Liquid ejection head and liquid ejection recording apparatus

Abstract

To reduce the number of flexible substrates to be installed in a liquid jet head.SOLUTION: An inkjet head 5 includes a head chip 30 for jetting ink, a driving circuit substrate 60 for outputting a driving signal of the head chip 30, and a flexible substrate 70 for electrically connecting the driving circuit substrate 60 and the head chip 30, wherein the head chip 30 has a first actuator array 33 and a second actuator array 34 driven on the basis of the driving signal, and the flexible substrate 70 has a first connection part 71 electrically connected to the driving circuit substrate 60, a second connection part 72 electrically connected to the first actuator array 33, and a third connection part 73 electrically connected to the second actuator array 34.SELECTED DRAWING: Figure 6

Description

Technical Field

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

Background Art

[0002] Patent Document 1 below discloses a liquid ejection head including: a head unit (ejection unit) having first and second channel rows (actuator rows); a driver IC (drive circuit) that generates a drive signal; a first terminal row electrically connected to the driver IC; and a second terminal row electrically connected to the driver IC, the first terminal row being electrically connected to the head unit to supply a drive signal for driving the first channel row to the head unit, a first flexible substrate; a third terminal row; and a fourth terminal row electrically connected to the third terminal row, the third terminal row being electrically connected to the second terminal row of the first flexible substrate, the fourth terminal row being electrically connected to the head unit to supply a drive signal for driving the second channel row to the head unit, a second flexible substrate.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the conventional liquid ejection head, the same number of flexible substrates as the number of actuator rows are required to electrically connect the drive circuit board having a drive circuit and each row of actuator rows. For this reason, the number of flexible substrates installed in the liquid ejection head is large, which has hindered miniaturization and cost reduction.

[0005] The present disclosure has been made in view of the above problems, and an object thereof is to reduce the number of flexible substrates installed in a liquid ejection head.

Means for Solving the Problems

[0006] (1) A liquid ejection head according to an aspect of the present disclosure includes an ejection unit that ejects a liquid, a drive circuit board that outputs a drive signal for the ejection unit, and a flexible board that electrically connects the drive circuit board and the ejection unit. The ejection unit has a first actuator row and a second actuator row that are driven based on the drive signal. The flexible board has a first connection portion electrically connected to the drive circuit board, a second connection portion electrically connected to the first actuator row, and a third connection portion electrically connected to the second actuator row.

[0007] According to the liquid ejection head according to this aspect, since one flexible board has two outputs (the second connection portion and the third connection portion) for one input (the first connection portion), two actuator rows can be driven by one flexible board. Therefore, the number of flexible boards installed in the liquid ejection head can be reduced.

[0008] (2) In the liquid ejection head according to the aspect of (1), the drive circuit board has a drive terminal row electrically connected to the first connection portion, and the drive terminal row may have a terminal group composed of a plurality of terminals arranged at a predetermined pitch.

[0009] In this case, since one flexible board has two outputs for one input, there is no need to provide a space between the connection row with the first actuator row and the connection row with the second actuator row in the drive terminal row of the drive circuit board. Therefore, the drive terminal row can be shortened, the drive circuit board can be made smaller, and the liquid ejection head can be miniaturized.

[0010] (3) In the liquid ejection head according to the aspect of (1) or (2), in the flexible substrate, the first distance between the first connection portion and the second connection portion may be longer than the second distance between the first connection portion and the third connection portion.

[0011] In this case, since the first distance between the first connection portion and the second connection portion is longer than the second distance between the first connection portion and the third connection portion, by bending the second connection portion side toward the third connection portion side, the second connection portion and the third connection portion can be connected to the ejection portion at substantially the same position.

[0012] (4) In the liquid ejection head according to the aspect of (3), a bent portion bent toward the third connection portion side may be formed between the first connection portion and the second connection portion on the flexible substrate.

[0013] In this case, by bending the second connection portion toward the third connection portion side starting from the bent portion, the ejection portion can be sandwiched between the second connection portion and the third connection portion, and the second connection portion and the third connection portion can be connected to the ejection portion at substantially the same position.

[0014] (5) In the liquid ejection head according to the aspect of (4), the bent portion may have relatively low rigidity when bent compared to the surrounding area.

[0015] In this case, since the bent portion is relatively easier to bend compared to the surrounding area, the bending position of the flexible substrate can be adjusted to the designed position.

[0016] (6) In the liquid ejection head according to the aspect of (5), a sheet-like conductive pattern may be formed in the surrounding area.

[0017] In this case, by forming a sheet-like conductive pattern in the area around the bent portion, the area around the bent portion can be made difficult to bend, and the flexible substrate can be made relatively easier to bend at the bent portion.

[0018] (7) In the liquid ejection head according to the aspect of (4), the bent portion may be more likely to maintain the shape after being bent relative to other regions of the flexible substrate.

[0019] In this case, since the bent portion is more likely to maintain the shape after being bent relative to other regions of the flexible substrate, the bent state of the flexible substrate can be maintained, and the elastic reaction force of the base material of the flexible substrate applied to the contact of the second connection portion can be reduced.

[0020] (8) In the liquid ejection head according to the aspect of (7), a sheet-like conductive pattern may be formed on the bent portion.

[0021] In this case, by forming a sheet-like conductive pattern in the range of the bent portion, the bent state of the flexible substrate can be maintained, and the elastic reaction force of the base material of the flexible substrate applied to the contact of the second connection portion can be reduced.

[0022] (9) In the liquid ejection head according to the aspect of (8), a gap extending along the bending line of the bent portion may be formed in the conductive pattern.

[0023] In this case, due to the gap in the conductive pattern, it becomes easier to bend the bent portion along the bending line. Therefore, the bending position of the flexible substrate can be adjusted to the designed position, and as a result, the workability during assembly can be improved.

