Head tip, liquid injection head, and liquid injection recording device

Abstract

The present invention provides a head chip, a liquid injection head, and a liquid injection recording device that can improve manufacturing efficiency and yield. [Solution] A head tip according to one aspect of the present disclosure includes an actuator portion having a first groove that opens on a first surface facing the injection hole plate in a first direction and is provided for each pressure chamber, and a second groove that opens on a second surface facing away from the injection hole plate in a first direction and is aligned in a second direction with respect to the first groove, and a frame portion that has an opening formed on the side of the actuator portion away from the injection hole plate that exposes at least a part of the second groove and surrounds the first groove and the second groove when viewed from the first direction. The actuator portion includes a first electrode formed on the inner surface of the first groove and a second electrode formed on the inner surface of the second groove that generates an electric field in the actuator portion by creating a potential difference between itself and the first electrode.

Description

Technical Field

[0001] The present disclosure relates to a head chip, a liquid ejection head, and a liquid ejection recording apparatus.

Background Art

[0002] A head chip mounted on an inkjet printer causes pressure fluctuations in a pressure chamber to eject the ink filled in the pressure chamber through nozzle holes. As this type of head chip, a configuration including an actuator plate facing the pressure chamber, a nozzle plate in which nozzle holes are formed, and a cover plate laminated on the opposite side of the nozzle plate with respect to the actuator plate is known.

[0003] For example, in Patent Document 1 below, drive electrodes that generate an electric field in the actuator plate are formed on both surfaces of the actuator plate. The drive electrodes are connected to pads formed on the upper surface of the cover plate through through-wiring that penetrates the cover plate.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] By the way, in the above prior art, the entire upper surface of the actuator plate is covered with the cover plate. Therefore, in the inspection process after laminating the cover plate, when a film formation defect is detected in the drive electrode formed on the upper surface of the actuator plate, it is difficult to perform rework. As a result, it has been difficult to improve the yield. On the other hand, if a cover plate is not used, the rigidity of the head chip decreases, which reduces the handling of the head chip during manufacturing. As a result, there is a problem that leads to a decrease in manufacturing efficiency.

[0006] This disclosure provides a head chip, a liquid injection head, and a liquid injection recording device that can improve manufacturing efficiency and yield. [Means for solving the problem]

[0007] To address the above issues, this disclosure adopts the following characteristics. (1) A head tip according to one aspect of the present disclosure comprises: an injection hole plate having a plurality of injection holes penetrating in a first direction, arranged in a second direction intersecting the first direction; and a tip body provided facing the injection hole plate in the first direction such that a plurality of pressure chambers communicating with each of the plurality of injection holes are formed between the tip body and the injection hole plate, wherein the tip body comprises: an actuator portion having a first groove opening on a first surface facing the injection hole plate in the first direction and provided for each of the pressure chambers, and a second groove opening on a second surface facing the opposite side of the injection hole plate in the first direction and arranged in the second direction relative to the first groove; and a frame portion having an opening on the side of the actuator portion opposite to the injection hole plate that exposes at least a part of the second groove, and surrounding the first groove and the second groove when viewed from the first direction, wherein the actuator portion comprises: a first electrode formed on the inner surface of the first groove; and a second electrode formed on the inner surface of the second groove that generates an electric field in the actuator portion by creating a potential difference between itself and the first electrode.

[0008] According to this embodiment, the first groove and the second groove are opened separately on the first and second surfaces of the chip body, and the frame portion is provided on the side opposite to the injection hole plate relative to the actuator portion, making it easier to ensure the rigidity of the chip body. This improves handling during manufacturing and increases manufacturing efficiency. Furthermore, in this embodiment, electrode material can be introduced into the frame through the opening. This makes it easier to inspect the second electrode through the opening after its formation. As a result, yield can be improved, for example, by allowing rework in the event of a film deposition defect.

[0009] (2) In the head tip according to the embodiment of (1) above, it is preferable that the frame portion surrounds all of the first grooves and the second grooves when viewed from the first direction. According to this embodiment, since no frame is placed between adjacent second grooves, it is possible to suppress the obstruction of the electrode material by the frame when forming the second electrode through the opening. As a result, the second electrode can be deposited in the second groove with high precision, and the yield can be improved.

[0010] (3) In a head chip according to the embodiment of (1) or (2) above, it is preferable that the chip body comprises an actuator plate constituting the actuator portion and a support plate constituting the frame portion and laminated on the actuator plate. According to this embodiment, the support plates can be stacked after the second groove is formed, thereby improving machinability.

[0011] (4) In the head tip according to the embodiment of (3) above, it is preferable that a part of the second groove overlaps with the frame portion when viewed from the first direction. According to this embodiment, it becomes easier to secure the dimensions of the second groove compared to the case where the second groove is contained within the frame. This makes it easier to secure the area of ​​the second electrode and improve the pressure generated in the pressure chamber during liquid injection.

[0012] (5) In the head chip according to the embodiment of (1) or (2) above, it is preferable that the chip body is configured such that the actuator portion and the frame portion are integrally formed. According to this embodiment, the number of parts can be reduced, and the joining process between the actuator and the frame can be omitted. This improves manufacturing efficiency and reduces costs. Furthermore, since no adhesive is interposed between the actuator and the frame, it is possible to suppress issues such as the conduction of drive wiring being hindered by adhesive.

[0013] (6) In a head chip according to any of the embodiments of (1) to (5) above, it is preferable that the frame portion is formed with a first pad connected to the first electrode and on which external wiring is mounted, and a second pad connected to the second electrode and on which the external wiring is mounted. According to this embodiment, the portion where the actuator and frame overlap is the part of the chip body that has a large dimension in the first direction and high rigidity. Therefore, by forming the first pad and the second pad on the frame, it can withstand the load when mounting external wiring. Furthermore, in this embodiment, since the second groove is opened through the opening as described above, each pad and the second electrode can be deposited simultaneously in the film deposition process. This reduces manufacturing man-hours and lowers costs.

[0014] (7) In the head chip according to the embodiment of (6) above, the first pad and the second pad are formed on the surface of the frame portion facing away from the actuator portion in the first direction, and the portion of the inner circumferential surface of the opening located between the second electrode and the second pad is formed as an inclined surface that is inclined in a direction in which the dimensions of the opening increase as it approaches the surface in the first direction, and it is preferable that wiring connecting the second electrode and the second pad is formed on the inclined surface. According to this embodiment, by forming an inclined surface on the inner circumferential surface of the opening, specifically the portion located between the second electrode and the second pad, it becomes easier to form routing wires during the film deposition process. This ensures the reliability of conductivity and improves yield.

[0015] (8) In a head chip according to any of the embodiments of (1) to (7) above, it is preferable that the actuator portion is set with the first direction as the polarization direction, and a third electrode is formed on the second surface of the actuator portion at a position facing the first electrode in the first direction, which generates an electric field in the actuator portion by creating a potential difference between it and the first electrode. According to this embodiment, an electric field can be generated in the first direction (polarization direction) of the actuator. This allows the actuator to be deformed in the first direction in bend mode (unimorph type). This makes it possible to further improve the generated pressure.

[0016] (9) In a head chip according to any of the embodiments of (1) to (8) above, it is preferable that the actuator portion protrudes in the first direction from the portion of the first surface located between adjacent first grooves in the second direction, and also includes a partition portion that separates adjacent pressure chambers. According to this embodiment, since the first surface is positioned away from the injection hole plate, the actuator can be smoothly deformed when an electric field is generated in the actuator. This ensures a sufficient amount of deformation in the actuator and makes it easier to improve the pressure generated in the pressure chamber during liquid injection.

[0017] (10) A liquid spray head according to one aspect of the present disclosure comprises a head tip according to any of the aspects described in (1) to (9) above. According to this embodiment, it is possible to improve manufacturing efficiency and yield.

[0018] (11) A liquid injection recording device according to one aspect of the present disclosure is equipped with a liquid injection head according to the aspect of (10) above. According to this embodiment, it is possible to improve manufacturing efficiency and yield. [Effects of the Invention]

[0019] According to one aspect of this disclosure, it is possible to improve manufacturing efficiency and yield.

