Liquid discharge head and recording device

Abstract

To increase connection reliability between a discharge member and a flexible substrate.SOLUTION: A liquid discharge head includes a discharge member, a flexible substrate, and a relay substrate. The discharge member includes a plurality of nozzles for discharging a liquid, a plurality of elements for discharging the liquid from the plurality of nozzles, and a plurality of terminals electrically connected to the plurality of elements respectively. The flexible substrate includes a plurality of signal lines corresponding to the plurality of terminals. The relay substrate connects the discharge member and the flexible substrate electrically. The relay substrate includes a plurality of first pads, a plurality of second pads, and a plurality of wiring lines. The plurality of first pads are joined to the plurality of terminals of the discharge member. The plurality of second pads are joined to the plurality of signal lines of the flexible substrate. The plurality of wiring lines connect the plurality of first pads and the plurality of second pads. An area of each of the plurality of second pads is larger than an area of each of the plurality of first pads.SELECTED DRAWING: Figure 6

Description

Technical Field

[0001] The disclosed embodiments relate to a liquid ejection head and a recording apparatus.

Background Art

[0002] As printing apparatuses, inkjet printers and inkjet plotters using an inkjet recording method are known. Such an inkjet printing apparatus is equipped with a liquid ejection head for ejecting a liquid.

[0003] In such a liquid ejection head, for example, a plurality of individual electrodes provided on a liquid ejection member are each joined to a plurality of signal lines of a flexible substrate by an anisotropic conductive bonding material, whereby the ejection member and the flexible substrate are electrically connected.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, in the conventional liquid ejection head, there is still room for further improvement in terms of improving the connection reliability between the ejection member and the flexible substrate.

[0006] One aspect of the embodiment has been made in view of the above, and an object thereof is to provide a liquid ejection head and a recording apparatus capable of improving the connection reliability between the ejection member and the flexible substrate.

Means for Solving the Problems

[0007] A liquid ejection head according to an aspect of the embodiment includes an ejection member, a flexible substrate, and an intermediate substrate. The ejection member has a plurality of nozzles that eject liquid, a plurality of elements that cause the liquid to be ejected from the plurality of nozzles, and a plurality of terminals electrically connected to each of the plurality of elements. The flexible substrate has a plurality of signal lines corresponding to the plurality of terminals. The intermediate substrate electrically connects the ejection member and the flexible substrate. The intermediate substrate has a plurality of first pads, a plurality of second pads, and a plurality of wirings. The plurality of first pads are joined to the plurality of terminals of the ejection member. The plurality of second pads are joined to the plurality of signal lines of the flexible substrate. The plurality of wirings connect the plurality of first pads and the plurality of second pads. The area of each of the plurality of second pads is larger than the area of each of the plurality of first pads.

Advantages of the Invention

[0008] According to an aspect of the embodiment, the connection reliability between the ejection member and the flexible substrate can be improved.

Brief Description of the Drawings

[0009]

Figure 1

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Figure 15

DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, embodiments of the liquid discharge head and recording apparatus disclosed in the present application will be described with reference to the accompanying drawings. Note that the present disclosure is not limited to the embodiments shown below. Also, the drawings are schematic, and it should be noted that the dimensional relationships between elements, the ratios of the elements, etc. may differ from reality. Furthermore, there may be parts where the dimensional relationships and ratios between the drawings are different from each other.

[0011] Also, in the embodiments shown below, expressions such as "constant", "orthogonal", "perpendicular", or "parallel" may be used, but these expressions do not necessarily require strict "constant", "orthogonal", "perpendicular", or "parallel". That is, each of the above expressions allows for deviations such as manufacturing accuracy and installation accuracy.

[0012] In addition, each embodiment can be appropriately combined within a range that does not conflict with the processing content. Also, in the following embodiments, the same parts are denoted by the same reference numerals, and redundant explanations are omitted.

[0013] <Configuration of Printer> First, with reference to FIGS. 1 and 2, an overview of a printer 1, which is an example of a recording apparatus according to an embodiment, will be described. FIG. 1 is a front view schematically showing a schematic front of the printer 1 according to the embodiment. FIG. 2 is a plan view schematically showing a schematic plan of the printer 1 according to the embodiment. The printer 1 according to the embodiment is, for example, a color inkjet printer.

[0014] As shown in FIG. 1, the printer 1 includes a paper feed roller 2, a guide roller 3, an applicator 4, a head case 5, a plurality of transport rollers 6, a plurality of frames 7, a plurality of liquid ejection heads 8, a transport roller 9, a dryer 10, a transport roller 11, a sensor unit 12, and a recovery roller 13. The transport roller 6 is an example of a transport unit.

[0015] Furthermore, the printer 1 has a control unit 14 that controls each part of the printer 1. The control unit 14 controls the operations of the paper feed roller 2, the guide roller 3, the applicator 4, the head case 5, the plurality of transport rollers 6, the plurality of frames 7, the plurality of liquid ejection heads 8, the transport roller 9, the dryer 10, the transport roller 11, the sensor unit 12, and the recovery roller 13.

