JP7705328B2 - Liquid jet head and liquid jet recording apparatus - Google Patents

Description

This disclosure relates to a liquid jet head and a liquid jet recording device.

The following Patent Document 1 discloses a liquid ejection head including a head section (ejection section) 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 section and supplying a drive signal to the head section for driving the first channel row, and a second flexible substrate having 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, and the fourth terminal row being electrically connected to the head section and supplying a drive signal to the head section for driving the second channel row.

JP 2016-55546 A

In the conventional liquid jet head described above, the same number of flexible boards as the number of actuator rows were required to electrically connect the drive circuit board having the drive circuit to each row of actuator rows. This resulted in a large number of flexible boards being installed in the liquid jet head, which was an obstacle to miniaturization and cost reduction.

This disclosure was made in consideration of the above problems, and aims to reduce the number of flexible substrates installed in a liquid ejection head.

(1) A liquid ejection head according to one aspect of the present disclosure includes an ejection unit that ejects liquid, a drive circuit board that outputs a drive signal for the ejection unit, and a flexible substrate that electrically connects the drive circuit board and the ejection unit, the ejection unit having a first actuator row and a second actuator row that are driven based on the drive signal, and the flexible substrate having 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.

In the liquid jet head according to this aspect, one flexible substrate has one input (first connection portion) and two outputs (second connection portion and third connection portion), so two actuator rows can be driven with one flexible substrate. This makes it possible to reduce the number of flexible substrates installed in the liquid jet head.

(2) In the liquid jet head of aspect (1), the drive circuit board may have a drive terminal array electrically connected to the first connection portion, and the drive terminal array may be a terminal group consisting of a plurality of terminals arranged at a predetermined pitch.

In this case, one flexible board has two outputs for one input, so there is no need to provide a space between the connection row to the first actuator row and the connection row to the second actuator row in the drive terminal row of the drive circuit board. This makes it possible to shorten the drive terminal row and reduce the size of the drive circuit board, thereby miniaturizing the liquid ejection head.

(3) In the liquid jet head of aspect (1) or (2), in the flexible substrate, a first distance between the first connection portion and the second connection portion may be longer than a second distance between the first connection portion and the third connection portion.

In this case, since the first distance between the first connection part and the second connection part is longer than the second distance between the first connection part and the third connection part, the second connection part and the third connection part can be connected to the injection part at approximately the same position by bending the second connection part side toward the third connection part side.

(4) In the liquid jet head of aspect (3), the flexible substrate may have a bent portion between the first connection portion and the second connection portion that is bent toward the third connection portion.

In this case, by bending the second connection part toward the third connection part starting from the bent part, the injection part is sandwiched between the second connection part and the third connection part, and the second connection part and the third connection part can be connected to the injection part at approximately the same position.

(5) In the liquid jet head of aspect (4), the bent portion may have a relatively low rigidity when bent compared to the surrounding area.

In this case, the bend is easier to bend than the surrounding areas, so the bending position of the flexible substrate can be aligned to the designed position.

(6) In the liquid jet head of aspect (5), a sheet-like conductive pattern may be formed in the surrounding area.

In this case, by forming a sheet-like conductive pattern in the area surrounding the bend, the area surrounding the bend can be made more difficult to bend, making the flexible substrate relatively easier to bend at the bend.

(7) In the liquid jet head of aspect (4), the bent portion may be relatively easy to maintain the shape after bending compared to other areas of the flexible substrate.

In this case, the bent portion is relatively easier to maintain its shape after bending compared to other areas of the flexible substrate, so the bent state of the flexible substrate can be maintained, and the elastic reaction force of the base material of the flexible substrate acting on the contact point of the second connection portion can be reduced.

(8) In the liquid jet head of aspect (7), a sheet-like conductive pattern may be formed on the folded portion.

In this case, by forming a sheet-like conductive pattern in the area 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 acting on the contact point of the second connection portion can be reduced.

(9) In the liquid jet head of aspect (8), the conductive pattern may have a gap formed therein that extends along the bending line of the bending portion.

In this case, the gaps in the conductive pattern make it easier to fold the bend along the fold line. This allows the bending position of the flexible board to be aligned to the designed position, thereby improving workability during assembly.

(10) In the liquid jet head according to any one of the aspects (1) to (9), the second connection portion and the third connection portion may be arranged on the flexible substrate with the first connection portion sandwiched therebetween.

In this case, when the flexible substrate is opened, the second connection portion and the third connection portion are arranged on the same plane, making it easier to manufacture the flexible substrate.