[0024] (10) In the liquid ejection head according to any one of the aspects of (1) to (9), in the flexible substrate, the second connection portion and the third connection portion may be arranged with the first connection portion interposed therebetween.

[0025] In this case, when the flexible substrate is opened, the second connection portion and the third connection portion are arranged in the same plane, so that it becomes easier to manufacture the flexible substrate.

[0026] (11) In the liquid ejection head according to any one of aspects (1) to (10), on the flexible substrate, the second connection portion and the third connection portion may be arranged on a surface different from the first connection portion.

[0027] In this case, when the flexible substrate is bent, since each of the second connection portion and the third connection portion is arranged on the inner peripheral side sandwiching the ejection portion, the connection to the ejection portion becomes easy. Further, since the first connection portion is arranged on a surface different from the second connection portion and the third connection portion, it is arranged on the outer peripheral side when the flexible substrate is bent, and the connection to the drive circuit board becomes easy.

[0028] (12) In the liquid ejection head according to any one of aspects (1) to (11), the first connection portion may have a first connection terminal row arranged in one direction.

[0029] In this case, since the first connection terminal row of the first connection portion is arranged in one direction, the connection such as pressure bonding to the drive circuit board becomes easy.

[0030] (13) In the liquid ejection head according to the aspect of (12), the first connection terminal row has a first portion electrically connected to the second connection portion and a second portion electrically connected to the third connection portion, the second connection portion has a second connection terminal row formed longer than the first portion of the first connection terminal row in the one direction, and the third connection portion may have a third connection terminal row formed longer than the second portion of the first connection terminal row in the one direction.

[0031] In this case, in the second connection portion and the third connection portion, the connection terminals can be connected to the ejection portion with a wider interval than in the first connection portion.

[0032] (14) In the liquid ejection head according to the aspect of (13), the second connection terminal row may extend to the second portion side of the first connection terminal row in the one direction, and the third connection terminal row may extend to the first portion side of the first connection terminal row in the one direction.

[0033] In this case, even when the interval between the connection terminals is widened in the second connection portion and the third connection portion compared to the first connection portion, the formation ranges of the second connection terminal row and the third connection terminal row overlap in one direction so that they overlap when the flexible substrate is bent, thereby making it unnecessary to widen the width of the flexible substrate and enabling miniaturization of the liquid ejection head.

[0034] (15) The liquid ejection recording apparatus according to one aspect of the present disclosure includes the liquid ejection head according to any one of aspects (1) to (14).

[0035] According to the liquid ejection recording apparatus according to this aspect, a small and low-cost product can be provided.

Effect of the Invention

[0036] According to one aspect of the present disclosure described above, the number of flexible substrates installed in the liquid ejection head can be reduced.

Brief Description of the Drawings

[0037]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Mode for Carrying Out the Invention

[0038] Hereinafter, embodiments according to the present disclosure will be described with reference to the drawings.

[0039] In the embodiments and modifications described below, corresponding configurations may be denoted by the same reference numerals and the description thereof may be omitted. Further, in the following description, expressions indicating relative or absolute arrangements such as "parallel", "orthogonal", "center", "coaxial", etc. represent not only strictly such arrangements, but also states in which they are relatively displaced with tolerances and angles or distances that provide the same function.

[0040] In the following embodiments, an inkjet printer (hereinafter simply referred to as a printer) that performs recording on a recording medium using ink (liquid) will be described as an example. In the drawings used in the following description, the scale of each member is appropriately changed in order to make each member recognizable in size.

[0041] (First Embodiment) [Printer 1] FIG. 1 is a schematic configuration diagram of a printer 1 according to the first embodiment. As shown in FIG. 1, the printer 1 (liquid ejection recording apparatus) of the present embodiment includes a pair of conveyance mechanisms 2 and 3, an ink supply mechanism 4, an inkjet head 5 (liquid ejection head), and a scanning mechanism 6.

[0042] In the following description, the orthogonal coordinate system of X, Y, and Z will be used as necessary. The X direction is the conveyance direction (sub-scanning direction) of the recording medium P (for example, paper or the like). The Y direction is the scanning direction (main scanning direction) of the scanning mechanism 6. The Z direction is the height direction (gravity direction) orthogonal to the X direction and the Y direction.

[0043] Also, in the following description, among the X direction, Y direction, and Z direction, the side of the arrow in the figure is defined as the plus (+) side, and the side opposite to the arrow is defined as the minus (-) side. In the present embodiment, 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.

[0044] The conveyance mechanisms 2 and 3 convey the recording medium P to the +X side. The conveyance mechanisms 2 and 3 each include, for example, a pair of rollers 11 and 12 extending in the Y direction. The ink supply mechanism 4 includes an ink tank 15 in which ink is stored, and an ink pipe 16 connecting the ink tank 15 and the inkjet head 5.

[0045] The ink tank 15 stores, for example, four colors of ink: yellow, magenta, cyan, and black separately. A plurality of inkjet heads 5 are provided and are configured to be able to eject the four colors of ink: yellow, magenta, cyan, and black, respectively, according to the connected ink tank 15. Note that the ink stored in the ink tank 15 can also be an aqueous ink (conductive ink) using water as a solvent.

[0046] The scanning mechanism 6 reciprocally scans the inkjet head 5 in the Y direction. The scanning mechanism 6 includes a guide rail 22 and a carriage 23 supported by the guide rail 22 so as to be movable in the Y direction. The inkjet head 5 reciprocates in the Y direction in a state of being mounted on the carriage 23 during the printing operation on the recording medium P.

[0047] <Inkjet head> FIG. 2 is a perspective view of the inkjet head 5 according to the first embodiment. FIG. 3 is an exploded perspective view of the inkjet head 5 according to the first embodiment. Note that each inkjet head 5 has the same configuration except for the color of the supplied ink. Therefore, in the following description, one inkjet head 5 will be described as an example, and the description of the other inkjet heads 5 will be omitted. As shown in FIGS. 2 and 3, the inkjet head 5 includes a head chip 30 (injection unit) in which first nozzle holes 31 and second nozzle holes 32 for ejecting ink are formed in two rows.

