Head chip, liquid jet head, liquid jet recording device and head chip manufacturing method

Abstract

To provide a head chip that can suppress a driving electrode from being disconnected and is excellent in reliability over the long term, a liquid jet head, a liquid jet recording device, and a head chip manufacturing method.SOLUTION: A head chip according to one embodiment described in the disclosure comprises: a pressure chamber in which liquid is stored; a chip main body having a driving part arranged at a portion facing the pressure chamber; a driving electrode formed on the driving part; and driving wiring formed on the chip main body to connect the driving electrode to external wiring. The driving wiring comprises a first wiring part which has a first region and a second region, connected in an extending direction of the driving wiring to the first region, whose cross sectional areas in a direction orthogonal to the extending direction are smaller than cross sectional areas of the first region, and a second wiring part leading, in a direction crossing the extending direction, at least to the second region.SELECTED DRAWING: Figure 7

Description

[Technical Field]

[0001] The present disclosure relates to a head chip, a liquid jet head, a liquid jet recording apparatus, and a method for manufacturing the head chip. [Background technology]

[0002] The head chip mounted on the inkjet printer includes an actuator plate in which ejection channels and non-ejection channels are formed, and a nozzle plate having nozzle holes communicating with the ejection channels. Individual electrodes are formed on the inner surfaces of the ejection channels along the extension direction of the ejection channels. Common electrodes are formed on the inner surfaces of the non-ejection channels along the extension direction of the non-ejection channels. In the head chip, the volume of the ejection channel is changed by applying a voltage between the common electrode and the individual electrodes, causing the thickness of the driving wall to slide and deform, causing the ink in the ejection channel to be ejected through the nozzle holes formed in the nozzle plate.

[0003] The individual electrodes and the common electrode are connected to external wiring via individual terminals and common terminals formed on the surface of the actuator plate (see, for example, Patent Document 1 below). In Patent Document 1 below, a separating groove is formed in a portion of the surface of the actuator plate located between the individual terminals and the common terminal, separating the individual terminals and the common terminal from each other. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-151495 Summary of the Invention [Problem to be solved by the invention]

[0005] However, in the above-mentioned conventional technology, the dividing grooves reach the inner surfaces of the non-ejection channels. Therefore, the cross-sectional area of ​​the common electrode perpendicular to the extension direction is smaller in the portion where the dividing grooves are formed than in the portion where the dividing grooves are not formed. In other words, the electrical resistance of the portion of the common electrode where the dividing grooves are formed is higher than the electrical resistance of the portion where the dividing grooves are not formed. As a result, the portion of the common electrode where the dividing grooves are formed can cause disconnection or other problems when a large current flows.

[0006] The present disclosure provides a head chip, a liquid jet head, a liquid jet recording apparatus, and a method for manufacturing the head chip, which are capable of suppressing breakage of drive electrodes and are highly reliable over a long period of time. [Means for solving the problem]

[0007] In order to solve the above problems, the present disclosure employs the following aspects. (1) A head chip according to one embodiment of the present disclosure comprises a chip body having a pressure chamber for containing a liquid and a drive unit arranged in a portion facing the pressure chamber, a drive electrode formed in the drive unit, and a drive wiring formed in the chip body and connecting the drive electrode and external wiring, wherein the drive wiring comprises a first wiring portion having a first region and a second region connected to the first region in the extension direction of the drive wiring and having a cross-sectional area perpendicular to the extension direction that is smaller than that of the first region, and a second wiring portion connected to at least the second region in a direction intersecting the extension direction.

[0008] According to this aspect, the second wiring portion of the drive wiring is formed so as to be connected to at least the second region of the first wiring portion, which has a cross-sectional area smaller than that of the first region, thereby reducing the maximum resistance of the entire drive wiring. This makes it possible to prevent the drive wiring from breaking even if an unexpectedly large current flows through the drive wiring. As a result, it is possible to provide a head chip with excellent reliability over a long period of time.

[0009] (2) In the head chip according to the above aspect (1), it is preferable that the second wiring portion is provided only in a part of the drive wiring that includes the second region. According to this aspect, since the second wiring section is provided only in a part including the second region, the increase in material costs for the drive wiring due to the addition of the second wiring section can be suppressed compared to when the second wiring section is formed to cover the entire first wiring section.

[0010] (3) In the head chip according to the above aspect (1) or (2), it is preferable that the second wiring portion is arranged to cover at least the second region in a first direction perpendicular to the deposition surface of the drive wiring in the chip body when viewed from the extension direction. According to this aspect, the second wiring portion is provided to cover the second region, which prevents the drive wiring from increasing in size along the deposition surface due to the addition of the second wiring portion, thereby reducing the maximum resistance of the entire drive wiring while suppressing an increase in capacitance.

[0011] (4) In a head chip according to any one of the above aspects (1) to (3), it is preferable that the second wiring portion is arranged so as to be integrally connected to at least the second region in a second direction along the film formation surface of the drive wiring in the chip body when viewed from the extension direction. According to this aspect, the second wiring portion is connected to the second region in a direction along the film formation surface, which further reduces the risk of wire breakage, etc. In particular, by ensuring the width dimension of the drive wiring as in this aspect, the risk of film formation defects due to foreign matter adhesion can be reduced compared to when the thickness of the drive wiring is ensured, when the cross-sectional area perpendicular to the extension direction is the same.

[0012] (5) In a head chip according to any one of the aspects (1) to (4) above, the chip body includes an actuator plate formed by stacking two piezoelectric substrates having different polarization directions in the second direction in the second direction, and the actuator plate is formed with an ejection channel as the pressure chamber in which liquid is contained, and a non-ejection channel adjacent to the ejection channel and in which no liquid is contained, the drive unit is formed by a portion of the actuator plate located between the ejection channel and the non-ejection channel, and the drive electrode includes a common electrode formed over the entire area in the second direction in a portion of the drive unit facing the ejection channel, and an individual electrode formed over the entire area in the second direction in a portion of the drive unit facing the non-ejection channel, and the drive wiring is preferably connected to the individual electrode in a portion of the drive unit facing the non-ejection channel. According to this aspect, in an actuator plate made of two piezoelectric substrates with different polarization directions, it is necessary to form drive electrodes (e.g., individual electrodes) over the entire area of ​​the drive section in the second direction. Therefore, by forming drive wiring in a portion of the drive section facing the non-ejection channel, the drive wiring can be expanded in the second direction by the second wiring section when forming the individual electrodes. This eliminates the need for a separate wiring formation process for forming the second wiring section, thereby suppressing a decrease in manufacturing efficiency due to the formation of the second wiring section.

[0013] (6) In a head chip according to any one of the above aspects (1) to (5), a dividing groove is formed on the surface of the actuator plate to separate a common terminal that connects the common electrode and the external wiring, and an individual terminal that connects the individual electrode and the external wiring, and the second region is preferably located in a portion of the drive unit facing the non-ejection channel that overlaps with the dividing groove in the extension direction. According to this aspect, the second wiring portion is formed in the portion that overlaps the dividing groove in the extension direction, thereby suppressing short circuits between the common terminal and the individual terminals and reducing the maximum resistance value for the entire drive wiring.

[0014] (7) A liquid jet head according to one aspect of the present disclosure includes the head chip according to any one of the above aspects (1) to (6). According to this aspect, it is possible to provide a liquid jet head with excellent reliability.

[0015] (8) A liquid jet recording apparatus according to one aspect of the present disclosure includes the liquid jet head according to the above aspect (7). According to this aspect, it is possible to provide a highly reliable liquid jet recording apparatus.

