Driving substrate, liquid ejection head, and liquid ejection recording apparatus

Abstract

The present application provides a driving substrate capable of improving the discharge performance of a liquid while reducing manufacturing costs. The driving substrate according to an embodiment of the present disclosure is applied to a liquid ejection head and outputs a driving signal to an ejection section, and includes: a first wiring layer and a second wiring layer that face each other in a direction orthogonal to a substrate surface; one or more driving devices mounted on the first wiring layer and configured to generate the driving signal; a first power supply wiring provided on the first wiring layer and configured to supply a driving power supply wiring to the driving device; a differential line provided on the first wiring layer and configured to transmit a differential signal to the driving device; and a second power supply wiring provided on the second wiring layer, the second power supply wiring being electrically connected to the first power supply wiring via a first through-hole and facing a first region in the differential line. A wiring width of the second power supply wiring is greater than a line width of the first region in the differential line.

Description

Technical Field

[0001] This disclosure relates to a drive substrate, a liquid jet head, and a liquid jet recording device. Background Technology

[0002] Liquid jet recording devices equipped with liquid jet heads are used in various fields, and various types of jet heads have been developed as liquid jet heads (for example, see Patent Document 1).

[0003] [Existing Technical Documents]

[0004] [Patent Documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 2018-103612. Summary of the Invention

[0006] [The problem the invention aims to solve]

[0007] In such liquid ejection heads, there is a general requirement to improve liquid ejection performance or reduce manufacturing costs. There is a need to provide a drive substrate, liquid ejection head, and liquid ejection recording device that can improve liquid ejection performance while reducing manufacturing costs.

[0008] [Solution to the problem]

[0009] An embodiment of this disclosure discloses a driving substrate suitable for a liquid jet head having a jetting section for jetting liquid, and for outputting a driving signal for jetting the liquid to the jetting section. The substrate includes: a first wiring layer and a second wiring layer, which are positioned opposite each other along a direction orthogonal to the substrate surface; one or more driving devices mounted on the first wiring layer and generating the driving signal; a first power supply wiring disposed on the first wiring layer and used to supply driving power to the driving devices; a differential line disposed on the first wiring layer and used to transmit a differential signal to the driving devices; and a second power supply wiring disposed on the second wiring layer, electrically connected to the first power supply wiring via a first via, and opposite to a first region in the differential line. Furthermore, the width of the second power supply wiring is greater than the width of the first region in the differential line.

[0010] An embodiment of the liquid injection head disclosed herein includes: one or more drive substrates as described in the embodiment of the present disclosure and the injection section described above.

[0011] The liquid jet recording apparatus according to one embodiment of the present disclosure includes: the liquid jet head according to one embodiment of the present disclosure described above.

[0012] [Invention Effects]

[0013] According to an embodiment of the present disclosure, the driving substrate, liquid jet head, and liquid jet recording device can improve the liquid ejection performance and reduce manufacturing costs. Attached Figure Description

[0014] Figure 1 This is a block diagram illustrating a schematic configuration example of a liquid injection device according to an embodiment of the present disclosure.

[0015] Figure 2 It is shown schematically. Figure 1 A perspective view of a schematic configuration example of a liquid injection head.

[0016] Figure 3 It is shown schematically. Figure 2 A cross-sectional view of an example of the configuration of a liquid injection head.

[0017] Figure 4A It is shown schematically. Figure 2 , Figure 3 A plan view showing a detailed configuration example of the flexible substrate.

[0018] Figure 4B It is shown schematically. Figure 2 , Figure 3 A plan view showing a detailed configuration example of another flexible substrate.

[0019] Figure 5 It is shown schematically. Figure 4B A plan view showing an example of the configuration of wiring and other components within a flexible substrate.

[0020] Figure 6 It is shown schematically. Figure 5 A plan view showing a detailed configuration example of each wiring element.

[0021] Figure 7 It is shown schematically. Figure 5 A plan view showing a detailed configuration example of each wiring element.

[0022] Figure 8 It is shown schematically. Figure 6 , Figure 7 The cross-sectional view of the configuration example shown.

[0023] Figure 9A This is a schematic cross-sectional view showing an example of the configuration of a typical transmission line.

[0024] Figure 9B This is a schematic cross-sectional view showing another example of the configuration of a typical transmission line.

[0025] Figure 10This is a plan view schematically showing an example of the configuration of wiring and other components within a flexible substrate involved in Modified Example 1.

[0026] Figure 11 This is a plan view schematically showing an example of the configuration of wiring and other components within a flexible substrate involved in Modified Example 1.

[0027] Figure 12 This is a plan view schematically showing an example of the configuration of wiring and other components within the flexible substrate involved in Modified Example 2.

[0028] Figure 13 It is shown schematically. Figure 12 A plan view showing a detailed example of the composition of a portion of the area shown. Detailed Implementation

[0029] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. Furthermore, the description will proceed in the following order.

[0030] 1. Implementation method (example in which a second power supply wiring is provided as an inner plane relative to the differential line)

[0031] 2. Variations

[0032] Variation 1 (an example where a second grounding wiring is further provided as the inner layer described above)

[0033] Variation 2 (an example where a return wiring is further configured to become the return path of the current)

[0034] 3. Other variations

[0035] <1. Implementation Method>

[0036] [Brief Components of Printer 5]

[0037] Figure 1 A schematic diagram illustrates a schematic configuration example of a printer 5, which is a liquid jet recording apparatus according to one embodiment of this disclosure. Figure 2 A schematic 3D diagram is shown as Figure 1 The inkjet head 1 of the liquid jet head shown is a schematic example of its configuration. Figure 3 A schematic diagram is shown in the cross-sectional view (Y-Z cross-sectional view). Figure 2 The illustration shows an example of the configuration of the inkjet head 1. Furthermore, the scale of each component in the accompanying drawings used in this specification has been appropriately altered to make each component a recognizable size.

[0038] Printer 5 uses ink 9, described later, to record on the medium (e.g., Figure 1The recording paper P shown is used by an inkjet printer for recording (printing) images or characters, etc. For example... Figure 1 As shown, the printer 5 includes an inkjet head 1, a printing control unit 2, and an ink tank 3.

[0039] Furthermore, inkjet head 1 corresponds to a specific example of the "liquid jet head" in this disclosure, and printer 5 corresponds to a specific example of the "liquid jet recording device" in this disclosure. Additionally, ink 9 corresponds to a specific example of the "liquid" in this disclosure.

[0040] (A. Printing Control Department 2)

[0041] The printing control unit 2 supplies various information (data) to the inkjet head 1. Specifically, such as... Figure 1 As shown, the printing control unit 2 supplies printing control signals Sc to the inkjet head 1 (such as the driving device 41 described later).

[0042] In addition, the printing control signal Sc includes, for example, image data, ejection timing signals, and power supply voltage for operating the inkjet head 1.

[0043] (B. Ink can 3)

[0044] Ink container 3 is the container that internally holds ink 9. For example... Figure 1 As shown, the ink 9 in the ink tank 3 is supplied to the inkjet head 1 (the ejection section 11 described later) via the ink supply tube 30. Furthermore, such an ink supply tube 30 is, for example, made of a flexible hose.

[0045] (C. Inkjet head 1)

[0046] like Figure 1 As shown by the dashed arrow, the inkjet head 1 is a head that records images or characters by ejecting (ejecting) droplets of ink 9 from multiple nozzle holes Hn onto the recording paper P. For example, as... Figure 2 , Figure 3 As shown, the inkjet head 1 includes: a jetting section 11; an I / F (interface) substrate 12; four flexible substrates 13a, 13b, 13c, and 13d; and two cooling units 141 and 142.

[0047] (C-1. I / F substrate 12)

[0048] like Figure 2 , Figure 3 As shown, the I / F substrate 12 includes: two connectors 10; four connectors 120a, 120b, 120c, and 120d; and a circuit configuration area 121.

[0049] like Figure 2As shown, connector 10 is the part (connector part) that inputs the aforementioned printing control signal Sc supplied from the printing control unit 2 to the inkjet head 1 (each flexible substrate 13a, 13b, 13c, 13d described later).

[0050] Connectors 120a, 120b, 120c, and 120d are respectively the parts that electrically connect the I / F substrate 12 to the flexible substrates 13a, 13b, 13c, and 13d (connector parts).

[0051] The circuit configuration area 121 is an area on the I / F substrate 12 where various circuits are configured. Furthermore, such circuit configuration areas can also be provided in other areas on the I / F substrate 12.

