Liquid ejection head and liquid ejection apparatus

Abstract

The invention provides a liquid ejection head and a liquid ejection apparatus. The liquid ejection head can detect the pressure of an absorption chamber in the vicinity of a pressure chamber. The liquid ejection head includes: a nozzle substrate provided with a nozzle that ejects a liquid; a pressure chamber substrate having a pressure chamber that applies a pressure for discharging the liquid from the nozzle to the liquid, and an absorption chamber that is adjacent to the pressure chamber in a second direction and that absorbs vibration of the liquid generated when the pressure is applied to the liquid in the pressure chamber; a first vibration plate that is provided so as to correspond to the pressure chamber and vibrates in order to apply pressure to the liquid; a second vibration plate that is provided so as to correspond to the absorption chamber and vibrates in order to absorb the pressure of the liquid; a second wiring portion provided at a position corresponding to the absorption chamber; and a pressure acquisition unit that acquires the pressure of the absorption chamber on the basis of the resistance value of the second wiring unit.

Description

Technical Field

[0001] The present invention relates to a liquid ejection head and a liquid ejection device. Background Art

[0002] A liquid ejection device having a plurality of heads for ejecting liquid such as ink onto a medium such as printing paper has been proposed. In recent years, inkjet printers have attracted attention not only for printing purposes but also as devices capable of applying liquefiable materials at any location. An inkjet printer has a liquid ejection head for ejecting liquid. As a liquid ejection head, a head is known that uses a piezoelectric element to vibrate a vibration plate constituting a wall surface of a pressure chamber, thereby ejecting liquid filled in the pressure chamber from a nozzle.

[0003] The liquid ejection head described in Patent Document 1 has a pressure chamber and a liquid storage chamber provided at a position different from the pressure chamber. Since the liquid storage chamber can effectively absorb the pressure fluctuation caused by the liquid, the stability of the liquid ejection from the nozzle is improved.

[0004] However, in the liquid ejection head described in Patent Document 1, the pressure chamber and the liquid storage chamber are provided at positions separated from each other via a large number of components. Therefore, the absorption efficiency of liquid vibration in the pressure chamber is low. It is believed that by providing the liquid storage chamber at a position adjacent to the pressure chamber, the absorption efficiency of liquid vibration can be improved.

[0005] However, in a liquid ejection head, the behavior of the liquid changes greatly depending on the pressure of the pressure chamber. Therefore, obtaining the pressure has always been a problem. The inventors have found a structure that can detect the pressure near the pressure chamber by using the liquid storage chamber in the above-mentioned method of providing a liquid storage chamber at a position adjacent to the pressure chamber with a simple structure.

[0006] Patent Document 1: Japanese Patent Application Publication No. 2018-153926 Summary of the invention

[0007] A preferred embodiment of the present invention involves a liquid ejection head comprising: a nozzle substrate, which is provided with a nozzle for ejecting liquid; a pressure chamber substrate, which has a pressure chamber and an absorption chamber, the pressure chamber applies pressure to the liquid for ejecting the liquid from the nozzle, and the absorption chamber is adjacent to the second direction of the pressure chamber and absorbs the vibration of the liquid generated when pressure is applied to the liquid in the pressure chamber; a first vibration plate, which is arranged corresponding to the pressure chamber and vibrates to apply pressure to the liquid; a second vibration plate, which is arranged corresponding to the absorption chamber and vibrates to absorb the pressure of the liquid; a second wiring portion, which is arranged at a position corresponding to the absorption chamber; and a pressure acquisition portion, which acquires the pressure of the absorption chamber based on the resistance value of the second wiring portion. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 This is a schematic diagram illustrating the structure of the liquid ejecting device according to the first embodiment.

[0009] Figure 2 for Figure 1 Block diagram of a liquid ejection device.

[0010] Figure 3 for Figure 1 A cross-sectional view of a portion of a liquid ejection head is shown.

[0011] Figure 4 To express Figure 3 Figure 2. A diagram of a portion of the pressure chamber substrate.

[0012] Figure 5 for Figure 3 A cross-sectional view of a first piezoelectric element, a first wiring portion, and a second wiring portion.

[0013] Figure 6 To express Figure 3 FIG. 1 is a diagram of a portion of a first piezoelectric body.

[0014] Figure 7 To express Figure 2 A diagram of a second electrode, a first wiring portion, and a second wiring portion.

[0015] Figure 8 To express Figure 2 FIG. 1 is a diagram of a bridge circuit included in a pressure detection unit.

[0016] Fig. 9 To express Figure 2 FIG. 1 is a diagram of a portion of a temperature detection unit.

[0017] Fig.10 It is a diagram showing a first wiring portion according to the second embodiment.

[0018] Fig.11 It is a diagram showing a first wiring portion according to the third embodiment.

[0019] Fig.12 This is a block diagram of a liquid ejection device according to a modified example.

[0020] Fig.13 This is a cross-sectional view of a portion of a liquid ejection head according to a modified example. DETAILED DESCRIPTION

[0021] Hereinafter, the preferred embodiments of the present invention will be described with reference to the accompanying drawings. In addition, in each of the drawings, the size and scale of each part are appropriately different from the actual situation, and there are also parts schematically shown for easy understanding. In addition, in the following description, as long as there is no record indicating the meaning of particularly limiting the present invention, the scope of the present invention is not limited to these modes. In addition, "element β on element γ" is not limited to a structure in which element γ is in direct contact with element β, but also includes a structure in which element γ is not in direct contact with element β. "Element γ is the same as element β" only requires that element γ is substantially the same as element β, and also includes manufacturing errors, etc.

[0022] 1. First Implementation

[0023] 1-1. Overall Structure of Liquid Dispensing Device 100

[0024] Figure 1 This is a schematic diagram illustrating the structure of the liquid ejection device 100 involved in the first embodiment. In the following, for the convenience of explanation, the X-axis, Y-axis and Z-axis that are orthogonal to each other are appropriately used for explanation. In addition, a direction along the X-axis is marked as the X1 direction, and the direction opposite to the X1 direction is marked as the X2 direction. Similarly, a direction along the Y-axis is marked as the Y1 direction, and the direction opposite to the Y1 direction is marked as the Y2 direction. A direction along the Z-axis is marked as the Z1 direction, and the direction opposite to the Z1 direction is marked as the Z2 direction.

[0025] Figure 1 The liquid ejection device 100 is an inkjet printing device that ejects ink, which is an example of liquid, onto a medium 90. The medium 90 is typically a printing paper, but the medium 90 can be used as a printing object of any material such as a resin film or cloth. Figure 1 As illustrated, a liquid container 9 for storing ink is provided in the liquid ejection device 100. For example, an ink cartridge that is detachable from the liquid ejection device 100, a bag-shaped ink pack formed of a flexible film, or an ink tank that can be replenished with ink can be used as the liquid container 9.

[0026] The liquid ejection device 100 includes a control unit 20, a medium conveying mechanism 22, a moving mechanism 24, and a liquid ejection head 1. The control unit 20 includes, for example, one or more processing circuits such as a CPU (Central Processing Unit) or an FPGA (Field Programmable Gate Array) and one or more storage circuits such as a semiconductor memory, and comprehensively controls various elements of the liquid ejection device 100.

[0027] The medium conveying mechanism 22 conveys the medium 90 in the direction along the Y axis based on the control implemented by the control unit 20. In addition, the moving mechanism 24 reciprocates the liquid ejecting head 1 along the X axis based on the control implemented by the control unit 20. The moving mechanism 24 includes a substantially box-shaped conveying body 242 for accommodating the liquid ejecting head 1, and a conveying belt 244 to which the conveying body 242 is fixed. In addition, a structure in which a plurality of liquid ejecting heads 1 are mounted on the conveying body 242, or a structure in which the liquid container 9 is mounted on the conveying body 242 together with the liquid ejecting head 1, may be adopted.

[0028] The liquid ejection head 1 ejects ink supplied from the liquid container 9 from a plurality of nozzles toward the medium 90 based on control by the control unit 20. Each liquid ejection head 1 ejects ink toward the medium 90 in parallel with the transport of the medium 90 by the medium transport mechanism 22 and the repeated reciprocation of the transport body 242, thereby forming an image on the surface of the medium 90.