[0016] The printer 1 records an image or characters on the printing paper P by landing droplets on the printing paper P. The printing paper P is an example of a recording medium. The printing paper P is in a state of being wound around the paper feed roller 2 before use. The printer 1 transports the printing paper P from the paper feed roller 2 through the guide roller 3 and the applicator 4 into the head case 5.

[0017] The coater 4 uniformly applies the coating agent to the printing paper P. As a result, since the printing paper P can be surface-treated, the printing quality of the printer 1 can be improved.

[0018] The head case 5 houses a plurality of conveying rollers 6, a plurality of frames 7, and a plurality of liquid ejection heads 8. Inside the head case 5, a space that is isolated from the outside is formed, except for a part such as the portion where the printing paper P enters and exits, which is connected to the outside.

[0019] The internal space of the head case 5 is controlled by the control unit 14 for at least one of the control factors such as temperature, humidity, and air pressure, as necessary. The conveying roller 6 conveys the printing paper P inside the head case 5 to the vicinity of the liquid ejection head 8.

[0020] The frame 7 is a rectangular flat plate and is positioned close above the printing paper P conveyed by the conveying roller 6. Also, as shown in FIG. 2, the frame 7 is positioned such that its longitudinal direction is orthogonal to the conveying direction of the printing paper P. And inside the head case 5, a plurality (for example, four) of frames 7 are positioned at predetermined intervals along the conveying direction of the printing paper P.

[0021] The liquid ejection head 8 is supplied with liquid, for example, ink, from a liquid tank (not shown). The liquid ejection head 8 ejects the liquid supplied from the liquid tank.

[0022] The control unit 14 controls the liquid ejection head 8 based on data such as images and characters, and causes the liquid to be ejected toward the printing paper P. The distance between the liquid ejection head 8 and the printing paper P is, for example, about 0.5 to 20 mm.

[0023] The liquid ejection head 8 is fixed to the frame 7. The liquid ejection head 8 is positioned such that its longitudinal direction is orthogonal to the conveying direction of the printing paper P.

[0024] That is, the printer 1 according to the embodiment is a so-called line printer in which the liquid ejection head 8 is fixed inside the printer 1. Note that the printer 1 according to the embodiment is not limited to a line printer and may be a so-called serial printer.

[0025] A serial printer is a printer that alternately performs an operation of recording while moving the liquid ejection head 8 in a direction intersecting the conveyance direction of the printing paper P, for example, reciprocating in a substantially orthogonal direction, and the conveyance of the printing paper P.

[0026] As shown in FIG. 2, a plurality (for example, five) of liquid ejection heads 8 are fixed to one frame 7. FIG. 2 shows an example in which three liquid ejection heads 8 are located in front of the conveyance direction of the printing paper P and two liquid ejection heads 8 are located behind, and the liquid ejection heads 8 are positioned so that the centers of the respective liquid ejection heads 8 do not overlap in the conveyance direction of the printing paper P.

[0027] And a head group 8A is constituted by a plurality of liquid ejection heads 8 located on one frame 7. The four head groups 8A are located along the conveyance direction of the printing paper P. Four colors of ink are supplied to the liquid ejection heads 8 belonging to the same head group 8A. Thereby, the printer 1 can perform printing with four colors of ink using the four head groups 8A.

[0028] The colors of the ink ejected from each liquid ejection head 8 are, for example, magenta (M), yellow (Y), cyan (C), and black (K). The control unit 14 can print a color image on the printing paper P by controlling each liquid ejection head 8 to eject a plurality of colors of ink onto the printing paper P.

[0029] Note that, in order to perform surface treatment of the printing paper P, a coating agent may be ejected from the liquid ejection head 8 onto the printing paper P.

[0030] Also, the number of liquid ejection heads 8 included in one head group 8A and the number of head groups 8A mounted on the printer 1 can be appropriately changed according to the object to be printed and the printing conditions. For example, if printing within the range printable by one liquid ejection head 8, the number of liquid ejection heads 8 mounted on the printer 1 may be one.

[0031] The printing paper P that has undergone printing processing inside the head case 5 is conveyed outside the head case 5 by the conveying roller 9 and passes through the inside of the dryer 10. The dryer 10 dries the printed printing paper P. The printing paper P dried by the dryer 10 is conveyed by the conveying roller 11 and collected by the collecting roller 13.

[0032] In the printer 1, by drying the printing paper P with the dryer 10, it is possible to suppress the adhesion of the printing papers P wound up overlapping each other and the rubbing of the undried liquid at the collecting roller 13.

[0033] The sensor unit 12 is composed of a position sensor, a speed sensor, a temperature sensor, etc. The control unit 14 can judge the states of the respective parts of the printer 1 based on the information from the sensor unit 12 and control the respective parts of the printer 1.

[0034] In the printer 1 described so far, the case where the printing paper P is used as the object to be printed (i.e., the recording medium) has been shown, but the object to be printed in the printer 1 is not limited to the printing paper P, and a roll-shaped cloth or the like may be used as the object to be printed.

[0035] Also, instead of directly conveying the printing paper P, the printer 1 may place it on a conveying belt and convey it. By using the conveying belt, the printer 1 can use single-sheet paper, cut cloth, wood, tiles, etc. as the object to be printed.

