Head chip, liquid ejection head, and liquid ejection recording apparatus

Abstract

Provided are a head chip, a liquid ejection head, and a liquid ejection recording apparatus capable of ensuring electrical reliability and improving durability. A head chip (50) according to one aspect of the present disclosure includes a discharge passage (61) and a non-discharge passage (62) extending in a Z direction, an actuator plate (53) in which the discharge passage (61) and the non-discharge passage (62) are alternately arranged in an X direction, and a nozzle plate having a nozzle hole communicating with the discharge passage (61) and facing the actuator plate (53). The non-discharge passage (62) ends at a position separated from a lower end surface of the actuator plate (53). The discharge passage (61) is open on the lower end surface of the actuator plate (53).

Description

TECHNICAL FIELD

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

[0002] An inkjet head mounted on an inkjet printer discharges ink to a recording medium by a head chip mounted on the inkjet head. The head chip has an actuator plate in which discharge passages and non-discharge passages are alternately arranged across a driving wall, and a nozzle plate having nozzle holes communicating with the discharge passages. The discharge passages and the non-discharge passages are alternately arranged across the driving wall (for example, refer to Patent Literature 1 described below).

[0003] In the head chip, in order to discharge ink, a voltage is applied between electrodes formed in the driving wall to cause the driving wall to undergo thickness-sliding deformation. Thereby, the volume in the discharge passage changes, and the ink in the discharge passage is discharged through the nozzle hole.

[0004] PRIOR ART DOCUMENTS

[0005] PATENT LITERATURE

[0006] Patent Literature 1: Japanese Patent Application Publication No. 2018-122553 SUMMARY

[0007] PROBLEMS TO BE SOLVED BY THE INVENTION

[0008] However, regarding the head chip, there is a possibility that a minute gap is unintentionally formed between the actuator plate and the nozzle plate due to surface property deviation or poor adhesion of the actuator plate and the nozzle plate, or the like. Assuming that if the ink in the discharge passage flows into the non-discharge passage through the minute gap, there is a possibility that the electrodes formed on the inner surface of the non-discharge passage are corroded or short-circuited by the ink.

[0009] The present disclosure provides a head chip, a liquid ejection head, and a liquid ejection recording apparatus capable of ensuring electrical reliability and improving durability.

[0010] SOLUTION TO THE PROBLEM

[0011] To solve the above problem, the present application adopts the following configuration.

[0012] (1) A head chip according to one aspect of the present application includes an actuator plate in which discharge passages and non-discharge passages are alternately arranged in a second direction intersecting a first direction in which the discharge passages extend, and a nozzle plate having nozzle holes communicating with the discharge passages and facing the actuator plate, the non-discharge passages terminating at positions separated from an opposing surface of the actuator plate to the nozzle plate, and the discharge passages opening on the opposing surface.

[0013] According to the present aspect, the non-ejection passage is not open on the facing surface, and thus it is possible to suppress entry of liquid in the non-ejection passage through a minute gap unintentionally formed between the facing surface of the actuator plate and the ejection hole plate.

[0014] Therefore, it is possible to provide a head chip in which electrode corrosion or short circuit formed on the inner surface of the non-ejection passage is suppressed, electrical reliability is excellent, and improvement of durability is sought. In addition, the surface properties required for the facing surface of the actuator plate can be relaxed, and thus improvement of manufacturing efficiency or improvement of yield can be sought.

[0015] (2) In the head chip according to the aspect (1), it is preferable that an intermediate plate in which communication passages that respectively communicate the ejection passages and the ejection holes are formed be disposed between the actuator plate and the ejection hole plate.

[0016] According to the present aspect, the non-ejection passage is not open on the facing surface, and thus it is possible to ensure the size of the communication passage in the second direction to a greater extent. Therefore, it is easy to allow positional displacement in the second direction, for example, between the ejection hole and the communication passage or between the ejection passage and the communication passage. Thus, it is possible to ensure the flow cross-sectional area of the communication portion between the ejection hole and the communication passage or between the ejection passage and the communication passage.

[0017] (3) In the head chip according to the aspect (2), it is preferable that a flow path member facing a surface other than the facing surface in the actuator plate be provided, and the flow path member have an inlet flow path communicating with the plurality of ejection passages and an outlet flow path communicating with the plurality of communication passages in unison.

[0018] According to the present aspect, it is possible to ensure the size of the communication passage in the second direction to a greater extent, and thus it is easy to ensure the flow cross-sectional area of the communication passage. In this case, it is possible to increase the flow rate of liquid flowing in the communication passage, and thus it is possible to seek to suppress bubble blockage at the ejection hole or to increase the ejection amount of liquid through the ejection hole. In addition, it is easy to dissipate, for example, pressure variation generated in one ejection passage at the time of liquid ejection in the communication passage. Therefore, even in the case where a plurality of ejection passages are communicated through the outlet flow path, it is possible to suppress so-called crosstalk in which pressure variation generated in one ejection passage propagates to other ejection passages through the communication passage and the outlet flow path.

[0019] On the other hand, it is possible to ensure the size of the communication passage in the second direction to a greater extent, and thus it is possible to ensure the flow cross-sectional area of the communication passage while suppressing the thickness (size in the first direction) of the intermediate plate. It is thus possible to effectively propagate pressure variation generated in the ejection passage at the time of liquid ejection up to the ejection hole.

[0020] As a result, it is possible to improve the ejection performance.

[0021] (4) In the head chip according to the aspect (1), it is preferable that the facing surface be a surface of the actuator plate facing the first direction, that a flow path member be provided along a thickness direction of the actuator plate that intersects the second direction as viewed in the first direction, and that the flow path member include: circulation paths formed in portions of the actuator plate located between the non-ejection passage and the facing surface in the first direction and communicating with the ejection passage; an inlet flow path formed in a portion of the actuator plate located on a side opposite the facing surface in the first direction and communicating with the ejection passage; and an outlet flow path communicating with the circulation paths.

[0022] According to this aspect, the non-ejection passage is not open at the facing surface, so the size of the circulation path in the second direction can be ensured to be large, and the flow path cross-sectional area of the circulation path can be easily ensured to be large. In this case, the flow rate of liquid flowing in the circulation path can be increased, so it is possible to suppress bubble blockage at the ejection hole or increase the amount of liquid ejected through the ejection hole. In addition, pressure fluctuations generated in one ejection passage, for example, at the time of liquid ejection, can be easily dissipated in the circulation path. Thus, even in the case where a plurality of ejection passages are connected by the outlet flow path, it is possible to suppress so-called crosstalk in which pressure fluctuations generated in one ejection passage propagate to other ejection passages through the circulation path and the outlet flow path.

[0023] On the other hand, the size of the circulation path in the second direction can be ensured to be large, so it is possible to ensure the flow path cross-sectional area of the circulation path while suppressing the thickness (size in the first direction) of the intermediate plate. Thus, pressure fluctuations generated in the ejection passage at the time of liquid ejection can be effectively propagated to the ejection hole.

[0024] As a result, it is possible to improve the ejection performance.

[0025] (5) In the head chip according to the aspect (4), it is preferable that the flow path cross-sectional area of the circulation path increase as it moves away from the ejection passage.

[0026] According to this aspect, the flow path cross-sectional area of the circulation path can be increased gradually, so it is possible to suppress bubble blockage at the ejection hole or increase the amount of liquid ejected through the ejection hole.