[0048] The head chip 30 mainly includes a first actuator row 33 and a second actuator row 34, a nozzle plate 35, a nozzle cap 36, and a nozzle guard 37.

[0049] The first actuator row 33 is a so-called edge shoot type head chip that ejects ink from the tip portion in the channel extending direction (Z direction) in the discharge channel 43. The first actuator row 33 is configured by laminating a first actuator plate 41 and a first cover plate 42 in the Y direction.

[0050] The first actuator plate 41 is a so-called monopole substrate in which the polarization direction is set in one direction along the thickness direction (Y direction). The first actuator plate 41 is preferably formed of a ceramic substrate made of, for example, PZT (lead zirconate titanate). Further, the first actuator plate 41 may be formed by laminating two piezoelectric substrates having different polarization directions in the Y direction (so-called chevron type).

[0051] On the surface of the first actuator plate 41 (the surface facing the first cover plate 42), a discharge channel 43 and a non-discharge channel 44 are arranged alternately at intervals in the X direction. The discharge channel 43 and the non-discharge channel 44 are each formed linearly along the Z direction and open at least at the lower end surface of the first actuator plate 41. Each of the discharge channel 43 and the non-discharge channel 44 is partitioned in the X direction by a drive wall 45 formed of the first actuator plate 41.

[0052] The first cover plate 42 is formed in a rectangular shape in a plan view seen from the Y direction. The first cover plate 42 is joined to the surface of the first actuator plate 41 with the upper end portion of the first actuator plate 41 exposed. The first cover plate 42 has a common ink chamber 46 and a plurality of slits 47.

[0053] The common ink chamber 46 is formed at a position equivalent to the upper end portion of the discharge channel 43 in the Z direction. The common ink chamber 46 is recessed toward the back surface of the first cover plate 42 (the surface facing the first actuator plate 41) and extends in the X direction. Ink flows into the common ink chamber 46 through the above-described ink supply mechanism 4 (see FIG. 1).

[0054] The slit 47 is formed at a position in the common ink chamber 46 that faces the discharge channel 43 in the Y direction. This slit 47 communicates the inside of the common ink chamber 46 and the inside of each discharge channel 43 separately. On the other hand, the non-discharge channel 44 does not communicate with the inside of the common ink chamber 46.

[0055] The second actuator row 34 is configured by laminating a second actuator plate 51 and a second cover plate 52 in the Y direction. The first actuator row 33 and the second actuator row 34 are integrated by joining the back surfaces of the first actuator plate 41 and the second actuator plate 51 together. In the following description, components of the second actuator row 34 that are the same as those of the first actuator row 33 may be denoted by the same reference numerals as the first actuator row 33, and the description thereof may be omitted.

[0056] The discharge channels 43 and non-discharge channels 44 of the second actuator row 34 are arranged with a half-pitch shift relative to the arrangement pitch of the discharge channels 43 and non-discharge channels 44 of the first actuator row 33. That is, the discharge channels 43 and non-discharge channels 44 are arranged in a staggered pattern when viewed from the Z direction. In this case, the discharge channel 43 of the first actuator row 33 and the non-discharge channel 44 of the second actuator row 34 face each other in the Y direction, and the non-discharge channel 44 of the first actuator row 33 and the discharge channel 43 of the second actuator row 34 face each other in the Y direction. Note that, between the first actuator row 33 and the second actuator row 34, the arrangement pitch of the discharge channels 43 and non-discharge channels 44 can be changed as appropriate. That is, the discharge channels 43 and non-discharge channels 44 may be formed at the same position or different positions in the X direction.

[0057] The nozzle cap 36 is a plate-like member having a rectangular outer shape in plan view when viewed from the Z direction. The nozzle cap 36 is formed with a fitting hole 55 that penetrates the nozzle cap 36 in the Z direction. The first actuator row 33 and the second actuator row 34 are collectively fitted into the fitting hole 55. In the example of FIG. 3, the first actuator row 33 and the second actuator row 34 are fitted into the fitting hole 55 such that their lower end surfaces are flush with the lower end surface of the nozzle cap 36.

[0058] As shown in FIG. 3, the nozzle plate 35 is fixed to the lower end surfaces of the first actuator row 33 and the second actuator row 34 and the lower end surface of the nozzle cap 36 by, for example, adhesion or the like. The nozzle plate 35 has a single-layer structure or a laminated structure made of a resin material (such as polyimide), a metal material (such as SUS), glass, or the like.

[0059] A plurality of nozzle rows (a first nozzle row 56 and a second nozzle row 57) extending in the X direction are formed in the nozzle plate 35. The first nozzle row 56 and the second nozzle row 57 extend in parallel with each other at intervals in the X direction.

[0060] The first nozzle row 56 has first nozzle holes 31 that penetrate the nozzle plate 35 in the Z direction. The first nozzle holes 31 are respectively formed at positions in the nozzle plate 35 that face the discharge channels 43 of the first actuator row 33 in the Z direction. That is, the first nozzle holes 31 are linearly arranged at intervals in the X direction.

[0061] The second nozzle row 57 has second nozzle holes 32 that penetrate the nozzle plate 35 in the Z direction. The second nozzle holes 32 are respectively formed at positions in the nozzle plate 35 that face the discharge channels 43 of the second actuator row 34 in the Z direction. That is, the second nozzle holes 32 are linearly arranged at intervals in the X direction. Note that the first nozzle holes 31 and the second nozzle holes 32 are formed in a tapered shape that gradually tapers from top to bottom.