[0029] Figure 2 for Figure 1 A block diagram of a liquid ejection device 100 is shown. Figure 2 As shown, the liquid ejection device 100 includes a control unit 20, a medium conveying mechanism 22, a moving mechanism 24, and a liquid ejection head 1. The control unit 20 includes a control unit 21, a storage unit 23, and a drive signal generating circuit 25. The liquid ejection head 1 includes a drive circuit 40, a plurality of first piezoelectric elements 3, a temperature acquisition unit 41, a pressure acquisition unit 42, a temperature detection unit 5, and a pressure detection unit 6.

[0030] The control unit 21 includes one or more processing circuits such as a CPU or an FPGA. The control unit 21 generates signals for controlling the operation of each part of the liquid ejection device 100. The control unit 21 controls the ink ejection operation performed by the liquid ejection head 1.

[0031] The control unit 21 generates a printing signal SI, a waveform designation signal dCom, and a timing signal PTS. The printing signal SI is a digital signal for designating the type of action of the liquid ejection head 1. The printing signal SI designates whether to supply the drive signal Com to the first piezoelectric element 3. The waveform designation signal dCom is a digital signal that specifies the waveform of the drive signal Com. The drive signal Com is an analog signal for driving the first piezoelectric element 3. The timing signal PTS is a signal that specifies the timing of generating the drive signal Com.

[0032] The storage unit 23 includes one or more storage circuits such as semiconductor memories. The storage unit 23 stores the print data Img supplied from the host computer. The storage unit 23 stores the control program of the liquid ejecting device 100.

[0033] The drive signal generation circuit 25 includes a DA conversion circuit. The drive signal generation circuit 25 generates a drive signal Com having a waveform specified by the waveform designation signal dCom. The drive signal generation circuit 25 outputs the drive signal Com every time it receives the timing signal PTS.

[0034] The drive circuit 40 switches whether to supply the drive signal Com to each first piezoelectric element 3 based on the print signal SI. The drive circuit 40 selects the first piezoelectric element 3 to which the drive signal Com is supplied based on the print signal SI, the latch signal LAT, and the exchange signal CH supplied from the control unit 20. The latch signal LAT specifies the latch timing of the print data Img. The exchange signal CH specifies the selection timing of the drive pulse included in the drive signal Com.

[0035] The temperature acquisition unit 41 acquires the temperature of the absorption chamber S2 of the liquid ejection head 1 described later based on the resistance value of the first wiring unit 50 of the temperature detection unit 5. The pressure acquisition unit 42 acquires the pressure of the absorption chamber S2 based on the resistance value of the second wiring unit 60 of the pressure detection unit 6.

[0036] 1-2. Liquid ejection head 1

[0037] Figure 3 for Figure 1The cross-sectional view of a portion of the liquid ejection head 1 shown is a cross-sectional view parallel to the XZ plane. The Z axis is an axis along the ejection direction of the ink achieved by the liquid ejection head 1. The direction along the Z axis is set as the "up and down direction". The Z2 direction is an example of "one side in the up and down direction", and the Z1 direction is an example of "the other side in the up and down direction". In addition, observation from the direction along the Z axis intersecting the Y2 direction and the X2 direction is set as "planar observation". The Y1 direction or the Y2 direction is an example of the "first direction". The X1 direction or the X2 direction is an example of the "second direction".

[0038] Figure 3 The liquid ejection head 1 is a structure that is substantially plane-symmetrical with respect to an imaginary plane a along the Y-Z plane. Figure 3 The structure on the right side of the figure is described, and the structure close to the imaginary plane a is omitted appropriately. Figure 3 Description of the structure on the left.

[0039] The liquid ejection head 1 includes a nozzle substrate 11, a pressure chamber substrate 12, a vibration plate 13, a sealing substrate 14, a wiring substrate 49, a first piezoelectric element 3, a pressure detection unit 6, and a temperature detection unit 5. The first piezoelectric element 3 includes a first piezoelectric body 31, a first electrode 32, and a second electrode 33. The pressure detection unit 6 includes a second wiring unit 60. The temperature detection unit 5 includes a first wiring unit 50. In addition, although not shown in detail, the nozzle substrate 11, the pressure chamber substrate 12, the vibration plate 13, and the sealing substrate 14 are in the shape of a long and narrow plate along the Y axis.

[0040] The nozzle substrate 11 is a plate-shaped member provided with a plurality of nozzles N for ejecting ink as an example of liquid. The plurality of nozzles N are circular through holes for ejecting ink. The plurality of nozzles N are arranged in a straight line along the Y axis. The nozzle substrate 11 is manufactured by processing a semiconductor substrate such as a single crystal silicon substrate, for example.

[0041] The pressure chamber substrate 12 is a flow channel structure having flow channels formed therein for supplying ink to the plurality of nozzles N. The pressure chamber substrate 12 is a laminate of a first substrate 121 and a second substrate 122. The first substrate 121 and the second substrate 122 are manufactured by processing semiconductor substrates such as single crystal silicon substrates, for example. In addition, each of the first substrate 121 and the second substrate 122 may be formed integrally. In addition, the pressure chamber substrate 12 may also include components other than the first substrate 121 and the second substrate 122.

[0042] The flow path of the ink is formed on the pressure chamber substrate 12. Specifically, a plurality of pressure chambers S1, an absorption chamber S2, a plurality of first communication flow paths R1, and a second communication flow path R2 are formed on the pressure chamber substrate 12. The first substrate 121 and the second substrate 122 respectively have recesses or through holes, and the plurality of pressure chambers S1, the absorption chamber S2, a plurality of first communication flow paths R1, and a second communication flow path R2 are formed through these recesses or through holes.

[0043] Figure 4 To express Figure 3 FIG. 1 is a diagram of a portion of a pressure chamber substrate 12. Figure 4 As shown, each pressure chamber S1 is a narrow and long shape extending in the X2 direction. The plurality of pressure chambers S1 are separated from each other and arranged in the Y2 direction. Therefore, the direction in which the plurality of pressure chambers S1 are arranged is the Y2 direction as the "first direction". In addition, the plurality of pressure chambers S1 are provided in a one-to-one manner with the plurality of nozzles N. Each pressure chamber S1 is a space for applying pressure to the ink for ejecting the ink from the nozzle N.

[0044] The plurality of first communication channels R1 are separated from each other and arranged in the Y2 direction. The plurality of first communication channels R1 are arranged in a one-to-one manner with the plurality of pressure chambers S1. Each first communication channel R1 connects the corresponding pressure chamber S1 with the nozzle N. Each first communication channel R1 overlaps with the corresponding pressure chamber S1 and the nozzle N when viewed in a plan view.

[0045] The absorption chamber S2 is arranged on the upstream side relative to the plurality of pressure chambers S1. The direction in which the pressure chambers S1 and the absorption chamber S2 are arranged is the X2 direction, which is the "second direction". The absorption chamber S2 is a long and narrow shape extending in the Y2 direction. The volume of the absorption chamber S2 is very large compared to the volume of each pressure chamber S1. The absorption chamber S2 is commonly provided for the plurality of pressure chambers S1, and is connected to the plurality of pressure chambers S1 via a plurality of connecting flow channels S0. The absorption chamber S2 is adjacent to the pressure chamber S1, and absorbs the vibration of the ink that occurs when pressure is applied to the ink in the pressure chamber S1. By providing the absorption chamber S2, the ink ejection performance can be stabilized. In addition, by making the absorption chamber S2 adjacent to the pressure chamber S1, the absorption efficiency of the ink vibration can be improved compared to the case where the absorption chamber S2 is separated from the pressure chamber S1. Therefore, the stability of the ink ejection performance can be improved.

[0046] The second communication flow passage R2 is provided at the upstream side of the absorption chamber S2 and is connected to the absorption chamber S2. The second communication flow passage R2 is in a long and narrow shape extending in the Y2 direction.

