuit module 50. The head control circuit 12 may also output a fan control signal Fc based on the temperature information signal Tt output by the temperature detection circuit 56. As a result, the driving state of the cooling fan 59 is controlled according to the temperature of the drive circuit module 50, which is the object to be cooled, based on the temperature detection result by the temperature detection circuit 56. Consequently, the power consumption of the liquid dispensing device 1 is reduced by reducing the risk of increased power consumption due to excessive driving of the cooling fan 59, and the risk of temperature abnormalities occurring in the drive circuit module 50 is also reduced.

[0061] The print head 30 includes a restoration circuit 31 and ejection modules 32-1 to 32-m. The restoration circuit 31 operates using a voltage signal VHV,VDD, or a DC voltage generated from the voltage signal VHV,VDD, as its power supply voltage. The restoration circuit 31 restores the differential print data signal Dpt, a differential signal output by the ejection control circuit 51, to a single-ended signal. Specifically, the restoration circuit 31 receives a clock signal SCK and the differential print data signal Dpt as input. The restoration circuit 31 then restores the differential print data signal Dpt, which is input based on the clock signal SCK, to a single-ended signal, and generates a latch signal LAT, a change signal CH, and print data signals SI1 to SIm by deserializing the restored signal. The restoration circuit 31 then outputs the clock signal SCK, the generated latch signal LAT, change signal CH, and print data signals SI1 to SIm to the corresponding ejection modules 32-1 to 32-m.

[0062] The discharge module 32-1 includes a drive signal selection circuit 200 and a plurality of discharge units 600.

[0063] The drive signal selection circuit 200 receives the latch signal LAT, change signal CH, print data signal SI1, clock signal SCK, and drive signals COMA1 and COMB1 output from the restore circuit 31. The drive signal selection circuit 200 operates using the voltage signal VHV,VDD, or a DC voltage generated from the voltage signal VHV,VDD as the power supply voltage, and selects or deselects the signal waveform included in the drive signal COMA1 based on the print data signal SI1 during the periods defined by the latch signal LAT and the change signal CH. By selecting or deselecting the signal waveform included in the dynamic signal COMB1, the drive signal selection circuit 200 generates and outputs a drive signal VOUT corresponding to each of the multiple discharge units 600. That is, if the discharge module 32-1 has p discharge units 600, the drive signal selection circuit 200 generates p drive signals VOUT corresponding to each of the p discharge units 600 and outputs them to the corresponding discharge unit 600.

[0064] Each of the multiple ejection units 600 includes a piezoelectric element 60. A corresponding drive signal VOUT, output by the drive signal selection circuit 200, is supplied to one end of each piezoelectric element 60. A common reference voltage signal VBS is supplied to the other end of each of the multiple piezoelectric elements 60 included in each of the multiple ejection units 600. The multiple piezoelectric elements 60 included in each of the multiple ejection units 600 are displaced by the potential difference between the drive signal VOUT and the reference voltage signal VBS. An amount of ink corresponding to the displacement of the piezoelectric elements 60 is ejected from the corresponding ejection unit 600. When the ink ejected from the ejection unit 600 lands on the medium P, an image is formed on the medium P. Details of the operation of the drive signal selection circuit 200, which outputs the drive signal VOUT, will be described later.

[0065] Here, the ejection modules 32-2 to 32-m of the print head 30 have the same configuration as ejection module 32-1 and perform the same operation, differing only in the input signals. Therefore, a detailed explanation of ejection modules 32-2 to 32-m is omitted. In other words, each ejection module 32-2 to 32-m includes a drive signal selection circuit 200 and a plurality of ejection units 600. The drive signal selection circuit 200 of each ejection module 32-2 to 32-m selects or deselects the signal waveforms included in the corresponding drive signals COMA2 to COMAm and COMB2 to COMBm based on the corresponding print data signals SI2 to SIm during the period defined by the input latch signal LAT and change signal CH, thereby outputting a drive signal VOUT corresponding to each of the plurality of ejection units 600. As a result, an amount of ink corresponding to the potential difference between the input drive signal VOUT and the reference voltage signal VBS is ejected from each of the multiple ejection units 600 that each of the ejection modules 32-2 to 32-m has.

[0066] In other words, the print head 30 has ejection modules 32-1 to 32-m. Ejection module 32-1 includes a piezoelectric element 60 that is displaced in response to a drive signal VOUT based on drive signals COMA1 and COMB1, and includes an ejection unit 600 that ejects ink by the displacement of the piezoelectric element 60, and a drive signal selection circuit 200 that switches whether or not to supply drive signals COMA1 and COMB1 to the piezoelectric element 60. Ejection module 32-m includes a piezoelectric element 60 that is displaced in response to a drive signal VOUT based on drive signals COMAm and COMBm, and includes an ejection unit 600 that ejects ink by the displacement of the piezoelectric element 60, and a drive signal selection circuit 200 that switches whether or not to supply drive signals COMAm and COMBm to the piezoelectric element 60.

[0067] In the following explanation, when it is not necessary to distinguish between ejection modules 32-1 to 32-m, they may simply be referred to as ejection module 32. Furthermore, it may be explained that ejection module 32 receives the following inputs: print data signals SI (as print data signals SI1 to SIm), drive signals COMA (as drive signals COMA1 to COMAm), and drive signals COMB (as drive signals COMB1 to COMBm). That is, the drive signal selection circuit 200 of ejection module 32, based on the print data signal SI, selects or deselects the signal waveform included in drive signal COMA and the signal waveform included in drive signal COMB during the periods defined by the latch signal LAT and the change signal CH, thereby outputting the drive signal VOUT corresponding to each of the multiple ejection units 600.

[0068] As described above, the liquid ejection module 20-1 has a drive circuit module 50 and a print head 30, and operates based on the clock signal SCK, differential print data signal Dp1, differential drive data signal Dd1, fan drive signal Fp1, and voltage signals VHV,VMV output by the ejection control module 10, ejecting the amount of ink specified by the differential print data signal Dp1 and the differential drive data signal Dd1 onto the medium P at the timing specified by the differential print data signal Dp1 and the differential drive data signal Dd1.

[0069] Here, liquid ejection modules 20-2 to 20-n have the same configuration as liquid ejection module 20-1 and perform the same operation, differing only in the input signals. Therefore, a detailed explanation of liquid ejection modules 20-2 to 20-n is omitted. In other words, each of liquid ejection modules 20-2 to 20-n has a drive circuit module 50 and a print head 30, and operates based on the clock signal SCK, corresponding differential printing data signals Dp2 to Dpn, corresponding differential drive data signals Dd2 to Ddn, corresponding fan drive signals Fp2 to Fpn, and voltage signals VHV, VMV output by the ejection control module 10, ejecting the amount of ink specified by the corresponding differential printing data signals Dp2 to Dpn and the corresponding differential drive data signals Dd2 to Ddn onto the medium P at the timing specified by the corresponding differential printing data signals Dp2 to Dpn and the corresponding differential drive data signals Dd2 to Ddn.

[0070] As described above, the liquid ejection device 1 comprises a print head 30 that ejects ink, a drive circuit module 50 electrically connected to the print head 30, and a control unit 2 and a head control circuit 12 that control the operation of the print head 30 and the drive circuit module 50. The head unit 3, which is included in the liquid ejection device 1 and has an ejection control module 10, a print head 30 and a drive circuit module 50, is driven by voltage signals VHV and VMV input from the control unit 2 as the power supply voltage, and ejects ink at a timing based on the print data signal pDATA, thereby forming an image on the medium P that corresponds to the print data signal pDATA and is an image corresponding to the image data DATA.

[0071] 1.3 Functional Configuration of the Drive Signal Output Circuit Next, the configuration and operation of the drive signal output circuit 52, which outputs a drive signal COM, will be described. Figure 3 shows the configuration of the drive signal output circuit 52. The drive signal output circuit 52 includes an integrated circuit 500, an amplification circuit 550, a demodulation circuit 560, feedback circuits 570, 572, and other electronic components.

[0072] The integrated circuit 500 has multiple terminals, including terminals In, Bst, Hdr, Sw, Gvd, Ldr, Gnd, Vbs, Vfb, and Ifb. The integrated circuit 500 is electrically connected to an externally provided substrate (not shown) via these multiple terminals. The integrated circuit 500 also includes a DAC (Digital to Analog Converter) 511, a modulation circuit 510, a gate drive circuit 520, and a reference power supply circuit 590.

[0073] The reference power supply circuit 590 generates voltage signals DAC_HV and DAC_LV and supplies them to DAC511. DAC511 also receives a digital base drive signal dO, which defines the waveform of the drive signal COM. DAC511 converts the input base drive signal dO into a base drive signal aO, an analog signal representing the voltage between the voltage values ​​of voltage signals DAC_HV and DAC_LV, and outputs it to the modulation circuit 510. That is, the voltage amplitude of the base drive signal aO is defined at its maximum value by voltage signal DAC_HV and at its minimum value by voltage signal DAC_LV. The amplified signal of the base drive signal aO output by DAC511 corresponds to the drive signal COM. In other words, the base drive signal aO corresponds to the target signal before amplification of the drive signal COM, and the base drive signals dO and aO define the waveform of the drive signal COM.

[0074] The modulation circuit 510 generates a modulated signal Ms by modulating the base drive signal aO and outputs it to the gate drive circuit 520. The modulation circuit 510 includes adders 512, 513, a comparator 514, an inverter 515, an integral attenuator 516, and an attenuator 517.

[0075] The integrating attenuator 516 attenuates and integrates the drive signal COM input via terminal Vfb, and outputs it to the negative input terminal of the adder 512. The base drive signal aO is input to the positive input terminal of the adder 512. The adder 512 then outputs the voltage obtained by subtracting the voltage input to the negative input terminal from the voltage input to the positive input terminal and integrating it to the positive input terminal of the adder 513.

[0076] The attenuator 517 outputs a voltage obtained by attenuating the high-frequency component of the drive signal COM input via terminal Ifb to the negative input terminal of the adder 513. The voltage output from adder 512 is input to the positive input terminal of adder 513. The adder 513 then generates a voltage signal Os by subtracting the voltage input to the negative input terminal from the voltage input to the positive input terminal and outputs it to the comparator 514.

[0077] The comparator 514 outputs a modulated signal Ms, which is obtained by pulse modulating the voltage signal Os input from the adder 513. Specifically, the comparator 514 generates and outputs a modulated signal Ms that becomes H level when the voltage value of the voltage signal Os input from the adder 513 rises above a predetermined threshold Vth1, and becomes L level when the voltage value of the voltage signal Os falls below a predetermined threshold Vth2. Here, the thresholds Vth1 and Vth2 are set in the relationship Vth1 => Vth2.

[0078] The modulated signal Ms output by the comparator 514 is input to the gate driver 521 included in the gate drive circuit 520, and also to the gate driver 522 included in the gate drive circuit 520 via the inverter 515. That is, signals with mutually exclusive logic levels are input to the gate driver 521 and the gate driver 522. Here, mutually exclusive logic levels include the fact that the logic levels of the signals input to the gate driver 521 and the gate driver 522 cannot be at the same time at the H level. Therefore, the modulation circuit 510 may include, in place of or in addition to the inverter 515, a timing control circuit for controlling the timing between the modulated signal Ms input to the gate driver 521 and the signal obtained by inverting the logic level of the modulated signal Ms input to the gate driver 522.

[0079] The gate drive circuit 520 includes gate drivers 521 and 522. Gate driver 521 generates an amplification control signal Hgd by level-shifting the modulated signal Ms output from comparator 514 and outputs it from terminal HDr.

[0080] Specifically, the gate driver 521's power supply voltage is supplied via terminal Bst for the higher voltage and via terminal Sw for the lower voltage. Terminal Bst is connected to one end of capacitor C5 and the cathode of diode D1, which prevents reverse current. Terminal Sw is connected to the other end of capacitor C5. The anode of diode D1 is connected to terminal Gvd. Terminal Gvd is supplied with a voltage signal Vm, which is a DC voltage of, for example, 7.5V output by a power supply circuit (not shown). In other words, the anode of diode D1 is supplied with a voltage signal Vm. Therefore, the potential difference between terminal Bst and terminal Sw is approximately equal to the voltage value of the voltage signal Vm. As a result, the gate driver 521 generates an amplified control signal Hgd with a voltage value that is greater than the voltage value of the voltage signal Vm relative to terminal Sw, according to the input modulation signal Ms, and outputs it from terminal Hdr.

[0081] The gate driver 522 operates at a lower potential than the gate driver 521. The gate driver 522 generates an amplified control signal Lgd by level-shifting the signal obtained by inverting the logic level of the modulated signal Ms output from the comparator 514 by the inverter 515, and outputs it from terminal Ldr.

[0082] Specifically, the gate driver 522 is supplied with a voltage signal Vm on the high-voltage side and ground potential GND via terminal Gnd on the low-voltage side. The gate driver 522 then outputs an amplification control signal Lgd from terminal Ldr with a voltage value greater than the voltage value of the voltage signal Vm relative to terminal Gnd, according to the signal obtained by inverting the logic level of the input modulation signal Ms. Here, ground potential GND is the reference potential of the drive signal output circuit 52, and is, for example, 0V.

[0083] The amplification circuit 550 includes transistors M1 and M2.

[0084] Transistor M1 is a surface-mount type FET (Field Effect Transistor), and a voltage signal VHV is supplied to the drain of transistor M1 as the amplification power supply voltage for the amplification circuit 550. The gate of transistor M1 is electrically connected to one end of resistor R1, and the other end of resistor R1 is electrically connected to terminal Hdr of integrated circuit 500. In other words, the amplification control signal Hgd is input to the gate of transistor M1. The source of transistor M1 is electrically connected to terminal Sw of integrated circuit 500.

[0085] Transistor M2 is a surface-mount FET, and its drain is electrically connected to terminal Sw of integrated circuit 500. That is, the drain of transistor M2 and the source of transistor M1 are electrically connected to each other. The gate of transistor M2 is electrically connected to one end of resistor R2, and the other end of resistor R2 is electrically connected to terminal Ldr of integrated circuit 500. That is, the amplification control signal Lgd is input to the gate of transistor M2. Also, the source of transistor M2 is supplied with ground potential GND.

[0086] When the drain and source of transistor M1 are controlled to be non-conductive and the drain and source of transistor M2 are controlled to be conductive, the potential of the node to which terminal Sw is connected becomes ground potential GND. Therefore, the voltage signal Vm is supplied to terminal Bst. On the other hand, when the drain and source of transistor M1 are controlled to be conductive and the drain and source of transistor M2 are controlled to be non-conductive, the potential of the node to which terminal Sw is connected becomes the voltage value of the voltage signal VHV. Therefore, the voltage supplied to terminal Bst is the sum of the voltage value of the voltage signal VHV and the voltage value of the voltage signal Vm. In other words, the gate driver 521 that drives transistor M1 uses capacitor C5 as a floating power supply, and in accordance with the operation of transistors M1 and M2, the potential of terminal Sw changes to either the ground potential GND or the voltage value of the voltage signal VHV. This generates an amplified control signal Hgd where the L level is the voltage value of the voltage signal VHV and the H level is the voltage value of the sum of the voltage values ​​of the voltage signal VHV and the voltage value of the voltage signal Vm, and outputs this to the gate of transistor M1.

[0087] On the other hand, the gate driver 522 that drives transistor M2 generates an amplification control signal Lgd, where the L level is ground potential GND and the H level is the voltage value of the voltage signal Vm, regardless of the operation of transistors M1 and M2, and outputs it to the gate of transistor M2.

[0088] The amplifier circuit 550 configured as described above amplifies the modulated signal Ms based on the voltage signal VHV at the connection point between the source of transistor M1 and the drain of transistor M2. The amplifier circuit 550 generates a wide-modulated signal AMs. The amplifier circuit 550 then outputs the generated amplified-modulated signal AMs to the demodulation circuit 560.

[0089] Here, a capacitor C7 is provided in the propagation path through which the voltage signal VHV input to the amplification circuit 550 propagates. Specifically, one end of capacitor C7 is electrically connected to the drain of transistor M1, which is in the propagation path through which the voltage signal VHV propagates, and the other end of capacitor C7 is supplied with ground potential GND. This reduces the risk of fluctuations in the voltage value of the voltage signal VHV input to the amplification circuit 550, and also reduces the risk of noise being superimposed on the voltage signal VHV, thereby improving the waveform accuracy of the amplified modulated signal AMs output by the amplification circuit 550. For this reason, a high-voltage, large-capacity electrolytic capacitor is used. Note that capacitor C7 may be provided to correspond to one drive signal output circuit 52, or it may be provided to correspond to multiple drive signal output circuits 52.

[0090] The demodulation circuit 560 generates a drive signal COM by demodulating the amplified modulation signal AMs output by the amplification circuit 550, and outputs it from the drive signal output circuit 52. The demodulation circuit 560 includes an inductor L1 and a capacitor C1. One end of the inductor L1 is connected to one end of the capacitor C1. The amplified modulation signal AMs is input to the other end of the inductor L1. The other end of the capacitor C1 is supplied with ground potential GND. In other words, in the demodulation circuit 560, the inductor L1 and the capacitor C1 constitute a low-pass filter. The demodulation circuit 560 then demodulates the amplified modulation signal AMs by smoothing them with this low-pass filter, and outputs the demodulated signal as a drive signal COM. That is, the drive signal output circuit 52 outputs the drive signal COM from one end of the inductor L1 and one end of the capacitor C1 included in the demodulation circuit 560.

[0091] The feedback circuit 570 includes resistors R3 and R4. One end of resistor R3 is supplied with the drive signal COM, and the other end is connected to terminal Vfb and one end of resistor R4. The other end of resistor R4 is supplied with the voltage signal VHV. As a result, the drive signal COM, which has passed through the feedback circuit 570, is fed back to terminal Vfb in a state where it is pulled up with the voltage value of the voltage signal VHV.

[0092] The feedback circuit 572 includes capacitors C2, C3, and C4, and resistors R5 and R6. One end of capacitor C2 is input to the drive signal COM, and the other end is connected to one end of resistor R5 and one end of resistor R6. Ground potential GND is supplied to the other end of resistor R5. As a result, capacitor C2 and resistor R5 function as a high-pass filter. The other end of resistor R6 is connected to one end of capacitor C4 and one end of capacitor C3. Ground potential GND is supplied to the other end of capacitor C3. As a result, resistor R6 and capacitor C3 function as a low-pass filter. In other words, the feedback circuit 572 includes a high-pass filter and a low-pass filter, and functions as a band-pass filter that allows signals in a predetermined frequency range included in the drive signal COM to pass through.

[0093] The other end of capacitor C4 is connected to terminal Ifb of integrated circuit 500. As a result, terminal Ifb receives a signal from which the DC component of the high-frequency component of the drive signal COM, which has passed through the feedback circuit 572 (which functions as a bandpass filter), has been cut off.

[0094] The drive signal COM is a signal obtained by smoothing the amplified modulated signal AMs based on the base drive signal dO by the demodulation circuit 560. Furthermore, the drive signal COM is integrated and subtracted via terminal Vfb and then fed back to the adder 512. As a result, the drive signal output circuit 52 self-oscillates at a frequency determined by the feedback delay and the feedback transfer function. However, the feedback via terminal Vfb is... The feedback path has a large delay, and therefore, the self-oscillation frequency may not be high enough to ensure sufficient accuracy of the drive signal COM with feedback via terminal Vfb alone. Therefore, by providing a separate feedback path for the high-frequency component of the drive signal COM via terminal Ifb, in addition to the path via terminal Vfb, the overall delay of the circuit is reduced. As a result, the frequency of the voltage signal Os can be increased to a level that ensures sufficient accuracy of the drive signal COM compared to the case where the path via terminal Ifb does not exist.

[0095] Furthermore, the integrated circuit 500 includes a reference voltage signal output circuit 530. The reference voltage signal output circuit 530 outputs a reference voltage signal VBS. This reference voltage signal output circuit 530 is generated by using the bandgap reference voltage generated in the integrated circuit 500 as a reference potential, for example, by stepping down or stepping up a voltage signal Vm based on the said reference potential. The reference voltage signal output circuit 530 then outputs the generated reference voltage signal VBS from the drive signal output circuit 52 via terminal Vbs.

[0096] As described above, the drive signal output circuit 52 converts the input base drive signal dO from digital to analog, generates a drive signal COM by class D amplification of the analog signal, outputs the generated drive signal COM, and also generates and outputs a reference voltage signal VBS. The reference voltage signal output circuit 530 that generates the reference voltage signal VBS may have a different configuration from the drive signal output circuit 52, but it may have the same configuration as the drive signal output circuit 52 and be built into a single integrated circuit 500, thereby reducing the circuit size of the drive signal output circuit 52 and the drive circuit module 50 including the drive signal output circuit 52.

[0097] In other words, the drive signal output circuit 52 of the liquid ejection device 1 of this embodiment includes, for each of the drive signal output circuits 52a-1 to 52a-4 and 52b-1 to 52b-4, an integrated circuit 500, transistors M1 and M2, and an inductor L1. The drive signal output circuits 52a-m and 52b-m output drive signals COMAm and COMBm to the print head 30, which displace the piezoelectric element 60 in order to eject ink from the ejection module 32-m of the print head 30.

[0098] Furthermore, the reference voltage signal VBS supplied to the other end of the piezoelectric element 60 of each of the ejection modules 32-1 to 32-m is output from the integrated circuit 500 of the drive signal output circuit 52a-1. That is, the drive signal output circuit 52a-1 has a reference voltage signal output circuit 530 that outputs the reference voltage signal VBS to the print head 30, and at least a part of the reference voltage signal output circuit 530 is included in the integrated circuit 500 of the drive signal output circuit 52a-1.

[0099] 1.4 Functional Configuration of the Drive Signal Selection Circuit Next, the configuration and operation of the drive signal selection circuit 200 will be described. In describing the configuration and operation of the drive signal selection circuit 200, an example of the signal waveforms of the drive signals COMA and COMB input to the drive signal selection circuit 200, and an example of the signal waveform of the drive signal VOUT output from the drive signal selection circuit 200 will be described.

[0100] Figure 4 shows an example of the signal waveforms of the drive signals COMA and COMB. As shown in Figure 4, the drive signal COMA is a signal waveform formed by continuously combining a trapezoidal waveform Adp1, which is positioned during the period t1 from when the latch signal LAT rises until when the change signal CH rises, and a trapezoidal waveform Adp2, which is positioned during the period t2 from when the change signal CH rises until when the latch signal LAT rises. Furthermore, the trapezoidal waveform Adp1 is a signal waveform that, when supplied to the piezoelectric element 60 contained in the ejection unit 600, causes a predetermined amount of ink to be ejected from the ejection unit 600, and the trapezoidal waveform Adp2 is a signal waveform that, when supplied to the piezoelectric element 60 contained in the ejection unit 600, causes a larger amount of ink than the predetermined amount to be ejected from the ejection unit 600. Hereinafter, In the description, the amount of ink ejected from the ejection unit 600 when trapezoidal waveform Adp1 is supplied to the piezoelectric element 60 included in the ejection unit 600 may be referred to as a small amount, and the amount of ink ejected from the ejection unit 600 when trapezoidal waveform Adp2 is supplied to the piezoelectric element 60 included in the ejection unit 600 may be referred to as a medium amount.

[0101] Furthermore, as shown in Figure 4, the drive signal COMB is a signal waveform formed by continuously combining a trapezoidal waveform Bdp1 positioned during period t1 and a trapezoidal waveform Bdp2 positioned during period t2. The trapezoidal waveform Bdp1, when supplied to the piezoelectric element 60 included in the ejection unit 600, is a signal waveform that prevents ink from being ejected from the ejection unit 600, while the trapezoidal waveform Bdp2, when supplied to the piezoelectric element 60 included in the ejection unit 600, is a signal waveform that causes a small amount of ink to be ejected from the ejection unit 600. Here, the trapezoidal waveform Bdp1 is a signal waveform that prevents an increase in ink viscosity by vibrating the ink near the nozzle opening in the ejection unit 600 to the extent that ink is not ejected. In the following description, the operation of vibrating the ink near the nozzle opening when the trapezoidal waveform Bdp1 is supplied to the piezoelectric element 60 of the ejection unit 600 may be referred to as micro-vibration.

[0102] As shown in Figure 4, the voltage values ​​at the start and end timings of the trapezoidal waveforms Adp1, Adp2, Bdp1, and Bdp2 are all the same, at voltage Vc. That is, each of the trapezoidal waveforms Adp1, Adp2, Bdp1, and Bdp2 starts and ends at voltage Vc. The period tp, consisting of periods t1 and t2, corresponds to the printing cycle that forms new dots on the medium P.

[0103] In Figure 4, the case where the trapezoidal waveform Adp1 and the trapezoidal waveform Bdp2 are the same signal waveform is shown, but the trapezoidal waveform Adp1 and the trapezoidal waveform Bdp2 may be different signal waveforms. Also, in the explanation, it is assumed that a small amount of ink is ejected from the ejection unit 600 in both cases where the trapezoidal waveform Adp1 is supplied to the piezoelectric element 60 included in the ejection unit 600 and where the trapezoidal waveform Bdp2 is supplied to the piezoelectric element 60 included in the ejection unit 600, but this is not the only case. In other words, the signal waveforms of the drive signals COMA and COMB are not limited to the signal waveforms shown in Figure 4, and various combinations of signal waveforms may be used depending on the properties of the ink ejected from the ejection unit 600 and the material of the medium P to which the ejected ink lands.

[0104] Furthermore, while Figure 4 illustrates a case where the timing for switching between trapezoidal waveforms Adp1 and Adp2 included in drive signal COMA, and the timing for switching between trapezoidal waveforms Bdp1 and Bdp2 included in drive signal COMB, are defined by a single change signal CH, the change signal CH that defines the timing for switching between trapezoidal waveforms Adp1 and Adp2 included in drive signal COMA and the change signal CH that defines the timing for switching between trapezoidal waveforms Bdp1 and Bdp2 included in drive signal COMB may be different signals.

[0105] Figure 5 shows an example of the signal waveform of the drive signal VOUT for each case where the size of the dots formed on the medium P is large dot LD, medium dot MD, small dot SD, and non-recorded ND.

[0106] As shown in Figure 5, when a large dot LD is formed on the medium P, the drive signal VOUT is a continuous signal waveform consisting of a trapezoidal waveform Adp1 positioned at period t1 of the period tp and a trapezoidal waveform Adp2 positioned at period t2 of the period tp. When this drive signal VOUT is supplied to the piezoelectric element 60 included in the ejection unit 600, a small amount of ink and a medium amount of ink are ejected from the corresponding ejection unit 600. Then, each ink lands on the medium P and combines, forming a large dot LD on the medium P during period tp.

[0107] When a medium dot MD is formed on the medium P, the drive signal VOUT is a continuous signal waveform consisting of a trapezoidal waveform Adp1 positioned during period t1 of the period tp and a trapezoidal waveform Bdp2 positioned during period t2 of the period tp. When this drive signal VOUT is supplied to the piezoelectric element 60 included in the ejection unit 600, a small amount of ink is ejected twice from the corresponding ejection unit 600. Then, each ink droplet lands on the medium P and combines, forming a medium dot MD on the medium P during period tp.