[0062] As shown in FIGS. 2 and 3, the nozzle guard 37 is formed by subjecting a plate material such as SUS to press working. The nozzle guard 37 is formed in a box shape that opens upward. The nozzle guard 37 covers the nozzle plate 35 from below in a state of being externally fitted to the nozzle cap 36.

[0063] Of the nozzle guard 37, in portions facing the first nozzle row 56 and the second nozzle row 57 in the Z direction, exposed holes (first exposed hole 58 and second exposed hole 59) penetrating the nozzle guard 37 in the Z direction are respectively formed. The first exposed hole 58 and the second exposed hole 59 are formed in a slit shape extending in the X direction. The first nozzle row 56 and the second nozzle row 57 are exposed to the outside through the corresponding first exposed hole 58 and second exposed hole 59.

[0064] The discharge channel 43 is sandwiched from both sides in the X direction by a pair of drive walls 45. The discharge channel 43 is filled with ink. On the other hand, the non-discharge channel 44 is not filled with ink. An electrode portion (not shown) is formed on the drive wall 45 by vapor deposition or the like. The drive signal is input to the electrode portion from the drive circuit board 60 shown in FIGS. 5 and 6 described later via the flexible board 70, and the drive wall 45 is deformed by the piezoelectric slip effect.

[0065] The electrode portion is bent and deformed in a V shape so as to bring a pair of drive walls 45 sandwiching the discharge channel 43 in the X direction closer or farther apart. The electrode portion includes an individual electrode (not shown) provided individually for each discharge channel 43 and a common electrode (not shown) commonly connected to each of the discharge channels 43. The terminal of the common electrode and the terminal of the individual electrode extend to the upper end portions of the first actuator plate 41 and the second actuator plate 51, respectively.

[0066] The terminal of the common electrode and the terminal of the individual electrode are electrically connected to the drive circuit board 60 via the flexible board 70 described later, which is connected to the upper end portions of the first actuator plate 41 and the second actuator plate 51, respectively. When a drive signal is input (a + potential is applied) from the control unit to the individual electrode with the common electrode as the reference potential GND, the pair of drive walls 45 are bent and deformed in a V shape so as to separate from each other. That is, the pair of drive walls 45 are deformed so that the volume of the discharge channel 43 expands.

[0067] After increasing the volume of each ejection channel 43, the voltage applied between the common electrode and the individual electrodes is set to zero. Then, the pair of drive walls 45 is restored, and the volume of the ejection channel 43 that has once increased returns to its original volume. As a result, the pressure inside the ejection channel 43 increases, and the ink is pressurized. Consequently, the ink is ejected in droplets through the first nozzle hole 31 and the second nozzle hole 32. By landing the ejected ink on the recording medium P shown in FIG. 1, characters, images, etc. can be recorded on the recording medium P. Note that a configuration may be adopted in which a + potential is applied from the control unit to the individual electrodes to increase the volume of each ejection channel 43, then the individual electrodes are connected to the reference potential GND to return the volume of each ejection channel 43, and then a - potential is applied to the individual electrodes to reduce the volume of each ejection channel 43 and push out the ink.

[0068] <Drive circuit board> FIG. 4 is a perspective view of a drive circuit board 60 according to the first embodiment. FIG. 5 is a schematic configuration diagram of the drive circuit board 60 according to the first embodiment. FIG. 6 is a cross-sectional view taken along the arrow VI-VI shown in FIG. 5. As shown in FIGS. 4 and 5, the drive circuit board 60 includes a main body portion 61 having a plurality of drive circuits 63 that output the drive signals described above, and an extension portion 62 that extends from the main body portion 61 and is electrically connected to a main board, a power supply unit, etc. (not shown).

[0069] The drive circuit board 60 is, for example, a flexible board. As shown in FIG. 6, the drive terminal row 64 and the drive circuit 63 are provided on the first board surface 60a. The drive circuit 63 is a driver IC and has, for example, 128 outputs that output drive signals to the individual terminals of the ejection channel 43. The drive circuit board 60 includes five drive circuits 63. Therefore, the drive circuit board 60 of the present embodiment can control the driving of 128×5 = 640 ejection channels 43. Note that the drive circuit board 60 may be a rigid board. Also, the drive circuit 63 may be provided on the second board surface 60b on the side opposite to the first board surface 60a of the drive circuit board 60.

[0070] In this embodiment, the first actuator row 33 includes 320 ejection channels 43, and the second actuator row 34 includes 320 ejection channels 43. Among the five drive circuits 63 provided on the drive circuit board 60 shown in FIG. 5, the drive circuit 63C arranged in the center is shared and outputs drive signals to each of the first actuator row 33 and the second actuator row 34. That is, among the 128 outputs of the drive circuit 63C arranged in the center, half of the 64 outputs output drive signals to the individual terminals of the 64 ejection channels 43 of the first actuator row 33, and the remaining half of the 64 outputs output drive signals to the individual terminals of the 64 ejection channels 43 of the second actuator row 34.

[0071] FIG. 7 is a diagram showing a state in which the flexible substrate 70 is removed from the drive circuit board 60 according to the first embodiment. FIG. 8 is a diagram showing an arrangement example of the terminals of the drive terminal row 64 according to the first embodiment. As shown in FIG. 7, the drive circuit board 60 includes a drive terminal row 64 arranged in the X direction (one direction) at the lower end. The drive terminal row 64 is electrically connected to each of the drive circuits 63 via a wiring pattern (not shown). The drive terminal row 64 is formed by arranging a plurality of terminals at a predetermined pitch. However, as shown in FIG. 8, it may be formed by arranging terminal groups 65 each including a plurality of terminals at a predetermined pitch.