[0036] Further, the printer 1 may print wiring patterns of electronic devices or the like by discharging a liquid containing conductive particles from the liquid discharge head 8. Further, the printer 1 may produce chemicals by discharging a predetermined amount of a chemical agent or a liquid containing a chemical agent from the liquid discharge head 8 toward a reaction vessel or the like.

[0037] Further, the printer 1 may include a cleaning unit for cleaning the liquid discharge head 8. The cleaning unit cleans the liquid discharge head 8 by, for example, wiping processing or capping processing.

[0038] The wiping processing is, for example, a process of removing the liquid adhering to the liquid discharge head 8 by wiping the surface of the portion where the liquid is discharged with a flexible wiper.

[0039] Further, the capping processing is carried out, for example, as follows. First, a cap is put on so as to cover the portion where the liquid is discharged, for example, the second surface 20b (see FIG. 3) of the discharge member 20 (this is called capping). Thereby, a substantially sealed space is formed between the second surface 20b and the cap.

[0040] Next, the discharge of the liquid is repeated in such a sealed space. Thereby, it is possible to remove a liquid having a higher viscosity than the standard state, foreign matters, etc. that have clogged the discharge holes (nozzles) 163 (see FIG. 4).

[0041] <Configuration of the liquid discharge head> Next, with reference to FIG. 3, the configuration of the liquid discharge head 8 according to the embodiment will be described. FIG. 3 is a side schematic view showing the internal configuration of the liquid discharge head 8 according to the embodiment. In FIG. 3, a side surface orthogonal to the longitudinal direction of the liquid discharge head 8 is shown.

[0042] The liquid ejection head 8 includes a discharge member 20, a support substrate 30, an intermediate substrate 40, a flexible substrate 50, a driving IC 60, and a liquid supply member (not shown). The discharge member 20, the support substrate 30, the intermediate substrate 40, the flexible substrate 50, the driving IC 60, and the liquid supply member are housed in a housing (not shown).

[0043] In the following description, for convenience, the direction in which the discharge member 20 is provided in the liquid ejection head 8 may be referred to as "down", and the direction in which the support substrate 30 is provided with respect to the discharge member 20 may be referred to as "up".

[0044] The discharge member 20 has a substantially flat plate shape and has a first surface 20a and a second surface 20b located on the opposite side of the first surface 20a. The first surface 20a has an opening (not shown), and liquid is supplied into the discharge member 20 through the opening from the support substrate 30.

[0045] A plurality of discharge holes 22 (see FIG. 4) for discharging liquid onto the printing paper P are located on the second surface 20b. The discharge member 20 has a flow path inside for flowing liquid from the first surface 20a to the second surface 20b.

[0046] The discharge member 20 has a plurality of displacement elements 23 (see FIG. 4). The plurality of displacement elements 23 are located on the first surface 20a of the discharge member 20.

[0047] The support substrate 30 is located on the first surface 20a of the discharge member 20. The support substrate 30 has a flow path inside and supplies the liquid supplied from the liquid supply member to the discharge member 20. Further, the support substrate 30 has a predetermined thickness thicker than the discharge member 20 and has a function of reinforcing the discharge member 20.

[0048] A liquid supply member is located on the support substrate 30. The liquid supply member is provided with openings (not shown) at both ends in the main scanning direction, which is perpendicular to the sub-scanning direction, which is the conveyance direction of the printing paper P, and parallel to the printing paper P. The liquid supply member has a flow path inside, and liquid is supplied from the outside through the openings. The liquid supply member supplies liquid to the support substrate 30. Further, the liquid supply member stores the liquid supplied to the support substrate 30.

[0049] The relay substrate 40 is located at each of two positions sandwiching the support substrate 30 on the first surface 20a of the ejection member 20. One end of the relay substrate 40 is electrically connected to the ejection member 20, and the other end of the relay substrate 40 is electrically connected to the flexible substrate 50. The relay substrate 40 has a function of relaying the signal transmitted by the flexible substrate 50 to the ejection member 20. The height of the relay substrate 40 from the first surface 20a of the ejection member 20 is lower than that of the support substrate 30. Thereby, when installing the liquid supply member on the support substrate 30, the possibility of interference between the relay substrate 40 and the liquid supply member can be reduced, so that the degree of freedom in the layout of the liquid supply member can be improved.

[0050] The flexible substrate 50 is a flexible wiring substrate, and transmits the signal sent from the outside to the relay substrate 40. One end of the flexible substrate 50 is electrically connected to the relay substrate 40, and the other end of the flexible substrate 50 is drawn out above the support substrate 30 and is electrically connected to a wiring substrate (not shown).

[0051] The drive IC 60 is mounted on the flexible substrate 50. The drive IC 60 drives each displacement element 23 in the ejection member 20 based on the drive signal sent from the control unit 14 (see FIG. 1). Thereby, the drive IC 60 can control the drive of the liquid ejection head 8.

[0052] Note that FIG. 3 shows an example of the configuration of the liquid ejection head 8, and may further include members other than the members shown in FIG. 3.

[0053] <Configuration of the ejection member and the support substrate> Next, with reference to FIG. 4, the configuration of the ejection member 20 and the support substrate 30 according to the embodiment will be described. FIG. 4 is a schematic cross-sectional view of the ejection member 20 and the support substrate 30 according to the embodiment. It is a schematic diagram showing the same.

