Liquid jet head and liquid jet recording apparatus

Abstract

To provide a liquid jet head etc. capable of easily improving reliability.SOLUTION: A liquid jet head according to an embodiment of the present disclosure includes: a jet section including a plurality of nozzles configured to jet a liquid; a drive board having a first surface on which one or multiple drive devices for outputting a drive signal for jetting the liquid from the nozzles to the jet section are disposed; a heat radiation member for cooling the drive devices, the heat radiation member disposed at the first surface side on the drive board; a pressing member which is disposed at a second surface side opposed to the first surface in the drive board and configured to press the drive board against the heat radiation member; and a fixation part configured to fix a part of the pressing member to the drive board. An arrangement area of the drive devices extends along a first direction in the first surface, and the fixation part is disposed in a region along a second direction perpendicular to the first direction in the first surface with reference to arrangement positions of the drive devices.SELECTED DRAWING: Figure 5

Description

Technical Field

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

Background Art

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

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In such a liquid ejection head, generally, improvement in reliability is required. It is desirable to provide a liquid ejection head and a liquid ejection recording apparatus capable of improving reliability.

Means for Solving the Problems

[0005] A liquid ejection head according to an embodiment of the present disclosure includes an ejection unit having a plurality of nozzles for ejecting a liquid, one or a plurality of drive devices for outputting a drive signal for ejecting the liquid from the nozzles to the ejection unit, a drive substrate disposed on a first surface, a heat dissipation member disposed on the first surface side of the drive substrate for cooling the drive devices, a pressing member disposed on the second surface side of the drive substrate facing the first surface for pressing the drive substrate against the heat dissipation member, and a fixing portion for fixing a part of the pressing member to the drive substrate. The arrangement region of the drive devices extends along a first direction in the first surface, and the fixing portion is disposed in a region along a second direction orthogonal to the first direction in the first surface with reference to the arrangement position of the drive devices.

[0006] The liquid injection recording apparatus according to one embodiment of the present disclosure includes the liquid injection head according to one embodiment of the present disclosure.

Effects of the Invention

[0007] According to the liquid injection head and the liquid injection recording apparatus according to one embodiment of the present disclosure, it is possible to improve reliability.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

Mode for Carrying Out the Invention

[0009] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. The description will be made in the following order. 1. Embodiment (Example of a liquid ejection head having fixed parts of various configurations) 2. Modifications Modifications 1 and 2 (Configuration examples when the number of drive devices is changed) 3. Other modifications

[0010] <1. Embodiment> [Schematic Configuration of Printer 5] FIG. 1 shows a schematic configuration example of a printer 5 as a liquid ejection recording apparatus according to an embodiment of the present disclosure in a block diagram. FIG. 2 schematically shows a schematic configuration example of an inkjet head 1 as the liquid ejection head shown in FIG. 1 in a perspective view. FIG. 3 schematically shows a configuration example of the inkjet head 1 shown in FIG. 2 in a cross-sectional view (Y-Z cross-sectional view).

[0011] In each drawing used in the description of this specification, the scale of each member is appropriately changed in order to make each member recognizable in size.

[0012] The printer 5 is an inkjet printer that performs recording (printing) of images, characters, etc. on a recording medium (for example, the recording paper P shown in FIG. 1) using ink 9 described later. As shown in FIG. 1, this printer 5 includes an inkjet head 1, a print control unit 2, and an ink tank 3.

[0013] Note that the inkjet head 1 corresponds to a specific example of the "liquid ejection head" in the present disclosure, and the printer 5 corresponds to a specific example of the "liquid ejection recording apparatus" in the present disclosure. Further, the ink 9 corresponds to a specific example of the "liquid" in the present disclosure.

[0014] (A. Printing control unit 2) The printing control unit 2 supplies various kinds of information (data) to the inkjet head 1. Specifically, as shown in FIG. 1, the printing control unit 2 supplies a printing control signal Sc to the inside of the inkjet head 1 (such as a drive device 41 described later). Note that the printing control signal Sc includes, for example, image data, a discharge timing signal, and a power supply voltage for operating the inkjet head 1.

[0015] (B. Ink tank 3) The ink tank 3 is a tank that houses the ink 9 inside. The ink 9 in the ink tank 3 is supplied to the inside of the inkjet head 1 (a jetting unit 11 described later) via an ink supply tube 30 as shown in FIG. 1. Note that such an ink supply tube 30 is constituted by, for example, a flexible hose having flexibility.

[0016] (C. Inkjet head 1) As shown by the dashed arrow in FIG. 1, the inkjet head 1 is a head that jets (discharges) droplet-like ink 9 onto the recording paper P from a plurality of nozzle holes Hn described later to perform recording of an image, characters, etc. The inkjet head 1 includes, for example, as shown in FIGS. 2 and 3, one jetting unit 11, one I / F (interface) substrate 12, four flexible substrates 13a, 13b, 13c, 13d, and two cooling units 141, 142.

[0017] Here, the flexible substrates 13a, 13b, 13c, 13d (flexible substrate 13 to be described later) each correspond to a specific example of the "drive substrate" in the present disclosure. Also, the cooling units 141, 142 (cooling unit 14 to be described later) each correspond to a specific example of the "heat dissipation member" in the present disclosure.

[0018] (C-1. I / F Substrate 12) As shown in FIGS. 2 and 3, the I / F substrate 12 includes two connectors 10, four connectors 120a, 120b, 120c, 120d, and a circuit arrangement region 121.

[0019] As shown in FIG. 2, the connector 10 is a portion (connector portion) for inputting the aforementioned print control signal Sc supplied from the print control unit 2 toward the inkjet head 1 (each flexible substrate 13a, 13b, 13c, 13d to be described later).

[0020] The connectors 120a, 120b, 120c, 120d are each a portion (connector portion) for electrically connecting between the I / F substrate 12 and the flexible substrates 13a, 13b, 13c, 13d.

[0021] The circuit arrangement region 121 is a region on the I / F substrate 12 where various circuits are arranged. Note that such a circuit arrangement region may also be provided in other regions on the I / F substrate 12.