[0052] (C-2. Jet section 11)

[0053] like Figure 1 As shown, the ejection section 11 is a portion having multiple nozzle holes Hn from which ink 9 is ejected. The ejection of ink 9 occurs in accordance with the drive signal Sd (drive voltage Vd) supplied from the drive device 41 (described later) on each of the flexible substrates 13a, 13b, 13c, and 13d (see reference). Figure 1 ).

[0054] like Figure 1 As shown, such a jet section 11 is configured to include an actuator plate 111 and a nozzle plate 112.

[0055] (Nozzle plate 112)

[0056] The nozzle plate 112 is a plate made of a film material such as polyimide or a metal material, such as... Figure 1 As shown, there are multiple nozzle holes Hn as described above. These nozzle holes Hn are formed side by side at predetermined intervals, for example, in a circular shape.

[0057] Specifically, in Figure 2 In the example of the injection section 11 shown, the plurality of nozzle holes Hn in the nozzle plate 112 are composed of a plurality of nozzle rows (4 nozzle rows) arranged along the column direction (X-axis direction). In addition, these 4 nozzle rows are arranged side by side with each other along a direction orthogonal to the column direction (Y-axis direction).

[0058] (Actuator plate 111)

[0059] The actuator plate 111 is, for example, a plate made of a piezoelectric material such as PZT (lead zirconate titanate). Multiple channels (pressure chambers) are provided on this actuator plate 111. These channels, which are used to apply pressure to the ink 9, are arranged side-by-side in a parallel manner with predetermined intervals. Each channel is divided by a drive wall (not shown) made of a piezoelectric material, which appears as a concave groove in cross-section.

[0060] Such a channel contains an outlet channel for dispensing ink 9 and a pseudo-channel (non-dispensing channel) for not dispensing ink 9. In other words, the outlet channel is filled with ink 9, while the pseudo-channel is not filled with ink 9. Furthermore, the ink 9 fills each outlet channel, for example, via a flow path (common flow path) that is connected to each of such outlet channels. In addition, each outlet channel is individually connected to a nozzle orifice Hn on the nozzle plate 112, while each pseudo-channel is not connected to a nozzle orifice Hn. These outlet channels and pseudo-channels are arranged alternately side by side along the aforementioned column direction (X-axis direction).

[0061] Furthermore, driving electrodes are respectively provided on the opposing inner surfaces of the aforementioned driving wall. These driving electrodes have a common electrode (shared electrode) provided on the inner surface facing the ejection channel and an active electrode (individual electrode) provided on the inner surface facing the pseudo-channel. These driving electrodes are electrically connected to the driving device 41 described later via flexible substrates 13a, 13b, 13c, and 13d. Thus, the aforementioned driving voltage Vd (driving signal Sd) is applied to each driving electrode from the driving device 41 via each flexible substrate 13a, 13b, 13c, and 13d (see...). Figure 1 ).

[0062] (C-3. ​​Flexible substrates 13a, 13b, 13c, 13d)

[0063] like Figure 2 , Figure 3 As shown, flexible substrates 13a, 13b, 13c, and 13d are substrates electrically connecting the I / F substrate 12 and the ejection section 11. Each of these flexible substrates 13a, 13b, 13c, and 13d individually controls the ejection action of ink 9 from each of the four rows of nozzles in the aforementioned nozzle plate 112. Furthermore, for example, as... Figure 3 As indicated by reference numerals P1a, P1b, P1c, and P1d, the flexible substrates 13a, 13b, 13c, and 13d are bent near the points where they connect to the spraying section 11 (near the pressing electrode 433). Furthermore, the pressing electrode 433 and the spraying section 11 are electrically connected to each other, for example, by using a thermoforming ACF (Anisotropic Conductive Film).

[0064] Actuating devices 41 are individually mounted on such flexible substrates 13a, 13b, 13c, and 13d (see reference). Figure 3These driving devices 41 are devices that output driving signals Sd (driving voltage Vd) for ejecting ink 9 from the nozzle orifices Hn in the corresponding nozzle rows of the ejection section 11. Therefore, such driving signals Sd are output to the ejection section 11 from each of the flexible substrates 13a, 13b, 13c, and 13d. Furthermore, each of these driving devices 41 is, for example, constructed from an ASIC (Application Specific Integrated Circuit).

[0065] Furthermore, these driving components 41 are cooled by the aforementioned cooling units 141 and 142. Specifically, as... Figure 3 As shown, cooling units 141 are fixedly arranged between each other on the driving devices 41 on the flexible substrates 13a and 13b. These cooling units 141 are pressed against each other to cool each driving device 41. Similarly, cooling units 142 are fixedly arranged between each other on the driving devices 41 on the flexible substrates 13c and 13d. These cooling units 142 are pressed against each other to cool each driving device 41. Furthermore, these cooling units 141 and 142 can be constructed using various cooling mechanisms.

[0066] [Detailed structure of flexible substrates 13a, 13b, 13c, and 13d]

[0067] Next, besides Figures 1 to 3 In addition, refer to Figure 4A , Figure 4B , Figures 5 to 8 Detailed examples of the aforementioned flexible substrates 13a, 13b, 13c, and 13d will be described.

[0068] Figure 4A , Figure 4B A schematic diagram is shown in the Z-X plan view. Figure 2 , Figure 3 Detailed structural examples of the flexible substrates 13a to 13d shown. Specifically, respectively Figure 4A Examples of planar configurations (Z-X planar configuration examples) of flexible substrates 13a and 13c are shown. Figure 4B Examples of planar configurations (Z-X planar configuration examples) of flexible substrates 13b and 13d are shown. Additionally, Figure 5 A schematic diagram is shown in the Z-X plan view. Figure 4B The example shown illustrates the configuration of the wiring, etc., within the flexible substrates 13b and 13d. Figure 6 , Figure 7 The diagrams are illustrated schematically using plan views (Z-X plan view). Figure 5 Detailed configuration examples of each wiring shown (configuration examples illustrated from the surface S1 side, as described later). Figure 8 A schematic diagram is shown using a cross-sectional view (X-Y cross-sectional view). Figure 6 , Figure 7 The configuration example shown. Furthermore, in Figures 5 to 8 Flexible substrates 13b and 13d are collectively referred to as flexible substrate 13 and are shown in the diagram. Furthermore, in these... Figures 5 to 8 Although examples of configurations for flexible substrates 13b and 13d are shown, the configurations for flexible substrates 13a and 13c described above are essentially the same. Furthermore, in Figure 8 In the diagram, the first differential line Lt1, the second differential line Lt2, and the third differential lines Lt31 to Lt34 are collectively referred to as differential lines Lt and shown. The following explanation will use differential lines Lt as appropriate.

[0069] First, respectively as Figure 4A , Figure 4B and Figure 5 As shown, each of these flexible substrates 13a to 13d is provided with the following components: a connecting electrode 130, a first input terminal Tin1, a second input terminal Tin2, a first differential line Lt1, a second differential line Lt2, third differential lines Lt31 to Lt34, a plurality of (five in this example) driving devices 41, and the aforementioned crimping electrode 433.

[0070] The connecting electrode 130 is disposed in the end region on one side of the I / F substrate 12 of each flexible substrate 13a to 13d, and is used to electrically connect each flexible substrate 13a to 13d with the I / F substrate 12.

[0071] The first input terminal Tin1 and the second input terminal Tin2 respectively input the transmission data Dt (the aforementioned printing control signal Sc) transmitted from the outside of the inkjet head 1 (the aforementioned printing control unit 2) (see reference). Figure 1 , Figure 2 , Figure 4A , Figure 4B and Figure 5 Furthermore, this transmitted data Dt is transmitted to each flexible substrate 13a-13d via one of the first input terminals Tin1 and the second input terminal Tin2. Specifically, for example, as... Figure 4A As shown, in the flexible substrates 13a and 13c, the transmission data Dt is transmitted to each flexible substrate 13a and 13c via the first input terminal Tin1. On the other hand, for example, as... Figure 4B and Figure 5 As shown, in the flexible substrates 13b and 13d, the transmission data Dt is transmitted to each flexible substrate 13b and 13d via the second input terminal Tin2.