(11) In the liquid jet head according to any one of (1) to (10), the second connection portion and the third connection portion may be disposed on a different surface of the flexible substrate from the first connection portion.

In this case, when the flexible substrate is folded, the second and third connection parts are positioned on the inner periphery side sandwiching the ejection part, making it easy to connect to the ejection part. Also, since the first connection part is positioned on a different surface from the second and third connection parts, it is positioned on the outer periphery side when the flexible substrate is folded, making it easy to connect to the drive circuit board.

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

In this case, the first connection terminal row of the first connection portion is arranged in one direction, making it easier to connect to the drive circuit board by crimping or the like.

(13) In the liquid jet head of aspect (12), the first connection terminal row may have 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 may have a second connection terminal row formed longer in the one direction than the first portion of the first connection terminal row, and the third connection portion may have a third connection terminal row formed longer in the one direction than the second portion of the first connection terminal row.

In this case, the second and third connection parts can be connected to the injection part with a wider spacing between the connection terminals than the first connection part.

(14) In the liquid jet head of aspect (13), the second connection terminal row may extend toward the second portion of the first connection terminal row in the one direction, and the third connection terminal row may extend toward the first portion of the first connection terminal row in the one direction.

In this case, even if the spacing between the connection terminals in the second and third connection sections is wider than in the first connection section, the formation ranges of the second and third connection terminal rows are overlapped in one direction so that they overlap when the flexible substrate is folded, making it unnecessary to widen the width of the flexible substrate and enabling the liquid ejection head to be made smaller.

(15) A liquid jet recording device according to one aspect of the present disclosure includes a liquid jet head according to any one of aspects (1) to (14).

The liquid jet recording device according to this aspect can provide a small, low-cost product.

According to one aspect of the present disclosure, the number of flexible substrates installed in a liquid ejection head can be reduced.

1 is a schematic configuration diagram of a printer according to a first embodiment. 1 is a perspective view of an inkjet head according to a first embodiment; 1 is an exploded perspective view of an inkjet head according to a first embodiment; FIG. 2 is a perspective view of a drive circuit board according to the first embodiment. FIG. 2 is a schematic configuration diagram of a drive circuit board according to the first embodiment. 6 is a cross-sectional view taken along line VI-VI in FIG. 5. 5 is a diagram showing a state in which a flexible substrate is removed from the drive circuit board according to the first embodiment. FIG. 4A to 4C are diagrams illustrating an example of the arrangement of terminals in a driving terminal row according to the first embodiment. FIG. 2 is a development view of the flexible substrate according to the first embodiment. FIG. 11 is a development view of a flexible substrate according to a second embodiment. FIG. 13 is a development view of a flexible substrate according to a third embodiment. FIG. 13 is a development view of a flexible substrate according to a modified example of the third embodiment.

Embodiments of the present disclosure will be described below with reference to the drawings.

In the embodiments and variations described below, the same reference numerals may be used to designate corresponding configurations, and the description may be omitted. In addition, in the following description, expressions indicating relative or absolute arrangements, such as "parallel," "orthogonal," "center," and "coaxial," do not only strictly indicate such arrangements, but also indicate a state in which there is a relative displacement with a tolerance or an angle or distance that provides the same function.

In the following embodiment, an inkjet printer (hereinafter simply called a printer) that uses ink (liquid) to record on a recording medium will be used as an example. Note that in the drawings used in the following description, the scale of each component has been appropriately changed so that each component is of a recognizable size.

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

In the following explanation, an X, Y, Z Cartesian coordinate system will be used as necessary. The X direction is the transport direction (sub-scanning direction) of the recording medium P (e.g., paper, etc.). The Y direction is the scanning direction (main scanning direction) of the scanning mechanism 6. The Z direction is the height direction (gravity direction) perpendicular to the X and Y directions.

In the following explanation, the X, Y, and Z directions are described with the arrows in the figures as the plus (+) side and the opposite side as the minus (-) side. In this embodiment, the +Z side corresponds to the upward direction of gravity, and the -Z side corresponds to the downward direction of gravity.

The transport mechanisms 2 and 3 transport the recording medium P to the +X side. The transport mechanisms 2 and 3 each include a pair of rollers 11 and 12 that extend in the Y direction, for example. The ink supply mechanism 4 includes an ink tank 15 that contains ink, and an ink pipe 16 that connects the ink tank 15 to the inkjet head 5.

The ink tanks 15 each contain four colors of ink, for example, yellow, magenta, cyan, and black. A plurality of inkjet heads 5 are provided, and each is configured to be able to eject ink of the four colors, yellow, magenta, cyan, and black, according to the ink tank 15 connected to it. Note that the ink contained in the ink tanks 15 can also be a water-based ink (conductive ink) that uses water as a solvent.