[0047] like Figure 3As shown, a vibration plate 13 is arranged on the surface of the pressure chamber substrate 12 in the Z2 direction. The thickness of the vibration plate 13 is very thin compared with the thickness of the first substrate 121 and the second substrate 122 of the pressure chamber substrate 12. The thickness is the length in the Z1 direction. The vibration plate 13 can be elastically deformed. The vibration plate 13 includes a plurality of first vibration plates 131 and a second vibration plate 132. The plurality of first vibration plates 131 and the second vibration plate 132 are formed by one component.

[0048] The plurality of first vibration plates 131 are provided in a one-to-one manner with the plurality of pressure chambers S1. Each first vibration plate 131 is a portion of the vibration plate 13 that overlaps with the plurality of pressure chambers S1 when viewed in a plan view. Each first vibration plate 131 forms a portion of the pressure chamber S1. Each first vibration plate 131 vibrates by applying a voltage to the first piezoelectric body 31 of the first piezoelectric element 3, and applies pressure to the pressure chamber S1. Therefore, the first vibration plate 131 is provided corresponding to the pressure chamber S1, and vibrates to apply pressure to the ink.

[0049] The second vibration plate 132 is a portion of the vibration plate 13 that overlaps with the absorption chamber S2 when viewed from a plane. The second vibration plate 132 forms a portion of the absorption chamber S2. The second vibration plate 132 is provided corresponding to the absorption chamber S2, and vibrates to absorb the pressure of the ink. Moreover, the second vibration plate 132 vibrates by applying pressure from the absorption chamber S2, and applies pressure to the second wiring portion 60 disposed on the second vibration plate 132.

[0050] In addition, the plurality of first vibration plates 131 and the second vibration plates 132 are not separated but formed by one continuous member. Therefore, it is easy to make each first vibration plate 131 adjacent to the second vibration plate 132. Therefore, it is easy to make the plurality of pressure chambers S1 adjacent to the absorption chamber S2. Since the plurality of pressure chambers S1 can be adjacent to the absorption chamber S2, the absorption efficiency of the vibration of the ink can be improved.

[0051] The vibration plate 13 is manufactured by processing a semiconductor substrate such as a single crystal silicon substrate, for example. Alternatively, the vibration plate 13 may be formed by a portion of the pressure chamber substrate 12. For example, the vibration plate 13 may be formed by thinning a portion of the second substrate 122.

[0052] A sealing substrate 14 is disposed on the surface in the Z2 direction of the vibration plate 13. The sealing substrate 14 is a structure that protects a plurality of first piezoelectric elements 3 and the like described later and reinforces the mechanical strength of the pressure chamber substrate 12.

[0053] The third communication channel R3, the first space H1, and the wiring space H0 are formed on the sealing substrate 14. The sealing substrate 14 has a recess or a through hole, and each channel or space is formed by these recesses or through holes. The third communication channel R3 and the wiring space H0 are holes that penetrate the sealing substrate 14. The first space H1 is a space surrounded by the recess formed on the sealing substrate 14.

[0054] The third communication flow channel R3 overlaps with the second communication flow channel R2 when viewed in a plan view, and is connected to the second communication flow channel R2. A common ink chamber R0 is formed by the third communication flow channel R3 and the second communication flow channel R2. The common ink chamber R0 functions as a liquid reservoir. In addition, a filter 141 for removing bubbles and foreign matter mixed in the ink is provided at a portion overlapping with the common ink chamber R0 when viewed in a plan view. The filter 141 may also be omitted.

[0055] Although not shown in the figure, the first space H1, the third communication flow path R3, and the wiring space H0 are each in a long and narrow shape extending in the Y2 direction. The wiring space H0, the first space H1, and the third communication flow path R3 are arranged in this order in the X2 direction.

[0056] like Figure 3 As shown, in the first space H1, a plurality of first piezoelectric elements 3, a first wiring portion 50, and a second wiring portion 60 are arranged. A wiring substrate 49 is arranged in the wiring space H0. The wiring substrate 49 and the pressure chamber substrate 12 are bonded together. The wiring substrate 49 is a mounting component formed with a plurality of wirings for electrically connecting the control unit 20 and the liquid ejection head 1. As the wiring substrate 49, for example, TCP (Tape Carrier Package) or FPC (Flexible Printed Circuit) can be used.

[0057] Figure 5 for Figure 3 FIG1 is a cross-sectional view of a portion of the first piezoelectric element 3, the first wiring portion 50, and the second wiring portion 60. The first piezoelectric element 3, the first wiring portion 50, and the second wiring portion 60 are arranged on the vibration plate 13. The first piezoelectric element 3 is located on the pressure chamber S1 in a manner mainly arranged on the first vibration plate 131. The second wiring portion 60 is located on the absorption chamber S2 in a manner arranged on the second vibration plate 132. The first wiring portion 50 does not overlap with the plurality of pressure chambers S1 and the absorption chambers S2 when viewed in a plan view.

[0058] The first piezoelectric element 3 is arranged on the surface of the first vibration plate 131 on the opposite side to the pressure chamber S1. The first piezoelectric element 3 is a long and narrow shape extending in the X2 direction. The first piezoelectric element 3 is provided corresponding to the pressure chamber S1 and is provided for each pressure chamber S1. The plurality of first piezoelectric elements 3 are separated from each other and arranged in the Y2 direction.

[0059] The first piezoelectric element 3 is an energy generating element that generates energy for ejecting ink by being applied with a driving signal Com. In addition, the first piezoelectric element 3 is also a driving element that is driven by being applied with a driving signal Com. The first piezoelectric body 31 of the first piezoelectric element 3 contracts when a voltage is applied, so that the first vibration plate 131 is bent, thereby pressurizing the pressure chamber S1.

[0060] The first piezoelectric element 3 schematically includes a second electrode 33, a first piezoelectric body 31, and a first electrode 32. The second electrode 33, the first piezoelectric body 31, and the first electrode 32 are stacked in this order from the first vibration plate 131. Therefore, the first electrode 32 is located in the "upper direction" of the "one side in the up-down direction", that is, the Z2 direction, compared to the first piezoelectric body 31. The second electrode 33 is located in the "lower direction" of the "other side in the up-down direction", that is, the Z1 direction, compared to the first piezoelectric body 31. By providing the first electrode 32 and the second electrode 33, a voltage can be efficiently applied to the first piezoelectric body 31. In addition, the second electrode 33 and the first vibration plate 131 may be in contact with each other, or there may be other components between the second electrode 33 and the first vibration plate 131.

[0061] Figure 6 To express Figure 3 FIG. 3 is a diagram of a portion of the first piezoelectric body 31. Figure 6 In the example of , a plurality of first piezoelectric bodies 31 are connected to each other. Specifically, a plurality of first piezoelectric bodies 31 are separated by forming a plurality of cuts G on a strip-shaped dielectric film 310 extending along the Y2 direction. The first piezoelectric body 31 is formed, for example, using a known piezoelectric material such as lead zirconate titanate (Pb(Zr, Ti)O3).

[0062] In addition, Figure 6 In the example of FIG. 3 , the dielectric film 310 overlaps with the absorption chamber S2 . However, the dielectric film 310 may not overlap with the absorption chamber S2 . In addition, the plurality of first piezoelectric bodies 31 may not be connected to each other but may be formed separately.

[0063] Figure 3The first electrode 32 shown is a common electrode commonly provided for the plurality of first piezoelectric bodies 31. The first electrode 32 is in the shape of a strip extending in the Y2 direction in a continuous manner across the plurality of first piezoelectric elements 3. By providing the first electrode 32 commonly for the plurality of pressure chambers S1, it is easier to achieve miniaturization of the first piezoelectric elements 3 than in the case where they are provided individually. The first electrode 32 is formed of a low-resistance conductive material such as platinum (Pt) or iridium (Ir), similarly to the second electrode 33.