[0027] In addition, pressure fluctuations generated in one ejection passage, for example, at the time of liquid ejection, can be easily dissipated in the circulation path, so it is possible to suppress crosstalk.

[0028] (6) In the head chip according to the aspect (4) or (5), it is preferable that the end surface of the facing surface side in the non-ejection passage be formed as an inclined surface extending in a direction in which the flow path member moves away from the thickness direction as it moves toward the facing surface in the first direction.

[0029] According to the present aspect, it is easy to secure the area of the portion in the flow path member that is located between the end surface of the non-ejection passage and the opposing surface on the surface that is superimposed on the actuator plate. Therefore, it is possible to secure a larger flow path cross-sectional area of the circulation path. As a result, it is possible to increase the circulation flow rate of the liquid in the head chip, and thus it is possible to seek to suppress bubble blockage at the ejection orifice or to increase the ejection amount of the liquid through the ejection orifice.

[0030] In addition, it is easy to dissipate, for example, pressure fluctuations generated in one ejection passage at the time of liquid ejection in the circulation path, and thus it is possible to suppress crosstalk.

[0031] (7) In the head chip according to any one of the aspects (4) to (6), it is preferable that the circulation path be provided at a position that is away from the opposing surface in the portion of the non-ejection passage in the first direction in the flow path member.

[0032] According to the present aspect, in the end surface of the flow path member that faces the first direction, the circulation path is not open, and thus the entire end surface of the flow path member becomes a flat continuous surface. Therefore, it becomes easy to secure the area of the end surface of the flow path member that is engaged with the ejection orifice plate, and it is possible to secure the engagement strength. As a result, it is easy to secure the durability of the head chip.

[0033] (8) In the head chip according to any one of the aspects (1) to (7), it is preferable that the end surface of the non-ejection passage on the opposing surface side have: a first inclined surface that extends in the first direction away from the opposing surface along a direction that is away from a first surface in the actuator plate that faces a thickness direction that intersects the second direction as viewed from the first direction; and a second inclined surface that is away from the opposing surface in the first direction as away from a second surface in the actuator plate that is located at a position opposite the first surface in the thickness direction, and is connected to the first inclined surface.

[0034] According to the present aspect, compared to a case in which, for example, a dicer is made to enter with respect to the actuator plate from only one surface to form the non-ejection passage, it is possible to suppress the maximum dimension between the end surface of the non-ejection passage and the opposing surface. As a result, it is possible to secure the opposing region of the ejection passage and the non-ejection passage in the second direction. Therefore, it is possible to secure the opposing area of the electrodes formed on the inner surfaces of the ejection passage and the non-ejection passage, respectively, and thus it is possible to secure the pump stroke, and increase the deformation volume of the drive wall at the time of liquid ejection. By increasing the deformation volume of the drive wall, it is possible to reduce the applied voltage for performing the same ejection. In addition, it is possible to expect an increase in the ejection performance such as an increase in the ejection speed at the same applied voltage.

[0035] (9) The liquid ejection head according to one aspect of the present disclosure includes the head chip according to any one of the aspects (1) to (8).

[0036] According to the aspect, the head chip according to the aspect is provided, and thus a liquid ejection head with excellent reliability can be provided.

[0037] (10) The liquid ejection recording apparatus according to one aspect of the present disclosure includes the liquid ejection head according to the aspect (9).

[0038] According to the aspect, the head chip according to the aspect is provided, and thus a liquid ejection recording apparatus with excellent reliability can be provided.

[0039] Effects of the Invention

[0040] According to one aspect of the present disclosure, a head chip, a liquid ejection head, and a liquid ejection recording apparatus that can ensure electrical reliability and improve durability can be provided. BRIEF DESCRIPTION OF DRAWINGS

[0041] Figure 1 is a schematic configuration view of an inkjet printer according to the first embodiment.

[0042] Figure 2 is an exploded perspective view of a head chip according to the first embodiment.

[0043] Figure 3 is a cross-sectional view corresponding to the III-III line of Figure 2

[0044] Figure 4 is a cross-sectional view along the IV-IV line of Figure 2

[0045] Figure 5 is a front view corresponding to the V direction of Figure 2

[0046] Figure 6 is a cross-sectional view corresponding to the VI-VI line of Figure 3

[0047] Figure 7 is a flowchart for explaining a manufacturing method of the head chip according to the first embodiment.

[0048] Figure 8 is a process diagram for explaining the manufacturing method of the head chip according to the first embodiment.

[0049] Figure 9 is a process diagram for explaining the manufacturing method of the head chip according to the first embodiment.

[0050] Figure 10 ​​​​is a process diagram for explaining a manufacturing method of a head chip according to the first embodiment.

[0051] Figure 11 is a process diagram for explaining a manufacturing method of a head chip according to the first embodiment.

[0052] Figure 12 is a sectional view showing a section along a non-discharge passage in a head chip according to the modification.

[0053] Figure 13 is a sectional view showing a section along a non-discharge passage in a head chip according to the modification.

[0054] Figure 14 is a sectional view showing a section along a discharge passage in a head chip according to the second embodiment.

[0055] Figure 15 is a sectional view corresponding to XV-XV line of Figure 14 in a state of passing through a return plate in a head chip according to the second embodiment.

[0056] Figure 16 is a front view corresponding to Figure 5 in a head chip according to the second embodiment.

[0057] Figure 17 is a sectional view showing a section along a discharge passage in a head chip according to the third embodiment.

[0058] Figure 18 is a sectional view showing a section along a discharge passage in a head chip according to the modification.

[0059] Figure 19 is a sectional view showing a section along a non-discharge passage in a head chip according to the modification.

[0060] Figure 20 is a sectional view showing a section along a discharge passage in a head chip according to the fourth embodiment.

[0061] Figure 21 is a sectional view showing a section along a non-discharge passage in a head chip according to the fourth embodiment.

[0062] Figure 22 is a sectional view showing a section along a discharge passage in a head chip according to the modification. DETAILED DESCRIPTION

[0063] Hereinafter, an embodiment related to the present disclosure will be described with reference to the drawings. In the embodiment or modification described below, sometimes the same symbol is attached to the corresponding configuration and the description is omitted. Further, in the following description, expressions such as "parallel" or "orthogonal", "center", "coaxial", and the like indicating relative or absolute configurations indicate not only a configuration that is strictly so, but also a state in which there is a relative displacement in angle or distance to the extent that the same function is obtained with a tolerance. In the following embodiment, an inkjet printer (hereinafter, simply referred to as a printer) that records on a recording medium using ink (liquid) is exemplified. Further, in the drawings used in the following description, the scale of each component is appropriately changed so as to be able to identify the size of each component.

[0064] (First Embodiment)

[0065] [Printer 1]

[0066] Figure 1 is a schematic configuration diagram of the printer 1.

[0067] As Figure 1 shown, the printer (liquid ejecting recording device) 1 of the first embodiment is provided with a pair of conveyance mechanisms 2, 3, an ink supply mechanism 4, an inkjet head (liquid ejecting head) 5, and a scanning mechanism 6.

[0068] In the following description, an X, Y, Z orthogonal coordinate system is used as necessary for explanation. In this case, the X direction coincides with the conveyance direction (sub-scanning direction) of the recording medium P (for example, paper or the like). The Y direction coincides with the scanning direction (main scanning direction) of the scanning mechanism 6. The Z direction shows the height direction (gravity direction) orthogonal to the X direction and the Y direction. In the following description, the side of the arrow in the drawing is the positive (+) side in the X direction, the Y direction, and the Z direction, and the side opposite to the arrow is the negative (-) side. In this specification, the +Z side corresponds to the upper side in the gravity direction, and the -Z side corresponds to the lower side in the gravity direction.