[0054] As shown in FIG. 4, the ejection member 20 has a plurality of pressure chambers 21, a plurality of ejection holes 22, a plurality of displacement elements 23, and a plurality of terminals 24.

[0055] The plurality of pressure chambers 21 are respectively connected to a plurality of flow paths 31 in the support substrate 30. The plurality of ejection holes 22 are respectively connected to the plurality of pressure chambers 21. The plurality of displacement elements 23 are located on the first surface 20a of the ejection member 20 at a plurality of positions corresponding to the plurality of pressure chambers 21.

[0056] The plurality of terminals 24 are located on the first surface 20a of the ejection member 20 at positions sandwiching the support substrate 30. The plurality of terminals 24 are electrically connected to the plurality of displacement elements 23 respectively via electrodes and wirings (not shown). A plurality of signal lines in the flexible substrate 50 are electrically connected to the plurality of terminals 24 respectively. When a signal transmitted by the flexible substrate 50 is input from the terminal 24 to the displacement element 23, the displacement element 23 is displaced.

[0057] The support substrate 30 is located on the first surface 20a of the ejection member 20. The support substrate 30 has a plurality of spaces for accommodating the plurality of displacement elements 23 respectively on the lower surface. The support substrate 30 has a plurality of flow paths 31 inside. The plurality of flow paths 31 are respectively connected to the plurality of pressure chambers 21. The plurality of flow paths 31 open on the upper surface of the support substrate 30. Further, a liquid supply member (not shown) is located on the upper surface of the support substrate 30. The plurality of flow paths 31 are connected to the liquid supply member.

[0058] Then, liquid is supplied from the liquid supply member into the inside of the discharge member 20 through the flow path 31, and as the corresponding displacement element 23 is displaced, the pressure chamber 21 is pressed, and the liquid is discharged from the discharge hole 22. That is, the plurality of displacement elements 23 function as a plurality of elements for discharging liquid from the plurality of discharge holes 22.

[0059] As shown in FIG. 4, the discharge member 20 has a laminated structure in which a nozzle plate 20A and an actuator plate 20B are laminated. The nozzle plate 20A is provided with a plurality of discharge holes 22. The actuator plate 20B is provided with a plurality of pressure chambers 21, a plurality of displacement elements 23, and a plurality of terminals 24. When the nozzle plate 20A and the actuator plate 20B are aligned and laminated, the plurality of pressure chambers 21 and the plurality of discharge holes 22 communicate with each other to form the discharge member 20.

[0060] <Connection mode of the discharge member, relay substrate, and flexible substrate> Next, with reference to FIGS. 5 and 6, the connection mode of the discharge member 20, the relay substrate 40, and the flexible substrate 50 will be described. FIG. 5 is a side schematic view showing the configurations of the discharge member 20, the relay substrate 40, and the flexible substrate 50 according to the embodiment. FIG. 6 is a plan schematic view showing an example of the configuration of the connection portion between the relay substrate 40 and the flexible substrate 50. In FIG. 6, the lower surface of the relay substrate 40 (that is, the surface facing the discharge member 20) is shown.

[0061] As shown in FIG. 5, a plurality of terminals 24 (see FIG. 4) are located on the first surface 20a of the ejection member 20, and a plurality of signal lines 51 (see FIG. 6) corresponding to the plurality of terminals 24 are located on the surface of the flexible substrate 50. One end of the relay substrate 40 is connected to the plurality of terminals 24 of the ejection member 20, and the other end of the relay substrate 40 is connected to the plurality of signal lines 51 of the flexible substrate 50. That is, a plurality of first pads 41 (see FIG. 6) are formed at one end of the relay substrate 40, and the plurality of first pads 41 and the plurality of terminals 24 of the ejection member 20 are joined by a conductive bonding material 401. Further, a plurality of second pads 42 (see FIG. 6) are formed at the other end of the relay substrate 40, and the plurality of second pads 42 and the plurality of signal lines 51 of the flexible substrate 50 are joined by a conductive bonding material 402. The plurality of first pads 41 and the plurality of second pads 42 are respectively connected by a plurality of wirings 43. As the conductive bonding materials 401 and 402, for example, an anisotropic conductive film (ACF: Anisotropic Conductive Film) can be used.

[0062] As shown in FIG. 6, in the relay substrate 40, the area of each of the plurality of second pads 42 is larger than the area of each of the plurality of first pads 41. In this way, by increasing the area of each of the plurality of second pads 42 to be joined to the plurality of signal lines 51 of the flexible substrate 50, it is possible to suppress a connection failure between the flexible substrate 50 and the relay substrate 40. That is, when connecting the flexible substrate 50 to the relay substrate 40, a mechanical load is applied to the signal line 51 from the second pad 42 as the flexible substrate 50 bends, but by increasing the area of the second pad 42, the mechanical load on the signal line 51 can be reduced. Further, when connecting the flexible substrate 50 to the relay substrate 40, the conductive bonding material 402 is melted by heating, so thermal expansion of the flexible substrate 50 occurs and displacement of the signal line 51 from the second pad 42 is likely to occur. Even in such a case, by increasing the area of the second pad 42, even if displacement of the signal line 51 has occurred, electrical connection between the second pad 42 and the signal line 51 can be ensured. Since a connection failure between the flexible substrate 50 and the relay substrate 40 can be suppressed, the flexible substrate 50 and the discharge member 20 can be stably connected by the relay substrate 40. As a result, according to the liquid discharge head 8 according to the embodiment, the connection reliability between the discharge member 20 and the flexible substrate 50 can be improved. Note that the areas of the first pad 41 and the second pad 42 are the planar areas when the relay substrate 40 is viewed in plan.