[0064] Figure 7 To express Figure 2 FIG. 3 is a diagram of the second electrode 33, the first wiring section 50 and the second wiring section 60. Figure 7 As shown in FIG. 1 , the second electrode 33 is long and narrow along the X-axis. The plurality of second electrodes 33 are separated from each other and arranged along the Y-axis. The second electrode 33 is a separate electrode formed separately from each other for each first piezoelectric element 3. The second electrode 33 is provided separately with respect to the plurality of pressure chambers S1. By providing the second electrode 33 separately, even when the plurality of first piezoelectric bodies 31 are formed by one dielectric film 310, one dielectric film 310 can be divided into a plurality of first piezoelectric bodies 31. The second electrode 33 is formed by, for example, a conductive material such as platinum or iridium.

[0065] The first piezoelectric element 3 is a piezoelectric element related to the ejection of ink. A reference voltage as a constant voltage is applied to the first electrode 32. The reference voltage can be, for example, a ground voltage or a voltage higher than the ground voltage. A driving signal Com is supplied to the second electrode 33. Therefore, a driving voltage that changes with time is applied to the second electrode 33.

[0066] A voltage corresponding to the difference between the reference voltage applied to the first electrode 32 and the driving voltage supplied to the second electrode 33 is applied to the first piezoelectric body 31. Figure 2 The driving circuit 40 applies a driving voltage that changes the voltage according to time to the first piezoelectric body 31. The first piezoelectric body 31 is deformed by applying a voltage corresponding to the difference between the reference voltage applied to the first electrode 32 and the driving voltage supplied to the second electrode 33 to the first piezoelectric body 31, so that the first piezoelectric element 3 generates energy that flexibly deforms the first vibration plate 131. Therefore, the first piezoelectric element 3 applies pressure to the pressure chamber S1 by the application of this voltage. By utilizing the energy generated by the first piezoelectric element 3 to flexibly deform the first vibration plate 131, the pressure in the pressure chamber S1 changes, and the ink in the pressure chamber S1 is moved from the first vibration plate 131 to the second vibration plate 131. Figure 3 The nozzle N shown is sprayed.

[0067] Figure 3 The second wiring section 60 shown is provided corresponding to the absorption chamber S2. Specifically, the second wiring section 60 is arranged on the surface of the second vibration plate 132 which is opposite to the absorption chamber S2. In addition, the second wiring section 60 is covered by the dielectric film 310. The second wiring section 60 is used to detect the pressure of the absorption chamber S2. The second wiring section 60 is a strain gauge. The second wiring section 60 is formed using metal or semiconductor, etc.

[0068] The pressure of the absorption chamber S2 is detected by using the characteristic that the resistance value of metal or semiconductor changes due to deformation. When an external force is applied to the second wiring part 60 via the second vibration plate 132 according to the pressure of the absorption chamber S2, a stress corresponding to the external force acts on the second wiring part 60. As a result, the second wiring part 60 is deformed, causing the resistance value to change. By using this resistance value, the pressure of the absorption chamber S2 can be detected.

[0069] As described above, in the liquid ejection head 1 of the present embodiment, a pressure chamber S1 and an absorption chamber S2 are provided on the pressure chamber substrate 12, and the pressure chamber S1 is adjacent to the absorption chamber S2. In the manner in which the pressure chamber S1 is adjacent to the absorption chamber S2, a second wiring portion 60 is provided corresponding to the second vibration plate 132. In addition, in the liquid ejection head 1, a pressure acquisition portion 42 for acquiring the pressure of the absorption chamber S2 based on the resistance value of the second wiring portion 60 is provided. For example, the pressure acquisition portion 42 has a detection circuit for acquiring an output voltage obtained based on the resistance value of the second wiring portion 60. The pressure acquisition portion 42 detects the pressure of the absorption chamber S2 based on the correspondence between the resistance value of the second wiring portion 60 and the pressure stored in the storage portion 23.

[0070] As described above, the absorption chamber S2 is a space for absorbing the vibration of the ink generated when the pressure is applied to the ink in the pressure chamber S1. By providing the absorption chamber S2, the ink ejection performance can be stabilized. In the present embodiment, the second wiring portion 60 is provided corresponding to the second vibration plate 132 corresponding to the absorption chamber S2, and the pressure of the absorption chamber S2 can be detected based on the resistance value of the second wiring portion 60. Therefore, the pressure near the pressure chamber S1 can be detected by using the absorption chamber S2. Therefore, it is not necessary to form a space for detecting the pressure near the pressure chamber S1 separately, and the pressure near the pressure chamber S1 can be detected with a simple structure. Since the pressure of the absorption chamber S2 near the pressure chamber S1 can be obtained, the behavior of the ink corresponding to the pressure of the pressure chamber S1 can be detected. Therefore, for example, various adverse conditions such as insufficient supply of ink to multiple pressure chambers S1 and the absorption chamber S2 can be detected. Therefore, since the pressure of the absorption chamber S2 near the pressure chamber S1 can be obtained, it can contribute to the improvement of the quality of the liquid ejection head 1.

[0071] Furthermore, the absorption chamber S2 is not directly related to the discharge of ink like the pressure chamber S1. Therefore, the pressure of the absorption chamber S2 can be detected based on the resistance value of the second wiring portion 60 regardless of the discharge of ink and can be always detected.

[0072] Furthermore, the second wiring section 60 is disposed at a position overlapping with the absorption chamber S2 when viewed in a plan view. Therefore, the resistance value of the second wiring section 60 is easily affected by the pressure change in the absorption chamber S2. By disposing the second wiring section 60 at a position overlapping with the absorption chamber S2, the pressure of the absorption chamber S2 can be detected with high accuracy compared to a case where there is no overlap.

[0073] like Figure 7 As shown, the second wiring portion 60 includes a first folded portion 61 and a first straight portion 62. The first folded portion 61 is a second folded shape that extends in the X2 direction and is sequentially folded back in the Y2 direction. The first straight portion 62 is a straight line extending in the Y2 direction.

[0074] The first folded portion 61 includes a plurality of first portions 611 and a plurality of second portions 612. The plurality of first portions 611 are portions extending in the X2 direction, which are separated from each other and arranged in the Y2 direction. The plurality of second portions 612 are portions extending in the Y2 direction. Each second portion 612 is disposed between two adjacent first portions 611 and connects the two adjacent first portions 611. The plurality of second portions 612 are alternately disposed at the ends of the first portion 611 in the X1 direction and at the ends of the X2 direction. The second portion 612 located closest to the Y1 direction among the plurality of second portions 612 is set as the first, and the plurality of second portions 612 are counted in the Y2 direction. In this case, for example, the odd-numbered second portions 612 among the plurality of second portions 612 are connected to the ends of the first portion 611 in the X1 direction. The even-numbered second portions 612 among the plurality of second portions 612 are connected to the ends of the first portion 611 in the X2 direction.

[0075] Furthermore, the length of one first portion 611 is longer than the length of one second portion 612. As a result, the first portion 611 alternately bends in the X1 direction and the X2 direction, and the second portion 612 gradually shifts in the Y2 direction, so that the entire shape extends in the Y2 direction. This shape is called a "shape that extends in the X2 direction and bends back in sequence."

[0076] The first folded portion 61 of the second wiring portion 60 is configured to have a second folded shape that extends in the Y1 direction and folds back in sequence. Therefore, by making the first folded portion 61 have the second folded shape, it is easier to change the deformation according to the pressure and to show the change in the resistance value, compared with the case where the first folded portion 61 has a folded shape that extends in the X1 direction and folds back in sequence. Therefore, high sensitivity can be achieved.

[0077] The first corrugated portion 61 and the first linear portion 62 are connected to each other. For example, one end of the first corrugated portion 61 and one end of the first linear portion 62 are connected to each other via a wiring (not shown).

[0078] Figure 8 To express Figure 2 FIG. 6 is a diagram of a bridge circuit of the pressure detection unit 6. Figure 8 As shown, the pressure detection unit 6 has a first resistor 63, a second resistor 64, and a third resistor 65 in addition to the first wiring unit 50. The first wiring unit 50, the first resistor 63, the second resistor 64, and the third resistor 65 constitute a Wheatstone bridge circuit. Figure 8One of the other end of the first folded portion 61 of the second wiring portion 60 and the other end of the first straight portion 62 is connected to the first resistor element 63 via the wiring 505. The other end is connected to the third resistor element 65 via the wiring 506. In addition, the first resistor element 63 is connected to the second resistor element 64 via the wiring 507. The second resistor element 64 is connected to the third resistor element 65 via the wiring 508.