[0016] (9) A method for manufacturing a head chip according to one aspect of the present disclosure includes a drive wiring forming process for forming drive wiring connecting the drive electrodes and external wiring on a chip body having a pressure chamber for containing a liquid and a drive section disposed facing the pressure chamber and having drive electrodes formed thereon, wherein the drive wiring forming process forms a second wiring section on the chip body having a first wiring section formed thereon, the first wiring section having a first region and a second region connected to the first region in the extension direction of the drive wiring and having a cross-sectional area perpendicular to the extension direction that is smaller than the first region, so that the second wiring section is connected to at least the second region in a direction intersecting the extension direction. [Effects of the Invention]

[0017] According to one aspect of the present disclosure, it is possible to provide a head chip, a liquid jet head, a liquid jet recording apparatus, and a method for manufacturing a head chip that are capable of suppressing breakage of drive electrodes and have excellent reliability over a long period of time. [Brief explanation of the drawings]

[0018] [Figure 1] 1 is a schematic diagram of a printer according to a first embodiment. [Figure 2] FIG. 2 is a schematic diagram illustrating the configuration of an inkjet head and an ink circulation mechanism according to the first embodiment. [Figure 3] FIG. 2 is an exploded perspective view of the head chip according to the first embodiment. [Figure 4] FIG. 4 is a cross-sectional view taken along line IV-IV in FIG. [Figure 5] FIG. 4 is a cross-sectional view taken along line VV in FIG. [Figure 6] FIG. 6 is a cross-sectional view corresponding to the line VI-VI in FIG. 5. [Figure 7] FIG. 7 is a cross-sectional view corresponding to line VII-VII in FIG. 5. [Figure 8] FIG. 8 is a cross-sectional view corresponding to line VIII-VIII in FIG. [Figure 9] FIG. 9 is an enlarged view of part IX in FIG. 4. [Figure 10] FIG. 5 is a cross-sectional view corresponding to the line XX in FIG. 4. [Figure 11] 4 is a flowchart for explaining a method for manufacturing a head chip according to the first embodiment. [Figure 12] 3A to 3C are process diagrams illustrating a method for manufacturing a head chip according to the first embodiment. [Figure 13] 3A to 3C are process diagrams illustrating a method for manufacturing a head chip according to the first embodiment. [Figure 14] 3A to 3C are process diagrams illustrating a method for manufacturing a head chip according to the first embodiment. [Figure 15] 3A to 3C are process diagrams illustrating a method for manufacturing a head chip according to the first embodiment. [Figure 16] 3A to 3C are process diagrams illustrating a method for manufacturing a head chip according to the first embodiment. [Figure 17] 3A to 3C are process diagrams illustrating a method for manufacturing a head chip according to the first embodiment. [Figure 18] 3A to 3C are process diagrams illustrating a method for manufacturing a head chip according to the first embodiment. [Figure 19] 3A to 3C are process diagrams illustrating a method for manufacturing a head chip according to the first embodiment. [Figure 20] 3A to 3C are process diagrams illustrating a method for manufacturing a head chip according to the first embodiment. [Figure 21] 3A to 3C are process diagrams illustrating a method for manufacturing a head chip according to the first embodiment. [Figure 22] 3A to 3C are process diagrams illustrating a method for manufacturing a head chip according to the first embodiment. [Figure 23] 3A to 3C are process diagrams illustrating a method for manufacturing a head chip according to the first embodiment. [Figure 24] 3A to 3C are process diagrams illustrating a method for manufacturing a head chip according to the first embodiment. [Figure 25] 3A to 3C are process diagrams illustrating a method for manufacturing a head chip according to the first embodiment. [Figure 26] FIG. 6 is a cross-sectional view of a head chip according to a second embodiment, corresponding to FIG. 5. [Figure 27] FIG. 8 is a cross-sectional view of a portion of a head chip according to a second embodiment, the portion corresponding to FIG. 7. [Figure 28] FIG. 6 is a cross-sectional view corresponding to FIG. 5 of a head chip according to a modified example. [Figure 29] 8 is a cross-sectional view of a portion of a head chip according to a modified example, the portion corresponding to FIG. 7. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0019] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In the embodiments and modified examples described below, corresponding components may be designated by the same reference numerals and their description may be omitted. In the following description, expressions indicating relative or absolute arrangements, such as "parallel," "orthogonal," "center," and "coaxial," not only strictly refer to such arrangements, but also refer to a state in which there is a relative displacement with a tolerance or an angle or distance that provides the same function. In the following embodiments, an inkjet printer (hereinafter simply referred to as a printer) that records on a recording medium using ink (liquid) will be described as an example. In the drawings used in the following description, the scale of each component has been appropriately changed to make each component recognizable.

[0020] (First embodiment) [Printer 1] FIG. 1 is a schematic diagram of the printer 1. As shown in FIG. 1, the printer (liquid jet recording apparatus) 1 of the first embodiment includes a pair of transport mechanisms 2 and 3, an ink tank 4, an inkjet head (liquid jet head) 5, an ink circulation mechanism 6, and a scanning mechanism 7.

[0021] In the following explanation, an X, Y, Z Cartesian coordinate system will be used as necessary. In this case, the X direction corresponds to the transport direction (sub-scanning direction) of the recording medium P (e.g., paper, etc.). The Y direction corresponds to the scanning direction (main scanning direction) of the scanning mechanism 7. The Z direction indicates the height direction (gravity direction) perpendicular to the X and Y directions. In the following explanation, of the X, Y, and Z directions, the arrow side in the figure is the plus (+) side, and the opposite side to the arrow is the minus (-) side. In the first embodiment, the +Z side corresponds to the upward direction in the direction of gravity, and the -Z side corresponds to the downward direction in the direction of gravity.

[0022] The transport mechanisms 2 and 3 transport the recording medium P to the +X side. The transport mechanisms 2 and 3 each include a pair of rollers 11 and 12 extending in the Y direction, for example. The ink tanks 4 each contain four colors of ink, for example, yellow, magenta, cyan, and black. Each inkjet head 5 is configured to be able to eject the four colors of ink, yellow, magenta, cyan, and black, respectively, according to the ink tank 4 connected to it.

[0023] FIG. 2 is a schematic diagram of the inkjet head 5 and the ink circulation mechanism 6. As shown in FIG. 1 and 2, the ink circulation mechanism 6 circulates ink between the ink tank 4 and the inkjet head 5. Specifically, the ink circulation mechanism 6 includes a circulation flow path 23 having an ink supply pipe 21 and an ink discharge pipe 22, a pressure pump 24 connected to the ink supply pipe 21, and a suction pump 25 connected to the ink discharge pipe 22.

[0024] The pressure pump 24 pressurizes the ink supply pipe 21 and sends ink to the inkjet head 5 through the ink supply pipe 21. As a result, the ink supply pipe 21 side relative to the inkjet head 5 becomes a positive pressure. The suction pump 25 reduces the pressure inside the ink discharge pipe 22 and sucks ink from the inkjet head 5 through the ink discharge pipe 22. This creates a negative pressure on the ink discharge pipe 22 side relative to the inkjet head 5. By driving the pressure pump 24 and the suction pump 25, the ink can be circulated between the inkjet head 5 and the ink tank 4 through the circulation flow path 23.

[0025] The scanning mechanism 7 moves the inkjet head 5 back and forth in the Y direction. The scanning mechanism 7 includes a guide rail 28 extending in the Y direction, and a carriage 29 movably supported on the guide rail 28.

[0026] <Inkjet head 5> As shown in Fig. 1, the inkjet head 5 is mounted on a carriage 29. In the illustrated example, a plurality of inkjet heads 5 are mounted side by side in the Y direction on one carriage 29. The inkjet head 5 includes a head chip 50 (see Fig. 3), an ink supply unit (not shown) that connects the ink circulation mechanism 6 and the head chip 50, and a control unit (not shown) that applies a drive voltage to the head chip 50.

[0027] <Head chip 50> Fig. 3 is an exploded perspective view of the head chip 50. Fig. 4 is a cross-sectional view taken along line IV-IV in Fig. 3. Fig. 5 is a cross-sectional view taken along line VV in Fig. 3. As shown in Figures 3 to 5, the head chip 50 is a so-called edge shoot type that ejects ink from the tip of the ejection channel 71 (described later) in the channel extension direction (Z direction), and is a circulation type (vertical circulation type) that circulates ink between the ink tank 4.

[0028] The head chip 50 includes a first chip module 51A, a second chip module 51B, a feedback plate 52, and a nozzle plate 53. In the following explanation, the configuration of each chip module 51A, 51B will be explained using the first chip module 51A as an example. Therefore, in the second chip module 51B, the same configuration as the first chip module 51A will be assigned the same reference numerals as the first chip module 51A, and explanations thereof may be omitted.

[0029] <First chip module 51A> The first chip module 51A includes a first actuator plate 61, a first cover plate 62, and a first back plate 63. In the following description, the +Y side of the first chip module 51A will be referred to as the front side, and the -Y side as the back side.

[0030] The first actuator plate 61 is a laminated substrate (so-called chevron type) in which two piezoelectric substrates are stacked together, with the polarization directions being different in the thickness direction (Y direction (second direction)). Note that a ceramic substrate made of PZT (lead zirconate titanate) or the like is preferably used as the piezoelectric substrate. However, the first actuator plate 61 may also be formed from a single piezoelectric substrate with the polarization direction set in one direction (so-called monopole type).

[0031] The first actuator plate 61 is formed with ejection channels (ejection channels) 71 that are filled with ink and non-ejection channels 72 that are not filled with ink. The channels 71, 72 are alternately arranged at intervals in the X direction (first direction) on the first actuator plate 61 to form a channel row 70. In this embodiment, a configuration will be described in which the channel extension direction coincides with the Z direction (extension direction), but the channel extension direction may also intersect with the Z direction.

