Liquid discharge head and method for manufacturing liquid discharge head

Abstract

The present application relates to a liquid ejection head and a manufacturing method of a liquid ejection head, and provides a liquid ejection head with high mountability. A liquid ejection head according to one embodiment includes an actuator section having a plurality of actuator elements at least a portion of which is divided by a plurality of grooves and in which an electrode layer is formed on one face; and a wiring substrate having a plurality of wiring electrodes mounted to the one face of the actuator section via a solder layer, at least a portion of which is divided by the grooves, and which are arranged opposite to the plurality of actuator elements.

Description

Technical Field

[0001] The embodiments of the present invention relate to a liquid ejector head and a method for manufacturing a liquid ejector head. Background Technology

[0002] In liquid ejector heads used in inkjet printers, actuator components utilizing piezoelectric materials such as PZT are used as the driving source. Within these actuator components, actuator elements (driving elements) are arranged at very narrow intervals, and the wiring used for driving is also miniaturized. For example, to handle wiring with a narrow pitch of approximately 100 μm, a flexible wiring substrate (hereinafter referred to as FPC) is sometimes directly soldered to the electrodes of the actuator component.

[0003] Such actuators are fragile due to the tiny shape of their actuator components, making it difficult to ensure installation.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Application Publication No. 2011-56730 Summary of the Invention

[0007] The technical problem that the invention aims to solve

[0008] The problem to be solved by the present invention is to provide a liquid nozzle that can improve installability.

[0009] Technical solutions for solving the problem

[0010] One embodiment of the liquid ejector head includes: an actuator component, at least a portion of which is divided by a plurality of slots, having a plurality of actuator elements having an electrode layer formed on one side; and a wiring substrate, mounted on one side of the actuator component via a solder layer, at least a portion of which is divided by the slots, having a plurality of wiring electrodes disposed opposite to the plurality of actuator elements.

[0011] The method for manufacturing a liquid ejector head according to the embodiments involves mounting a substrate with wiring on a piezoelectric component having an electrode layer via a solder layer. After mounting the wiring substrate, a portion of the stack is divided by forming a plurality of grooves on the stack of the piezoelectric component, the electrode layer, the solder layer and the wiring substrate. Attached Figure Description

[0012] Figure 1 This is a cross-sectional view showing a portion of the structure of the liquid ejector head according to the first embodiment.

[0013] Figure 2 This is a cross-sectional view showing a portion of the structure of the liquid ejector head.

[0014] Figure 3 This is an explanatory diagram showing the manufacturing method of the liquid nozzle.

[0015] Figure 4 This is an explanatory diagram showing the structure and manufacturing method of the actuator component in the liquid ejector head.

[0016] Figure 5 This is an explanatory diagram showing the structure and manufacturing method of the FPC in the liquid nozzle.

[0017] Explanation of reference numerals in the attached figures

[0018] 1…Liquid nozzle, 10…Base component, 20…Actuator component, 21…Drive piezoelectric element, 22…Non-drive piezoelectric element, 23…Gate, 25…Electrode removal section, 26…Connection section, 30…Vibrating plate, 31…Pressure chamber, 32…Common chamber, 33…Connecting section, 40…Flow path component, 41…Guide wall section, 42…Partition wall section, 50…Nozzle plate, 51…Nozzle, 60…Frame section, 70…Drive circuit, 71a…Gate, 71b…Mounting parts, 72…Base film, 73…Wiring layer, 74…Solder plating (solder layer), 75…Adhesive 76…Insulating cover layer, 100…Liquid ejection device, 116…Control unit, 200…Layer, 201…Layered piezoelectric component, 211…Piezoelectric layer, 212…Dummy layer, 221…Internal electrode, 222…Internal electrode, 223…External electrode, 224…External electrode, 301…Vibration area, 302…Support area, 405…Flow path substrate, 721…Base component, 731…Wireline electrode, 741…Mounting part, 1161…Control circuit, 2230…Electrode layer, 2240…Electrode layer, 77…Driver IC. Detailed Implementation

[0019] The following is for reference Figures 1 to 5 The liquid ejector head 1 according to the first embodiment will be described. Figure 1 and Figure 2 This is a cross-sectional view showing a portion of the structure of the liquid ejector head 1. Figures 3 to 5 This is an explanatory diagram of the manufacturing method of the liquid ejector head 1. Figure 4 This describes the structure and manufacturing method of the actuator component 20. Figure 5 This diagram illustrates the structure and manufacturing method of the FPC71. Arrows X, Y, and Z in the diagram represent three mutually orthogonal directions. For ease of explanation, some structures have been enlarged, reduced, or omitted in the diagrams.