[0108] When small dots SD are formed on the medium P, the drive signal VOUT is a continuous signal waveform consisting of a trapezoidal waveform Adp1 positioned during period t1 of the period tp, and a constant voltage Vc signal waveform positioned during period t2 of the period tp. When this drive signal VOUT is supplied to the piezoelectric element 60 included in the ejection unit 600, a small amount of ink is ejected once from the corresponding ejection unit 600. When this ink lands on the medium P, small dots SD are formed on the medium P during period tp.

[0109] The drive signal VOUT corresponding to non-recording ND, which does not form dots on the medium P, is a continuous signal waveform consisting of a trapezoidal waveform Bdp1 positioned during period t1 of the period tp, and a constant voltage Vc signal waveform positioned during period t2 of the period tp. When this drive signal VOUT is supplied to the piezoelectric element 60 included in the ejection unit 600, only the ink near the nozzle opening of the corresponding ejection unit 600 vibrates slightly, and no ink is ejected from the ejection unit 600. Therefore, no dots are formed on the medium P during period tp.

[0110] Here, a constant signal waveform with a voltage Vc in the drive signal VOUT refers to the case where none of the trapezoidal waveforms Adp1, Adp2, Bdp1, and Bdp2 are selected as the drive signal VOUT, and the voltage Vc immediately preceding the trapezoidal waveform Adp1, Adp2, Bdp1, and Bdp2 corresponds to the voltage value held by the capacitive component of the piezoelectric element 60 included in the discharge unit 600. In other words, when none of the trapezoidal waveforms Adp1, Adp2, Bdp1, and Bdp2 are selected as the drive signal VOUT, the voltage Vc that was supplied immediately before is supplied to the piezoelectric element 60 included in the discharge unit 600 as the drive signal VOUT.

[0111] Here, the drive signal selection circuit 200 selects or deselects the trapezoidal waveforms Adp1 and Adp2 included in the drive signal COMA and the trapezoidal waveforms Bdp1 and Bdp2 included in the drive signal COMB, thereby generating a drive signal VOUT that corresponds individually to each of the multiple discharge units 600, as shown in Figure 5, and outputting it to the piezoelectric element 60 included in the corresponding discharge unit 600.

[0112] Figure 6 shows the functional configuration of the drive signal selection circuit 200. As shown in Figure 6, the drive signal selection circuit 200 includes a selection control circuit 210 and a plurality of selection circuits 230. Figure 6 also shows a plurality of discharge units 600 to which the drive signal VOUT output from the drive signal selection circuit 200 is supplied. In the following description, the discharge module 32, which includes the drive signal selection circuit 200 and the plurality of discharge units 600, will be described as having p discharge units 600.

[0113] The selection control circuit 210 receives the print data signal SI, the clock signal SCK, the latch signal LAT, and the change signal CH. The selection control circuit 210 is provided with a set of register 212, latch circuit 214, and decoder 216 corresponding to each of the p ejection units 600. That is, the selection control circuit 210 includes at least the same number of register 212, latch circuit 214, and decoder 216 sets as there are p ejection units 600.

[0114] The print data signal SI is a signal synchronized with the clock signal SCK, and for each of the p ejection units 600, it is a large dot LD, a medium dot MD, a small dot SD, and a non-recorded ND. It is a 2p-bit signal that serially includes 2 bits of print data [SIH,SIL] for selecting between two options. The print data signal SI is held in register 212 for each piece of print data [SIH,SIL] contained in the print data signal SI, corresponding to the p ejectors 600.

[0115] Specifically, in the selection control circuit 210, the registers 212 are connected in cascading order to form a p-stage shift register. The print data [SIH, SIL] input serially as the print data signal SI is then sequentially transferred to the subsequent registers 212 according to the clock signal SCK. When the supply of the clock signal SCK stops, the print data [SIH, SIL] corresponding to each of the p ejectors 600 is held in the register 212 corresponding to each of the p ejectors 600. In the following explanation, to distinguish the p registers 212 that constitute the shift register, they may be referred to as stages 1, 2, ..., p, from the upstream side to the downstream side where the print data signal SI propagates.

[0116] Each of the p latch circuits 214 corresponds to one of the p registers 212. Each latch circuit 214 simultaneously latches the print data [SIH,SIL] held in each of the p registers 212 on the rising edge of the latch signal LAT and outputs it to the corresponding decoder 216.

[0117] Figure 7 shows an example of the decoding content in decoder 216. Decoder 216 generates and outputs selection signals S1 and S2 by decoding the print data [SIH,SIL] latched by latch circuit 214 with the content shown in Figure 7. For example, if the input print data [SIH,SIL] is [1,0], decoder 216 outputs the logic level of selection signal S1 as H and L levels for periods t1 and t2 to selection circuit 230, and the logic level of selection signal S2 as L and H levels for periods t1 and t2 to selection circuit 230.

[0118] The selection circuit 230 is provided in correspondence to each of the p discharge units 600. That is, the drive signal selection circuit 200 has at least p selection circuits 230, the same number as the p discharge units 600. Figure 8 shows the configuration of the selection circuit 230 corresponding to one discharge unit 600. As shown in Figure 8, the selection circuit 230 includes inverters 232a, 232b and transfer gates 234a, 234b, which are NOT circuits.

[0119] The selection signal S1 is input to the unmarked positive control terminal of transfer gate 234a, while being logically inverted by inverter 232a and input to the marked negative control terminal of transfer gate 234a. A drive signal COMA is also supplied to the input terminal of transfer gate 234a. The selection signal S2 is input to the unmarked positive control terminal of transfer gate 234b, while being logically inverted by inverter 232b and input to the marked negative control terminal of transfer gate 234b. A drive signal COMB is also supplied to the input terminal of transfer gate 234b. The output terminals of transfer gate 234a and transfer gate 234b are then connected in common. The signal at this common connection terminal is output as the drive signal VOUT.

[0120] Specifically, when the selection signal S1 is at a high level, the input and output terminals of the transfer gate 234a become conductive, and when the selection signal S1 is at a low level, the input and output terminals of the transfer gate 234a become non-conductive. Also, when the selection signal S2 is at a high level, the input and output terminals of the transfer gate 234b become conductive, and when the selection signal S2 is at a low level... In the case of a level, the connection between the input and output terminals of the transfer gate 234b becomes non-conductive. That is, the selection circuit 230 selects or deselects the signal waveforms of the drive signals COMA and COMB supplied to the input terminals of the transfer gates 234a and 234b by switching the conduction state between the input and output terminals of the transfer gates 234a and 234b based on the selection signals S1 and S2, and outputs the drive signal VOUT to the connection terminal where the output terminals of the transfer gate 234a and the output terminals of the transfer gate 234b are commonly connected.

[0121] The operation of the drive signal selection circuit 200 will be explained using Figure 9. Figure 9 is a diagram illustrating the operation of the drive signal selection circuit 200. The print data [SIH,SIL] included in the print data signal SI is input serially in synchronization with the clock signal SCK. The print data [SIH,SIL] is then sequentially transferred in the registers 212 that constitute the shift register, corresponding to the p ejection units 600, in synchronization with the clock signal SCK. Subsequently, when the supply of the clock signal SCK is stopped, each of the registers 212 holds the print data [SIH,SIL] corresponding to each of the p ejection units 600. The print data [SIH,SIL] included in the print data signal SI is input in the order corresponding to the p, ..., 2, and 1 stage ejection units 600 of the registers 212 that constitute the shift register.

[0122] Then, when the latch signal LAT rises, each of the latch circuits 214 simultaneously latches the print data [SIH,SIL] held in the register 212. In Figure 9, LS1, LS2, ..., LSp represent the print data [SIH,SIL] latched by the latch circuits 214 corresponding to the 1st, 2nd, ..., pth stage registers 212.

[0123] The decoder 216 outputs the logic levels of the selection signals S1 and S2 in the manner shown in Figure 7, for each of the periods t1 and t2, according to the size of the dots defined by the latched print data [SIH, SIL].

[0124] Specifically, when the input print data [SIH,SIL] is [1,1], the decoder 216 sets the logic level of selection signal S1 to H,H level during periods t1 and t2, and the logic level of selection signal S2 to L,L level during periods t1 and t2. In this case, the selection circuit 230 selects trapezoidal waveform Adp1 during period t1 and trapezoidal waveform Adp2 during period t2. As a result, a drive signal VOUT corresponding to the large dot LD shown in Figure 5 is generated at the output terminal of the selection circuit 230.

[0125] Furthermore, when the input print data [SIH,SIL] is [1,0], the decoder 216 sets the logic level of selection signal S1 to H and L levels during periods t1 and t2, and the logic level of selection signal S2 to L and H levels during periods t1 and t2. In this case, the selection circuit 230 selects trapezoidal waveform Adp1 during period t1 and trapezoidal waveform Bdp2 during period t2. As a result, a drive signal VOUT corresponding to the middle dot MD shown in Figure 5 is generated at the output terminal of the selection circuit 230.

[0126] Furthermore, when the input print data [SIH,SIL] is [0,1], the decoder 216 sets the logic level of selection signal S1 to H,L level during periods t1 and t2, and the logic level of selection signal S2 to L,L level during periods t1 and t2. In this case, the selection circuit 230 selects trapezoidal waveform Adp1 during period t1, and does not select either trapezoidal waveform Adp2 or Bdp2 during period t2. As a result, a drive signal VOUT corresponding to the small dot SD shown in Figure 5 is generated at the output terminal of the selection circuit 230.

[0127] Furthermore, the decoder 216 will check if the input print data [SIH,SIL] is [0,0] In this case, the logic level of selection signal S1 is set to L, L level during periods t1 and t2, and the logic level of selection signal S2 is set to H, L level during periods t1 and t2. In this case, the selection circuit 230 selects the trapezoidal waveform Bdp1 during period t1, and does not select either the trapezoidal waveform Adp2 or Bdp2 during period t2. As a result, a drive signal VOUT corresponding to the non-recorded ND shown in Figure 5 is generated at the output terminal of the selection circuit 230.

[0128] As described above, the drive signal selection circuit 200 generates and outputs the drive signal VOUT by selecting the signal waveforms of the drive signal COMA and drive signal COMB based on the print data signal SI, the clock signal SCK, the latch signal LAT, and the change signal CH.

[0129] 2. Head unit structure 2.1 Head Unit Structure Next, the structure of the head unit 3 of the liquid dispensing device 1 will be described. Figure 10 is a side view showing the structure of the carriage 8 on which the head unit 3 is mounted. Figure 11 is a perspective view showing the surrounding structure of the carriage 8 on which the head unit 3 is mounted. Hereinafter, the X, Y, and Z axes, which are orthogonal to each other, will be illustrated and described.In addition, in the following description, the starting point of the arrows illustrated along the X axis will be referred to as the -X side and the tip as the +X side, the starting point of the arrows illustrated along the Y axis will be referred to as the -Y side and the tip as the +Y side, and the starting point of the arrows illustrated along the Z axis will be referred to as the -Z side and the tip as the +Z side.Furthermore, in the following description, the plane consisting of the X and Y axes will be referred to as the XY plane, the plane consisting of the X and Z axes will be referred to as the XZ plane, and the plane consisting of the Y and Z axes will be referred to as the YZ plane.

[0130] As shown in Figures 10 and 11, the carriage 8 includes a carriage body 81, a carriage cover 82, and a housing case 83. The carriage body 81 includes a mounting portion 85 and a fixing portion 86. The mounting portion 85 is a plate-shaped member extending along the XY plane, and the fixing portion 86 is a plate-shaped member extending along the YZ plane from the -Y end of the mounting portion 85 toward the -Z side. That is, the carriage body 81 has an L-shaped cross-section when viewed along the X axis. The carriage cover 82 is located on the -Z side of the carriage body 81 and is detachably attached to the carriage body 81. At this time, the carriage body 81 and the carriage cover 82 form a closed space. The housing case 83 is a substantially rectangular parallelepiped shape containing a housing space capable of housing various components inside, and the +Y end of the housing case 83 is fixed to the -Z end of the fixing portion 86 on the -Y side of the carriage body 81.

[0131] Furthermore, a carriage support portion 87 is formed on the -Y side surface of the fixed portion 86 included in the carriage body 81. The guide rail 72 formed on the +Y side of the carriage guide shaft 7 is fitted into this carriage support portion 87, thereby movably supporting the carriage support portion 87 on the carriage guide shaft 7. This allows the carriage 8 to move along the carriage guide shaft 7.

[0132] In the internal space of the carriage 8 configured as described above, the closed space formed by the carriage body 81 and the carriage cover 82, and the housing space formed inside the housing case 83, house the discharge control module 10, a plurality of liquid discharge modules 20, a plurality of FFC cables 21 and FFC cables 22 corresponding to the plurality of liquid discharge modules 20. Here, the liquid discharge device 1 of this embodiment will be described assuming that it has five liquid discharge modules 20. That is, the internal space of the carriage 8 of this embodiment houses five liquid discharge modules 20, five FFC cables 21 and five FFC cables 22. Note that the number of liquid discharge modules 20 provided in the liquid discharge device 1 is not limited to five.

[0133] The discharge control module 10 is housed in a housing space formed inside the housing case 83. The ejection control module 10 includes a control circuit board 100 and an integrated circuit 110 mounted on the control circuit board 100. The integrated circuit 110 also constitutes part or all of the head control circuit 12 described above.

[0134] The five FFC cables 21 and five FFC cables 22 are provided corresponding to the five liquid dispensing modules 20. Specifically, one end of each of the five FFC cables 21 and one end of each of the five FFC cables 22 are electrically connected to the control circuit board 100. The other ends of each of the five FFC cables 21 and the other ends of each of the five FFC cables 22 are electrically connected to the corresponding liquid dispensing modules 20. In other words, each of the five liquid dispensing modules 20 is electrically connected to the other end of the FFC cable 21 and the other end of the FFC cable 22. Such FFC cables 21 and 22 are, for example, flexible flat cables (FFC). A flat cable can be used.

[0135] The five liquid ejection modules 20 each have a drive circuit module 50 and a print head 30, and are housed in a closed space formed by the carriage body 81 and the carriage cover 82. The five liquid ejection modules 20 are mounted on the mounting section 85 at equal intervals along the X axis.

[0136] The other end of FFC cable 21 and the other end of FFC cable 22 are electrically connected to the drive circuit module 50 of the corresponding liquid ejection module 20 on the -Z side. The print head 30 is located on the +Z side of the drive circuit module 50. The print head 30 is mounted on the mounting section 85 at equal intervals along the X axis. At this time, the multiple ejection sections 600 of the print head 30 are exposed from the -Z side of the mounting section 85. As a result, the ink ejected from the multiple ejection sections 600 of the print head 30 is ejected onto the medium P without being obstructed by the carriage 8.

[0137] Furthermore, in the liquid ejection module 20, the print head 30 and the drive circuit module 50 are electrically connected by a connector CN1. It is preferable that a board-to-board (BtoB) connector be used as such a connector CN1.

[0138] BtoB connectors allow for the direct mating of two connectors, enabling electrical connection between a configuration with one of the two connectors and a configuration with the other of the two connectors without the need for cables. Therefore, it is possible to electrically connect a configuration with one of the two connectors and a configuration with the other of the two connectors without adding any new configurations, and to define the relative placement relationship between these configurations.

[0139] Specifically, when a BtoB connector is used as connector CN1 to electrically connect the print head 30 and the drive circuit module 50, the relative positional relationship between the print head 30 and the drive circuit module 50 is fixed. Therefore, the carriage 8 only needs to have an area to fix at least one of the print head 30 and the drive circuit module 50. In other words, the mounting area of ​​the print head 30 and the drive circuit module 50 on the carriage 8 can be reduced. This allows for a high-density arrangement of the print head 30 and the drive circuit module 50, and also enables miniaturization of the carriage 8. Furthermore, by electrically connecting the print head 30 and the drive circuit module 50 using a BtoB connector as connector CN1, the influence of impedance that may occur in the cable is eliminated, and as a result, the signal accuracy propagated between the print head 30 and the drive circuit module 50 is improved. Therefore, from the print head 30 The accuracy of the ink ejection is improved.

[0140] As described above, the print data signal pDATA and voltage signals VHV,VMV output by the control unit 2 are transmitted through cables (not shown) to the head unit 3 and input to the ejection control module 10. Based on the input print data signal pDATA and voltage signals VHV,VMV, etc., the ejection control module 10 generates a clock signal SCK, a differential print data signal Dp, and a differential drive data signal Dd corresponding to each of the five liquid ejection modules 20, and also generates a fan drive signal Fp corresponding to the liquid ejection module 20. The ejection control module 10 then outputs the generated clock signal SCK, differential print data signal Dp, differential drive data signal Dd, and fan drive signal Fp, along with the voltage signals VHV,VMV, to FFC cables 21 and 22.

[0141] The clock signal SCK, differential print data signal Dp, differential drive data signal Dd, and fan drive signal Fp output by the ejection control module 10, along with voltage signals VHV and VMV, propagate through FFC cables 21 and 22 and are input to the drive circuit module 50 of the liquid ejection module 20. The drive circuit module 50 operates based on the input clock signal SCK, differential print data signal Dp, differential drive data signal Dd, and voltage signals VHV and VMV to generate a clock signal SCK, a differential print data signal Dpt, and multiple drive signals COM for controlling the operation of the print head 30, and supplies them to the print head 30 via connector CN1. As a result, ink is ejected from the ejection unit 600 of the print head 30.

[0142] 2.2 Structure of the liquid dispensing module 2.2.1 Schematic Structure of Liquid Discharge Module Next, a specific example of the structure of the liquid ejection module 20 of the head unit 3 will be described. Figure 12 is an exploded perspective view showing an example of the structure of the liquid ejection module 20. As shown in Figure 12, the liquid ejection module 20 has a print head 30 that ejects liquid and a drive circuit module 50 electrically connected to the print head 30. Here, the print head 30 of this embodiment will be described as having four ejection modules 32, namely ejection modules 32-1 to 32-4, but the number of ejection modules 32 that the print head 30 has is not limited to four. Furthermore, the positional relationship of ejection modules 32-1 to 32-4 is not limited to the positional relationship shown in Figure 12.

[0143] As shown in Figure 12, the drive circuit module 50 includes a relay board 150, a drive circuit board 700, an opening plate 160, heat sinks 170 and 180, and heat conductive members 175 and 185.

[0144] The relay board 150 is a plate-shaped member that extends along the XY plane. The other ends of the FFC cables 21 and 22 are electrically connected to the -Z side surface of the relay board 150. A connector CN2a is provided on the +Z side surface of the relay board 150. The relay board 150 also has a through hole 158 that penetrates the relay board 150 in a direction along the Z axis. A cooling fan 59 is attached to this through hole 158. That is, the cooling fan 59 is fixed to the relay board 150 so as to generate airflow in a direction along the Z axis.

[0145] The drive circuit board 700 is located on the +Z side of the relay board 150 and includes rigid wiring members 710, 730, 750, and 770. The rigid wiring members 710, 730, 750, and 770 included in the drive circuit board 700 are electrically connected to each other. Various circuits, including the aforementioned discharge control circuit 51, drive signal output circuit 52, capacitor 53, abnormality detection circuit 54, abnormality notification circuit 55, temperature detection circuit 56, and voltage conversion circuit 58, and connector CN1a are connected to the rigid wiring members 710, 730, 750, and 770 included in the drive circuit board 700. CN2b and are implemented.

[0146] The rigid wiring member 710 is a plate-shaped member extending along the YZ plane, with its -Z end positioned along the +X end of the relay substrate 150. The rigid wiring member 730 is a plate-shaped member extending along the YZ plane, with its -Z end positioned along the -X end of the relay substrate 150. In other words, the rigid wiring member 710 is located on the +X side of the rigid wiring member 730, and the rigid wiring member 710 and the rigid wiring member 730 are positioned facing each other along the X axis.

[0147] Furthermore, the rigid wiring member 750 is a plate-shaped member that extends along the XZ plane, with its -Z end positioned along the +Y end of the relay substrate 150, its +X end positioned along the +Y end of the rigid wiring member 710, and its -X end positioned along the +Y end of the rigid wiring member 730. In other words, the rigid wiring member 750 is positioned to intersect with both the rigid wiring member 710 and the rigid wiring member 730.

[0148] The rigid wiring member 770 is a plate-shaped member extending along the XY plane, with its +X end positioned along the +Z end of the rigid wiring member 710, its -X end positioned along the +Z end of the rigid wiring member 730, and its +Y end positioned along the +Z end of the rigid wiring member 750. In other words, the rigid wiring member 770 is positioned to intersect with the rigid wiring members 710, 730, and 750.

[0149] As described above, in the drive circuit board 700, the rigid wiring member 710 and the rigid wiring member 730 are positioned opposite each other in the direction along the X axis, and the rigid wiring members 750 and 770 are positioned to cover at least a portion of the space created between the rigid wiring member 710 and the rigid wiring member 730.

[0150] Connector CN2b is located on the -X side of the rigid wiring member 710, along the -Z end of the rigid wiring member 710. That is, connector CN2b is located near the relay board 150. Connector CN2b then mates with connector CN2a, which is located on the +Z side of the relay board 150, thereby electrically connecting the drive circuit board 700, which includes the rigid wiring member 710, to the relay board 150. In other words, connectors CN2a and CN2b constitute a BtoB connector that electrically connects the drive circuit board 700 and the relay board 150 by direct mating. In the following description, the BtoB connector composed of connectors CN2a and CN2b may be referred to as connector CN2.

[0151] Connector CN1a is provided on the +Z side of the rigid wiring member 770. The drive circuit board 700 is electrically connected to the print head 30 via connector CN1a. In other words, connector CN1a corresponds to one side of connector CN1, which is a BtoB connector that electrically connects the drive circuit board 700 and the print head 30.

[0152] The heatsink 170 is located on the -X side of the rigid wiring member 730 and is attached to the rigid wiring member 730 via a heat conductive member 175. The heatsink 170 and the heat conductive member 175 absorb the heat generated in the rigid wiring member 730 and release it into the atmosphere. In this way, the heatsink 170 cools the various circuits provided in the rigid wiring member 730. From the viewpoint of thermal conductivity, material processability, and material availability, metals such as copper, copper alloys, aluminum, and aluminum alloys are used for such a heatsink 170. In addition, the heat conductive member 175 enhances the heat absorption efficiency of the heatsink 170 by increasing the contact between the heatsink 170 and the rigid wiring member 730, and is made of metal. From the viewpoint of ensuring the insulating performance between a heat sink 170 and a rigid wiring member 730, a material having flame retardancy and electrical insulation properties, such as a gel sheet or rubber sheet containing silicone or acrylic resin and possessing thermal conductivity, is used.

[0153] The heat sink 180 is located on the +X side of the rigid wiring member 710 and is attached to the rigid wiring member 710 via a heat conductive member 185. The heat sink 180 and the heat conductive member 185 absorb the heat generated in the rigid wiring member 710 and release it into the atmosphere. In this way, the heat sink 180 cools the various circuits provided in the rigid wiring member 710. From the viewpoint of thermal conductivity, material processability, and material availability, metals such as copper, copper alloys, aluminum, and aluminum alloys are used for such a heat sink 180. Furthermore, the heat conductive member 185 is made of a material that is flame-retardant and electrically insulating, such as a gel sheet or rubber sheet containing silicone or acrylic resin and possessing thermal conductivity, in order to improve the heat absorption efficiency of the heat sink 180 by increasing the adhesion between the heat sink 180 and the rigid wiring member 710, and to ensure the insulating performance between the metal heat sink 180 and the rigid wiring member 710.

[0154] The opening plate 160 is a plate-shaped member extending along the XZ plane, with its +X end positioned along the -Y end of the rigid wiring member 710, its -X end positioned along the -Y end of the rigid wiring member 730, its +Z end positioned along the -Y end of the rigid wiring member 770, and its -Z end positioned along the -Y end of the relay substrate 150. In other words, the opening plate 160 is positioned to cover at least a portion of the space created between the rigid wiring member 710 and the rigid wiring member 730, which are positioned opposite each other along the X axis.

[0155] The print head 30 is located on the +Z side of the drive circuit module 50 and has ejection modules 32-1 to 32-4 and a connector CN1b. The ejection modules 32-1 to 32-4 are located on the +Z side of the print head 30 and are provided so that at least a portion of them is exposed from the +Z side surface of the print head 30. In this case, of the four ejection modules 32, ejection modules 32-1 and 32-2 are positioned along the Y axis such that ejection module 32-1 is on the -Y side and ejection module 32-2 is on the +Y side, and of the four ejection modules 32, ejection modules 32-3 and 32-4 are positioned along the Y axis on the +X side of the aforementioned ejection modules 32-1 and 32-2 such that ejection module 32-3 is on the -Y side and ejection module 32-4 is on the +Y side. Specifically, ejection modules 32-1 and 32-2 of the four ejection modules 32 are positioned side by side along the -X side end of the print head 30, and ejection modules 32-3 and 32-4 of the four ejection modules 32 are positioned side by side along the +X side end of the print head 30.

[0156] Connector CN1b is located on the -Z side of the print head 30 and is provided so that at least a portion of it is exposed from the -Z side surface of the print head 30. Connector CN1a of the drive circuit module 50 is mated to this connector CN1b. This electrically connects the drive circuit board 700 and the print head 30. In other words, connector CN1b corresponds to the other side of connector CN1, which is a BtoB connector that electrically connects the drive circuit board 700 and the print head 30, and connector CN1a and connector CN1b together constitute the BtoB connector CN1.

[0157] 2.2.2 Printhead Structure The liquid ejection module 20 configured as described above will now be explained in more detail. First, the specific structure of the print head 30 of the liquid ejection module 20 will be explained. Figure 13 is a perspective view showing an example of the internal structure of the print head 30. In Figure 13, the head cover 350 of the print head 30 is shown with a dashed line. The internal structure of the 350 is illustrated with solid lines. Specifically, Figure 13 shows the print head 30 with the head cover 350 removed.

[0158] As shown in Figure 13, the print head 30 has a head holder 310 and a head cover 350. A flange 315 is provided at the -Y end of the head holder 310, and a flange 316 is provided at the +Y end of the head holder 310. The head holder 310 is exposed from the +Z side of the mounting portion 85 of the carriage body 81. At this time, the print head 30 is supported by the carriage body 81 with multiple ejection portions 600 exposed from the -Z side of the mounting portion 85, as the flanges 315 and 316 are supported by the mounting portion 85. These flanges 315 and 316 may be fixed to the mounting portion 85 by screws or the like (not shown).

[0159] The head cover 350 is located on the -Z side of the head holder 310 and has a housing space inside. The head cover 350 functions as a protective member that protects the various components of the print head 30 from ink mist and impact by housing them in this housing space.