[0022] (C-2. Injection Unit 11) As shown in FIG. 1, the injection unit 11 has a plurality of nozzle holes Hn and is a portion for injecting the ink 9 from these nozzle holes Hn. Such injection of the ink 9 is performed according to a drive signal Sd (drive voltage Vd) supplied from a drive device 41 to be described later on each of the flexible substrates 13a, 13b, 13c, 13d (see FIG. 1).

[0023] As shown in FIG. 1, such an injection unit 11 is configured to include an actuator plate 111 and a nozzle plate 112.

[0024] (Nozzle plate 112) The nozzle plate 112 is a plate made of a film material such as polyimide or a metal material, and as shown in FIG. 1, has the plurality of nozzle holes Hn described above. These nozzle holes Hn are formed side by side at a predetermined interval and are, for example, circular in shape. Note that each of these nozzle holes Hn corresponds to a specific example of the "nozzle" in the present disclosure.

[0025] Specifically, in the example of the injection unit 11 shown in FIG. 2, the plurality of nozzle holes Hn in the nozzle plate 112 are constituted by a plurality of nozzle rows (four nozzle rows) respectively arranged along the column direction (X-axis direction). Further, these four nozzle rows are arranged side by side along the direction orthogonal to the column direction (Y-axis direction).

[0026] (Actuator plate 111) The actuator plate 111 is a plate made of a piezoelectric material such as PZT (lead zirconate titanate), for example. A plurality of channels (pressure chambers) are provided in the actuator plate 111. These channels are portions for applying pressure to the ink 9 and are arranged side by side at a predetermined interval so as to be parallel to each other. Each channel is defined by a drive wall (not shown) made of a piezoelectric body and has a concave groove portion in a cross-sectional view.

[0027] Such channels include a discharge channel for discharging the ink 9 and a dummy channel (non-discharge channel) that does not discharge the ink 9. In other words, while the discharge channel is filled with the ink 9, the dummy channel is not filled with the ink 9. Note that the filling of the ink 9 into each discharge channel is performed, for example, via a flow path (common flow path) that communicates in common with such each discharge channel. Further, each discharge channel communicates individually with the nozzle hole Hn in the nozzle plate 112, while each dummy channel does not communicate with the nozzle hole Hn. These discharge channels and dummy channels are arranged alternately side by side along the column direction (X-axis direction) described above.

[0028] Further, drive electrodes are provided on the opposing inner surfaces of the drive walls described above. On this drive electrode, there exist a common electrode (common electrode) provided on the inner surface facing the discharge channel and an active electrode (individual electrode) provided on the inner surface facing the dummy channel. Between these drive electrodes and a drive device 41 described later, they are electrically connected via each flexible substrate 13a, 13b, 13c, 13d. Thereby, the drive voltage Vd (drive signal Sd) described above is applied from the drive device 41 to each drive electrode via each flexible substrate 13a, 13b, 13c, 13d (see FIG. 1).

[0029] (C-3. Flexible substrates 13a, 13b, 13c, 13d) Flexible substrates 13a, 13b, 13c, and 13d are each substrates (drive substrates) that electrically connect between the I / F substrate 12 and the ejection unit 11, as shown in FIGS. 2 and 3. Each of these flexible substrates 13a, 13b, 13c, and 13d is configured to individually control the ejection operation of the ink 9 for each of the four nozzle rows in the nozzle plate 112 described above. Also, for example, as indicated by reference numerals P1a, P1b, P1c, and P1d in FIG. 3, in the vicinity of the connection portion of each flexible substrate 13a, 13b, 13c, and 13d to the ejection unit 11 (near the pressure bonding electrode 433), each flexible substrate 13a, 13b, 13c, and 13d is configured to be bent. Note that between the pressure bonding electrode 433 and the ejection unit 11, electrical connection is made to each other by thermocompression bonding using, for example, an ACF (Anisotropic Conductive Film).

[0030] On each of such flexible substrates 13a, 13b, 13c, and 13d (on the surface S1), drive devices 41 are individually mounted (see FIG. 3). Each of these drive devices 41 is a device that outputs a drive signal Sd (drive voltage Vd) for ejecting the ink 9 from the nozzle holes Hn in the corresponding nozzle row in the ejection unit 11. Therefore, such a drive signal Sd is output from each of the flexible substrates 13a, 13b, 13c, and 13d to the ejection unit 11. Note that each of such drive devices 41 is configured by, for example, an ASIC (Application Specific Integrated Circuit) or the like.

[0031] Also, each of these drive devices 41 is to be cooled by the aforementioned cooling units 141 and 142. Specifically, as shown in FIG. 3, a cooling unit 141 is fixedly disposed between the drive devices 41 on the flexible substrates 13a and 13b, and each drive device 41 is cooled by pressing the cooling unit 141 against each of these drive devices 41. Similarly, a cooling unit 142 is fixedly disposed between the drive devices 41 on the flexible substrates 13c and 13d, and each drive device 41 is cooled by pressing the cooling unit 142 against each of these drive devices 41. Note that such cooling units 141 and 142 can each be configured using various types of cooling mechanisms. As an example, a cooling mechanism is configured by passing a fluid such as ink therethrough.

[0032] [Detailed Configuration Near Flexible Substrates 13a, 13b, 13c, and 13d] Subsequently, with reference to FIGS. 4 to 11 in addition to FIGS. 1 to 3, a detailed configuration example near the aforementioned flexible substrates 13a, 13b, 13c, and 13d in the inkjet head 1 will be described.

[0033] FIG. 4 schematically shows a detailed configuration example of the flexible substrates 13a to 13d (hereinafter collectively referred to as the flexible substrate 13 as appropriate) shown in FIGS. 2 and 3 in a plan view (Z-X plan view). FIG. 5 schematically shows a detailed configuration example in the vicinity of the flexible substrate 13 shown in FIG. 4 in a plan view (Z-X plan view). Further, FIG. 6 schematically shows a configuration example in the vicinity of the flexible substrate 13 shown in FIG. 5 in an exploded perspective view. FIG. 7 schematically shows an arrangement configuration example of a fixing portion 43 (described later) and the like shown in FIG. 6 in a perspective view. FIGS. 8 and 9 each schematically show an arrangement configuration example of the fixing portion 43 and the like shown in FIG. 6 in a plan view (Z-X plan view). Further, FIGS. 10 and 11 each schematically show a configuration example around the driving device 41 on the flexible substrate 13 in a plan view (Z-X plan view). In FIGS. 6 and 7, for convenience, only one driving device 41 out of a plurality of driving devices 41 described later is shown representatively. Further, in FIGS. 6 to 9, for convenience, only one through hole H15 out of a plurality of through holes H11 to H15 described later is shown representatively.