The scanning mechanism 6 causes the inkjet head 5 to scan back and forth 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. During the printing operation on the recording medium P, the inkjet head 5 moves back and forth in the Y direction while mounted on the carriage 23.

<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 ink supplied. Therefore, in the following description, one inkjet head 5 will be described as an example, and descriptions 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 (ejection portion) in which first nozzle holes 31 and second nozzle holes 32 for ejecting ink are formed in two rows.

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

The first actuator row 33 is a so-called edge shoot type head chip that ejects ink from the tip of the ejection channel 43 in the channel extension direction (Z direction). The first actuator row 33 is configured by stacking a first actuator plate 41 and a first cover plate 42 in the Y direction.

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 a ceramic substrate made of PZT (lead zirconate titanate) or the like. The first actuator plate 41 may also be formed by stacking two piezoelectric substrates whose polarization directions are different in the Y direction (so-called chevron type).

On the surface of the first actuator plate 41 (the surface facing the first cover plate 42), ejection channels 43 and non-ejection channels 44 are arranged alternately and spaced apart in the X direction. The ejection channels 43 and non-ejection channels 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 ejection channel 43 and non-ejection channel 44 is separated in the X direction by a drive wall 45 made of the first actuator plate 41.

The first cover plate 42 is formed in a rectangular shape when viewed from the Y direction. The first cover plate 42 is joined to the surface of the first actuator plate 41 with the upper end of the first actuator plate 41 exposed. The first cover plate 42 has a common ink chamber 46 and a number of slits 47.

The common ink chamber 46 is formed at a position equivalent to the upper end of the ejection channel 43 in the Z direction. The common ink chamber 46 is recessed toward the rear 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 via the ink supply mechanism 4 (see FIG. 1) described above.

The slits 47 are formed in the common ink chamber 46 at positions facing the ejection channels 43 in the Y direction. These slits 47 connect the common ink chamber 46 to each of the ejection channels 43. On the other hand, the non-ejection channels 44 do not connect to the common ink chamber 46.

The second actuator row 34 is configured by stacking 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, the same reference numerals as the first actuator row 33 may be used to designate the same components in the second actuator row 34 as those in the first actuator row 33, and the description may be omitted.

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

The nozzle cap 36 is a plate-like member whose outer shape in a plan view from the Z direction is formed into a rectangular shape. The nozzle cap 36 is formed with a fitting hole 55 penetrating the nozzle cap 36 in the Z direction. The first actuator row 33 and the second actuator row 34 are fitted together in 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 so that their bottom end faces are flush with the bottom end face of the nozzle cap 36.

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, for example by adhesive. 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, etc.

The nozzle plate 35 has a plurality of nozzle rows (first nozzle row 56 and second nozzle row 57) formed therein, which extend in the X direction. The first nozzle row 56 and the second nozzle row 57 extend parallel to each other and are spaced apart in the X direction.

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 formed separately in the nozzle plate 35 at positions that face the ejection channels 43 of the first actuator row 33 in the Z direction. In other words, the first nozzle holes 31 are aligned in a straight line at intervals in the X direction.

The second nozzle row 57 has second nozzle holes 32 penetrating the nozzle plate 35 in the Z direction. The second nozzle holes 32 are formed separately in the nozzle plate 35 at positions facing the ejection channels 43 of the second actuator row 34 in the Z direction. That is, the second nozzle holes 32 are aligned in a straight line at intervals in the X direction. The first nozzle holes 31 and the second nozzle holes 32 are formed in a tapered shape that gradually narrows from top to bottom.

2 and 3, the nozzle guard 37 is formed by pressing a plate material such as SUS, etc. The nozzle guard 37 is formed in a box shape that opens upward.
The nozzle guard 37 covers the nozzle plate 35 from below when fitted onto the nozzle cap 36 .

In the nozzle guard 37, exposure holes (first exposure hole 58 and second exposure hole 59) that penetrate the nozzle guard 37 in the Z direction are formed in the portions that face the first nozzle row 56 and the second nozzle row 57 in the Z direction. The first exposure hole 58 and the second exposure hole 59 are formed in the shape of a slit that extends in the X direction. The first nozzle row 56 and the second nozzle row 57 are exposed to the outside through the corresponding first exposure hole 58 and second exposure hole 59.