[0160] The head cover 350 houses the flow path member 340, the head substrate 360, the head relay substrates 370 and 380, and the FPCs 372, 374, 376, 382, ​​384, and 386.

[0161] The flow channel member 340 has an ink flow channel (not shown) for supplying ink from the liquid container 9 to a plurality of ejection units 600. The head board 360 is located on the -Z side of the flow channel member 340 and extends along the XY plane. A connector CN1b is provided on the -Z side surface of the head board 360. At least a portion of this connector CN1b is exposed to the outside of the print head 30 by being inserted through a through hole (not shown) formed in the head cover 350.

[0162] The head relay board 370 is located on the -X side of the flow channel member 340 and extends along the YZ plane. The head relay board 370 is electrically connected to the head board 360 via the FPC 372. One end of FPC 374 and one end of FPC 376 are also connected to the head relay board 370. The other end of FPC 374 is electrically connected to the discharge module 32-1, and the other end of FPC 376 is electrically connected to the discharge module 32-2.

[0163] The head relay board 380 is located on the +X side of the flow channel member 340 and extends along the YZ plane. The head relay board 380 is electrically connected to the head board 360 via the FPC 382. One end of FPC 384 and one end of FPC 386 are also connected to the head relay board 380. The other end of FPC 384 is electrically connected to the discharge module 32-3, and the other end of FPC 386 is electrically connected to the discharge module 32-4.

[0164] As described above, the print head 30 receives various signals output by the drive circuit module 50 via connector CN1b. The signals received via connector CN1b are branched by the head board 360 and the head relay boards 370 and 380, and then supplied to the ejection modules 32-1 to 32-4, respectively. Here, the restore circuit 31 of the print head 30 is provided, for example, on the head board 360.

[0165] Figure 14 is an exploded perspective view of the print head 30 as seen from the +Z side along the Z axis. As shown in Figure 14, the head holder 310 of the print head 30 is provided with a reinforcing plate 320, a fixing plate 330, and ejection modules 32-1 to 32-4.

[0166] The head holder 310 is made of a conductive material such as metal, which has greater strength than the reinforcing plate 320. The +Z side surface of the head holder 310 is provided with four housing sections 318, each housing one of the discharge modules 32-1 to 32-4.

[0167] The four housing sections 318 have a concave shape that opens to the +Z side and individually house the discharge modules 32-1 to 32-4 fixed by the fixing plate 330. At this time, the openings of the housing sections 318 are sealed by the fixing plate 330. That is, the discharge modules 32-1 to 32-4 are individually housed inside the space formed by the housing sections 318 and the fixing plate 330. Note that the housing sections 318 may be individually provided corresponding to each of the discharge modules 32-1 to 32-4, or they may be shaped to house all of the discharge modules 32-1 to 32-4 together.

[0168] On the surface of the head holder 310 where the housing section 318 is provided, a reinforcing plate 320 and a fixing plate 330 are stacked in order from the -Z side to the +Z side along the Z axis.

[0169] The fixing plate 330 consists of a plate-shaped member made of a conductive material such as metal. The fixing plate 330 is also provided with openings 335 that penetrate along the Z-axis, through which nozzles 651 included in the multiple discharge sections 600 of each of the discharge modules 32-1 to 32-4 are exposed. These openings 335 are provided individually, corresponding to each of the discharge modules 32-1 to 32-4.

[0170] It is preferable that the reinforcing plate 320 be made of a material with greater strength than the fixing plate 330. The reinforcing plate 320 is provided with openings 325 that run through it along the Z-axis, corresponding to each of the discharge modules 32-1 to 32-4 which are joined to the fixing plate 330, and having an inner diameter larger than the outer circumference of each of the discharge modules 32-1 to 32-4. Each of the discharge modules 32-1 to 32-4, which are inserted through the openings 325 of the reinforcing plate 320, is joined to the fixing plate 330.

[0171] Furthermore, the ejection modules 32-1 to 32-4 of the print head 30 are arranged in a staggered pattern on the +Z side surface of the head holder 310. Each of the ejection modules 32-1 to 32-4 has two rows of nozzles 651, which are included in the ejection unit 600 that ejects ink, arranged side by side along the Y axis and along the X axis.

[0172] Here, the structure of the discharge section 600, including the nozzle 651, will be described. Figure 15 is a diagram showing an example of the configuration of the discharge section 600 of the discharge module 32. In addition to the discharge section 600, Figure 15 also shows a nozzle plate 632, a reservoir 641, and a supply port 661.

[0173] As shown in Figure 15, the discharge section 600 includes a piezoelectric element 60, a diaphragm 621, a cavity 631, and a nozzle 651. The piezoelectric element 60 includes a piezoelectric body 601 and electrodes 611 and 612. The piezoelectric element 60 is configured such that the electrodes 611 and 612 are positioned to sandwich the piezoelectric body 601. Such a piezoelectric element 60 is driven so that its central portion is displaced vertically in accordance with the potential difference between the voltage supplied to electrode 611 and the voltage supplied to electrode 612. Specifically, electrode 611 is supplied with a drive signal VOUT based on a drive signal COM, and electrode 612 is supplied with a reference voltage signal VBS. When the voltage value of the drive signal VOUT supplied to electrode 611 changes, the potential difference between the drive signal VOUT supplied to electrode 611 and the reference voltage signal VBS supplied to electrode 612 changes, and the piezoelectric element 60 is driven so that its central portion is displaced vertically.

[0174] The diaphragm 621 is located below the piezoelectric element 60 in Figure 15. In other words, pressure The electrical element 60 is formed on the upper surface of the diaphragm 621 in Figure 15. This diaphragm 621 is displaced vertically as the piezoelectric element 60 is driven vertically.

[0175] Below the diaphragm 621 in Figure 15, a cavity 631 is located. Ink is supplied to the cavity 631 from the reservoir 641. In addition, ink stored in the liquid container 9 is introduced into the reservoir 641 via the supply port 661. In other words, the inside of the cavity 631 is filled with ink stored in the liquid container 9. The internal volume of this cavity 631 expands or contracts with the vertical displacement of the diaphragm 621. That is, the diaphragm 621 functions as a diaphragm that changes the internal volume of the cavity 631, and the cavity 631 functions as a pressure chamber whose internal pressure changes with the vertical displacement of the diaphragm 621.

[0176] The nozzle 651 is an opening in the nozzle plate 632 that communicates with the cavity 631. When the internal volume of the cavity 631 changes, the ink filled inside the cavity 631 is ejected from the nozzle 651 in accordance with the change in internal volume.

[0177] In the ejection unit 600 configured as described above, when the piezoelectric element 60 is driven to bend upward, the diaphragm 621 is displaced upward. This expands the internal volume of the cavity 631, and as a result, the ink stored in the reservoir 641 is drawn into the cavity 631. On the other hand, when the piezoelectric element 60 is driven to bend downward, the diaphragm 621 is displaced downward. This reduces the internal volume of the cavity 631, and as a result, an amount of ink corresponding to the degree of reduction in the internal volume of the cavity 631 is ejected from the nozzle 651. In other words, an amount of ink corresponding to the voltage value of the drive signal VOUT is ejected from each of the multiple ejection units 600 included in the ejection module 32 of the print head 30.

[0178] Furthermore, the piezoelectric element 60 is driven by a drive signal VOUT corresponding to the drive signal COM, and the structure is not limited to the structure shown in Figure 15, as long as it is designed to be able to eject ink from the nozzle 651 when driven.

[0179] As described above, the print head 30 includes ejection modules 32-1 to 32-4 and a connector CN1b that electrically connects to the drive circuit module 50. Ejection module 32-1 includes a piezoelectric element 60 that is displaced in response to a drive signal VOUT whose voltage value changes based on drive signals COMA1 and COMB1 supplied to electrode 611, and a reference voltage signal VBS whose voltage value is constant supplied to electrode 612, and has an ejection unit 600 that ejects liquid due to the displacement of the piezoelectric element 60. Ejection module 32-2 includes a piezoelectric element 60 that is displaced in response to a drive signal VOUT whose voltage value changes based on drive signals COMA2 and COMB2 supplied to electrode 611, and a reference voltage signal VBS whose voltage value is constant supplied to electrode 612, and has an ejection unit 600 that ejects liquid due to the displacement of the piezoelectric element 60. Discharge module 32-3 includes a piezoelectric element 60 that is displaced in response to a drive signal VOUT whose voltage value changes based on drive signals COMA3, COMB3 supplied to electrode 611 and a reference voltage signal VBS whose voltage value is constant and supplied to electrode 612, and has a discharge section 600 that discharges liquid due to the displacement of the piezoelectric element 60. Discharge module 32-4 includes a piezoelectric element 60 that is displaced in response to a drive signal VOUT whose voltage value changes based on drive signals COMA4, COMB4 supplied to electrode 611 and a reference voltage signal VBS whose voltage value is constant and supplied to electrode 612, and has a discharge section 600 that discharges liquid due to the displacement of the piezoelectric element 60.

[0180] 2.2.3 Structure of the drive circuit module of the liquid discharge module Next, the structure of the drive circuit module 50 of the liquid discharge module 20 will be described. As shown in Figure 12, the drive circuit module 50 includes a relay board 150, a drive circuit board 700, an opening plate 160, heat sinks 170 and 180, and heat conductive members 175 and 185.

[0181] 2.2.3.1 Structure of the drive circuit board First, the structure of the drive circuit board 700 will be described. Figure 16 shows the planar structure of the drive circuit board 700. Here, in the following description, the x1 axis, y1 axis, and z1 axis are shown as axes that are independent of the X axis, Y axis, and Z axis mentioned above, and are mutually orthogonal. In the following description, the starting point of the arrow shown along the x1 axis will be referred to as the -x1 side and the tip as the +x1 side, the starting point of the arrow shown along the y1 axis will be referred to as the -y1 side and the tip as the +y1 side, the starting point of the arrow shown along the z1 axis will be referred to as the -z1 side and the tip as the +z1 side, and in some cases the plane consisting of the x1 axis and y1 axis will be referred to as the x1y1 plane, the plane consisting of the x1 axis and z1 axis will be referred to as the x1z1 plane, and the plane consisting of the y1 axis and z1 axis will be referred to as the y1z1 plane.

[0182] As described above, the drive circuit board 700 has rigid wiring members 710, 730, 750, and 770. The rigid wiring members 710, 730, and 750 are positioned along the y1 axis from the -y1 side to the +y1 side in the order of rigid wiring member 710, rigid wiring member 750, and rigid wiring member 730. The rigid wiring member 770 is located on the -x1 side of the rigid wiring members 710, 750, and 730, and specifically on the -x1 side of rigid wiring member 730.

[0183] The rigid wiring member 710 includes a face 723 on the +z1 side, a face 724 on the -z1 side, sides 711 and 712, and sides 713 and 714 that are longer than sides 711 and 712. Sides 711 and 712 extend along the y1 axis and face each other in the direction along the x1 axis, with side 711 on the +x1 side and side 712 on the -x1 side. Sides 713 and 714 intersect with both sides 711 and 712 and extend along the x1 axis and face each other in the direction along the y1 axis, with side 713 on the -y1 side and side 714 on the +y1 side. In other words, the rigid wiring member 710 includes sides 711 and 712 that face each other, sides 713 and 714 that intersect with sides 711 and 712 and face each other, and face 723. In other words, the rigid wiring member 710 is a substantially rectangular plate-like member that includes a face 723, a face 724 opposite to face 723, and an edge 711, and extends along the x1y1 plane.

[0184] The rigid wiring member 730 includes a face 743 on the +z1 side, a face 744 on the -z1 side, sides 731 and 732, and sides 733 and 734 that are longer than sides 731 and 732, and is located on the +y1 side of the rigid wiring member 710. Sides 731 and 732 extend along the y1 axis and face each other in the direction along the x1 axis, with side 731 on the +x1 side and side 732 on the -x1 side. Sides 733 and 734 intersect both sides 731 and 732 and extend along the x1 axis and face each other in the direction along the y1 axis, with side 733 on the -y1 side and side 734 on the +y1 side. In other words, the rigid wiring member 730 includes sides 731 and 732 that are opposite to each other, sides 733 and 734 that intersect sides 731 and 732 and are opposite to each other, and a face 743. To put it another way, the rigid wiring member 730 is a substantially rectangular plate-like member that includes a face 743, a face 744 opposite to face 743, and sides 731, and extends along the x1y1 plane.

[0185] The rigid wiring member 750 includes a face 763 on the +z1 side, a face 764 on the -z1 side, sides 751 and 752, and sides 753 and 754 which are longer than sides 751 and 752, and is located between the rigid wiring member 710 and the rigid wiring member 730 in the direction along the y1 axis. Sides 751 and 752 extend along the y1 axis and face each other in the direction along the x1 axis. In this configuration, side 751 is located on the +x1 side and side 752 is located on the -x1 side. Also, sides 753 and 754 intersect with both sides 751 and 752, and extend along the x1 axis, facing each other in the direction along the y1 axis, with side 753 on the -y1 side and side 754 on the +y1 side. In other words, the rigid wiring member 750 includes sides 751 and 752 which face each other, sides 753 and 754 which intersect with sides 751 and 752 and face each other, and face 763. In other words, the rigid wiring member 750 is a substantially rectangular plate-like member that includes face 763, face 764 opposite face 763, and side 751, and extends along the x1y1 plane.

[0186] The rigid wiring member 770 includes a face 783 on the +z1 side, a face 784 on the -z1 side, sides 771 and 772, and sides 773 and 774 that are shorter than sides 771 and 772, and is located on the -x1 side of the rigid wiring member 730 in the direction along the x1 axis. Sides 771 and 772 extend along the y1 axis and face each other in the direction along the x1 axis, with side 771 on the +x1 side and side 772 on the -x1 side. Also, sides 773 and 774 intersect both sides 771 and 772 and extend along the x1 axis and face each other in the direction along the y1 axis, with side 773 on the -y1 side and side 774 on the +y1 side. In other words, the rigid wiring member 770 includes sides 771 and 772 that are opposite to each other, sides 773 and 774 that intersect sides 771 and 772 and are opposite to each other, and a face 783. In other words, the rigid wiring member 770 is a substantially rectangular plate-like member that includes a face 783, a face 784 opposite to face 783, and sides 771, and extends along the x1y1 plane.

[0187] Each of these rigid wiring members 710, 730, 750, and 770 constitutes a so-called multilayer rigid substrate, which includes a base material in which multiple layers of a rigid composite material such as glass epoxy are stacked in the direction along the z1 axis, and multiple wiring layers located between the layers of the base material, on which wiring patterns for the propagation of various signals are formed.

[0188] Here, as shown in Figure 16, in the drive circuit board 700, sides 711, 731, and 751 are positioned approximately in a straight line along the y1 axis, and sides 712, 732, and 752 are positioned approximately in a straight line along the y1 axis. That is, the lengths of sides 713 and 714 included in the rigid wiring member 710 along the x1 axis, the lengths of sides 733 and 734 included in the rigid wiring member 730 along the x1 axis, and the lengths of sides 753 and 754 included in the rigid wiring member 750 along the x1 axis are approximately equal. Furthermore, the lengths of sides 711 and 712 along the y1 axis are approximately equal to the lengths of sides 731 and 732 along the y1 axis, and the lengths of sides 751 and 752 along the y1 axis are shorter than the lengths of sides 711 and 712 along the y1 axis, and the lengths of sides 731 and 732 included in the rigid wiring member 730 along the y1 axis. In other words, the size of the rigid wiring member 710 when the drive circuit board 700 is viewed along the z1 axis is approximately equal to the size of the rigid wiring member 730 when the drive circuit board 700 is viewed along the z1 axis, and the size of the rigid wiring member 750 when the drive circuit board 700 is viewed along the z1 axis is smaller than the size of the rigid wiring member 710 and the size of the rigid wiring member 730 when the drive circuit board 700 is viewed along the z1 axis.

[0189] Furthermore, in the drive circuit board 700, sides 733 and 773 are positioned approximately in a straight line along the x1 axis, and sides 734 and 774 are positioned approximately in a straight line along the x1 axis. That is, the lengths of sides 731 and 732 included in the rigid wiring member 730 along the y1 axis are approximately equal to the lengths of sides 771 and 772 included in the rigid wiring member 770 along the y1 axis. Also, the lengths of sides 773 and 774 along the x1 axis are shorter than the lengths of sides 733 and 734 along the x1 axis, and are approximately equal to the lengths of sides 751 and 752 along the y1 axis. That is, when the drive circuit board 700 is viewed along the z1 axis, the rigid wiring member 770 The size of the rigid wiring member 770 is smaller than the size of the rigid wiring members 710, 730, and 750. In other words, when the drive circuit board 700 is viewed along the z1 axis, the size of the rigid wiring member 770 is smaller than the size of the rigid wiring member 710 when the drive circuit board 700 is viewed along the z1 axis, and is also smaller than the size of the rigid wiring member 730 when the drive circuit board 700 is viewed along the z1 axis.

[0190] The rigid wiring members 710, 730, 750, and 770 configured as described above are electrically connected to each other by the flexible wiring member 790. In other words, the rigid wiring members 710, 730, 750, and 770 are electrically connected to each other. Next, we will describe the arrangement of the rigid wiring members 710, 730, 750, and 770 and the flexible wiring member 790 that electrically connects the rigid wiring members 710, 730, 750, and 770.

[0191] Figure 17 is a cross-sectional view of the drive circuit board 700 when cut along line Aa shown in Figure 16. Figure 18 is a cross-sectional view of the drive circuit board 700 when cut along line Bb shown in Figure 16.

[0192] In the following explanation, the flexible wiring member 790 will be described by dividing it into seven regions, 701 to 707, as shown in Figures 17 and 18. Also, as shown in Figures 17 and 18, the flexible wiring member 790 includes a +z1 side surface 791 and a -z1 side surface 792. That is, the flexible wiring member 790 will be described as including surface 791, the surface 792 opposite to surface 791, and regions 701 to 707.

[0193] As shown in Figure 17, regions 701 to 705 of the flexible wiring member 790 are located in the order of region 701, region 702, region 703, region 704, and region 705, moving from the -y1 side to the +y1 side along the y1 axis. That is, region 702 is located between region 701 and region 703, region 704 is located between region 703 and region 705, and therefore regions 702, 703, and 704 are located between region 701 and region 705.

[0194] A rigid member 721, which is part of the rigid wiring member 710, is laminated on surface 791 of region 701, and a rigid member 722, which is a different part of the rigid wiring member 710, is laminated on surface 792 of region 701. That is, the rigid wiring member 710 includes the rigid member 721 and the rigid member 722. The rigid member 721 includes a surface 723 that corresponds to the +z1 side surface of the rigid wiring member 710. The rigid member 721 is laminated on surface 791 of region 701 of the flexible wiring member 790 such that surface 723 extends along surface 791 of the flexible wiring member 790. The rigid member 722 also includes a surface 724 that corresponds to the -z1 side surface of the rigid wiring member 710. The rigid member 722 is then laminated on the surface 792 of region 701 of the flexible wiring member 790 such that its surface 724 extends along the surface 792 of the flexible wiring member 790.

[0195] A rigid member 761, which is part of the rigid wiring member 750, is laminated on surface 791 of region 703, and a rigid member 762, which is a different part of the rigid wiring member 750, is laminated on surface 792 of region 703. That is, the rigid wiring member 750 includes rigid member 761 and rigid member 762. Rigid member 761 includes surface 763, which corresponds to the +z1 side surface of the rigid wiring member 750. Rigid member 761 is laminated on surface 791 of region 703 of the flexible wiring member 790, such that surface 763 extends along surface 791 of the flexible wiring member 790. Rigid member 762 includes surface 764, which corresponds to the -z1 side surface of the rigid wiring member 750. The rigid member 762 is then laminated on the surface 792 of region 703 of the flexible wiring member 790 such that its surface 764 extends along the surface 792 of the flexible wiring member 790.

[0196] A rigid member 741, which is part of the rigid wiring member 730, is laminated on surface 791 of region 705, and a rigid member 742, which is a different part of the rigid wiring member 730, is laminated on surface 792 of region 705. That is, the rigid wiring member 730 includes the rigid member 741 and the rigid member 742. The rigid member 741 includes a surface 743 corresponding to the +z1 side surface of the rigid wiring member 730. The rigid member 741 is laminated on surface 791 of region 705 of the flexible wiring member 790 such that surface 743 extends along surface 791 of the flexible wiring member 790. The rigid member 742 includes a surface 744 corresponding to the -z1 side surface of the rigid wiring member 730. The rigid member 742 is then laminated on the surface 792 of region 705 of the flexible wiring member 790 such that its surface 744 extends along the surface 792 of the flexible wiring member 790.

[0197] Regions 702 and 704 are not provided with rigid composite materials such as glass epoxy. Specifically, region 702 is located between rigid wiring member 710 and rigid wiring member 750 and is a region for separating rigid wiring member 710 and rigid wiring member 750, and region 704 is located between rigid wiring member 750 and rigid wiring member 730 and is a region for separating rigid wiring member 750 and rigid wiring member 730.

[0198] Furthermore, as shown in Figure 18, regions 705 to 707 of the flexible wiring member 790 are arranged in the order of region 705, region 706, and region 707 along the x1 axis, moving from the +x1 side to the -x1 side. That is, region 706 is located between region 705 and region 707, and between regions 701, 702, 703, 704, 705 and region 707.

[0199] A rigid member 781, which is part of the rigid wiring member 770, is laminated on surface 791 of region 707, and a rigid member 782, which is a different part of the rigid wiring member 770, is laminated on surface 792 of region 707. That is, the rigid wiring member 770 includes the rigid member 781 and the rigid member 782. The rigid member 781 includes a surface 783 corresponding to the +z1 side surface of the rigid wiring member 770. The rigid member 781 is laminated on surface 791 of region 707 of the flexible wiring member 790 such that surface 783 extends along surface 791 of the flexible wiring member 790. The rigid member 782 includes a surface 784 corresponding to the -z1 side surface of the rigid wiring member 770. The rigid member 782 is then laminated on the surface 792 of region 707 of the flexible wiring member 790 such that its surface 784 extends along the surface 792 of the flexible wiring member 790.

[0200] Region 706, like regions 702 and 704, is not provided with a rigid composite material such as glass epoxy. In other words, region 706 is located between rigid wiring member 730 and rigid wiring member 770, and is a region for separating rigid wiring member 730 and rigid wiring member 770.

[0201] In the drive circuit board 700 configured as described above, the flexible wiring member 790 constitutes at least one of the wiring layers of each of the rigid wiring members 710, 730, 750, and 770. As a result, the flexible wiring member 790 electrically connects each of the rigid wiring members 710, 730, 750, and 770 and propagates the signals generated in each of the rigid wiring members 710, 730, 750, and 770. In other words, the flexible wiring member 790 constitutes at least one of the multiple wiring layers included in the rigid wiring member 710, at least one of the multiple wiring layers included in the rigid wiring member 730, at least one of the multiple wiring layers included in the rigid wiring member 750, and at least one of the multiple wiring layers included in the rigid wiring member 770, thereby electrically connecting each of the rigid wiring members 710, 730, 750, and 770. Such flexible wiring member 790 is made of one or more layers of plastic film, polyimide, etc. This is a so-called flexible substrate, comprising a base material, one or more wiring layers on which wiring patterns for the propagation of various signals are formed, and having flexibility.

[0202] In other words, the drive circuit board 700 is a so-called rigid-flexible board that includes a plurality of rigid boards, namely rigid wiring members 710, 730, 750, and 770, and rigid members 721, 722, 741, 742, 761, 762, 781, and 782, and a flexible wiring member 790 which is a flexible board that is more flexible than the rigid wiring members 710, 730, 750, and 770.

[0203] In this embodiment, the liquid dispensing device 1 has a roughly box-like shape and is electrically connected to the print head 30. This reduces the mounting area of ​​the drive circuit board 700 in the liquid dispensing device 1, allowing for a denser arrangement of the drive circuit boards 700, and as a result, miniaturization of the liquid dispensing device 1 is achieved.

[0204] Figure 19 shows an example of the structure of a roughly box-shaped drive circuit board 700. As shown in Figure 19, the flexible wiring member 790 bends, and each of the rigid wiring members 710, 730, 750, and 770 forms one side of the roughly box-shaped drive circuit board 700.

[0205] Specifically, the region 702 of the flexible wiring member 790 is bent at approximately a right angle such that the surface 723 of the rigid wiring member 710 and the surface 763 of the rigid wiring member 750 form the inner surface of the roughly box-shaped drive circuit board 700, and the surface 724 of the rigid wiring member 710 and the surface 764 of the rigid wiring member 750 form the outer surface of the roughly box-shaped drive circuit board 700. Furthermore, the region 704 of the flexible wiring member 790 is bent at approximately a right angle such that the surface 763 of the rigid wiring member 750 and the surface 743 of the rigid wiring member 730 form the inner surface of the roughly box-shaped drive circuit board 700, and the surface 764 of the rigid wiring member 750 and the surface 744 of the rigid wiring member 730 form the outer surface of the roughly box-shaped drive circuit board 700. Furthermore, the region 706 of the flexible wiring member 790 is bent at approximately a right angle such that the surface 743 of the rigid wiring member 730 and the surface 783 of the rigid wiring member 770 form the inner surface of the substantially box-shaped drive circuit board 700, and the surface 744 of the rigid wiring member 730 and the surface 784 of the rigid wiring member 770 form the outer surface of the substantially box-shaped drive circuit board 700.

[0206] In other words, in the liquid dispensing device 1 of this embodiment, the drive circuit board 700, which has a roughly box shape, has the surfaces 723 of rigid wiring member 710, 763 of rigid wiring member 750, 743 of rigid wiring member 730, and 783 of rigid wiring member 770 forming the inner surface of the roughly box shape, and the surfaces 724 of rigid wiring member 710, 764 of rigid wiring member 750, 744 of rigid wiring member 730, and 784 of rigid wiring member 770 forming the outer surface of the roughly box shape. At this time, rigid wiring member 710 and rigid wiring member 730 are positioned such that the surface 723 of rigid wiring member 710 and the surface 743 of rigid wiring member 730 face each other when the flexible wiring member 790 bends in regions 702 and 704, and rigid wiring member 750 is positioned such that the normal direction of the surface 763 of rigid wiring member 750 is rigid when the flexible wiring member 790 bends in regions 702 and 704. The rigid wiring member 770 is positioned so as to intersect both the normal direction of the surface 723 of the wiring member 710 and the normal direction of the surface 743 of the rigid wiring member 730. The rigid wiring member 770 is positioned so that the normal direction of the surface 783 of the rigid wiring member 770 intersects both the normal direction of the surface 723 of the rigid wiring member 710 and the normal direction of the surface 743 of the rigid wiring member 730, due to the bending of the flexible wiring member 790 in region 706.