[0063] Further, the plurality of second pads 42 are positioned such that they do not adjacent to each other in a second direction intersecting the first direction in a plurality (here, two) of regions 421 arranged along a direction from one end portion to the other end portion on the discharge member 20 side of the relay substrate 40 (hereinafter referred to as the "first direction"). Thereby, since the size of the second pad 42 along the second direction can be increased within a range where the second pads 42 do not interfere with each other, the area of the second pad 42 can be made larger.

[0064] Also, as shown in FIGS. 5 and 6, the plurality of first pads 41, the plurality of second pads 42, and the plurality of wirings 43 are located on the lower surface of the relay substrate 40 facing the discharge member 20. In this way, by positioning the plurality of first pads 41, the plurality of second pads 42, and the plurality of wirings 43 on the lower surface of the relay substrate 40 that is the same plane, the lengths of the plurality of wirings 43 can be minimized, and the electrical resistance in the relay substrate 40 can be reduced.

[0065] In FIG. 6, the case where the plurality of second pads 42 are positioned so as not to be adjacent to each other to increase the area of the second pads 42 is shown as an example. However, the structure for increasing the area of the second pads 42 in the relay substrate 40 is not limited to this. For example, as shown in FIG. 7, the area of the second pads 42 may be increased by performing pitch conversion of the plurality of wirings 43 on the relay substrate 40. FIG. 7 is a schematic plan view showing another example of the configuration of the connection portion between the relay substrate 40 and the flexible substrate 50 according to the embodiment. The plurality of wirings 43 shown in FIG. 7 are pitch-converted on the relay substrate 40. The pitch (interval) between the wirings 43 is small on the side of the plurality of first pads 41, but the pitch (interval) is large on the side of the plurality of second pads 42. Thereby, since the size of the second pads 42 along the second direction can be expanded within a range where the second pads 42 do not interfere with each other, the area of the second pads 42 can be made larger.

[0066] <Method for manufacturing a liquid ejection head> Next, a method for manufacturing the liquid ejection head 8 according to the embodiment will be described. First, a support substrate 30 is placed on the first surface 20a of the ejection member 20. Subsequently, the nozzle plate 20A and the actuator plate 20B are aligned and laminated to create a laminated structure of the ejection member 20. Subsequently, a plurality of first pads 41 of the relay substrate 40 and a plurality of terminals 24 of the ejection member 20 are joined by a conductive bonding material 401 to electrically connect the relay substrate 40 and the ejection member 20. Subsequently, a plurality of second pads 42 of the relay substrate 40 and a plurality of signal lines 51 of the flexible substrate 50 are joined by a conductive bonding material 402 to electrically connect the relay substrate 40 and the flexible substrate 50. Thereafter, a liquid supply member is placed on the support substrate 30, and members such as the ejection member 20 (and other members as necessary) are housed in a housing. Thereby, the liquid ejection head 8 according to the embodiment is obtained.

[0067] <Various Modifications> FIG. 8 is a schematic side view showing the configurations of the ejection member 20, the relay substrate 40, and the flexible substrate 50 according to Modification 1. The flexible substrate 50 shown in FIG. 8 does not mount the drive IC 60, and the drive IC 60 is located on the lower surface of the relay substrate 40 (that is, the surface facing the ejection member 20). By positioning the drive IC 60 on the lower surface of the relay substrate 40 in this way, the wiring length between the drive IC 60 and the ejection member 20 can be shortened, so that the resistance loss between the drive IC 60 and the ejection member 20 can be reduced. In addition, since the possibility of disconnection between the drive IC 60 and the ejection member 20 can be reduced, the connection reliability between the drive IC 60 and the ejection member 20 can also be improved.

[0068] Note that in FIG. 8, a heat dissipation member may be provided on the upper surface of the relay substrate 40 on the side opposite to the drive IC 60. Thereby, the heat dissipation performance of the drive IC 60 can be improved. As the heat dissipation member, a heat dissipation fin, a Peltier element, or the like may be used. Further, the drive IC 60 may be covered with a protective cover. Thereby, it is possible to suppress the liquid ejected from the ejection member 20 from adhering to the drive IC 60.