Brief Description of the Drawings

[0020] [Figure 1] It is a schematic configuration diagram of an inkjet printer 1 according to the first embodiment. [Figure 2] It is a schematic configuration diagram of an inkjet head 5 and an ink circulation mechanism 6 according to the first embodiment. [Figure 3] It is an exploded perspective view of a discharge unit 30 according to the first embodiment. [Figure 4] It is an exploded perspective view of a head chip 32 according to the first embodiment. [Figure 5] It is a cross-sectional view of the head chip 32 corresponding to the V-V line in FIG. 4. [Figure 6] It is a cross-sectional view of the discharge unit 30 corresponding to the VI-VI line in FIG. 5. [Figure 7] It is a cross-sectional view of the discharge unit 30 corresponding to the VII-VII line in FIG. 5. [Figure 8] It is a plan view of the head chip 32 according to the first embodiment. [Figure 9] It is a cross-sectional view corresponding to the IX-IX line in FIG. 6. [Figure 10] It is a flowchart for explaining a manufacturing method of a discharge unit according to the first embodiment. [Figure 11] It is a process diagram for explaining a support plate processing step S11, and is a cross-sectional view corresponding to FIG. 6. [Figure 12] It is a process diagram for explaining a support plate processing step S11, and is a cross-sectional view corresponding to FIG. 6. [[ID=4I]] [Figure 13] It is a process diagram for explaining an actuator first processing step S12, and is a cross-sectional view corresponding to FIG. 7. [Figure 14] It is a process diagram for explaining a first bonding step S13, and is a cross-sectional view corresponding to FIG. 7. [Figure 15] It is a process diagram for explaining a first film formation step S14, and is a cross-sectional view corresponding to FIG. 7. [Figure 16]This is a process diagram illustrating the second actuator machining process S15, and is a cross-sectional view corresponding to Figure 6. [Figure 17] This is a process diagram illustrating the second actuator machining process S15, and is a cross-sectional view corresponding to Figure 6. [Figure 18] This is a process diagram illustrating the second actuator machining process S15, and is a cross-sectional view corresponding to Figure 6. [Figure 19] This is a process diagram illustrating the second film deposition process S16, and is a cross-sectional view corresponding to Figure 6. [Figure 20] This is a cross-sectional view of the discharge unit 30 according to the second embodiment, and is a cross-sectional view corresponding to Figure 8. [Figure 21] This is a plan view of the discharge unit 30 according to the third embodiment, corresponding to Figure 8. [Figure 22] This is a cross-sectional view of the discharge unit 30 according to the third embodiment, corresponding to Figure 6. [Figure 23] This is a cross-sectional view of the discharge unit 30 according to the third embodiment, corresponding to Figure 7. [Figure 24] This is a cross-sectional view of the discharge unit 30 according to the fourth embodiment, corresponding to Figure 6. [Figure 25] This is a cross-sectional view of the discharge unit 30 according to the fourth embodiment, corresponding to Figure 7. [Figure 26] This is a cross-sectional view corresponding to the line XXVI-XXVI in Figure 24. [Modes for carrying out the invention]

[0021] Embodiments relating to this disclosure will be described below with reference to the drawings. In the embodiments and modifications described below, corresponding components may be denoted by the same reference numerals and their descriptions omitted. In the following description, expressions indicating relative or absolute arrangements such as "parallel," "orthogonal," "center," and "coaxial" will not only strictly represent such arrangements, but also represent states of relative displacement with tolerances or angles and distances that allow the same function to be obtained. In the following embodiments, an inkjet printer (hereinafter simply referred to as "printer") that uses ink (liquid) to record on a recording medium will be used as an example. In the drawings used in the following description, the scale of each component has been appropriately changed in order to make each component recognizable.

[0022] (First Embodiment) [Printer 1] Figure 1 is a schematic diagram of printer 1. The printer (liquid jet recording device) 1 shown in Figure 1 comprises 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.

[0023] In the following explanation, the Cartesian coordinate system of X, Y, and Z will be used as needed. In this case, the X direction coincides with the transport direction (sub-scanning direction) of the recording medium P (e.g., paper). The Y direction coincides with the scanning direction (main scanning direction) of the scanning mechanism 7. The Z direction represents the height direction (gravity direction) perpendicular to the X and Y directions. In the following explanation, among the X, Y, and Z directions, the side indicated by the arrow in the figure will be considered the positive (+) side, and the side opposite the arrow will be considered the negative (-) side. In this specification, the +Z side corresponds to the upward direction of gravity, and the -Z side corresponds to the downward direction of gravity.

[0024] The transport mechanisms 2 and 3 transport the recording medium P to the +X side. Each of the transport mechanisms 2 and 3 includes, for example, a pair of rollers 11 and 12 extending in the Y direction. Each ink tank 4 contains four separate inks, for example, yellow, magenta, cyan, and black. Each inkjet head 5 is configured to eject the four inks corresponding to the connected ink tank 4.

[0025] Figure 2 is a schematic diagram of the inkjet head 5 and the ink circulation mechanism 6. As shown in Figures 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 channel 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.

[0026] The pressurizing 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 is under positive pressure relative to the inkjet head 5. The suction pump 25 reduces the pressure inside the ink discharge pipe 22 and draws ink from the inkjet head 5 through the ink discharge pipe 22. As a result, there is negative pressure on the ink discharge pipe 22 side relative to the inkjet head 5. The ink can be circulated between the inkjet head 5 and the ink tank 4 through the circulation channel 23, driven by the pressurizing pump 24 and the suction pump 25.

[0027] As shown in Figure 1, the scanning mechanism 7 causes the inkjet head 5 to reciprocate 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.

[0028] <Inkjet head 5> The inkjet head 5 is mounted on a carriage 29. In the illustrated example, multiple inkjet heads 5 are mounted in a row in the Y direction on a single carriage 29. The inkjet head 5 includes an ejection unit 30 (see Figure 2), an ink supply unit (not shown) connecting the ink circulation mechanism 6 and the ejection unit 30, and a control unit (not shown) that applies a drive voltage to the ejection unit 30.

[0029] (First Embodiment) [Discharge unit 30] Figure 3 is an exploded perspective view of the discharge unit 30. The ejection unit 30 shown in Figure 3 is a so-called circulating side-chute type ejection unit 30 that circulates ink between itself and the ink tank 4 and ejects ink from the center of the pressure chamber 50 in the extending direction (Y direction). The ejection unit 30 comprises a flow path frame member 31, a head chip 32, a flow path cover 34, and a flexible printed circuit board 35 (see Figure 7).

[0030] <Flow channel frame member 31> The flow path frame member 31 is formed in a rectangular frame shape with the Z direction as the thickness direction and the X direction as the longitudinal direction. The flow path frame member 31 separates the chip housing section 31a, the inlet common flow path 31b, and the outlet common flow path 31c. The chip housing section 31a, the inlet common flow path 31b, and the outlet common flow path 31c are in communication with each other and penetrate the flow path frame member 31 in the Z direction.

[0031] The chip housing portion 31a is formed in the central part of the flow path frame member 31 in the Y direction. In a plan view, the chip housing portion 31a is formed in the shape of an elongated hole with the X direction as its longitudinal direction. The common inlet channel 31b is formed in the portion of the channel frame member 31 located on the +Y side relative to the chip housing portion 31a. The common inlet channel 31b is formed in the same way as the chip housing portion 31a, with the X direction as its longitudinal direction. The +X side end of the common inlet channel 31b protrudes in the X direction relative to the chip housing portion 31a. The common outlet channel 31c is formed in the portion of the channel frame member 31 located on the -Y side relative to the chip housing portion 31a. The common outlet channel 31c is formed in the same way as the common inlet channel 31b, with the X direction as its longitudinal direction. The -X side end of the common outlet channel 31c protrudes in the X direction relative to the chip housing portion 31a.

[0032] <Head tip 32> Figure 4 is an exploded perspective view of the head chip 32. As shown in Figure 4, the head chip 32 has multiple pressure chambers 50 in the X direction in which ink is contained, and discharges ink from the pressure chambers 50 through nozzle holes 39a that communicate with each pressure chamber 50 individually, depending on the pressure fluctuations within the pressure chambers 50. The head chip 32 comprises a chip module 37 and a nozzle plate 39.

[0033] As shown in Figure 3, the chip module 37 is formed in a block shape with the Z direction as the thickness direction and the X direction as the longitudinal direction. The chip module 37 is fitted into the chip housing portion 31a. Specifically, the chip module 37 has a thickness in the Z direction equivalent to that of the flow path frame member 31, and its plan view shape is equivalent to that of the chip housing portion 31a. In this case, the +X side end face of the chip module 37 is fixed by adhesive or the like to the inner surface of the chip housing portion 31a facing the -X side, and the -X side end face is fixed by adhesive or the like to the inner surface of the chip housing portion 31a facing the +X side. Therefore, within the flow path frame member 31, the inlet common flow path 31b and the outlet common flow path 31c are blocked by the chip module 37.