[0207] In other words, rigid member 721 and rigid member 741 are connected when the flexible wiring member 790 bends in regions 702 and 704, and the surface 723 of rigid member 721 and rigid member 741 The rigid member 761 is positioned so that its surface 743 faces the surface 743 of member 741, and the rigid member 761 is positioned so that the normal direction of the surface 763 of rigid member 761 intersects with both the normal direction of the surface 723 of rigid member 721 and the normal direction of the surface 743 of rigid member 741, due to the bending of the flexible wiring member 790 in regions 702 and 704. The rigid member 781 is positioned so that the normal direction of the surface 783 of rigid member 781 intersects with both the normal direction of the surface 723 of rigid member 721 and the normal direction of the surface 743 of rigid member 741, due to the bending of the flexible wiring member 790 in region 706.

[0208] It should be noted that the description of the drive circuit board 700 as having a roughly box shape does not necessarily mean that all sides of the roughly box shape are made of rigid substrates of a rigid-flexible substrate. In other words, it is sufficient that the shape of the drive circuit board 700 can be considered as a box shape, and as shown in Figure 19, one or more sides may be open.

[0209] In the following explanation, when describing a drive circuit board 700 that has a roughly box shape, the x2, y2, and z2 axes, which are independent of the x1, y1, and z1 axes mentioned above and are mutually orthogonal, will be illustrated and described. Furthermore, in the following explanation, the starting point of the arrow illustrated along the x2 axis may be referred to as the -x2 side and the tip as the +x2 side, the starting point of the arrow illustrated along the y2 axis may be referred to as the -y2 side and the tip as the +y2 side, the starting point of the arrow illustrated along the z2 axis may be referred to as the -z2 side and the tip as the +z2 side, the plane consisting of the x2 and y2 axes may be referred to as the x2y2 plane, the plane consisting of the x2 and z2 axes may be referred to as the x2z2 plane, and the plane consisting of the y2 and z2 axes may be referred to as the y2z2 plane. In the case of the drive circuit board 700 which has a roughly box shape, the surface 723 of rigid member 721 and the surface 743 of rigid member 741 are positioned to face each other along the x2 axis, the normal direction of the surface 723 of rigid member 721 is from the -x2 side to the +x2 side along the x2 axis, the normal direction of the surface 743 of rigid member 741 is from the +x2 side to the -x2 side along the x2 axis, the normal direction of the surface 763 of rigid member 761 is from the +y2 side to the -y2 side along the y2 axis, and the normal direction of the surface 783 of rigid member 781 is from the -z2 side to the +z2 side along the z2 axis.

[0210] Furthermore, in the following explanation, the unfolded drive circuit board 700 shown in Figures 16, 17, and 18 will be referred to as the unfolded drive circuit board 700, and the drive circuit board 700 assembled on a box-like structure as shown in Figure 19 will be referred to as the assembled drive circuit board 700.

[0211] 2.2.3.2 Component placement on the drive circuit board Next, the arrangement of electronic components constituting various circuits on the drive circuit board 700 will be described. Figure 20 shows an example of the component arrangement on the drive circuit board 700 in its unfolded state.

[0212] As shown in Figure 20, the rigid wiring member 710 is provided with multiple circuit components, including drive signal output circuits 52a-1, 52b-1, 52a-2, 52b-2, an ejection control circuit 51 configured by an FPGA, a capacitor C7a, and connectors CN2b, CN3a.

[0213] The drive signal output circuit 52a-1 includes an integrated circuit 500, transistors M1 and M2, and an inductor L1, and is provided on the surface 723 of the rigid wiring member 710 of the drive circuit board 700. At this time, the transistors M1 and M2 included in the drive signal output circuit 52a-1 are positioned in the order of transistor M1 and transistor M2 along the direction from edge 713 to edge 714, and the integrated circuit 500 included in the drive signal output circuit 52a-1 is located on the side of edge 711 of the adjacent transistors M1 and M2, and the drive signal output circuit 52a The inductor L1 included in -1 is located on the side 712 of the adjacent transistors M1 and M2.

[0214] The drive signal output circuit 52b-1 includes an integrated circuit 500, transistors M1 and M2, and an inductor L1, and is located on the side 714 of the drive signal output circuit 52a-1 on the surface 723 of the rigid wiring member 710 of the drive circuit board 700. At this time, the transistors M1 and M2 included in the drive signal output circuit 52b-1 are positioned in the order of transistor M1 and transistor M2 along the direction from side 713 to side 714, the integrated circuit 500 included in the drive signal output circuit 52b-1 is located on the side 711 of the adjacent transistors M1 and M2, and the inductor L1 included in the drive signal output circuit 52b-1 is located on the side 712 of the adjacent transistors M1 and M2.

[0215] The drive signal output circuit 52a-2 includes an integrated circuit 500, transistors M1 and M2, and an inductor L1, and is located on the side 714 of the drive signal output circuit 52b-1 on the surface 723 of the rigid wiring member 710 of the drive circuit board 700. At this time, the transistors M1 and M2 included in the drive signal output circuit 52a-2 are positioned in the order of transistor M1 and transistor M2 along the direction from side 713 to side 714, the integrated circuit 500 included in the drive signal output circuit 52a-2 is located on the side 711 of the adjacent transistors M1 and M2, and the inductor L1 included in the drive signal output circuit 52a-2 is located on the side 712 of the adjacent transistors M1 and M2.

[0216] The drive signal output circuit 52b-2 includes an integrated circuit 500, transistors M1 and M2, and an inductor L1, and is located on the side 714 of the drive signal output circuit 52a-2 on the surface 723 of the rigid wiring member 710 of the drive circuit board 700. At this time, the transistors M1 and M2 included in the drive signal output circuit 52b-2 are positioned in the order of transistor M1 and transistor M2 along the direction from side 713 to side 714, the integrated circuit 500 included in the drive signal output circuit 52b-2 is located on the side 711 of the adjacent transistors M1 and M2, and the inductor L1 included in the drive signal output circuit 52b-2 is located on the side 712 of the adjacent transistors M1 and M2.

[0217] In other words, the integrated circuit 500, transistors M1 and M2, and inductor L1 included in the drive signal output circuit 52a-1 are arranged on the surface 723 in the order of integrated circuit 500, transistors M1 and M2, and inductor L1 along the direction from side 711 to side 712, and the integrated circuit 500, transistors M1 and M2, and inductor L1 included in the drive signal output circuit 52b-1 are arranged on the surface 723 in the order of integrated circuit 500, transistors M1 and M2, and inductor L1 along the direction from side 711 to side 712. The integrated circuit 500, transistors M1, M2, and inductor L1 included in the drive signal output circuit 52a-2 are provided on the surface 723 in the order of integrated circuit 500, transistors M1, M2, and inductor L1 along the direction from side 711 to side 712, and the integrated circuit 500, transistors M1, M2, and inductor L1 included in the drive signal output circuit 52b-2 are provided on the surface 723 in the order of integrated circuit 500, transistors M1, M2, and inductor L1 along the direction from side 711 to side 712.

[0218] The drive signal output circuits 52a-1, 52a-2, 52b-1, and 52b-2 are located adjacent to each other on the surface 723 of the rigid wiring member 710 of the drive circuit board 700, moving from edge 713 to edge 714, in the order of drive signal output circuit 52a-1, drive signal output circuit 52b-1, drive signal output circuit 52a-2, and drive signal output circuit 52b-2.

[0219] In this case, drive signal output circuits 52a-1, 52a-2, 52b-1, 52b- All electronic components constituting 2 are located on the surface 723 of the rigid wiring member 710. That is, the electronic components constituting the drive signal output circuits 52a-1, 52a-2, 52b-1, and 52b-2 are not located on the surface 724 of the rigid wiring member 710.

[0220] Furthermore, the drive signal output circuits 52a-1, 52b-1, 52a-2, and 52b-2 are arranged in a staggered pattern from edge 713 to edge 714. Specifically, in the direction from edge 711 to edge 712, drive signal output circuit 52a-1 and drive signal output circuit 52a-2 are located in approximately the same position, drive signal output circuit 52b-1 and drive signal output circuit 52b-2 are located in approximately the same position, drive signal output circuit 52a-1 is located in a different position from drive signal output circuits 52b-1 and 52b-2, and drive signal output circuit 52a-2 is located in a different position from drive signal output circuits 52b-1 and 52b-2.

[0221] In detail, the drive signal output circuit 52a-1 is arranged to overlap with at least a portion of the drive signal output circuit 52b-1, at least a portion of the drive signal output circuit 52a-2, and at least a portion of the drive signal output circuit 52b-2 when viewed along the direction from edge 713 to edge 714, and the integrated circuit 500 included in the drive signal output circuit 52a-1 does not overlap with the integrated circuit 500 included in the drive signal output circuit 52b-1 and the integrated circuit 500 included in the drive signal output circuit 52b-2 when viewed along the direction from edge 713 to edge 714, but is arranged to overlap with at least a portion of the integrated circuit 500 included in the drive signal output circuit 52a-2.

[0222] In this case, the transistors M1 and M2 included in the drive signal output circuit 52a-1 may be arranged so that, when viewed along the direction from side 713 to side 714, they do not overlap with the transistors M1 and M2 included in the drive signal output circuit 52b-1 and the transistors M1 and M2 included in the drive signal output circuit 52b-2, but overlap with at least a portion of the transistors M1 and M2 included in the drive signal output circuit 52a-2. Furthermore, the inductor L1 included in the drive signal output circuit 52a-1 may be arranged so that, when viewed along the direction from side 713 to side 714, it does not overlap with the inductor L1 included in the drive signal output circuit 52b-1 and the inductor L1 included in the drive signal output circuit 52b-2, but overlaps with at least a portion of the inductor L1 included in the drive signal output circuit 52a-2.

[0223] Similarly, the drive signal output circuit 52b-1 is positioned such that, when viewed along the direction from edge 713 to edge 714, it overlaps with at least a portion of the drive signal output circuit 52a-1, at least a portion of the drive signal output circuit 52a-2, and at least a portion of the drive signal output circuit 52b-2. The integrated circuit 500 included in the drive signal output circuit 52b-1 does not overlap with the integrated circuit 500 included in the drive signal output circuit 52a-1 and the integrated circuit 500 included in the drive signal output circuit 52a-2, but is positioned such that it overlaps with at least a portion of the integrated circuit 500 included in the drive signal output circuit 52b-2.

[0224] In this case, the transistors M1 and M2 included in the drive signal output circuit 52b-1 may be arranged so that, when viewed along the direction from side 713 to side 714, they do not overlap with the transistors M1 and M2 included in the drive signal output circuit 52a-1 and the transistors M1 and M2 included in the drive signal output circuit 52a-2, but overlap with at least a portion of the transistors M1 and M2 included in the drive signal output circuit 52b-2. Furthermore, the inductor L1 included in the drive signal output circuit 52b-1 may be arranged so that, when viewed along the direction from side 713 to side 714, it does not overlap with the inductor L1 included in the drive signal output circuit 52a-1 and the inductor L1 included in the drive signal output circuit 52a-2, but overlaps with at least a portion of the inductor L1 included in the drive signal output circuit 52b-2. good.

[0225] Here, when viewed along the direction from edge 713 to edge 714, the arrangement such that drive signal output circuits 52a-1, 52b-1, 52a-2, and 52b-2 overlap in at least part means that, when viewed along the direction from edge 713 to edge 714, at least one of the electronic components included in drive signal output circuit 52a-1, at least one of the electronic components included in drive signal output circuit 52b-1, at least one of the electronic components included in drive signal output circuit 52a-2, and at least one of the electronic components included in drive signal output circuit 52b-2 overlap. This means, for example, that at least one of the integrated circuit 500, transistors M1, M2, and inductor L1 included in drive signal output circuit 52a-1, at least one of the integrated circuit 500, transistors M1, M2, and inductor L1 included in drive signal output circuit 52b-1, at least one of the integrated circuit 500, transistors M1, M2, and inductor L1 included in drive signal output circuit 52a-2, and at least one of the integrated circuit 500, transistors M1, M2, and inductor L1 included in drive signal output circuit 52b-2 overlap when viewed along the direction from side 713 to side 714.

[0226] Capacitor C7a is located on the side 711 of the drive signal output circuits 52a-1, 52b-1, 52a-2, and 52b-2, which are arranged in a row from side 713 to side 714 on the surface 723 of the rigid wiring member 710. This capacitor C7a corresponds to the aforementioned capacitor C7 corresponding to the drive signal output circuits 52a-1, 52b-1, 52a-2, and 52b-2, and reduces the risk of fluctuations in the voltage value of the voltage signal VHV supplied to each of the drive signal output circuits 52a-1, 52b-1, 52a-2, and 52b-2, as well as the risk of noise superimposed on the voltage signal VHV.

[0227] The ejection control circuit 51, which is composed of FPGAs, is located on the side 711 of the drive signal output circuits 52a-1, 52b-1, 52a-2, and 52b-2, which are arranged in a row from side 713 to side 714 on the surface 723 of the rigid wiring member 710, and on the side 714 of the capacitor C7a.

[0228] The connector CN2b includes multiple terminals TM2b and is located on side 711 of the rigid wiring member 710, closer to the capacitor C7a and the discharge control circuit 51, which are provided on surface 723 of the rigid wiring member 710. In this configuration, the connector CN2b is positioned such that the multiple terminals TM2b are arranged side by side along side 711 of the rigid wiring member 710.

[0229] The connector CN3a includes multiple terminals TM3a and is located on side 712 of the rigid wiring member 710, closer to the capacitor C7a and the discharge control circuit 51, which are provided on surface 723 of the rigid wiring member 710. In this configuration, the connector CN3a is positioned such that the multiple terminals TM3a are arranged side by side along side 712 of the rigid wiring member 710.

[0230] The rigid wiring member 730 is provided with drive signal output circuits 52a-3, 52b-3, 52a-4, 52b-4, a capacitor C7b, abnormal detection circuits 54a, 54b which serve as an abnormal detection circuit 54, and abnormal notification circuits 55a, 55b which serve as an abnormal notification circuit 55.

[0231] The drive signal output circuit 52a-3 includes an integrated circuit 500, transistors M1 and M2, and an inductor L1, and is provided on the surface 743 of the rigid wiring member 730 of the drive circuit board 700. At this time, the transistors M1 and M2 included in the drive signal output circuit 52a-3 are arranged in the direction from edge 733 to edge 734. The integrated circuit 500, included in the drive signal output circuit 52a-3, is located on the side 731 of the adjacent transistors M1 and M2, while the inductor L1, also included in the drive signal output circuit 52a-3, is located on the side 732 of the adjacent transistors M1 and M2.

[0232] The drive signal output circuit 52b-3 includes an integrated circuit 500, transistors M1 and M2, and an inductor L1, and is located on the side 734 of the rigid wiring member 730 of the drive circuit board 700, on the side 743. At this time, the transistors M1 and M2 included in the drive signal output circuit 52b-3 are positioned in the order of transistor M1 and transistor M2 along the direction from side 733 to side 734, the integrated circuit 500 included in the drive signal output circuit 52b-3 is located on the side 731 of the adjacent transistors M1 and M2, and the inductor L1 included in the drive signal output circuit 52b-3 is located on the side 732 of the adjacent transistors M1 and M2.

[0233] The drive signal output circuit 52a-4 includes an integrated circuit 500, transistors M1 and M2, and an inductor L1, and is located on the side 734 of the drive signal output circuit 52b-1 on the surface 743 of the rigid wiring member 730 of the drive circuit board 700. At this time, the transistors M1 and M2 included in the drive signal output circuit 52a-4 are positioned in the order of transistor M1 and transistor M2 along the direction from side 733 to side 734, the integrated circuit 500 included in the drive signal output circuit 52a-4 is located on the side 731 of the adjacent transistors M1 and M2, and the inductor L1 included in the drive signal output circuit 52a-4 is located on the side 732 of the adjacent transistors M1 and M2.

[0234] The drive signal output circuit 52b-4 includes an integrated circuit 500, transistors M1 and M2, and an inductor L1, and is located on the side 734 of the rigid wiring member 730 of the drive circuit board 700, on the side 743. At this time, the transistors M1 and M2 included in the drive signal output circuit 52b-4 are positioned in the order of transistor M1 and transistor M2 along the direction from side 733 to side 734, the integrated circuit 500 included in the drive signal output circuit 52b-4 is located on the side 731 of the adjacent transistors M1 and M2, and the inductor L1 included in the drive signal output circuit 52b-4 is located on the side 732 of the adjacent transistors M1 and M2.

[0235] In other words, the integrated circuit 500, transistors M1 and M2, and inductor L1 included in the drive signal output circuit 52a-3 are arranged on the surface 743 in the order of integrated circuit 500, transistors M1 and M2, and inductor L1 along the direction from side 731 to side 732, and the integrated circuit 500, transistors M1 and M2, and inductor L1 included in the drive signal output circuit 52b-3 are arranged on the surface 743 in the order of integrated circuit 500, transistors M1 and M2, and inductor L1 along the direction from side 731 to side 732. The integrated circuit 500, transistors M1, M2, and inductor L1 included in the drive signal output circuit 52a-4 are provided on the surface 743 in the order of integrated circuit 500, transistors M1, M2, and inductor L1 along the direction from side 731 to side 732, and the integrated circuit 500, transistors M1, M2, and inductor L1 included in the drive signal output circuit 52b-4 are provided on the surface 743 in the order of integrated circuit 500, transistors M1, M2, and inductor L1 along the direction from side 731 to side 732.

[0236] Furthermore, the drive signal output circuits 52a-3, 52a-4, 52b-3, and 52b-4 are located adjacent to each other on the surface 743 of the rigid wiring member 730 of the drive circuit board 700, moving from edge 733 to edge 734, in the order of drive signal output circuit 52a-3, drive signal output circuit 52b-3, drive signal output circuit 52a-4, and drive signal output circuit 52b-4.

[0237] In this case, all electronic components constituting the drive signal output circuits 52a-3, 52a-4, 52b-3, and 52b-4 are located on the surface 743 of the rigid wiring member 730. In other words, the electronic components constituting the drive signal output circuits 52a-3, 52a-4, 52b-3, and 52b-4 are not located on the surface 744 of the rigid wiring member 730.

[0238] Furthermore, the drive signal output circuits 52a-3, 52b-3, 52a-4, and 52b-4 are arranged in a staggered pattern from edge 733 to edge 734. Specifically, in the direction from edge 731 to edge 732, drive signal output circuit 52a-3 and drive signal output circuit 52a-4 are located in approximately the same position, drive signal output circuit 52b-3 and drive signal output circuit 52b-4 are located in approximately the same position, drive signal output circuit 52a-3 is located in a different position from drive signal output circuits 52b-3 and 52b-4, and drive signal output circuit 52a-4 is located in a different position from drive signal output circuits 52b-3 and 52b-4.

[0239] In detail, the drive signal output circuit 52a-3 is arranged to overlap with at least a portion of the drive signal output circuit 52b-3, at least a portion of the drive signal output circuit 52a-4, and at least a portion of the drive signal output circuit 52b-4 when viewed along the direction from edge 733 to edge 734, and the integrated circuit 500 included in the drive signal output circuit 52a-3 does not overlap with the integrated circuit 500 included in the drive signal output circuit 52b-3 and the integrated circuit 500 included in the drive signal output circuit 52b-4 when viewed along the direction from edge 733 to edge 734, but is arranged to overlap with at least a portion of the integrated circuit 500 included in the drive signal output circuit 52a-4.

[0240] In this case, the transistors M1 and M2 included in the drive signal output circuit 52a-3 may be arranged so that, when viewed along the direction from side 733 to side 734, they do not overlap with the transistors M1 and M2 included in the drive signal output circuit 52b-3 and the transistors M1 and M2 included in the drive signal output circuit 52b-4, but overlap with at least a portion of the transistors M1 and M2 included in the drive signal output circuit 52a-4. Furthermore, the inductor L1 included in the drive signal output circuit 52a-3 may be arranged so that, when viewed along the direction from side 733 to side 734, it does not overlap with the inductor L1 included in the drive signal output circuit 52b-3 and the inductor L1 included in the drive signal output circuit 52b-4, but overlaps with at least a portion of the inductor L1 included in the drive signal output circuit 52a-4.

[0241] Similarly, the drive signal output circuit 52b-3 is positioned so as to overlap with at least a portion of the drive signal output circuit 52a-3, at least a portion of the drive signal output circuit 52a-4, and at least a portion of the drive signal output circuit 52b-4 when viewed along the direction from edge 733 to edge 734, and the integrated circuit 500 included in the drive signal output circuit 52b-3 is positioned so as to not overlap with the integrated circuit 500 included in the drive signal output circuit 52a-3 and the integrated circuit 500 included in the drive signal output circuit 52a-4, but overlap with at least a portion of the integrated circuit 500 included in the drive signal output circuit 52b-4 when viewed along the direction from edge 733 to edge 734.

[0242] In this case, when viewed along the direction from side 733 to side 734, transistors M1 and M2 included in the drive signal output circuit 52b-3 may be arranged so as not to overlap with transistors M1 and M2 included in the drive signal output circuit 52a-3 and transistors M1 and M2 included in the drive signal output circuit 52a-4, but to overlap with at least a portion of transistors M1 and M2 included in the drive signal output circuit 52b-4. Furthermore, when viewed along the direction from side 733 to side 734, inductor L1 included in the drive signal output circuit 52b-3 may be arranged so as not to overlap with inductor L1 included in the drive signal output circuit 52a-3 and inductor L1 included in the drive signal output circuit 52a-3 and inductor L1 included in the drive signal output circuit 52b-3. The inductor L1 included in the motion signal output circuit 52a-4 may be positioned so as not to overlap with the inductor L1 included in the drive signal output circuit 52b-2, but to overlap with at least a portion of the inductor L1 included in the drive signal output circuit 52b-2.

[0243] Here, when viewed along the direction from edge 733 to edge 734, the arrangement such that drive signal output circuits 52a-3, 52b-3, 52a-4, and 52b-4 overlap in at least part means that, when viewed along the direction from edge 733 to edge 734, at least one of the electronic components included in drive signal output circuit 52a-3, at least one of the electronic components included in drive signal output circuit 52b-3, at least one of the electronic components included in drive signal output circuit 52a-4, and at least one of the electronic components included in drive signal output circuit 52b-4 overlap. This means, for example, that at least one of the integrated circuit 500, transistors M1, M2, and inductor L1 included in drive signal output circuit 52a-3, at least one of the integrated circuit 500, transistors M1, M2, and inductor L1 included in drive signal output circuit 52b-3, at least one of the integrated circuit 500, transistors M1, M2, and inductor L1 included in drive signal output circuit 52a-4, and at least one of the integrated circuit 500, transistors M1, M2, and inductor L1 included in drive signal output circuit 52b-4 overlap when viewed along the direction from side 733 to side 734.

[0244] Capacitor C7b is located on the side 731 of the drive signal output circuits 52a-3, 52b-3, 52a-4, and 52b-4, which are arranged in a row from side 733 to side 734 on the surface 743 of the rigid wiring member 730. This capacitor C7b corresponds to the aforementioned capacitor C7 corresponding to the drive signal output circuits 52a-3, 52b-3, 52a-4, and 52b-4, and reduces the risk of fluctuations in the voltage value of the voltage signal VHV supplied to each of the drive signal output circuits 52a-3, 52b-3, 52a-4, and 52b-4, as well as the risk of noise superimposed on the voltage signal VHV.

[0245] The abnormality detection circuits 54a and 54b are located on the side 731 of the drive signal output circuits 52a-3, 52b-3, 52a-4, and 52b-4, which are arranged in a row from side 733 to side 734 on the surface 743 of the rigid wiring member 730, and on the side 734 of the capacitor C7b. The abnormality detection circuit 54a detects whether the voltage value of the voltage signal VHV is normal, and the abnormality detection circuit 54b detects whether the voltage value of the voltage signal VDD, which is generated based on the voltage signal VMV, is normal.

[0246] The abnormality notification circuits 55a and 55b are located on the side 731 of the drive signal output circuits 52a-3, 52b-3, 52a-4, and 52b-4, which are arranged in a row from side 733 to side 734 on the surface 744 of the rigid wiring member 730, and are located in the vicinity of the abnormality detection circuits 54a and 54b. The abnormality notification circuit 55a lights up, turns off, or blinks based on the result of abnormality detection in the abnormality detection circuit 54a. The abnormality notification circuit 55b lights up, turns off, or blinks based on the result of abnormality detection in the abnormality detection circuit 54b.

[0247] The rigid wiring member 750 is provided with a temperature detection circuit 56 and a voltage conversion circuit 58.

[0248] The temperature detection circuit 56 is located at approximately the center of the rigid wiring member 750 on the surface 763 of the rigid wiring member 750. Specifically, the temperature detection circuit 56 is provided so as to overlap with the intersection of a virtual line where at least a part thereof has an equal distance from the side 751 and a virtual line where the distance from the side 752 is equal, and a virtual line where the distance from the side 753 and the distance from the side 754 are equal. The temperature detection circuit 56 detects the ambient temperature of the drive circuit module 50, and generates a temperature information signal Tt including the temperature information corresponding to the ambient temperature, and outputs it to the head control circuit 12. Such a temperature detection circuit 56 is required to comprehensively detect the temperature information of a plurality of circuits provided on the drive circuit board 700.

[0249] In the liquid ejection device 1 of the present embodiment, the temperature detection circuit 56 is provided on a rigid wiring member 750 different from the rigid wiring members 710 and 730 on which the drive signal output circuits 52 with a large heat generation amount are provided, and is further located at approximately the center of the rigid wiring member 750. As a result, the contribution degree of the drive signal output circuit 52 with a large heat generation amount is reduced, and as a result, the acquisition accuracy of the ambient temperature in the entire drive circuit module 50 is improved.

[0250] The voltage conversion circuit 58 is located on the side 751 of the temperature detection circuit 56 on the surface 763 of the rigid wiring member 750. Then, the voltage conversion circuit 58 generates and outputs a voltage signal VDD by converting the voltage value of the voltage signal VMV. The voltage signal VDD is used in various configurations provided on the drive circuit board 700, and the voltage value is smaller than the voltage signals VHV and VMV, and therefore is easily affected by noise. By providing such a voltage conversion circuit 58 that outputs the voltage signal VDD on the rigid wiring member 750 located between the rigid wiring member 710 provided with a plurality of circuits including the drive signal output circuits 52a-1, 52b-1, 52a-2, 52b-2 and the rigid wiring member 730 provided with a plurality of circuits including the drive signal output circuits 52a-3, 52b-3, 52a-4, 52b-4, the wiring length through which the voltage signal VDD propagates can be shortened. As a result, the possibility of voltage value fluctuations in the voltage signal VDD is reduced, and the possibility of noise being superimposed on the voltage signal VDD is also reduced.

[0251] The rigid wiring member 770 is provided with a capacitor 53, a connector CN3b, and a connector CN1a.

[0252] The connector CN3b includes a plurality of terminals TM3b. And the connector CN3b is positioned on the surface 783 of the rigid wiring member 770 such that the plurality of terminals TM3b are arranged side by side along the side 772.