[0069] FIG. 9 is a schematic side view showing the configurations of the ejection member 20, the relay substrate 40, and the flexible substrate 50 according to Modification 2. In the relay substrate 40 shown in FIG. 9, a plurality of first pads 41 are located on the lower surface of the relay substrate 40 facing the ejection member 20. Also, a plurality of second pads 42 are located on the upper surface of the relay substrate. Further, a plurality of wirings 43 are routed to the upper and lower surfaces of the relay substrate 40 via the side surface of the relay substrate 40. In this way, by having the plurality of first pads 41 and the plurality of second pads 42 located on the lower and upper surfaces of the relay substrate 40, the ejection member 20 and the flexible substrate 50 can be electrically connected on different surfaces of the relay substrate 40. Thereby, even when the width from one end portion to the other end portion on the ejection member 20 side of the relay substrate 40 is reduced, interference between the ejection member 20 and the flexible substrate 50 is avoided, so that miniaturization of the liquid ejection head 8 can be promoted.

[0070] Note that in FIG. 9, the plurality of wirings 43 may penetrate the lower and upper surfaces of the relay substrate 40. Thereby, the length of the plurality of wirings 43 can be shortened, and the electrical resistance in the relay substrate 40 can be reduced.

[0071] FIG. 10 is a schematic side view showing the configurations of the ejection member 20, the relay substrate 40, and the flexible substrate 50 according to Modification 3. Modification 3 is different from Modification 2 in the structure of the relay substrate 40. In the relay substrate 40 shown in FIG. 10, a plurality of second pads 42 are located at positions overlapping the plurality of first pads 41 in a plan view. Thereby, the width from one end portion to the other end portion on the ejection member 20 side of the relay substrate 40 can be minimized, and miniaturization of the liquid ejection head 8 can be further promoted.

[0072] FIG. 11 is a schematic side view showing the configurations of the discharge member 20, the relay substrate 40, and the flexible substrate 50 according to Modification 4. The flexible substrate 50 shown in FIG. 11 does not have the drive IC 60 mounted thereon, and the drive IC 60 is located on the upper surface of the relay substrate 40 (that is, the surface opposite to the surface facing the discharge member 20). By positioning the drive IC 60 on the upper surface of the relay substrate 40 in this way, the drive IC 60 can be protected from the liquid discharged from the discharge member 20.

[0073] FIG. 12 is a schematic side view showing the internal configuration of the liquid discharge head 8 according to Modification 5. The structure of the relay substrate 40 of the liquid discharge head 8 shown in FIG. 12 is different from that of the liquid discharge head 8 shown in FIG. 3. As shown in FIG. 12, the relay substrate 40 and the support substrate 30 are located on the discharge member 20, and the height of the relay substrate 40 from the first surface 20a of the discharge member 20 is higher than that of the support substrate 30. In other words, the thickness of the relay substrate 40 is thicker than the thickness of the support substrate 30. By increasing the thickness of the relay substrate 40 in this way, the strength of the relay substrate 40 can be improved. Further, when installing the liquid supply member on the support substrate 30, the relay substrate 40 can be used as a buffer material for relaxing the load applied from the liquid supply member to the support substrate 30.

[0074] FIG. 13 is a schematic side view showing the internal configuration of the liquid discharge head 8 according to Modification 6. The liquid discharge head 8 shown in FIG. 13 is different from the liquid discharge head 8 shown in FIG. 3 in that the relay substrate 40 (see FIG. 6) and the support substrate 30 are integrated. In other words, the relay substrate 40 and the support substrate 30 may be formed of the same member. In the example of the liquid discharge head 8 according to Modification 6, the support substrate 30 having the function of the relay substrate 40 is located on the discharge member 20. By integrating the relay substrate 40 and the support substrate 30 in this way, the gap between the relay substrate 40 and the support substrate 30 is eliminated, and the miniaturization of the liquid discharge head 8 can be promoted.

[0075] FIG. 14 is a schematic side view showing the internal configuration of the liquid ejection head 8 according to Modification 7. The liquid ejection head 8 shown in FIG. 14 is different from the liquid ejection head 8 shown in FIG. 13 in that the drive IC 60 is located on the lower surface of the support substrate 30 (that is, the surface facing the ejection member 20). By positioning the drive IC 60 on the lower surface of the support substrate 30 in this way, the wiring length between the drive IC 60 and the ejection member 20 can be shortened, so that the resistance loss between the drive IC 60 and the ejection member 20 can be reduced. In addition, since the possibility of disconnection between the drive IC 60 and the ejection member 20 can be reduced, the connection reliability between the drive IC 60 and the ejection member 20 can also be improved.

[0076] Note that in FIG. 14, the drive IC 60 may be located on the upper surface of the support substrate 30 (that is, the surface opposite to the surface facing the ejection member 20). By positioning the drive IC 60 on the upper surface of the support substrate 30 in this way, the drive IC 60 can be protected from the liquid ejected from the ejection member 20.

[0077] Also, in FIG. 14, the drive IC 60 may be formed of a low-temperature polysilicon (LTPS) film. Thereby, the drive IC 60 can be miniaturized.

[0078] <Other Modifications> In the above-described embodiment, the example in which the relay substrate 40 is located at each of the two positions sandwiching the support substrate 30 on the first surface 20a of the ejection member 20 has been shown, but the arrangement position of the relay substrate 40 is not limited to this. For example, as shown in FIG. 15, the relay substrate 40 may be located at a position surrounding the support substrate 30 on the first surface 20a of the ejection member 20. That is, the shape of the relay substrate 40 may be a rectangular frame shape surrounding the support substrate 30 on the first surface 20a of the ejection member 20. Thereby, the strength of the relay substrate 40 can be improved. Note that FIG. 15 is a schematic plan view showing an example of the arrangement position of the relay substrate 40. In FIG. 15, a state of viewing the ejection member 20, the support substrate 30, and the relay substrate 40 from the first surface 20a side is shown.