[0034] Figure 5 is a cross-sectional view of the head tip 32 corresponding to the VV line in Figure 4. Figure 6 is a cross-sectional view of the discharge unit 30 corresponding to the VI-VI line in Figure 5. Figure 7 is a cross-sectional view of the discharge unit 30 corresponding to the VII-VII line in Figure 5. As shown in Figures 5 to 7, the chip module 37 comprises an actuator plate 41 and a support plate 42. The actuator plate 41 and the support plate 42 are stacked in the Z direction. In the following description, the direction from the actuator plate 41 toward the support plate 42 (+Z side) in the Z direction may be referred to as the upper side, and the direction from the support plate 42 toward the actuator plate 41 (-Z side) may be referred to as the lower side. In the first embodiment, the lower surface of the head chip 32 is flush with the lower surface of the flow path frame member 31. On the other hand, the upper surface of the head chip 32 is flush with the upper surface of the flow path frame member 31.

[0035] <Actuator Plate 41> The actuator plate 41 defines at least a portion of the pressure chamber 50 and causes pressure fluctuations in the pressure chamber 50 during ink ejection. The actuator plate 41 is made of a piezoelectric material such as PZT (lead zirconate titanate). For example, the actuator plate 41 uses a so-called monopole substrate in which the polarization direction is unidirectional throughout the entire Z-direction. That is, the actuator plate 41 is integrally formed without any bonding interfaces. Alternatively, the actuator plate 41 may use a so-called chevron substrate, which is made by laminating two piezoelectric plates with different polarization directions in the Z-direction.

[0036] The actuator plate 41 has a plurality of individual flow channels 51 and a plurality of dividing recesses 52 formed therein. Each individual channel 51 is a portion that defines the pressure chamber 50. In this embodiment, the pressure chamber 50 is composed solely of the individual channels 51 formed in the actuator plate 41. However, an intermediate plate may be interposed between the actuator plate 41 and the nozzle plate 39 as a chip module 37. In this case, the pressure chamber 50 may be formed by the individual channels 51 and the channels formed in the intermediate plate.

[0037] The individual channels 51 open on the lower surface of the actuator plate 41 and extend linearly in the Y direction. The individual channels 51 are formed in a stepped shape, with the dimensions in the X direction decreasing as they are located higher up when viewed from the Y direction. Specifically, the individual channels 51 include a main channel 51a and an electrode forming groove 51b.

[0038] The main flow path 51a opens at the lower surface of the actuator plate 41 and extends linearly in the Y direction along the actuator plate 41. The -Y side end of the main flow path 51a is open at the -Y side end face of the actuator plate 41. The +Y side end of the main flow path 51a is located inside the actuator plate 41 (and is not open at the +Y side end face of the actuator plate 41). Each individual flow path 51 communicates with the common outlet flow path 31c through the -Y side end of the main flow path 51a. The portions of the actuator plate 41 located on both sides in the X direction relative to the main flow path 51a constitute a partition 54. The partition 54 separates adjacent pressure chambers 50 in the X direction.

[0039] The electrode forming groove 51b is connected to the main channel 51a at its central portion in the X direction. The electrode forming groove 51b opens at the top surface of the main channel 51a and extends linearly in the Y direction, following the main channel 51a. In the example in Figure 7, the electrode forming groove 51b communicates with the main channel 51a over its entire length in the Y direction. However, it is sufficient for the electrode forming groove 51b to communicate with the main channel 51a in at least a portion of the Y direction.

[0040] As shown in Figures 5 and 7, the dividing recess 52 is formed in the actuator plate 41 between adjacent electrode forming grooves 51b in the X direction. The dividing recess 52 opens on the upper surface of the actuator plate 41 and extends linearly in the Y direction. Therefore, the dividing recess 52 is positioned alternately with the electrode forming grooves 51b in the X direction (shifted relative to each other when viewed from the Z direction) and extends parallel to the electrode forming grooves 51b in a plan view. The ends of the dividing recess 52 in the Y direction are not open to the end faces in the Y direction of the actuator plate 41.

[0041] The portion of the actuator plate 41 located above the partition portion 54 constitutes the opposing portion 55. The opposing portion 55 is formed in a plate shape having a lower surface where the electrode forming groove 51b opens and an upper surface where the dividing recess 52 opens. Therefore, in the region in the Y direction where both the electrode forming groove 51b and the dividing recess 52 are formed (see Figure 5), the opposing portion 55 is formed in a zigzag (wavy) shape that meanders in the Z direction. The opposing portion 55 constitutes the top wall of each pressure chamber 50 (individual flow path 51). The opposing portion 55 is located above all of the pressure chambers 50, straddling the space between each pressure chamber 50. Therefore, the pressure chambers 50 are surrounded by adjacent partition portions 54 and the portion of the opposing portion 55 located between adjacent partition portions 54.

[0042] As shown in Figure 5, at least a portion of the dividing recess 52 overlaps with one of the partition portions 54 in a plan view. In the first embodiment, the dividing recess 52 is located in the X direction, including the center of the partition portion 54 and not in contact with the electrode forming groove 51b. Furthermore, the depth in the Z-direction of the dividing recess 52 and the electrode forming groove 51b is formed to be more than half the thickness in the Z-direction of the opposing portion 55. Therefore, parts of the dividing recess 52 and the electrode forming groove 51b overlap each other when viewed from the X-direction (they overlap in the Z-direction).

[0043] Of the opposing portion 55, the portion located between adjacent electrode-forming grooves 51b and dividing recesses 52 in the X direction constitutes a drive wall 59. In a cross-sectional view perpendicular to the Y direction, the drive wall 59 has the same thickness as the opposing portion 55. Furthermore, the width of the opposing portion 55 in the X direction is narrower than that of the electrode-forming grooves 51b, dividing recesses 52, and side wall portions 54.

[0044] The drive walls 59 are provided at positions corresponding to both ends in the X direction of a single pressure chamber 50. In the following description, the drive wall 59 located at the +X side end of the pressure chamber 50 may be referred to as the +X side drive wall 59a, and the drive wall 59 located at the -X side end of the pressure chamber 50 may be referred to as the -X side drive wall 59b. In the first embodiment, the +X side drive wall 59a of one pressure chamber 50 also functions as the -X side drive wall 59b of the pressure chamber 50 adjacent to the first pressure chamber 50 on the +X side. The -X side drive wall 59b of one pressure chamber 50 also functions as the +X side drive wall 59a of the pressure chamber 50 adjacent to the first pressure chamber 50 on the -X side.

[0045] <Support plate 42> As shown in Figures 4 and 6, the support plate 42 supports the actuator plate 41 from above by being laminated on top of the actuator plate 41. The support plate 42 is a plate-shaped plate formed to have the same planar external shape as the actuator plate 41. The support plate 42 is fixed to the upper surface of the actuator plate 41 (opposing portion 55) by adhesive or the like. In the illustrated example, the thickness of the support plate 42 is greater than that of the actuator plate 41. However, the thickness of the support plate 42 may be thinner than that of the actuator plate 41. The support plate 42 can be made of, for example, metal, metal oxide, glass, resin, ceramics, etc.

[0046] As shown in Figures 5 to 7, the support plate 42 has an opening 42a that exposes the upper surface of the actuator plate 41. The opening 42a penetrates the support plate 42 in the Z direction, excluding the outer peripheral portion. Specifically, the opening 42a is formed in a region that spans all of the pressure chambers 50 in the X direction. Therefore, the opening 42a exposes all of the dividing recesses 52 over the entire X direction. As shown in Figure 7, the opening 42a is formed in a region that excludes both ends of each pressure chamber 50 in the Y direction. Therefore, the opening 42a exposes the regions of the dividing recesses 52 excluding both ends in the Y direction.

[0047] Figure 8 is a plan view of the support plate 42. As shown in Figures 5 to 8, the portion of the support plate 42 that forms the opening 42a (hereinafter referred to as the frame portion 60) surrounds all of the pressure chambers 50 in a plan view. The frame portion 60 comprises a +Y side extending portion 60a and a -Y side extending portion 60b that face each other in the Y direction and extend in the X direction, and a +X side extending portion 60c and a -X side extending portion 60d that face each other in the X direction and connect the ends of the +Y side extending portion 60a and the -Y side extending portion 60b, respectively.