[0253] The capacitor 53 is positioned on the surface 783 of the rigid wiring member 770. The capacitor 53 stabilizes the voltage value of the reference voltage signal VBS output by the drive signal output circuit 52a-1.

[0254] The connector CN1a is positioned on the surface 784 of the rigid wiring member 770. By fitting this connector CN1a with the connector CN1b of the print head 30, various signals generated by the drive circuit board 700 are supplied to the print head 30.

[0255] As described above, the rigid wiring member 710 surface 723 of the drive circuit board 700, specifically the surface 723 of the rigid member 721, is provided with drive signal output circuits 52a-1, 52b-1, 52a-2, 52b-2, an ejection control circuit 51 configured by an FPGA, a capacitor C7a, and connectors CN2b, CN3a. The rigid wiring member 730 surface 743, specifically the surface 743 of the rigid member 741, is provided with drive signal output circuits 52a-3, 52b-3, 52a-4, 52b-4, a capacitor C7b, and abnormality detection circuits 54a, 54b. On the surface 744 of rigid wiring member 730, which is the surface 744 of rigid member 742, abnormality notification circuits 55a and 55b are provided; on the surface 763 of rigid wiring member 750, which is the surface 763 of rigid member 761, a temperature detection circuit 56 and a voltage conversion circuit 58 are provided; on the surface 783 of rigid wiring member 770, which is the surface 783 of rigid member 781, a capacitor 53 and a connector CN3b are provided; and on the surface 784 of rigid wiring member 770, which is the surface 784 of rigid member 782, a connector CN1a is provided.

[0256] Here, we will describe an example of a wiring pattern formed on the drive circuit board 700 configured as described above, on which voltage signals VHV, VMV, and VDD, which function as power supply voltages for various circuits provided on the drive circuit board 700, propagate, and on which drive signals COMA1~COMA4, COMB1~COMB4 and a reference voltage signal VBS, generated on the drive circuit board 700, propagate.

[0257] Figure 21 shows an example of a wiring pattern through which voltage signals VHV, VMV, and VDD propagate. As mentioned above, the voltage signals VHV and VMV propagating through the drive circuit board 700 are output by the power supply voltage output circuit 18 of the control unit 2. The voltage signals VHV and VMV are then input to the drive circuit board 700 via connector CN2b.

[0258] The voltage signal VHV input via connector CN2b propagates through the wiring wh1 to wh5 provided on the flexible wiring member 790 of the drive circuit board 700, the wiring wh6 provided on the rigid wiring member 710, and the wiring wh7 provided on the rigid wiring member 730, and is input to various components provided on the drive circuit board 700 and the drive signal selection circuit 200 of the print head 30.

[0259] Wiring wh1 has one end electrically connected to terminal TM2b of connector CN2b, extends along the x1 axis toward the -x1 side, and the other end is electrically connected to wiring wh2.

[0260] The wiring wh2 is provided continuously across regions 701, 702, 703, 704, and 705. That is, the flexible wiring member 790 includes wiring wh2 through which the voltage signal VHV supplied to the drive signal selection circuit 200 and the drive signal output circuit 52 propagates, and the wiring wh2 is provided continuously across regions 701, 702, 703, 704, and 705. In this case, it is preferable that the wiring wh2 is provided linearly along the y1 axis across regions 701, 702, 703, 704, and 705. The voltage signal VHV propagated through the wiring wh2 branches in each of regions 701, 703, and 705, and is supplied to various circuits provided in the rigid wiring members 710, 730, and 750 via through-holes (not shown).

[0261] For example, wiring wh2 branches into wiring wh3 in region 701. Wiring wh3 is supplied to capacitor C7a provided in rigid wiring member 710 via a through-hole (not shown). The voltage signal VHV supplied to capacitor C7a propagates through wiring wh6 provided in rigid wiring member 710 and is supplied to drive signal output circuits 52a-1, 52a-2, 52b-1, and 52b-2, respectively.

[0262] Furthermore, for example, wiring wh2 branches into wiring wh4 in region 705. Wiring wh4 is supplied to capacitor C7b provided in rigid wiring member 730 via a through-hole (not shown). The voltage signal VHV supplied to capacitor C7b propagates through wiring wh7 provided in rigid wiring member 730 and is supplied to drive signal output circuits 52a-3, 52a-4, 52b-3, and 52b-4, respectively.

[0263] Furthermore, for example, wiring wh2 branches into wiring wh5 in region 705. Wiring wh5 propagates through regions 706 and 707 and is supplied to terminal TM1a of connector CN1a provided on rigid wiring member 770 via a through-hole (not shown). As a result, the voltage signal VHV is supplied to the drive signal selection circuit 200 of the print head 30.

[0264] As described above, the voltage signal VHV is input to the drive circuit board 700 via wiring wh1 and propagates through wiring wh2, supplying it to the various circuit configurations of the drive circuit board 700 and the print head 30. Therefore, wiring wh2 is supplied to the various circuit configurations of the drive circuit board 700. As a result, a large current is generated because the voltage signal VHV supplied to the print head 30 propagates. By continuously providing such wiring wh2 in the flexible wiring member 790 across regions 701, 702, 703, 704, and 705, there is no need to provide via wiring, and therefore the risk of impedance fluctuations in the wiring wh2 is reduced. As a result, the risk of fluctuations in the voltage value of the voltage signal VHV propagating through the wiring wh2 is reduced, and the stability of operation of various circuits that operate using the voltage signal VHV as the power supply voltage is also improved.

[0265] Furthermore, by providing wiring wh2 in a straight line across regions 701, 702, 703, 704, and 705, the risk of current density unevenness occurring at the bends in wiring wh2 is reduced. As a result, the risk of fluctuations in the voltage value of the voltage signal VHV propagating through wiring wh2 is further reduced, and the operational stability of various circuits that operate using the voltage signal VHV as the power supply voltage is further improved. Note that wiring wh2 may also have multiple branch wirings electrically connected to it in addition to wiring wh3, wh4, and wh5.

[0266] Furthermore, the voltage signal VMV input via connector CN2b propagates through the wiring wm1 to wm3 provided on the flexible wiring member 790 of the drive circuit board 700 and is input to various components provided on the drive circuit board 700.

[0267] Wiring wm1 has one end electrically connected to terminal TM2b of connector CN2b, extends along the x1 axis toward the -x1 side, and the other end is electrically connected to wiring wm2.

[0268] The wiring wm2 is provided continuously across regions 701, 702, 703, 704, and 705. Preferably, the wiring wm2 is provided linearly along the y1 axis across regions 701, 702, 703, 704, and 705. The voltage signal VMV propagated through the wiring wm2 branches out in each of regions 701, 703, and 705, and is supplied to various circuits provided in rigid wiring members 710, 730, and 750 via through-holes (not shown).

[0269] For example, wiring wm2 branches into wiring wm3 in region 703. Wiring wm3 is supplied to a voltage conversion circuit 58 via a through-hole (not shown). The voltage conversion circuit 58 then generates and outputs a voltage signal VDD based on the supplied voltage signal VMV.

[0270] As described above, the voltage signal VMV is input to the drive circuit board 700 via the wiring wm1, and is propagated through the wiring wm2 to be supplied to various circuit configurations of the drive circuit board 700. Therefore, since the voltage signal VMV supplied to various circuit configurations of the drive circuit board 700 propagates through the wiring wm2, a large amount of current is generated. By continuously providing such a wiring wm2 in the flexible wiring member 790 over the regions 701, 702, 703, 704, 705, there is no need to provide via wirings or the like. Therefore, the possibility of impedance variation in the wiring wm2 is reduced. As a result, the possibility of the voltage value of the voltage signal VMV propagating through the wiring wm2 fluctuating is reduced, and the operation stability of various circuits operating with the voltage signal VMV as the power supply voltage is also improved.

[0271] Furthermore, by providing the wiring wm2 linearly over the regions 701, 702, 703, 704, 705, the possibility of uneven current density occurring at the bent portion of the wiring wm2 is reduced. As a result, the possibility of the voltage value of the voltage signal VMV propagating through the wiring wm2 fluctuating is further reduced, and the operation stability of various circuits operating with the voltage signal VMV as the power supply voltage is further improved.

[0272] Also, the voltage signal VDD output by the voltage conversion circuit 58 propagates through the wirings wd1 and wd2 provided in the flexible wiring member 790 of the drive circuit board 700 and is input to various configurations provided on the drive circuit board 700. It is provided.

[0273] One end of the wiring wd1 is electrically connected to the voltage conversion circuit 58 and extends along the x1 axis in the +x1 direction, and the other end is electrically connected to the wiring wd2.

[0274] The wiring wd2 is provided continuously across regions 701, 702, 703, 704, and 705. Preferably, the wiring wd2 is provided linearly along the y1 axis across regions 701, 702, 703, 704, and 705. The voltage signal VDD propagated through the wiring wd2 branches out in each of regions 701, 703, and 705, and is supplied to various circuits provided in rigid wiring members 710, 730, and 750 via through-holes (not shown).

[0275] For example, wiring wd2 branches to wiring wd3 in region 701. Wiring wd3 is supplied to an FPGA including an ejection control circuit 51 via a through-hole (not shown). The ejection control circuit 51 then operates based on the supplied voltage signal VDD.

[0276] As described above, the voltage signal VDD is input to the drive circuit board 700 via wiring wd1 and propagates through wiring wd2, supplying it to various circuit configurations of the drive circuit board 700. Therefore, a large current is generated in wiring wd2 because the voltage signal VDD supplied to the various circuit configurations of the drive circuit board 700 propagates through it. By providing such wiring wd2 continuously across regions 701, 702, 703, 704, and 705 in the flexible wiring member 790, there is no need to provide via wiring, and therefore the risk of impedance fluctuations in wiring wd2 is reduced. As a result, the risk of fluctuations in the voltage value of the voltage signal VDD propagating through wiring wd2 is reduced, and the operational stability of various circuits that operate using the voltage signal VDD as the power supply voltage is also improved.

[0277] Furthermore, by providing the wiring wd2 in a straight line across regions 701, 702, 703, 704, and 705, the risk of current density unevenness occurring at the bends in the wiring wd2 is reduced. As a result, the risk of fluctuations in the voltage value of the voltage signal VDD propagating through the wiring wd2 is further reduced, and the operational stability of various circuits that use the voltage signal VDD as the power supply voltage is further improved.

[0278] Next, we will describe an example of a wiring pattern through which the drive signals COMA1~COMA4, COMB1~COMB4 and the reference voltage signal VBS, generated by the drive circuit board 700, propagate. Figure 22 shows an example of a wiring pattern through which the drive signal COM and the reference voltage signal VBS propagate.

[0279] The drive signal COMA1 output by the drive signal output circuit 52a-1 propagates through the wiring wca1 and is input to terminal TM1a of connector CN1a. Similarly, the drive signal COMB1 output by the drive signal output circuit 52b-1 propagates through the wiring wcb1 and is input to terminal TM1a of connector CN1a. Drive signals COMA1 and COMB1 are then input to the drive signal selection circuit 200 of the discharge module 32-1 via the corresponding terminal TM1a of connector CN1a.

[0280] Similarly, the drive signal COMA2 output by the drive signal output circuit 52a-2 propagates through the wiring wca2 and is input to the drive signal selection circuit 200 of the discharge module 32-2 via terminal TM1a of connector CN1a, and the drive signal COMB2 output by the drive signal output circuit 52b-2 propagates through the wiring wcb2 and is input to the drive signal selection circuit 200 of the discharge module 32-2 via terminal TM1a of connector CN1a. Similarly, the drive signal COMA3 output by the drive signal output circuit 52a-3 propagates through the wiring wca3 and is input to the connector The drive signal COMB3, output by the drive signal output circuit 52b-3, is input to the drive signal selection circuit 200 of the discharge module 32-3 via terminal TM1a of CN1a, propagates through wiring wcb3, and is input to the drive signal selection circuit 200 of the discharge module 32-3 via terminal TM1a of connector CN1a. Similarly, the drive signal COMA4 output by the drive signal output circuit 52a-4 propagates through wiring wca4 and is input to the drive signal selection circuit 200 of the discharge module 32-4 via terminal TM1a of connector CN1a, and the drive signal COMB4 output by the drive signal output circuit 52b-4 propagates through wiring wcb4 and is input to the drive signal selection circuit 200 of the discharge module 32-4 via terminal TM1a of connector CN1a.

[0281] The reference voltage signal VBS output by the reference voltage signal output circuit 530, which is included in the integrated circuit 500 of the drive signal output circuit 52a-1, propagates through wiring wb1 and is input to wiring wb2, to which capacitor 53 is electrically connected. The reference voltage signal VBS input to capacitor 53 propagates through wiring wb4 and wiring wb6 and is supplied to the electrode 612 of the piezoelectric element 60 included in discharge module 32-1 via terminal TM1a of connector CN1a. The reference voltage signal VBS input to capacitor 53 also propagates through wiring wb4 and wiring wb5 and is supplied to the electrode 612 of the piezoelectric element 60 included in discharge module 32-2 via terminal TM1a of connector CN1a. Furthermore, the reference voltage signal VBS input to capacitor 53 propagates through wiring wb3 and wiring wb7 and is supplied to the electrode 612 of the piezoelectric element 60 included in discharge module 32-3 via terminal TM1a of connector CN1a. Furthermore, the reference voltage signal VBS input to capacitor 53 propagates through wiring wb3 and wiring wb8 and is supplied to the electrode 612 of the piezoelectric element 60 included in discharge module 32-4 via terminal TM1a of connector CN1a. In other words, after being input to capacitor 53, the reference voltage signal VBS is branched and supplied to the electrode 612 of the piezoelectric element 60 in each of the discharge modules 32-1 to 32-4.

[0282] At this time, between a portion of the wiring wca1 through which the drive signal COMA1 supplied to the discharge module 32-1 propagates and a portion of the wiring wcb1 through which the drive signal COMB1 supplied to the discharge module 32-1 propagates, there is a wiring wb6 through which the reference voltage signal VBS supplied to the discharge module 32-1 propagates. Between a different portion of the wiring wca1 through which the drive signal COMA1 supplied to the discharge module 32-1 propagates and a different portion of the wiring wcb1 through which the drive signal COMB1 supplied to the discharge module 32-1 propagates, there is a wiring wg through which the ground signal propagates.

[0283] Similarly, between a portion of the wiring wca2 through which the drive signal COMA2 supplied to the discharge module 32-2 propagates and a portion of the wiring wcb2 through which the drive signal COMB2 supplied to the discharge module 32-2 propagates, there is a wiring wb5 through which the reference voltage signal VBS supplied to the discharge module 32-2 propagates. Between a different portion of the wiring wca2 through which the drive signal COMA2 supplied to the discharge module 32-2 propagates and a different portion of the wiring wcb2 through which the drive signal COMB2 supplied to the discharge module 32-2 propagates, there is a wiring wg through which the ground signal propagates.

[0284] Similarly, between a portion of the wiring wca3 through which the drive signal COMA3 supplied to the discharge module 32-3 propagates and a portion of the wiring wcb3 through which the drive signal COMB3 supplied to the discharge module 32-3 propagates, there is a wiring wb7 through which the reference voltage signal VBS supplied to the discharge module 32-3 propagates. Between a different portion of the wiring wca3 through which the drive signal COMA3 supplied to the discharge module 32-3 propagates and a different portion of the wiring wcb3 through which the drive signal COMB3 supplied to the discharge module 32-3 propagates, there is a wiring wg through which the ground signal propagates.

[0285] Similarly, between a portion of the wiring wca4 through which the drive signal COMA4 supplied to the discharge module 32-4 propagates and a portion of the wiring wcb4 through which the drive signal COMB4 supplied to the discharge module 32-4 propagates, there is a wiring wb8 through which the reference voltage signal VBS supplied to the discharge module 32-4 propagates. Between a different portion of the wiring wca4 through which the drive signal COMA4 supplied to the discharge module 32-4 propagates and a different portion of the wiring wcb4 through which the drive signal COMB4 supplied to the discharge module 32-4 propagates, there is a wiring wg through which the ground signal propagates.

[0286] In other words, the drive circuit board 700 has wiring wca1 that electrically connects the drive signal output circuit 52a-1 to the terminal TM1a of connector CN1a, wiring wcb1 that electrically connects the drive signal output circuit 52b-1 to the terminal TM1a of connector CN1a, wiring wca2 that electrically connects the drive signal output circuit 52a-2 to the terminal TM1a of connector CN1a, wiring wcb2 that electrically connects the drive signal output circuit 52b-2 to the terminal TM1a of connector CN1a, and drive signal output Wiring wca3 electrically connects power circuit 52a-3 to terminal TM1a of connector CN1a, wiring wcb3 electrically connects drive signal output circuit 52b-3 to terminal TM1a of connector CN1a, wiring wca4 electrically connects drive signal output circuit 52a-4 to terminal TM1a of connector CN1a, wiring wcb4 electrically connects drive signal output circuit 52b-4 to terminal TM1a of connector CN1a, and wiring wca4 electrically connects reference voltage signal output circuit 530 to capacitor 53. Wiring wb1 connects to the capacitor 53 and connector CN3a, and wiring wb6 branches off from wiring wb1 and propagates the reference voltage signal VBS supplied to the electrode 612 of the piezoelectric element 60 of the discharge module 32-1, and wiring wb5 connects the capacitor 53 and connector CN3a, and branches off from wiring wb1 and propagates the reference voltage signal VBS supplied to the electrode 612 of the piezoelectric element 60 of the discharge module 32-2, and capacitor - It includes wiring wb7 which electrically connects capacitor 53 to connector CN3a and branches off from wiring wb1 to propagate a reference voltage signal VBS supplied to the electrode 612 of piezoelectric element 60 of discharge module 32-3, wiring wb8 which electrically connects capacitor 53 to connector CN3a and branches off from wiring wb1 to propagate a reference voltage signal VBS supplied to the electrode 612 of piezoelectric element 60 of discharge module 32-4, and wiring wg through which a ground signal is propagated.

[0287] Furthermore, part of wiring wca1 is installed adjacent to wiring wb6, and a different part is installed adjacent to wiring wg; part of wiring wcb1 is installed adjacent to wiring wb6, and a different part is installed adjacent to wiring wg; part of wiring wca2 is installed adjacent to wiring wb5, and a different part is installed adjacent to wiring wg; part of wiring wcb2 is installed adjacent to wiring wb5, and a different part is installed adjacent to wiring wg. Wiring wca3 is provided in part adjacent to wiring wb7 and in a different part adjacent to wiring wg; Wiring wcb3 is provided in part adjacent to wiring wb7 and in a different part adjacent to wiring wg; Wiring wca4 is provided in part adjacent to wiring wb8 and in a different part adjacent to wiring wg; Wiring wcb4 is provided in part adjacent to wiring wb8 and in a different part adjacent to wiring wg.

[0288] With the above configuration, the current generated when the drive signals COMA1 and COMB1 are supplied to the discharge module 32-1 is fed back to the discharge module 32-1 via the wiring wb6 that supplies the reference voltage signal VBS. Therefore, the magnetic field generated by the current generated when the drive signals COMA1 and COMB1 are supplied to the discharge module 32-1 is canceled out by the magnetic field generated by the current fed back to the discharge module 32-1 via the wiring wb6 that supplies the reference voltage signal VBS. As a result, the waveform accuracy of the drive signals COMA1 and COMB1 supplied to the discharge module 32-1 is improved. Furthermore, the wiring wca1 and wcb1 through which the drive signals COMA1 and COMB1 are propagated to the discharge module 32-1 In a section not adjacent to the wiring wb6 that supplies the reference voltage signal VBS, a wiring wg is provided adjacent to the wiring wca1, wcb1 through which the drive signals COMA1, COMB1 are propagated to the discharge module 32-1, and through which the ground signal is propagated. This reduces the risk of noise superimposing on the drive signals COMA1, COMB1 supplied to the discharge module 32-1, and further improves the waveform accuracy of the drive signals COMA1, COMB1.

[0289] Similarly, the magnetic field generated by the current produced when the drive signals COMA2 and COMB2 are supplied to the discharge module 32-2 is canceled out by the magnetic field generated by the current fed back through the wiring wb5 that supplies the reference voltage signal VBS to the discharge module 32-2. As a result, the waveform accuracy of the drive signals COMA2 and COMB2 supplied to the discharge module 32-2 is improved. Furthermore, by providing wiring wg adjacent to wiring wca2 and wcb2 in sections where the wiring wca2 and wcb2 through which the drive signals COMA2 and COMB2 propagate is not adjacent to wiring wb5, the risk of noise superimposing on the drive signals COMA2 and COMB2 is reduced, further improving the waveform accuracy of the drive signals COMA2 and COMB2.

[0290] Similarly, the magnetic field generated by the current produced when the drive signals COMA3 and COMB3 are supplied to the discharge module 32-3 is canceled out by the magnetic field generated by the current fed back through the wiring wb7 that supplies the reference voltage signal VBS to the discharge module 32-3. As a result, the waveform accuracy of the drive signals COMA3 and COMB3 supplied to the discharge module 32-3 is improved. Furthermore, by providing wiring wg adjacent to wiring wca3 and wcb3 in sections where the wiring wca3 and wcb3, through which the drive signals COMA3 and COMB3 propagate, is not adjacent to wiring wb7, the risk of noise superimposing on the drive signals COMA3 and COMB3 is reduced, further improving the waveform accuracy of the drive signals COMA3 and COMB3.

[0291] Similarly, the magnetic field generated by the current produced when the drive signals COMA4 and COMB4 are supplied to the discharge module 32-4 is canceled out by the magnetic field generated by the current fed back through the wiring wb8 that supplies the reference voltage signal VBS to the discharge module 32-4. As a result, the waveform accuracy of the drive signals COMA4 and COMB4 supplied to the discharge module 32-4 is improved. Furthermore, by providing wiring wg adjacent to wiring wca4 and wcb4 in sections where the wiring wca4 and wcb4, through which the drive signals COMA4 and COMB4 propagate, is not adjacent to wiring wb8, the risk of noise superimposing on the drive signals COMA4 and COMB4 is reduced, further improving the waveform accuracy of the drive signals COMA4 and COMB4.

[0292] Next, the component arrangement in the assembled state of the drive circuit board 700, which is equipped with various circuits, will be described. Figure 23 shows an example of the component arrangement when the assembled drive circuit board 700 is viewed from the +x2 side along the x2 axis, and Figure 24 shows an example of the component arrangement when the assembled drive circuit board 700 is viewed from the -y2 side along the y2 axis.

[0293] As described above, in the assembled drive circuit board 700, the surface 723 of the rigid wiring member 710 on which the drive signal output circuits 52a-1, 52a-2, 52b-1, and 52b-2 are provided, and the surface 743 of the rigid wiring member 730 on which the drive signal output circuits 52a-3, 52a-4, 52b-3, and 52b-4 are provided, are located opposite each other in the direction along the x2 axis. At this time, as shown in Figure 23, when the assembled drive circuit board 700 is viewed along the x2 axis, the drive signal output circuit 52a-1 provided on the surface 723 of the rigid wiring member 710 and the drive signal output circuit 52b-4 provided on the surface 743 of the rigid wiring member 730 are arranged so that at least a portion of them overlap, and the integrated circuit 500 included in the drive signal output circuit 52a-1 and the integrated circuit 500 included in the drive signal output circuit 52b-4 are arranged so that they do not overlap.

[0294] Furthermore, in this case, the transistor M1 included in the drive signal output circuit 52a-1 M2 may be positioned so as not to overlap with transistors M1 and M2 included in the drive signal output circuit 52b-4 when viewed along the x2 axis. Furthermore, inductor L1 included in the drive signal output circuit 52a-1 may be positioned so as not to overlap with inductor L1 included in the drive signal output circuit 52b-4 when viewed along the x2 axis.

[0295] Here, when the assembled drive circuit board 700 is viewed along the x2 axis, the arrangement such that the drive signal output circuit 52a-1 and the drive signal output circuit 52b-4 overlap in at least part means that when the assembled drive circuit board 700 is viewed along the x2 axis, at least one of the electronic components included in the drive signal output circuit 52a-1 and at least one of the electronic components included in the drive signal output circuit 52b-4 overlap. For example, this includes the overlap of at least one of the integrated circuit 500, transistors M1, M2, and inductor L1 included in the drive signal output circuit 52a-1 and at least one of the integrated circuit 500, transistors M1, M2, and inductor L1 included in the drive signal output circuit 52b-4.

[0296] Similarly, when the assembled drive circuit board 700 is viewed along the x2 axis, the drive signal output circuit 52b-1 provided on the surface 723 of the rigid wiring member 710 and the drive signal output circuit 52a-4 provided on the surface 743 of the rigid wiring member 730 are arranged to overlap at least partially, while the integrated circuit 500 included in the drive signal output circuit 52b-1 and the integrated circuit 500 included in the drive signal output circuit 52a-4 are arranged not to overlap.

[0297] Furthermore, in this case, transistors M1 and M2 included in the drive signal output circuit 52b-1 may be arranged so as not to overlap with transistors M1 and M2 included in the drive signal output circuit 52a-4 when viewed along the x2 axis. In addition, inductor L1 included in the drive signal output circuit 52b-1 may be arranged so as not to overlap with inductor L1 included in the drive signal output circuit 52a-4 when viewed along the x2 axis.

[0298] Here, when the assembled drive circuit board 700 is viewed along the x2 axis, the arrangement such that the drive signal output circuit 52b-1 and the drive signal output circuit 52a-4 overlap in at least part means that when the assembled drive circuit board 700 is viewed along the x2 axis, at least one of the electronic components included in the drive signal output circuit 52b-1 and at least one of the electronic components included in the drive signal output circuit 52a-4 overlap. For example, this includes the overlap of at least one of the integrated circuit 500, transistors M1, M2, and inductor L1 included in the drive signal output circuit 52b-1 and at least one of the integrated circuit 500, transistors M1, M2, and inductor L1 included in the drive signal output circuit 52a-4.

[0299] Similarly, when the assembled drive circuit board 700 is viewed along the x2 axis, the drive signal output circuit 52a-2 provided on the surface 723 of the rigid wiring member 710 and the drive signal output circuit 52b-3 provided on the surface 743 of the rigid wiring member 730 are arranged to overlap at least partially, while the integrated circuit 500 included in the drive signal output circuit 52a-2 and the integrated circuit 500 included in the drive signal output circuit 52b-3 are arranged not to overlap.

[0300] Furthermore, in this case, transistors M1 and M2 included in the drive signal output circuit 52a-2 may be arranged so as not to overlap with transistors M1 and M2 included in the drive signal output circuit 52b-3 when viewed along the x2 axis. The inductor L1 included in the force circuit 52a-2 may be positioned so as not to overlap with the inductor L1 included in the drive signal output circuit 52b-3 when viewed along the x2 axis.