[0069] The conveyance mechanisms 2, 3 convey the recording medium P to the +X side. The conveyance mechanisms 2, 3 each include, for example, a pair of rollers 11, 12 extending in the Y direction.

[0070] The ink supply mechanism 4 is provided with an ink tank 15 that accommodates ink, and an ink pipe 16 that connects the ink tank 15 and the inkjet head 5. The ink tank 15 accommodates, for example, four colors of ink, yellow, magenta, cyan, and black, respectively. Each inkjet head 5 is configured so as to be able to eject four colors of ink, yellow, magenta, cyan, and black, respectively, according to the ink tank 15 connected. Further, as the ink, water-based ink that uses water as a solvent can also be used.

[0071] The scanning mechanism 6 causes the inkjet head 5 to reciprocate scanning along the Y direction. The scanning mechanism 6 includes a guide rail 22 and a carriage 23 supported by the guide rail 22 in a manner that allows it to move along the Y direction. When printing on the recording medium P, the inkjet head 5 reciprocates along the Y direction while mounted on the carriage 23.

[0072] <Inkjet Head 5>

[0073] like Figure 1 As shown, the inkjet heads 5 are mounted side-by-side on a carriage 23 along the Y direction. The inkjet head 5 includes: a head chip 50 (see reference). Figure 2 The ink supply unit (not shown) is connected between the ink tank 15 and the head chip 50; and the control unit (not shown) applies a driving voltage to the head chip 50.

[0074] <Head Chip 50>

[0075] Figure 2 This is an exploded 3D view of chip 50.

[0076] Figure 2 The head chip 50 shown is a so-called edge-shoot type head chip 50 that ejects ink from the end of the ejection channel 61 in the extension direction (Z direction) described later. The head chip 50 includes a nozzle plate 51 (see reference). Figure 4 etc.), actuator plate 53 and cover plate (flow path component) 54.

[0077] The actuator plate 53 is a configuration in which a drive plate 55 and a back plate 56 are stacked along the Y direction. The drive plate 55 and the back plate 56 are formed of a piezoelectric material such as PZT (lead zirconate titanate). The drive plate 55 is, for example, a configuration in which two piezoelectric plates with different polarization directions in the Y direction are stacked (a so-called V-shaped configuration). Furthermore, regarding the actuator plate 53, if at least the drive plate 55 is formed of a piezoelectric material, the back plate 56 can also be formed of a material other than a piezoelectric material. Alternatively, the actuator plate 53 can also be formed of a single piezoelectric plate with a single polarization direction over the entire region in the Y direction (thickness direction) (a so-called monopolar configuration).

[0078] An ink-filled ejection channel (jet channel) 61 and an ink-free non-ejection channel (non-jet channel) 62 are formed in the actuator plate 53. Each channel 61, 62 is formed such that, for example, a circular plate cutter enters the actuator plate 53 along the Y direction. Each channel 61, 62 is arranged alternately in the actuator plate 53 at intervals along the X direction (second direction). Furthermore, in this embodiment, a configuration where the channel extension direction coincides with the Z direction (first direction) is described, but the channel extension direction may also intersect the Z direction.

[0079] Figure 3 Is with Figure 2is a cross-sectional view corresponding to the III-III line of FIG. 6. In the following description, the +Y side is referred to as the surface side, the -Y side is referred to as the back side, the +Z side is referred to as the upper side, and the -Z side is referred to as the lower side.

[0080] As shown in FIG. 6, the discharge passage 61 is opened on the surface of the actuator plate 53 and extends in the Z direction. The discharge passage 61 has an extension portion 61a and an upper cut portion 61b. Figure 3

[0081] The extension portion 61a is a portion having the same depth in the Y direction. The lower end of the extension portion 61a is open at the lower end surface of the actuator plate 53. In this embodiment, the extension portion 61a penetrates the drive plate 55 in the Y direction. Therefore, the bottom surface of the extension portion 61a is formed by the surface of the back plate 56.

[0082] The upper cut portion 61b is connected to the upper end of the extension portion 61a. With regard to the upper cut portion 61b, the depth in the Y direction gradually becomes shallower as it goes upward. Specifically, the bottom surface of the upper cut portion 61b is formed as an inclined surface that curves toward the surface side while extending as it goes upward.

[0083] Figure 4 is a cross-sectional view along the IV-IV line of FIG. 6. Figure 2

[0084] As shown in FIG. 6, the non-discharge passage 62 is opened on the surface of the actuator plate 53 and extends in the Z direction. The non-discharge passage 62 has an extension portion 62a and an upper cut portion 62b. Figure 4

[0085] The extension portion 62a is a portion having the same depth in the Y direction. The upper end of the extension portion 62a is open at the upper end surface of the actuator plate 53. In this embodiment, the extension portion 62a penetrates the drive plate 55 in the Y direction. Therefore, the bottom surface of the extension portion 62a is formed by the surface of the back plate 56.

[0086] The upper cut portion 62b is connected to the lower end of the extension portion 62a. With regard to the upper cut portion 62b, the depth in the Y direction gradually becomes shallower as it goes downward. The bottom surface of the upper cut portion 62b (the end surface on the opposite surface side in the non-discharge passage) is formed as an inclined surface that curves toward the surface side while extending as it goes downward.

[0087] Figure 5 is a front view corresponding to the V view of FIG. 6. Figure 2

[0088] As shown in FIG. 6, the portion of the actuator plate 53 between the discharge passage 61 and the non-discharge passage 62 respectively constitutes a drive wall 65. Therefore, with regard to the discharge passage 61, both sides in the X direction are surrounded by the pair of drive walls 65. Figure 2 Figure 5 ​​​​​​

[0089] As Figure 4 shown, a portion of the actuator plate 53 between the lower end surface (a surface opposite the nozzle plate 51) of the actuator plate 53 and the non-discharge passage 62 (a bottom surface) constitutes an occlusion portion 67. The occlusion portion 67 cuts off the communication between the inside and outside of the non-discharge passage 62 in the Z direction. Thus, the non-discharge passage 62 terminates at a position that is away upward from the lower end surface of the actuator plate 53, and is not open at the lower end surface of the actuator plate 53.

[0090] The surface of the occlusion portion 67 that is exposed to the inside of the non-discharge passage 62 (hereinafter, referred to as an occlusion inner surface portion 67a) constitutes a bottom surface of the upper cut portion 62b. On the other hand, the surface of the occlusion portion 67 that faces the side opposite the non-discharge passage 62 (hereinafter, an occlusion outer surface portion 67b) constitutes the lower end surface of the actuator plate 53. Thus, in the present embodiment, the dimension of the occlusion portion 67 in the Z direction gradually increases from the surface side to the back side. Further, the occlusion outer surface portion 67b is not limited to the case where it is flush with the lower end surface of the actuator plate 53. The occlusion outer surface portion 67b can be, for example, recessed upward with respect to the lower end surface of the actuator plate 53.

[0091] Figure 6 is a plan view of the actuator plate 53.

[0092] As Figure 6 shown, a common wiring 71 and an individual wiring 72 are formed in the actuator plate 53. The common wiring 71 has a common electrode 75 and a common terminal 76.