[0048] The +Y-side extension 60a and the -Y-side extension 60b extend in the X direction at a position that overlaps with the outer end in the Y direction of the corresponding dividing recess 52 in a plan view. The inner circumferential surfaces (facing surfaces in the Y direction) of the +Y-side extension 60a and the -Y-side extension 60b are formed as inclined surfaces that extend in a direction that moves away from each other in the Y direction as they extend upward. As shown in Figure 5, the +X-side extension portion 60c and the -X-side extension portion 60d extend in the Y direction from a position that overlaps with the outermost pressure chamber 50 in a plan view, or from a position outside the X direction relative to the outermost pressure chamber 50. The inner circumferential surfaces (facing surfaces in the X direction) of the +X-side extension portion 60c and the -X-side extension portion 60d are formed as inclined surfaces that extend in a direction that moves away from each other in the X direction as they extend upward.

[0049] As shown in Figures 6 and 8, a common recess 65 is formed in the frame portion 60. The common recess 65 extends in the Z direction, opening at the upper surface of the frame portion 60. In the illustrated example, the common recess 65 is formed in the +Y side extending portion 60a of the frame portion 60. Multiple common recesses 65 are provided in the +Y side extending portion 60a, spaced apart in the X direction, corresponding to the pressure chamber 50. The common recess 65 is formed in a tapered shape, with its outer shape decreasing in plan view as it extends downwards.

[0050] Figure 9 is a cross-sectional view corresponding to the IX-IX line in Figure 6. As shown in Figures 6, 7, and 9, the chip module 37 has a connection groove 70 and an inlet passage 71. The connecting groove 70 is formed at the +Y side end of the chip module 37 so as to be connected to each of the electrode forming grooves 51b. Specifically, the connecting groove 70 opens at the top surface of the main flow channel 51a and extends linearly from the electrode forming groove 51b toward the +Y side. The top surface of the connecting groove 70 faces the same direction (-Z side) as the top surface of the electrode forming groove 51b. The +Y side end of the connecting groove 70 is located inside the chip module 37 (it is not open at the +Y side end surface of the chip module 37). The -Y side end of the connecting groove 70 opens into the electrode forming groove 51b. The -Y side end of the connecting groove 70 is formed to gradually deepen toward the +Y side. That is, the bottom surface of the -Y side end of the connecting groove 70 is formed as an inclined surface that curves toward the +Y side and extends upward.

[0051] In the Z direction, the connection groove 70 is formed to span the actuator plate 41 and the support plate 42. The connection groove 70 is formed to be recessed upward relative to each electrode forming groove 51b. In this embodiment, the top surface of the connection groove 70 is located within the support plate 42. That is, the connection groove 70 does not penetrate the chip module 37 in the Z direction. However, the connection groove 70 may penetrate both the actuator plate 41 and the support plate 42 in the Z direction.

[0052] As shown in Figure 9, the width of the connection groove 70 in the X direction is equal to that of the electrode formation groove 51b. In this case, the inner surface of the connection groove 70 faces the same direction (X direction) as the inner surface of the electrode formation groove 51b. However, the width of the connection groove 70 in the X direction can be changed as appropriate.

[0053] As shown in Figures 6, 7, and 9, the inlet passage 71 is formed in the portion of the chip module 37 located on the +Y side relative to the individual channels 51 and connection grooves 70. The inlet passage 71 is open on the +Y side end face and bottom face of the chip module 37. The inlet passage 71 also extends in the X direction in the chip module 37 to connect adjacent individual channels 51 and connection grooves 70 together. The individual channels 51 communicate with the common inlet channel 31b through the inlet passage 71.

[0054] <Nozzle Plate 39> As shown in Figure 6, the nozzle plate 39 covers the lower surfaces of the chip module 37 and the flow path frame member 31 together. The nozzle plate 39 is joined to the lower surfaces of the actuator plate 41 and the flow path frame member 31 via adhesive or the like. As a result, the nozzle plate 39 covers the lower end openings of the inlet common flow path 31b and the outlet common flow path 31c, as well as the lower end opening of the main flow path 51a (pressure chamber 50). The nozzle plate 39 is formed of, for example, a resin material (polyimide, etc.). However, the nozzle plate 39 may be made of a material other than resin, such as a metal material (SUS, Ni-Pd, etc.), glass, or silicon.

[0055] The nozzle plate 39 has multiple nozzle holes 39a formed therein, penetrating the nozzle plate 39 in the Z direction. The nozzle holes 39a are tapered, for example, with the inner diameter gradually decreasing from top to bottom. Each nozzle hole 39a is provided corresponding to each pressure chamber 50, except for the outermost pressure chamber 50. Each nozzle hole 39a is provided in a position that overlaps with each main flow path 51a in a plan view. That is, each nozzle hole 39a is individually connected to the corresponding pressure chamber 50 through the main flow path 51a.

[0056] Next, we will explain the various wirings formed on the head chip 32. The head chip 32 is equipped with common wiring 81 and individual wiring 82 as drive wiring. As shown in Figures 5 to 7, the common wiring 81 includes a common electrode 81a, a routing wiring 81b, a top surface wiring 81c, a through wiring 81d, and a common pad 81e.

[0057] The common electrode 81a is formed on the inner surface of at least each electrode forming groove 51b on the lower surface of the opposing portion 55. In the illustrated example, the common electrode 81a is formed over the entire inner surface of the electrode forming groove 51b. That is, the entire common electrode 81a faces into the pressure chamber 50.

[0058] The routing wiring 81b connects the common electrode 81a and the top surface wiring 81c. The routing wiring 81b is formed on the inner surface of the connection groove 70. In the first embodiment, the routing wiring 81b is formed on the inner surfaces and the top surface of the connection groove 70 that face each other in the X direction. The routing wiring 81b is connected to the common electrode 81a through the lower end opening edge of the connection groove 70.

[0059] The top surface wiring 81c is formed on the inner surface of the entrance passage 71. Specifically, the top surface wiring 81c extends in a strip shape in the X direction on the top surface of the entrance passage 71. The -Y side end of the top surface wiring 81c is connected to the routing wiring 81b.

[0060] As shown in Figures 6 and 9, the through-wiring 81d is for connecting the top surface wiring 81c and the common pad 81e, and is provided so as to penetrate the support plate 42. The through-wiring 81d is formed on the inner surface of the common recess 65. The through-wiring 81d is connected to the top surface wiring 81c at the lower edge of the common recess 65. Note that it is sufficient for the through-wiring 81d to have conductivity along the entire length in the Z direction of the inner surface of the common recess 65. That is, the through-wiring 81d may be formed over the entire circumferential surface of the inner surface of the common recess 65, or it may be formed only on a part of the circumferential surface.

[0061] As shown in Figures 4 and 8, the common pad 81e is formed on the upper surface of the support plate 42. Specifically, the common pad 81e is formed on the upper surface of the +Y side extension portion 60a. The common pad 81e is connected to the through wiring 81d at the upper end opening edge of the common recess 65.

[0062] As shown in Figures 5 to 8, the individual wiring 82 comprises a first individual electrode 82a, a second individual electrode 82b, a third individual electrode 82c, a connecting wire 82d, a routing wire 82e, and an individual pad 82f.

[0063] The first individual electrodes 82a are formed on the upper surface of the opposing portion 55 in a portion that overlaps with each pressure chamber 50 in a plan view through the opening 42a. In the first embodiment, the first individual electrodes 82a are formed on the upper surface of the opposing portion 55 in a portion that overlaps with the electrode forming groove 51b in a plan view through the opening 42a. Therefore, the first individual electrodes 82a face the common electrode 81a in the Z direction with the opposing portion 55 in between.

[0064] The second individual electrode 82b is formed in the portion of the dividing recess 52 (+X side dividing recess 52a) located on the +X side with respect to the pressure chamber 50 that is exposed through the opening 42a. The second individual electrode 82b is formed on the inner surface of the +X side dividing recess 52a, extending from the inner surface facing the +X side to the bottom surface. Therefore, the second individual electrode 82b faces the common electrode 81a across the +X side drive wall 59a.

[0065] The third individual electrode 82c is formed in the portion of the dividing recess 52 (-X side dividing recess 52b) located on the -X side with respect to the pressure chamber 50 that is exposed through the opening 42a. The third individual electrode 82c is formed on the inner surface of the -X side dividing recess 52b, extending from the inner surface facing the -X side to the bottom surface. Therefore, the third individual electrode 82c faces the common electrode 81a across the -X side drive wall 59b. The second individual electrode 82b corresponding to one pressure chamber 50 and the third individual electrode 82c corresponding to another pressure chamber 50 adjacent to one pressure chamber 50 are separated at the bottom surface of the dividing recess 52. Note that the first individual electrode 82a, the second individual electrode 82b, and the third individual electrode 82c corresponding to one pressure chamber 50 may not be separated from each other, but may be formed integrally.