[0032] 3 and 4, the upper end of the discharge channel 71 terminates inside the first actuator plate 61, and the lower end opens at the lower end surface of the first actuator plate 61. Meanwhile, the upper part of the discharge channel 71 has a depth in the Y direction that gradually decreases toward the top. The lower part of the discharge channel 71 penetrates the first actuator plate 61 in the Y direction. 3 and 5, the non-ejection channels 72 penetrate the first actuator plate 61 in the Z direction. The non-ejection channels 72 penetrate the first actuator plate 61 in the Y direction over the entire length in the Z direction. That is, the depth of the non-ejection channels 72 in the Y direction is uniform over the entire length in the Z direction.

[0033] The portions of the first actuator plate 61 located between the discharge channel 71 and the non-discharge channel 72 each constitute a drive wall 75. Therefore, the discharge channel 71 is surrounded on both sides in the X direction by a pair of drive walls 75. The portion of the first actuator plate 61 located above the discharge channel 71 constitutes a tail portion 76.

[0034] <First cover plate 62> 3 to 5, the first cover plate 62 is joined to the surface of the first actuator plate 61. Specifically, the first cover plate 62 closes the front-side openings of the channels 71, 72 while leaving the surface of the tail portion 76 exposed. The lower end surface of the first cover plate 62 is disposed flush with the lower end surface of the first actuator plate 61.

[0035] A common ink chamber 80 is formed in the first cover plate 62 at a position overlapping the top of the ejection channel 71 when viewed from the Y direction. The common ink chamber 80 extends in the X direction, for example, to a length spanning the channel row 70, and opens on the surface of the first cover plate 62. The common ink chamber 80 is indirectly connected to the ink supply pipe 21 through an inlet port (not shown). In the common ink chamber 80, slits 81 are formed separately at positions that overlap the upper portions of the ejection channels 71 when viewed from the Y direction. The slits 81 communicate between the inside of the ejection channels 71 and the inside of the common ink chamber 80 through the upper portions of the ejection channels 71. Therefore, the common ink chamber 80 communicates with each of the ejection channels 71 through each slit 81, but does not communicate with each of the non-ejection channels 72.

[0036] <First Back Plate 63> The first back plate 63 is joined to the back surface of the first actuator plate 61. The first back plate 63 has the same external shape as the first actuator plate 61 when viewed from the Y direction. The first back plate 63 is superimposed on the entire first actuator plate 61 when viewed from the Y direction. In other words, the first back plate 63 closes the back surface openings of each of the channels 71, 72.

[0037] As shown in FIG. 3, the first actuator plate 61 is provided with common wiring 85 and individual wiring 86 as drive wiring. As shown in FIGS. 3 and 4, the common wiring 85 includes a common electrode 87 and a common terminal 88. The common electrodes 87 are formed on inner surfaces of the ejection channel 71 that face each other in the X direction. In the illustrated example, the common electrode 87 is formed on the entire inner surface of the ejection channel 71 in the Y and Z directions. It is sufficient that the common electrode 87 is formed on a portion of the inner surface of the ejection channel 71 that is located at least below the lower opening edge of the slit 81.

[0038] 4, the common electrode 87 according to the first embodiment is formed by a front-side common portion 87a and a back-side common portion 87b over the entire area in the Y direction on the inner surface of the ejection channel 71. Specifically, the front-side common portion 87a constitutes the front-side region of the common electrode 87. Specifically, the +Y side edge of the front-side common portion 87a coincides with the front-side opening edge of the ejection channel 71. The -Y side edge of the front-side common portion 87a is located on the -Y side of the center of the Y direction on the inner surface of the ejection channel 71. The rear surface side common portion 87b constitutes a rear surface side region of the common electrode 87. Specifically, the -Y side edge of the rear surface side common portion 87b coincides with the rear surface side opening edge of the ejection channel 71. The +Y side edge of the rear surface side common portion 87b is located on the +Y side of the center in the Y direction of the inner surface of the ejection channel 71. In other words, a part of the rear surface side common portion 87b overlaps with the front surface side common portion 87a in a portion of the inner surface of the ejection channel 71 that includes the center in the Y direction.

[0039] 3, the common terminal 88 is formed on the surface of the tail portion 76. The common terminals 88 are provided on the surface of the tail portion 76 corresponding to each discharge channel 71. Each common terminal 88 extends linearly in the Z direction above the corresponding discharge channel 71. The lower end of the common terminal 88 is connected to the common electrode 87 at the upper opening edge of the discharge channel 71.

[0040] As shown in FIGS. 3 and 5, the individual wiring 86 includes an individual electrode 91, an individual terminal 92, a lead wiring 93, and a bypass wiring 94. The individual electrodes 91 are formed on the lower portions of the inner surfaces of the non-ejection channels 72 that face each other in the X direction. Specifically, the lower edges of the individual electrodes 91 coincide with the lower opening edges of the non-ejection channels 72. The upper edges of the individual electrodes 91 are located within the height range of the common ink chamber 80. That is, at least a portion of the individual electrodes 91 faces the common electrode 87 in the X direction, with the drive wall 75 sandwiched between them. In the illustrated example, the individual electrodes 91 are formed over the entire length in the Z direction and across the entire area of ​​the non-ejection channels 72 in the Y direction. Note that it is sufficient that the individual electrodes 91 are formed in a portion that is at least located below the lower opening edges of the slits 81.

[0041] 5, the individual electrode 91 according to the first embodiment is formed by a front-side individual part 91a and a back-side individual part 91b over the entire area in the Y direction on the inner surface of the non-ejection channel 72. Specifically, the front-side individual part 91a constitutes the front-side region of the individual electrode 91. Specifically, the +Y side edge of the front-side individual part 91a coincides with the front-side opening edge of the non-ejection channel 72. The -Y side edge of the front-side individual part 91a is located on the -Y side of the center of the Y direction on the inner surface of the non-ejection channel 72. The back-side individual portion 91b constitutes a back-side region of the individual electrode 91. Specifically, the -Y side edge of the back-side individual portion 91b coincides with the back-side opening edge of the non-ejection channel 72. The +Y side edge of the back-side individual portion 91b is located on the +Y side of the center in the Y direction of the inner surface of the non-ejection channel 72. In other words, a portion of the back-side individual portion 91b overlaps with the front-side individual portion 91a in a portion of the inner surface of the non-ejection channel 72 that includes the center in the Y direction.

[0042] The individual terminals 92 are formed on the surface of the tail portion 76 in a portion located above the common terminal 88. The individual terminals 92 are formed in a strip shape extending in the X direction. The individual terminals 92 reach the surface-side opening edges of the non-ejection channels 72 that face each other in the X direction, sandwiching the ejection channel 71 therebetween. A separating groove 79 is formed in the tail portion 76 in a portion located between the common terminal 88 and the individual terminals 92. The separating groove 79 opens on the surface of the tail portion 76 and extends in the X direction. The separating groove 79 separates the common terminal 88 and the individual terminals 92. The depth of the separating groove 79 in the Y direction is formed to be less than half the thickness of the first actuator plate 61. However, the depth of the separating groove 79 can be changed as appropriate.

[0043] The lead wiring 93 is a wiring that connects between the individual electrodes 91 and the individual terminals 92. The lead wiring 93 includes a first wiring portion 95 and a second wiring portion 96. The first wiring portion 95 is a base wiring of the lead wiring 93. The first wiring portion 95 extends upward from the individual electrode 91 on the inner surface of the non-ejection channel 72. The first wiring portion 95 extends over the entire length in the Z direction in a portion of the inner surface of the non-ejection channel 72 that is located above the common electrode 87. Specifically, the first wiring portion 95 includes a first region 95a, a second region 95b, and a third region 95c.

[0044] The first region 95a is a portion of the inner surface of the non-ejection channel 72 that is located between the individual electrode 91 and the separating groove 79. The first region 95a extends in the Z direction with a uniform width in the Y direction. The width of the first region 95a in the Y direction is formed to be less than the thickness of the first actuator plate 61. In the illustrated example, the first region 95a is formed to have the same width as the front-side individual portion 91a. Specifically, the front-side edge of the first region 95a reaches the front-side opening edge of the non-ejection channel 72. The back-side edge of the first region 95a is located on the -Y side of the center of the non-ejection channel 72 in the Y direction.