[0093] The common electrode 75 is formed on the inner surface of the discharge passage 61, respectively. The common electrode 75 is formed on the entire region of the inner side surface and the bottom surface of the upper cut portion 61b of the inner surface of the discharge passage 61 facing each other in the X direction.

[0094] The common terminal 76 is formed on the surface of a portion of the actuator plate 53 that is located upward with respect to the discharge passage 61 (hereinafter, referred to as a tail portion 78). The common terminal 76 is formed in a band shape extending in the Z direction on the surface of the tail portion 78. The common terminal 76 is connected to the common electrode 75 at the surface side opening edge of the discharge passage 61.

[0095] The individual wiring 72 has an individual electrode 81 and an individual terminal 82.

[0096] The individual electrode 81 is formed on the inner side surface of the drive wall 65 facing the non-discharge passage 62. The individual electrode 81 is formed on the entire region in the Y direction of the inner side surface of each non-discharge passage 62. Further, the individual electrodes 81 formed on the inner surfaces of the facing inner side surfaces of the non-discharge passage 62 are separated from each other by the bottom surface of the non-discharge passage 62.

[0097] Individual terminals 82 are formed on the surface of the tail 78, located above the common terminal 76. Individual terminals 82 are strip-shaped and extend in the X direction. Individual terminals 82 connect to the individual electrodes 81, which are sandwiched between and opposed in the X direction, at the surface-side opening edge of the non-discharge channels 62 that are opposite each other in the X direction. Furthermore, when using a unipolar type as the actuator plate 53, the common electrode 75 or the individual electrode 81 needs to be formed at a depth of more than half in the Y direction from the surface side of the corresponding channels 61, 62, but not reaching the bottom surface of the channels 61, 62.

[0098] At the tail portion 78, a dividing groove 83 is formed in the portion located between the common terminal 76 and the individual terminal 82. The dividing groove 83 opens on the surface of the tail portion 78 and extends in the X direction. The dividing groove 83 separates the common terminal 76 and the individual terminal 82 respectively.

[0099] like Figures 4-6 As shown, a flexible printed circuit board 85 is pressed onto the surface of the tail portion 78. The flexible printed circuit board 85 is connected to a common terminal 76 and a separate terminal 82 on the surface of the tail portion 78. The flexible printed circuit board 85 extends upwards.

[0100] <Cover plate 54>

[0101] like Figures 2-4 As shown, the cover plate 54 is fixed to the surface of the actuator plate 53 (excluding the opposing surface) by means of adhesive bonding or the like. Specifically, the cover plate 54 is arranged with the thickness direction in the Y direction. The cover plate 54 closes the surface-side openings of each channel 61, 62 while exposing the surface of the tail portion 78. In the Z direction, the lower end surface of the cover plate 54 is arranged coplanarly with the lower end surface of the actuator plate 53.

[0102] In the cover plate 54, at a position where it overlaps with the upper end of the ejection channel 61 when viewed from the Y direction, an inlet common ink chamber (inlet flow path) 90 is formed. The inlet common ink chamber 90 extends in the X direction, for example, across each of the channels 61, 62, and has an opening on the surface of the cover plate 54.

[0103] In the inlet common ink chamber 90, an inlet slit (inlet flow path) 91 is formed at a position where it overlaps with the ejection channel 61 when viewed from the Y direction. The inlet slit 91 connects the upper end of each ejection channel 61 to the inside of the inlet common ink chamber 90. The inlet slit 91 faces the upper tangent 61b along the Y direction. Therefore, the inlet slit 91 connects to each ejection channel 61, but does not connect to each non-ejection channel 62.

[0104] like Figure 4As shown, the nozzle plate 51 is fixed to the lower end surface of the actuator plate 53 by adhesion or the like. The nozzle plate 51 is arranged with the Z direction as the thickness direction and the X direction as the length direction. In the present embodiment, the nozzle plate 51 is formed of a resin material such as polyimide with a thickness of about 50 μm. However, the nozzle plate 51 can be a single-layer structure or a laminated structure using a metal material (SUS or Ni-Pd or the like), glass, silicon, or the like, in addition to a resin material.

[0105] In the nozzle plate (ejection hole plate) 51, the above-described nozzle holes (ejection holes) 93 are formed so as to penetrate the nozzle plate 51 in the Z direction. The nozzle holes 93 are respectively formed in the nozzle plate 51 at positions opposite the discharge passages 61 in the Z direction. Further, each nozzle hole 93 is formed in a tapered shape that gradually tapers as it goes from the top to the bottom.

[0106] [Method of operation of printer 1]

[0107] Next, a case in which characters or graphics or the like are recorded on the recording medium P using the printer 1 configured as described above will be described below.

[0108] Further, as an initial state, it is assumed that the four ink tanks 15 are filled with ink of different colors from each other as shown. Figure 1 As shown, the four ink tanks 15 are filled with ink of different colors from each other. In addition, the ink in the ink tanks 15 is brought into a state of being filled into the inkjet head 5 through the ink piping 16.

[0109] In this initial state, if the printer 1 is operated, the recording medium P is sandwiched by the rollers 11, 12 of the conveyance mechanism 2, 3 and is simultaneously conveyed to the +X side. In addition, at the same time, the carriage 23 is moved in the Y direction, whereby the inkjet head 5 mounted on the carriage 23 is reciprocally moved in the Y direction.

[0110] During the reciprocating movement of the inkjet head 5, ink is appropriately discharged from each inkjet head 5 to the recording medium P. Thereby, the recording medium P can be recorded with characters or images or the like.

[0111] If the reciprocating movement of the inkjet head 5 is started by the movement of the carriage 23 (see Figure 1 ), a drive voltage is applied between the common electrode 75 and the individual electrodes 81 via the flexible printed substrate 85. At this time, the individual electrodes 81 are made to be the drive potential Vdd and the common electrode 75 is made to be the reference potential GND to apply the drive voltage between each electrode. Then, the drive wall 65 is deformed by a so-called inverse piezoelectric effect to slide in thickness, whereby it is deformed in a V-shape with the central portion in the Y direction as a starting point. That is, the drive wall 65 is deformed in a manner that the volume of the discharge passage 61 is expanded.

[0112] After the volume of each discharge passage 61 is increased, the voltage applied between the common electrode 75 and the individual electrode 81 is made zero. Then, the drive wall 65 returns to the original volume of the temporarily increased volume of the discharge passage 61. Thus, the pressure inside the discharge passage 61 increases, and the ink is pressurized. Then, a pressure wave generated due to the increase in the pressure inside the discharge passage 61 propagates toward the nozzle hole 93. As a result, the ink inside the discharge passage 61 is discharged in the form of droplets through the nozzle hole 93. The ink discharged from the nozzle hole 93 hits the recording medium P, and thus characters or images and the like can be recorded on the recording medium P.

[0113] <Manufacturing method of head chip 50>

[0114] Next, the manufacturing method of the head chip 50 described above will be briefly described. Figure 7 is a flowchart for explaining the manufacturing method of the head chip 50. Figures 8-11 is a process diagram for explaining the manufacturing method of the head chip 50. In the present embodiment, a method of manufacturing a plurality of head chips 50 at a wafer level will be described.

[0115] As shown in Figure 7 , the head chip 50 is manufactured through, for example, a first dicing process, a second dicing process, a wiring formation process, a third dicing process, a lamination process, a monolithic process, and a nozzle plate joining process.