[0301] Here, when the assembled drive circuit board 700 is viewed along the x2 axis, the arrangement such that the drive signal output circuit 52a-2 and the drive signal output circuit 52b-3 overlap in at least part means that when the assembled drive circuit board 700 is viewed along the x2 axis, at least one of the electronic components included in the drive signal output circuit 52a-2 and at least one of the electronic components included in the drive signal output circuit 52b-3 overlap. For example, this includes the overlap of at least one of the integrated circuit 500, transistors M1, M2, and inductor L1 included in the drive signal output circuit 52a-2 and at least one of the integrated circuit 500, transistors M1, M2, and inductor L1 included in the drive signal output circuit 52b-3.

[0302] Similarly, when the assembled drive circuit board 700 is viewed along the x2 axis, the drive signal output circuit 52b-2 provided on the surface 723 of the rigid wiring member 710 and the drive signal output circuit 52a-3 provided on the surface 743 of the rigid wiring member 730 are arranged to overlap at least partially, while the integrated circuit 500 included in the drive signal output circuit 52b-2 and the integrated circuit 500 included in the drive signal output circuit 52a-3 are arranged not to overlap.

[0303] Furthermore, in this case, transistors M1 and M2 included in the drive signal output circuit 52b-2 may be arranged so as not to overlap with transistors M1 and M2 included in the drive signal output circuit 52a-3 when viewed along the x2 axis. In addition, inductor L1 included in the drive signal output circuit 52b-2 may be arranged so as not to overlap with inductor L1 included in the drive signal output circuit 52a-3 when viewed along the x2 axis.

[0304] Here, when the assembled drive circuit board 700 is viewed along the x2 axis, the arrangement such that the drive signal output circuit 52b-2 and the drive signal output circuit 52a-3 overlap in at least part means that when the assembled drive circuit board 700 is viewed along the x2 axis, at least one of the electronic components included in the drive signal output circuit 52b-2 and at least one of the electronic components included in the drive signal output circuit 52a-3 overlap. For example, this includes the overlap of at least one of the integrated circuit 500, transistors M1, M2, and inductor L1 included in the drive signal output circuit 52b-2 and at least one of the integrated circuit 500, transistors M1, M2, and inductor L1 included in the drive signal output circuit 52a-3.

[0305] Furthermore, as shown in Figure 23, in the assembled drive circuit board 700, the connector CN3a provided on the rigid wiring member 710 and the connector CN3b provided on the rigid wiring member 770 are mated together, thereby fixing the rigid wiring member 710 to the rigid wiring member 770. In this way, the assembled state of the drive circuit board 700, which is roughly box-shaped, is maintained by the connectors CN3a and CN3b. That is, the drive circuit board 700 has a connector CN3a provided on the rigid wiring member 710 and a connector CN3b provided on the rigid wiring member 770, and the assembled state of the drive circuit board 700 is maintained when the connectors CN3a and CN3b are mated together and the rigid wiring member 710 is fixed to the rigid wiring member 770. In other words, the connector CN3, including connectors CN3a and CN3b, functions as a retaining member that maintains the assembled state of the drive circuit board 700.

[0306] As a result, the drive circuit board 700 does not require a frame to maintain its roughly box-shaped assembled state, and therefore the mounting area of ​​the drive circuit board 700 in the liquid dispensing device 1 can be further reduced, enabling a more dense arrangement of the drive circuit boards 700 and further miniaturization of the liquid dispensing device 1.

[0307] Furthermore, connectors CN3a and CN3b, when mated together, constitute connector CN3, a BtoB connector that electrically connects rigid wiring member 710 and rigid wiring member 770. In other words, rigid wiring member 710 and rigid wiring member 770 are electrically connected via connectors CN3a and CN3b. This allows the signal generated by the circuit provided in rigid wiring member 710 to be supplied to rigid wiring member 770 via connectors CN3a and CN3b without going through rigid wiring members 730 and 750. As a result, the propagation path of the signal generated by the circuit provided in rigid wiring member 710 to rigid wiring member 770 can be shortened, reducing the risk of noise superimposing on the signal, and consequently improving the accuracy of the signal.

[0308] In this case, the signals propagated via connectors CN3a and CN3b are preferably a part of the signals generated by the rigid wiring member 710, specifically the clock signal SCK and the differential print data signal Dpt output by the ejection control circuit 51 configured with an FPGA. In other words, it is preferable that the clock signal SCK and the differential print data signal Dpt are propagated to the print head 30 via connectors CN3a and CN3b.

[0309] The clock signal SCK and differential print data signal Dpt output by the ejection control circuit 51, which is composed of an FPGA, are low-voltage signals and are susceptible to noise. Furthermore, because these signals control the operation of the print head 30, if noise is superimposed, it directly affects the ink ejection accuracy from the print head 30. By propagating these signals through connectors CN3a and CN3b, the accuracy of the clock signal SCK and differential print data signal Dpt input to the print head 30 is improved, thereby improving the ink ejection accuracy.

[0310] 2.2.3.3 Structure of the relay board Next, the structure of the relay board 150 of the drive circuit module 50 will be described. Figure 25 is a plan view showing an example of the structure of the relay board 150, and Figure 26 is a side view showing an example of the structure of the relay board 150. As shown in Figures 25 and 26, the relay board 150 includes a surface 151, a surface 152 opposite to surface 151, and edges 153, 154, 155, and 156. In the relay board 150, edges 153 and 154 are located opposite each other, edges 155 and 156 are located opposite each other, edge 153 is located so as to intersect both edges 155 and 156, and edge 154 is located so as to intersect both edges 155 and 156.

[0311] The other end of FFC cable 21 and the other end of FFC cable 22 are electrically connected to surface 151 of the relay board 150. FFC cable 21 propagates voltage signals VHV and VMV supplied to the drive circuit board 700, and FFC cable 22 propagates clock signal SCK, differential print data signal Dp, and differential drive data signal Dd supplied to the drive circuit board 700. That is, FFC cable 21 includes a plurality of signal lines, including signal lines that propagate voltage signal VHV and signal lines that propagate voltage signal VMV, and FFC cable 22 includes a plurality of signal lines, including signal lines that propagate clock signal SCK, signal lines that propagate differential print data signal Dp, and signal lines that propagate differential drive data signal Dd. Here, FFC cables 21 and 22 may also be electrically connected to the relay board 150 via FFC connectors (not shown), and the relay board may be connected by solder or the like. It may be electrically connected to 150.

[0312] A connector CN2a is provided on surface 152 of the relay board 150. Connector CN2a mates with connector CN2b provided on the drive circuit board 700. This electrically connects the relay board 150 and the drive circuit board 700. In other words, connectors CN2a and CN2b constitute connector CN2, which is a BtoB connector that directly electrically connects the relay board 150 and the drive circuit board 700 without using cables.

[0313] The relay board 150, configured as described above, receives the voltage signals VHV and VMV propagating through the FFC cable 21, and the clock signal SCK, differential print data signal Dp, and differential drive data signal Dd propagating through the FFC cable 22. The relay board 150 propagates the input voltage signals VHV, VMV, SCK, differential print data signal Dp, and differential drive data signal Dd to connector CN2a. The voltage signals VHV, VMV, SCK, differential print data signal Dp, and differential drive data signal Dd propagated to connector CN2a are then input to the drive circuit board 700 via connector CN2b.

[0314] As described above, multiple signals propagated through FFC cables 21 and 22 are input to the relay board 150. The relay board 150 propagates the input signals and outputs them to the drive circuit board 700 via connector CN2, which is a BtoB connector. In other words, the relay board 150 propagates the signals input via multiple cables. The relay board 150 outputs the signals via a number of connectors that is less than the number of cables through which the signals propagate, preferably one connector.

[0315] As a result, even if the number of cables connected to the liquid ejection module 20 increases, the drive circuit board 700 and the print head 30 electrically connected to the drive circuit board 700 can be easily attached to and detached from the liquid ejection device 1 simply by attaching and detaching the connector CN1a on the relay board 150 and the connector CN1b on the drive circuit board 700. Consequently, the workability during replacement, maintenance, and assembly of the drive circuit board 700 and the print head 30 electrically connected to the drive circuit board 700 is improved. As a result, the convenience of the liquid ejection device 1 is improved.

[0316] Furthermore, the drive circuit board 700 and print head 30 of the liquid ejection module 20 can be easily attached and detached, reducing the space required for such attachment and detachment. This allows for a more compact arrangement of the liquid ejection modules 20 in the liquid ejection device 1, resulting in further miniaturization of the liquid ejection device 1.

[0317] In the liquid dispensing device 1 configured as described above, it is preferable that the connector CN2a on the relay board 150 is a straight-type connector, and the connector CN2b on the drive circuit board 700 is a right-angle type connector, among the BtoB connectors CN2 that electrically connect the relay board 150 and the drive circuit board 700. This allows the relay board 150 to be moved along the normal direction of the surface 152 when attaching or detaching the connector CN2a on the relay board 150 to the connector CN2b on the drive circuit board 700, further reducing the space required for attachment and detachment. As a result, a more compact arrangement of the liquid dispensing modules 20 in the liquid dispensing device 1 becomes possible, enabling further miniaturization of the liquid dispensing device 1.

[0318] In such a relay board 150, the number of times connector CN2a and connector CN2b can be attached and detached is equal to the number of times the FFC cable 21 electrically connected to the relay board 150 can be attached and detached. Preferably, this number is greater than the number of times the FFC cable 22, which is electrically connected to the relay board 150, can be attached and detached.

[0319] Here, the number of times a connector can be attached and detached means the number of times a connector can be attached and detached that satisfies the desired reliability of the electrical connection, and is defined, for example, based on the wear condition of the terminal plating on the contact parts that may occur due to attachment and detachment, and the exposed state of the substrate under the terminal plating. Specifically, the number of times a connector CN2a and connector CN2b can be attached and detached may be the number of insertions and removals defined based on the specifications of connectors CN2a and CN2b. Furthermore, the number of times a FFC cable 21,22 can be attached and detached may be the number of insertions and removals of the FFC connector if the FFC cable 21,22 is electrically connected to the relay board 150 via the FFC connector, or it may be the number of times a connector can be soldered based on the soldering conditions of the FFC cable 21,22 if the FFC cable 21,22 is directly electrically connected to the relay board 150 by solder or the like.

[0320] In this embodiment, the relay board 150 outputs signals propagated via FFC cables 21 and 22 from connector CN2a, thereby enabling the liquid ejection module 20 to be attached and detached by attaching and detaching only connector CN2a. By making the number of times connector CN2a can be attached and detached greater than the number of times FFC cables 21 and 22 can be attached and detached, the risk of the reliability of the electrical connection between the relay board 150, the drive circuit board 700, and the print head 30 being compromised is reduced, even if the relay board 150 is repeatedly attached and detached. As a result, the operational stability of the liquid ejection module 20 and the reliability of the liquid ejection device 1 are improved.

[0321] Furthermore, the relay board 150 has a through hole 158 that penetrates through surfaces 151 and 152. Part of the cooling fan 59 is inserted through the through hole 158. As a result, the cooling fan 59 is fixed to the relay board 150 with at least a portion of it inserted through the through hole 158. In other words, the relay board 150 and the cooling fan 59 are integrated into a single unit. Therefore, when the relay board 150 is removed from the drive circuit board 700, the cooling fan 59 is also separated from the drive circuit board 700 together with the relay board 150, and when the relay board 150 is attached to the drive circuit board 700, the cooling fan 59 is also attached to the drive circuit board 700 together with the relay board 150.

[0322] As a result, even when a cooling fan 59 is used to cool the drive circuit board 700, the risk of the cooling fan 59 hindering the attachment and detachment of the relay board 150 from the drive circuit board 700 and the print head 30 is reduced. In this embodiment, the cooling fan 59 has been described as being fixed to the relay board 150 by being inserted through a through hole 158 formed in the relay board 150, but it may also be fixed to the relay board 150 by a retaining member (not shown) or the like that which fixes the cooling fan 59 to the relay board 150.

[0323] Furthermore, if the cooling fan 59 is fixed to the relay board 150, it is preferable that the fan drive signal Fp for driving the cooling fan 59 is supplied to the cooling fan 59 without being supplied to the drive circuit board 700. Specifically, the fan drive signal Fp for driving the cooling fan 59 is propagated along with the voltage signals VHV and VMV in the FFC cable 21 and supplied to the relay board 150. The fan drive signal Fp then propagates through the relay board 150 and is supplied to the cooling fan 59. In other words, the FFC cable 21 includes signal wiring that propagates a voltage signal VHV to drive the drive circuit board 700, signal wiring that propagates a voltage signal VMV to drive the drive circuit board 700, and signal wiring that propagates a fan drive signal Fp to drive the cooling fan 59. The signal wiring that propagates the fan drive signal Fp to drive the cooling fan 59 is electrically connected to the relay board 150, and the fan drive signal Fp propagates through the relay board 150 and is input to the cooling fan 59.

[0324] When the relay board 150 and the cooling fan 59 are configured as a single unit, the cooling fan 59 By propagating the fan drive signal Fp via the relay board 150 and supplying it to the cooling fan 59, there is no need to provide wiring for the fan drive signal Fp to propagate on the drive circuit board 700, and as a result, the risk of the drive circuit board 700 becoming larger is reduced. In other words, the risk of the drive circuit board 700 becoming larger is reduced, and the ease of attaching and detaching the liquid dispensing device 1 can be maintained.

[0325] Furthermore, although not shown in the diagram, when the cooling fan 59 is fixed to the relay board 150, the fan drive signal Fp that drives the cooling fan 59 may be supplied to the cooling fan 59 without propagating through the relay board 150. Specifically, the fan drive signal Fp that drives the cooling fan 59 is propagated together with the voltage signals VHV and VMV via the FFC cable 21. In this case, the signal wiring that propagates the fan drive signal Fp is branched from the FFC cable 21, and the branched signal wiring is directly electrically connected to the cooling fan 59. As a result, the fan drive signal Fp is supplied to the cooling fan 59 without propagating through the relay board 150. In other words, the FFC cable 21 includes signal wiring that propagates a voltage signal VHV to drive the drive circuit board 700, signal wiring that propagates a voltage signal VMV to drive the drive circuit board 700, and signal wiring that propagates a fan drive signal Fp to drive the cooling fan 59. The signal wiring that propagates the fan drive signal Fp to drive the cooling fan 59 is electrically connected to the cooling fan 59, and the fan drive signal Fp may be input to the cooling fan 59 without propagating through the relay board 150.

[0326] Even when the relay board 150 and the cooling fan 59 are integrated, and the fan drive signal Fp for driving the cooling fan 59 is not propagated by the relay board 150 but supplied directly to the cooling fan 59, there is no need to provide wiring for the fan drive signal Fp to propagate on the drive circuit board 700. As a result, the risk of the drive circuit board 700 becoming larger is reduced. In other words, even when the cooling fan 59 is used to cool the drive circuit board 700, the risk of the drive circuit board 700 becoming larger is reduced, and the ease of attaching and detaching the liquid dispensing device 1 can be maintained.

[0327] As described above, when the relay board 150 and the cooling fan 59 are configured as a single unit, the case in which the fan drive signal Fp for driving the cooling fan 59 is propagated by the relay board 150 and supplied to the cooling fan 59, and the case in which the fan drive signal Fp for driving the cooling fan 59 is not propagated by the relay board 150 and supplied directly to the cooling fan 59, both reduce the risk of the drive circuit board 700 becoming larger and maintain the ease of attachment and detachment of the liquid dispensing device 1.

[0328] Furthermore, when the relay board 150 and the cooling fan 59 are integrated, and the fan drive signal Fp that drives the cooling fan 59 is propagated by the relay board 150 and supplied to the cooling fan 59, the voltage value of the fan drive signal Fp can be adjusted and noise contained in the fan drive signal Fp can be removed by providing a predetermined circuit on the relay board 150. This improves the driving accuracy of the cooling fan 59 and improves the stability of the operation of the various circuits on the drive circuit board 700. As a result, the ink ejection accuracy from the print head 30 is improved.

[0329] On the other hand, if the relay board 150 and the cooling fan 59 are integrated, and the fan drive signal Fp for driving the cooling fan 59 is not propagated by the relay board 150 but supplied directly to the cooling fan 59, then there is no need to provide wiring for the relay board 150 to propagate the fan drive signal Fp, which makes it possible to miniaturize the relay board 150. As a result, the liquid discharge modules 20 can be arranged in a more compact arrangement, and the liquid discharge device 1 can be further miniaturized.

[0330] 2.2.3.4 Structure of the drive circuit module The structure of the drive circuit module 50 having the drive circuit board 700 and relay board 150 configured as described above will now be explained. Figure 27 shows the drive circuit module 50 along the x2 axis This is a view from the -x2 side. Figure 28 is a view of the drive circuit module 50 along the x2 axis from the +x2 side. Figure 29 is a view of the drive circuit module 50 along the y2 axis from the -y2 side. Figure 30 is a view of the drive circuit module 50 along the z2 axis from the +z2 side. Here, in addition to the drive circuit module 50, a portion of the print head 30 to which the drive circuit module 50 is connected is shown with a dashed line in Figures 27 to 30.

[0331] As shown in Figures 27 and 29, a heat sink 180 is located on the -x2 outer surface of the drive circuit board 700, on the side of the rigid wiring member 710 of the drive circuit board 700 facing surface 724. This heat sink 180 is attached to the rigid wiring member 710. At this time, as shown in Figure 29, a heat conductive member 185 is located between the heat sink 180 and surface 724 of the rigid wiring member 710. This improves the contact between the heat sink 180 and surface 724, allowing heat generated in the rigid wiring member 710 including surface 724 to be efficiently dissipated, and also improves the insulation performance between the heat sink 180 and surface 724. In other words, the heat sink 180 is located closer to the surface 724 of the rigid wiring member 710 than to the surface 723, and closer to the rigid member 722 than to the rigid members 721, 741, and 742 in the direction along the x2 axis, and is attached to the rigid wiring member 710. The heat conduction member 185 is located between the heat sink 180 and the surface 724 of the rigid wiring member 710, and is in contact with both the heat sink 180 and the surface 724 of the rigid wiring member 710. The heat sink 180 and the heat conduction member 185 then release the heat generated by the various circuits provided in the rigid wiring member 710 into the atmosphere.

[0332] Here, the heat sink 180 and the heat conductive member 185 are positioned such that, when the drive circuit module 50 is viewed along the x2 axis from the -x2 side to the +x2 side, at least a portion of them overlap with the drive signal output circuits 52a-1, 52b-1, 52a-2, and 52b-2 provided on the rigid wiring member 710. The drive signal output circuits 52a-1, 52b-1, 52a-2, and 52b-2 are among the circuits provided on the rigid wiring member 710 that generate a large amount of heat. By positioning the heat sink 180 and the heat conductive member 185 in a position that overlaps with these drive signal output circuits 52a-1, 52b-1, 52a-2, and 52b-2, the heat generated in the rigid wiring member 710 can be efficiently released into the atmosphere.

[0333] Furthermore, as shown in Figures 28 and 29, a heat sink 170 is located on the +x2 outer surface of the drive circuit board 700, on the surface 744 side of the rigid wiring member 730 of the drive circuit board 700. This heat sink 170 is attached to the rigid wiring member 730. At this time, as shown in Figure 29, a heat conductive member 175 is located between the heat sink 170 and the surface 744 of the rigid wiring member 730. This improves the contact between the heat sink 170 and the surface 744, allowing heat generated in the rigid wiring member 730 including the surface 744 to be efficiently dissipated, and also improves the insulation performance between the heat sink 170 and the surface 744.

[0334] In other words, the heat sink 170 is located closer to surface 744 of the rigid wiring member 730 than to surface 743, and closer to rigid member 742 than to rigid members 721, 722, and 741 in the direction along the x2 axis, and is attached to the rigid wiring member 730. The heat conduction member 175 is located between the heat sink 170 and surface 744 of the rigid wiring member 730, and is in contact with both the heat sink 170 and surface 744 of the rigid wiring member 730. The heat sink 170 and the heat conduction member 175 then release the heat generated by the various circuits provided in the rigid wiring member 730 into the atmosphere.

[0335] Here, the heat sink 170 and the heat conductive member 175 are such that, when the drive circuit module 50 is viewed along the x2 axis from the +x2 side to the -x2 side, at least a portion of the drive signal output circuits 52a-3, 52b-3, 52a-4, 52b are provided on the rigid wiring member 730. It is positioned to overlap with -4. The drive signal output circuits 52a-3, 52b-3, 52a-4, and 52b-4 are among the circuits provided on the rigid wiring member 730 that generate a large amount of heat. By positioning the heat sink 170 and the heat conductive member 175 to overlap with these drive signal output circuits 52a-3, 52b-3, 52a-4, and 52b-4, the heat generated in the rigid wiring member 730 can be efficiently released into the atmosphere.

[0336] Furthermore, abnormality notification circuits 55a and 55b are located on the surface 744 of the rigid wiring member 730 where the heat sink 170 and the heat conductive member 175 are located. In other words, the abnormality notification circuits 55a and 55b are located on the surface 744 of the rigid wiring member 730 and are provided on the rigid member 742.

[0337] As described above, the abnormality notification circuit 55a lights up, turns off, or blinks based on the abnormality detection result in the abnormality detection circuit 54a, and the abnormality detection circuit 54a detects whether the voltage value of the voltage signal VHV is normal or not. The abnormality notification circuit 55b lights up, turns off, or blinks based on the abnormality detection result in the abnormality detection circuit 54b, and the abnormality detection circuit 54b detects whether the voltage value of the voltage signal VDD, which is generated based on the voltage signal VMV, is normal or not. In other words, the abnormality notification circuit 55a detects whether there is an abnormality in the voltage value of the voltage signal VHV, which functions as the power supply voltage for the drive signal output circuits 52a-1 to 52a-4, 52b-1 to 52b-4 and the print head 30, and the abnormality notification circuit 55b detects whether there is an abnormality in the power supply voltage supplied to the FPGA constituting the ejection control circuit 51. For this reason, the heat sink 170 and the heat conductive member 175 are attached to the rigid wiring member 730 so that the user can visually confirm the lighting status of the abnormality notification circuits 55a and 55b. Furthermore, the abnormality detection circuits 54a and 54b may detect various abnormalities in the drive circuit module 50 in addition to the abnormalities in the voltage signals VHV and VDD described above, and the abnormality notification circuits 55a and 55b may notify various abnormalities in the drive circuit module 50 in addition to the abnormalities in the voltage signals VHV and VDD described above.

[0338] Specifically, as shown in Figures 28 and 29, the heat sink 170 has an opening 172. The opening 172 is positioned to overlap with the abnormality notification circuits 55a and 55b provided on the surface 744 of the rigid wiring member 730 when the heat sink 170 is attached to the rigid wiring member 730. That is, when the drive circuit board 700 is viewed along the direction from the rigid member 742 toward the rigid member 741, the abnormality notification circuits 55a and 55b are positioned to overlap with at least a portion of the opening 172. This reduces the risk of reduced heat dissipation efficiency from the rigid wiring member 730 by the heat sink 170 and the heat conduction member 175, while visually informing the user whether or not there is an abnormality in the drive circuit module 50. Furthermore, the opening 172 only needs to be such that the heat sink 170 and the heat conductive member 175 are not positioned where the abnormality notification circuits 55a and 55b are located when the drive circuit board 700 is viewed in the direction from the rigid member 742 toward the rigid member 741. For example, it may be a notch.

[0339] As mentioned above, the heat sink 170 and the heat conductive member 175 only need to be positioned so that at least a portion of them overlaps with the drive signal output circuits 52a-3, 52b-3, 52a-4, and 52b-4. Therefore, when viewed along the direction from the rigid member 742 to the rigid member 741, the abnormality notification circuits 55a and 55b are positioned so as not to overlap with the drive signal output circuits 52a-3, 52b-3, 52a-4, and 52b-4. This reduces the risk of reduced heat dissipation efficiency of the rigid wiring member 730 by the heat sink 170 and the heat conductive member 175, while visually informing the user whether or not an abnormality has occurred in the drive circuit module 50.

[0340] Furthermore, as shown in Figures 27, 28, and 30, the relay board 150 is located on the +z2 side of the drive circuit board 700 and is electrically connected to the drive circuit board 700 via connector CN2. In this configuration, the relay board 150 is positioned such that its edge 153 aligns with edge 711 of the rigid wiring member 710, its edge 154 aligns with edge 731 of the rigid wiring member 730, and the normal direction of the surface 152 of the relay board 150 intersects with both the normal direction of the surface 723 of the rigid wiring member 710 and the normal direction of the surface 743 of the rigid wiring member 730, and is provided on the +z2 side of the drive circuit board 700. In other words, the relay board 150 is provided so as to constitute one surface of the substantially box shape formed by the drive circuit board 700. In this configuration, the surface 151 of the relay board 150 constitutes the outer surface of the substantially box shape, and the surface 152 of the relay board 150 constitutes the inner surface of the substantially box shape. At this time, the cooling fan 59 fixed to the relay board 150 blows air from the side 151 of the relay board 150 towards the side 152 of the relay board 150, or blows air from the side 152 of the relay board 150 towards the side 151 of the relay board 150. As a result, the cooling fan 59 generates an airflow towards the side 783 of the rigid wiring member 770 in the space inside the roughly box-shaped drive circuit board 700, between the side 723 included in the rigid wiring member 710 of the drive circuit board 700 and the side 743 included in the rigid wiring member 730 of the drive circuit board 700. In other words, the roughly box-shaped drive circuit board 700 has a gas flow path comprising a surface 723 included in the rigid wiring member 710, a surface 743 included in the rigid wiring member 730, and a surface 783 included in the rigid wiring member 770, and the cooling fan 59 provided on the relay board 150 generates airflow in the gas flow path. The cooling fan 59 then cools the drive signal output circuits 52a-1 to 52a-4 and 52b-1 to 52b-4 with this airflow. In other words, the cooling fan 59 generates airflow that cools the drive signal output circuits 52a-1 to 52a-4 and 52b-1 to 52b-4. As a result, even if the drive circuit board 700 is assembled in a roughly box shape, the gas inside the roughly box shape circulates, further improving the cooling efficiency of the drive signal output circuits 52a-1 to 52a-4 and 52b-1 to 52b-4 located inside the roughly box shape.

[0341] In this case, it is preferable that the capacitor C7a provided on the rigid wiring member 710 and the capacitor C7b provided on the rigid wiring member 730 are located near the cooling fan 59. Capacitors C7a and C7b, which are configured as electrolytic capacitors, have a larger component height and a smaller contact area with the drive circuit board 700 compared to the integrated circuit 500 and transistors M1 and M2, which are configured as surface mount components. Therefore, the amount of heat generated by capacitors C7a and C7b released to the drive circuit board 700 is small. By arranging such capacitors C7a and C7b near the cooling fan 59, capacitors C7a and C7b can be efficiently cooled by the airflow generated by the cooling fan 59. This improves the cooling efficiency of capacitors C7a and C7b and reduces the temperature rise of the drive circuit module 50.

[0342] In other words, the shortest distance between capacitor C7a and cooling fan 59 is smaller than the shortest distance between transistors M1 and M2 and cooling fan 59, and the shortest distance between capacitor C7b and cooling fan 59 is smaller than the shortest distance between transistors M1 and M2 and cooling fan 59, which improves the cooling efficiency of capacitors C7a and C7b, and as a result, reduces the temperature rise of the drive circuit module 50.