The ejection channel 43 is sandwiched between a pair of drive walls 45 on both sides in the X direction. The ejection channel 43 is filled with ink. On the other hand, the non-ejection channel 44 is not filled with ink. An electrode portion (not shown) is formed on the drive wall 45 by deposition or the like. The electrode portion deforms the drive wall 45 by the piezoelectric sliding effect when a drive signal is input from a drive circuit board 60 shown in Figures 5 and 6 (described later) via a flexible substrate 70.

The electrode section bends and deforms a pair of drive walls 45 that sandwich the ejection channel 43 in the X direction into a V-shape so as to move them closer to or apart from each other. The electrode section includes individual electrodes (not shown) provided for each ejection channel 43, and a common electrode (not shown) commonly connected to each of the ejection channels 43. The terminals of the common electrode and the individual electrodes extend to the upper ends of the first actuator plate 41 and the second actuator plate 51.

The terminal of the common electrode and the terminal of the individual electrodes are electrically connected to the drive circuit board 60 via a flexible substrate 70 (described later) that is connected to the upper ends of the first actuator plate 41 and the second actuator plate 51. When a drive signal is input (a positive potential is applied) from the control unit to the individual electrodes, with the common electrode at the reference potential GND, the pair of drive walls 45 are bent and deformed into a V shape so as to move away from each other. In other words, the pair of drive walls 45 deform so as to expand the volume of the ejection channel 43.

After the volume of each ejection channel 43 is increased, the voltage applied between the common electrode and the individual electrode is set to zero. Then, the pair of driving walls 45 is restored, and the volume of the ejection channel 43, which was once increased, returns to its original volume. This increases the pressure inside the ejection channel 43, and pressurizes the ink. As a result, the ink is ejected in the form of droplets through the first nozzle hole 31 and the second nozzle hole 32. The ejected ink lands on the recording medium P shown in FIG. 1, thereby recording characters, images, etc. on the recording medium P.
In addition, a configuration in which a positive potential is applied from the control unit to the individual electrodes to increase the volume of each ejection channel 43, the individual electrodes are then connected to a reference potential GND to return the volume of each ejection channel 43 to its original state, and then a negative potential is applied to the individual electrodes to reduce the volume of each ejection channel 43 and push out the ink may be used.

<Drive circuit board>
Fig. 4 is a perspective view of the 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 line VI-VI shown in Fig. 5.
As shown in Figures 4 and 5, the drive circuit board 60 includes a main body portion 61 having a plurality of drive circuits 63 that output the above-mentioned drive signals, and an extension portion 62 extending from the main body portion 61 and electrically connected to a main board, a power supply unit, etc. (not shown).

The drive circuit board 60 is, for example, a flexible board, and as shown in FIG. 6, has a drive terminal row 64 and a drive circuit 63 on the first plate surface 60a. The drive circuit 63 is a driver IC, and has, for example, 128 outputs that output drive signals to individual terminals of the ejection channels 43. The drive circuit board 60 has five drive circuits 63. Therefore, the drive circuit board 60 of this embodiment can control the drive of 128 x 5 = 640 ejection channels 43. The drive circuit board 60 may be a rigid board. The drive circuit 63 may be provided on the second plate surface 60b opposite to the first plate surface 60a of the drive circuit board 60.

In this embodiment, the first actuator column 33 has 320 ejection channels 43, and the second actuator column 34 has 320 ejection channels 43. Of the five drive circuits 63 provided on the drive circuit board 60 shown in FIG. 5, the drive circuit 63C located in the center is shared and outputs drive signals to both the first actuator column 33 and the second actuator column 34. That is, of the 128 outputs of the drive circuit 63C located in the center, half (64 outputs) output drive signals to the individual terminals of the 64 ejection channels 43 of the first actuator column 33, and the remaining half (64 outputs) output drive signals to the individual terminals of the 64 ejection channels 43 of the second actuator column 34.

Fig. 7 is a diagram showing a state in which the flexible substrate 70 is removed from the drive circuit substrate 60 according to the first embodiment. Fig. 8 is a diagram showing an example of the arrangement of terminals in the drive terminal array 64 according to the first embodiment.
As shown in Fig. 7, the drive circuit board 60 has a drive terminal row 64 arranged in the X direction (one direction) at the bottom 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, but may also be formed by arranging a terminal group 65 consisting of a plurality of terminals at a predetermined pitch as shown in Fig. 8.