[0020] like Figure 1 and Figure 2As shown, the liquid ejector head 1 includes a base component 10, a pair of actuator components 20, a flow path component 40, a nozzle plate 50 having multiple nozzles 51, a frame component 60 as a structural component, and a drive circuit 70. The liquid ejector head 1 is an inkjet head installed in a liquid ejection device 100 such as an inkjet recording device.

[0021] As an example, the liquid ejector head 1 includes two actuator components 20 that are piezoelectric components, and each has two rows of nozzles 51 arranged in the column direction (X direction), a row of pressure chambers 31 arranged in the column direction, and a row of piezoelectric elements 21, 22 (actuator elements) arranged in the column direction. In this embodiment, an example is shown where the stacking direction of the multiple piezoelectric layers 211, the vibration direction of the piezoelectric elements 21, and the vibration direction of the vibrating plate 30 are all along the Z direction.

[0022] The base component 10 supports a pair of actuator components 20. The base component 10 is configured as a plate, for example. The base component 10 may also be a circuit board.

[0023] Actuator components 20 are disposed on one side of base component 10. For example, two actuator components 20 are arranged in the Y direction.

[0024] The actuator component 20 includes: a plurality of driven piezoelectric elements 21 and a plurality of non-driven piezoelectric elements 22, which are alternately arranged along a column direction to form an actuator; and a connecting portion 26 that integrally connects the plurality of piezoelectric elements 21, 22 on the base component 10 side. The actuator component 20 is a stacked piezoelectric component 201 (stacked piezoelectric) having a plurality of piezoelectric body layers 211 and a plurality of internal electrodes 221, 222.

[0025] In the actuator component 20, a plurality of driven piezoelectric elements 21 and a plurality of non-driven piezoelectric elements 22 are arranged at certain intervals in one direction.

[0026] As an example, the multiple driven piezoelectric elements 21 and the multiple non-driven piezoelectric elements 22 are all configured as cuboid columns with the same external shape. The actuator component 20 is divided into multiple driven piezoelectric elements 21 and non-driven piezoelectric elements 22 at one end by forming multiple slots 23 from one side. The multiple driven piezoelectric elements 21 and non-driven piezoelectric elements 22 are arranged in the column direction with the same spacing through slots 23 of the same width. In addition, the depth of the slots 23 of the actuator component 20 is set to be smaller than the total length of the actuator component 20 in the Z direction, so a connecting portion 26 is formed on the side of the bottom surface of the slot 23 near the base component 10, which integrally connects the multiple elements 21 and 22.

[0027] The connecting portion 26 is disposed on the base end side of the plurality of piezoelectric elements 21, 22, and is a block-shaped component that connects the plurality of piezoelectric elements 21, 22. That is, the connecting portion 26 is configured as a plate with its long side direction along the X direction and connected to the entire long side direction of the stacked piezoelectric component 201.

[0028] On one side of the actuator component 20, in the Y direction (different from the Z direction), a plurality of external electrodes 223, each serving as an individual electrode, are formed. These external electrodes 223 are separated from each other, for example, by grooves 23 formed on one side of the actuator component 20 via an electrode layer 2230, thus forming a plurality of separate individual electrodes. In other words, a plurality of separate individual electrodes are constituted by the electrode layer 2230 formed on one side of the actuator component 20. On one side of the actuator component 20, the FPC 71 is electrically and mechanically connected to the external electrodes 223, which serve as individual electrodes, via solder mounting.

[0029] Additionally, a common electrode constituting the external electrode 224 is formed on the other side of the actuator component 20 in the Y direction. The common electrode is formed by an electrode layer 2240 that is formed on the entire other side of the actuator component 20.

[0030] For example, multiple driven piezoelectric elements 21 and multiple non-driven piezoelectric elements 22 are respectively configured as rectangles in which the short side direction is along the column direction of the element column and the long side direction is along the extension direction orthogonal to the column direction and the Z direction when viewed from the Z direction.

[0031] The drive piezoelectric elements 21 are arranged in the Z direction at positions opposite to the plurality of pressure chambers 31 formed in the flow path component 40. As an example, the center positions of the drive piezoelectric elements 21 in the column direction and the extension direction are arranged side by side in the Z direction with the center positions of the pressure chambers 31 in the column direction and the extension direction.

[0032] The non-driven piezoelectric elements 22 are arranged in the Z direction at positions opposite to the plurality of partition portions 42 formed on the flow path member 40. As an example, the center positions of the non-driven piezoelectric elements 22 in the column direction and the extension direction are arranged side by side with the center positions of the partition portions 42 in the column direction and the extension direction in the Z direction.

[0033] For example, actuator component 20 forms grooves 23 by cutting a stacked piezoelectric component 201 pre-bonded to base component 10 from an end face opposite to the base component 10 side, thereby forming a plurality of piezoelectric elements in rectangular columnar shapes at predetermined intervals. Furthermore, electrode layers are formed on the formed plurality of columnar elements, thereby forming a plurality of alternately arranged driven piezoelectric elements 21 and a plurality of non-driven piezoelectric elements 22. The plurality of driven piezoelectric elements 21 and the plurality of non-driven piezoelectric elements 22 are alternately arranged side-by-side in the column direction, separated by grooves 23.