[0072] In the example shown in FIG. 8, the terminal group 65 includes an individual terminal 66 electrically connected to the individual electrode of the ejection channel 43 and a common terminal 67 electrically connected to the common electrode of the ejection channel 43. That is, the drive terminal row 64 includes 640 individual terminals 66 equal in number to the individual electrodes of the 640 ejection channels 43. Further, the drive terminal row 64 includes, for example, common terminals 67 equal in number to the common electrodes of the ejection channels 43. Note that the number of common terminals 67 may be less than the number of common electrodes of the ejection channels 43 because a plurality of common electrodes are shared. Alternatively, the number of common terminals 67 may be larger (for example, one larger) than the number of common electrodes of the ejection channels 43 in order to guard the individual electrodes.

[0073] The individual terminals 66 are arranged with a first interval P1 therebetween. The common terminals 67 are arranged with a second interval P2 therebetween, where the second interval P2 is larger than the first interval P1. A second interval P2 is provided between the individual terminals 66 and the common terminals 67. That is, there is a second interval P2 between the terminal groups 65, and this is periodically repeated to form the drive terminal row 64. Note that the first interval P1 and the second interval P2 may be of the same size. That is, the drive terminal row 64 may be formed by terminals arranged at a constant pitch.

[0074] <Flexible substrate> FIG. 9 is a developed view of a flexible substrate 70 according to the first embodiment. As shown in FIG. 9, the flexible substrate 70 includes a first connection portion 71 that is electrically connected to the drive circuit substrate 60, a second connection portion 72 that is electrically connected to the first actuator row 33, and a third connection portion 73 that is electrically connected to the second actuator row 34. That is, the flexible substrate 70 has two outputs (the second connection portion 72 and the third connection portion 73) for one input (the first connection portion 71).

[0075] The second connection portion 72 and the third connection portion 73 are arranged with the first connection portion 71 therebetween. In a state where the flexible substrate 70 is opened (developed), the second connection portion 72 and the third connection portion 73 are arranged in the same plane. As shown in FIG. 6, the flexible substrate 70 forms a bent portion 74 by bending the second connection portion 72 side toward the third connection portion 73 side, and the second connection portion 72 and the third connection portion 73 are connected to the head chip 30 at substantially the same position in the Z direction. That is, a bent portion 74 bent toward the third connection portion 73 side is formed between the first connection portion 71 and the second connection portion 72 on the flexible substrate 70.

[0076] As shown in FIG. 9, the first connection portion 71 includes a first connection terminal row 81 arranged in the X direction (one direction). The first connection terminal row 81 is formed of a terminal group having the same arrangement as the drive terminal row 64 described above. The first connection terminal row 81 is electrically connected to the drive terminal row 64 by, for example, crimping or the like. As shown in FIG. 6, the first connection terminal row 81 is disposed on the second surface 70b of the flexible substrate 70 that becomes the outer peripheral side in the bent state of the flexible substrate 70.

[0077] As shown in FIG. 9, the second connection portion 72 includes a second connection terminal row 82 arranged in the X direction (one direction). The second connection terminal row 82 is electrically connected to a first portion 81A that forms half of the first connection terminal row 81 via a wiring pattern (not shown). The second connection terminal row 82 is formed longer than the first portion 81A of the first connection terminal row 81 in the X direction. That is, the interval between the terminals included in the second connection terminal row 82 is wider than the interval between the terminals of the first portion 81A of the first connection terminal row 81.

[0078] The second connection portion 72 includes a base end portion 72A that extends from a position corresponding to the first portion 81A of the first connection terminal row 81 with a constant width in a direction (Z direction) orthogonal to the X direction (one direction) in which the first connection terminal row 81 forms a row, and an extension tip portion 72B that extends further in the Z direction from the base end portion 72A and has a widened width on the second portion 81B side (-X side) of the remaining half of the first connection terminal row 81 in the X direction. The second connection terminal row 82 is provided at the upper end portion of the extension tip portion 72B.

[0079] On the +X side of the extension tip portion 72B, a notch portion 72C is formed by cutting out a portion of the flexible substrate 70 where no wiring pattern is formed on the base material for weight reduction, space saving, etc. Note that the second connection portion 72 may not have the notch portion 72C or the like, and may be formed, for example, in a sheet shape that extends in the Z direction with the same width as the first connection portion 71 in the X direction. As shown in FIG. 6, the second connection terminal row 82 is disposed on the first surface 70a of the flexible substrate 70 that becomes the inner peripheral side in the bent state of the flexible substrate 70.

[0080] As shown in Fig. 9, the third connection portion 73 includes a third connection terminal row 83 arranged in the X direction (one direction). The third connection terminal row 83 is electrically connected to the second half portion 81B of the first connection terminal row 81 via a wiring pattern (not shown). The third connection terminal row 83 is formed longer than the second portion 81B of the first connection terminal row 81 in the X direction. That is, the interval between the terminals included in the third connection terminal row 83 is wider than the interval between the terminals of the second portion 81B of the first connection terminal row 81.

[0081] The third connection portion 73 includes a base end portion 73A extending in a direction (Z direction) orthogonal to the X direction (one direction) in which the first connection terminal row 81 forms a row with a certain width from a position corresponding to the second portion 81B of the first connection terminal row 81, and an extended tip portion 73B extending further in the Z direction from the base end portion 73A and having a widened width on the first portion 81A side (+X side) of the first connection terminal row 81 in the X direction. The third connection terminal row 83 is provided at the lower end portion of the extended tip portion 73B.

[0082] On the -X side of the extended tip portion 73B, a notch portion 73C is formed by cutting out a portion where the wiring pattern of the base material of the flexible substrate 70 is not formed for weight reduction, space saving, etc. Note that the third connection portion 73 may not have the notch portion 73C or the like, and for example, it may be formed in a sheet shape extending in the Z direction with the same width as the first connection portion 71 in the X direction. As shown in Fig. 6, the third connection terminal row 83 is arranged on the first surface 70a of the flexible substrate 70 that becomes the inner peripheral side in the bent state of the flexible substrate 70.