[0045] The second region 95b extends upward from the first region 95a. The second region 95b is a portion of the inner surface of the non-ejection channel 72 that is located within the height range of the separating groove 79. That is, the second region 95b extends in the Z direction over the entire length of the separating groove 79 from the portion of the inner surface of the non-ejection channel 72 that is located on the -Y side of the separating groove 79. The width of the second region 95b in the Y direction is uniform over the entire length in the Z direction. Specifically, the front side edge of the second region 95b reaches the back side edge of the dividing groove 79. The back side edge of the second region 95b is located at the same position in the Y direction as the back side edge of the first region 95a. In other words, the width of the second region 95b in the Y direction is narrower than that of the first region 95a by the depth of the dividing groove 79.

[0046] The third region 95c extends upward from the second region 95b. The third region 95c extends in the Z direction through a portion of the inner surface of the non-ejection channel 72 that is located above the dividing groove 79. The upper edge of the third region 95c reaches the upper opening edge of the non-ejection channel 72. The width of the third region 95c in the Y direction is equal to that of the first region 95a. That is, the front side edge of the third region 95c reaches the front side opening edge of the non-ejection channel 72. The back side edge of the third region 95c is located on the -Y side of the center of the non-ejection channel 72 in the Y direction. The above-mentioned individual terminals 92 connect the third regions 95c of the wiring 93 that face each other in the X direction, with the ejection channel 71 sandwiched between them, at the front side opening edge of the non-ejection channel 72.

[0047] Fig. 6 is a cross-sectional view taken along line VI-VI in Fig. 5. Fig. 7 is a cross-sectional view taken along line VII-VII in Fig. 5. 6 and 7, the thickness of the lead-out wiring 93 in the X direction (the dimension in the direction perpendicular to the inner surface of the non-ejection channel 72) is uniform throughout. Therefore, the cross-sectional area of ​​the lead-out wiring 93 in the cross section perpendicular to the Z direction is smallest in the second region 95b. That is, the electrical resistance of the lead-out wiring 93 in the second region 95b is greater than the electrical resistances in the first region 95a and the third region 95c.

[0048] 5 and 7, the second wiring portion 96 is a wiring formed in addition to the first wiring portion 95. The second wiring portion 96 is formed on the inner surface of the non-ejection channel 72 so as to be continuous with at least the second region 95b. In the Z direction, the second wiring portion 96 is formed so as to include the entire second region 95b and to straddle the boundary portion of the first region 95a with the second region 95b and the boundary portion of the third region 95c with the second region 95b. In other words, the second wiring portion 96 is provided only in a portion of the lead wiring 93 that includes the second region 95b.

[0049] In the Y direction, the second wiring portion 96 overlaps a portion of the first wiring portion 95 (the second region 95b) and protrudes toward the -Y side with respect to the second region 95b. Specifically, the front-side end of the second wiring portion 96 overlaps the back-side end of the second region 95b when viewed from the X direction. The back-side edge of the second wiring portion 96 reaches the back-side opening edge of the non-ejection channel 72. That is, the portion of the routing wiring 93 located within the height range of the dividing groove 79 is formed by the second region 95b and the second wiring portion 96 over the entire Y direction with respect to the inner surface of the non-ejection channel 72. Note that the overlap amount between the back-side end of the second region 95b and the front-side end of the second wiring portion 96 is preferably, for example, 10 μm or more, taking into account variations in deposition depth and the like. This ensures reliable conduction between the back-side end of the second region 95b and the front-side end of the second wiring portion 96.

[0050] As described above, the lead-out wiring 93 according to the first embodiment is configured by overlapping the second wiring portion 96 with a portion of the first wiring portion 95. In this case, the cross-sectional area of ​​the lead-out wiring 93 in a direction perpendicular to the Z direction is set to be larger than the cross-sectional area of ​​the second region 95b alone at any point in the Z direction. In other words, the electrical resistance of the lead-out wiring 93 is smaller than the electrical resistance of the second region 95b alone at any point in the Z direction.

[0051] The bypass wiring 94 is formed on the back surface of the actuator plate 61 in a portion facing the dividing groove 79 in the Y direction. The bypass wiring 94 is formed in a strip shape extending in the X direction. The bypass wiring 94 reaches the back surface opening edges of the non-ejection channels 72 that face each other in the X direction with the ejection channel 71 therebetween. The bypass wiring 94 connects the second wiring portions 96 that face each other in the X direction with the ejection channel 71 therebetween.

[0052] A flexible printed circuit board (not shown) serving as external wiring is crimped onto the surface of the tail portion 76. The flexible printed circuit board is connected to the common terminal 88 and the individual terminals 92 on the surface of the tail portion 76. The flexible printed circuit board connects the first chip module 51A and the control unit.

[0053] <Second chip module 51B> The second chip module 51B includes a second actuator plate 101, a second cover plate 102, and a second back plate 103. In the second chip module 51B, the second back plate 103, the second actuator plate 101, and the second cover plate 102 are stacked in order from the +Y side to the -Y side. The second chip module 51B is stacked on the first chip module 51A with the front surface side (-Y side) facing away from the first chip module 51A. Specifically, the first chip module 51A and the second chip module 51B are integrated by joining the back surfaces of the first back plate 63 and the second back plate 103. In this case, the lower end surfaces of the chip modules 51A and 51B are arranged flush with each other.

[0054] The ejection channels 71 and non-ejection channels 72 of the second tip module 51B are arranged at a half-pitch offset from the arrangement pitch of the ejection channels 71 and non-ejection channels 72 of the first tip module 51A. That is, the ejection channels 71 and non-ejection channels 72 of each tip module 51A, 51B are arranged in a staggered pattern. In this case, the ejection channels 71 of the first tip module 51A and the non-ejection channels 72 of the second tip module 51B face each other in the Y direction, and the non-ejection channels 72 of the first tip module 51A and the ejection channels 71 of the second tip module 51B face each other in the Y direction. Note that the pitch of the channels 71, 72 of each tip module 51A, 51B can be changed as appropriate.

[0055] <Return Plate 52> The feedback plate 52 is bonded to the lower end surfaces of the chip modules 51A, 51B together with an adhesive. The feedback plate 52 closes the lower end openings of the channels 71, 72. The feedback plate 52 is made of, for example, polyimide. The feedback plate 52 has a plurality of first communication paths 110 and a plurality of second communication paths 111 formed therein.

[0056] Fig. 8 is a cross-sectional view corresponding to the line VIII-VIII in Fig. 4. Fig. 9 is an enlarged view of part IX in Fig. 4. As shown in FIGS. 8 and 9 , the multiple first communication passages 110 are individually formed in the first tip module 51A at positions equivalent in the X direction to the respective discharge channels 71. In this embodiment, the multiple first communication passages 110 are formed at intervals in the X direction corresponding to the arrangement pitch of the discharge channels 71. Each first communication passage 110 is formed in a U-shape when viewed from the side in the X direction. Specifically, each first communication passage 110 includes an upstream opening 115, a downstream opening 116, and a connection portion 117. Since all the first communication passages 110 have the same configuration, the following configuration will be described in detail using one first communication passage 110 as an example.

[0057] The upstream opening 115 is formed at a position overlapping with the discharge channel 71 in a plan view. The upstream opening 115 has an upper end that opens on the upper surface of the return plate 52 and a lower end that terminates inside the return plate 52. The upstream opening 115 communicates with the inside of the discharge channel 71 through the lower end opening of the discharge channel 71. In the first embodiment, the flow path cross-sectional area of ​​the upstream opening 115 (cross-sectional area perpendicular to the Z direction) is uniform throughout the Z direction. However, the flow path cross-sectional area of ​​the upstream opening 115 may vary depending on the position in the Z direction.

[0058] At least a part of the opening edge of the upstream opening 115 is disposed outward from the lower end opening edge of the discharge channel 71 in a plan view. Specifically, the dimension of the upstream opening 115 in the X direction is smaller than the dimension of the lower end opening of the discharge channel 71 in the X direction. The dimension of the upstream opening 115 in the Y direction is larger than the dimension of the lower end opening of the discharge channel 71 in the Y direction. Portions of the lower end surface of the first tip module 51A located on both sides of the discharge channel 71 in the Y direction are exposed through the upstream opening 115.

[0059] The downstream opening 116 is formed at a position overlapping with the first back plate 63 in a plan view. The upper end of the downstream opening 116 opens at the upper surface of the feedback plate 52, and the lower end terminates inside the feedback plate 52. The dimension of the downstream opening 116 in the Z direction is equal to that of the upstream opening 115. In this embodiment, the flow path cross-sectional area of ​​the downstream opening 116 (cross-sectional area perpendicular to the Z direction) is uniform throughout the Z direction. However, the flow path cross-sectional area of ​​the downstream opening 116 may vary depending on the position in the Z direction.