8, the terminal group 65 includes individual terminals 66 electrically connected to the individual electrodes of the ejection channels 43 and common terminals 67 electrically connected to the common electrodes of the ejection channels 43. That is, the drive terminal array 64 includes 640 individual terminals 66, the same number as the 640 individual electrodes of the ejection channels 43. The drive terminal array 64 also includes, for example, the same number of common terminals 67 as the common electrodes of the ejection channels 43. Note that the number of common terminals 67 may be fewer than the number of common electrodes of the ejection channels 43, with multiple common electrodes being commonized. Alternatively, in order to guard the individual electrodes, the number of common terminals 67 may be greater than the number of common electrodes of the ejection channels 43 (for example, one more).

The individual terminals 66 are arranged at a first interval P1. The common terminals 67 are arranged at a second interval P2 that is larger than the first interval P1. The second interval P2 is provided between the individual terminals 66 and the common terminal 67. In other words, the second interval P2 is provided between the terminal groups 65, and this is repeated periodically to form the drive terminal row 64. Note that the first interval P1 and the second interval P2 may be the same size. In other words, the drive terminal row 64 may be formed of terminals arranged at a constant pitch.

<Flexible substrate>
FIG. 9 is a development view of the flexible substrate 70 according to the first embodiment.
9, the flexible substrate 70 includes a first connection portion 71 electrically connected to the drive circuit substrate 60, a second connection portion 72 electrically connected to the first actuator row 33, and a third connection portion 73 electrically connected to the second actuator row 34. In other words, the flexible substrate 70 includes one input (first connection portion 71) and two outputs (second connection portion 72 and third connection portion 73).

The second connection portion 72 and the third connection portion 73 are arranged with the first connection portion 71 in between. When the flexible substrate 70 is in an open (unfolded) state, the second connection portion 72 and the third connection portion 73 are arranged on the same plane. As shown in FIG. 6, the flexible substrate 70 is bent from the second connection portion 72 side toward the third connection portion 73 side to form a bent portion 74, and the second connection portion 72 and the third connection portion 73 are connected to the head chip 30 at approximately the same position in the Z direction. In other words, the flexible substrate 70 has a bent portion 74 bent toward the third connection portion 73 side between the first connection portion 71 and the second connection portion 72.

As shown in FIG. 9, the first connection portion 71 has a first connection terminal row 81 arranged in the X direction (one direction). The first connection terminal row 81 is formed of a group of terminals arranged in the same manner as the drive terminal row 64 described above. The first connection terminal row 81 is electrically connected to the drive terminal row 64, for example, by crimping. As shown in FIG. 6, this first connection terminal row 81 is arranged on the second surface 70b of the flexible substrate 70, which is on the outer periphery when the flexible substrate 70 is in a folded state.

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 in the X direction than the first portion 81A of the first connection terminal row 81. In other words, the spacing between the terminals included in the second connection terminal row 82 is wider than the spacing between the terminals in the first portion 81A of the first connection terminal row 81.

The second connection portion 72 has a base end 72A that extends at a constant width from a position corresponding to the first portion 81A of the first connection terminal row 81 in a direction (Z direction) perpendicular to the X direction (one direction) in which the first connection terminal row 81 is arranged, and an extended tip portion 72B that extends further in the Z direction from the base end 72A and has a wider width in the X direction toward the second portion 81B side (-X side) of the remaining half of the first connection terminal row 81. The second connection terminal row 82 is provided at the upper end of the extended tip portion 72B.

A cutout portion 72C is formed on the +X side of the extended tip portion 72B by cutting out a portion of the flexible substrate 70 where no wiring pattern is formed in the base material in order to reduce weight and save space. The second connection portion 72 does not need to have the cutout portion 72C, and may be formed, for example, in a sheet shape extending in the Z direction with the same width in the X direction as the first connection portion 71. The second connection terminal row 82 is arranged on the first surface 70a of the flexible substrate 70, which is on the inner periphery side when the flexible substrate 70 is folded, as shown in FIG. 6.

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 remaining half, the second portion 81B, of the first connection terminal row 81 via a wiring pattern (not shown). The third connection terminal row 83 is formed longer in the X direction than the second portion 81B of the first connection terminal row 81. In other words, the spacing between the terminals included in the third connection terminal row 83 is wider than the spacing between the terminals of the second portion 81B of the first connection terminal row 81.

The third connection portion 73 has a base end 73A that extends from a position corresponding to the second portion 81B of the first connection terminal row 81 with a certain width in a direction (Z direction) perpendicular to the X direction (one direction) in which the first connection terminal row 81 is arranged, and an extended tip portion 73B that extends further in the Z direction from the base end 73A and has a wider width in the X direction toward the first portion 81A of the first connection terminal row 81 (+X side). The third connection terminal row 83 is provided at the lower end of the extended tip portion 73B.