[0116] As shown in Figure 8 , the first dicing process forms first dicing lines 110, which become the discharge passages 61 later, with respect to a drive wafer 100, which becomes the drive board 55 later. Specifically, a dicing machine is made to enter from the surface side with respect to the drive wafer 100, and the dicing machine is made to travel a predetermined amount. The length of the first dicing line 110 along the extension direction LI (the amount of travel of the dicing machine) is set to a length of about the amount of two discharge passages 61. Therefore, in the first dicing line 110, both end portions in the extension direction LI become portions that function as the upper cut portions 61b of the discharge passage 61, and the central portion in the extension direction LI becomes a portion that functions as the extension portion 61a. In the first dicing process, the above-described operation is repeatedly performed with respect to the drive wafer 100 at intervals in the extension direction LI and a cross direction (hereinafter, referred to as a cross direction L2) that intersects the extension direction LI.

[0117] As shown in Figure 9As shown, in the second dicing process, a second dicing line 111 is formed, which subsequently becomes a non-ejection channel 62. Specifically, the dicing machine is brought into the portion located on both sides of the first dicing line 110 in the X direction relative to the drive wafer 100, and the dicing machine travels a predetermined amount. The length of the second dicing line 111 along the extension direction L1 (the amount of travel by the dicing machine) is set to approximately the length of two non-ejection channels 61. Therefore, in the second dicing line 111, the two ends of the extension direction L1 become portions that function as upper cut portions 62b of the non-ejection channel 62, and the central portion of the extension direction L1 becomes a portion that functions as an extension portion 62a. In addition, the second dicing line 111 is formed with a half-pitch offset relative to the first dicing line 110. That is, the second dicing line 111 is formed such that the ends of the extension direction L1 in the second dicing line 111 and the central portion of the extension direction L1 in the first dicing line 110 are arranged at the same position in the extension direction L1.

[0118] In the wiring formation process, common wiring 71 and individual wiring 72 are formed on the driver wafer 100. Specifically, electrode material is deposited from the surface side and back side of the driver wafer 100 by means of oblique evaporation or the like. As a result, wiring 71 and 72 are formed on the surface of the driver wafer 100 or the inner surface of each dicing line 110, 111 by a mask pattern (not shown).

[0119] like Figure 10 As shown, in the third dicing process, a third dicing line 113 is formed, which will later become a dividing groove 83. Specifically, in the drive wafer 100, the dicing machine enters the drive wafer 100 from the surface side relative to the portion between adjacent first dicing lines 110 located in the extension direction L1, and the dicing machine travels along the intersecting direction L2.

[0120] In the lamination process, a back wafer (not shown), which will later become a backplate 56, is laminated onto the back side of the driver wafer 100. Additionally, a cover wafer (not shown), which will later become a cover plate 54, is laminated onto the surface side of the driver wafer 100. Thus, a wafer bond consisting of the driver wafer 100, the back wafer, and the cover wafer is formed.

[0121] like Figure 11 As shown, in the monolithization process, the wafer assembly is divided into individual chip heads 50. Specifically, the dicing machine is positioned at the center of the wafer assembly along the extension direction L1 in the first dicing line 110 (see reference). Figure 10 Q1), the portion located between adjacent first cutting lines 110 in the extension direction L1 (refer to) Figure 10 The wafer bonding assembly (Q2) is cut along the intersecting direction L2. This forms multiple chip bonding assemblies 109, each consisting of a cut-out of the actuator plate 53 and cover plate 54.

[0122] In the nozzle plate joining step, the nozzle plate 51 is joined to the chip joint body 109 cut in the singulation step.

[0123] The head chip 50 is manufactured by the above.

[0124] Accordingly, the head chip 50 of the present embodiment is configured such that the non-ejection passage 62 terminates at a position separated from the lower end surface of the actuator plate 53, and the ejection passage 61 opens on the lower end surface of the actuator plate 53.

[0125] According to this configuration, the non-ejection passage 62 is not open on the lower end surface of the actuator plate 53, and thus it is possible to suppress the ink in the ejection passage 61 from entering the non-ejection passage 62 through a minute gap or the like unintentionally formed between the actuator plate 53 and the nozzle plate 51.

[0126] Accordingly, it is possible to provide a head chip 50 that suppresses corrosion or short circuit of an electrode formed on the inner surface of the non-ejection passage 62, has excellent electrical reliability, and seeks to improve durability.

[0127] Furthermore, it is possible to ease the surface properties required of the lower end surface of the actuator plate 53, and thus it is possible to seek to improve manufacturing efficiency or improve yield. In particular, with the edge-shooter type, the lower end surface of the actuator plate 53 (the opening surface of the ejection passage 61) is formed by the cutting surface of a cutting machine or the like, and thus there is a possibility that unevenness or undulations or the like will be generated on the lower end surface, and it is difficult to highly accurately surface the surface properties. Even in such a case, it is possible to not only reduce the burden imposed in the joining step of the nozzle plate 51, but also suppress the inflow of ink into the non-ejection passage 62.

[0128] In the inkjet head 5 and the printer 1 of the present embodiment, the above-described head chip 50 is provided, and thus it is possible to provide an inkjet head 5 and a printer 1 that have excellent reliability.

[0129] (Modified Example)

[0130] In the above-described embodiment, a configuration in which the Z-directional dimension of the occlusion portion 67 gradually increases from the surface side to the back surface side of the drive plate 55 was described, but the configuration is not limited to this. For example, as shown in FIG. 17, a configuration in which the Z-directional dimension of the occlusion portion 67 gradually increases from the back surface side toward the surface side of the drive plate 55 can also be used. That is, in the present modified example, the occlusion inner surface portion 67a is formed as an inclined surface that extends upward as it goes from the back surface side toward the surface side. Figure 12

[0131] In addition, it can also be as shown in FIG. 18, for example, a configuration in which the Z-directional dimension of the occlusion portion 67 is constant from the back surface side to the surface side of the drive plate 55. Figure 13 ​As shown, the Z-directional dimension of the occlusion portion 67 is configured to gradually increase toward the central portion in the Y-direction from the surface side and the back side of the drive plate 55. Specifically, the occlusion inner surface portion 67a has a first inclined surface 130a extending upward toward the central portion in the Y-direction from the surface side of the drive plate 55, and a second inclined surface 130b extending upward toward the central portion in the Y-direction from the back side of the drive plate 55, which is connected to the first inclined surface 130a. With the occlusion portion 67 of the present modification example, the cutting machine can be caused to enter from both surfaces of the drive wafer 100 in the second cutting process described above to form.

[0132] In the present modification example, compared to a case where the cutting machine is caused to enter from one surface with respect to the actuator plate 53 to form the non-discharge passage 62, for example, the maximum dimension in the Z-direction in the occlusion portion 67 (the maximum distance between the occlusion inner surface portion 67a and the occlusion outer surface portion 67b) can be suppressed. As a result, the opposing regions in the X-direction of the discharge passage 61 and the non-discharge passage 62 (the Z-directional dimension in the drive wall 65) can be ensured. Therefore, the opposing area of the common electrode 75 and the individual electrode 81 can be ensured, and thus the pump stroke can be ensured, increasing the deformation volume of the drive wall 65 at the time of ink discharge. With the increase in the deformation volume of the drive wall 65, it is possible to reduce the applied voltage for performing the same discharge. In addition, an improvement in discharge performance such as an improvement in discharge speed can be expected with the same applied voltage.