[0060] The connecting portion 117 connects the upstream opening 115 and the downstream opening 116 to each other. The connecting portion 117 is open only on the lower surface of the feedback plate 52 and extends in the Y direction. The dimension of the connecting portion 117 in the Z direction is uniform over the entire area in the Y direction. In this embodiment, the dimension of the connecting portion 117 in the Z direction is larger than the dimensions of the upstream opening 115 and the downstream opening 116 in the Z direction. However, the dimension of the connecting portion 117 in the Z direction may vary depending on the position in the Y direction.

[0061] The connecting portion 117 has a dimension in the X direction in a plan view that is larger than the upstream opening 115 and the downstream opening 116. Specifically, the connecting portion 117 includes an upstream wide portion 117a and a downstream wide portion 117b. The upstream wide portion 117a is disposed at a position overlapping the upstream opening 115 in a plan view. The upstream wide portion 117a is slightly larger than the upstream opening 115 in a plan view. The upstream opening 115 is located on the downward-facing surface (bottom surface) of the inner surface of the upstream wide portion 117a. The downstream wide portion 117b extends from the upstream wide portion 117a toward the -Y side. The downstream wide portion 117b overlaps with the downstream opening 116 in a plan view. The downstream wide portion 117b is slightly larger than the downstream opening 116 in a plan view. The dimension of the downstream wide portion 117b in the X direction is smaller than that of the upstream wide portion 117a. The downstream opening 116 opens on the bottom surface of the downstream wide portion 117b.

[0062] 5, the second communication passages 111 are formed separately at positions in the X direction equivalent to the positions of the discharge channels 71 in the second tip module 51B. In this embodiment, the second communication passages 111 are formed at intervals in the X direction corresponding to the arrangement pitch of the discharge channels 71 in the second tip module 51B. That is, the first communication passages 110 and the second communication passages 111 are alternately arranged at intervals in the X direction. The second communication passages 111 have the same configuration as the first communication passages 110. Therefore, the same components of the second communication passages 111 as those of the first communication passages 110 are denoted by the same reference numerals, and detailed description of the second communication passages 111 will be omitted.

[0063] FIG. 10 is a cross-sectional view taken along line XX in FIG. 4 and 10, the first back plate 63 and the second back plate 103 are stacked on top of each other to form a flow path plate 120. The flow path plate 120 has a plurality of first connection paths 121, a plurality of second connection paths 122, and a manifold 123 formed therein.

[0064] The multiple first connection paths 121 are individually formed at positions overlapping with the downstream openings 116 of the respective first communication paths 110 in a plan view. The first connection paths 121 are arranged at intervals in the X direction at the same pitch as the first communication paths 110. Specifically, the first connection paths 121 open on the back surface of the first back plate 63. The back surface opening of the first connection paths 121 is closed by the second back plate 103.

[0065] The first connection path 121 extends linearly in the Z direction when viewed from the Y direction. The lower end of the first connection path 121 opens on the lower end surface of the first back plate 63. As a result, the lower end opening of the first connection path 121 communicates with the downstream opening 116. On the other hand, the upper end of the first connection path 121 terminates inside the first back plate 63.

[0066] 8, the dimension in the X direction of the lower end opening of the first connecting path 121 is larger than that of the downstream opening 116 and smaller than that of the downstream wide portion 117b. In this case, the opening edge of the downstream opening 116 protrudes inward relative to the lower end opening edge of the first connecting path 121. However, the dimension in the X direction of the lower end opening of the first connecting path 121 may be larger than that of the downstream wide portion 117b or smaller than that of the downstream opening 116.

[0067] 10, the plurality of second connection paths 122 are individually formed at positions overlapping with the downstream openings 116 of the respective second communication paths 111 in a plan view. The second connection paths 122 are arranged at intervals in the X direction at the same pitch as the second communication paths 111. That is, the first connection paths 121 and the second connection paths 122 are arranged alternately in the X direction.

[0068] As shown in FIGS. 5 and 8 , each second connection path 122 communicates with the downstream opening 116 of the corresponding second communication path 111. Specifically, the second connection path 122 opens on the back surface (surface facing the +Y side) of the second back plate 103. The back surface opening of the second connection path 122 is closed by the first back plate 63. The second connection path 122 extends in the Z direction. The lower end of the second connection path 122 opens on the lower end surface of the second back plate 103. As a result, the lower end opening of the second connection path 122 communicates with the downstream opening 116 of the second communication path 111. Meanwhile, the upper end of the second connection path 122 terminates inside the second back plate 103. The dimensions of the second connection path 122 can be set similarly to those of the first connection path 121.

[0069] The manifold 123 is formed in a portion of the flow path plate 120 located above the connection paths 121 and 122. The manifold 123 is formed by overlapping a first recess 123a formed in the first back plate 63 and a second recess 123b formed in the second back plate 103. The first recess 123a is a recess that opens on the back surface of the first back plate 63 and extends in the Z and Y directions. The second recess 123b is a recess that opens on the back surface of the second back plate 103 and extends in the Z and Y directions. The manifold 123 is formed by connecting the back surface side openings of the first recess 123a and the second recess 123b to each other. Note that the manifold 123 may be configured such that a recess formed in only one of the first back plate 63 and the second back plate 103 is closed by the back surface of the other back plate.

[0070] The connection paths 121, 122 are all connected to the manifold 123. Specifically, the upper end opening of each first connection path 121 is open on the lower end surface of the first recess 123a. The upper end opening of each second connection path 122 is open on the lower end surface of the second recess 123b. The manifold 123 is indirectly connected to the ink discharge tube 22 through an outlet port (not shown).

[0071] The chip modules 51A, 51B and the feedback plate 52 are covered with a protective film 125. In this embodiment, the protective film 125 is also formed on the inner surface of the common ink chamber 80, the inner surface of the slit 81, the inner surface of the ejection channel 71, the inner surface of each communication path 110, 111, the inner surface of each connection path 121, 122, and the inner surface of the manifold 123. The protective film 125 contains an organic insulating material such as a paraxylylene-based resin material (e.g., Parylene (registered trademark)) as an insulating material. The protective film 125 may be made of tantalum oxide (Ta2O5), silicon nitride (SiN), silicon carbide (SiC), silicon oxide (SiO2), diamond-like carbon, or the like, or may contain at least one of these.

[0072] <Nozzle plate 53> 3 to 5, the nozzle plate 53 is joined to the lower end surface of the feedback plate 52. The nozzle plate 53 has an array of nozzle holes (first nozzle holes 131 and second nozzle holes 132) that penetrate the nozzle plate 53 in the Z direction.

[0073] The plurality of first nozzle holes 131 are individually formed in the nozzle plate 53 at positions overlapping with the respective first communication passages 110 in a plan view. That is, the first nozzle holes 131 are arranged at intervals in the X direction at the same pitch as the first communication passages 110. The first nozzle holes 131 communicate with the corresponding discharge channels 71 of the first tip module 51A through the corresponding first communication passages 110. Specifically, each first nozzle hole 131 is formed at the +Y side end of each first communication passage 110 at a position overlapping with the discharge channel 71 and the upstream wide portion 117a in a plan view. Note that the first nozzle holes 131 may communicate with the first communication passages 110 at a position shifted in the Y direction relative to the discharge channels 71 of the first tip module 51A.

[0074] The multiple second nozzle holes 132 are individually formed in the nozzle plate 53 at positions overlapping with the respective second communication passages 111 in a plan view. That is, the second nozzle holes 132 are arranged at intervals in the X direction at the same pitch as the second communication passages 111. The second nozzle holes 132 communicate with the corresponding discharge channels 71 of the second tip module 51B through the corresponding second communication passages 111. Specifically, each second nozzle hole 132 is formed at the -Y side end of each second communication passage 111 at a position overlapping with the discharge channel 71 and the upstream wide portion 117a in a plan view. Note that the second nozzle holes 132 may communicate with the second communication passages 111 at a position offset in the Y direction from the discharge channel 71 of the second tip module 51B.

[0075] [Printer 1 operation method] Next, a case where characters, figures, etc. are recorded on the recording medium P using the printer 1 configured as described above will be described below. 1 are each fully filled with ink of a different color. The ink in the ink tanks 4 is then transferred to the inkjet head 5 via the ink circulation mechanism 6.

[0076] When the printer 1 is operated in this initial state, the recording medium P is conveyed to the +X side while being sandwiched between the rollers 11 and 12. At the same time as the recording medium P is conveyed, the carriage 29 moves in the Y direction, and the inkjet head 5 mounted on the carriage 29 moves back and forth in the Y direction.