A notch 73C is formed on the -X side of the extended tip 73B by cutting out a portion of the base material of the flexible substrate 70 where the wiring pattern is not formed in order to reduce weight and save space. The third connection portion 73 does not need to have the notch 73C, and may be formed, for example, in a sheet shape extending in the Z direction with the same width in the X direction as the first connection portion 71. The third connection terminal row 83 is arranged on the first surface 70a of the flexible substrate 70, which is on the inner periphery when the flexible substrate 70 is folded, as shown in FIG. 6.

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 arises from the difference in the X-direction dimension 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 fold line L that becomes the fold portion 74 is set at 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. The fold line L may be marked with a marker or other marking.

When the second connection portion 72 is folded toward the third connection portion 73 with the folding line L as a valley, 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, as shown in FIG. 6. The head chip 30 is sandwiched between the second connection portion 72 and the third connection portion 73, and 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. This allows two actuator rows (the first actuator row 33 and the second actuator row 34) to be driven by a single flexible substrate 70.

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 board 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 the drive signal. The flexible board 70 has a first connection portion 71 electrically connected to the drive circuit board 60, a second connection portion 72 electrically connected to the first actuator row 33, and a third connection portion 73 electrically connected to the second actuator row 34.

According to the inkjet head 5 of this embodiment, one flexible substrate 70 has one input (first connection portion 71) and two outputs (second connection portion 72 and third connection portion 73), so that one flexible substrate 70 can drive two actuator rows (first actuator row 33 and second actuator row 34). This makes it possible to reduce the number of flexible substrates 70 installed in the inkjet head 5. This allows the inkjet head 5 to be made smaller and less expensive.

In the inkjet head 5 of this embodiment, the drive circuit board 60 has a drive terminal row 64 electrically connected to the first connection portion 71, and the drive terminal row 64 has a terminal group 65 consisting of a plurality of terminals arranged at a predetermined pitch, as shown in FIG. 8. With this configuration, one flexible board 70 has two outputs for one input, so that in the drive terminal row 64 of the drive circuit board 60, it is not necessary to provide a space between the connection row with the first actuator row 33 (the row connected to the first part 81A shown in FIG. 9) and the connection row with the second actuator row 34 (the row connected to the second part 81B shown in FIG. 9). This makes it possible to shorten the drive terminal row 64 and reduce the dimension of the drive circuit board 60 in the X direction, thereby making the inkjet head 5 more compact.

In addition, in the inkjet head 5 of this embodiment, 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. 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 approximately the same position.

In addition, in the inkjet head 5 of this embodiment, the flexible substrate 70 has a bent portion 74 bent toward the third connection portion 73 between the first connection portion 71 and the second connection portion 72. With this configuration, by bending the second connection portion 72 toward the third connection portion 73 from the bent portion 74 as a starting point, the head chip 30 is 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 approximately the same position.

In addition, in the inkjet head 5 of this embodiment, as shown in FIG. 9, the second connection portion 72 and the third connection portion 73 are arranged on either side of the first connection portion 71 in the flexible substrate 70. With this configuration, when the flexible substrate 70 is opened, the second connection portion 72 and the third connection portion 73 are arranged on the same plane, making it easier to manufacture the flexible substrate 70.

In the inkjet head 5 of this embodiment, the second connection portion 72 and the third connection portion 73 of the flexible substrate 70 are arranged on a first surface 70a different from the first connection portion 71. With this configuration, as shown in FIG. 6, when the flexible substrate 70 is folded, the second connection portion 72 and the third connection portion 73 are arranged on the inner periphery side sandwiching the head chip 30, making it easy to connect to the head chip 30. In addition, 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, so that when the flexible substrate 70 is folded, it is arranged on the outer periphery side, making it easy to connect to the drive circuit board 60.

In addition, in the inkjet head 5 of this embodiment, as shown in FIG. 9, the first connection portion 71 has a first connection terminal row 81 arranged in one direction (X direction). With this configuration, the first connection terminal row 81 of the first connection portion 71 is arranged in one direction, which makes it easy to connect to the drive circuit board 60 by crimping or the like.

In the inkjet head 5 of this 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 in one direction than the first portion 81A of the first connection terminal row 81, and the third connection portion 73 has a third connection terminal row 83 formed longer in one direction than the second portion 81B of the first connection terminal row 81. With this configuration, the second connection portion 72 and the third connection portion 73 can be connected to the head chip 30 with the connection terminals spaced apart wider than in the first connection portion 71.