[0066] The connecting wire 82d connects the -Y-side ends of the first individual electrode 82a, the second individual electrode 82b, and the third individual electrode 82c, which are provided corresponding to one pressure chamber 50, in the portion of the upper surface of the opposing portion 55 that is exposed through the opening 42a. The connecting wire 82d is connected to the first individual electrode 82a in the center in the X direction. The connecting wire 82d is connected to the second individual electrode 82b at its +X-side end. The connecting wire 82d is connected to the third individual electrode 82c at its -X-side end.

[0067] The routing wire 82e connects the first individual electrode 82a, the second individual electrode 82b, and the third individual electrode 82c, which are provided on the inner circumferential surface of the +Y side extension portion 60a, corresponding to one pressure chamber 50. The routing wire 82e is connected to the +Y side ends of the corresponding first individual electrode 82a, the second individual electrode 82b, and the third individual electrode 82c at the lower end edge of the inner circumferential surface of the +Y side extension portion 60a. The +Y side ends of the first individual electrode 82a, the second individual electrode 82b, and the third individual electrode 82c, which correspond to one pressure chamber 50, may be connected to the routing wire 82e while being connected to each other on the upper surface of the actuator plate 41.

[0068] As shown in Figures 4 and 9, the individual pads 82f are formed on the upper surface of the support plate 42. Specifically, the individual pads 82f are formed on the upper surface of the +Y side extension portion 60a. The individual pads 82f are connected to the routing wiring 82e at the upper edge of the inner circumferential surface of the +Y side extension portion 60a. A separation groove 85 is formed on the upper surface of the +Y side extension portion 60a in the portion located between the individual pad 82f and the common pad 81e, separating the individual pad 82f from the common pad 81e. The separation groove 85 extends in the X direction along the upper surface of the +Y side extension portion 60a.

[0069] <Flow channel cover 34> As shown in Figure 3, the flow path cover 34 sandwiches the flow path frame member 31 and the chip module 37 between itself and the nozzle plate 39. The flow path cover 34 includes a cover base 90, an inlet port 91, and an outlet port 92. The cover base 90 is a rectangular plate-shaped structure whose plan view outline is the same as that of the flow path frame member 31. The cover base 90 is superimposed on the upper surfaces of the flow path frame member 31 and the chip module 37. The cover base 90 is joined to the upper surfaces of the flow path frame member 31 and the chip module 37 via adhesive or the like, and is fastened to the flow path frame member 31 with screws or the like. In this way, the cover base 90 closes the upper end openings of the inlet common flow path 31b and the outlet common flow path 31c. Furthermore, by being superimposed on the frame portion 60, the cover base 90 closes the common recess 65 from above.

[0070] A slit 90a is formed in the central part of the cover base 90 in the Y direction. The slit 90a penetrates the cover base 90 in the Z direction and extends in the X direction. The slit 90a is formed in a position that overlaps with the central part (excluding the outer periphery) of the chip module 37 in a plan view. That is, the Y-direction dimension of the slit 90a is smaller than the Y-direction dimension of the chip module 37. The X-direction dimension of the slit 90a is smaller than the X-direction dimension of the chip module 37. The slit 90a exposes at least a portion of the common pad 81e and the individual pad 82f on the upper surface of the support plate 42.

[0071] The inlet port 91 is located at the +Y and +X ends of the cover base 90. The inlet port 91 protrudes upward from the cover base 90. The inlet port 91 communicates with the common inlet channel 31b through the +X end of the common inlet channel 31b (the portion that protrudes relative to the chip housing 31a). In other words, the ink flowing through the ink supply pipe 21 is supplied to the common inlet channel 31b through the inlet port 91. The outlet port 92 is located at the -Y and -X ends of the cover base 90. The outlet port 92 protrudes upward from the cover base 90. The outlet port 92 communicates with the common outlet channel 31c through the -X end of the common outlet channel 31c (the portion that protrudes relative to the chip housing 31a). In other words, the ink flowing through the common outlet channel 31c is discharged to the ink discharge pipe 22 through the outlet port 92.

[0072] The flexible printed circuit board 35 is pressed against the upper surface of the support plate 42 through a slit 90a. The flexible printed circuit board 35 is connected to a common pad 81e and individual pads 82f on the upper surface of the support plate 42. After being pulled out above the head chip 32 through an opening 42a, the flexible printed circuit board 35 is connected to the control unit.

[0073] [How to operate Printer 1] Next, the case of recording characters, figures, etc., onto the recording medium P using the printer 1 described above will be explained below. Initially, the four ink tanks 4 shown in Figure 1 are assumed to be sufficiently filled with ink of a different color. Furthermore, the ink in the ink tanks 4 is filled into the inkjet head 5 via the ink circulation mechanism 6.

[0074] Under these initial conditions, when printer 1 is activated, the recording medium P is carried to the +X side while being gripped by the rollers 11 and 12 of transport mechanisms 2 and 3. At the same time, carriage 29 moves in the Y direction, causing the inkjet head 5 mounted on carriage 29 to move back and forth in the Y direction. As the inkjet head 5 moves back and forth, ink is ejected from each inkjet head 5 onto the recording medium P as needed. This allows for the recording of characters, images, and other data onto the recording medium P.

[0075] The movement of each inkjet head 5 is described in detail below. In a circulating side-chute type inkjet head 5 like the first embodiment, ink is first circulated through the circulation channel 23 by operating the pressure pump 24 and suction pump 25 shown in Figure 2. In this case, the ink circulating in the ink supply pipe 21 is supplied to the common inlet channel 31b through the inlet port 91. As shown in Figure 6, the ink supplied to the common inlet channel 31b flows into the inlet connecting passage 71. The ink that has flowed into the inlet connecting passage 71 flows into the pressure chamber 50 through the +Y side opening in the corresponding pressure chamber 50. The ink flowing to the -Y side within the pressure chamber 50 is discharged to the common outlet channel 31c through the -Y side opening of the pressure chamber 50. The ink discharged to the common outlet channel 31c flows into the ink discharge pipe 22 through the outlet port 92 and is returned to the ink tank 4. This allows ink to be circulated between the inkjet head 5 and the ink tank 4.

[0076] Then, when the reciprocating movement of the inkjet head 5 begins due to the movement of the carriage 29 (see Figure 1), a drive voltage is applied between the common electrode 81a and the individual electrodes 82a to 82c via the flexible printed circuit board 35. At this time, the common electrode 81a is set to the reference potential GND, and the individual electrodes 82a to 82c are set to the drive potential Vdd when the drive voltage is applied. As a result, a potential difference is created between the common electrode 81a and the individual electrodes 82a to 82c facing each other across the opposing part 55, and an electric field is generated in the opposing part 55.

[0077] Specifically, a potential difference is generated in the Z direction between the common electrode 81a and the first individual electrode 82a. Due to the potential difference in the Z direction, an electric field is generated in the opposing portion 55 in a direction parallel to the polarization direction (Z direction). As a result, the actuator plate 41 expands and contracts in the Z direction due to the bend mode. In addition, a potential difference is generated in the X direction between the common electrode 81a and the second individual electrode 82b, and between the common electrode 81a and the third individual electrode 82c. Due to the potential difference in the X direction, an electric field is generated in the drive wall 59, causing the drive wall 59 to undergo thickness sliding deformation in the Z direction due to the shear mode. As a result, the portions of the opposing portion 55 corresponding to each pressure chamber 50 undergo shear deformation upward from both ends in the X direction towards the center. In other words, in the head chip 32 of the first embodiment, the deformation caused by the shear mode and bend mode of the actuator plate 41 extends in the Z direction. Specifically, when a drive voltage is applied, the actuator plate 41 (opposing portion 55) deforms in a direction away from the pressure chamber 50. This increases the volume inside the pressure chamber 50.

[0078] Subsequently, when the drive voltage is reduced to zero, the opposing part 55 returns to its original state, causing the volume inside the pressure chamber 50 to return to its original size. During the process of the actuator plate 41 returning to its original state, the pressure inside the pressure chamber 50 increases, and the ink inside the pressure chamber 50 is ejected to the outside through the nozzle hole 39a. The ink ejected to the outside lands on the recording medium P, and the printed information is recorded on the recording medium P.