[0079] In this bridge circuit, a voltage E is applied to point A and point B, and an output voltage e from point C and point D is detected. When the resistance value of the second wiring portion 60 changes, a voltage difference is generated between point C and point D. This voltage difference, that is, the output voltage e, is obtained, and the deformation of the second wiring portion 60 is obtained. The relationship between the output voltage e, the deformation, and the pressure is pre-stored in the storage unit 23. Therefore, based on the output voltage e obtained based on the resistance value, the pressure of the absorption chamber S2 can be obtained.

[0080] In addition, although Figure 2 Although not shown in the figure, a power supply circuit that supplies voltage E to points A and B is connected to the bridge circuit of the pressure detection unit 6. In addition, a detection circuit that detects the output voltage e based on the resistance value of the second wiring unit 60 is connected to the bridge circuit of the pressure acquisition unit 42. Figure 2 The pressure acquisition unit 42 has the detection circuit.

[0081] As described above, the pressure detection unit 6 can constitute a Wheatstone bridge circuit by including the first resistor 63, the second resistor 64, and the third resistor 65 in addition to the second wiring unit 60. Therefore, the output voltage e obtained based on the resistance value of the second wiring unit 60 can detect the slight pressure in the absorption chamber S2.

[0082] like Figure 5 As shown, the first wiring portion 50 is arranged between the plurality of second electrodes 33 and the second wiring portion 60. The first wiring portion 50 is arranged on the vibration plate 13 and is provided in the same layer as the plurality of second electrodes 33 and the second wiring portion 60. The first wiring portion 50 is covered by a dielectric film 310. The first wiring portion 50 is a resistor used for detecting the temperature of the absorption chamber S2.

[0083] like Figure 7As shown, the first wiring section 50 has a first pleated shape that is folded back in sequence while extending along the Y2 direction. The first wiring section 50 includes a plurality of third portions 51 and a plurality of fourth portions 52. The plurality of third portions 51 are portions extending in the Y2 direction, which are separated from each other and arranged in the X2 direction. In the illustrated example, three third portions 51 are provided. A plurality of fourth portions 52 are portions extending in the X2 direction. Each fourth portion 52 is arranged between two adjacent third portions 51 and connects the two adjacent third portions 51. In the illustrated example, two fourth portions 52 are provided. The fourth portion 52 on one side extends in the X2 direction from the end of the third portion 51 in the Y2 direction located at the center among the three third portions 51. The fourth portion 52 on the other side extends in the X1 direction from the end of the third portion 51 in the Y1 direction located at the center among the three third portions 51.

[0084] Furthermore, the length of one third portion 51 is longer than the length of one fourth portion 52. As a result, the third portion 51 is alternately bent in the Y1 direction and the Y2 direction, and the fourth portion 52 gradually shifts in the X2 direction, so that the entire shape extends in the Y2 direction. This shape is called a "shape that extends in the Y2 direction and folds back in sequence."

[0085] In this way, the first wiring section 50 is configured to have a first folded shape while extending along the Y2 direction and folding back in sequence. Therefore, for example, the first wiring section 50 can be arranged to be thinner and longer in a relatively narrow area such as the area between the pressure chamber S1 and the absorption chamber S2 when viewed in a plan view. Therefore, the first wiring section 50 can be made high in resistance. Therefore, the temperature change can be detected with high sensitivity.

[0086] Fig. 9 FIG. 5 is a diagram showing a part of the temperature detection unit 5. Fig. 9 As shown, the temperature detection unit 5 includes a first input terminal 501, a second input terminal 502, a first output terminal 503, and a second output terminal 504 in addition to the aforementioned first wiring unit 50. The first input terminal 501 and the second input terminal 502 are connected to, for example, a power supply circuit that applies a predetermined voltage to the second wiring unit 60. The first input terminal 501 is connected to an end of one side of the first wiring unit 50 via a wiring 505, and the second input terminal 502 is connected to an end of the other side of the first wiring unit 50 via a wiring 506. The first output terminal 503 and the second output terminal 504 are, for example, terminals for taking out an output voltage based on the resistance value of the first wiring unit 50, and are connected to Figure 2 The temperature acquisition unit 41 is connected to a detection circuit (not shown) included in the temperature acquisition unit 41.

[0087] when Figure 5 When the temperature changes on the first wiring section 50 shown, an external force is applied via the second vibration plate 132 according to the pressure of the absorption chamber S2. Stress corresponding to the external force acts on the first wiring section 50. As a result, the first wiring section 50 is deformed, and the resistance value changes. By using this resistance value, the temperature of the absorption chamber S2 can be detected. The first wiring section 50 is formed using metal, semiconductor, etc.

[0088] The temperature of the absorption chamber S2 is detected by utilizing the property that the resistance value of metals, semiconductors, etc. changes with temperature. Figure 2 The temperature acquisition unit 41 acquires the temperature of the absorption chamber S2 based on the resistance value of the first wiring unit 50. For example, the temperature acquisition unit 41 has a detection circuit that acquires a signal based on the resistance value of the first wiring unit 50. The temperature acquisition unit 41 detects the temperature of the absorption chamber S2 based on the corresponding relationship between the resistance value and the temperature of the detection resistor 401. By providing the liquid ejection head 1 with the first wiring unit 50 and the temperature acquisition unit 41, it is possible to detect the temperature of a desired portion such as the absorption chamber S2.

[0089] In addition, the first wiring section 50 is provided at a position not corresponding to the absorption chamber S2. Therefore, the first wiring section 50 does not receive resistance changes caused by the pressure of the absorption chamber S2, but only receives resistance changes caused by the temperature of the absorption chamber S2. Therefore, by using the first wiring section 50, it is possible to obtain a resistance value based only on the temperature of the absorption chamber S2 with high accuracy.

[0090] Furthermore, the first wiring section 50 is disposed at a position that does not overlap with the pressure chamber S1 and the absorption chamber S2 when viewed in a planar manner. Therefore, the resistance value of the first wiring section 50 is not easily affected by the vibration of the first vibration plate 131 and the second vibration plate 132. Since the first wiring section 50 is disposed at a position that does not overlap with the pressure chamber S1 and the absorption chamber S2, it is not easily affected by the pressure of the pressure chamber S1 and the absorption chamber S2. Therefore, the temperature near the absorption chamber S2 can be measured with high accuracy based on the resistance value of the first wiring section 50.

[0091] In particular, the first wiring section 50 is disposed between the pressure chamber S1 and the absorption chamber S2 in the X2 direction when viewed in a plan view. Therefore, the first wiring section 50 can be disposed near the absorption chamber S2. Therefore, the temperature of the absorption chamber S2 can be detected with high accuracy.

[0092] Moreover, the pressure acquisition unit 42 acquires the pressure of the absorption chamber S2 based on the resistance value of the second wiring unit 60 and the temperature acquired by the temperature acquisition unit 41. The second wiring unit 60 is provided corresponding to the absorption chamber S2 to withstand the resistance change caused by the pressure of the absorption chamber S2 and the temperature near the absorption chamber S2. In contrast, since the first wiring unit 50 is provided at a position not corresponding to the absorption chamber S2, it does not withstand the resistance change caused by the pressure of the absorption chamber S2, but only withstands the resistance change caused by the temperature near the absorption chamber S2. Therefore, by obtaining the difference between the resistance value of the second wiring unit 60 and the resistance value of the first wiring unit 50, it is possible to detect only the pressure of the absorption chamber S2 without being affected by the temperature. Therefore, the pressure of the absorption chamber S2 can be measured with high precision. In this way, by using the resistance value of the second wiring unit 60, the influence of temperature change can be eliminated in the detection of the absorption chamber S2. Therefore, the detection accuracy of the pressure can be improved.

[0093] It is difficult to clearly separate the resistance change caused by the strain due to the pressure change in the absorption chamber S2 and the resistance change caused by the strain due to the temperature change. The rate of change when the resistance value R of the second wiring portion 60 changes to R+ΔR is expressed by equation [1].