[0133] (Second Embodiment)

[0134] In the present embodiment, the head chip 150 is different from the above-described embodiments in that it is of a circulation type. Figure 14 FIG. 16 is a sectional view showing a section along the discharge passage 61 in the head chip 150 according to the second embodiment.

[0135] In addition to the nozzle plate 51, the actuator plate 53, and the cover plate (flow path member) 54, Figure 14 The head chip 150 shown has a flow path plate (flow path member) 151 and a return plate (intermediate plate) 152.

[0136] The flow path plate 151 is laminated to the surface of the cover plate 54. The inlet manifold (inlet flow path) 155 and the outlet manifold (outlet flow path) 156 are formed in the flow path plate 151. The inlet manifold 155 is formed in the portion of the flow path plate 151 that laminates with the inlet common ink chamber 90 when viewed in the Y-direction. Specifically, the inlet manifold 155 is opened on the back surface of the flow path plate 151 and extends in the X-direction. The inlet manifold 155 communicates with the inlet common ink chamber 90 through the back surface side opening portion. On the other hand, the inlet manifold 155 is connected to the ink tank 15 through, for example, an inlet port (not shown) provided at one end portion in the X-direction in the flow path plate 151.

[0137] The outlet manifold 156 is opened on the lower end surface of the flow path board 151 and extends in the X direction. The outlet manifold 156 is connected to the ink tank 15 through an outlet port (not shown) provided in the other end portion in the X direction in the flow path board 151, for example.

[0138] Figure 15 is a cross-sectional view corresponding to XV-XV line of Figure 14

[0139] As shown in Figure 14 , Figure 15 The return board 152 is disposed between the actuator board 53 and the nozzle board 51. Specifically, the upper end surface of the return board 152 is integrally joined with the actuator board 53, the cover board 54, and the lower end surface of the flow path board 151. The nozzle board 51 is joined to the lower end surface of the return board 152.

[0140] In the return board 152, a circulation path (communication path) 157 is formed at a position overlapping with the discharge passage 61 when viewed in the Z direction. The circulation path 157 communicates the corresponding discharge passage 61 and nozzle hole 93 with each other and the discharge passage 61 and outlet manifold 156 with each other. The circulation path 157 penetrates the return board 152 in the Z direction and extends in the Y direction. Each circulation path 157 communicates with the corresponding discharge passage 61 at the -Y side end portion. Each circulation path 157 communicates with the outlet manifold 156 at the +Y side end portion. Further, it is preferable that the X direction width of the circulation path 157 is larger than the X direction width of the discharge passage 61.

[0141] In the head chip 150 of the present embodiment, the ink flowing in the inlet manifold 155 flows into the discharge passage 61 through each inlet slit 91 after passing through the inlet common ink chamber 90. The ink flowing in the discharge passage 61 flows into the circulation path 157. A part of the ink flowing in each circulation path 157 is discharged from the nozzle hole 93 due to the pressure increase in the discharge passage 61 accompanying the thickness sliding deformation of the drive wall 65. On the other hand, the remaining ink flowing in each circulation path 157 flows into the outlet manifold 156. The ink flowing into the outlet manifold 156 returns to the ink tank 15 through the outlet port. Thereafter, the ink that has returned to the ink tank 15 is supplied to the head chip 150 again.

[0142] In the head chip 150 of the present embodiment, the return board 152 having the circulation path 157 is disposed between the actuator board 53 and the nozzle board 51.

[0143] ​According to this configuration, the non-discharge passage 62 is not opened on the lower end surface of the actuator plate 53, and thus the size of the circulation path 157 in the X direction can be ensured to be large. Therefore, it is easy to allow a positional shift in the X direction, for example, between the nozzle hole 93 and the circulation path 157 or between the discharge passage 61 and the circulation path 157. Thus, the flow path cross-sectional area of the communication portion between the nozzle hole 93 and the circulation path 157 or between the discharge passage 61 and the circulation path 157 can be ensured.

[0144] In the head chip 150 of the present embodiment, the size of the circulation path 157 in the X direction can be ensured to be large, and thus the flow path cross-sectional area of the circulation path 157 can be easily ensured. In this case, the flow rate of the ink flowing in the circulation path 157 can be increased, and thus it is possible to suppress bubble clogging at the nozzle hole 93 or to increase the discharge amount of the ink through the nozzle hole 93. In addition, it is easy to dissipate a pressure fluctuation generated in one discharge passage 61, for example, at the time of ink discharge, in the circulation path 157. Thus, even in the case where a plurality of discharge passages 61 are communicated through the outlet manifold 156, it is possible to suppress the propagation of the pressure fluctuation generated in one discharge passage 61 to other discharge passages 61 through the outlet manifold 156 and the circulation path 157, so-called crosstalk.

[0145] On the other hand, the size of the circulation path 157 in the X direction can be ensured to be large, and thus it is possible to ensure the flow path cross-sectional area of the circulation path 157 while suppressing the thickness (size in the Z direction) of the return plate 152. Therefore, it is possible to effectively propagate the pressure fluctuation generated in the discharge passage 61 at the time of ink discharge up to the nozzle hole 93.

[0146] As a result, it is possible to improve the discharge performance.

[0147] Further, if the circulation path 157 is a configuration that respectively communicates one discharge passage 61 and the outlet manifold 156, it can also extend, for example, in a direction intersecting the Y direction. In addition, in the above-described embodiments, the configuration in which the inlet manifold 155 and the outlet manifold 156 are formed in one flow path plate 151 is described, but is not limited to this configuration. For example, a flow path plate 151 having the inlet manifold 155 can be provided on the surface side of the cover plate 54 and a flow path plate having the outlet manifold 156 can be provided on the back surface side of the back plate 56.

[0148] (Third Embodiment)

[0149] The head chip 200 according to the present embodiment differs from the above-described embodiments in that the circulation path 201 is formed in the cover plate 54. Figure 16 is a cross-sectional view showing a cross section along the discharge passage 61 in the head chip 200 according to the third embodiment.

[0150] InFigure 16 In the illustrated head chip 200, a circulation path 201 is formed at the lower end of the cover plate 54. Multiple circulation paths 201 are provided at intervals along the X direction, corresponding to each ejection channel 61. The circulation path 201 extends through the cover plate 54 along the Y direction and is open on the lower end face of the cover plate 54. In the illustrated example, regarding the circulation path 201, the flow path cross-sectional area (the area orthogonal to the Y direction) is formed uniformly along its entire length and extends linearly along the Y direction.

[0151] The -Y side end of each circulation path 201 is connected to the discharge channel 61. On the other hand, the +Y side end of each circulation path 201 is uniformly connected to the outlet manifold 156. Furthermore, if the circulation path 201 is configured to connect the discharge channel 61 and the outlet manifold 156 respectively, it may extend, for example, in a direction that intersects with respect to the Y direction.

[0152] Based on this configuration, similar to the second embodiment described above, the non-dispensing channel 62 is not open on the lower end face of the actuator plate 53, thus easily ensuring the flow path cross-sectional area of ​​the circulation path 201. Therefore, it is possible to suppress air bubble blockage at the nozzle orifice 93 or increase the amount of ink dispensed through the nozzle orifice 93.

[0153] In addition, it is easy to dissipate pressure variations, such as those generated in an ejection channel 61 during ink ejection, within the circulation path 201, thereby suppressing crosstalk.

[0154] (Modified Example)

[0155] In the above embodiment, a configuration in which the cross-sectional area of ​​the circulation path 201 is formed uniformly along its entire length has been described, but the embodiment is not limited to this configuration. For example, it could also be as follows: Figure 17 As shown, the cross-sectional area of ​​the circulation path 201 gradually increases toward the outlet manifold 156.