[0079] <Manufacturing method for the discharge unit 30> Next, the manufacturing method of the discharge unit 30 will be described. Figure 10 is a flowchart illustrating the manufacturing method of the discharge unit 30. As shown in Figure 10, the manufacturing method for the ejection unit 30 includes a support plate processing step S11, a first actuator processing step S12, a first joining step S13, a first film deposition step S14, a second actuator processing step S15, a second film deposition step S16, an inspection step S17, an assembly step S18, and a second joining step S19. For convenience, the following explanation will use the case where the chip module 37 is manufactured at the chip level as an example.

[0080] Figures 11 and 12 are process diagrams illustrating the support plate processing process S11, and are cross-sectional views corresponding to Figure 6. In the support plate processing step S11, as shown in Figure 11, an opening 42a and a common recess 65 are formed in the support plate 42. Specifically, in the support plate processing step S11, sandblasting or the like is performed on the upper surface of the support plate 42. Subsequently, as shown in Figure 12, grinding is performed on the lower surface of the support plate 42 to open the lower end opening of the opening 42a.

[0081] Figure 13 is a process diagram illustrating the first actuator machining process S12, and is a cross-sectional view corresponding to Figure 7. As shown in Figure 13, in the first actuator processing step S12, a dividing recess 52 is formed in the actuator plate 41 (dividing recess formation step). Specifically, the dividing recess 52 is formed by dicing or the like on the upper surface of the actuator plate 41.

[0082] Figure 14 is a process diagram illustrating the first joining process S13, and is a cross-sectional view corresponding to Figure 7. As shown in Figure 14, in the first joining step S13, the support plate 42 is attached to the upper surface of the actuator plate 41 using an adhesive or the like.

[0083] Figure 15 is a process diagram illustrating the first film deposition process S14, and is a cross-sectional view corresponding to Figure 7. As shown in Figure 15, in the first film deposition step S14, various wirings (through wiring 81d, common pad 81e, and individual wiring 82) are formed on the portion of the drive wiring that is exposed above the chip module 37. In the first film deposition step S14, electrode material is deposited from an oblique upward direction that intersects the Z direction when viewed from the Y direction, for example by oblique deposition. In this case, oblique deposition is performed from both the +X side and the -X side when viewed from the Y direction. As a result, various wirings are deposited on the portion exposed above the chip module 37. After the electrode material is deposited, the various wirings are separated using a laser or a dicer.

[0084] Figures 16 to 18 are process diagrams illustrating the second actuator machining process S15, and are cross-sectional views corresponding to Figure 6. As shown in Figure 16, in the second actuator processing step, individual flow channels 51 (pressure chambers 50) are formed on the lower surface of the actuator plate 41. The individual flow channels 51 are formed, for example, by dicing the lower surface of the actuator plate 41. Next, as shown in Figure 17, in the second actuator processing step, a connection groove 70 is formed in the chip module 37. The connection groove 70 is formed by dicing or the like from below the chip module 37 through the electrode formation groove 51b. Next, as shown in Figure 18, in the second actuator processing step, an inlet passage 71 is formed in the chip module 37. The inlet passage 71 is formed by dicing or the like from below the chip module 37.

[0085] Figure 19 is a process diagram illustrating the second film deposition process S16, and is a cross-sectional view corresponding to Figure 6. As shown in Figure 19, in the second film deposition step S16, various wirings (common electrode 81a and routing wiring 81b) are formed on the portion of the drive wiring that faces downwards on the chip module 37. In the second film deposition step S16, electrode material is deposited from a diagonal downward direction that intersects the Z direction when viewed from the Y direction, for example by oblique deposition. In this case, diagonal deposition is performed from both the +X side and the -X side when viewed from the Y direction. As a result, various wirings are deposited on the inner surfaces of the electrode formation groove 51b and the connection groove 70.

[0086] With the above steps completed, the chip module 37 is finished. When manufacturing the chip module 37 at the wafer level, the same processes as described above are performed on the actuator plate wafer and the support plate wafer to form a wafer stack. Subsequently, multiple chip modules are extracted by separating the wafer stack into individual pieces.

[0087] In inspection step S17, a continuity test is performed on the chip module 37 on which the drive wiring has been formed. If normal continuity is confirmed in inspection step S17, it is determined to be a good product and the process proceeds to the next step. On the other hand, if poor continuity is confirmed in inspection step S17, it is determined to be a defective product. If a chip module 37 is determined to be a defective product, the drive wiring may be reworked. Possible rework methods include, for example, melting the drive wiring and then repeating the film deposition steps S14 and S16.

[0088] Subsequently, in assembly step S18, the chip module 37 is assembled to the flow channel frame member 31. Specifically, the chip module 37 is fitted into the chip housing portion 31a so that the lower surface of the flow channel frame member 31 and the lower surface of the chip module 37 are flush with each other.

[0089] Next, in the second joining step S19, the nozzle plate 39 is attached so as to cover both the lower surface of the flow path frame member 31 and the lower surface of the chip module 37. After that, the flow path cover 34 is attached to the upper surface of the flow path frame member 31. With the above steps completed, the discharge unit 30 is finished.

[0090] Thus, the head chip 32 of the first embodiment includes a nozzle plate (injection hole plate) 39 on which a plurality of nozzle holes (injection holes) 39a penetrating in the Z direction (first direction) are arranged in the X direction (second direction), and a chip module (chip body) 37 provided facing the nozzle plate 39 in the Z direction so as to form a plurality of pressure chambers 50 communicating with each of the nozzle holes 39a between the nozzle plate 39 and the nozzle plate 39. The chip body includes an opposing portion (actuator portion) 55 having an electrode forming groove (first groove) 51b that opens on the lower surface (first surface) of the opposing portion 55 and is provided for each pressure chamber 50, and a dividing recess (second groove) 52 that opens on the upper surface (second surface) of the opposing portion 55 and is aligned in the X direction with respect to the electrode forming groove 51b, and an opening 42a formed on the side of the opposing portion 55 opposite to the nozzle plate 39 that exposes at least a part of the dividing recess 52, and a frame portion 60 that surrounds the electrode forming groove 51b and the dividing recess 52 in a plan view. The actuator plate 41 includes a common electrode (first electrode) 81a formed on the inner surface of the electrode forming groove 51b, and a second electrode (second individual electrode 82b or third individual electrode 82c) formed on the inner surface of the dividing recess 52 that generates an electric field in the actuator plate 41 by creating a potential difference with the common electrode 81a. With this configuration, the electrode forming groove 51b and the dividing recess 52 are opened separately on the upper and lower surfaces of the opposing portion 55, and the frame portion 60 is provided on the side of the opposing portion 55 opposite to the nozzle plate 39, making it easier to ensure the rigidity of the chip module 37. This improves handling during manufacturing and increases manufacturing efficiency. Furthermore, in the first embodiment, electrode material can be introduced into the frame portion 60 through the opening 42a during the manufacturing of the chip module 37. This makes it easier to inspect the individual electrodes 82a to 82c, etc., through the opening 42a after their formation. As a result, yield can be improved, for example, by allowing rework in the event of a film deposition defect.

[0091] In the head chip 32 of the first embodiment, the frame portion 60 surrounds all the electrode forming grooves 51b and dividing recesses 52 when viewed from the Z direction. With this configuration, since no frame portion 60 is placed between adjacent dividing recesses 52 in the X direction, a large opening 42a can be secured. Therefore, when forming individual electrodes 82a to 82c through the opening 42a, the electrode material is prevented from being obstructed by the frame portion 60. As a result, individual electrodes 82b and 82c can be deposited in the dividing recesses 52 with high precision, and the yield can be improved.

[0092] In the head chip 32 of the first embodiment, the chip module 37 includes an actuator plate 41 that constitutes the opposing portion 55, and a support plate 42 that constitutes the frame portion 60 and is laminated on the actuator plate 41. With this configuration, the support plate 42 can be stacked after the dividing recess 52 is formed, thereby improving processability.

[0093] In the head chip 32 of the first embodiment, a portion of the divided recess 52 overlaps with the frame portion 60 when viewed from the Z direction. This configuration makes it easier to secure the dimensions of the dividing recess 52 compared to the case where the dividing recess 52 is housed inside the frame 60. This makes it easier to secure the area of ​​the individual electrodes 82b and 82c and to improve the pressure generated in the pressure chamber 50 during ink ejection.