[0094] ΔR / R=kΔε+αΔT…[1]

[0095] In formula [1], k is the sensitivity coefficient. Δε is the deformation change. α is the resistance temperature coefficient. ΔT is the temperature change.

[0096] As can be seen from formula [1], the resistance value R of the second wiring portion 60 is caused by the deformation change Δε due to pressure and the temperature change ΔT. Therefore, in order to detect the deformation caused by pressure with high accuracy, it is preferable to reduce the influence of temperature change. In order to reduce the influence of temperature change, a material with a large sensitivity coefficient k and a small resistance temperature coefficient α can be selected. As such a material, for example, NiCr (nickel-chromium alloy) can be cited.

[0097] However, even if a material such as NiCr with a large sensitivity coefficient k and a small resistance temperature coefficient α is used, the influence of temperature changes will remain. In addition, for example, when Pt (platinum) is used as a material with a large sensitivity coefficient k and easy to form the second wiring portion 60, the influence of temperature changes cannot be ignored.

[0098] In this embodiment, as described above, the second wiring section 60 and the first wiring section 50 are provided. The second wiring section 60 is provided corresponding to the absorption chamber S2, and the resistance change of the second wiring section 60 is represented by the above formula [1]. On the other hand, the first wiring section 50 is provided at a position that does not correspond to the absorption chamber S2. Therefore, the resistance change of the first wiring section 50 is represented by the following formula [2], which assumes that Δε=0 in the above formula [1].

[0099] ΔR / R=αΔT…[2]

[0100] The resistance change due to temperature and pressure is measured using the second wiring section 60, and the resistance change due to temperature alone is measured using the first wiring section 50. Furthermore, by subtracting the resistance change due to pressure alone from the resistance change due to the second wiring section 60, the resistance change due to pressure alone can be obtained.

[0101] In this way, by using the second wiring section 60 and the first wiring section 50, the resistance change caused by the deformation due to the pressure change in the absorption chamber S2 and the resistance change caused by the deformation due to the temperature change can be clearly separated. In addition, the influence of the temperature change can be eliminated in the pressure detection. Therefore, the detection accuracy of the pressure in the absorption chamber S2 can be improved.

[0102] In addition, although the first wiring section 50 and the second wiring section 60 can also be formed of different materials, it is preferable to form them with the same material. By making the materials the same, the difference in temperature and pressure characteristics caused by the difference in materials can be reduced. Therefore, the detection accuracy of pressure can be improved. That is, the accuracy of pressure calculation can be improved.

[0103] Conductive materials can be used as materials for the first wiring section 50 and the second wiring section 60. Specifically, for example, conductive metal oxides such as ITO (indium tin oxide), metals such as Pt, Ir (iridium), Au (gold), and Ti (titanium), and alloys such as NiCr can be used. In addition, the first wiring section 50 and the second wiring section 60 can be either single-layer or multi-layer.

[0104] In addition, the first wiring section 50 and the second wiring section 60 are preferably formed of the same material as the second electrode 33 of the first piezoelectric body 31. By forming the first wiring section 50 and the second wiring section 60 with the same material, the second electrode 33, the first wiring section 50 and the second wiring section 60 can be formed in the same process, which is relatively simple. In addition, the first wiring section 50 and the second wiring section 60 can also be formed of materials different from the second electrode 33.

[0105] And, if Figure 5 As shown in the figure, the first piezoelectric body 31 and the first electrode 32 are arranged on the first wiring part 50 and the second wiring part 60. Therefore, the first wiring part 50 and the second wiring part 60 are less susceptible to the influence of humidity than when the first piezoelectric body 31 and the first electrode 32 are not arranged on the first wiring part 50 and the second wiring part 60. Therefore, the detection accuracy of pressure can be improved.

[0106] In addition, as described above, at least a plurality of pressure chambers S1 and an absorption chamber S2 commonly connected to the plurality of pressure chambers S1 are provided on the pressure chamber substrate 12. Since the volume of the absorption chamber S2 is larger than the volume of each pressure chamber S1, the plane area of ​​the second vibration plate 132 forming the absorption chamber S2 can be made larger than the plane area of ​​each first vibration plate 131 forming each pressure chamber S1. Therefore, the displacement of the second vibration plate 132 can be made larger than the displacement of the first vibration plate 131. Therefore, the absorption efficiency achieved by the absorption chamber S2 can be improved. In addition, by being able to detect the pressure of an absorption chamber S2 commonly connected to a plurality of pressure chambers S1, it is possible to detect the pressure of the absorption chamber S2 caused by the influence of the plurality of pressure chambers S1, rather than the pressure of each pressure chamber S1. Therefore, the pressure can be used to detect various adverse conditions such as whether insufficient ink supply has occurred.

[0107] According to the present embodiment described above, the pressure in the vicinity of the pressure chamber S1 can be acquired by utilizing the absorption chamber S2 which is a space for absorbing vibration of ink.

[0108] 2. Second Implementation

[0109] In the following exemplary embodiments, elements having the same actions and functions as those of the first embodiment are assigned the same reference numerals as those of the first embodiment, and detailed descriptions thereof are appropriately omitted.

[0110] Fig.10 It is a plan view showing a first wiring portion 50A according to the second embodiment. Fig.10 The first wiring portion 50A includes a second folded portion 53 and a second straight portion 54. The second folded portion 53 has a third folded shape that extends in the X2 direction and is sequentially folded back in the Y2 direction. The second straight portion 54 has a straight shape that extends in the Y2 direction.

[0111] The second pleated portion 53 includes a plurality of fifth portions 531 and a plurality of sixth portions 532. The plurality of fifth portions 531 are portions extending in the X2 direction, which are separated from each other and arranged in the Y2 direction. The plurality of sixth portions 532 are portions extending in the Y2 direction. Each sixth portion 532 is disposed between two adjacent fifth portions 531 and connects the two adjacent fifth portions 531. The plurality of sixth portions 532 are alternately disposed at the ends of the fifth portion 531 in the X1 direction and the ends in the X2 direction. The sixth portion 532 located closest to the Y1 direction among the plurality of sixth portions 532 is set as the first, and the plurality of sixth portions 532 are counted in the Y2 direction. In this case, for example, the odd-numbered sixth portions 532 among the plurality of sixth portions 532 are connected to the ends of the fifth portion 531 in the X1 direction. The even-numbered sixth portions 532 among the plurality of sixth portions 532 are connected to the ends of the fifth portion 531 in the X2 direction.

[0112] The second folded portion 53 of the first wiring portion 50A is configured to have a third folded shape that extends along the X2 direction and is sequentially folded back toward the Y1 direction. Therefore, by making the second folded portion 53 into the third folded shape, the first wiring portion 50A can be configured to be thinner and longer. Therefore, the first wiring portion 50A can be made higher in resistance.

[0113] In addition, the third fold shape of the second fold portion 53 of the first wiring portion 50A is shorter than the second fold shape of the first fold portion 61 of the second wiring portion 60, which extends along the X2 direction. That is, the length of the fifth portion 531 in the X2 direction is shorter than the length of the first portion 611 in the X2 direction. Therefore, the initial value of the resistance is different in the first wiring portion 50A and the second wiring portion 60. Even when the initial value of the resistance is different, the change rate, that is, ΔR / R, is common in the first wiring portion 50A and the second wiring portion 60. Therefore, by subtracting the relationship between the above-mentioned formulas [1] and [2], it is possible to detect only the resistance change caused by pressure.

[0114] The second wiring section 60 is used to obtain the resistance value by the change of deformation based on the vibration of the second vibration plate 132, and detect the pressure of the absorption chamber S2. Therefore, the second wiring section 60 is preferably arranged in a wider area. On the other hand, if the first wiring section 50A is set to the same shape as the second wiring section 60, the plane area of ​​the vibration plate 13 may become larger. Therefore, it is preferred that the plane area of ​​the first wiring section 50A is smaller than the plane area of ​​the second wiring section 60. From this point of view, it is preferred that the length of the fifth part 531 in the X2 direction is shorter than the length of the first part 611 in the X2 direction as in the present embodiment.