[0034] First, this flexible substrate 13 is a double-sided substrate having a multi-layer structure including a front surface S1 and a back surface S2. Specifically, this flexible substrate 13 has, as wiring layers of such a multi-layer structure (two-layer structure), a first wiring layer on the front surface S1 side and a second wiring layer on the back surface S2 side that face each other along the direction (Y-axis direction) orthogonal to the substrate surface (Z-X plane) (see FIGS. 3 to 9). Note that the wiring layer in the flexible substrate 13 may have a structure of three or more layers including, for example, the above-described first wiring layer and second wiring layer.

[0035] Here, the above-described front surface S1 corresponds to a specific example of the "first surface" in the present disclosure, and the above-described back surface S2 corresponds to a specific example of the "second surface" in the present disclosure.

[0036] As shown in FIGS. 4 to 9, this flexible substrate 13 has the aforementioned one or more drive devices 41 (five drive devices 411 to 415 in this example), a plurality of through holes H11 to H15, a terminal portion 130, and a plurality of electrical contact portions 131. Further, as shown in FIGS. 5 to 7, in the vicinity of the flexible substrate 13 in the inkjet head 1, the aforementioned cooling units 141, 142 (hereinafter collectively referred to as the cooling unit 14 as appropriate), a pressing member 42, and screws F1 to F9 are provided respectively.

[0037] As described above, the drive device 41 is disposed on the substrate of the flexible substrate 13 (on the first wiring layer on the surface S1 side). Specifically, for example, as shown in FIG. 6, a first region A1 as an arrangement region of the drive device 41 extends along the X-axis direction on the surface S1 of the flexible substrate 13. Further, in the examples shown in FIGS. 4, 8 to 11, a plurality of drive devices 41 (five drive devices 411 to 415 in this example) are arranged side by side along the X-axis direction (the longitudinal direction of the flexible substrate 13) on the surface S1 of the flexible substrate 13 (within the above-described first region A1).

[0038] The terminal portion 130 is disposed in an end region on the I / F substrate 12 side of the flexible substrate 13 (see FIGS. 4 to 9) and includes a plurality of terminals for electrically connecting between the flexible substrate 13 and the I / F substrate 12. In other words, this terminal portion 130 is a portion to be inserted into the connectors 120a to 120d on the I / F substrate 12 as another substrate.

[0039] The through-holes H11 to H15 are through-holes provided on the flexible substrate 13, respectively. Specifically, as shown in FIG. 4, the through-holes H11 and H12 are provided near both ends along the Z-axis direction in the vicinity of the end on the terminal portion 130 side along the Z-axis direction. The through-holes H13 and H14 are provided near both ends along the Z-axis direction near the center along the Z-axis direction. Further, as shown in FIGS. 4 and 6, the through-hole H15 is provided in a region (second region A2) along the Z-axis direction within the surface S1 of the flexible substrate 13 with reference to the arrangement position of the drive device 41. The detailed example of the position of this through-hole H15 will be described later.

[0040] As shown in FIGS. 4 and 5, the electrical contact portions 131 are provided around the through-holes H13 and H14, respectively, and are members for ensuring electrical contact between the flexible substrate 13 and the screws F3 and F4 described later. Such electrical contact portions 131 are configured using a conductive member such as a copper foil. As shown in FIG. 4, such electrical contact portions 131 (members for ensuring electrical contact between the flexible substrate 13 and the screws F1, F2, and F5 described later) are not provided around the through-holes H11, H12, and H15, respectively.

[0041] As described above, the cooling unit 14 (141, 142) is disposed on the surface S1 side of the flexible substrate 13 (see FIGS. 5 to 7) and is a member (heat dissipation member) for cooling the drive device 41. Further, as shown in FIG. 5, the flexible substrate 13 is fixed to the cooling unit 14 by inserting screws F1 to F4 described later into the through-holes H11 to H14, respectively. Although details will be described later, as shown in FIGS. 5 and 6, the flexible substrate 13 and the pressing member 42 are fixed to the cooling unit 14 by inserting a screw F5 described later through the pressing member 42 into the through-hole H15. A heat conduction sheet (not shown) is disposed between the cooling unit 14 and the drive device 41, and the cooling unit 14 and the drive device 41 are in thermal contact via this heat conduction sheet.

[0042] As shown in FIG. 5, the pressing member 42 is disposed on the back surface S2 side of the flexible substrate 13 and is a member that presses the flexible substrate 13 against the cooling unit 14. As shown in FIG. 5 for example, the pressing member 42 is fixed by screwing to another metal member (not shown) using screws F6 to F9 described later near both ends along the X-axis direction. Further, as shown in FIGS. 4 and 5, the pressing member 42 is disposed so as to cover the arrangement region (the first region A1 shown in FIG. 6) of the drive device 41. On such a pressing member 42, a through hole H25 is provided in a fixing region 420 (a convex portion along the Z-axis direction) shown in FIG. 5 for example (see FIG. 6). Note that the arrangement position of the fixing region 420 (through hole H25) on the pressing member 42 is not limited to the example shown in FIGS. 5 and 6, and other arrangement positions may be used.

[0043] The screws F1 to F9 are members for fixing various members to each other (fixing by screwing) as described above. In particular, as shown in FIG. 6 for example, a screw F5 for fixing between the flexible substrate 13 and the pressing member 42 is inserted into the through hole H15 on the flexible substrate 13 and the through hole H25 on the pressing member 42 respectively. Further, this screw F5 is also inserted into the cooling unit 14, and the force by which the pressing member 42 presses the drive device 41 (for example, the drive device 413) against the cooling unit 14 in the fixing region 420 is maintained by this screw F5.