[0077] The movement of each inkjet head 5 will now be described in detail. In a vertical circulation type head chip 50 such as that of this embodiment, ink is first circulated through the circulation flow path 23 by operating the pressure pump 24 and suction pump 25 shown in FIG. 2. In this case, ink circulating through the ink supply pipe 21 flows into the common ink chamber 80 of each chip module 51 through the inlet port. The ink that has flowed into each common ink chamber 80 is supplied to each ejection channel 71 through the slit 81. The ink that has flowed into each ejection channel 71 passes through each communication path 110, 111 and each connection path 121, 122, gathers in the manifold 123, and is then discharged to the ink discharge pipe 22 through the outlet port. The ink discharged to the ink discharge pipe 22 is returned to the ink tank 4 and then supplied again to the ink supply pipe 21. In this way, ink is circulated between the inkjet head 5 and the ink tank 4.

[0078] When the carriage 29 starts reciprocating, a drive voltage is applied to the electrodes 87, 91 via the flexible substrate. At this time, the drive voltage is applied between the electrodes 87, 91 with the individual electrode 91 at drive potential Vdd and the common electrode 87 at reference potential GND. This causes thickness shear deformation in the two drive walls 75 that define the ejection channel 71, causing these two drive walls 75 to deform so as to protrude toward the non-ejection channel 72. That is, since the actuator plates 61, 101 of this embodiment are made up of two laminated piezoelectric substrates that are polarized in the thickness direction (Y direction), applying a drive voltage causes the drive walls 75 to bend and deform in a V-shape around the midpoint in the Y direction. This causes the ejection channel 71 to deform as if it were bulging.

[0079] When the volume of the ejection channel 71 increases due to the deformation of the two drive walls 75, the ink in the common ink chamber 80 is guided into the ejection channel 71 through the slit 81. The ink guided into the ejection channel 71 then becomes a pressure wave that propagates into the ejection channel 71, and when this pressure wave reaches the nozzle holes 131 and 132, the drive voltage applied between the electrodes 87 and 91 is set to zero. As a result, the driving wall 75 returns to its original state, and the volume of the ejection channel 71, which had temporarily increased, returns to its original volume. This action increases the pressure inside the ejection channel 71, pressurizing the ink. As a result, ink can be ejected from the nozzle holes 131 and 132. At this time, the ink is ejected as liquid ink droplets as it passes through the nozzle holes 131 and 132. This makes it possible to record characters, images, etc. on the recording medium P, as described above. That is, in the head chip 50 of this embodiment, a portion of the ink flowing through each of the communication paths 110 and 111 is ejected through the nozzle holes 131 and 132, while the remaining ink is returned to the manifold 123 through the connection paths 121 and 122.

[0080] [Method for manufacturing head chip 50] Next, a method for manufacturing the above-mentioned head chip 50 will be described. Fig. 11 is a flowchart illustrating the method for manufacturing head chip 50. Figs. 12 to 25 are process diagrams illustrating the method for manufacturing head chip 50. In this case, among Figs. 12 to 21, Figs. 12 to 14 and 17 to 19 are cross-sectional views corresponding to Fig. 10, Figs. 15, 16, and 20 are cross-sectional views corresponding to Fig. 7, and Fig. 21 is a cross-sectional view corresponding to Fig. 6. Among Figs. 12 to 21, Figs. 23 to 25 are cross-sectional views corresponding to Fig. 4. In the following explanation, for convenience, an example in which head chip 50 is manufactured at the chip level will be described.

[0081] As shown in FIG. 11, the head chip 50 includes a module fabrication process S1, a module stacking process S2, a feedback plate stacking process S3, a feedback plate processing process S4, a protective film formation process S5, and a nozzle plate stacking process S6.

[0082] The module fabrication process S1 fabricates a first chip module 51A and a second chip module 51B. The module fabrication process S1 includes a surface pattern formation process S11, a channel formation process S12, a first wiring formation process S13, a dividing groove formation process S14, a cover plate lamination process S15, a grinding process S16, a second wiring formation process (drive wiring formation process) S17, a back plate lamination process S18, and a back plate processing process S19. The chip modules 51A and 51B are fabricated using the same method. Therefore, the following description of the module fabrication process S1 will be given using the first chip module 51A as an example.

[0083] 12, in the surface pattern forming step S11, a mask pattern 200 is formed on the surface of the first actuator plate 61. Specifically, after a mask material (e.g., a resist film) is formed on the surface of the first actuator plate 61, the mask material is patterned using photolithography. In the mask pattern 200, mask openings are formed in portions of the surface of the first actuator plate 61 that correspond to the formation regions of the common terminals 88 and the individual terminals 92, for example.

[0084] 13, in the channel forming step S12, a dicer is used to process the formation regions of the ejection channels 71 and the non-ejection channels 72 in the first actuator plate 61. The amount of penetration of the dicer in the Y direction is set to such an extent that neither the ejection channels 71 nor the non-ejection channels 72 penetrate the first actuator plate 61 after the channel forming step S12.

[0085] 14, in the first wiring formation process S13, oblique deposition or the like is performed from the front surface side of the first actuator plate 61. Specifically, an electrode material is deposited on the front surface of the first actuator plate 61 via a mask pattern 200. As a result, a common terminal 88 and individual terminals 92 are formed on the front surface of the first actuator plate 61.

[0086] In the first wiring formation process S13, an electrode material is introduced into each of the channels 71, 72 through the front-side opening of each of the channels 71, 72. As a result, a part of the common electrode 87 (front-side common portion 87a) is formed on the inner surface of the ejection channel 71 over a predetermined range in the Y direction from the edge of the front-side opening of the ejection channel 71. Meanwhile, on the inner surface of the non-ejection channel 72, a part of the individual electrode 91 (front-side individual portion 91a) is formed over a predetermined range in the Y direction from the edge of the front-side opening of the non-ejection channel 72 facing the ejection channel 71 in the X direction. As shown in FIG. 15, on the inner surface of the non-ejection channel 72, a part of the lead wiring 93 (first wiring portion 95) is formed in a portion located on the +Z side of the individual electrode 91.

[0087] 16, in the dividing groove forming process S14, a dividing groove 79 is formed in the tail portion 76 in a portion located between the common terminal 88 and the individual terminal 92. Specifically, a dicer is run in the X direction on the surface of the first actuator plate 61 in a portion located between the common terminal 88 and the individual terminal 92. As a result, a portion of the lead-out wiring 93 located on the running path of the dicer is removed in conjunction with the processing of the dividing groove 79. That is, on the inner surface of the non-ejection channel 72, a second region 95b having a width narrower than the first region 95a and the third region 95c remains in a portion located on the -Y side of the dividing groove 79. After the dividing groove forming process S14, the mask pattern 200 is removed.

[0088] As shown in FIG. 17, in the cover plate laminating step S15, a first cover plate 62 is attached to the surface of a first actuator plate 61. 18, in the grinding step S16, grinding is performed on the rear surface of the first actuator plate 61. Specifically, the first actuator plate 61 is ground until the ejection channels 71 and the non-ejection channels 72 are opened on the rear surface of the first actuator plate 61.

[0089] As shown in FIG. 19 , in the second wiring formation process S17, oblique deposition or the like is performed from the back surface of the first actuator plate 61 with a mask material 201 set on the back surface of the first actuator plate 61. The mask material 201 has mask openings 201a in the portions of the back surface of the first actuator plate 61 where the channel array 70 is formed when viewed from the Y direction. An electrode material is introduced into the portions of each channel 71, 72 that are exposed through the mask openings 201a through the back surface openings of each channel 71, 72. As a result, a common electrode 87 (back surface common portion 87b) is formed on the inner surface of the ejection channel 71 over a predetermined range in the Y direction from the edge of the back surface opening of the ejection channel 71. As a result, the common electrode 87 is formed over the entire inner surface of the ejection channel 71 in the Y direction.

[0090] In the second wiring formation process S17, individual electrodes 91 (rear-side individual portions 91b) are formed on the inner surfaces of the non-ejection channels 72 over a predetermined range in the Y direction from the rear-side opening edge of the non-ejection channels 72. As a result, the individual electrodes 91 are formed on the inner surfaces of the non-ejection channels 72 over the entire area in the Y direction. 20, a part of the lead wiring 93 (second wiring portion 96) is formed on the inner surface of the non-ejection channel 72 in a portion located on the +Z side of the individual electrode 91. Specifically, an electrode material is introduced into the non-ejection channel 72 through a portion of the non-ejection channel 72 that is exposed through the mask opening 201a when viewed from the Y direction. As a result, the second wiring portion 96 is formed on the inner surface of the non-ejection channel 72 so as to be continuous with the second region 95b. The electrode material is also attached to a portion of the back surface of the actuator plate 61 that is exposed through the mask opening 201a. As a result, a bypass wiring 94 is formed on a portion of the back surface of the actuator plate 61 that faces the dividing groove 79. Note that unnecessary electrode material attached to the portion of the back surface of the first actuator plate 61 that is exposed through the mask opening 201a is removed by laser processing or the like.