[0083] As shown in FIG. 9, the first distance D1 between the first connection portion 71 and the second connection portion 72 is longer than the second distance D2 between the first connection portion 71 and the third connection portion 73. The difference between the first distance D1 and the second distance D2 is caused by the difference in the dimensions in the X direction between the base end portion 72A of the second connection portion 72 and the base end portion 73A of the third connection portion 73. A bending line L serving as a bending portion 74 is set in the base end portion 72A of the second connection portion 72, which is longer than the base end portion 73A of the third connection portion 73. Note that the bending line L may be marked with a mark such as a marker.

[0084] When the second connection portion 72 is bent toward the third connection portion 73 with the bending line L as a valley, as shown in FIG. 6, the second connection terminal row 82 of the second connection portion 72 and the third connection terminal row 83 of the third connection portion 73 face each other in the Y direction. The head chip 30 is sandwiched between the second connection portion 72 and the third connection portion 73, the second connection portion 72 is electrically connected to the first actuator row 33, and the third connection portion 73 is electrically connected to the second actuator row 34. Thereby, two actuator rows (the first actuator row 33 and the second actuator row 34) can be driven by a single flexible substrate 70.

[0085] As described above, the inkjet head 5 includes a head chip 30 that ejects ink, a drive circuit board 60 that outputs a drive signal for the head chip 30, and a flexible substrate 70 that electrically connects the drive circuit board 60 and the head chip 30. The head chip 30 has a first actuator row 33 and a second actuator row 34 that are driven based on a drive signal. The flexible substrate 70 has a first connection portion 71 that is electrically connected to the drive circuit board 60, a second connection portion 72 that is electrically connected to the first actuator row 33, and a third connection portion 73 that is electrically connected to the second actuator row 34.

[0086] According to the inkjet head 5 of the present embodiment, since one flexible substrate 70 has two outputs (the second connection portion 72 and the third connection portion 73) for one input (the first connection portion 71), two actuator arrays (the first actuator array 33 and the second actuator array 34) can be driven by one flexible substrate 70. For this reason, the number of flexible substrates 70 installed in the inkjet head 5 can be reduced. Therefore, the inkjet head 5 can be miniaturized and the cost can be reduced.

[0087] Further, in the inkjet head 5 of the present embodiment, the drive circuit board 60 has a drive terminal row 64 that is electrically connected to the first connection portion 71. As shown in FIG. 8, the drive terminal row 64 has a terminal group 65 composed of a plurality of terminals arranged at a predetermined pitch. According to this configuration, since one flexible substrate 70 has two outputs for one input, there is no need to provide a space between the connection row with the first actuator array 33 (the row connected to the first portion 81A shown in FIG. 9) and the connection row with the second actuator array 34 (the row connected to the second portion 81B shown in FIG. 9) in the drive terminal row 64 of the drive circuit board 60. For this reason, the drive terminal row 64 can be shortened and the dimension of the drive circuit board 60 in the X direction can be reduced, and the inkjet head 5 can be miniaturized.

[0088] Further, in the inkjet head 5 of the present embodiment, as shown in FIG. 9, a first distance D1 between the first connection portion 71 and the second connection portion 72 is longer than a second distance D2 between the first connection portion 71 and the third connection portion 73. In this way, since the first distance D1 between the first connection portion 71 and the second connection portion 72 is longer than the second distance D2 between the first connection portion 71 and the third connection portion 73, as shown in FIG. 6, the second connection portion 72 side can be bent toward the third connection portion 73 side, and the second connection portion 72 and the third connection portion 73 can be connected to the head chip 30 at substantially the same position.

[0089] Further, in the inkjet head 5 of the present embodiment, on the flexible substrate 70, a bent portion 74 bent toward the third connection portion 73 is formed between the first connection portion 71 and the second connection portion 72. According to this configuration, by bending the second connection portion 72 toward the third connection portion 73 with the bent portion 74 as a starting point, the head chip 30 can be sandwiched between the second connection portion 72 and the third connection portion 73, and the second connection portion 72 and the third connection portion 73 can be connected to the head chip 30 at substantially the same position.

[0090] Further, in the inkjet head 5 of the present embodiment, as shown in FIG. 9, on the flexible substrate 70, the second connection portion 72 and the third connection portion 73 are arranged with the first connection portion 71 interposed therebetween. According to this configuration, in a state where the flexible substrate 70 is opened, the second connection portion 72 and the third connection portion 73 are arranged in the same plane, so that it becomes easier to manufacture the flexible substrate 70.

[0091] Further, in the inkjet head 5 of the present embodiment, on the flexible substrate 70, the second connection portion 72 and the third connection portion 73 are arranged on a first surface 70a different from the first connection portion 71. According to this configuration, as shown in FIG. 6, in a state where the flexible substrate 70 is bent, each of the second connection portion 72 and the third connection portion 73 is arranged on the inner peripheral side sandwiching the head chip 30, so that the connection to the head chip 30 becomes easy. Further, since the first connection portion 71 is arranged on a second surface 70b different from the second connection portion 72 and the third connection portion 73, it is arranged on the outer peripheral side in a bent state of the flexible substrate 70, and the connection to the drive circuit board 60 becomes easy.

[0092] Further, in the inkjet head 5 of the present embodiment, as shown in FIG. 9, the first connection portion 71 has a first connection terminal row 81 arranged in one direction (X direction). According to this configuration, since the first connection terminal row 81 of the first connection portion 71 is arranged in one direction, the connection such as crimping to the drive circuit board 60 becomes easy.

[0093] Also, in the inkjet head 5 of the present embodiment, the first connection terminal row 81 has a first portion 81A electrically connected to the second connection portion 72 and a second portion 81B electrically connected to the third connection portion 73. The second connection portion 72 has a second connection terminal row 82 formed longer than the first portion 81A of the first connection terminal row 81 in one direction. The third connection portion 73 has a third connection terminal row 83 formed longer than the second portion 81B of the first connection terminal row 81 in one direction. According to this configuration, in the second connection portion 72 and the third connection portion 73, the connection terminals can be connected to the head chip 30 with a wider interval than the first connection portion 71.