[0034] For example, the stacked piezoelectric component 201 constituting the actuator component 20 is formed by stacking and sintering sheet-like piezoelectric materials.

[0035] The piezoelectric components constituting the driven piezoelectric element 21 and the non-driven piezoelectric element 22 are, for example, stacked piezoelectric components 201. The driven piezoelectric element 21 and the non-driven piezoelectric element 22 each have multiple stacked piezoelectric layers 211 and internal electrodes 221, 222 formed on the main surface of each piezoelectric layer 211. Furthermore, as an example, the driven piezoelectric element 21 and the non-driven piezoelectric element 22 have the same stacked structure. Moreover, the driven piezoelectric element 21 and the non-driven piezoelectric element 22 each have external electrodes 223, 224 formed on their surfaces.

[0036] The piezoelectric layer 211 is formed into a thin plate shape, for example, from a PZT (lead zirconate titanate) based material or a lead-free KNN (sodium potassium niobate) based material. Multiple piezoelectric layers 211 are stacked with their thickness direction along the stacking direction and bonded together. For example, in this embodiment, the thickness direction and stacking direction of the piezoelectric layers 211 are arranged along the vibration direction (Z direction).

[0037] Internal electrodes 221 and 222 are conductive films of a predetermined shape made of a sinterable conductive material such as silver or palladium. Internal electrodes 221 and 222 are formed in predetermined areas on the main surface of each piezoelectric layer 211. Internal electrodes 221 and 222 are mutually distinct electrodes. For example, one internal electrode 221 is formed in the extension direction (Y direction), which is orthogonal to the arrangement direction (X direction) and vibration direction (Z direction) of the plurality of driven piezoelectric elements 21 and the plurality of non-driven piezoelectric elements 22, reaching one end of the piezoelectric layer 211 but not the other end. Another internal electrode 222 is formed in the extension direction, reaching one end of the piezoelectric layer 211 but not the other end. Internal electrodes 221 and 222 are respectively connected to external electrodes 223 and 224 formed on the sides of the piezoelectric elements 21 and 22.

[0038] In addition, the stacked piezoelectric component 201 constituting the driving piezoelectric element 21 and the non-driving piezoelectric element 22 also has a dummy layer 212 at either or both of the ends on the base component 10 side and the nozzle plate 50 side.

[0039] External electrodes 223 and 224 are formed on the surfaces of the plurality of driven piezoelectric elements 21 and the plurality of non-driven piezoelectric elements 22, and are configured by converging the ends of the internal electrodes 221 and 222. For example, external electrode 223 is formed on one end face in the extension direction of piezoelectric layer 211. External electrode 224 is formed on the other end face in the extension direction of piezoelectric layer 211.

[0040] External electrodes 223 and 224 are formed into films of Ni, Cr, Au, etc., using known methods such as plating and sputtering. External electrodes 223 and 224 are different electrodes. External electrodes 223 and 224 are respectively disposed on different side portions of multiple driven piezoelectric elements 21 and multiple non-driven piezoelectric elements 22.

[0041] In this embodiment, as an example, the external electrode 223 is a separate electrode, and the external electrode 224 is a shared electrode. The external electrode 223, which serves as the separate electrode for the plurality of driven piezoelectric elements 21 and the plurality of non-driven piezoelectric elements 22, is formed during the formation of the groove 23 in the manufacturing process, so that the electrode layer 2230 formed on one side of the stacked piezoelectric component 201 is arranged independently of each other. Furthermore, the electrode layer 2230 forming the external electrode 223 is formed on one side of the actuator component 20 in a predetermined area above the bottom of the groove 23. That is, a portion of one side of the actuator component 20 on the base side has an electrode removal portion 25 where the electrode layer 2230 is removed or not formed. Additionally, the electrode layer 2240 is formed on the other side of the actuator component 20, reaching a position below the bottom of the groove 23.

[0042] External electrodes 223 are connected to the drive circuit 70 via a flexible substrate FPC 71, which serves as an example of a wiring substrate, on the side of the actuator component 20. For example, each external electrode 223 is connected to the wiring layer 73 of the FPC 71 and connected to the control unit 116, which serves as the drive unit, via the drive IC 77 of the drive circuit 70, thus enabling drive control via the control circuit 1161. Furthermore, external electrodes 224 may also be wound around the side of the external electrodes 223 and connected to the drive circuit 70 via the FPC 71.