[0094] In the head chip 32 of the first embodiment, the frame portion 60 has a common pad (first pad) 81e connected to a common electrode 81a and on which a flexible printed circuit board (external wiring) 35 is mounted, and individual pads (second pads) 82f connected to individual electrodes 82a to 82c and on which a flexible printed circuit board 35 is mounted. In this configuration, the portion where the opposing portion 55 and the frame portion 60 overlap is a part of the chip module 37 that has a large dimension in the Z direction and high rigidity. Therefore, by forming the common pad 81e and individual pads 82f on the frame portion 60, it is possible to withstand the load when mounting the flexible printed circuit board 35. Furthermore, in the head chip 32 of the first embodiment, as described above, the dividing recess 52 is open through the opening 42a, so that each pad 81e, 82f and the individual electrodes 82a to 82c can be deposited simultaneously in the film deposition process. This reduces manufacturing man-hours and lowers costs.

[0095] In the head chip 32 of the first embodiment, the common pad 81e and the individual pads 82f are formed on the upper surface (surface) of the frame portion 60. Of the inner circumferential surface of the opening 42a (frame portion 60), the portion located between the individual electrodes 82a to 82c and the individual pads 82f is formed as an inclined surface that slopes upward in a direction in which the dimensions of the opening 42a expand. On the inclined surface (inner circumferential surface of the +Y side extending portion 60a), routing wiring 82e is formed to connect the individual electrodes 82a to 82c and the individual pads 82f. With this configuration, the inner circumferential surface of the +Y side extension portion 60a is formed as an inclined surface, making it easier to form the routing wiring 82e in the first film deposition process S14. This ensures the reliability of conductivity and improves yield.

[0096] In the head chip 32 of the first embodiment, the opposing portion 55 is set with the Z direction as the polarization direction. On the upper surface of the opposing portion 55, a first individual electrode (third electrode) 82a is formed at a position facing the common electrode 81a in the Z direction, which generates an electric field in the opposing portion 55 by creating a potential difference between it and the common electrode 81a. This configuration allows for the generation of an electric field in the Z direction (polarization direction) of the opposing portion 55. This enables the opposing portion 55 to be deformed in the Z direction in bend mode (unimorph type). This allows for further improvement of the generated pressure.

[0097] In the head chip 32 of the first embodiment, the actuator plate 41 protrudes downward from the opposing portion 55 and is provided with a partition portion 54 that separates adjacent pressure chambers 50. With this configuration, the lower surface of the opposing part 55 is positioned away from the nozzle plate 39, allowing the opposing part 55 to deform smoothly when an electric field is generated on it. This ensures sufficient deformation of the opposing part 55 and makes it easier to improve the pressure generated in the pressure chamber 50 during ink ejection.

[0098] Since the inkjet head 5 and printer 1 of the first embodiment are equipped with the head chip 32, yield can be improved and costs can be reduced.

[0099] (Second Embodiment) Figure 20 is a cross-sectional view of the discharge unit 30 according to the second embodiment, and is a cross-sectional view corresponding to Figure 7. As shown in Figure 20, the discharge unit 30 of the second embodiment differs from the first embodiment in that the frame portion 60 is formed integrally with the actuator plate 41. That is, the actuator plate 41 includes a partition portion 54 and an opposing portion 55, as well as a frame portion 60 that protrudes upward from the outer circumference of the opposing portion 55. In this case, the dividing recess 52 can be formed by, for example, dicing the bottom surface of the opening 42a after the opening 42a has been formed.

[0100] In the head chip 32 of the second embodiment, the opposing portion 55 and the frame portion 60 of the chip module 37 are integrally formed. This configuration allows for a reduction in the number of parts and eliminates the joining process between the actuator plate 41 and the support plate 42 (first joining process S13). This improves manufacturing efficiency and reduces costs. Furthermore, since no adhesive is interposed between the opposing part 55 and the frame part 60, it is possible to prevent, for example, the adhesive from hindering the conductivity of the drive wiring.

[0101] (Third embodiment) Figure 21 is a plan view of the discharge unit 30 according to the third embodiment, corresponding to Figure 8. Figure 22 is a cross-sectional view of the discharge unit 30 according to the third embodiment, corresponding to Figure 6. Figure 23 is a cross-sectional view of the discharge unit 30 according to the third embodiment, corresponding to Figure 7. As shown in Figures 21 to 23, the discharge unit 30 of the third embodiment differs from the first embodiment in that the first connection groove 100, the second connection groove 101, and the third connection groove 102 are formed in the frame portion 60.

[0102] As shown in Figures 21 and 22, the first connecting groove 100 is formed on the inner circumferential surface of the +Y-side extending portion 60a at the same position as the first individual electrode 82a in the X direction. The first connecting groove 100 penetrates the support plate 42 in the Z direction and opens on the inner circumferential surface of the +Y-side extending portion 60a. The bottom surface of the first connecting groove 100 is formed as an inclined surface that curves upward as it approaches the +Y side. The first connecting groove 100 is formed, for example, after the first joining process S13 by performing dicing or the like on the support plate 42 from above.

[0103] A first routing wire 110a is formed on the inner surface of the first connection groove 100. The first routing wire 110a is formed on the inner surface and bottom surface of the first connection groove 100 that face each other in the X direction. The first routing wire 110a connects the first individual electrode 82a and the individual pad 82f.

[0104] As shown in Figures 21 and 23, the second connecting groove 101 is formed in the same position as the +X-side dividing recess 52a in the X direction. The second connecting groove 101 penetrates the support plate 42 in the Z direction and opens on the inner circumferential surface of the +Y-side extending portion 60a. The bottom surface of the second connecting groove 101 is formed in an arc shape, similar to the bottom surface of the first connecting groove 100. A second routing wire 110b is formed on the inner surface of the second connection groove 101. The second routing wire 110b is formed on the inner surface and bottom surface of the second connection groove 101 that face each other in the X direction. The second routing wire 110b connects the second individual electrode 82b and the individual pad 82f corresponding to one pressure chamber 50.

[0105] The third connecting groove 102 is formed in the same position as the -X-side dividing recess 52b in the X direction. The third connecting groove 102 penetrates the support plate 42 in the Z direction and opens on the inner circumferential surface of the +Y-side extending portion 60a. The bottom surface of the third connecting groove 102 is formed in an arc shape, similar to the bottom surface of the first connecting groove 100. A third routing wire 110c is formed on the inner surface of the third connection groove 102. The third routing wire 110c is formed on the inner surface and bottom surface of the third connection groove 102 that face each other in the X direction. The third routing wire 110c connects the third individual electrode 82c and the individual pad 82f corresponding to one pressure chamber 50.

[0106] Furthermore, the second routing 110b corresponding to one pressure chamber 50 and the third routing 110c corresponding to the other pressure chamber 50 adjacent to the first pressure chamber 50 on the +X side are separated at the bottom of the second connection groove 101. Also, the third routing 110c corresponding to one pressure chamber 50 and the second routing 110b corresponding to the other pressure chamber 50 adjacent to the first pressure chamber 50 on the -X side are separated at the bottom of the third connection groove 102.

[0107] In the head chip 32 of the third embodiment, when the electrode material is deposited from an oblique upward direction that intersects the Z direction when viewed from the Y direction, the inner surface of each connection groove 100 to 102 intersects with the deposition direction of the electrode material. This makes it easier to secure the area of ​​the routing wiring 110a to 110c, which improves the yield by suppressing wire breakage and reduces power consumption by reducing resistance.

[0108] In the head chip 32 of the third embodiment, the chip module 37 includes an actuator plate 41 having an upper surface (first forming surface) on which individual electrodes 82a to 82c are formed, and a support plate (cover portion) 42 having an upper surface (second forming surface) on which individual pads 82f are formed, and provided on the side of the actuator plate 41 opposite to the pressure chamber 50. With this configuration, individual electrodes 82a to 82c can be routed in the Z direction through each connection groove 100 to 102. Furthermore, since each connection groove 100 to 102 penetrates the support plate 42 in the Z direction, the wiring 110a to 110c can be routed between the upper and lower surfaces of the support plate 42.

[0109] (Fourth Embodiment) Figure 24 is a cross-sectional view of the discharge unit 30 according to the fourth embodiment, corresponding to Figure 6. Figure 25 is a cross-sectional view of the discharge unit 30 according to the fourth embodiment, corresponding to Figure 7. Figure 26 is a cross-sectional view corresponding to the line XXVI-XXVI in Figure 24. As shown in Figures 24 to 26, the discharge unit 30 of the fourth embodiment differs from the first embodiment in that an inlet connecting passage 71 is not formed. Specifically, the chip module 37 has an inlet connection groove 200 and an outlet connection groove 201 formed therein.