[0343] Furthermore, as shown in Figures 27, 28, and 29, an opening plate 160 is located on the -y2 side of the assembled drive circuit board 700. The opening plate 160 is a plate-shaped member extending in the x2z2 plane, and openings 161, 162, 163, and 164 are formed in the opening plate 160 that penetrate the plate-shaped member. As shown in Figure 29, the opening plate 160 constitutes one side of the roughly box-shaped drive circuit board 700 in the assembled state. Also, when viewed along the normal direction of the plate-shaped member opening plate 160, opening 161 overlaps with at least a portion of the inductor L1 of the drive signal output circuit 52a-1 and at least a portion of the inductor L1 of the drive signal output circuit 52a-2, and opening 162 overlaps with at least a portion of the inductor L1 of the drive signal output circuit 52b-4 and the inductor L1 of the drive signal output circuit 52b-3 The opening 163 overlaps with at least a portion of capacitor C7a, and the opening 164 overlaps with at least a portion of capacitor C7b.

[0344] The airflow generated inside the assembled drive circuit board 700 by the cooling fan 59 passes through the openings 161, 162, 163, and 164. At this time, the airflow velocity inside the drive circuit board 700 is fastest near the openings 161, 162, 163, and 164. Since the inductors L1 and capacitors C7a and C7b of the drive signal output circuits 52a-1, 52a-2, 52b-4, and 52b-3, which have large component heights, are located near the openings 161, 162, 163, and 164 where the airflow velocity is high, the inductors L1 and capacitors C7a and C7b can be efficiently cooled by the airflow generated by the cooling fan 59.

[0345] Electronic components with a large component height, such as the inductor L1 and capacitors C7a and C7b in the drive signal output circuit 52, have a smaller contact area with the drive circuit board 700 compared to surface-mount components such as the integrated circuit 500 and transistors M1 and M2. Therefore, less heat is released to the drive circuit board 700. Consequently, the heat sinks 170 and 180 attached to the drive circuit board 700 may not be able to adequately cool the inductor L1 and capacitors C7a and C7b in the drive signal output circuit 52, which have a large component height.

[0346] By placing the tall inductor L1 and capacitors C7a and C7b near openings 161, 162, 163, and 164 where the airflow velocity is high, even the tall inductor L1 and capacitors C7a and C7b can be efficiently cooled by the airflow generated by the cooling fan 59, and as a result, the temperature rise of the drive circuit module 50 is reduced.

[0347] In this case, it is preferable that the opening plate 160 is arranged such that the inductor L1 of the drive signal output circuit 52a-1 does not cover the entire opening 161, the inductor L1 of the drive signal output circuit 52b-4 does not cover the entire opening 162, the capacitor C7a does not cover the entire opening 163, and the capacitor C7b does not cover the entire opening 164.

[0348] In other words, it is preferable that the opening plate 160 is positioned such that, when viewed along the normal direction of the plate-shaped opening plate 160, at least a portion of the opening 161 does not overlap with the inductor L1 of the drive signal output circuit 52a-1, at least a portion of the opening 162 does not overlap with the inductor L1 of the drive signal output circuit 52b-4, at least a portion of the opening 163 does not overlap with the capacitor C7a, and at least a portion of the opening 164 does not overlap with the capacitor C7b.

[0349] This reduces the risk that the airflow passing through openings 161, 162, 163, and 164 will be obstructed by the inductor L1 of drive signal output circuit 52a-1, the inductor L1 of drive signal output circuit 52b-4, capacitor C7a, and capacitor C7b, thereby reducing the risk of localized temperature rise in the drive circuit module 50.

[0350] As described above, the drive circuit module 50 includes a drive circuit board 700, a relay board 150, an opening plate 160, and heat sinks 170 and 180 attached to the drive circuit board 700. The drive circuit module 50 operates based on various signals input via the relay board 150 to generate various control signals for controlling the operation of the print head 30, and outputs them to the print head 30 via the connector CN1.

[0351] The size of this drive circuit module 50 when viewed along the z2 axis is smaller than the size of the print head 30 when viewed from connector CN1b toward the ejection unit 600. As shown in Figure 30, with connector CN1a attached to the print head 30, the drive circuit module 50 is located inside the print head 30. That is, in the drive circuit board 700 included in the drive circuit module 50, the size of rigid member 781 and rigid member 782 when viewed along the direction from rigid member 781 to rigid member 782 is smaller than the size of the print head 30 when viewed along the direction from connector CN1b to ejection section 600. With the drive circuit board 700 electrically connected to the print head 30 by connectors CN1a and CN1b, the drive circuit board 700 included in the drive circuit module 50 is located inside the print head 30.

[0352] As a result, when attaching the liquid ejection module 20, which has a drive circuit board 700 and a print head 30 electrically connected to the drive circuit board 700, to the liquid ejection device 1, the size of the drive circuit board 700, which has many circuit components, reduces the likelihood of constraints on the placement of the liquid ejection module 20. Consequently, a more compact arrangement of the liquid ejection module 20 in the liquid ejection device 1 becomes possible, reducing the likelihood of the liquid ejection device 1 becoming larger.

[0353] Furthermore, as described above, in this embodiment, the size of the rigid wiring member 710 when the drive circuit board 700 is viewed along the z1 axis is approximately equal to the size of the rigid wiring member 730 when the drive circuit board 700 is viewed along the z1 axis, the size of the rigid wiring member 750 when the drive circuit board 700 is viewed along the z1 axis is smaller than the size of the rigid wiring member 710 and the rigid wiring member 730 when the drive circuit board 700 is viewed along the z1 axis, and the size of the rigid wiring member 770 when the drive circuit board 700 is viewed along the z1 axis is smaller than the size of the rigid wiring member 710 and the rigid wiring member 730 when the drive circuit board 700 is viewed along the z1 axis. In other words, when viewing the drive circuit board 700 along the direction from rigid member 781 to rigid member 782, the size of rigid member 781 is smaller than the size of rigid member 721 when viewed along the direction from rigid member 721 to rigid member 722, and also smaller than the size of rigid member 741 when viewed along the direction from rigid member 741 to rigid member 742.

[0354] This makes it possible to increase the mounting area of ​​electronic components on the drive circuit board 700 of the liquid ejection module 20. As a result, even if the number of components mounted on the drive circuit board 700 increases due to an increase in the number of ejection units 600 of the print head 30, it becomes possible to arrange the liquid ejection modules 20 more densely in the liquid ejection device 1, reducing the risk of the liquid ejection device 1 becoming larger.

[0355] Here, the drive circuit module 50 is an example of a substrate unit. Also, the piezoelectric element 60 included in the discharge module 32-1 is an example of a first piezoelectric element, the discharge section 600 included in the discharge module 32-1 is an example of a first discharge section, the piezoelectric element 60 included in the discharge module 32-1 is an example of a second piezoelectric element, and the discharge section 600 included in the discharge module 32-1 is an example of a second discharge section. Furthermore, connector CN1b is an example of a first connector, connector CN1a is an example of a second connector, connector CN3a is an example of a first fixing member, and connector CN3b is an example of a second fixing member. Also, the drive circuit board 700 is an example of a wiring board, the electronic components constituting various circuits provided on the drive circuit board 700 are an example of multiple circuit components, the rigid members 721, 722, 741, 742, 761, 762, 781, 782 included in the drive circuit board 700 are an example of multiple rigid members, and the flexible wiring member 790 is an example of a flexible member. Furthermore, rigid member 721 is an example of a first rigid member, and rigid member 741 is a second rigid member This is an example of a component, where rigid member 781 is an example of a third rigid member, rigid member 782 is an example of a fourth rigid member, rigid member 722 is an example of a fifth rigid member, rigid member 742 is an example of a sixth rigid member, surface 723 of rigid member 721 is an example of a first surface, surface 743 of rigid member 741 is an example of a second surface, surface 783 of rigid member 781 is an example of a third surface, surface 784 of rigid member 782 is an example of a fourth surface, surface 724 of rigid member 722 is an example of a fifth surface, and surface 744 of rigid member 742 is an example of a sixth surface. Furthermore, surface 791 of the flexible wiring member 790 is an example of a first surface, surface 792 of the flexible wiring member 790 is an example of a second surface, region 701 of the flexible wiring member 790 is an example of a first region, region 705 of the flexible wiring member 790 is an example of a second region, region 707 of the flexible wiring member 790 is an example of a third region, at least one of regions 702 and 704 of the flexible wiring member 790 is an example of a fourth region, and region 706 of the flexible wiring member 790 is an example of a fifth region. Furthermore, a drive signal output circuit 52a-1 provided on the drive circuit board 700 is an example of a first drive circuit, and a drive signal VOUT based on the drive signal COMA1 output by the drive signal output circuit 52a-1 is an example of a first drive signal, and a trapezoidal waveform Adp1 or trapezoidal waveform Adp2 of the drive signal COMA1 is an example of a second drive circuit, and a drive signal VOUT based on the drive signal COMA3 output by the drive signal output circuit 52a-3 is an example of a second drive signal, and a trapezoidal waveform Adp1 or trapezoidal waveform Adp2 of the drive signal COMA3 is an example of a print head control signal, and one of the clock signal SCK, differential print data signal Dp, or differential drive data signal Dd is an example of a print head control signal.

[0356] 3. Effects As described above, the liquid ejection device 1 of this embodiment comprises a print head 30 for ejecting ink and a drive circuit board 700 electrically connected to the print head 30. The drive circuit board 700 also includes a rigid wiring member 710 including rigid members 721, 722 on which a plurality of circuit components are provided, a rigid wiring member 730 including rigid members 741, 742, a rigid wiring member 750 including rigid members 761, 762, and a rigid wiring member 770 including rigid members 781, 782, and a flexible wiring member 790 which is more flexible than the rigid wiring members 710, 730, 750, and 770. Then, by stacking the rigid members 721, 722, 741, 742, 761, 762, 781, and 782 on the flexible wiring member 790, the rigid wiring members 710, 730, 750, and 770 are electrically connected to each other by the flexible wiring member 790.

[0357] In this configuration, the rigid wiring member 710 and the rigid wiring member 730, specifically the rigid member 721 included in the rigid wiring member 710 and the rigid member 741 included in the rigid wiring member 730, are arranged such that their surfaces 723 and 743 face each other when the flexible wiring member 790 is bent in regions 702 and 704. This reduces the area occupied by the drive circuit board 700, which is electrically connected to the print head 30, in the liquid ejection module 20, enabling a more compact arrangement of the liquid ejection modules 20 and allowing for a smaller liquid ejection device 1 equipped with multiple liquid ejection modules 20.

[0358] Furthermore, the rigid wiring member 770 of the drive circuit board 700 is positioned such that the normal direction of the surface 783 of the rigid member 781 included in the rigid wiring member 770 intersects with both the normal direction of the surface 723 of the rigid member 721 included in the rigid wiring member 710 and the normal direction of the surface 743 of the rigid member 741 included in the rigid wiring member 730. In other words, the rigid wiring member 770 is positioned to cover at least a portion of the area between the rigid wiring member 710 and the rigid wiring member 730, which are located opposite each other. This reduces the risk of ink mist entering the area between the rigid wiring member 710 and the rigid wiring member 730. As a result, ink mist is prevented from entering the various circuits provided on the drive circuit board 700. The risk of ink adhering is reduced, the stability of the operation of the various circuits provided on the drive circuit board 700 is improved, and the stability of the operation of the print head 30, which operates based on the output signals of the various circuits provided on the drive circuit board 700, is also improved. Therefore, the ejection accuracy of the ink ejected from the print head 30 is improved.

[0359] Furthermore, the rigid wiring member 770 is provided with a connector CN1a that is electrically connected to the print head 30. Connector CN1a is mated with connector CN1b provided on the print head 30, thereby electrically connecting the drive circuit board 700 and the print head 30. In other words, the drive circuit board 700 and the print head 30 are electrically connected by connector CN1, which is a BtoB connector. This reduces the impedance of the propagation path through which the signal output from the drive circuit board 700 and input to the print head 30 is propagated. As a result, the accuracy of the signal input to the print head 30 is improved, and the ejection accuracy of the ink ejected from the print head 30 is improved.

[0360] In the drive circuit board 700 configured as described above, the wiring wh2 through which the circuit composed of various circuit components provided on the rigid members 721, 722, 741, 742, 761, 762, 781, 782, and the voltage signal VHV as the power supply voltage of the drive signal selection circuit 200 of the print head 30 propagates is continuously provided in the flexible wiring member 790 across the region 701 where the rigid members 721, 722 are stacked, the region 703 where the rigid members 761, 762 are stacked, the region 705 where the rigid members 741, 742 are stacked, the region 702 located between region 701 and region 703, and the region 704 located between region 703 and region 705. In other words, the voltage signal VHV propagates through the wiring wh2 without going through via wiring and is supplied to rigid wiring member 710, rigid wiring member 730, and rigid wiring member 750. This reduces the risk of signals from different wiring layers being superimposed as noise on the voltage signal VHV supplied to rigid wiring member 710, rigid wiring member 730, and rigid wiring member 750. In other words, the accuracy of the voltage signal VHV supplied to the various circuits provided on rigid wiring member 710, rigid wiring member 730, and rigid wiring member 750 is improved, and the operational stability of the various circuits provided on rigid wiring member 710, rigid wiring member 730, and rigid wiring member 750 is improved. As a result, the accuracy of the output signals output by the various circuits provided on the rigid wiring member 710, the various circuits provided on the rigid wiring member 730, and the various circuits provided on the rigid wiring member 750 is improved, the operation of the print head 30 which operates based on these output signals becomes more stable, and the accuracy of the ink ejection from the print head 30 is improved.

[0361] Furthermore, in the liquid dispensing device 1 of this embodiment, the wiring wh2 through which the voltage signal VHV propagates is oriented from region 701 to region 705 of the flexible wiring member 790, and is provided continuously and linearly across regions 701, 703, and 705. The voltage signal VHV functions as the power supply voltage for the circuit composed of various circuit components provided on the rigid members 721, 722, 741, 742, 761, 762, 781, and 782, and for the drive signal selection circuit 200 of the print head 30. Therefore, a large current flows through the wiring wh2 through which the voltage signal VHV propagates. By making such wiring wh2 linear, the risk of bias in the current density based on the voltage signal VHV propagating through wiring wh2 is reduced, and the risk of fluctuations in the voltage value of the voltage signal VHV is reduced. This improves the accuracy of the voltage signal VHV supplied to the various circuits provided in the rigid wiring members 710, 730, and 750, and improves the operational stability of the various circuits provided in the rigid wiring members 710, 730, and 750. As a result, the accuracy of the output signals output by the various circuits provided in the rigid wiring members 710, 730, and 750 is further improved, and the operation of the print head 30, which operates based on these output signals, becomes even more stable, and the ink ejected from the print head 30 is improved. Output accuracy is further improved. Here, "linear" includes the fact that, in the unfolded state of the drive circuit board 700, the wiring wh2 is provided along a virtual straight line from region 701 to region 705.

[0362] Furthermore, rigid member 721 of rigid wiring member 710 and rigid member 741 of rigid wiring member 730 are provided with drive signal output circuits 52a-1 to 52a-4 and 52b-1 to 52b-4. Drive signal output circuits 52a-1 to 52a-4 and 52b-1 to 52b-4 generate drive signals COMA1 to COMA4 and COMB1 to COMB4 by performing Class D amplification based on a voltage signal VHV. By improving the accuracy of the voltage signal VHV input to rigid members 721 and 741, which are provided with such drive signal output circuits 52a-1 to 52a-4 and 52b-1 to 52b-4, the accuracy of the drive signals COMA1 to COMA4 and COMB1 to COMB4 output by drive signal output circuits 52a-1 to 52a-4 and 52b-1 to 52b-4 is also improved. As a result, the accuracy of ink ejection from the print head 30 is further improved.

[0363] Furthermore, by making the size of the rigid wiring member 770, which has a connector CN1a electrically connected to the connector CN1b of the print head 30, when viewed along the direction from rigid member 781 to rigid member 782, smaller than the size of the print head 30 when viewed along the direction from connector CN1b to ejection unit 600, it becomes possible to arrange the liquid ejection module 20, including the drive circuit board 700 and the print head 30, more compactly. As a result, the liquid ejection device 1, which has multiple liquid ejection modules 20, can be further miniaturized.

[0364] In this configuration, the drive circuit board 700 has connectors CN3a and CN3b, with connector CN3a provided on the rigid wiring member 710 and connector CN3b provided on the rigid wiring member 770. In the assembled state, the drive circuit board 700 maintains a roughly box shape when connectors CN3a and CN3b are fitted together. This eliminates the need for a retaining member to maintain the shape of the assembled drive circuit board 700, enabling further miniaturization of the drive circuit module 50, including the drive circuit board 700. As a result, a more compact arrangement of the liquid discharge module 20, including the drive circuit module 50, becomes possible, and consequently, the liquid discharge device 1, equipped with multiple liquid discharge modules 20, can be further miniaturized.

[0365] Furthermore, the connectors CN3a and CN3b on the drive circuit board 700 electrically connect the rigid wiring member 710 and the rigid wiring member 770 when mated together. This makes it possible to propagate the signal generated by the rigid wiring member 710 to the rigid wiring member 770 without going through the rigid wiring members 730 and 750. As a result, the number of wiring patterns provided on the drive circuit board 700 can be reduced, enabling further miniaturization of the drive circuit board 700. Consequently, a more compact arrangement of the liquid discharge module 20, including the drive circuit module 50, becomes possible, and as a result, the liquid discharge device 1 equipped with multiple liquid discharge modules 20 can be further miniaturized.

[0366] At this time, the clock signal SCK and differential printing data signal Dpt output by the ejection control circuit 51 included in the FPGA provided on the drive circuit board 700 are input to the print head 30 via connectors CN1a, CN1b and rigid wiring member 770. The clock signal SCK and differential printing data signal Dpt are signals with small voltage values, and by propagating such a clock signal SCK and differential printing data signal Dpt to the rigid wiring member 770 via connectors CN3a and CN3b without going through rigid wiring members 730 and 750, the signal accuracy of the clock signal SCK and differential printing data signal Dpt input to the print head 30 is improved. As a result, the ink ejection accuracy from the print head 30 is improved. Further improvement.

[0367] Furthermore, in the drive circuit module 50, rigid wiring members 710 and 730 included in the drive circuit board 700 are positioned so that their surfaces 723 and 743 face each other. A heat sink 180 is located on surface 724 of rigid wiring member 710, and a heat sink 170 is located on surface 744 of rigid wiring member 730. In addition, a cooling fan 59 generates airflow in the area between the rigid wiring members 710 and 730 that face each other. As a result, the drive circuit board 700 is cooled from both sides by the heat dissipation effect of the airflow generated by the cooling fan 59 and the heat release effect of the heat sinks 170 and 180. This improves the heat release efficiency of the drive circuit board 700, or cooling efficiency, and further improves the operational stability of the various circuits provided on the drive circuit board 700. As a result, the signal accuracy of the output signal output by the drive circuit board 700 is improved, and the ink ejection accuracy from the print head 30, which ejects ink based on the output signals of various circuits provided on the drive circuit board 700, is also improved.

[0368] At this time, a heat conductive member 185 with insulating properties is located between the heat sink 180 and the surface 724 of the rigid wiring member 710, and a heat conductive member 175 with insulating properties is located between the heat sink 170 and the surface 744 of the rigid wiring member 730. The heat conductive member 185 is in contact with both the surface 724 and the heat sink 180, and the heat conductive member 175 is in contact with both the surface 744 and the heat sink 170. As a result, the adhesion and insulating properties between the heat sink 170 and the rigid wiring member 730 are improved, and the adhesion and insulating properties between the heat sink 180 and the rigid wiring member 710 are improved. As a result, the heat dissipation performance of the heat sinks 170 and 180 is further improved, the heat dissipation efficiency of the drive circuit board 700, and thus the cooling efficiency are further improved. In addition, the insulation performance between the heat sinks 170 and 180 and the drive circuit board 700 is improved, and the stability of the operation of the various circuits provided on the drive circuit board 700 is further improved.

[0369] Furthermore, in the drive circuit board 700 of this embodiment, the rigid wiring member 770 of the drive circuit board 700 is positioned such that the normal direction of the surface 783 of the rigid member 781 included in the rigid wiring member 770 intersects with both the normal direction of the surface 723 of the rigid member 721 included in the rigid wiring member 710 and the normal direction of the surface 743 of the rigid member 741 included in the rigid wiring member 730, thereby forming part of the gas flow path of the gas generated by the cooling fan 59. At this time, the cooling fan 59 generates an airflow toward the rigid wiring member 770. As a result, the cooling fan 59 can also cool the electronic components that constitute the circuit provided on the rigid wiring member 770. This further improves the stability of the operation of the various circuits provided on the drive circuit board 700.

[0370] Furthermore, in the drive circuit module 50 configured as described above, drive signal output circuits 52a-1, 52a-2, 52b-1, and 52b-2 are provided on the surface 723 of the rigid wiring member 710 to output drive signals COMA1, COMA2, COMB1, and COMB2, and drive signal output circuits 52a-3, 52a-4, 52b-3, and 52b-4 are provided on the surface 743 of the rigid wiring member 730 to output drive signals COMA3, COMA4, COMB3, and COMB4. Because the drive signal output circuits 52a-1 to 52a-4 and 52b-1 to 52b-4 supply drive signals COMA1 to COMA4 and COMB1 to COMB4 based on the voltage signal VHV to each of the multiple discharge units 600, a large amount of heat is generated. Even when the drive circuit board 700 is equipped with drive signal output circuits 52a-1 to 52a-4 and 52b-1 to 52b-4 that generate a large amount of heat, the drive circuit board 700 of this embodiment is cooled by both the heat dissipation effect of the airflow generated by the cooling fan 59 and the heat release effect of the heat sinks 170 and 180, thereby further improving the operational stability of the drive signal output circuits 52a-1 to 52a-4 and 52b-1 to 52b-4.

[0371] Furthermore, electrolytic capacitors C7a and C7b are provided on the drive circuit board 700. Capacitors C7a and C7b are positioned on the drive circuit board 700 such that the shortest distance between capacitors C7a and C7b and the cooling fan 59 is shorter than the shortest distance between transistors M1 and M2 included in the drive signal output circuit 52 and the cooling fan 59. The component height of electrolytic capacitors C7a and C7b is greater than that of surface-mount transistors M1 and M2, and therefore, cooling is achieved via the drive circuit board 700, with little cooling effect from heat dissipation by heat sinks 170 and 180. By placing such capacitors C7a and C7b near the cooling fan 59, capacitors C7a and C7b can be cooled. As a result, the operational stability of the various circuits provided on the drive circuit board 700 is further improved.

[0372] Furthermore, the drive circuit module 50 has a plate-shaped opening plate 160 having openings 161 and 162 through which the airflow generated by the cooling fan 59 passes. The opening plate 160 is positioned such that, when viewed along the direction normal to the opening plate 160, opening 161 overlaps with at least a portion of the inductor L1 of the drive signal output circuit 52a-1, and opening 162 overlaps with at least a portion of the inductor L1 of the drive signal output circuit 52a-1. When the airflow generated by the cooling fan 59 passes through openings 161 and 162, the velocity of the airflow increases. By placing the inductor L1 included in the drive signal output circuit 52, which has a large component height, in this region where the velocity of the airflow generated by the cooling fan 59 increases, the cooling efficiency of the inductor L1 can be increased, and the stability of the operation of the various circuits provided on the drive circuit board 700 can be improved. As a result, the signal accuracy of the output signal output by the drive circuit board 700 is improved, and the ink ejection accuracy from the print head 30, which ejects ink based on the output signals of various circuits provided on the drive circuit board 700, is also improved.

[0373] Furthermore, because the airflow generated by the cooling fan 59 can increase its velocity as it passes through the openings 161 and 162, even a small cooling fan 59 can provide sufficient cooling capacity. As a result, the risk of reduced ink ejection accuracy from the print head 30 due to vibrations that may occur when the cooling fan 59 is driven is reduced.

[0374] Furthermore, the drive circuit module 50 has an intermediate board 150 on its surface 151, to which an FFC cable 21 carrying voltage signals VHV and VMV and an FFC cable 22 carrying a clock signal SCK, a differential printing data signal Dp, and a differential drive data signal Dd are electrically connected. On the opposite surface 152 from surface 151, there is an intermediate board 150 to which a connector CN2a electrically connected to the drive circuit board 700 is provided. In other words, signals propagated through the FFC cables 21 and 22 are input to the intermediate board 150 and output to the drive circuit board 700 via connector CN2a. This allows the drive circuit board 700 to be attached to and detached from the liquid dispensing device 1 simply by attaching and detaching connectors CN2a and CN2b, thereby improving the efficiency of maintenance, replacement, and assembly work on the drive circuit board 700.

[0375] Furthermore, since the drive circuit board 700 can be attached to and detached from the liquid dispensing device 1 simply by attaching and detaching connectors CN2a and CN2b, the space required for such attachment and detachment can be reduced. This allows for a more compact arrangement of the liquid dispensing modules 20, and as a result, further miniaturization of the liquid dispensing device 1 becomes possible.

[0376] Furthermore, a cooling fan 59 is fixed to the relay board 150. This allows for the attachment and detachment of the cooling fan 59 along with the attachment and detachment of the drive circuit board 700 to the liquid dispensing device 1. As a result, there is no need to provide wiring on the drive circuit board 700 for the fan drive signal Fp that drives the cooling fan 59, making it possible to miniaturize the drive circuit board 700.

[0377] Furthermore, the drive circuit module 50 has a temperature detection circuit 56 that detects the ambient temperature of the drive circuit module 50, which is the internal ambient temperature of the drive circuit module 50. The control unit 2 and the head control circuit 12 control the operation of the drive circuit module 50 and the print head 30 based on the ambient temperature detected by the temperature detection circuit 56. In other words, the liquid ejection device 1 of this embodiment does not individually detect the temperatures of the various circuits in the drive circuit module 50, but rather the temperature detection circuit 56 detects the internal ambient temperature of the drive circuit module 50, which changes according to the operating state of the drive circuit module 50, as the ambient temperature. The control unit 2 and the head control circuit 12 then control the operation of the drive circuit module 50 and the print head 30 based on the ambient temperature detected by the temperature detection circuit 56. As a result, it is not necessary to individually provide temperature detectors such as sensor elements on the electronic components of the drive circuit module 50, and the drive circuit module 50 can be miniaturized. As a result, the liquid ejection modules 20 can be arranged more densely, and the liquid ejection device 1 can be further miniaturized.