[0115] 3. Third Implementation

[0116] In the following exemplary embodiments, elements having the same actions and functions as those of the first embodiment are assigned the same reference numerals as those of the first embodiment, and detailed descriptions thereof are appropriately omitted.

[0117] Fig.11 1 is a plan view showing a first wiring portion 50B according to the third embodiment. Fig.11 The first wiring portion 50B includes a third folded portion 55 and a third straight portion 56. The third folded portion 55 is a third folded shape that is sequentially folded back toward the Y2 direction while extending along the X2 direction. The third straight portion 56 is a straight line extending along the Y2 direction.

[0118] The third pleated portion 55 includes a plurality of seventh portions 551 and a plurality of eighth portions 552. The plurality of seventh portions 551 are portions extending in the X2 direction, which are separated from each other and arranged in the Y2 direction. The plurality of eighth portions 552 are portions extending in the Y2 direction. Each eighth portion 552 is arranged between two adjacent seventh portions 551 and connects the two adjacent seventh portions 551. The plurality of eighth portions 552 are alternately arranged at the ends of the seventh portion 551 in the X1 direction and the ends in the X2 direction. The eighth portion 552 located closest to the Y1 direction among the plurality of eighth portions 552 is set as the first, and the plurality of eighth portions 552 are counted in the Y2 direction. In this case, for example, the odd-numbered eighth portions 552 among the plurality of eighth portions 552 are connected to the ends of the seventh portion 551 in the X1 direction. The even-numbered eighth portions 552 among the plurality of eighth portions 552 are connected to the ends of the seventh portion 551 in the X2 direction.

[0119] The third folded portion 55 of the first wiring portion 50B is configured to have a fourth folded shape that extends along the X2 direction and then folds back in the Y1 direction. Therefore, by configuring the third folded portion 55 to have the fourth folded shape, the first wiring portion 50B can be configured to be thinner and longer. Therefore, the first wiring portion 50B can be made higher in resistance.

[0120] The fourth pleated shape of the third pleated portion 55 is identical to the first pleated shape of the first pleated portion 61 of the second wiring portion 60. Therefore, the third pleated portion 55 of the first wiring portion 50B is configured to have a fourth pleated shape such that the length of the portion extending along the X2 direction of the third pleated portion 55 is identical to the length of the portion extending along the X2 direction of the first pleated shape of the first pleated portion 61. That is, the length of the seventh portion 551 in the X2 direction is identical to the length of the first portion 611 in the X2 direction.

[0121] By making the fourth pleat shape of the third pleat portion 55 the same as the first pleat shape of the first pleat portion 61, when no pressure is applied to the first wiring portion 50B and the second wiring portion 60 and the temperature is in a balanced state, the initial resistance values ​​of the first wiring portion 50B and the second wiring portion 60 are the same. Therefore, the pressure change in the absorption chamber S2 can be detected by simple subtraction of the resistance value of the first wiring portion 50B and the resistance value of the second wiring portion 60.

[0122] 4. Modifications

[0123] The above-described embodiments may be modified in various ways. In the following, specific modified methods that can be applied to the above-described embodiments are illustrated. Two or more methods arbitrarily selected from the following examples may be appropriately combined within a range that is not contradictory to each other.

[0124] Fig.12 1 is a block diagram of a liquid ejection device 100a of a modified example. The liquid ejection device 100a includes a liquid ejection head 1a and a control unit 20a. The control unit 20a is provided with a drive circuit 40, a temperature acquisition unit 41, and a pressure acquisition unit 42. The temperature acquisition unit 41 and the pressure acquisition unit 42 are not provided in the liquid ejection head 1a.

[0125] like Fig.12 As shown, the drive circuit 40, the temperature acquisition unit 41, and the pressure acquisition unit 42 may be partially or entirely provided on the control unit 20. With the liquid ejection device 100a, as in the respective embodiments, the pressure near the pressure chamber S1 can be acquired by using the absorption chamber S2 which is a space for absorbing vibrations of the ink.

[0126] The shapes of the “second wiring portion” and the “first wiring portion” are preferably shapes that can easily withstand stress caused by deformation of the first vibration plate 131 or the second vibration plate 132 , and are not limited to the corrugated shapes.

[0127] Furthermore, the “liquid ejection head” may be a circulation type head having a so-called circulation flow path.

[0128] Fig.13 It is a cross-sectional view of a part of the liquid ejection head 10 according to a modified example. Fig.13 The liquid ejection head 10 shown has a nozzle substrate 11, a pressure chamber substrate 120, a vibration plate 130, a sealing substrate 140, a housing 150, a wiring substrate 49, a first piezoelectric element 3, a pressure detection section 6, a temperature detection section 5 and a second piezoelectric element 7. Fig.13 The liquid ejection head 10 is a circulation type head having a so-called circulation flow path.

[0129] The pressure chamber substrate 120 is a laminate of a third substrate 124 and a fourth substrate 125. These substrates are manufactured by processing semiconductor substrates such as single crystal silicon substrates, for example. In addition to a plurality of pressure chambers S1, absorption chambers S2, a plurality of first communication channels R1, and a second communication channel R2, a plurality of fourth communication channels R4, a plurality of fifth communication channels R5, a sixth communication channel R6, and a discharge side absorption chamber S3 are formed on the pressure chamber substrate 120. The absorption chamber S2 is a supply side absorption chamber.

[0130] One first communication flow channel R1 is connected to one fifth communication flow channel R5 via one fourth communication flow channel R4. Each fourth communication flow channel R4 overlaps with the nozzle N when viewed in plan. Each fifth communication flow channel R5 is connected to the discharge side absorption chamber S3. The discharge side absorption chamber S3 overlaps with the second piezoelectric element 7 when viewed in plan. Multiple discharge side absorption chambers S3 are connected to the sixth communication flow channel R6.

[0131] The vibration plate 130 includes a third vibration plate 133 in addition to the plurality of first vibration plates 131 and the second vibration plate 132. The third vibration plate 133 is a portion of the vibration plate 130 that overlaps with the discharge-side absorption chamber S3 in plan view.

[0132] The housing 150 is in contact with the sealing substrate 140. In addition, the housing 150 and the sealing substrate 140 may be integrated. The third communication flow channel R3 and the seventh communication flow channel R7 are formed on the housing 150. The common ink chamber R0 is formed by the seventh communication flow channel R7 and the sixth communication flow channel R6.

[0133] In addition to the first space H1 and the wiring space H0, a second space H3 is formed on the sealing substrate 140. The second piezoelectric element 7 is arranged in the second space H3. The second piezoelectric element 7 is arranged on the surface of the third vibration plate 133 on the opposite side to the discharge side absorption chamber S3. The second piezoelectric element 7 is used to detect the pressure of the discharge side absorption chamber S3. The second piezoelectric element 7 is deformed according to the third vibration plate 133 that is bent according to the pressure of the discharge side absorption chamber S3.

[0134] The second piezoelectric element 7 has a third electrode 72, a second piezoelectric body 71, and a fourth electrode 73. These components are long and narrow along the Y axis. The fourth electrode 73, the second piezoelectric body 71, and the third electrode 72 are stacked in this order from the third vibration plate 133. The second piezoelectric body 71 is formed using a known piezoelectric material such as lead zirconate titanate. The third electrode 72 and the fourth electrode 73 are formed using a conductive material such as platinum or iridium, respectively. The second piezoelectric element 7 is not a component that applies pressure to the liquid in the flow channel, but a component for absorbing vibration.

[0135] In addition, although the third vibration plate 133, the second piezoelectric element 7, and the discharge side absorption chamber S3 are long and narrow along the Y axis and are provided with respect to the plurality of pressure chambers S1, these components may be provided for each pressure chamber S1. Therefore, the third vibration plate 133, the second piezoelectric element 7, and the discharge side absorption chamber S3 may each be provided in plurality.