[0110] The inlet connection groove 200 opens at the top surface of the main flow channel 51a and extends linearly from the electrode formation groove 51b toward the +Y side. The +Y side end of the inlet connection groove 200 is open at the +Y side end surface of the chip module 37. The individual flow channels 51 and the inlet connection groove 200 are directly connected to the common inlet flow channel 31b.

[0111] The outlet connection groove 201 opens at the top surface of the main flow channel 51a and extends linearly from the electrode formation groove 51b toward the -Y side. The -Y side end of the outlet connection groove 201 is open at the -Y side end surface of the chip module 37. The individual flow channels 51 and the outlet connection groove 201 are directly connected to the common outlet flow channel 31c.

[0112] In the discharge unit 30 of the fourth embodiment, the individual flow paths 51 and the common flow paths 31b and 31c are connected via corresponding connecting grooves 200 and 201. Therefore, the flow path length between the individual flow paths 51 and the common flow paths 31b and 31c can be secured, thereby suppressing crosstalk between adjacent pressure chambers 50.

[0113] (Other variations) The scope of this disclosure is not limited to the embodiments described above, and various modifications can be made without departing from the spirit of this disclosure. For example, in the above embodiment, an inkjet printer 1 was used as an example of a liquid jet recording device, but it is not limited to a printer. For example, a fax machine or an on-demand printing machine may also be used. In the above embodiment, a configuration in which the inkjet head moves relative to the recording medium during printing (a so-called shuttle machine) was described as an example, but the invention is not limited to this configuration. The configuration according to this disclosure may also be adopted in a configuration in which the recording medium is moved relative to the inkjet head while the inkjet head is fixed (a so-called fixed-head machine). In the above embodiment, the case where the recording medium P is paper was described, but the configuration is not limited to this. The recording medium P is not limited to paper; it may be a metal material, a resin material, or even food. In the above embodiment, a configuration in which the liquid spray head is mounted on a liquid spray recording device has been described, but the configuration is not limited to this. That is, the liquid sprayed from the liquid spray head is not limited to what is to be sprayed onto the recording medium, but may also be, for example, a drug solution to be mixed in a compounding agent, a food additive such as a seasoning or flavoring to be added to food, or a fragrance to be sprayed into the air.

[0114] In the above embodiment, a configuration in which the Z direction coincides with the direction of gravity was described, but the configuration is not limited to this, and the Z direction may be aligned with the horizontal direction. In the embodiments described above, the pressure chamber 50 was formed in a groove shape that linearly penetrates the chip module 37 in the Y direction, but the configuration is not limited to this. The pressure chamber 50 may extend inclined with respect to the Y direction, as long as it has a component in the Y direction.

[0115] In the above embodiment, a configuration was described in which the actuator plate 41 is deformed by both the bend mode and the shear mode, but the configuration is not limited to this. The actuator plate 41 only needs to be deformed by at least one of the bend mode and the shear mode. In the above embodiment, a circulating side chute was used as an example, but the configuration is not limited to this. For example, the configuration may involve introducing ink into the individual channel 51 from both sides in the Y direction, or introducing ink into the individual channel 51 from the first side in the Y direction while blocking the second side in the Y direction of the individual channel 51.

[0116] In the above embodiment, a configuration was described in which the opening 42a is formed to expose all the dividing recesses 52 corresponding to the pressure chambers 50 together, but the configuration is not limited to this. The opening 42a may be formed to expose one or more of the dividing recesses 52. In the above embodiment, a configuration was described in which a common electrode 81a is formed on the lower surface of the opposing portion 55 as the first electrode, and individual electrodes 82b and 82c are formed on the upper surface of the opposing portion 55 as the second electrode. However, the configuration is not limited to this. Individual electrodes may be formed on the lower surface of the opposing portion 55, and a common electrode may be formed on the upper surface of the opposing portion 55. In the above embodiment, a configuration in which pads 81e and 82f are formed on the upper surface of the frame portion 60 has been described, but the configuration is not limited to this. Pads 81e and 82f may be formed, for example, on the inner circumferential surface of the frame portion 60.

[0117] In the above embodiment, a configuration was described in which a common electrode 81a and a common pad 81e are connected via routing wiring 81b formed in a connection groove 70, but the connection groove 70 is not an essential component. In the above embodiment, a configuration in which common channels 31b and 31c are formed in the channel frame member 31 has been described, but the configuration is not limited to this. The common channels may also be formed in the actuator plate 41. With this configuration, the common channels can be formed when the head tip 32 is processed, so the effects of warping due to thermal expansion can be reduced. In addition, since the common channels can be formed by the material that forms the pressure chamber, the common channels can be formed by a material with excellent ink resistance.

[0118] Furthermore, it is possible to replace the components in the above embodiments with well-known components as appropriate, without departing from the spirit of this disclosure, and the above modifications may be combined as appropriate. [Explanation of Symbols]

[0119] 1: Printer (liquid jet recording device) 5: Inkjet head (liquid jet head) 32: Head Tip 35: Flexible printed circuit board (external wiring) 37: Chip module (chip itself) 39a: Nozzle hole (injection hole) 41: Actuator plate (actuator part) 42: Support plate 42a: Opening 50: Pressure chamber 51b: Electrode formation groove (first groove) 52: Dividing recess (second groove) 54: Partition section 55: Opposing part (actuator part) 60: Frame 81a: Common electrode (first electrode) 81e: Common pad (first pad) 82a: 1st individual electrode (3rd electrode) 82b: Second individual electrode (second electrode) 82c: Third individual electrode (second electrode) 82e: Wiring 82f: Individual pad (2nd pad) 110a: First routing wiring (routing wiring) 110b: Second routing (routing) 110c: Third routing wiring (routing wiring)

Claims

1. Multiple injection holes penetrating in a first direction are arranged in a second direction intersecting the first direction on an injection hole plate, The chip body is provided facing the injection hole plate in a first direction, such that it forms a plurality of pressure chambers communicating with each of the plurality of injection holes between itself and the injection hole plate, The chip body is An actuator section having a first groove that opens on a first surface facing the injection hole plate in the first direction and is provided for each pressure chamber, and a second groove that opens on a second surface facing the opposite side of the injection hole plate in the first direction and is aligned with the first groove in the second direction, On the side of the actuator portion opposite to the injection hole plate, an opening is formed that exposes at least a portion of the second groove, and a frame portion surrounds the first groove and the second groove when viewed from the first direction, The actuator section includes: A first electrode formed on the inner surface of the first groove, A head tip comprising a second electrode formed on the inner surface of the second groove, which generates an electric field in the actuator by creating a potential difference between itself and the first electrode.

2. The head tip according to claim 1, wherein the frame portion surrounds all of the first grooves and second grooves when viewed from the first direction.

3. The chip body is The actuator plate constituting the actuator section, The head chip according to claim 1 or claim 2, comprising a support plate which constitutes the frame portion and is laminated on the actuator plate.

4. The head tip according to claim 3, wherein a portion of the second groove overlaps with the frame portion when viewed from the first direction.

5. The head chip according to claim 1 or claim 2, wherein the chip body is configured such that the actuator portion and the frame portion are integrally formed.

6. The aforementioned frame portion includes: A first pad connected to the first electrode and on which external wiring is mounted, A head tip according to claim 1 or claim 2, wherein a second pad is formed which is connected to the second electrode and on which the external wiring is mounted.

7. The first pad and the second pad are formed on the surface of the frame portion that faces away from the actuator portion in the first direction, Of the inner circumferential surface of the opening, the portion located between the second electrode and the second pad is formed as an inclined surface that inclins in a direction such that the dimensions of the opening expand as it approaches the surface in the first direction. The head tip according to claim 6, wherein the inclined surface has routing wiring formed thereon for connecting the second electrode and the second pad.

8. The actuator unit is set with the first direction as the polarization direction, The head tip according to claim 1 or claim 2, wherein a third electrode is formed on the second surface of the actuator portion at a position facing the first electrode in the first direction, and generates an electric field in the actuator portion by creating a potential difference between itself and the first electrode.

9. The head tip according to claim 1 or 2, wherein the actuator portion protrudes in the first direction from a portion of the first surface located between adjacent first grooves in the second direction, and includes a partition portion that separates adjacent pressure chambers.

10. A liquid spray head comprising the head tip described in claim 1 or claim 2.

11. A liquid injection recording device comprising the liquid injection head described in claim 10.

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