[0044] (Fixing portion 43) Here, for example, as shown in FIG. 6, in the inkjet head 1 of the present embodiment, a fixing portion 43 is configured including the above-described through holes H15, H25 and screws F5. As described above, this fixing portion 43 is a mechanism for fixing a part (near the fixing region 420) of the pressing member 42 to the flexible substrate 13. Although details of such a fixing portion 43 will be described later, for example, as shown in FIG. 6, with reference to the arrangement position of the drive device 41 as a reference, in a region (second region A2) along the Z-axis direction orthogonal to the X-axis direction within the surface S1 of the flexible substrate 13, it is arranged.

[0045] In the inkjet head 1 of the present embodiment, the reason for providing such a fixing portion 43 will be described below with reference to a comparative example.

[0046] FIG. 12 schematically shows a configuration example in the vicinity of a drive substrate (flexible substrate 103) in an inkjet head according to a comparative example in a plan view (Z-X plan view). In the vicinity of the flexible substrate 103 of this comparative example, unlike the pressing member 42 (see FIGS. 5 and 6) in the vicinity of the flexible substrate 13 of the present embodiment, the fixing portion 43 is not provided on the pressing member 102. Therefore, in the inkjet head of this comparative example, for example, for the following reasons, there is a risk that the reliability will decrease.

[0047] Specifically, in the flexible substrate 103 of this comparative example, the drive devices 41 (drive devices 411 and 415) on both ends, which are closest to the fixed portions (the fixed portions by screws F6 to F9) near both ends of the pressing member 102, are pressed most strongly against the cooling unit 14. On the other hand, for the drive device 413 located near the center along the X-axis direction, since the center portion of the pressing member 102 along the X-axis direction bends, the force pressing against the cooling unit 14 is often insufficient. In addition, since two drive devices 412 and 414 are arranged at both ends of this drive device 413, in addition to the heat generated during the operation of the drive device 413 itself, it is also affected by the heat generated by the surrounding drive devices 412 and 414, so it is the most thermally disadvantageous location. From these facts, it can be said that measures are required to strongly press against the cooling unit 14 even in the vicinity of the center of the pressing member 102 along the X-axis direction (near the drive device 413).

[0048] Here, referring to FIGS. 7 to 9 in addition to FIGS. 4 to 6, the arrangement configuration example of the above-described fixing portion 43 will be described in detail.

[0049] First, for example, among a plurality of drive devices 41 arranged side by side along the X-axis direction, the fixing portion 43 (through holes H15, etc.) is arranged in a region along the Z-axis direction based on the arrangement position of the drive device 413 closest to the perpendicular bisector L5 of the side (long side) along the X-axis direction within the surface S1 of the flexible substrate 13 (see FIGS. 8 and 9). Particularly in the example of FIG. 9, within the surface S1 of the flexible substrate 13, the fixing portion 43 (through holes H15, etc.) is arranged in a region along the perpendicular bisector L5 of the side (long side) along the X-axis direction of the drive device 41 (drive device 413).

[0050] Further, for example, within the surface S1 of the flexible substrate 13, a fixing portion 43 (such as a through hole H15) is disposed within a region (output terminal side region Aout) that includes the wiring of the drive signal Sd output from the drive device 41 (see FIG. 7). The advantages of disposing the fixing portion 43 (such as the through hole H15) within such an output terminal side region Aout will be described below.

[0051] First, in the example of FIG. 10, an input terminal side region Ain and an output terminal side region Aout, which are located around each of the plurality of drive devices 41 (drive devices 411 to 415), and inter-device regions Ag12, Ag23, Ag34, Ag45, which are located between the drive devices 41, are respectively shown. Note that the inter-device region Ag12 is a region located between the drive devices 411 and 412, and the inter-device region Ag23 is a region located between the drive devices 412 and 413. Similarly, the inter-device region Ag34 is a region located between the drive devices 413 and 414, and the inter-device region Ag45 is a region located between the drive devices 414 and 415.

[0052] Also, in the example of FIG. 11, an input terminal side region Ain and an output terminal side region Aout, which are located around each of the drive devices 412 and 413 shown in FIG. 10, and the above-described inter-device region Ag23 are respectively shown. In FIG. 11, a plurality of input terminals Tin and a plurality of output terminals Tout in each of the drive devices 412 and 413, and a transmission line Lt that is cascade-connected between these drive devices 412 and 413 are also respectively shown. Further, in FIG. 11, various wiring patterns (patterns such as drive signal wiring Wd output from each output terminal Tout, various power supply wirings Wp1, Wp2, and ground wiring Wg) and through holes TH for electrically connecting these wiring patterns to each other are respectively shown.

[0053] In the example of FIG. 11 having such a configuration, examples of the candidate positions for arranging the through hole H15 that constitutes the fixing portion 43 include the following. · First candidate: Input terminal side region Ain · Second candidate: Inter-device region Ag23 · Third candidate: Output terminal side region Aout

[0054] In the input terminal side region Ain, which is the first candidate, various signal lines and components connected to each input terminal Tin in the drive devices 412 and 413 are arranged. On the other hand, in the inter-device region Ag23, which is the second candidate, wiring patterns such as various power supply wirings Wp1 and Wp2 and ground wiring Wg are arranged (see FIG. 11).

[0055] Here, since the through hole H15 penetrates all layers of the flexible substrate 13, as the arrangement position of this through hole H15, regions where components are dense, regions where wiring patterns are complex, and regions where various power supply wirings are arranged are not desirable. Also, since the vicinity of the through hole H15 is the portion where the pressing force from the pressing member 42 is the largest, when such a force is applied near the short side of the rectangular drive device 41, there is a risk of damaging the connection state between the flexible substrate 13 and the terminals of the drive device 41 at that location.

[0056] Considering the above, among the first to third candidates described above, it can be said that it is desirable to arrange the through hole H15 in the output terminal side region Aout, which is the third candidate, that is, near the center of the long side of the arrangement region of the drive device 41.