[0072] exist Figure 4A , Figure 4B and Figure 5 In the example shown, the five actuators 41 described above are respectively mounted on each flexible substrate 13a to 13d (on one side of surface S1, either surface S1 or back surface S2). As such five actuators 41, in Figure 4A , Figure 4B and Figure 5 In the example shown, the following are provided: one first driver 411; one second driver 415; and three third drivers 412 to 414. Furthermore, these five drivers 41 are connected in series (cascaded) on the surface S1 via multiple differential lines described later, between the first input terminal Tin1 and the second input terminal Tin2. Specifically, as... Figure 4A , Figure 4B and Figure 5 As shown, each of the flexible substrates 13a to 13d is connected in series from the first input terminal Tin1 side to the second input terminal Tin2 side in the order of first driver 411, third driver 412 to 414, and second driver 415. In other words, the first driver 411 is located at one end of this series configuration of driver 41s, and the second driver 415 is located at the other end of the series configuration. Moreover, a plurality of (three in this example) third driver 412 to 414 are located between these first driver 411s and second driver 415s. As described above, these five driver 41s generate the aforementioned drive signal Sd based on the transmission data Dt input via one of the input terminals Tin1 and Tin2. Furthermore, the drive signal Sd generated in this way is supplied to the ejection section 11 side via the aforementioned press-fit electrode 433 on each of the flexible substrates 13a to 13d.

[0073] Furthermore, multiple transmission lines (differential lines) are configured between the first input terminal Tin1 and the second input terminal Tin2 for transmitting transmission data Dt via five driver devices 41 arranged in series. In other words, these differential lines are lines used to transmit transmission data Dt as differential signals to each driver device 41. Specifically, as follows... Figure 4A , Figure 4B and Figure 5As shown, a first differential line Lt1 is arranged between the first input terminal Tin1 and the first driver 411, and a second differential line Lt2 is arranged between the second input terminal Tin2 and the second driver 415. Additionally, a third differential line Lt31 is arranged between the first driver 411 and the third driver 412, and a third differential line Lt32 is arranged between the third driver 412 and the third driver 413. A third differential line Lt33 is arranged between the third driver 413 and the third driver 414, and a third differential line Lt34 is arranged between the third driver 414 and the second driver 415.

[0074] Here, as described above, the input terminals (first input terminal Tin1 or second input terminal Tin2) for inputting transmission data Dt in flexible substrates 13a, 13c and 13b, 13d are different from each other (see reference). Figure 4A , Figure 4B and Figure 5 Furthermore, the transmission directions of the data Dt input into the flexible substrates 13a, 13c and 13b, 13d are different within the substrates. That is, the transmission data Dt input from the first input terminal Tin1 in the flexible substrates 13a and 13c are transmitted in the order of the first driver device 411, the third driver devices 412, 413, 414 and the second driver device 415 (see reference). Figure 4A On the other hand, the transmission data Dt input from the second input terminal Tin2 in the flexible substrates 13b and 13d is transmitted in the order of the second driver device 415, the third driver devices 414, 413, 412 and the first driver device 411 (see reference). Figure 4B and Figure 5 ).

[0075] Thus, the input terminals for transmitting data Dt and the transmission direction of data Dt in flexible substrates 13a, 13c, 13b, and 13d are different from each other. However, the structures of the substrates in each of these flexible substrates 13a, 13c, 13b, and 13d are identical, and the configuration of each flexible substrate 13a to 13d is common (shared) (see reference). Figure 4A , Figure 4B and Figure 5 That is, there is no need to prepare multiple flexible substrates (driving substrates) according to the transmission direction of the transmitted data Dt, and only one type of flexible substrate (driving substrate) is set in the inkjet head 1.

[0076] In addition, such as Figure 5As shown, a drive power line Ld for supplying drive power to each of the drive devices 41 (first drive device 411, third drive devices 412, 413, 414 and second drive device 415) is provided on the flexible substrate 13. Furthermore, a component placement area 40 for placing various components other than the drive devices 41 is provided on the flexible substrate 13 (back side S2).

[0077] Here, as Figures 6 to 8 As shown, the aforementioned drive power line Ld includes a first power supply line Wp1, a second power supply line Wp2, and a second digital ground line Wdg2, etc. Furthermore, in Figure 6 , Figure 7 In the planar configuration example of the flexible substrate 13 shown, Figure 6 The diagram shows an example of the configuration of the wiring near the second drive device 415. Figure 7 The diagram shows an example of the configuration of the wiring near the second drive device 415 and the third drive device 414.

[0078] In addition, such as Figure 8 As shown, the flexible substrate 13 of this embodiment is a double-sided substrate with a two-layer structure having the aforementioned surface S1 and back surface S2. That is, regarding this flexible substrate 13, as a wiring layer of such a two-layer structure, it has a first wiring layer W1 on the surface S1 side and a second wiring layer W2 on the back surface S2 side, which are opposite each other along a direction orthogonal to the substrate surface (Z-X plane) (Y-axis direction).

[0079] (Driver 41)

[0080] First, such as Figures 6 to 8 As shown, the aforementioned driving devices 41 (first driving device 411, third driving devices 412, 413, 414 and second driving device 415) are mounted on the first wiring layer W1 on the surface S1 side of the flexible substrate 13. Additionally, as... Figure 6 and Figure 7 As shown, each driving device 41 has a first input / output section Tio1, a second input / output section Tio2, a control terminal section Tc, a drive terminal section Td, and a power supply terminal section Tp.

[0081] For example, such as Figure 6 and Figure 7As shown, the aforementioned differential lines Lt (first differential line Lt1, second differential line Lt2, and third differential lines Lt31 to Lt34) are respectively connected to the first input / output section Tio1 and the second input / output section Tio2. Specifically, the first differential line Lt1 connects the first input terminal Tin1 to the first input / output section Tio1 in the first driver device 411. Furthermore, the second differential line Lt2 connects the second input terminal Tin2 to the second input / output section Tio2 in the second driver device 415 (see reference). Figure 6 and Figure 7 Additionally, four third differential lines Lt31 to Lt34 are connected via three third drivers 412 to 414 between the second input / output section Tio2 in the first driver 411 and the first input / output section Tio1 in the second driver 415. Specifically, the third differential line Lt31 connects the second input / output section Tio2 in the first driver 411 and the first input / output section Tio1 in the third driver 412. Furthermore, the third differential line Lt32 connects the second input / output section Tio2 in the third driver 412 and the first input / output section Tio1 in the third driver 413. The third differential line Lt33 connects the second input / output section Tio2 in the third driver 413 and the first input / output section Tio1 in the third driver 414 (see reference). Figure 7 The third differential line Lt34 connects the second input / output section Tio2 in the third drive device 414 and the first input / output section Tio1 in the second drive device 415 (see reference). Figure 6 and Figure 7 ).

[0082] The control terminal Tc is a terminal for electrically connecting the control wiring (wiring for various controls of the drive device 41) on the flexible substrate 13 to each drive device 41. The control terminal Tc extends along the long axis direction (X-axis direction) of each drive device 41 on the input side (along the positive direction of the Z-axis).

[0083] The drive terminal Td is a terminal for electrically connecting each drive device 41 to the signal wiring (hereinafter referred to as signal wiring Ws) for transmitting the drive signal Sd output from each drive device 41. The drive terminal Td extends along the long axis direction (X-axis direction) of each drive device 41 on the output side (along the negative direction of the Z-axis).

[0084] For example, such as Figure 6 and Figure 7As shown, the power supply terminal Tp extends along the long axis (X-axis direction) of each driver 41 in the region between the control terminal Tc and the drive terminal Td of each driver 41. Drive power is supplied to this power supply terminal Tp from the first power supply wiring Wp1 described later (see reference). Figure 6 and Figure 7 ).

[0085] (Differential circuit Lt)

[0086] like Figures 6 to 8 As shown, the aforementioned differential lines Lt (first differential line Lt1, second differential line Lt2, and third differential lines Lt31 to Lt34) are respectively disposed on the first wiring layer W1 on the surface S1 side of the flexible substrate 13. As mentioned earlier, each of these differential lines Lt is a line used to transmit transmission data Dt as a differential signal, and is constructed, for example, using LVDS (Low Voltage Differential Signaling). However, each differential line Lt can also be constructed using, for example, CML (Current Mode Logic) or ECL (Emitter Coupled Logic).

[0087] Furthermore, these differential lines Lt are constructed using, for example, so-called microstrip lines or coplanar lines. And, as will be described in detail later, the impedance control of each differential line Lt is performed such that the characteristic impedance of each differential line Lt is set to 100Ω. Moreover, the set value of this characteristic impedance is not limited to 100Ω as described above; it can also be set to other values ​​such as 150Ω. However, when the set value of this characteristic impedance is set to a value different from 100Ω or 150Ω, the power loss in each differential line Lt increases, and there are concerns that the accuracy of signal transmission may decrease.