[0094] Also, in the inkjet head 5 of the present embodiment, the second connection terminal row 82 extends toward the second portion 81B side of the first connection terminal row 81 in one direction, and the third connection terminal row 83 extends toward the first portion 81A side of the first connection terminal row 81 in one direction. According to this configuration, in the second connection portion 72 and the third connection portion 73, even when the interval between the connection terminals is widened compared to the first connection portion 71, the formation ranges of the second connection terminal row 82 and the third connection terminal row 83 overlap in one direction so that they overlap when the flexible substrate 70 is bent. Thus, it is not necessary to widen the width of the flexible substrate 70, and the inkjet head 5 can be miniaturized.

[0095] The printer 1 according to the present embodiment includes the above-described inkjet head 5. According to this printer 1, a small and low-cost product can be provided.

[0096] (Second Embodiment) Next, a second embodiment of the present invention will be described. In the following description, the same or equivalent configurations as those in the above-described embodiment are denoted by the same reference numerals, and the description thereof is simplified or omitted.

[0097] FIG. 10 is a developed view of the flexible substrate 70 according to the second embodiment. As shown in FIG. 10, in the second embodiment, a sheet-like conductive pattern 90 (so-called solid pattern) is formed in a region around a bending line L that becomes a bent portion 74 of the flexible substrate 70. The conductive pattern 90 extends parallel to the X direction with the bending line L interposed therebetween and across the base end portion 72A.

[0098] The conductive pattern 90 makes the bent portion 74 of the flexible substrate 70 relatively easier to bend compared to the surrounding region. That is, the bent portion 74 has a lower rigidity when bent relatively compared to the surrounding region. The conductive pattern 90 is preferably electrically grounded. Thereby, not only can the rigidity of the flexible substrate 70 be adjusted in the conductive pattern 90, but also an electrical function can be added. The conductive pattern 90 may be formed on at least one of the first surface 70a and the second surface 70b of the flexible substrate 70. Further, when there are three or more conductive layers in the flexible substrate 70, the conductive pattern 90 may be formed in any layer different from the layer in which the signal wiring is formed.

[0099] Thus, according to the inkjet head 5 of the second embodiment having the above configuration, the bent portion 74 has a lower rigidity when bent relatively compared to the surrounding region. According to this configuration, since the bent portion 74 is relatively easier to bend compared to the surrounding region, the bending position of the flexible substrate 70 can be adjusted to the designed position.

[0100] Also, in the inkjet head 5 of the second embodiment, a sheet-like conductive pattern 90 is formed in the surrounding region. According to this configuration, by forming the sheet-like conductive pattern 90 in the region around the bent portion 74, the region around the bent portion 74 can be made difficult to bend, and the flexible substrate 70 can be relatively easily bent at the bent portion 74.

[0101] (Third Embodiment) Next, a third embodiment of the present invention will be described. In the following description, the same or equivalent components as those in the above-described embodiments are denoted by the same reference numerals, and the description thereof will be simplified or omitted.

[0102] FIG. 11 is a developed view of a flexible substrate 70 according to the third embodiment. As shown in FIG. 11, in the third embodiment, a sheet-like conductive pattern 90 is formed in a region including the bent portion 74 of the flexible substrate 70. The conductive pattern 90 has a constant width in the Z direction and extends in the X direction so as to cross the base end portion 72A.

[0103] The conductive pattern 90 is configured to make it easier to maintain the shape after bending relative to other regions of the flexible substrate 70 in the flexible substrate 70. That is, by forming the conductive pattern 90 having a certain thickness in the range including the bent portion 74, bending the conductive pattern 90 together with the flexible substrate 70, and plastically deforming only the conductive pattern 90 (the base material of the flexible substrate 70 itself is only bent into a U shape without undergoing plastic deformation such as bending), it is possible to suppress the restoring deformation of the flexible substrate 70 having a certain resilience. Note that the conductive pattern 90 may be formed on at least one of the first surface 70a and the second surface 70b of the flexible substrate 70. Preferably, the conductive pattern 90 is formed on the first surface 70a which has a smaller radius of curvature when bent and is more easily plastically deformed than the second surface 70b.

[0104] Thus, according to the inkjet head 5 of the third embodiment having the above configuration, the bent portion 74 is more likely to maintain the shape after being bent relative to other regions of the flexible substrate 70. According to this configuration, since the bent portion 74 is more likely to maintain the shape after being bent relative to other regions of the flexible substrate 70, the bent state of the flexible substrate 70 can be maintained, and as shown in FIG. 6, the elastic reaction force (restoring force) of the base material of the flexible substrate 70 applied to the contact point of the second connection portion 72 can be reduced.

[0105] Further, in the inkjet head 5 of the present embodiment, a sheet-like conductive pattern 90 is formed on the bent portion 74. According to this configuration, by forming the sheet-like conductive pattern 90 on the bent portion 74, the bent state of the flexible substrate 70 can be maintained, and the elastic reaction force of the base material of the flexible substrate 70 applied to the contact point of the second connection portion 72 can be reduced.

[0106] In addition, in the third embodiment, a modification as shown in FIG. 12 can be adopted.