[0057] Also, in order to arrange the through hole H15 on the flexible substrate 13, a large number of drive signal wirings Wd (see FIG. 11) arranged in the output terminal side region Aout need to be arranged avoiding the through hole H15. As the amount by which these drive signal wirings Wd avoid the through hole H15, it is easier to wire each drive signal wiring Wd if it is as uniform as possible in all the drive signal wirings Wd output from one drive device 41. Therefore, it can be said that the vicinity of the center in the long side direction (X-axis direction) of the drive device 41 is desirable as the arrangement position of the through hole H15.

[0058] Furthermore, as in the examples of FIGS. 10 and 11, when a plurality of drive devices 41 are arranged on the flexible substrate 13, for example, through holes H15 may not be provided in the output terminal side regions Aout of each drive device 41. This is for the following reasons as described above. That is, first, for the drive device 413 located near the center along the X-axis direction, since the vicinity of the center along the X-axis direction in the pressing member 42 bends, the force pressing against the cooling unit 14 becomes weak, and thus the thermal contact with the cooling unit 14 also becomes weak. Also, since two drive devices 412 and 414 are arranged at both ends of this drive device 413, as described above, it is also the place that is thermally most disadvantageous. To solve these problems, it can be said that it is desirable to arrange one through hole H15 in the output terminal side region Aout of this drive device 413 in the vicinity of the center along the X-axis direction (near the drive device 413) in the pressing member 42.

[0059] Here, the above-described X-axis direction corresponds to a specific example of the "first direction" in the present disclosure, and the above-described Z-axis direction corresponds to a specific example of the "second direction" in the present disclosure. Also, the above-described through hole H15 corresponds to a specific example of the "first through hole" in the present disclosure, and the above-described through hole H25 corresponds to a specific example of the "second through hole" in the present disclosure. Further, the above-described screw F5 corresponds to a specific example of the "fixing member" in the present disclosure.

[0060] [Operation, Action, and Effect] (A. Basic Operation of Printer 5) In this printer 5, a recording operation (printing operation) such as an image or characters on a recording medium (recording paper P, etc.) is performed using an ink ejection operation of the ink 9 by the inkjet head 1 as follows. Specifically, in the inkjet head 1 of the present embodiment, an ink ejection operation of the ink 9 using a shear mode is performed as follows.

[0061] First, each drive device 41 on each flexible substrate 13 (13a, 13b, 13c, 13d) applies a drive voltage Vd (drive signal Sd) to the aforementioned drive electrodes (common electrode and active electrode) in the actuator plate 111 in the ejection unit 11. Specifically, each drive device 41 applies the drive voltage Vd to each drive electrode disposed on a pair of drive walls that define the aforementioned ejection channel. As a result, each of these pair of drive walls deforms so as to protrude toward the dummy channel side adjacent to its ejection channel.

[0062] At this time, the drive wall bends and deforms in a V shape with the intermediate position in the depth direction of the drive wall as the center. Then, due to such bending deformation of the drive wall, the ejection channel deforms as if it swells. In this way, the volume of the ejection channel increases due to the bending deformation caused by the piezoelectric thickness-shear effect in the pair of drive walls. And, when the volume of the ejection channel increases, the ink 9 is induced into the ejection channel.

[0063] Next, the ink 9 induced into the ejection channel in this way propagates inside the ejection channel as a pressure wave. And at the timing when this pressure wave reaches the nozzle hole Hn of the nozzle plate 112 (or at a timing in the vicinity thereof), the drive voltage Vd applied to the drive electrode becomes 0 (zero) V. As a result of the drive wall returning from the above-described bent deformation state, the volume of the ejection channel that once increased returns to its original state again.

[0064] In this way, in the process of the volume of the ejection channel returning to its original state, the pressure inside the ejection channel increases and the ink 9 in the ejection channel is pressurized. As a result, droplet-shaped ink 9 is ejected to the outside (toward the recording paper P) through the nozzle hole Hn (see FIG. 1). In this way, the ejection operation (ejection operation) of the ink 9 in the inkjet head 1 is performed, and as a result, a recording operation of an image, characters, etc. on the recording paper P is performed.

[0065] (B. Action and Effect in Inkjet Head 1) Next, the operation and effects of the inkjet head 1 of the present embodiment will be described in detail.

[0066] (B-1. Conventional inkjet head) First, in a drive substrate (a drive substrate on which drive devices are mounted) for driving an inkjet head, generally, the number of wirings related to the input / output of the drive devices is extremely large. For this reason, in order to arrange wirings for heat dissipation of the drive devices, etc., the number of substrate layers is increased and wide heat dissipation wirings (ground wirings and power supply wirings) are arranged in that layer. However, while the number of layers can be easily increased in a rigid substrate, it is difficult to increase the number of layers in a flexible substrate from the cost aspect.

[0067] In recent years, the number of drive nozzles of the inkjet head has increased and the ejection frequency has also become higher. Therefore, in addition to the increase in the mounting density of the drive devices, the heat generation amount of the drive devices has also been increasing. For this reason, the heat dissipation of the drive devices is not sufficient with the heat dissipation wirings arranged on the drive substrate. Therefore, the heat dissipation of the drive devices will be performed by, for example, a cooling member (such as a heat sink) using metal. In order to ensure thermal contact between such a cooling member and the drive device, for example, it is known to secure a heat dissipation path by screwing in the region between a plurality of drive devices.

[0068] When screwing in the region between the drive devices in this way, it is necessary that the region (gap) between the drive devices is larger than the screw. However, considering the circuit mounting density on the substrate, it is desirable that the gap between the drive devices is narrower. And it is necessary to arrange screw holes in that narrow gap region. That is, the requirement to increase the circuit mounting density and the requirement to secure a gap for screw holes are contradictory. This problem becomes more prominent especially when a plurality of rectangular drive devices are arranged side by side along the long side, and there is also a problem that it becomes difficult to achieve thermal contact with the drive devices arranged near the center when a plurality of drive devices are arranged.

[0069] From these points, it can be said that the reliability of a conventional inkjet head may decrease.

[0070] (B-2. Function and Effect) On the other hand, in the inkjet head 1 of the present embodiment, due to the following configuration, for example, the following functions and effects can be obtained.