[0088] Furthermore, various components (e.g., AC coupling capacitors needed when the common voltage differs between the output and input devices) or vias can be configured on each of these differential lines Lt. Additionally, when vias are configured, they can be placed near various power or ground wirings for impedance control.

[0089] (Power supply wiring Wp1, power supply wiring Wp2, digital grounding wiring Wdg2)

[0090] like Figures 6 to 8 As shown, the aforementioned first power supply wiring Wp1 is disposed on the first wiring layer W1 on the surface S1 side of the flexible substrate 13. For example, as... Figure 6 and Figure 7As shown, the first power supply wiring Wp1 is a wiring for supplying drive power (power potential) to each drive device 41 via the aforementioned power supply terminal Tp.

[0091] like Figures 6 to 8 As shown, the aforementioned second power supply wiring Wp2 is disposed on the second wiring layer W2 on the back side S2 side of the flexible substrate 13 (in Figure 6 and Figure 7 (These are indicated by dashed lines). For example, as shown in the image. Figures 6 to 8 As shown, the second power supply wiring Wp2 is electrically connected to the first power supply wiring Wp1 via the first through-hole TH1. Additionally, for example, as... Figure 6 and Figure 7 As shown, the second power supply wiring Wp2 extends on the second wiring layer W2 from near both ends (near the first input / output section Tio1 and the second input / output section Tio2) along the positive Z-axis direction in the direction of the long axis (X-axis direction) of each driving device 41. Furthermore, for example, as... Figure 6 and Figure 7 As shown, the second power supply wiring Wp2 is configured to be opposite (overlapping) a portion of the differential line Lt (the first region A1 described later).

[0092] For example, such as Figure 6 , Figure 7 As shown by the dashed line, the aforementioned second digital ground wiring Wdg2 is disposed on the second wiring layer W2 on the back side S2 of the flexible substrate 13. Specifically, for example, as... Figure 6 and Figure 7 As shown, the second digital grounding wiring Wdg2 is disposed on the second wiring layer W2 on the input side (positive Z-axis side) of the control terminal section Tc of each driver device 41. This second digital grounding wiring Wdg2 functions as a digital grounding wiring among the various control signals (digital signals) input to the aforementioned control terminal section Tc of each driver device 41. Furthermore, for example, as... Figure 6 and Figure 7 As shown, the second digital grounding wiring Wdg2 is configured to be opposite (overlapping) a portion of the differential line Lt (the third region) mentioned above.

[0093] Here, for example, such as Figure 6As shown, the second differential line Lt2 is arranged opposite to the second power supply line Wp2 along its extension direction (Z-axis direction), and then opposite to the second digital ground line Wdg2, and connected to the second input / output section Tio2 of the second driver device 415. Similarly, the first differential line Lt1 is arranged opposite to the second power supply line Wp2 along its extension direction (Z-axis direction), and then opposite to the second digital ground line Wdg2, and connected to the first input / output section Tio1 of the first driver device 411. Additionally, for example, as... Figure 6 and Figure 7 As shown, each differential line Lt is configured along the X-axis in a manner orthogonal to the boundary lines (lines along the Z-axis) of these lines near the boundary of the second power supply wiring Wp2 and the second digital ground wiring Wdg2. Furthermore, near such boundaries, for example, as... Figure 6 and Figure 7 As shown, because the capacitance value assigned to the second power supply wiring Wp2 in the gap region between the second power supply wiring Wp2 and the second digital ground wiring Wdg2 decreases, the characteristic impedance of each differential line Lt changes. To minimize this change in characteristic impedance, as described above, it is desirable to arrange each differential line Lt orthogonally to the boundary lines of these wirings, or to minimize the width of the aforementioned gap region. Furthermore, the width of this gap region can be exemplified by a value of approximately 10 (μm / V), for example, when the potential difference between the second power supply wiring Wp2 and the second digital ground wiring Wdg2 is 30V or less. That is, when the potential difference is 25V, a gap region width of 0.25mm or more is preferable.

[0094] (Regarding the relationship between wiring width and line width)

[0095] Here, in the flexible substrate 13 of this embodiment, for example, as Figure 6 and Figure 7 As shown, the wiring width dp2 of the second power supply wiring Wp2 is greater than the wiring width dL1 of the aforementioned first region A1 (the region opposite to the second power supply wiring Wp2) of the differential line Lt (dp2 > dL1). Additionally, for example, as... Figure 6 and Figure 7 As shown, the wiring width ddg2 of the second digital grounding wiring Wdg2 is greater than the wiring width dL3 of the aforementioned third region of the differential line Lt (the region opposite to the second digital grounding wiring Wdg2) (ddg2 > dL3).

[0096] Furthermore, the width directions of the wiring widths dp2, ddg2, and line widths dL1, dL3 mentioned here refer to the width directions based on the extension direction of each differential line Lt. The width directions also vary depending on the extension direction of each differential line (in...). Figure 6 and Figure 7 In the example, the Z-axis direction (or X-axis direction) changes. Incidentally, in Figure 6 and Figure 7 In the example, regarding line widths dL1 and dL3, various cases of these multiple extension directions are illustrated. On the other hand, in Figure 6 and Figure 7 In the examples provided, for simplicity, only one of these multiple extension directions is illustrated for the wiring widths dp2 and ddg2. Furthermore, the meanings of these width directions include the variations described later, and the same applies below.

[0097] Thus, for example, the width of the second power supply wiring Wp2 or the second digital ground wiring Wdg2 is set to be relatively wide. Specifically, if these wiring widths are set narrower, the inductive component on the differential line Lt will increase, raising concerns that the quality of the transmitted signal may deteriorate due to the increased characteristic impedance. Furthermore, if the width of these power supply wirings themselves decreases, the wiring resistance increases, further increasing the inductive component of the power supply wiring, potentially making it difficult to provide a stable power supply and leading to performance degradation. Incidentally, to impart a stable characteristic impedance to the differential line Lt, the values ​​of the aforementioned wiring widths dp2 and ddg2 can be, as an example, more than three times the aforementioned line widths dL1 and dL3 (dp2 ≥ (3 × dL1), ddg2 ≥ (3 × dL3)).

[0098] Here, the aforementioned flexible substrates 13, 13a-13d each correspond to a specific example of the "driving substrate" in this disclosure. Furthermore, surface S1 and the first wiring layer W1 each correspond to a specific example of the "first wiring layer" in this disclosure, and back surface S2 and the second wiring layer W2 each correspond to a specific example of the "second wiring layer" in this disclosure. Additionally, the first input terminal Tin1 and the second input terminal Tin2 each correspond to a specific example of the "first input terminal" and "second input terminal" in this disclosure. Furthermore, the transmitted data Dt (printing control signal Sc) corresponds to a specific example of the "differential signal" in this disclosure. Furthermore, the first differential line Lt1, the second differential line Lt2, and the third differential lines Lt31-Lt34 each correspond to a specific example of the "differential line" in this disclosure.

[0099] [Actions and their functions / effects]

[0100] (A. Basic Operations of Printer 5)

[0101] In this printer 5, the ink 9 is ejected using the inkjet head 1 as described below to perform a recording operation (printing operation) on the recorded medium (recording paper P, etc.). Specifically, in the inkjet head 1 of this embodiment, the ink 9 is ejected using a cut (share) mode as described below.

[0102] First, the actuators 41 on each of the flexible substrates 13a, 13b, 13c, and 13d apply a driving voltage Vd (driving signal Sd) to the aforementioned driving electrodes (common electrode and active electrode) within the actuator plate 111 in the ejection section 11. Specifically, each actuator 41 applies the driving voltage Vd to each driving electrode disposed on a pair of driving walls that divide the aforementioned ejection channel. As a result, these pairs of driving walls deform in a manner that protrudes toward the pseudo-channel side adjacent to their ejection channel.

[0103] At this point, the drive wall bends and deforms in a V-shape, centered on the middle position along its depth direction. Furthermore, this bending deformation of the drive wall causes the ejection channel to expand. Thus, the bending deformation caused by the piezoelectric thickness slip effect on the pair of drive walls increases the volume of the ejection channel. Moreover, because the volume of the ejection channel increases, ink 9 is induced into the ejection channel.