[0091] 21, the electrode material is not introduced into the portion of the non-ejection channel 72 that is covered with the mask material 201. As a result, the second wiring portion 96 is formed only in a portion of the lead-out wiring 93, including the second region 95b. Note that the above-mentioned dividing groove forming step S14 may be performed after the second wiring forming step S17.

[0092] As shown in FIG. 22, in the backplate lamination step S18, a first backplate 63 is attached to the rear surface of the first actuator plate 61. In the backplate processing step S19, the first connection path 121 and the first recess 123a are formed in the first backplate 63. This completes the first chip module 51A. Note that the second actuator plate 101 and the like are also fabricated in the same manner as in the module fabrication step S1 described above, to fabricate the second chip module 51B.

[0093] 23, in the module stacking process S2, the chip modules 51A and 51B created in the module creation process S1 are bonded together. Specifically, with the bottom end surfaces of the chip modules 51A and 51B aligned, the back surfaces of the back plates 63 and 103 are bonded together. As a result, the back surface opening of the first connection path 121 is blocked by the second back plate 103, the back surface opening of the second connection path 122 is blocked by the first back plate 63, and the manifold 123 is formed by the first recess 123a and the second recess 123b. This forms a stack of the chip modules 51A and 51B.

[0094] As shown in FIG. 24, in the feedback plate laminating step S3, the feedback plate 52 is attached to the lower end surface of the stack of chip modules 51A and 51B. 25, in the feedback plate processing step S4, communicating paths 110, 111 are formed in the portions of the feedback plate 52 that overlap with the ejection channels 71 in a plan view. The communicating paths 110, 111 are formed by, for example, laser processing the feedback plate 52. Note that the feedback plate processing step S4 may be performed by etching or the like in addition to laser processing. Also, in this embodiment, the communicating paths 110, 111 are formed after the feedback plate 52 is bonded to the chip modules 51A, 51B, but this configuration is not limiting. The communicating paths 110, 111 may be formed in advance in the feedback plate 52 by laser processing, etching, or the like, and then the feedback plate 52 is bonded to the chip modules 51A, 51B.

[0095] In the protective film forming process S5, a protective film 125 is formed on the inner surface of the common ink chamber 80, the inner surface of the slit 81, the inner surface of the ejection channel 71, the inner surface of each communication path 110, 111, the inner surface of each connection path 121, 122, and the inner surface of the manifold 123. The protective film 125 is formed by depositing a film of a paraxylylene-based resin material using, for example, chemical vapor deposition (CVD) or the like.

[0096] In the nozzle plate laminating step S6, the nozzle plate 53 is attached to the lower surface of the feedback plate 52. The head chip 50 is thus completed. When the head chip 50 is manufactured at the wafer level, the actuator plate wafer, the cover plate wafer, and the back plate wafer are subjected to the same process as the module creation process S1 described above to form a wafer stack. The wafer stack is then diced into individual pieces, thereby extracting multiple chip modules 51A, 51B. The chip modules 51A, 51B extracted from the wafer stack are then subjected to the module stacking process S2 and subsequent processes, thereby completing the head chip 50.

[0097] As described above, the head chip 50 according to the first embodiment includes actuator plates (chip bodies) 61, 101 each having an ejection channel (pressure chamber, ejection channel) 71 for storing ink and a drive wall (drive section) 75 arranged in a portion facing the ejection channel 71, individual electrodes (drive electrodes) 91 formed on the drive wall 75, and lead wiring (drive wiring) 93 connecting the individual electrodes 91 and a flexible printed circuit board (external wiring). The lead wiring 93 includes a first wiring section 95 having a first region 95a and a second region 95b whose cross-sectional area perpendicular to the extension direction (Z direction) of the lead wiring 93 is smaller than that of the first region 95a, and a second wiring section 96 connected to at least the second region 95b. According to this configuration, by forming second wiring portion 96 of lead wiring 93 so as to be continuous with at least second region 95b of first wiring portion 95, which has a smaller cross-sectional area than first region 95a, it is possible to reduce the maximum resistance value of lead wiring 93 as a whole. This makes it possible to prevent breakage of lead wiring 93 even if an unexpectedly large current flows through lead wiring 93. As a result, it is possible to provide head chip 50 that has excellent reliability over a long period of time.

[0098] In the head chip 50 according to the first embodiment, the second wiring portion 96 is provided only in a part of the lead wiring 93, including the second region 95b. According to this configuration, the second wiring portion 96 is provided only in a portion of the routing wiring 93 that includes the second region 95b, and therefore the increase in material costs of the routing wiring 93 that accompanies the addition of the second wiring portion 96 can be suppressed compared to when the second wiring portion 96 is formed to cover the entire first wiring portion 95.

[0099] In the head chip 50 according to the first embodiment, the second wiring portion 96 is configured to be integrally connected to at least the second region 95b in the Y direction (second direction) along the inner surface (the film formation surface of the drive wiring) of the non-ejection channel 72 in a planar view. According to this configuration, the risk of wire breakage and the like can be further reduced by connecting the second wiring portion 96 to the second region 95b in a direction along the inner surface of the non-ejection channel 72. In particular, by ensuring the width dimension of the lead-out wiring 93 as in the head chip 50 according to the first embodiment, the risk of film formation defects due to adhesion of foreign matter can be reduced compared to when the thickness of the lead-out wiring 93 is ensured with the same cross-sectional area.

[0100] In the head chip 50 according to the first embodiment, an ejection channel (pressure chamber, ejection channel) 71 and a non-ejection channel (non-ejection channel) 72 are formed in the actuator plate 61, 101, and the drive electrode comprises a common electrode 87 formed on the inner surface of the ejection channel 71 over the entire area in the Y direction, and an individual electrode 91 formed on the inner surface of the non-ejection channel 72 over the entire area in the Y direction, and the routing wiring 93 is connected to the individual electrode 91 on the inner surface of the non-ejection channel 72. According to this configuration, in the actuator plates 61, 101 made up of two piezoelectric substrates with different polarization directions, it is necessary to form the individual electrodes 91 over the entire area in the Y direction on the inner surfaces of the non-ejection channels 72. Therefore, by forming the lead wiring 93 on the inner surfaces of the non-ejection channels 72, it is possible to expand the lead wiring 93 in the Y direction by the second wiring portion 96 when forming the individual electrodes 91 (rear-surface-side individual portions 91b). This eliminates the need to provide a separate wiring formation process for forming the second wiring portion 96, and therefore reduces a decrease in manufacturing efficiency due to the formation of the second wiring portion 96.

[0101] In the head chip 50 of the first embodiment, a separating groove 79 is formed on the surface of the actuator plate 61, 101 to separate the common terminal 88 and the individual terminal 92, and the second region 95b is configured to be located on the inner surface of the non-ejection channel 72 in a portion that overlaps with the separating groove 79 in the Z direction. According to this configuration, the second wiring portion 96 is formed in the portion that overlaps the dividing groove 79 in the Z direction, thereby suppressing short circuits between the common terminal 88 and the individual terminal 92 and reducing the maximum resistance value for the entire routing wiring 93.

[0102] The inkjet head 5 and printer 1 according to the first embodiment include the head chip 50 described above, and therefore, it is possible to provide an inkjet head 5 and printer 1 that are highly reliable.

[0103] (Second embodiment) Fig. 26 is a cross-sectional view of head chip 50 according to the second embodiment, corresponding to Fig. 5. Fig. 27 is a cross-sectional view of a portion of head chip 50 according to the second embodiment, corresponding to Fig. 7. As shown in FIGS. 26 and 27 , the second wiring portion 96 is formed in the Z direction, similarly to the first embodiment, to include the entire second region 95b and straddle the boundary portion of the first region 95a with the second region 95b and the boundary portion of the third region 95c with the second region 95b. Meanwhile, in the Y direction, the entire second wiring portion 96 is disposed to overlap the first wiring portion 95. Therefore, the region of the lead-out wiring 93 where the first wiring portion 95 and the second wiring portion 96 overlap is thicker than the region where only the first wiring portion 95 is formed. In this case, the cross-sectional area of ​​the lead-out wiring 93 in a direction perpendicular to the Z direction is set to be larger than the cross-sectional area of ​​the second region 95b alone at any point in the Z direction. That is, the electrical resistance of the lead-out wiring 93 is smaller than the electrical resistance of the second region 95b alone at any point in the Z direction.

[0104] The second wiring portion 96 can be formed, for example, after the first wiring formation process S13, by setting a mask material on the surface of the actuator plate 61, 101 with only the area where the second wiring portion 96 is to be formed being open, and then performing oblique deposition again from the surface side of the actuator plate 61, 101.