[0156] Based on this configuration, the cross-sectional area of ​​the circulation path 201 can be gradually increased, thereby suppressing air bubble blockage at the nozzle orifice 93 or increasing the amount of ink ejected through the nozzle orifice 93.

[0157] In addition, it is easy to dissipate pressure variations, such as those generated in an ejection channel 61 during ink ejection, within the circulation path 201, thereby suppressing crosstalk.

[0158] In the above embodiment, the configuration in which the circulation path 201 is open at the lower end face of the cover plate 54 has been described, but the configuration is not limited to this. For example, it may also be as follows: Figure 18As shown, the circulation path 201 extends along the Y direction through the upper portion of the cover plate 54 from the lower end face. In this case, the circulation path 201 is not open on the lower end face of the cover plate 54, thus the entire lower end face of the cover plate 54 becomes a flat, continuous surface. Therefore, it becomes easier to ensure the area of ​​the lower end face of the cover plate 54 that engages with the nozzle plate 51, and the bonding strength can be ensured. As a result, the durability of the head chip 200 is easily ensured.

[0159] Figure 19 The head chip 200 shown is Figure 12 The configuration shown is similar in that the dimension of the blocking portion 67 in the Z direction gradually increases from the back side of the drive plate 55 toward the surface side.

[0160] Based on this configuration, it is easy to ensure the area of ​​the portion on the surface of the actuator plate 53 located between the inner surface portion 67a of the blockage and the lower end face of the actuator plate 53. Therefore, the flow path cross-sectional area of ​​the circulation path 201 can be maximized. As a result, the circulation flow rate of ink within the head chip 200 can be increased, thereby suppressing air bubble blockage at the nozzle orifice 93 or increasing the amount of ink ejected through the nozzle orifice 93.

[0161] In addition, it is easy to dissipate pressure variations, such as those generated in an ejection channel 61 during ink ejection, within the circulation path 201, thereby suppressing crosstalk.

[0162] Furthermore, in the above embodiment, the configuration in which the inlet manifold 155 and the outlet manifold 156 are formed on a single flow path plate 151 has been described, but the configuration is not limited to this. For example, the flow path plate 151 with the inlet manifold 155 may be provided on the surface side of the cover plate 54, and the flow path plate with the outlet manifold 156 may be provided on the back side of the back plate 56. In this case, the circulation path 201 is formed on the back plate 56.

[0163] (Fourth Implementation)

[0164] In this embodiment, the so-called side-firing head chip 300 adopts the configuration involved in this disclosure, which differs from the first embodiment. Figure 20 This is a cross-sectional view showing a section along the ejection channel 301 in the head chip 300 according to the fourth embodiment.

[0165] exist Figure 20 In the head chip 300 shown, the ejection channel 301 is formed in a curved shape that protrudes downwards (towards the -Z side) when viewed from the X direction. The ejection channel 301 is formed, for example, by having a circular plate-shaped cutter enter from below (towards the +Z side) the actuator plate 53. Specifically, the ejection channel 301 has upper cut portions 301a at both ends in the Y direction and through portions 301b between each upper cut portion 301a.

[0166] The upper cut portion 301a is a circular arc shape extending from the X direction, for example, following the curvature radius of a cutting machine. The upper cut portion 301a curves toward the back side while extending as it departs from the through portion 301b in the Y direction.

[0167] The through portion 301b penetrates the actuator plate 53 in the Z direction.

[0168] Figure 21 is a cross-sectional view showing a cross section along the non-ejection passage 302 in the head chip 300 according to the fourth embodiment.

[0169] As shown in Figure 21 , the non-ejection passage 302 is adjacent to the ejection passage 301 in the X direction across the drive wall 65. The non-ejection passage 302 extends in a straight line in the Y direction in the actuator plate 53. The non-ejection passage 302 has a deep groove portion 302a and a shallow groove portion 302b.

[0170] The deep groove portion 302a is formed in the -Y side end portion (the portion located on the -Y side with respect to the ejection passage 301) in the actuator plate 53. The deep groove portion 302a penetrates the actuator plate 53 in the Z direction.

[0171] The shallow groove portion 302b is connected to the +Y side from the deep groove portion 302a. The shallow groove portion 302b is open at the upper surface of the actuator plate 53 and terminates at a position that departs upward with respect to the lower surface of the actuator plate 53. That is, the shallow groove portion 302b is not open at the lower surface of the actuator plate 53. In the actuator plate 53, the portion between the bottom surface of the shallow groove portion 302b and the lower surface of the actuator plate 53 constitutes an occlusion portion 303. The occlusion portion 303 cuts off the inside and outside of the non-ejection passage 302 in the Z direction.

[0172] In the present embodiment, the occlusion portion 303 coincides with the ejection passage 301 in the X direction. Furthermore, the occlusion portion 303 can be formed in at least a region that coincides with the through portion 301b.

[0173] The cover plate 54 is provided with an inlet common ink chamber 310 and an outlet common ink chamber 311, respectively.

[0174] The inlet common ink chamber 310 is formed, for example, at a position overlapping the -Y side end portion of the ejection passage 301 in plan view. The inlet common ink chamber 310 extends in the X direction over the length of the passages 301, 302, for example, and is open at the upper surface of the cover plate 54.

[0175] The outlet common ink chamber 311 is formed, for example, at a position overlapping the +Y side end portion of the ejection passage 301 in plan view. The outlet common ink chamber 311 extends in the X direction over the length of the passages 301, 302, and is open at the upper surface of the cover plate 54.

[0176] In the inlet common ink chamber 310, an inlet slit 315 is formed at a position overlapping the ejection passage 301 in plan view. The inlet slit 315 respectively communicates between the -Y side end portion of each ejection passage 301 and the inside of the inlet common ink chamber 310.

[0177] In the outlet common ink chamber 311, an outlet slit 316 is formed at a position corresponding to the ejection passage 301. The outlet slit 316 respectively communicates between the +Y side end portion of each ejection passage 301 and the inside of the outlet common ink chamber 311. Thus, the inlet slit 315 and the outlet slit 316 respectively communicate with each ejection passage 301, while not communicating with the non-ejection passage 302.

[0178] In the present embodiment, the non-ejection passage 302 is also not opened on the lower surface of the actuator plate 53, so that entry of ink in the ejection passage 301 into the non-ejection passage 302 through a minute gap or the like unintentionally formed between the actuator plate 53 and the nozzle plate 51 can be suppressed.

[0179] Thus, a head chip 300 can be provided which suppresses corrosion or short circuit of the electrode formed on the inner surface of the non-ejection passage 302, is excellent in electrical reliability, and seeks to improve durability.

[0180] Further, in the above-described embodiments, a configuration in which the nozzle plate 51 and the lower surface of the actuator plate 53 are directly joined has been described, but the configuration is not limited to this. As shown in FIG. 12, for example, an intermediate plate 320 can be disposed between the actuator plate 53 and the nozzle plate 51. Figure 22 The intermediate plate 320 is fixed to the lower surface of the actuator plate 53 by adhesion or the like. The intermediate plate 320 is also formed of a piezoelectric material such as PZT as with the actuator plate 53. However, the intermediate plate 320 can also be formed of a material other than a piezoelectric material (for example, a non-conductive material such as polyimide or alumina).