[0104] Next, the ink 9 thus induced into the ejection channel becomes a pressure wave and propagates inside the ejection channel. Moreover, at the timing (or near the timing) when this pressure wave reaches the nozzle orifice Hn of the nozzle plate 112, the driving voltage Vd applied to the driving electrode becomes 0 (zero) V. As a result, as the driving wall recovers from the aforementioned bent deformation state, the temporarily increased volume of the ejection channel returns to its original state.

[0105] Thus, as the volume of the ejection channel returns to its initial state, the pressure inside the ejection channel increases, pressurizing the ink 9 within it. As a result, droplets of ink 9 are ejected outwards (towards the recording paper P) through the nozzle orifice Hn (see reference). Figure 1 This ejects ink 9 from the inkjet head 1, resulting in the recording of images or characters on the recording paper P.

[0106] (B. Function / Effect of inkjet head 1)

[0107] Next, referring to the existing general transmission line configuration example ( Figure 9A , Figure 9B The functions and effects of the inkjet head 1 in this embodiment will be explained in detail.

[0108] (B-1. Example of the structure of a general transmission line)

[0109] Firstly, flexible substrates containing driving components are frequently used inside inkjet printers. This is because using flexible substrates increases the flexibility in wiring configuration compared to rigid substrates (non-flexible substrates), and allows for miniaturization of the printhead. However, flexible substrates with more wiring layers are generally more expensive than rigid substrates, so from the perspective of printhead manufacturing costs, it is best to avoid their use. Therefore, various methods have been proposed that design the layout of various wiring or components within the flexible substrate while maintaining printhead performance and manufacturing yield.

[0110] Furthermore, in recent years, due to the need to increase printing speeds to improve productivity, or the increase in data volume caused by the increase in the number of nozzles in the inkjet head, high-speed differential transmission has been widely adopted, such as in LVDS or CML as mentioned above. Therefore, it is important to effectively arrange differential lines (high-speed differential lines) within the limited space of the inkjet head. In this case, impedance control, as mentioned above, can be cited as a method for efficiently transmitting high-speed differential signals.

[0111] Impedance control refers to a method of preventing electrical reflections on transmission lines and enabling the transmission of high-frequency signals by controlling the characteristic impedance of the transmission line. Specifically, the characteristic impedance of the transmission line is set to a desired value by adjusting factors such as the width or thickness of the transmission line, the distance between the transmission line and the inner layers surrounding it, and the dielectric constant of the dielectric material surrounding the transmission line. The characteristic impedance is typically set to 50Ω, but in the case of the differential circuit described above, the characteristic impedance between a pair of lines is set to 100Ω.

[0112] In this case, it is usually necessary to set the number of wiring layers on the substrate to two or more. This is to provide appropriate capacitance to the transmission lines that are the objects of impedance control.

[0113] Figure 9A and Figure 9B Examples of typical transmission line configurations are illustrated using cross-sectional diagrams. Specifically, Figure 9A The transmission line shown is a so-called microstrip line. Figure 9B The transmission line shown is a so-called coplanar line.

[0114] First of all, Figure 9A In the transmission line shown, a line (differential line Lt101) is arranged on the first layer (surface) of the two-layer double-sided substrate (driving substrate 103), and a grounding line Wg102 is arranged on the second layer (back side). Additionally, in Figure 9B In the transmission line shown, with Figure 9ASimilarly, in the case of a two-layer double-sided substrate (driving substrate 203), a line (differential line Lt201) is arranged on the first layer (surface), and a grounding line Wg202 is arranged on the second layer (back side). Furthermore, in this… Figure 9B In the transmission line, other grounding wiring Wg201 is configured on both sides of the differential line Lt201 in the first layer.

[0115] In this configuration Figure 9A , Figure 9B In the transmission lines, the substrate materials located between the first and second layers function as dielectrics (dielectric layers 100 and 200) and impart capacitance (capacitors C100 and C200) to each line (differential lines Lt101 and Lt201). Furthermore, particularly... Figure 9B In the transmission line, the other grounding wiring Wg201 on both sides of the differential line Lt201 will be further given capacitance C201.

[0116] In addition, such as Figure 9A and Figure 9B The configuration of the transmission line (differential line) shown, within a narrow substrate, significantly limits various wiring configurations. Furthermore, due to these limitations on wiring configuration, for example, when the power supply wiring width is set narrow, the power supply performance to the driving devices deteriorates, and the ink ejection performance of the inkjet head also decreases. In contrast, in conventional single-ended transmissions using lower signal frequencies in inkjet heads, impedance control is not performed, and therefore, such limitations on wiring configuration do not exist.

[0117] Furthermore, due to the aforementioned limitations on wiring configuration, when impedance control is performed in a differential circuit, it is generally desirable for the number of wiring layers on the driver substrate to be at least three. Specifically, the ideal layer configuration on such a driver substrate is as follows.

[0118] • Layer 1: Wiring layer (mainly contains signal wiring related to the control of the driving devices, and also contains some power wiring for the driving devices)

[0119] • Layer 2: Grounding layer (mainly containing grounding wiring for driving devices)

[0120] • Layer 3: Power layer (mainly contains power cabling for driving devices, and also contains some signal cabling for driving devices)

[0121] In this three-layer configuration, for example, signal wiring (differential lines) for transmitting digital data for printing can be configured on the first or third layer, and impedance control can be achieved through the ground wiring on the second layer to accommodate high-speed differential transmission. Furthermore, in the third power layer, high-quality power wiring with a wider width can be used to correspond to the power supply pattern to the driving devices. Therefore, this three-layer configuration improves the power supply performance to the driving devices and also enhances the ink ejection performance from the inkjet head.

[0122] However, manufacturing costs increase with such a three-layer substrate structure. That is, while increasing the number of substrate layers for impedance control improves the inkjet head's output performance, it also increases manufacturing costs.

[0123] Thus, in the existing general transmission line configuration, it is difficult to simultaneously improve ink ejection performance and reduce manufacturing costs when using a drive substrate suitable for inkjet heads.

[0124] (B-2. Function / Effect)

[0125] In contrast, the flexible substrate 13 (13a to 13d) of the inkjet head 1 in this embodiment has the following configuration, and therefore, for example, the following effects and functions can be obtained.

[0126] That is, firstly, in the flexible substrate 13, the wiring width dp2 of the second power wiring Wp2 of the second wiring layer W2, which is arranged opposite to the first region A1 of the differential line Lt in the first wiring layer W1, is greater than the line width dL1 of the first region A1 in the differential line Lt (dp2 > dL1).

[0127] Therefore, the second power supply wiring Wp2 functions as an inner layer for the additional capacitor of the differential line Lt, and the impedance control of the differential line Lt is performed by the second power supply wiring Wp2. Thus, for example, compared to the case where the ground wiring in the second wiring layer W2 (e.g., the aforementioned second digital ground wiring Wdg2) is used as the aforementioned inner layer for impedance control (comparative example), the following will occur: That is, the wiring width dp2 of the second power supply wiring Wp2 can be widened, improving the power supply performance to each driving device 41.

[0128] Furthermore, unlike the comparative examples described above, in this embodiment, it is not necessary to use the ground wiring in the second wiring layer W2 as an inner layer. Therefore, compared to the comparative examples described above, the wiring pattern of such ground wiring can be reduced. Thus, even if the wiring layer of the flexible substrate 13 (13a to 13d) is constructed as a two-layer structure (first wiring layer W1 and second wiring layer W2), the degree of freedom in wiring arrangement can be ensured. Therefore, unlike the existing cases described above, it is not necessary to set the wiring layer to three or more layers.

[0129] In summary, in this embodiment, the ink 9 ejection performance using the drive signal Sd output from the drive device 41 can be improved, while the manufacturing cost of the flexible substrate 13 or the inkjet head 1 can be reduced.

[0130] Furthermore, in this embodiment, even when multiple driver devices 41 are connected in series (cascaded) between the first input terminal Tin1 and the second input terminal Tin2 via multiple differential lines Lt, the following applies: That is, as described above, impedance control of each differential line Lt is possible. That is, as described above, by ensuring the power supply performance of the drive power supply to each driver device 41, deviations in the ink output performance caused by the drive signal Sd output from each driver device 41 can be suppressed.

[0131] Furthermore, in this embodiment, the aforementioned driving substrate is constructed using a flexible substrate 13 (13a to 13d). Therefore, as described above, even with a two-layer wiring structure, the freedom of wiring configuration can be ensured, thereby further increasing the cost reduction effect. In other words, generally speaking, compared to a non-flexible substrate (rigid substrate), a flexible substrate tends to have higher manufacturing costs due to the increased number of wiring layers. Therefore, it can be said that a two-layer wiring structure can also ensure the freedom of wiring configuration, thereby further increasing the cost reduction effect.