[0105] In the head chip 50 according to the second embodiment, the second wiring portion 96 is configured to cover at least the second region 95b in the X direction perpendicular to the inner surface (film formation surface) of the non-ejection channel 72 in a plan view. According to this configuration, the second wiring portion 96 is provided so as to cover the second region 95b, which makes it possible to suppress an increase in size of the lead wiring 93 in the Y direction (the direction along the film formation surface) that would otherwise be caused by the addition of the second wiring portion 96. This makes it possible to reduce the maximum resistance value of the entire lead wiring 93 while suppressing an increase in capacitance.

[0106] As shown in Figures 28 and 29, a portion of the second wiring portion 96 may overlap the entire first wiring portion 95 in the Y direction, and the remaining second wiring portion 96 may extend beyond the -Y side relative to the first wiring portion 95.

[0107] (Other variations) The technical scope of the present disclosure is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present disclosure. For example, in the above-described embodiment, the inkjet printer 1 has been described as an example of a liquid jet recording apparatus, but the liquid jet recording apparatus is not limited to a printer. For example, a fax machine, an on-demand printer, etc. may also be used. In the above-described embodiment, a configuration in which the inkjet head moves relative to the recording medium during printing (a so-called shuttle machine) has been described as an example, but the present disclosure is not limited to this configuration. The configuration according to the present disclosure may also be employed in a configuration in which the inkjet head is fixed and the recording medium moves relative to the inkjet head (a so-called fixed head machine). In the above-described embodiment, the recording medium P is paper, but this is not limiting. The recording medium P is not limited to paper, and may be a metal material, a resin material, or a food product. In the above-described embodiment, a configuration in which the liquid jet head is mounted on a liquid jet recording apparatus has been described, but the present invention is not limited to this configuration. That is, the liquid jetted from the liquid jet head is not limited to the liquid that lands on a recording medium, but may be, for example, a medicinal liquid to be mixed into a medicine, a food additive such as a seasoning or flavoring to be added to food, or an aromatic to be sprayed into the air.

[0108] In the above-described embodiment, the Z direction is aligned with the direction of gravity, but the present invention is not limited to this configuration, and the Z direction may be aligned with the horizontal direction. In the above-described embodiment, a configuration has been described in which ink is ejected by deforming the actuator plate in a direction that expands the volume of the ejection channel by applying a voltage and then restoring the actuator plate to its original shape (so-called pull ejection), but this configuration is not limited to this. The head chip according to the present disclosure may also be configured to eject ink by deforming the actuator plate in a direction that reduces the volume of the ejection channel by applying a voltage (so-called push ejection). When push ejection is performed, the actuator plate is deformed by applying a drive voltage so as to bulge toward the inside of the ejection channel. This reduces the volume within the ejection channel, increasing the pressure within the ejection channel, and ink within the ejection channel is ejected to the outside through the nozzle hole. When the drive voltage is reduced to zero, the actuator plate is restored to its original shape. As a result, the volume within the ejection channel returns to its original shape.

[0109] In the above embodiment, the configuration in which the chip modules 51A and 51B are stacked has been described, but the configuration is not limited to this. The head chip 50 may be configured with only the first chip module 51A. In the above-described embodiment, an edge chute type head chip has been described as an example, but the present disclosure is not limited to this configuration. For example, the present disclosure may be applied to a so-called side chute type head chip 50 that ejects ink from the center of the ejection channel 71 in the extension direction. The head chip may also be a so-called roof chute type head chip, in which the direction of pressure applied to the ink and the direction of ink ejection are the same. In the case of a roof chute type head chip, the part facing the pressure chamber that contains the ink and that deforms to expand or contract the pressure chamber functions as the drive unit.

[0110] In the above-described embodiment, the second wiring portion 96 overlaps the second region 95b when viewed from the thickness direction (X direction), but the present invention is not limited to this configuration. It is sufficient that the second region 95b and the second wiring portion 96 are at least electrically connected to each other. In this case, for example, the rear-surface-side edge of the second region 95b and the front-surface-side edge of the second wiring portion 96 may simply be connected in the Y direction without overlapping each other when viewed from the X direction.

[0111] In the above-described embodiment, the second wiring portion 96 is formed in a partial region of the first wiring portion 95, including the second region 95b, but the present invention is not limited to this configuration. The second wiring portion 96 may overlap with each other over the entire first wiring portion 95 in the Z direction. In the above-described embodiment, the portion of the lead-out wiring 93 where the dividing groove 79 is formed is defined as the second region 95b, and the second wiring portion 96 is additionally formed in the second region 95b, but this is not the only possible configuration. For example, the second wiring portion may be additionally formed in a portion (second region) where electrical resistance is likely to be large in the drive wiring that connects the common electrode 87 or the individual electrodes 91 to the external wiring, such as the common terminal 88 or the individual terminal 92. In the above-described embodiment, a configuration including a first wiring forming process S13 and a second wiring forming process S17 was described, but a configuration in which the second wiring forming process S17 is performed on an actuator plate on which a first wiring portion 95 has already been formed may also be used.

[0112] In addition, within the scope of the present disclosure, the components in the above-described embodiments may be replaced with well-known components as appropriate, and the above-described modified examples may be combined as appropriate. [Explanation of symbols]

[0113] 1: Printer (liquid jet recording device) 5: Inkjet head (liquid jet head) 50: Head chip 61: First actuator plate (chip body, actuator plate) 71: Discharge channel (pressure chamber, injection channel) 72: Non-ejection channel (non-injection channel) 75: Drive wall (drive part) 79: Dividing trench 87: Common electrode (drive electrode) 88: Common terminal 91: Individual electrode (drive electrode) 92: Individual terminal 93: Pulling wiring (drive wiring) 95: 1st wiring section 95a:First area 95b:Second area 96:Second wiring section 101: Second actuator plate (chip body, actuator plate)

Claims

1. a chip body having a pressure chamber in which a liquid is contained and a drive unit disposed in a portion facing the pressure chamber; a driving electrode formed on the driving portion; a driving wiring formed on the chip body and connecting the driving electrode and an external wiring; The drive wiring is a first wiring portion including a first region and a second region connected to the first region in the extension direction of the drive wiring and having a cross-sectional area perpendicular to the extension direction smaller than that of the first region; a second wiring portion extending in a direction intersecting the extending direction with respect to at least the second region.

2. The head chip according to claim 1 , wherein the second wiring portion is provided only in a portion of the drive wiring that includes the second region.

3. The head chip according to claim 1 or claim 2, wherein the second wiring portion is arranged to cover at least the second region in a first direction perpendicular to the film formation surface of the drive wiring in the chip body when viewed from the extension direction.

4. A head chip as described in claim 1 or claim 2, wherein the second wiring portion is arranged so as to be integrally connected to at least the second region in a second direction along the film formation surface of the drive wiring in the chip body when viewed from the extension direction.

5. the chip body includes an actuator plate formed by stacking two piezoelectric substrates, the polarization directions of which are different in the second direction, in the second direction; The actuator plate includes: an ejection channel as the pressure chamber in which a liquid is contained; a non-ejection channel adjacent to the ejection channel and not containing liquid; the driving portion is configured by a portion of the actuator plate located between the ejection channel and the non-ejection channel, The drive electrode is a common electrode formed over the entire area in the second direction on a portion of the driving unit facing the ejection channel; an individual electrode formed over the entire area in the second direction in a portion of the drive unit facing the non-ejection channel, The head chip according to claim 4 , wherein the drive wiring is connected to the individual electrode at a portion of the drive section that faces the non-ejection channel.

6. a common terminal connecting the common electrode and the external wiring, and a dividing groove separating individual terminals connecting the individual electrodes and the external wiring are formed on a surface of the actuator plate; The head chip according to claim 5 , wherein the second region is located in a portion of the driving section facing the non-ejection channel and overlapping with the dividing groove in the extending direction.

7. A liquid jet head comprising the head chip according to claim 1 or 2.

8. A liquid jet recording apparatus comprising the liquid jet head according to claim 7.

9. a drive wiring forming step of forming drive wiring on a chip body having a pressure chamber in which a liquid is stored and a drive section on which a drive electrode is formed, the drive wiring connecting the drive electrode and an external wire, the drive wiring being disposed in a portion facing the pressure chamber; The drive wiring forming process is a method for manufacturing a head chip in which a first wiring portion is formed in the chip body, the first wiring portion having a first region and a second region that is connected to the first region in the extension direction of the drive wiring and has a cross-sectional area perpendicular to the extension direction that is smaller than that of the first region, and a second wiring portion is formed so that the second wiring portion is connected to at least the second region in a direction intersecting the extension direction.

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