In the inkjet head 5 of this embodiment, the second connection terminal row 82 extends in one direction toward the second portion 81B of the first connection terminal row 81, and the third connection terminal row 83 extends in one direction toward the first portion 81A of the first connection terminal row 81. With this configuration, even if the spacing between the connection terminals in the second connection portion 72 and the third connection portion 73 is wider than that in the first connection portion 71, the formation ranges of the second connection terminal row 82 and the third connection terminal row 83 overlap each other in one direction so that they overlap when the flexible substrate 70 is folded, so that it is not necessary to increase the width of the flexible substrate 70, and the inkjet head 5 can be made smaller.

The printer 1 according to this embodiment is equipped with the inkjet head 5 described above. This printer 1 makes it possible to provide a small, low-cost product.

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

FIG. 10 is a development view of a flexible substrate 70 according to the second embodiment.
10, in the second embodiment, a sheet-like conductive pattern 90 (so-called solid pattern) is formed in the region around the folding line L that becomes the folding portion 74 of the flexible substrate 70. The conductive pattern 90 sandwiches the folding line L and extends parallel to the X direction so as to cross the base end portion 72A.

The conductive pattern 90 makes the bending portion 74 of the flexible substrate 70 relatively easier to bend than the surrounding area. In other words, the bending portion 74 has a relatively low rigidity when bent compared to the surrounding area. The conductive pattern 90 may be electrically grounded. This allows the conductive pattern 90 to adjust the rigidity of the flexible substrate 70 as well as add electrical functions. 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. In addition, if the flexible substrate 70 has three or more conductive layers, the conductive pattern 90 may be formed on any layer other than the layer on which the signal wiring is formed.

As described above, according to the inkjet head 5 of the second embodiment having the above configuration, the bending portion 74 has a relatively low rigidity when bent compared to the surrounding area. With this configuration, the bending portion 74 is relatively easier to bend compared to the surrounding area, so that the bending position of the flexible substrate 70 can be aligned to the designed position.

In addition, in the inkjet head 5 of the second embodiment, a sheet-like conductive pattern 90 is formed in the surrounding area. With this configuration, by forming a sheet-like conductive pattern 90 in the area surrounding the bent portion 74, it is possible to make the area surrounding the bent portion 74 more difficult to bend, and to make it relatively easier to bend the flexible substrate 70 at the bent portion 74.

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 embodiment are denoted by the same reference numerals, and the description thereof will be simplified or omitted.

FIG. 11 is a development view of a flexible substrate 70 according to the third embodiment.
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.

The conductive pattern 90 makes it easier for the flexible substrate 70 to maintain its shape after bending, compared to other regions of the flexible substrate 70. In other words, by forming a conductive pattern 90 of a certain thickness in a range including the bending 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 does not undergo plastic deformation such as bending, but only bends into a U-shape), it is possible to suppress the restoration deformation of the flexible substrate 70, which has a certain degree of stiffness. 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 small radius of curvature when bent and is more easily plastically deformed than the second surface 70b.

In this way, according to the inkjet head 5 of the third embodiment configured as described above, the bent portion 74 is relatively easier to maintain its shape after bending compared to other regions of the flexible substrate 70. With this configuration, since the bent portion 74 is relatively easier to maintain its shape after bending compared 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 acting on the contact point of the second connection portion 72 can be reduced.

In addition, in the inkjet head 5 of this embodiment, a sheet-like conductive pattern 90 is formed on the folded portion 74. With this configuration, by forming the sheet-like conductive pattern 90 on the folded portion 74, the folded state of the flexible substrate 70 can be maintained, and the elastic reaction force of the base material of the flexible substrate 70 acting on the contact point of the second connection portion 72 can be reduced.

In the third embodiment, a modified example such as that shown in FIG. 12 can be adopted.

FIG. 12 is a development view of a flexible substrate 70 according to a modified example of the third embodiment.
In the conductive pattern 90 shown in FIG. 12, a gap 91 is formed extending along the folding line L of the folding portion 74. The gap 91 is formed in a slit shape extending intermittently in the X direction. According to this configuration, the gap 91 of the conductive pattern 90 makes it easier to fold the folding portion 74 along the folding line L. Therefore, the folding position of the flexible substrate 70 can be aligned to the designed position, and as a result, the workability during assembly can be improved. In addition, the intermittent portion between the gaps 91 of the conductive pattern 90 is plastically deformed, so that the folding 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. In other words, according to one modification of the third embodiment, in addition to the action and effect of the third embodiment, the action and effect of the second embodiment can be obtained.