[0079] As described above, the liquid ejection head according to the embodiment (for example, the liquid ejection head 8) includes a discharge member (for example, the discharge member 20), a flexible substrate (for example, the flexible substrate 50), and an intermediate substrate (for example, the intermediate substrate 40). The discharge member has a plurality of nozzles (for example, discharge holes 22) for discharging liquid, a plurality of elements (for example, displacement elements 23) for causing the liquid to be discharged from the plurality of nozzles, and a plurality of terminals (for example, terminals 24) electrically connected to the plurality of elements respectively. The flexible substrate has a plurality of signal lines (for example, signal lines 51) corresponding to the plurality of terminals. The intermediate substrate electrically connects the discharge member and the flexible substrate. The intermediate substrate has a plurality of first pads (for example, first pads 41), a plurality of second pads (for example, second pads 42), and a plurality of wirings (for example, wirings 43). The plurality of first pads are joined to the plurality of terminals of the discharge member. The plurality of second pads are joined to the plurality of signal lines of the flexible substrate. The plurality of wirings connect the plurality of first pads and the plurality of second pads. The area of each of the plurality of second pads is larger than the area of each of the plurality of first pads. Thus, according to the liquid ejection head according to the embodiment, the connection reliability between the discharge member and the flexible substrate can be improved.

[0080] Further, the plurality of second pads may be positioned so as not to be adjacent to each other in a second direction intersecting the first direction in a plurality of regions (for example, regions 421) arranged along a first direction from one end portion to the other end portion on the discharge member side of the intermediate substrate. Thus, according to the liquid ejection head according to the embodiment, the area of the second pads can be made larger.

[0081] Further, the intermediate substrate may have a plurality of wirings in which the interval between the wirings is large at the other end connected to the plurality of second pads rather than at one end connected to the plurality of first pads. Thus, according to the liquid ejection head according to the embodiment, the area of the second pads can be made larger.

[0082] Further, the relay substrate may have a first surface (e.g., the lower surface) facing the ejection member and a second surface (e.g., the upper surface) located on the opposite side of the first surface. The plurality of first pads, the plurality of second pads, and the plurality of wirings may be located on the first surface. Thereby, according to the liquid ejection head according to the embodiment, the lengths of the plurality of wirings can be minimized, and the electrical resistance in the relay substrate can be reduced.

[0083] Moreover, the liquid ejection head may further include a drive IC (e.g., drive IC 60) that controls the drive of the ejection member. The drive IC may be located on the first surface. Thereby, according to the liquid ejection head according to the embodiment, the resistance loss between the drive IC and the ejection member can be reduced. Also, the connection reliability between the drive IC and the ejection member can be improved.

[0084] Further, the relay substrate may have a first surface facing the ejection member, a second surface located on the opposite side of the first surface, and a side surface connecting the first surface and the second surface. The plurality of first pads may be located on the first surface. The plurality of second pads may be located on the second surface. The plurality of wirings may be routed to the first surface and the second surface via the side surface and located, or may penetrate the first surface and the second surface and be located. Thereby, according to the liquid ejection head according to the embodiment, even when the width from one end portion to the other end portion on the ejection member side of the relay substrate is reduced, interference between the ejection member and the flexible substrate is avoided, so that miniaturization of the liquid ejection head can be promoted.

[0085] Moreover, the plurality of second pads may be located at positions overlapping the plurality of first pads in a plan view. Thereby, according to the liquid ejection head according to the embodiment, the width from one end portion to the other end portion on the ejection member side of the relay substrate can be minimized, and miniaturization of the liquid ejection head can be further promoted.

[0086] Further, the liquid ejection head may further include a driving IC (for example, driving IC 60) that controls the driving of the ejection member. The driving IC may be located on the second surface. Thereby, according to the liquid ejection head according to the embodiment, the driving IC can be protected from the liquid ejected from the ejection member.

[0087] Further, the liquid ejection head may further include a support substrate (for example, support substrate 30) that is located above the ejection member and has a flow path (for example, flow path 31) through which the liquid supplied to the ejection member flows inside. Thereby, according to the liquid ejection head according to the embodiment, while reinforcing the ejection member with the support substrate, the liquid can be supplied to the ejection member.

[0088] Further, the relay substrate may be located above the ejection member. And the height of the relay substrate from the ejection member may be lower than that of the support substrate. Thereby, according to the liquid ejection head according to the embodiment, when installing the liquid supply member on the support substrate, the possibility of interference between the relay substrate and the liquid supply member can be reduced, so that the degree of freedom in the layout of the liquid supply member can be improved.

[0089] Further, the relay substrate may be located above the ejection member. And the height of the relay substrate from the ejection member may be higher than that of the support substrate. Thereby, according to the liquid ejection head according to the embodiment, the strength of the relay substrate can be improved. Also, when installing the liquid supply member on the support substrate, the relay substrate can be used as a buffer material to relieve the load applied from the liquid supply member to the support substrate.