[0132] <2. Variations>

[0133] Next, variations of the above-described embodiments (variations 1 and 2) will be described. Furthermore, the same reference numerals will be used for the same components as those in the embodiments, and descriptions will be omitted as appropriate.

[0134] [Variation Example 1]

[0135] (constitute)

[0136] Figure 10 and Figure 11 The arrangement of wiring and other components within the flexible substrate 13A of the liquid jet head (inkjet head) in Modified Example 1 is schematically shown in plan view (Z-X plan view) (the configuration example shown from the aforementioned surface S1 side). Furthermore, compared with the embodiments described... Figure 6 and Figure 7 Similarly, in Figure 10 The diagram shows an example of the configuration of the wiring near the second drive device 415. Figure 11 The diagram shows an example of the configuration of the wiring near the second drive device 415 and the third drive device 414.

[0137] Here, the printer equipped with the inkjet head described in Modification 1 corresponds to a specific example of the "liquid jet recording apparatus" in this disclosure. Furthermore, the aforementioned flexible substrate 13A corresponds to a specific example of the "drive substrate" in this disclosure.

[0138] like Figure 10 and Figure 11 As shown, the flexible substrate 13A of this modified example 1 corresponds to the flexible substrate 13 in the embodiment (see reference 13). Figure 6 and Figure 7 The first grounding wiring Wg1 and the second grounding wiring Wg2 were further set up, and the other components were basically the same.

[0139] like Figure 10 and Figure 11 As shown, the first grounding wiring Wg1 is disposed on the first wiring layer W1 on the surface S1 side of the flexible substrate 13A. The first grounding wiring Wg1 is a wiring for supplying driving power (ground potential) to each driving device 41 via the aforementioned power terminal portion Tp.

[0140] like Figure 10 , Figure 11 As shown by dashed lines, the second ground wiring Wg2 is disposed on the second wiring layer W2 on the back side S2 side of the flexible substrate 13A. For example, as... Figure 10 and Figure 11 As shown, the second grounding wiring Wg2 is electrically connected to the first grounding wiring Wg1 via the second through-hole TH2. Additionally, for example, as... Figure 10 and Figure 11 As shown, the second power supply wiring Wp2 is located between the second ground wiring Wg2 and the second digital ground wiring Wdg2, and the second ground wiring Wg2 extends along the Z-axis direction on the second wiring layer W2. Furthermore, for example, as... Figure 10 and Figure 11 As shown, the second grounding wiring Wg2 is configured to be opposite (overlapping) a portion of the differential line Lt (the second region A2 described later).

[0141] Here, in the flexible substrate 13A of Modified Example 1, for example, as Figure 10 and Figure 11 As shown, the wiring width dg2 of the second grounding wiring Wg2 is greater than the line width dL2 of the second region A2 (the region opposite to the second grounding wiring Wg2) in the differential line Lt (dg2 > dL2). Furthermore, the meaning of the width direction of these wiring widths dg2 and line widths dL2 is the same as in the aforementioned embodiment.

[0142] (Function / Effect)

[0143] Thus, in the flexible substrate 13A of Modified Example 1, the wiring width dg2 of the second ground wiring Wg2 is greater than the wiring width dL2 of the second region A2 in the differential line Lt (dg2 > dL2). Therefore, in addition to the second power wiring Wp2 described in the embodiment, the second ground wiring Wg2 also functions as the aforementioned inner layer, and impedance control of the differential line Lt is also performed through the second power wiring Wp2 and the second ground wiring Wg2.

[0144] Therefore, in this modified example 1, the wiring width dg2 of the second ground wiring Wg2 can also be widened, further improving the power supply performance to each driving device 41. Furthermore, even when multiple driving potentials are supplied to each driving device 41, as described above, the two-layer structure of the wiring layer of the flexible substrate 13A ensures flexibility in wiring configuration. As a result, in this modified example 1, compared to the embodiment, the ink ejection performance of the ink 9 can be further improved, and the manufacturing cost of the flexible substrate 13A or the inkjet head can be further reduced.

[0145] [Variation Example 2]

[0146] (constitute)

[0147] Figure 12 A schematic plan view (Z-X plan view) illustrates an example of the configuration of wiring, etc., within the flexible substrate 13B of the liquid jet head (inkjet head) involved in Modified Example 2 (the configuration example shown from the aforementioned surface S1 side). Furthermore, similar to the aforementioned... Figure 6 and Figure 10 Similarly, in Figure 12 The diagram shows an example of the configuration of the wiring near the second drive device 415. Additionally, Figure 13 A schematic diagram is shown in the form of a plan view (Z-X plan view). Figure 12 Detailed configuration examples in a portion of the area shown (near the area indicated by labels P2a and P2b) (configuration examples shown from the surface S1 side).

[0148] Here, the printer equipped with the inkjet head described in Modification 2 corresponds to a specific example of the "liquid jet recording apparatus" in this disclosure. Furthermore, the aforementioned flexible substrate 13B corresponds to a specific example of the "drive substrate" in this disclosure.

[0149] like Figure 12 As shown, the flexible substrate 13B of this modified example 2 corresponds to the flexible substrate 13A of modified example 1 (see reference). Figure 10 and Figure 11 The drive capacitor Cd and the return wiring Wr, which includes the return path described later, are further configured, and the other configurations are basically the same.

[0150] For example, such as Figure 12 As shown by the dashed line, the driving capacitor Cd is disposed on the second wiring layer W2 on the back side S2 of the flexible substrate 13B. Figure 5 (Within the component configuration area 40 shown). Specifically, for example, as Figure 12 As shown, the driving capacitor Cd is disposed on the input side of each driving device 41 on the second wiring layer W2 (on the positive Z-axis side relative to the aforementioned second digital ground wiring Wdg2). Additionally, for example, as... Figure 12 As shown, one end of the driving capacitor Cd is electrically connected to the second power supply wiring Wp2, and the other end of the driving capacitor Cd is electrically connected to the second ground wiring Wg2.

[0151] For example, such a drive capacitor Cd is provided for the following reasons: In order to simultaneously drive multiple nozzle holes Hn to discharge using the drive signal Sd, a capacitor element is needed to handle the instantaneous current consumption; therefore, such a drive capacitor Cd is placed in the power supply path. Furthermore, since the current is generated in a pulsed manner at this time, it is preferable to place the drive capacitor Cd, which is used to compensate for such pulsed current, near each drive device 41. Therefore, in this modified example 2, as described above, the drive capacitor Cd is placed near each drive device 41.

[0152] For example, such as Figure 12 As shown by dashed lines, the aforementioned return wiring Wr is disposed on the second wiring layer W2 on the back side S2 of the flexible substrate 13B. Specifically, for example, as... Figure 12 As shown, the return wiring Wr has a wiring opposition area Aws2 on the output side of each driver device 41 on the second wiring layer W2. This wiring opposition area Aws2 is configured to oppose the wiring area Aws1 on the first wiring layer W1, which contains the signal wiring Ws for transmitting the drive signal Sd. Additionally, for example, as... Figure 12 As shown, the return wiring Wr becomes electrically connected to the second ground wiring Wg2 in the second wiring layer W2.

[0153] As explained below, such return wiring Wr contains a path (return path) for the current in the drive signal Sd to return to the drive capacitor Cd. This return path includes, for example... Figure 12The first return path Pr1 and the second return path Pr2 are shown. The first return path Pr1 is the path from the aforementioned wiring opposition area Aws2 through one end of the driver device 41 to the driving capacitor Cd. The second return path Pr2 is the path from the wiring opposition area Aws2 through the other end of the driver device 41 to the driving capacitor Cd. Furthermore, it is preferable that the inductance value L and the resistance value R on each of these two return paths (the first return path Pr1 and the second return path Pr2) are approximately equal. This is because it further suppresses the generation of noise (noise caused by the return paths) described later.

[0154] Here, for example, such as Figure 13 As shown, preferably, the flexible substrate 13B is labeled with P2a and P2b (refer to...). Figure 12 Near the first wiring layer W1, a pair of first digital grounding wires Wdg1 are further configured as follows. This pair of first digital grounding wires Wdg1 is configured on both sides of the first wiring layer W1 along the width direction (Z-axis direction) of the differential line Lt. Furthermore, this pair of first digital grounding wires Wdg1 are respectively connected via, for example... Figure 13 The third through-hole TH3 shown is electrically connected to the aforementioned second digital grounding wiring Wdg2.