[0378] Such a temperature detection circuit 56 is provided on a rigid wiring member 750 located between a rigid wiring member 710 on the drive circuit board 700, which is provided with drive signal output circuits 52a-1, 52a-2, 52b-1, and 52b-2, and a rigid wiring member 730 on which drive signal output circuits 52a-3, 52a-4, 52b-3, and 52b-4 are provided. This reduces the risk that the contribution of temperature changes that may occur in the drive signal output circuits 52a-1 to 52a-4 and 52b-1 to 52b-4, which generate a large amount of heat, to the ambient temperature detected by the temperature detection circuit 56 will become extremely high. In other words, the detection accuracy of the ambient temperature detected by the temperature detection circuit 56 is improved. Consequently, the accuracy of the operation control of the drive circuit module 50 and the print head 30 by the control unit 2 and the head control circuit 12 based on the ambient temperature detected by the temperature detection circuit 56 is improved, and the ejection accuracy of the ink ejected from the print head 30 is improved.

[0379] Furthermore, in the drive circuit board 700, the drive signal output circuits 52a-1 and 52b-1 provided on the rigid wiring member 710 each have an integrated circuit 500, transistors M1 and M2, and an inductor L1, and are positioned so that at least a portion of the drive signal output circuits 52a-1 and 52b-1 overlap along the direction from edge 713 to edge 714. At this time, the integrated circuit 500 of the drive signal output circuit 52a-1 and the integrated circuit 500 of the drive signal output circuit 52b-1 are arranged so as not to overlap along the direction from edge 713 to edge 714. This reduces the risk of localized high-temperature areas occurring on the drive circuit board 700 due to the concentration of heat generated in the drive signal output circuit 52a-1 and the drive signal output circuit 52b-1.

[0380] Furthermore, in the drive circuit board 700 of this embodiment, the drive signal output circuit 52b-4 provided on the rigid wiring member 730 has an integrated circuit 500, transistors M1 and M2, and an inductor L1. Along the x2 axis, the drive signal output circuit 52a-1 and the drive signal output circuit 52b-4 are positioned so that at least a portion of them overlap, while along the x2 axis, the integrated circuit 500 of the drive signal output circuit 52a-1 and the integrated circuit 500 of the drive signal output circuit 52b-4 are arranged so that they do not overlap. As a result, even in the assembled state of the drive circuit board 700, the risk of localized high-temperature areas occurring on the drive circuit board 700 due to the concentration of heat generated in the drive signal output circuit 52a-1 and the drive signal output circuit 52b-4 is reduced.

[0381] In other words, in the liquid ejection device 1 of this embodiment, the drive signal output circuits 52a-1 to 52a-4 and 52b-1 to 52b-4, which generate a large amount of heat, are arranged in a staggered pattern. This reduces the risk of localized heat concentration on the drive circuit board 700, and as a result, the waveform accuracy of the drive signals COMA1 to COMA4 and COMB1 to COMB4 output by the drive circuit board 700 to the print head 30 is improved, and the ejection accuracy of the ink ejected from the print head 30 is improved.

[0382] In this case, the transistors M1 and M2 of the drive signal output circuit 52a-1 and the transistors M1 and M2 of the drive signal output circuit 52b-1 are arranged so as not to overlap along the direction from side 713 to side 714, and the transistors M1 and M2 of the drive signal output circuit 52a-1 and the transistors M1 and M2 of the drive signal output circuit 52b-4 are arranged so as not to overlap along the x2 axis, thereby further reducing the concentration of heat on the drive circuit board 700. Furthermore, by arranging the inductor L1 of the drive signal output circuit 52a-1 and the inductor L1 of the drive signal output circuit 52b-1 so as not to overlap along the direction from side 713 to side 714, and by arranging the inductor L1 of the drive signal output circuit 52a-1 and the inductor L1 of the drive signal output circuit 52b-4 so as not to overlap along the x2 axis, the concentration of heat on the drive circuit board 700 can be further reduced.

[0383] Furthermore, a capacitor C53, which is an electrolytic capacitor for stabilizing the voltage value of the reference voltage signal VBS, is provided on surface 783 of the rigid wiring member 770 of the drive circuit board 700, and a connector CN1a that is electrically connected to the print head 30 is provided on surface 784 of the rigid wiring member 770 of the drive circuit board 700. In other words, the voltage value of the reference voltage signal VBS is stabilized in the rigid wiring member 770 on which the connector CN1a that is electrically connected to the print head 30 is provided. As a result, the stability of the voltage value of the reference voltage signal VBS supplied to the print head 30 is improved, the displacement accuracy of the piezoelectric element 60 of the print head 30 is improved, and the ejection accuracy of the ink ejected by the displacement of the piezoelectric element 60 is also improved.

[0384] Furthermore, the reference voltage signal VBS supplied to the electrodes 612 of the piezoelectric element 60 is supplied in common to the piezoelectric element 60 supplied with drive signals VOUT based on drive signals COMA1, COMB1, the piezoelectric element 60 supplied with drive signals VOUT based on drive signals COMA2, COMB2, the piezoelectric element 60 supplied with drive signals VOUT based on drive signals COMA3, COMB3, and the piezoelectric element 60 supplied with drive signals VOUT based on drive signals COMA4, COMB4. Such a reference voltage signal VBS is supplied from a single reference voltage signal output circuit 530. As a result, even piezoelectric elements 60 supplied with drive signals VOUT based on different drive signals COM can be driven based on a common reference potential, improving the displacement accuracy of the piezoelectric element 60 of the print head 30, and improving the ejection accuracy of the ink ejected by the displacement of the piezoelectric element 60.

[0385] Furthermore, the drive circuit module 50 has abnormality notification circuits 55a and 55b, which are located on the surface 744 of the rigid wiring member 730 of the drive circuit board 700, specifically on the surface 744 of the rigid member 742 included in the rigid wiring member 730. In other words, the abnormality notification circuit 55 is located on the outer surface of the drive circuit board 700 in its assembled state, which is configured in a roughly box shape. This allows the user to visually confirm any abnormalities in the liquid discharge module 20, thereby improving the reliability of the liquid discharge module 20 and the liquid discharge device 1.

[0386] At this time, the heat sink 170 is located on the surface 744 of the rigid wiring member 730 of the drive circuit board 700, specifically on the surface 744 of the rigid member 742 included in the rigid wiring member 730, as described above. On the surface 744 of the rigid wiring member 730 of the drive circuit board 700, specifically on the surface 744 of the rigid member 742 included in the rigid wiring member 730, the abnormality notification circuits 55a and 55b are positioned so as not to overlap with the drive signal output circuit 52, along the direction from the rigid member 742 to the rigid member 741, and the heat sink 170 is positioned so as to overlap with the drive signal output circuit 52. This allows for the dissipation of heat generated by the drive signal output circuit 52 without impairing the visibility of the abnormality notification circuits 55a and 55b. As a result, the accuracy of the signals output by the drive circuit board 700 is improved, and the liquid The reliability of the discharge module 20 and the liquid discharge device 1 can be improved.

[0387] Furthermore, the heat sink 170 has an opening 172, and the abnormality notification circuits 55a and 55b are positioned so as to overlap with the opening 172 in the direction from the rigid member 742 toward the rigid member 741. This allows for efficient dissipation of heat generated by the drive signal output circuit 52 without impairing the visibility of the abnormality notification circuits 55a and 55b. As a result, the accuracy of the signals output by the drive circuit board 700 is improved, and the reliability of the liquid discharge module 20 and the liquid discharge device 1 is enhanced.

[0388] 4. Variations Next, a modified liquid dispensing device 1 will be described. Figure 31 is a diagram showing the schematic configuration of the modified liquid dispensing device 1. In the liquid dispensing device 1 described above, the drive circuit module 50 of the liquid dispensing module 20 has a cooling fan 59, and the cooling fan 59 generates an airflow in the gas flow path composed of the rigid wiring members 710, 730, 750, and 770 of the drive circuit board 700, thereby cooling the drive circuit board 700. However, in the modified liquid dispensing device 1, instead of or in addition to the cooling fan 59, there is a compressor CP, and the airflow generated by the operation of the compressor CP is supplied to the gas flow path composed of the rigid wiring members 710, 730, 750, and 770 of the drive circuit board 700, thereby cooling the drive circuit board 700.

[0389] In other words, the modified liquid ejection device 1 comprises a print head 30 that ejects ink as an example of a liquid, a drive circuit module 50 electrically connected to the print head 30, a compressor CP that sends out compressed air AR, and a tube TB connecting the drive circuit module 50 and the compressor CP. The compressor CP supplies compressed air AR via the tube TB to the region where the surface 723 of the rigid wiring member 710 included in the drive circuit board 700, which is the surface 723 of the rigid member 721, and the surface 743 of the rigid wiring member 730, which is the surface 743 of the rigid member 741, face each other.

[0390] As shown in Figure 31, the compressor CP is provided separately from the head unit 3. In this case, the compressor CP is provided outside the printing area where the head unit 3 ejects ink onto the medium P to form an image, preferably in a space isolated from the printing area. When the compressor CP is driven, it draws in air from the space, compresses it, and outputs it as compressed air AR. The compressed air AR output by the compressor CP is then supplied to the liquid ejection module 20 via the tube TB.

[0391] Figure 32 is an exploded perspective view showing an example of the structure of a modified liquid discharge module 20. As shown in Figure 32, the tube TB is connected to a through hole 159 that penetrates surfaces 151 and 152 formed on the relay substrate 150. This supplies compressed air AR to the liquid discharge module 20. The compressed air AR is then supplied through the through hole 159 of the relay substrate 150 to the region where the surface 723 of the rigid wiring member 710 of the drive circuit board 700 of the drive circuit module 50, which is the surface 723 of the rigid member 721, and the surface 743 of the rigid wiring member 730, which is the surface 743 of the rigid member 741, face each other. Even with the modified liquid discharge device 1 configured as described above, the same effects and advantages as in the embodiment described above are achieved.

[0392] Furthermore, in the modified liquid ejection device 1, as mentioned above, the compressor CP is located in a space isolated from the printing area. As a result, the compressed air AR output by the compressor CP does not contain ink mist, which is part of the ink ejected by the print head 30 onto the medium P, nor dust such as paper dust or feathers that may be generated during the transport of the medium P. Therefore, the various electronic components on the drive circuit board 700, which are cooled by the compressed air AR, are not affected by the ink mist. The risk of dust and other particles adhering to the surface is reduced. This further improves the operational stability of the drive circuit board 700 and the accuracy of ink ejection from the print head 30, which operates based on the output signal output by the drive circuit board 700.

[0393] In other words, the modified liquid ejection device 1, because it uses a cloth as the medium P, is particularly effective in the case of a so-called inkjet printer for textile printing, where there is a high risk of dust floating in the printing area. This is because it further improves the stability of the operation of the drive circuit board 700 and further improves the accuracy of ink ejection from the print head 30, which operates based on the output signal output by the drive circuit board 700.

[0394] Furthermore, in the above-described embodiment, the temperature detection circuit 56, which detects the ambient temperature of the drive circuit module 50, generates a temperature information signal Tt containing temperature information corresponding to the ambient temperature, and outputs it to the head control circuit 12, was described as being provided on the rigid wiring member 750. However, the temperature detection circuit 56 may be provided on the rigid wiring member 730 in an area separate from the drive signal output circuits 52a-3, 52a-4, 52b-3, and 52b-4.

[0395] Figure 33 shows an example of component arrangement in the modified drive circuit board 700 in an unfolded state. As shown in Figure 33, in the modified drive circuit board 700, the temperature detection circuit 56 is located in a region away from the drive signal output circuits 52a-3, 52a-4, 52b-3, and 52b-4. Specifically, the temperature detection circuit 56 is provided along side 731 of the rigid wiring member 730, and the drive signal output circuits 52a-3, 52a-4, 52b-3, and 52b-4 are provided in a region along side 732 of the rigid wiring member 730, which is opposite side 731. In other words, in the rigid wiring member 730, the temperature detection circuit 56 and the drive signal output circuits 52a-3, 52a-4, 52b-3, and 52b-4 are arranged such that the shortest distance between the temperature detection circuit 56 and edge 731 is smaller than the shortest distance between the temperature detection circuit 56 and edge 732, and the shortest distance between the transistors M1 and M2 of each of the drive signal output circuits 52a-3, 52a-4, 52b-3, and 52b-4 and edge 732 is smaller than the shortest distance between the transistors M1 and M2 of each of the drive signal output circuits 52a-3, 52a-4, 52b-3, and 52b-4 and edge 731.

[0396] Even when the temperature detection circuit 56 is arranged in this configuration, because the temperature detection circuit 56 and the drive signal output circuits 52a-3, 52a-4, 52b-3, and 52b-4 are located far apart, the contribution of heat generated by the drive signal output circuits 52a-3, 52a-4, 52b-3, and 52b-4 to the temperature detection circuit 56 is reduced, and the same effects as those of the embodiment described above can be achieved.

[0397] Although embodiments and modified examples have been described above, the present invention is not limited to these embodiments and can be implemented in various forms without departing from its spirit. For example, the above embodiments can be combined as appropriate.

[0398] The present invention includes configurations that are substantially identical to those described in the embodiments (for example, configurations with the same function, method, and result, or configurations with the same purpose and effect). Furthermore, the present invention includes configurations in which non-essential parts of the configurations described in the embodiments are replaced. Furthermore, the present invention includes configurations that produce the same effects or achieve the same purpose as those described in the embodiments. Furthermore, the present invention includes configurations that add known technology to the configurations described in the embodiments.

[0399] The following conclusions can be drawn from the embodiments described above.

[0400] One embodiment of a liquid dispensing device is: A print head that ejects liquid, A circuit board unit electrically connected to the print head, Equipped with, The aforementioned print head is A first discharge unit includes a first piezoelectric element that is displaced in response to a first drive signal, and discharges liquid due to the displacement of the first piezoelectric element, A first connector electrically connected to the aforementioned circuit board unit, It has, The aforementioned circuit board unit is A second connector that, when mated with the first connector, electrically connects to the print head, A wiring board on which multiple circuit components, including the second connector, are provided, It has, The wiring board is a rigid-flexible substrate comprising a plurality of rigid members on which the plurality of circuit components are provided, and a flexible member that is more flexible than the plurality of rigid members, The flexible member includes a first surface, a second surface opposite to the first surface, and a first region, a second region, a third region, a fourth region, and a fifth region. The fourth region is located between the first region and the second region. The fifth region is located between the second region and the third region. The plurality of rigid members include a first rigid member, a second rigid member, a third rigid member, and a fourth rigid member. The first rigid member includes a first surface, and is laminated in the first region on the first surface such that the first surface extends along the first surface. The second rigid member includes a second surface, and is laminated to the first surface in the second region such that the second surface extends along the first surface. The third rigid member includes a third surface, and is laminated on the first surface of the third region such that the third surface extends along the first surface. The fourth rigid member includes a fourth surface, and is laminated on the second surface of the third region such that the fourth surface extends along the second surface. The first rigid member and the second rigid member are positioned such that the first surface and the second surface face each other when the flexible member bends in the fourth region. The third rigid member is positioned such that, as the flexible member bends in the fifth region, the normal direction of the third surface intersects with both the normal direction of the first surface and the normal direction of the second surface. The second connector is provided on the fourth rigid member, When viewed along the direction from the third rigid member toward the fourth rigid member, the sizes of the third rigid member and the fourth rigid member are smaller than the size of the print head when viewed along the direction from the first connector toward the first ejection section.

[0401] This liquid ejection device allows the wiring board of the substrate unit to be roughly box-shaped, thereby increasing the effective area of ​​the wiring board on which circuit components are mounted. This enables multiple circuit components to be placed in appropriate positions on the wiring board. As a result, the influence of noise on the circuit composed of these multiple circuit components is reduced, and the accuracy of the signal output by the substrate unit is improved. Furthermore, by making the size of the fourth rigid member on which the second connector for electrically connecting the substrate unit and the print head is provided smaller than the size of the print head, a dense arrangement of substrate units can be achieved. In other words, this liquid ejection device enables high accuracy of the signal output by the substrate units when they are densely arranged. As a result, the ejection accuracy of the ink ejected from the print head is improved, and a high-definition image can be formed on the medium.

[0402] In one embodiment of the above-described liquid dispensing device, The substrate unit has a first drive circuit that outputs the first drive signal, The first drive circuit may be provided on at least one of the first rigid member and the second rigid member.

[0403] In this liquid ejection device, a first drive circuit that outputs a first drive signal is provided on a wiring board on which a second connector that mates with the first connector of the print head is located. This improves the waveform accuracy of the first drive signal input to the print head, and as a result, improves the ejection accuracy of the ink ejected from the first ejection unit.

[0404] In one embodiment of the above-described liquid dispensing device, The print head includes a second piezoelectric element that is displaced in response to a second drive signal, and has a second discharge section that discharges liquid due to the displacement of the second piezoelectric element. The substrate unit has a second drive circuit that outputs the second drive signal, The first drive circuit is provided on one of the first rigid member and the second rigid member, The second drive circuit may be provided on the other of the first rigid member and the second rigid member.

[0405] This liquid ejection device allows for more precise ink ejection control by providing a second drive circuit that outputs a second drive signal on a wiring board equipped with a second connector that mates with the first connector of the print head. This enables the formation of higher-resolution images on the medium. Furthermore, by providing the first and second drive circuits on different rigid members, the risk of heat generated by the first drive circuit and the second drive circuit interfering with each other is reduced, improving the operational stability of the board unit.

[0406] In one embodiment of the above-described liquid dispensing device, The substrate unit has a first fixing member and a second fixing member, The first fixing member is provided on the first rigid member, The second fixing member is provided on the third rigid member, The first rigid member may be fixed to the third rigid member by fitting the first and second fixing members together.

[0407] This liquid dispensing device allows the shape of the wiring board of the substrate unit to be maintained without the need for a dedicated frame, enabling further miniaturization of the substrate unit and the liquid dispensing device equipped with the substrate unit.

[0408] In one embodiment of the above-described liquid dispensing device, The first rigid member and the third rigid member may be electrically connected via the first fixing member and the second fixing member.

[0409] This liquid dispensing device allows the signal generated by the first rigid member to be propagated to the third and fourth rigid members via the first and second fixed members. This shortens the propagation path of the signal generated by the first rigid member and improves the accuracy of the signal.

[0410] In one embodiment of the above-described liquid dispensing device, The plurality of circuit components include an FPGA that outputs a print head control signal to control the operation of the print head. The FPGA is provided on the first rigid member, The print head control signal may propagate through the first and second fixing members and be input to the print head.

[0411] According to this liquid dispensing device, The print head control signal generated by the first rigid member can be propagated to the third and fourth rigid members via the first and second fixed members. This shortens the propagation path of the print head control signal and improves its accuracy. As a result, the operational accuracy of the print head is improved, and the ejection accuracy of the ink ejected from the print head is improved.

[0412] In one embodiment of the above-described liquid dispensing device, When the wiring board is electrically connected to the print head by the first connector and the second connector, the wiring board may be located inside the print head when viewed along the direction from the wiring board toward the print head.

[0413] This liquid dispensing device allows for a more compact arrangement of substrate units, enabling further miniaturization of both the substrate units and the liquid dispensing device equipped with them.

[0414] In one embodiment of the above-described liquid dispensing device, The plurality of rigid members include a fifth rigid member and a sixth rigid member, The fifth rigid member includes a fifth surface, and is laminated on the first region of the second surface such that the fifth surface extends along the second surface. The sixth rigid member includes a sixth surface, and is laminated on the second region of the second surface such that the sixth surface extends along the second surface. The size of the third rigid member when viewed along the direction from the third rigid member toward the fourth rigid member may be smaller than the size of the first rigid member when viewed along the direction from the first rigid member toward the fifth rigid member, and also smaller than the size of the second rigid member when viewed along the direction from the second rigid member toward the sixth rigid member.

[0415] This liquid dispensing device allows for an even larger effective area on the wiring board where circuit components are mounted, enabling multiple circuit components to be positioned more appropriately on the wiring board. As a result, the impact of noise on the circuit composed of these multiple circuit components is further reduced, and the accuracy of the signal output by the board unit is further improved. [Explanation of Symbols]

[0416] 1…Liquid ejection device, 2…Control unit, 3…Head unit, 4…Transport motor, 5…Transport roller, 6…Carriage motor, 7…Carriage guide shaft, 8…Carriage, 9…Liquid container, 10…Ejection control module, 12…Head control circuit, 14…Cooling fan drive circuit, 16…Main control circuit, 18…Power supply voltage output circuit, 20…Liquid ejection module, 21,22…FFC cable, 30…Print head, 31…Restore circuit, 32…Ejection module, 50…Drive circuit module, 51…Ejection control circuit, 52…Drive signal output circuit, 53 ...capacitor, 54...anomaly detection circuit, 55...anomaly notification circuit, 56...temperature detection circuit, 58...voltage conversion circuit, 59...cooling fan, 60...piezoelectric element, 72...guide rail, 81...carriage body, 82...carriage cover, 83...housing case, 85...mounting part, 86...fixing part, 87...carriage support part, 100...control circuit board, 110...integrated circuit, 150...intermediate board, 151,152...face, 153-156...edge, 158,159...through hole, 160...opening plate, 161-164...opening, 170...heat sink, 172...opening, 175...thermal conductive member ,180…heat sink, 185…thermal conductive material, 200…drive signal selection circuit, 210…selection control circuit, 212…register, 214…latch circuit, 216…decoder, 230…selection circuit, 232a,232b…inverter, 234a,234b…transfer gate, 310…head holder, 315,316…flange, 318…housing section, 320…reinforcement plate, 325…opening, 330…fixing plate, 335…opening, 340…flow channel material, 350…head cover, 360…head board, 370…head relay board, 372,374,37 6…FPC, 380…Head relay board, 382,384,386…FPC, 500…Integrated circuit, 510…Modulation circuit, 512,513…Adder, 514…Comparator, 515…Inverter, 516…Integrating attenuator, 517…Attenuator, 520…Gate drive circuit, 521,522…Gate driver, 530…Reference voltage signal output circuit, 550…Amplifier circuit, 560…Demodulation circuit, 570,572…Feedback circuit, 590…Reference power supply circuit, 600…Ejector, 601…Piezoelectric element, 611,612…Electrode, 621…Diaphragm, 631…Cavity 632...Nozzle plate, 641...Reservoir, 651...Nozzle, 661...Supply port, 700...Drive circuit board, 701-707...Area, 710...Rigid wiring member, 711-714...Edge, 721,722...Rigid member, 723,724...Face, 730...Rigid wiring member, 731-734...Edge, 741,742...Rigid member, 743,744...Face, 750...Rigid wiring member, 751-754...Edge, 761,762...Rigid member, 763,764...Face, 770...Rigid wiring member, 771-774...Edge, 781,782...Rigid Thread components, 783, 784... surfaces, 790... flexible wiring components, 791, 792... surfaces, AR... compressed air, C1-C5, C7, C53... capacitors, CN1, CN1a, CN1b, CN2, CN2a, CN2b, CN3, CN3a, CN3b... connectors, CP... compressor, D1... diode, L1... inductor, M1, M2... transistors, P... medium, R1-R6... resistors, TB... tubes, wb1-wb8, wca1-wca4, wcb1-wcb4, wd1-wd3, wg, wh1-wh7, wm1-wm3... wiring

Claims

1. A print head that ejects liquid, A circuit board unit electrically connected to the print head, Equipped with, The aforementioned print head is A first discharge unit includes a first piezoelectric element that is displaced in response to a first drive signal, and discharges liquid by the displacement of the first piezoelectric element, A first connector electrically connected to the aforementioned circuit board unit, It has, The aforementioned circuit board unit is A second connector that, when mated with the first connector, electrically connects to the print head, A wiring board on which multiple circuit components, including the second connector, are provided, It has, The wiring board is a rigid-flexible substrate comprising a plurality of rigid members on which the plurality of circuit components are provided, and a flexible member that is more flexible than the plurality of rigid members, The flexible member includes a first surface, a second surface opposite to the first surface, and a first region, a second region, a third region, a fourth region, and a fifth region. The fourth region is located between the first region and the second region. The fifth region is located between the second region and the third region. The plurality of rigid members include a first rigid member, a second rigid member, a third rigid member, and a fourth rigid member. The first rigid member includes a first surface, and is laminated on the first surface of the first region such that the first surface extends along the first surface. The second rigid member includes a second surface, and is laminated on the second region of the first surface such that the second surface extends along the first surface. The third rigid member includes a third surface, and the third region is laminated on the first surface such that the third surface extends along the first surface. The fourth rigid member includes a fourth surface, and is laminated to the third region of the second surface such that the fourth surface extends along the second surface. The first rigid member and the second rigid member are positioned such that the first surface and the second surface face each other when the flexible member bends in the fourth region. The third rigid member is positioned such that, as the flexible member bends in the fifth region, the normal direction of the third surface intersects with both the normal direction of the first surface and the normal direction of the second surface. The second connector is provided on the fourth rigid member, The sizes of the third rigid member and the fourth rigid member, when viewed along the direction from the third rigid member toward the fourth rigid member, are smaller than the size of the print head, when viewed along the direction from the first connector toward the first ejection section. A liquid dispensing device characterized by the following features.

2. The substrate unit has a first drive circuit that outputs the first drive signal, The first drive circuit is provided on at least one of the first rigid member and the second rigid member. The liquid dispensing device according to feature 1.

3. The print head includes a second piezoelectric element that is displaced in response to a second drive signal, and has a second discharge unit that discharges liquid due to the displacement of the second piezoelectric element. The substrate unit has a second drive circuit that outputs the second drive signal, The first drive circuit is provided on one of the first rigid member and the second rigid member, The second drive circuit is provided on the other side of the first rigid member and the second rigid member. The liquid dispensing device according to feature 2.

4. The substrate unit has a first fixing member and a second fixing member, The first fixing member is provided on the first rigid member, The second fixing member is provided on the third rigid member, The first rigid member is fixed to the third rigid member by fitting the first and second fixing members together. The liquid dispensing device according to feature 1.

5. The first rigid member and the third rigid member are electrically connected via the first fixing member and the second fixing member. The liquid dispensing device according to feature 4.

6. The plurality of circuit components include an FPGA that outputs a print head control signal to control the operation of the print head, The FPGA is provided on the first rigid member, The print head control signal propagates through the first and second fixing members and is input to the print head. The liquid dispensing device according to feature 5.

7. With the wiring board electrically connected to the print head by the first and second connectors, when viewed along the direction from the wiring board toward the print head, the wiring board is located inside the print head. The liquid dispensing device according to feature 1.

8. The plurality of rigid members include a fifth rigid member and a sixth rigid member, The fifth rigid member includes a fifth surface, and is laminated on the first region of the second surface such that the fifth surface extends along the second surface. The sixth rigid member includes a sixth surface, and is laminated on the second surface of the second region such that the sixth surface extends along the second surface. The size of the third rigid member when viewed along the direction from the third rigid member toward the fourth rigid member is smaller than the size of the first rigid member when viewed along the direction from the first rigid member toward the fifth rigid member, and also smaller than the size of the second rigid member when viewed along the direction from the second rigid member toward the sixth rigid member. A liquid dispensing device according to any one of claims 1 to 7.

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