[0071] That is, first, in this inkjet head 1, on the back surface S2 side of the flexible substrate 13 (the surface side opposite to the surface S1 side where the cooling unit 14 for cooling the drive device 41 is provided), a pressing member 42 for pressing the flexible substrate 13 against the cooling unit 14 is provided. Further, in the inkjet head 1, a fixing portion 43 for fixing a part of the pressing member 42 to the flexible substrate 13 is provided. Thus, in the present embodiment, compared with the above-described comparative example and the like, the pressing force toward the cooling unit 14 with respect to the drive device 41 on the flexible substrate 13 is easily ensured, so that the cooling of the drive device 41 is promoted, and as a result, the operation stability of the drive device 41 is ensured.

[0072] Also, in this inkjet head 1, the arrangement region of the drive device 41 on the flexible substrate 13 extends along the X-axis direction within the surface S1. And with the arrangement position of this drive device 41 as a reference, the fixing portion 43 is arranged in a region along the Z-axis direction orthogonal to the X-axis direction within the surface S1 on the flexible substrate 13. Thus, in the present embodiment, for example, different from the case where the fixing portion 43 is arranged in a region along the X-axis direction with the arrangement position of the drive device 41 as a reference, the following occurs. That is, problems near the end portion in the X-axis direction in the drive device 41 (such as poor connection between the terminals of the drive device 41 and the flexible substrate 13) are avoided.

[0073] From the above, in the present embodiment, for example, compared with the above-described comparative example and the like, it is possible to improve the reliability of the inkjet head 1.

[0074] In addition, in the present embodiment, near the end of the drive device 41, a strong force by the screw F5 is applied to the flexible substrate 13, and the connection between the terminal near the end of the drive device 41 and the flexible substrate 13 is also prevented from being broken. Therefore, it is also possible to improve the reliability in this respect. Further, when a plurality of drive devices 41 are arranged, the above effects can be efficiently obtained with a small number of through holes (one through hole H15), so that the cost can also be reduced. In addition, in the present embodiment, since high-frequency ejection is also possible, the productivity of the printer 5 is improved, and the return line of the drive signal Sd output from the drive device 41 is also easily secured. Therefore, it is possible to obtain the above effects while ensuring the reliability. Also, in the present embodiment, by configuring the flexible substrate 13 in such a manner, appropriate through holes can be arranged according to, for example, the size and number of the drive devices 41. Therefore, it is possible to improve the reliability and reduce the cost while ensuring the design freedom of the inkjet head 1.

[0075] Furthermore, in the present embodiment, in the arrangement region of the drive device 41, since a plurality of drive devices 41 are arranged side by side along the X-axis direction, the following occurs. That is, since the drive devices 41 are arranged along the longitudinal direction, the path of the wiring pattern on the flexible substrate 13 becomes short and simple. Therefore, it is possible to reduce the size of the flexible substrate 13.

[0076] In addition, in the present embodiment, among the plurality of drive devices 41 arranged side by side along the X-axis direction, when the fixing portion 43 is arranged in the region along the Z-axis direction based on the arrangement position of the drive device 413 closest to the perpendicular bisector L5 along the X-axis direction in the surface S1 of the flexible substrate 13, the following occurs. That is, by arranging such a fixing portion 43 (through hole H15), the through hole H15 can be arranged only near the center of the flexible substrate 13 where the heat distribution is largely biased, and the number of necessary members and through holes can be reduced.

[0077] Also, in the present embodiment, since the number of the plurality of drive devices 41 on the flexible substrate 13 is odd (five), the following occurs. That is, when the number of drive devices 41 is odd, while the number of through holes (through hole H15) added with the provision of the fixing portion 43 is one, the above-described effects can be obtained. As a result, it is possible to improve the reliability and reduce the cost while ensuring the design freedom of the inkjet head 1.

[0078] Furthermore, in the present embodiment, when the fixing portion 43 is arranged in a region along the perpendicular bisector L5 with respect to the side along the X-axis direction in the drive device 41 within the surface S1 of the flexible substrate 13, the following occurs. That is, by arranging the fixing portion 43 (through hole H15) in this way, since the vicinity of the center of the drive device 41 can be cooled by the cooling unit 14, the bias of the heat distribution within the drive device 41 can be reduced. Also, it is possible to prevent the vicinity of the end portion of the drive device 41 from cracking due to the pressing force from the fixing portion 43. As a result, it is possible to improve the reliability of the flexible substrate 13 itself.

[0079] In addition, in the present embodiment, when the fixing portion 43 is arranged in a region (output terminal side region Aout) including the wiring of the drive signal Sd output from the drive device 41 within the surface S1 of the flexible substrate 13, the following occurs. That is, by arranging the fixing portion 43 (through hole H15) in a region avoiding the region where components around the drive device 41 and lines for the drive power supply are arranged, the wiring arrangement for avoiding the through hole H15 becomes easy. Thereby, while ensuring the stable operation of the drive device 41, since it is possible to create the flexible substrate 13 in which the through hole H15 is arranged, it is possible to further improve the reliability of the inkjet head 1.

[0080] In addition, in the present embodiment, a through hole H15 provided on the flexible substrate 13, a through hole H25 provided on the pressing member 42, and a fixing member (screw F5) inserted into these through holes H15 and H25 to fix between the flexible substrate 13 and the pressing member 42 are included, and the fixing portion 43 is configured. Therefore, the following is achieved. That is, for example, even when the drive device 41 is away from the end of the flexible substrate 13, the arrangement area of the drive device 41 can be surely pressed against the cooling unit 14, and the pressing member 42 can be surely fixed.

[0081] Furthermore, in the present embodiment, since the electrical contact portion 131 between the flexible substrate 13 and the screw F5 is not provided around the through hole H15 that constitutes the fixing portion 43, the following is achieved. That is, on the flexible substrate 13, the arrangement area of components and wirings that avoid the through hole H15 can be reduced, and the arrangement of power supply lines and components that contribute to the stable operation of the inkjet head 1 becomes possible.

[0082] In addition, in the present embodiment, since the drive substrate for driving the inkjet head 1 is configured by the flexible substrate 13, the following is achieved. That is, the design freedom and assemblability of the inkjet head 1 can be improved, and the miniaturization and yield improvement of the inkjet head 1 can be achieved.