[0155] Additionally, for example, such as Figure 13 As shown, preferably, a protrusion Pj is provided in the region opposite the gap region Ag on the second wiring layer W2 (on the first wiring layer W1) as follows. For example, as Figure 13 As shown, the aforementioned gap region Ag is located between the opposite region of the first region A1 of the second power supply wiring Wp2 relative to the differential line Lt and the opposite region of the second ground wiring Wg2 relative to the second region A2 of the differential line Lt. Additionally, the aforementioned protrusion Pj is a portion protruding from at least one of the pair of first digital ground wirings Wdg1 toward the differential line Lt side. Furthermore, in Figure 13 In the example shown, such a protrusion Pj is provided on both sides of this pair of first digital grounding wires Wdg1, but it is not limited to this example. That is, for example, such a protrusion Pj may be provided on only one of this pair of first digital grounding wires Wdg1.

[0156] (Function / Effect)

[0157] Thus, in the flexible substrate 13A of Modified Example 2, there is a wiring opposition region Aws2 opposite to the aforementioned wiring region Aws1, and the return wiring Wr containing the aforementioned return path is connected to the second ground wiring Wg2 in the second wiring layer W2.

[0158] Therefore, such a return path is easily connected to the drive capacitor Cd, and the electrical conduction state between the drive capacitor Cd, which is the final location of the return path, and the return wiring Wr is good (achieving a low-impedance electrical connection). As a result, in this modified example 2, the generation of noise caused by such a return path can be suppressed, and the ink output performance of the ink 9 can be further improved compared with the embodiment and the modified example 1.

[0159] Furthermore, in this modified example 2, the aforementioned return wiring Wr includes both the first return path Pr1 and the second return path Pr2, so it is distributed via both ends (one end and the other end) of each driving device 41 as follows. That is, since the loop of the current return path is reduced, the generation of noise from the return path can be suppressed. As a result, the ink output performance of the ink 9 can be further improved.

[0160] Furthermore, in this modified example 2, by respectively providing the first digital grounding wiring Wdg1 and the second digital grounding wiring Wdg2 configured as described above, impedance control of the differential line Lt can be easily performed. Specifically, for example, even if the capacitance between the second power supply wiring Wp2 or the second grounding wiring Wg2 and the differential line Lt is insufficient, a capacitor is added through a pair of first digital grounding wiring Wdg1, thus making impedance control of the differential line Lt easy. As a result, the transmission quality of the differential signal (transmission data Dt) transmitted on the differential line Lt can be improved, and since the differential signal can be transmitted at a higher speed, high-speed printing by the inkjet head can be achieved.

[0161] Furthermore, in this modified example 2, at least one of the pair of first digital ground wires Wdg1 in the first wiring layer W1 is provided with a protrusion Pj, thereby avoiding insufficient capacitance between the differential line Lt caused by the gap region Ag in the second wiring layer W2 (the inner non-configured area between the second power wire Wp2 and the second ground wire Wg2). As a result, the transmission quality of the differential signal (transmitted data Dt) can be further improved, and since the differential signal can be transmitted at a higher speed, even higher speed printing by the inkjet head can be achieved.

[0162] <3. Other variations>

[0163] While some embodiments and variations have been described above to illustrate this disclosure, this disclosure is not limited to these embodiments and various variations are possible.

[0164] For example, in the above embodiments, specific examples of the configuration (shape, arrangement, number, etc.) of each component in the printer 5 and the inkjet head 1 have been described, but the configuration is not limited to that described in the above embodiments, and may be other shapes, arrangements, numbers, etc.

[0165] Specifically, for example, in the above embodiments, examples of configurations such as flexible substrates (driving substrates), driving devices, differential lines, and various wirings have been described. However, these configurations are not limited to those described in the above embodiments. For example, in the above embodiments, the case where the "driving substrate" in this disclosure is a flexible substrate has been illustrated, but the "driving substrate" in this disclosure may also be a non-flexible substrate. Furthermore, in the above embodiments, an example of multiple driving substrates being disposed within the inkjet head has been described, but this is not limited to this example; for example, only one driving substrate may be disposed within the inkjet head. Furthermore, in the above embodiments, an example of multiple driving devices being disposed within each driving substrate (arranged in series with each other) has been described, but this is not limited to this example; for example, only one driving device may be disposed within each driving substrate.

[0166] Furthermore, the numerical examples of the various parameters described in the above embodiments are not limited to the numerical examples described in the embodiments, etc., and may be other values.

[0167] Furthermore, the inkjet head structure can accommodate various types of inkjet heads. For example, it can be a side-jet type inkjet head that ejects ink 9 from the center of each ejection channel in the extending direction of the actuator plate 111. Alternatively, it can be an edge-jet type inkjet head that ejects ink 9 along the extending direction of each ejection channel. Moreover, the printer configuration is not limited to the embodiments described above; various configurations, such as MEMS (Micro Electro Mechanical Systems), can be applied.

[0168] Furthermore, this disclosure applies to either a recirculating inkjet head that uses ink 9 to circulate between the ink tank and the inkjet head, or a non-recirculating inkjet head that does not use ink 9 to circulate.

[0169] Furthermore, the series of processes described in the above embodiments can be performed using either hardware (circuit) or software (program). In the case of software implementation, the software consists of a group of programs used to instruct the computer to perform various functions. Each program can be pre-loaded into the computer for use, or it can be installed onto the computer from a network or recording medium.

[0170] Furthermore, in the above embodiments, a printer 5 (inkjet printer) has been described as a specific example of the "liquid jet recording apparatus" in this disclosure. However, this is not a limitation, and this disclosure can also be applied to other devices besides inkjet printers. In other words, the "liquid jet head" (inkjet head) of this disclosure can also be applied to other devices besides inkjet printers. Specifically, for example, the "liquid jet head" of this disclosure can also be applied to devices such as fax machines or on-demand printing machines.

[0171] Furthermore, the various examples described so far can be combined in any way and applied.

[0172] Furthermore, the effects described in this specification are merely illustrative and not limited to them; other effects may also be possible.

[0173] Alternatively, this disclosure may also take the following form.

[0174] (1) A drive board, adapted for a liquid jet head having a jetting section for jetting liquid and outputting a drive signal for jetting liquid to the jetting section, comprising:

[0175] The first wiring layer and the second wiring layer are positioned opposite each other along a direction orthogonal to the substrate surface;

[0176] One or more driving devices are mounted on the first wiring layer and generate the driving signal;

[0177] The first power supply wiring is disposed in the first wiring layer and is wiring for supplying drive power to the driving device;

[0178] A differential line, configured on the first wiring layer and used for transmitting differential signals to the driving device; and

[0179] A second power supply cabling, disposed on the second cabling layer, is electrically connected to the first power supply cabling via the first via and faces the first region in the differential circuit.

[0180] The width of the second power supply wiring is greater than the width of the first region in the differential circuit.

[0181] (2) The driving substrate described in (1) above further comprises:

[0182] A first grounding wiring, disposed on the first wiring layer, is a wiring for supplying ground to the driving device for the driving power supply; and

[0183] A second grounding wiring is disposed on the second wiring layer, electrically connected to the first grounding wiring via a second via, and opposite to the second region in the differential line.

[0184] The width of the second grounding wiring is greater than the width of the second region in the differential line.

[0185] (3) The driving substrate described in (2) above further comprises:

[0186] A driving capacitor is disposed on the second wiring layer, with one end connected to the second power supply wiring and the other end connected to the second ground wiring;

[0187] A wiring area, configured in the first wiring layer, includes signal wiring for transmitting the drive signal output from the driving device; and

[0188] The return wiring has a wiring opposition area opposite to the wiring area and is configured in the second wiring layer in a manner connected to the second ground wiring.

[0189] (4) According to the driving substrate described in (3) above, wherein,

[0190] The return wiring includes:

[0191] The first return path extends from the wiring opposite region via one end of the driving device to the driving capacitor; and

[0192] The second return path extends from the wiring opposite region through the other end of the driving device to the driving capacitor.

[0193] (5) The driving substrate according to any one of (2) to (4) above further comprises:

[0194] A pair of first digital grounding wirings, which are arranged on both sides of the differential line along the width direction in the first wiring layer; and

[0195] The second digital grounding cabling is disposed on the second cabling layer, electrically connected to the pair of first digital grounding cablings via the third via and opposite to the third region in the differential line.