[0107] FIG. 12 is a developed view of the flexible substrate 70 according to a modification of the third embodiment. In the conductive pattern 90 shown in FIG. 12, a gap 91 extending along the bending line L of the bent portion 74 is formed. The gap 91 is formed in a slit shape that intermittently extends in the X direction. According to this configuration, the gap 91 of the conductive pattern 90 makes it easier to bend the bent portion 74 along the bending line L. Therefore, the bending position of the flexible substrate 70 can be adjusted to the designed position, and as a result, the workability during assembly can be improved. In addition, by the plastic deformation of the intermittent portions between the gaps 91 of the conductive pattern 90, the bent state of the flexible substrate 70 can be maintained, and the elastic reaction force of the base material of the flexible substrate 70 applied to the contact point of the second connection portion 72 can be reduced. That is, according to a modification of the third embodiment, in addition to the effects of the third embodiment, the effects of the second embodiment can be obtained.

[0108] As described above, the preferred embodiments of the present disclosure have been described and explained. However, it should be understood that these are exemplary of the present disclosure and should not be considered as limiting. Additions, omissions, substitutions, and other changes can be made without departing from the scope of the present disclosure. Therefore, the present disclosure should not be regarded as limited by the foregoing description, but is limited by the scope of the claims.

[0109] For example, in the above-described embodiment, as an example of the liquid ejection recording apparatus, an inkjet printer has been described, but it is not limited to printers. For example, it may be a fax machine, an on-demand printer, or the like. In the above-described embodiment, the configuration in which the inkjet head moves relative to the recording medium during printing (so-called shuttle mechanism) has been described as an example, but it is not limited to this configuration. The configuration according to the present disclosure may be adopted in a configuration in which the recording medium is moved relative to the inkjet head with the inkjet head fixed (so-called fixed head mechanism). In the above-described embodiment, the case where the recording medium P is paper has been described, but it is not limited to this configuration. The recording medium P is not limited to paper, and may be a metal material, a resin material, or may be food or the like. In the above-described embodiment, the configuration in which the liquid ejection head is mounted on the liquid ejection recording apparatus has been described, but it is not limited to this configuration. That is, the liquid ejected from the liquid ejection head is not limited to that which lands on the recording medium, and may be, for example, a chemical solution to be blended in a preparation, a food additive such as a seasoning or a fragrance added to food, an aromatic agent ejected into the air, or the like. In the above-described embodiment, the configuration in which the Z direction coincides with the gravitational direction has been described, but it is not limited to this configuration only, and the Z direction may be along the horizontal direction. In the above-described embodiment, the configuration in which one direction coincides with the X direction has been described, but it is not limited to this configuration. One direction may be defined separately from the X direction.

Explanation of Reference Numerals

[0110] 1... Printer (Liquid Ejection Recording Apparatus) 5... Inkjet Head (Liquid Ejection Head) 30... Head Chip (Ejection Portion) 33... First Actuator Row 34... Second Actuator Row 43... Discharge Channel 44... Non-Discharge Channel 60... Drive Circuit Board 63... Drive Circuit 64... Drive Terminal Row 65…Terminal group 70…Flexible substrate 70a…First surface 70b…Second surface 71…First connection part 72…Second connection part 73…Third connection part 74…Bending part 81…First connection terminal row 81A…First part 81B…Second part 82…Second connection terminal row 83…Third connection terminal row 90…Conductive pattern 91…Gap D1…First distance D2…Second distance IC…Driver L…Bending line

Claims

1. An injection unit that injects a liquid, A drive circuit board that outputs a drive signal for the injection unit, A flexible board that electrically connects the drive circuit board and the injection unit, and is provided with: The injection unit has a first actuator row and a second actuator row that are driven based on the drive signal, The flexible board, A first connection part that is electrically connected to the drive circuit board, A second connection part that is electrically connected to the first actuator row, A third connection part that is electrically connected to the second actuator row, and a liquid injection head characterized by this.

2. The drive circuit board has a drive terminal row that is electrically connected to the first connection part, The drive terminal row is characterized in that a terminal group composed of a plurality of terminals is arranged at a predetermined pitch. The liquid injection head according to Claim 1.

3. In the flexible board, a first distance between the first connection part and the second connection part is longer than a second distance between the first connection part and the third connection part. The liquid injection head according to Claim 1 or 2, characterized by this.

4. On the flexible board, a bent part that is bent toward the third connection part side is formed between the first connection part and the second connection part. The liquid injection head according to Claim 3, characterized by this.

5. The bent part is characterized in that its rigidity when bent is relatively lower than that of the surrounding area. The liquid injection head according to Claim 4.

6. A sheet-shaped conductive pattern is formed in the surrounding area. The liquid injection head according to Claim 5, characterized by this.

7. The bent part is characterized in that it is easier to maintain the shape after being bent compared to other areas of the flexible board. The liquid injection head according to Claim 4.

8. A sheet-shaped conductive pattern is formed in the bent part. The liquid injection head according to Claim 7, characterized by this.

9. The conductive pattern is characterized in that a gap extending along the bending line of the bent part is formed. The liquid injection head according to Claim 8.

10. In the flexible board, the second connection part and the third connection part are arranged with the first connection part interposed therebetween. The liquid injection head according to any one of Claims 1 to 9, characterized by this.

11. In the flexible substrate, the second connection portion and the third connection portion are arranged on a surface different from the first connection portion. The liquid ejection head according to any one of claims 1 to 10, characterized in that.

12. The first connection portion has a first connection terminal row arranged in one direction. The liquid ejection head according to any one of claims 1 to 11, characterized in that.

13. The first connection terminal row is A first portion electrically connected to the second connection portion; And a second portion electrically connected to the third connection portion. The second connection portion has a second connection terminal row formed longer than the first portion of the first connection terminal row in the one direction. The third connection portion has a third connection terminal row formed longer than the second portion of the first connection terminal row in the one direction. The liquid ejection head according to claim 12, characterized in that.

14. The second connection terminal row extends on the second portion side of the first connection terminal row in the one direction. The third connection terminal row extends on the first portion side of the first connection terminal row in the one direction. The liquid ejection head according to claim 13, characterized in that.

15. A liquid ejection recording apparatus comprising the liquid ejection head according to any one of claims 1 to 14.

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