[0083] <2. Modification Example> Subsequently, modification examples (modification examples 1 and 2) of the above embodiment will be described. Note that the same components as those in the embodiment are denoted by the same reference numerals, and the description will be omitted as appropriate.

[0084] FIG. 13 schematically shows a configuration example in the vicinity of a flexible substrate (flexible substrate 13A) according to Modification Example 1 in a plan view (Z-X plan view). FIG. 14 schematically shows a configuration example in the vicinity of a flexible substrate (flexible substrate 13B) according to Modification Example 2 in a plan view (Z-X plan view).

[0085] The flexible substrates 13A and 13B of these first and second modified examples are each obtained by varying (changing) the number of drive devices 41 in the flexible substrate 13 of the embodiment, and the other configurations are basically the same. Specifically, in the flexible substrate 13A of the first modified example shown in FIG. 13, three (an odd number) of drive devices 411 to 413 are arranged side by side along the X-axis direction. On the other hand, in the flexible substrate 13B of the second modified example shown in FIG. 14, four (an even number) of drive devices 411 to 414 are arranged side by side along the X-axis direction.

[0086] Here, in the flexible substrate 13A of the first modified example, in the same manner as in the case of the flexible substrate 13 of the embodiment, the through holes H15 constituting the fixing portion 43 are arranged in the following regions. That is, the through holes H15 constituting the fixing portion 43 are arranged in the region along the Z-axis direction (the output terminal side region Aout described above) based on the arrangement position of the drive device 412 closest to the perpendicular bisector of the side along the X-axis direction.

[0087] Here, in the flexible substrate 13A of the first modified example, in the same manner as in the case of the flexible substrate 13 of the embodiment, the through holes H15 constituting the fixing portion 43 are arranged as follows. That is, one through hole H15 constituting the fixing portion 43 is arranged in the region along the Z-axis direction (the output terminal side region Aout described above) based on the arrangement position of one drive device 412 closest to the perpendicular bisector of the side along the X-axis direction.

[0088] On the other hand, in the flexible substrate 13B of Modification 2, the through-holes H15 that constitute the fixing portion 43 are arranged as follows, which is somewhat different from the case of the flexible substrate 13 in the embodiment. That is, in the region along the Z-axis direction (the output terminal side region Aout described above) based on the arrangement positions of the two drive devices 412 and 413 that are closest to the perpendicular bisector of the side along the X-axis direction, the two through-holes H151 and H152 that constitute the fixing portion 43 are respectively arranged. Note that, similar to the periphery of the through-hole H15, the electrical contact portion 131 described above is not provided around these through-holes H151 and H152. Also, both of the through-holes H151 and 152 may be arranged, or only one of the through-holes H151 and H152 may be arranged.

[0089] In this way, the configuration and arrangement region of the fixing portion 43 are set according to whether the number of drive devices 41 is odd or even.

[0090] Note that the flexible substrates 13A and 13B respectively correspond to a specific example of the "drive substrate" in the present disclosure. Also, the through-holes H151 and H152 respectively correspond to a specific example of the "first through-hole" in the present disclosure.

[0091] Also in Modifications 1 and 2 having such a configuration, basically the same operations as in the embodiment are performed, and the same effects are obtained.

[0092] <3. Other Modifications> As described above, the present disclosure has been described by way of the embodiment and the modifications. However, the present disclosure is not limited to these embodiments and the like, and various modifications are possible.

[0093] For example, in the above embodiment and the like, the configuration examples (shape, arrangement, number, etc.) of each member in the printer and the inkjet head have been specifically described. However, it is not limited to those described in the above embodiment and the like, and other shapes, arrangements, numbers, etc. may be used.

[0094] Specifically, for example, in the above embodiments and the like, configuration examples (shape, arrangement, number, etc.) of a flexible substrate, a driving device, a fixing portion, and various wiring patterns have been specifically cited and described. However, these configuration examples are not limited to those described in the above embodiments and the like. For example, in the above embodiments and the like, an example in which a plurality of driving substrates are provided in the inkjet head has been described. However, this example is not limited thereto. For example, only one driving substrate may be provided in the inkjet head. Further, in the above embodiments and the like, an example in which a plurality of driving devices are provided on the driving substrate has been described. However, this example is not limited thereto. For example, only one driving device may be provided on the driving substrate. Furthermore, in the above embodiments and the like, an example in which the driving substrate is a flexible substrate has been described. However, this example is not limited thereto. For example, the driving substrate may be a non-flexible substrate (rigid substrate). In addition, in the above embodiments and the like, the shape of the driving device is rectangular, but this example is not limited thereto. For example, it may be square. Also, in the above embodiments and the like, as a specific example of the "fixing member" in the present disclosure, a screw has been cited and described. However, this example is not limited thereto. Other members (for example, pins of a pin badge, dowels, etc.) may be used to constitute the "fixing member".

[0095] Moreover, as the structure of the inkjet head, various types can be applied. That is, for example, it may be a so-called side-shoot type inkjet head that discharges ink 9 from the central portion in the extending direction of each discharge channel in the actuator plate 111. Alternatively, for example, it may be a so-called edge-shoot type inkjet head that discharges ink 9 along the extending direction of each discharge channel. Furthermore, as the printer method, it is not limited to the method described in the above embodiments and the like. For example, various methods such as the MEMS (Micro Electro Mechanical Systems) method can be applied.

[0096] Furthermore, for example, the present disclosure can be applied to either a circulating inkjet head that circulates and uses ink 9 between an ink tank and an inkjet head, or a non-circulating inkjet head that uses ink 9 without circulation.

[0097] Also, the series of processes described in the above embodiments etc. may be performed by hardware (circuit), or may be performed by software (program). When performed by software, the software is composed of a group of programs for causing a computer to execute each function. Each program may be, for example, pre-installed in the above computer and used, or may be installed from a network or a recording medium into the above computer and used.