[0181] In the intermediate plate 320, a communication hole 321 is formed at a portion overlapping the through portion 301b of each ejection passage 301 in plan view. The communication hole 321 respectively communicates between the lower surface side of the actuator plate 53 and the inside of the corresponding through portion 301b of the ejection passage 301. The Y direction dimension in the communication hole 321 is shorter than the through portion 301b. On the other hand, the X direction dimension in the communication hole 321 is larger than the through portion 301b, and becomes equal to the maximum inner diameter of the nozzle hole 93.

[0182] In the present embodiment, the non-ejection passage 302b is also not opened on the lower surface of the actuator plate 53, and thus the size of the communication hole 321 in the X direction can be ensured to be large. Therefore, it is easy to allow a positional shift in the X direction between the nozzle hole 93 and the communication hole 321 or between the ejection passage 301 and the communication hole 321. Thus, the flow cross-sectional area of the communication portion between the nozzle hole 93 and the communication hole 321 or between the ejection passage 301 and the communication hole 321 can be ensured.

[0183] (Other modifications)

[0184] Furthermore, the technical scope of the present disclosure is not limited to the above-described embodiments, and various modifications can be added within the scope of the object of the present disclosure.

[0185] For example, in the above-described embodiments, an inkjet printer 1 is exemplified as one example of a liquid ejection recording device, but is not limited to a printer. For example, it can be a facsimile or a print-on-demand machine, or the like.

[0186] In the above-described embodiments, a configuration in which the inkjet head is moved with respect to the recording medium at the time of printing (so-called shuttle machine) is exemplified, but is not limited to this configuration. The configuration according to the present disclosure can also be adopted in a configuration in which the recording medium is moved with respect to the inkjet head in a state in which the inkjet head is fixed (so-called fixed head machine).

[0187] In the above-described embodiments, a case in which the recording medium P is paper is exemplified, but is not limited to this configuration. The recording medium P is not limited to paper, and can be a metal material or a resin material, and can be a food or the like.

[0188] In the above-described embodiments, a configuration in which the liquid ejection head is mounted on the liquid ejection recording device is exemplified, but is not limited to this configuration. That is, the liquid ejected from the liquid ejection head is not limited to a liquid that hits the recording medium, and can be, for example, a medical liquid that is mixed in a medicine, or a food additive such as a seasoning or a perfume that is added to a food, or an aroma that is ejected into the air, or the like.

[0189] In the above-described embodiments, a configuration in which the Z direction coincides with the direction of gravity is exemplified, but is not limited to this configuration, and the Z direction can also be made to follow the horizontal direction.

[0190] In the above-described embodiments, a configuration in which the first direction coincides with the Z direction and the second direction coincides with the X direction is exemplified, but is not limited to this configuration. The first direction and the second direction can also be determined to be different from the X direction and the Z direction.

[0191] Moreover, the components in the above-described embodiments can be appropriately replaced with well-known components without departing from the spirit of the present disclosure, and the above-described various modifications can be appropriately combined.

[0192] Symbol explanation

[0193] 1 …… Inkjet printer (liquid ejection recording apparatus)

[0194] 5 …… Inkjet head (liquid ejection head)

[0195] 50 …… Head chip

[0196] 51 …… Nozzle plate (ejection hole plate)

[0197] 53 …… Actuator plate

[0198] 51 …… Nozzle plate (ejection hole plate)

[0199] 54 …… Cover plate (flow path member)

[0200] 61 …… Discharge passage (ejection passage)

[0201] 62 …… Non-discharge passage (non-ejection passage)

[0202] 90 …… Inlet common ink chamber (inlet flow path)

[0203] 91 …… Inlet slit (inlet flow path)

[0204] 93 …… Nozzle hole (ejection hole)

[0205] 130a …… First inclined surface

[0206] 130b …… Second inclined surface

[0207] 150 …… Head chip

[0208] 151 …… Flow path plate (flow path member)

[0209] 152 …… Return plate (intermediate plate)

[0210] 155 …… Inlet manifold (inlet flow path)

[0211] 156 …… Outlet manifold (outlet flow path)

[0212] 157 …… Circulation path (communication path)

[0213] 200 …… Head chip

[0214] 201 …… Circulation path (communication path)

[0215] 300 …… Head chip

[0216] 301 …… Discharge passage (ejection passage)

[0217] 302 …… Non-discharge passage (ejection passage)

[0218] 310 …… Inlet common ink chamber (inlet flow path)

[0219] 311 …… Outlet common ink chamber (outlet flow path)

[0220] 315 …… Inlet slit (inlet flow path)

[0221] 316 …… Outlet slit (outlet flow path)

[0222] 320 …… Intermediate plate

[0223] 321 …… Communication hole (communication path)

Claims

1. A head chip, comprising: an actuator plate in which ejection passages and non-ejection passages extending in a first direction are alternately arranged in a second direction intersecting the first direction; an ejection hole plate having ejection holes communicating with the ejection passages and facing the actuator plate; and a blocking portion disposed between the non-ejection passages and the ejection hole plate, the non-ejection passages being terminated at positions separated from an opposing surface in the actuator plate adjacent to the ejection hole plate, the opposing surface being a surface in the actuator plate facing the first direction, by the blocking portion formed integrally with the actuator plate, the ejection passages being opened on the opposing surface. An intermediate plate is disposed between the actuator plate and the ejection hole plate, the intermediate plate being formed with communication passages communicating the ejection passages and the ejection holes, respectively.

3. The head chip according to claim 2, wherein a flow path member facing a surface in the actuator plate other than the opposing surface is provided, the flow path member comprising: an inlet flow path communicating with the plurality of ejection passages; and an outlet flow path communicating with the plurality of communication passages collectively.

4. The head chip according to claim 1, wherein the head chip comprises a flow path member superimposed on a thickness direction in the actuator plate intersecting the second direction as viewed in the first direction, the flow path member comprising: a circulation path formed in a portion between the non-ejection passages and the opposing surface in the first direction and communicating with the ejection passages, respectively; an inlet flow path formed in a portion on a side opposite to the opposing surface in the first direction with respect to the circulation path and communicating with the ejection passages; and an outlet flow path communicating with the plurality of circulation paths collectively.

2. The head chip according to claim 1, wherein, The circulation path has a flow path cross-sectional area that increases away from the ejection passages. An end surface of the opposing surface side in the non-ejection passages is formed as an inclined surface extending in a direction away from the flow path member in the thickness direction as toward the opposing surface in the first direction. The circulation path is provided at a position away from the opposing surface in a portion between the non-ejection passages and the opposing surface in the first direction in the flow path member.

8. The head chip according to any one of claims 1 to 5, wherein the end surface of the opposing surface side in the non-ejection passages comprises: a first inclined surface extending in a direction away from the opposing surface in the first direction as away from a first surface in the actuator plate facing a thickness direction intersecting the second direction as viewed in the first direction; and a second inclined surface extending in a direction away from the opposing surface in the first direction as away from a second surface in the actuator plate in a position opposite to the first surface in the thickness direction and joined to the first inclined surface.

9. A liquid ejection head comprising the head chip according to any one of claims 1 to 8.

10. A liquid ejection recording apparatus comprising the liquid ejection head according to claim 9. ​ ​ ​ ​ ​ ​ 5. The head chip of claim 4, wherein, ​ 6. The head chip according to claim 4 or claim 5, wherein, ​ 7. The head chip according to claim 4 or claim 5, wherein, ​ ​ ​ ​ ​ ​ ​ ​

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