[0136] In the liquid ejection head 10, ink flows to the pressure chamber S1 via the common ink chamber R and the absorption chamber S2. The pressure of the pressure chamber S1 is changed by driving the first piezoelectric element 3, and the change in pressure causes the ink to be ejected from the nozzle N as ink droplets via the first communication flow channel R1 and the fourth communication flow channel R4. At the same time, the ink flows back through the fifth communication flow channel R5, the discharge side absorption chamber S3, and the common ink chamber R0. In this way, the ink is circulated.

[0137] Furthermore, in the liquid ejection head 10, an absorption chamber S2 is provided in the X2 direction relative to the pressure chamber S1, and a discharge side absorption chamber S3 is provided in the X1 direction relative to the pressure chamber S1. That is, a vibration absorbing mechanism is provided at the supply side and the discharge side of the ink relative to the pressure chamber S1. Furthermore, the distance between the absorption chamber S2 and the pressure chamber S1 is shorter than the distance between the discharge side absorption chamber S3 and the pressure chamber S1. A pressure detecting unit 6 is provided relative to the absorption chamber S2 closer to the pressure chamber S1. Therefore, by using the absorption chamber S2 closer to the pressure chamber S1 to detect the pressure near the pressure chamber S1, the behavior of the ink corresponding to the pressure of the pressure chamber S1 can be detected with better accuracy.

[0138] In addition to equipment dedicated to printing, "liquid ejection devices" can also be used in various equipment such as fax machines or copiers. The use of liquid ejection devices is not limited to printing. For example, a liquid ejection device that ejects a solution of a color material can be used as a manufacturing device for forming a color filter for a display device such as a liquid crystal display panel. In addition, a liquid ejection device that ejects a solution of a conductive material can be used as a manufacturing device for forming wiring and electrodes of a wiring substrate. In addition, a liquid ejection device that ejects a solution of an organic substance related to a living body can be used as a manufacturing device for manufacturing a biochip, for example.

[0139] Although the present invention has been described above based on preferred embodiments, the present invention is not limited to the aforementioned embodiments. In addition, the structure of each part of the present invention can be replaced with an arbitrary structure that exerts the same function as the aforementioned embodiments, and an arbitrary structure can be added.

[0140] Explanation of symbols

[0141] 1…liquid ejection head; 1a…liquid ejection head; 3…first piezoelectric element; 5…temperature detection unit; 6…pressure detection unit; 9…liquid container; 11…nozzle substrate; 12…pressure chamber substrate; 13…vibration plate; 14…sealing substrate; 20…control unit; 20a…control unit; 21…control unit; 22…medium transport mechanism; 23…storage unit; 24…moving mechanism; 25…driving signal generating circuit; 31…first piezoelectric body; 32…first piezoelectric electrode; 33…second electrode; 40…drive circuit; 41…temperature acquisition unit; 42…pressure acquisition unit; 49…wiring substrate; 50…first wiring unit; 50A…first wiring unit; 50B…first wiring unit; 51…third portion; 52…fourth portion; 53…second folded portion; 54…second straight portion; 55…third folded portion; 56…third straight portion; 60…second wiring unit; 61…first folded portion; 62…first straight portion; 63…first electrode resistance element; 64…second resistance element; 65…third resistance element; 90…medium; 100…liquid ejection device; 100a…liquid ejection device; 121…first substrate; 122…second substrate; 131…first vibration plate; 132…second vibration plate; 141…filter; 242…transport body; 244…transport belt; 310…dielectric film; 401…detection resistor; 501…first input terminal; 502…second input terminal; 50 3…first output terminal; 504…second output terminal; 505…wiring; 506…wiring; 507…wiring; 508…wiring; 531…fifth portion; 532…sixth portion; 551…seventh portion; 552…eighth portion; 611…first portion; 612…second portion; G…cutout; H0…space for wiring; H1…first space; N…nozzle; R0…common ink chamber; R1…first communicating flow channel; R2…second communicating flow channel.

Claims

1. A liquid ejection head, characterized in that: have: a nozzle substrate provided with a nozzle for ejecting liquid; a pressure chamber substrate having a pressure chamber and an absorption chamber, wherein the pressure chamber applies pressure to the liquid for ejecting the liquid from the nozzle, and the absorption chamber is adjacent to the second direction of the pressure chamber and absorbs vibration of the liquid generated when the pressure is applied to the liquid in the pressure chamber; a first vibration plate provided corresponding to the pressure chamber and vibrating to apply pressure to the liquid; a second vibration plate disposed corresponding to the absorption chamber and vibrating to absorb the pressure of the liquid; a second wiring portion disposed at a position corresponding to the absorption chamber; The pressure acquisition unit acquires the pressure of the absorption chamber based on the resistance value of the second wiring unit.

2. The liquid ejection head according to claim 1, wherein: The pressure chamber substrate includes at least a plurality of the pressure chambers arranged in a first direction intersecting the second direction, and one absorption chamber connected in common to the plurality of pressure chambers.

3. The liquid ejection head according to claim 2, wherein: The second wiring portion is configured to have a second pleated shape that is sequentially folded back while extending along the second direction.

4. The liquid ejection head according to claim 2, wherein: Also features: a first wiring portion disposed at a position not corresponding to the absorption chamber; A temperature acquisition unit acquires the temperature of the absorption chamber based on the resistance value of the first wiring unit.

5. The liquid ejection head according to claim 4, wherein: The pressure acquisition unit acquires the pressure of the absorption chamber based on the resistance value of the second wiring unit and the temperature acquired by the temperature acquisition unit.

6. The liquid ejection head according to claim 4, wherein: When viewed from a vertical direction intersecting the first direction and the second direction, The second wiring portion is provided at a position overlapping with the absorption chamber, The first wiring portion is provided at a position that does not overlap with the pressure chamber and the absorption chamber.

7. The liquid ejection head according to claim 6, wherein: When viewed from the up and down direction, The first wiring portion is provided at a position between the pressure chamber and the absorption chamber in the second direction.

8. The liquid ejection head according to claim 4, wherein: The first wiring portion is configured to have a first corrugated shape that is sequentially folded back while extending along the first direction.

9. The liquid ejection head according to claim 4, wherein: The second wiring portion is configured to have a second pleated shape that is sequentially folded back while extending along the second direction. The first wiring portion is configured to have a third pleated shape that is sequentially folded back while extending along the second direction, wherein the length of a portion of the third pleated shape extending along the second direction is shorter than that of the second pleated shape.

10. The liquid ejection head according to claim 4, wherein: The second wiring portion is configured to have a second pleated shape that is sequentially folded back while extending along the second direction. The first wiring portion is configured to have a fourth pleated shape that is sequentially folded back while extending along the second direction, wherein the fourth pleated shape has the same length as a portion of the second pleated shape extending along the second direction.

11. The liquid ejection head according to claim 1, wherein The first vibration plate and the second vibration plate are not separated but are formed using one continuous member.

12. The liquid ejection head according to claim 4, wherein: The first wiring portion and the second wiring portion are formed using the same material.

13. The liquid ejection head according to claim 4, wherein: Also features: a first piezoelectric body provided at a position corresponding to the pressure chamber and above the first vibration plate; a first electrode disposed at an upper side of the first piezoelectric body; a second electrode disposed at a lower side of the first piezoelectric body, The first wiring portion and the second wiring portion are formed using the same material as the second electrode.

14. A liquid ejection device, characterized in that: It has a liquid ejection head and a pressure acquisition unit, wherein The liquid ejection head comprises: a nozzle substrate provided with a nozzle for ejecting liquid; a pressure chamber substrate having a pressure chamber and an absorption chamber, wherein the pressure chamber applies pressure to the liquid for ejecting the liquid from the nozzle, and the absorption chamber is adjacent to the second direction of the pressure chamber and absorbs vibration of the liquid generated when the pressure is applied to the liquid in the pressure chamber; a first vibration plate provided corresponding to the pressure chamber and vibrating to apply pressure to the liquid; a second vibration plate disposed corresponding to the absorption chamber and vibrating to absorb the pressure of the liquid; a second wiring portion disposed at a position corresponding to the absorption chamber; The pressure acquisition unit acquires the pressure of the absorption chamber based on the resistance value of the second wiring unit.

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