Although preferred embodiments of the present disclosure have been described and illustrated above, it should be understood that these are illustrative of the present disclosure and should not be considered as limiting. Additions, omissions, substitutions, and other modifications can be made without departing from the scope of the present disclosure. Thus, the present disclosure should not be considered as limited by the foregoing description, but rather by the scope of the claims.

For example, in the above embodiment, an inkjet printer has been described as an example of a liquid jet recording apparatus, but the liquid jet recording apparatus is not limited to a printer. For example, a fax machine, an on-demand printer, or the like may be used.
In the above-described embodiment, a configuration in which the inkjet head moves relative to the recording medium during printing (so-called shuttle machine) has been described as an example, but the present disclosure is not limited to this configuration. The configuration according to the present disclosure may be adopted in a configuration in which the recording medium moves relative to the inkjet head while the inkjet head is fixed (so-called fixed head machine).
In the above embodiment, the recording medium P is paper, but the present invention 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 a food product.
In the above-described embodiment, the liquid ejection head is mounted on the liquid ejection recording device, but the present invention is not limited to this configuration. In other words, the liquid ejected from the liquid ejection head is not limited to the liquid that is to be landed on the recording medium, and may be, for example, a medicinal liquid to be mixed in a medicine, a food additive such as a seasoning or a fragrance to be added to food, or an aromatic to be sprayed into the air.
In the above embodiment, the configuration has been described in which the Z direction coincides with the direction of gravity, but the present invention is not limited to this configuration, and the Z direction may be aligned with the horizontal direction.
In the above embodiment, the one direction coincides with the X direction, but the present invention is not limited to this configuration. The one direction may be determined separately from the X direction.

1...Printer (liquid jet recording device)
5... Inkjet head (liquid ejection head)
30...Head tip (ejection part)
33...first actuator row 34...second actuator row 43...ejection channel 44...non-ejection channel 60...drive circuit board 63...drive circuit 64...drive terminal row 65...terminal group 70...flexible board 70a...first surface 70b...second surface 71...first connection portion 72...second connection portion 73...third connection portion 74...bent portion 81...first connection terminal row 81A...first portion 81B...second portion 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 (15)

An ejection unit that ejects liquid;
A drive circuit board that outputs a drive signal for the ejection unit;
a flexible substrate that electrically connects the drive circuit substrate and the ejection unit;
the ejection unit includes a first actuator row and a second actuator row that are driven based on the drive signal,
The flexible substrate is
A first connection portion electrically connected to the drive circuit board;
a second connection portion electrically connected to the first actuator row;
a third connection portion electrically connected to the second actuator row. the drive circuit board has a drive terminal row electrically connected to the first connection portion,
The liquid jet head according to claim 1 , wherein the drive terminal row is a group of terminals each made up of a plurality of terminals arranged at a predetermined pitch. The liquid jet head according to claim 1 or 2, characterized in that in the flexible substrate, a first distance between the first connection portion and the second connection portion is longer than a second distance between the first connection portion and the third connection portion. The liquid jet head according to claim 3, characterized in that the flexible substrate has a bent portion between the first connection portion and the second connection portion, the bent portion being bent toward the third connection portion. The liquid jet head according to claim 4, characterized in that the bent portion has a relatively low rigidity when bent compared to the surrounding area. The liquid jet head according to claim 5, characterized in that a sheet-like conductive pattern is formed in the surrounding area. The liquid jet head according to claim 4, characterized in that the bent portion is relatively easy to maintain its shape after bending compared to other areas of the flexible substrate. The liquid jet head according to claim 7, characterized in that a sheet-like conductive pattern is formed on the folded portion. The liquid jet head according to claim 8, characterized in that the conductive pattern has gaps formed therein that extend along the fold lines of the fold portions. The liquid jet head according to any one of claims 1 to 9, characterized in that in the flexible substrate, the second connection portion and the third connection portion are arranged on either side of the first connection portion. The liquid jet head according to any one of claims 1 to 10, characterized in that in the flexible substrate, the second connection portion and the third connection portion are arranged on a different surface from the first connection portion. The liquid jet head according to any one of claims 1 to 11, characterized in that the first connection portion has a first connection terminal row arranged in one direction. The first connection terminal row includes:
A first portion electrically connected to the second connection portion;
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 liquid jet head according to claim 12 , wherein the third connection portion has a third connection terminal row formed to be longer than the second portion of the first connection terminal row in the one direction. the second connection terminal row extends toward the second portion of the first connection terminal row in the one direction,
The liquid jet head according to claim 13 , wherein the third connection terminal row extends on a side of the first portion of the first connection terminal row in the one direction. A liquid jet recording device comprising the liquid jet head according to any one of claims 1 to 14.

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