[0196] (6) The driving substrate described in (5) above, wherein,

[0197] In the second wiring layer, a gap region is provided between the opposite region of the first region of the differential line in the second power wiring and the opposite region of the second region of the differential line in the second ground wiring.

[0198] A protrusion is provided in the region of the first wiring layer opposite to the gap region, protruding from at least one of the pair of first digital grounding wirings.

[0199] (7) The driving board according to any one of (1) to (6) above, wherein,

[0200] It also includes: first and second input terminals, which receive the differential signal from outside the liquid injection head.

[0201] The plurality of driving devices are connected in series in the first wiring layer via a plurality of differential lines disposed between the first input terminal and the second input terminal.

[0202] (8) The driving board according to any one of (1) to (7) above, wherein,

[0203] The driving substrate is made of a flexible substrate.

[0204] (9) A liquid injection head, comprising:

[0205] One or more drive substrates described in any one of (1) to (8) above; and

[0206] The jet section.

[0207] (10) A liquid jet recording device, comprising:

[0208] The liquid injection head described in (9) above.

[0209] [Label Explanation]

[0210] 1 Inkjet head; 10 Connector; 11 Jet section; 111 Actuator plate; 112 Nozzle plate; 12 I / F substrate; 120a, 120b, 120c, 120d Connectors; 121 Circuit configuration area; 13, 13a, 13b, 13c, 13d, 13A, 13B Flexible substrate; 130 Connecting electrode; 131 Dielectric layer (substrate material); 141, 142 Cooling unit; 2 Printing control unit; 3 Ink tank; 30 Ink supply tube; 40 Component configuration area; 41 Driving device; 411 First driving device; 415 Second driving device; 412-414 Third driving device; 433 Crimping electrode; 5 Printer; 9 Ink; P Recording paper; Hn Nozzle orifice; Dt Transmit data; Sc Printing control signal; Sd Drive signal; Vd Drive voltage; S1 Surface; S2 Back side; Tin1 First input terminal; Tin2 Second input terminal; Tio1 First input / output section; Tio2 Second input / output section; Tp Power supply terminal section; Tc Control terminal section; Td Drive terminal section; Lt1 First differential circuit; Lt2 Second differential circuit; Lt31~Lt34 Third differential circuit; Ld Drive power line; W1 First wiring layer; W2 Second wiring layer; Wp1 First power supply wiring; Wp2 Second power supply wiring; Wg1 First ground wiring; Wg2 Second ground wiring; Wdg1 First digital ground wiring; Wdg2 Second digital ground wiring; Wr Return wiring; Ws Signal wiring; TH1 First via; TH2 Second via; TH3 Third via; dp2, dg2, ddg2 Width; dL1, dL2, dL3 Width; Pr1 First return path; Pr2 Second return path; Cd driving capacitor; A1 first region; A2 second region; Aws1 wiring region; Aws2 wiring opposite region; Ag gap region; Pj protrusion.

Claims

1. A drive board, adapted for a liquid jet head having a jetting section for jetting liquid, and outputting a drive signal for jetting liquid to the jetting section, comprising: The first wiring layer and the second wiring layer are positioned opposite each other along a direction orthogonal to the substrate surface; One or more driving devices are mounted on the first wiring layer and generate the driving signal; The first power supply wiring is disposed in the first wiring layer and is wiring for supplying drive power to the driving device; A differential line, which is configured in the first wiring layer and is a line for transmitting differential signals to the driving device; as well as A second power supply cabling, disposed on the second cabling layer, is electrically connected to the first power supply cabling via the first via and faces the first region in the differential circuit. The width of the second power supply wiring is greater than the width of the first region in the differential circuit. The driving substrate also includes: The first grounding wiring is disposed in the first wiring layer and is a wiring for supplying ground to the driving device for the driving power supply; as well as A second grounding wiring is disposed on the second wiring layer, electrically connected to the first grounding wiring via a second via, and opposite to the second region in the differential line. The width of the second grounding wiring is greater than the width of the second region in the differential line.

2. The driving substrate as described in claim 1, further comprising: A driving capacitor is disposed on the second wiring layer, with one end connected to the second power supply wiring and the other end connected to the second ground wiring; A wiring area, configured in the first wiring layer, includes signal wiring for transmitting the drive signal output from the driving device; and The return wiring has a wiring opposition area opposite to the wiring area and is configured in the second wiring layer in a manner connected to the second ground wiring.

3. The driving substrate as described in claim 2, wherein, The return wiring includes: The first return path extends from the wiring opposite region through one end of the driving device to the driving capacitor; as well as The second return path extends from the wiring opposite region through the other end of the driving device to the driving capacitor.

4. The driving substrate according to any one of claims 1 to 3, further comprising: A pair of first digital grounding wirings, which are arranged on both sides of the differential line along the width direction in the first wiring layer; and The second digital grounding cabling is disposed on the second cabling layer, electrically connected to the pair of first digital grounding cablings via the third via and opposite to the third region in the differential line.

5. The driving substrate as claimed in claim 4, wherein, In the second wiring layer, a gap region is provided between the opposite region of the first region of the differential line in the second power wiring and the opposite region of the second region of the differential line in the second ground wiring. A protrusion is provided in the region of the first wiring layer opposite to the gap region, protruding from at least one of the pair of first digital grounding wirings.

6. The driving substrate according to any one of claims 1 to 3, wherein, It also includes: first and second input terminals, which receive the differential signal from outside the liquid injection head. The plurality of driving devices are connected in series in the first wiring layer via a plurality of differential lines disposed between the first input terminal and the second input terminal.

7. The driving substrate according to any one of claims 1 to 3, wherein, The driving substrate is made of a flexible substrate.

8. A drive board, adapted for a liquid jet head having a jetting section for jetting liquid and outputting a drive signal for jetting liquid to the jetting section, comprising: The first wiring layer and the second wiring layer are positioned opposite each other along a direction orthogonal to the substrate surface; One or more driving devices are mounted on the first wiring layer and generate the driving signal; The first power supply wiring is disposed in the first wiring layer and is wiring for supplying drive power to the driving device; A differential line, which is configured in the first wiring layer and is a line for transmitting differential signals to the driving device; as well as A second power supply cabling, disposed on the second cabling layer, is electrically connected to the first power supply cabling via the first via and faces the first region in the differential circuit. The width of the second power supply wiring is greater than the width of the first region in the differential circuit. The driving substrate also includes: A driving capacitor is disposed on the second wiring layer, with one end connected to the second power supply wiring and the other end connected to the second ground wiring opposite to the second region in the differential line; A wiring area, configured in the first wiring layer, includes signal wiring for transmitting the drive signal output from the driving device; and The return wiring has a wiring opposition area opposite to the wiring area and is configured in the second wiring layer in a manner connected to the second ground wiring.

9. The driving substrate as claimed in claim 8, further comprising: A first grounding wiring, disposed on the first wiring layer, is used to supply ground to the driving device for the drive power supply; and A second grounding wiring is disposed on the second wiring layer, electrically connected to the first grounding wiring via a second via, and opposite to the second region in the differential line. The width of the second grounding wiring is greater than the width of the second region in the differential line.

10. The driving substrate as claimed in claim 8, wherein, The return wiring includes: The first return path extends from the wiring opposite region through one end of the driving device to the driving capacitor; as well as The second return path extends from the wiring opposite region through the other end of the driving device to the driving capacitor.

11. The driving substrate according to any one of claims 8 to 10, further comprising: A pair of first digital grounding wirings, which are arranged on both sides of the differential line along the width direction in the first wiring layer; and The second digital grounding cabling is disposed on the second cabling layer, electrically connected to the pair of first digital grounding cablings via the third via and opposite to the third region in the differential line.

12. The driving substrate as claimed in claim 11, wherein, In the second wiring layer, a gap region is provided between the opposite region of the first region of the differential line in the second power wiring and the opposite region of the second region of the differential line in the second ground wiring. A protrusion is provided in the region of the first wiring layer opposite to the gap region, protruding from at least one of the pair of first digital grounding wirings.

13. The driving substrate according to any one of claims 8 to 10, wherein, It also includes: first and second input terminals, which receive the differential signal from outside the liquid injection head. The plurality of driving devices are connected in series in the first wiring layer via a plurality of differential lines disposed between the first input terminal and the second input terminal.

14. The driving substrate according to any one of claims 8 to 10, wherein, The driving substrate is made of a flexible substrate.

15. A liquid injection head, comprising: One or more driving substrates as described in any one of claims 1 to 14; and The jet section.

16. A liquid jet recording device comprising the liquid jet head of claim 15.

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