[0098] Furthermore, in the above embodiments etc., as a specific example of the "liquid jet recording apparatus" in the present disclosure, a printer 5 (inkjet printer) was given and described, but this is not limited to this example, and the present disclosure can also be applied to other apparatuses other than inkjet printers. In other words, the "liquid jet head" (inkjet head) of the present disclosure may be applied to other apparatuses other than inkjet printers. Specifically, for example, the "liquid jet head" of the present disclosure may be applied to apparatuses such as facsimiles and on-demand printers.

[0099] In addition, the various examples described so far may be applied in any combination.

[0100] Note that the effects described in this specification are merely examples and are not limiting, and there may be other effects.

[0101] Also, the present disclosure can also take the following configuration. (1) An ejection unit having a plurality of nozzles for ejecting a liquid, One or more drive devices that output a drive signal for ejecting the liquid from the nozzle to the ejection unit are disposed on a drive substrate disposed on a first surface, and a heat dissipation member that is disposed on the first surface side of the drive substrate and cools the drive device, and a pressing member that is disposed on a second surface side of the drive substrate facing the first surface and presses the drive substrate against the heat dissipation member, and a fixing portion that fixes a part of the pressing member to the drive substrate are provided, the arrangement region of the drive devices extends along a first direction in the first surface, the fixing portion is disposed in a region along a second direction orthogonal to the first direction in the first surface, with reference to the arrangement position of the drive devices. Liquid ejection head. (2) In the arrangement region of the drive devices, a plurality of the drive devices are arranged side by side along the first direction The liquid ejection head according to (1) above. (3) Among the plurality of drive devices arranged side by side along the first direction, in a region along the second direction with reference to the arrangement positions of one or more of the drive devices closest to the perpendicular bisector of the side along the first direction in the first surface of the drive substrate, the fixing portion is disposed. The liquid ejection head according to (2) above. (4) The number of the plurality of drive devices is odd The liquid ejection head according to (3) above. (5) In the first surface, the fixing portion is disposed in a region along the perpendicular bisector of the side along the first direction in the drive device. The liquid ejection head according to any one of (1) to (4) above. (6) The fixing portion is disposed within a region including the wiring of the drive signal output from the drive device within the first surface. The liquid ejection head according to (5) above. (7) The fixing portion a first through hole provided on the drive substrate, a second through hole provided on the pressing member, and a fixing member that is inserted into the first through hole and the second through hole respectively and fixes between the drive substrate and the pressing member and is configured to include The liquid ejection head according to any one of (1) to (6) above. (8) Around the first through hole, an electrical contact portion between the drive substrate and the fixing member is not provided. The liquid ejection head according to (7) above. (9) The drive substrate is a flexible substrate. The liquid ejection head according to any one of (1) to (8) above. (10) A liquid ejection recording apparatus including the liquid ejection head according to any one of (1) to (9) above Liquid ejection recording apparatus.

Explanation of Signs

[0102] 1... Inkjet head, 10... Connector, 11... Injection part, 111... Actuator plate, 112... Nozzle plate, 12... I / F substrate, 120a, 120b, 120c, 120d... Connectors, 121... Circuit arrangement area, 13, 13a, 13b, 13c, 13d, 13A, 13B... Flexible substrates, 130... Connection electrodes, 131... Electrical contact parts, 14, 141, 142... Cooling units, 2... Printing control unit, 3... Ink tank, 30... Ink supply pipe, 41, 411~415... Driving devices, 42... Pressing member, 420... Fixed area, 43... Fixing part, 433... Crimping electrode, 5... Printer, 9... Ink, P... Recording paper, Hn... Nozzle hole, Sc... Printing control signal, Sd... Driving signal, Vd... Driving voltage, S1... Surface, S2... Back surface, A1... First area, A2... Second area, Ain... Input terminal side area, Aout... Output terminal side area, Ag12, Ag23, Ag34, Ag45... Area between devices, H11~H15, H151, H152, H25... Through holes, F1~F9... Screws, Wd... Driving signal wiring, Wp1, Wp2... Power supply wiring, Wg... Ground wiring, Lt... Transmission line, Tin... Input terminal, Tout... Output terminal, TH... Through hole.

Claims

1. An injection unit having a plurality of nozzles for injecting a liquid, a drive substrate on which one or a plurality of drive devices for outputting a drive signal for injecting the liquid from the nozzles to the injection unit are arranged on a first surface, a heat radiating member arranged on the first surface side of the drive substrate for cooling the drive device, a pressing member arranged on a second surface side of the drive substrate facing the first surface for pressing the drive substrate against the heat radiating member, and a fixing portion for fixing a part of the pressing member to the drive substrate and comprising, wherein an arrangement region of the drive devices extends along a first direction within the first surface, the fixing portion is arranged in a region along a second direction orthogonal to the first direction within the first surface with reference to an arrangement position of the drive devices, a liquid injection head.

2. Within the arrangement region of the drive devices, a plurality of the drive devices are arranged side by side along the first direction The liquid injection head according to Claim 1.

3. Among a plurality of the drive devices arranged side by side along the first direction, in a region along the second direction with reference to an arrangement position of one or a plurality of the drive devices closest to a perpendicular bisector of a side along the first direction within the first surface of the drive substrate, the fixing portion is arranged The liquid injection head according to Claim 2.

4. The number of the plurality of drive devices is odd The liquid injection head according to Claim 3.

5. Within the first surface, the fixing portion is arranged in a region along a perpendicular bisector of a side along the first direction of the drive device The liquid injection head according to any one of Claims 1 to 4.

6. The fixing portion is arranged within a region including wiring of the drive signal output from the drive device within the first surface The liquid injection head according to Claim 5.

7. The fixing portion a first through hole provided on the drive substrate, a second through hole provided on the pressing member, and a fixing member inserted into the first through hole and the second through hole respectively for fixing between the drive substrate and the pressing member and is configured to include The liquid injection head according to any one of Claims 1 to 4.

8. Around the first through hole, an electrical contact portion between the drive substrate and the fixing member is not provided The liquid ejection head according to claim 7.

9. The drive substrate is a flexible substrate The liquid ejection head according to any one of claims 1 to 4.

10. Comprising the liquid ejection head according to any one of claims 1 to 4 Liquid ejection recording apparatus.

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