[0090] Further, the relay substrate and the support substrate may be integrated. Thereby, according to the liquid ejection head according to the embodiment, the gap between the relay substrate and the support substrate disappears, and miniaturization of the liquid ejection head can be promoted.

[0091] Further, the support substrate may have a first surface (e.g., the lower surface) facing the ejection member and a second surface (e.g., the upper surface) located on the opposite side of the first surface. The liquid ejection head may further include a drive IC that controls the drive of the ejection member. The drive IC may be located on the first surface or the second surface. Thereby, according to the liquid ejection head according to the embodiment, the resistance loss between the drive IC and the ejection member can be reduced. Also, the connection reliability between the drive IC and the ejection member can be improved. Further, the drive IC can be protected from the liquid ejected from the ejection member.

[0092] Also, the drive IC may be formed of a low-temperature polysilicon film. Thereby, according to the liquid ejection head according to the embodiment, the drive IC can be miniaturized.

[0093] Further effects and modifications can be easily derived by those skilled in the art. Therefore, the broader aspects of the present invention are not limited to the specific details and representative embodiments represented and described as above. Accordingly, various changes can be made without departing from the spirit or scope of the general inventive concept defined by the appended claims and their equivalents.

Description of Reference Numerals

[0094] 1 Printer 8 Liquid ejection head 14 Control unit 20 Ejection member 21 Pressure chamber 22 Ejection hole 23 Displacement element 24 Terminal 30 Support substrate 31 Flow path 40 Relay substrate 41 First pad 42 Second pad 43 Wiring 50 Flexible substrate 51 Signal line 60 Drive IC 421 Region

Claims

1. An ejection member having an ejection hole and an element for ejecting liquid from the ejection hole; a first wiring board electrically connected to the discharge member; a second wiring board electrically connected to the first wiring board; Equipped with The first wiring substrate is A first connection portion connected to the discharge member; a second connection portion connected to the second wiring board; A wiring that connects the first connection portion and the second connection portion; It has The first connection portion and the second connection portion are located on the same surface of the first wiring substrate. Liquid ejection head.

2. A discharge member having a discharge hole and an element for discharging liquid from the discharge hole; a first wiring board electrically connected to the discharge member; a second wiring board electrically connected to the first wiring board; Equipped with The first wiring substrate is A first connection portion connected to the discharge member; a second connection portion connected to the second wiring board; A wiring that connects the first connection portion and the second connection portion; It has The first connection portion does not overlap the element in a plan view. Liquid ejection head.

3. The first wiring substrate does not overlap with the element when viewed in a plan view. The liquid ejection head according to claim 2 .

4. The discharge member has a first end region and a second end region; the element is located between the first end region and the second end region in a plan view, The first connection portion is connected to the first end region. The liquid ejection head according to claim 2 .

5. The first connection portion has a plurality of first pads, The second connection portion has a plurality of second pads, An area of ​​any one of the second pads is larger than an area of ​​any one of the first pads.

3. The liquid ejection head according to claim 1.

6. Further comprising an electronic component mounted on the second wiring board, the discharge member further has a discharge surface having the discharge hole, The height of the electronic component from the ejection surface is greater than the height of the first wiring substrate from the ejection surface.

3. The liquid ejection head according to claim 1.

7. Further comprising an electronic component mounted on the second wiring board, The electronic component is located between the second wiring board and the ejection member in a plan view.

3. The liquid ejection head according to claim 1.

8. The electronic component overlaps the first wiring board when viewed in a plan view.

8. A liquid ejection head according to claim 7.

9. Further comprising an electronic component mounted on the second wiring board, The electronic component is mounted on one of the two surfaces of the second wiring board that is connected to the first wiring board.

3. The liquid ejection head according to claim 1.

10. The electronic component does not overlap the discharge member when viewed in a plan view. The liquid ejection head according to claim 9.

11. The first connection portion has a plurality of first pads, The second connection portion has a plurality of second pads, The second pads are arranged in a plurality of regions aligned along a first direction from one end of the first wiring substrate on the discharge member side to the other end of the first wiring substrate so as not to be adjacent to each other in a second direction intersecting the first direction.

3. The liquid ejection head according to claim 1.

12. The first connection portion has a plurality of first pads, The second connection portion has a plurality of second pads, the wiring includes a plurality of wirings connecting the plurality of first pads and the plurality of second pads; In the first wiring board, the intervals between the wires connected to the second pads are larger than the intervals between the wires connected to the first pads.

3. The liquid ejection head according to claim 1.

13. The present invention further comprises a support substrate positioned on the discharge member and having a flow path therein through which the liquid supplied to the discharge member flows.

3. The liquid ejection head according to claim 1.

14. Further comprising an electronic component mounted on the second wiring board, the discharge member further has a discharge surface having the discharge hole, The height of the electronic component from the ejection surface is greater than the height of the support substrate from the ejection surface. The liquid ejection head according to claim 13.

15. A recording device equipped with a liquid ejection head according to claim 1 or 2.

Images