[0043] like Figure 1 and Figure 3 As shown, the external electrode 224 formed on the end face of the other side of the actuator component 20 is configured such that the groove 23 is shallower than the end of the electrode layer 2240 on the base component 10 side, so that in the region near the bottom of the groove 23 on the base component 10 side, the electrode layer 2240 is continuous on the other side of the stacked piezoelectric component 201, forming a common electrode. The external electrode 224 is grounded, for example.

[0044] The dummy layer 212 is made of the same material as the piezoelectric layer 211. Since the dummy layer 212 has an electrode on only one side and no electric field is applied, it does not deform. That is, the dummy layer 212 does not function as a piezoelectric element, but serves as a substrate during fixing or as a polishing allowance for polishing to achieve accuracy during or after assembly.

[0045] For example, the side of the actuator component 20 where the individual electrodes are arranged can also be formed by chamfering or cutting a portion of the base component 10 side into a stepped shape, thereby creating a recessed portion on the base component 10 side that recedes away from the FPC71. The recessed portion is provided, for example, in the dummy layer 212. That is, a portion of the actuator component 20 that does not function as a piezoelectric element and does not deform is removed. As an example, the electrode removal portion 25 that removes a portion of the electrode layer 2230 can also be formed by the recessed portion.

[0046] In addition, the vibration direction of each piezoelectric element 21 and 22 is along the stacking direction, and by applying an electric field, they are displaced in the d33 direction.

[0047] As an example, each piezoelectric element 21 and 22 is set to have 3 or more layers and less than 50 layers, the thickness of each layer is set to be more than 10 μm and less than 40 μm, and the product of the thickness and the total number of layers is set to be less than 1000 μm.

[0048] The piezoelectric element 21 is driven to vibrate by applying voltage to the internal electrodes 221 and 222 via external electrodes 223 and 224. In this embodiment, the piezoelectric element 21 is driven to vibrate longitudinally along the stacking direction of the piezoelectric layer 211. The longitudinal vibration described herein is, for example, "vibration in the thickness direction as defined by the piezoelectric constant d33". The longitudinal vibration of the piezoelectric element 21 displaces the vibrating plate 30, thereby deforming the pressure chamber 31.

[0049] The flow path component 40 includes a vibrating plate 30 disposed opposite to one side of the actuator component 20 in the deformation direction and a flow path substrate 405 stacked on one side of the vibrating plate 30.

[0050] The vibrating plate 30 is disposed between the flow path substrate 405 and the actuator component 20 in the vibration direction. The vibrating plate 30 and the flow path substrate 405 together constitute the flow path component 40. The vibrating plate 30 extends in a direction that intersects with the side of the stacked piezoelectric component 201 where individual electrodes and shared electrodes are formed.

[0051] The vibrating plate 30 extends along a surface orthogonal to the Z-direction, which is the vibration direction, and engages with the surface on one side of the piezoelectric layer 211 of the plurality of piezoelectric elements 21, 22, i.e., the nozzle plate 50 side, in the vibration direction. The vibrating plate 30 is configured to be deformable, for example. The vibrating plate 30 engages with the driving piezoelectric element 21 and the non-driving piezoelectric element 22 of the actuator component 20 and the frame portion 60. For example, the vibrating plate 30 has a vibration region 301 opposite to the piezoelectric elements 21, 22 and a support region 302 opposite to the frame portion 60.

[0052] The vibration region 301 is, for example, a flat plate arranged such that its thickness direction corresponds to the vibration direction of the piezoelectric layer 211. The surface direction of the vibration plate 30 extends in the arrangement direction of the plurality of driven piezoelectric elements 21 and the plurality of non-driven piezoelectric elements 22. The vibration plate 30 is, for example, a metal plate. The vibration plate 30 has a plurality of vibration portions opposite to each pressure chamber 31 and capable of individual displacement. The vibration plate 30 is formed by integrally connecting the plurality of vibration portions.

[0053] As an example, the vibrating plate 30 is made of nickel or SUS plate, with a thickness of approximately 5 μm to 15 μm along the vibration direction. Furthermore, the vibration region 301 may have creases or steps formed in areas adjacent to or between adjacent vibration locations to facilitate displacement of multiple vibration locations. The vibration region 301 deforms by displacing the area opposite to the driving piezoelectric element 21 through the elongation and compression of the driving piezoelectric element 21. For example, since the vibrating plate 30 requires a very thin and complex shape, it is formed using electroforming or similar methods. The vibrating plate 30 is bonded to the upper surface of the actuator component 20 by bonding or the like.

[0054] The support region 302 is a plate-shaped component disposed between the frame portion 60 and the flow path substrate 405. The support region 302 has a connecting portion 33, which has a through hole communicating with the common chamber 32.

[0055] For example, the connecting portion 33 has a filter component that has multiple fine holes that allow liquid to pass through, serving as a through hole.

[0056] The flow path substrate 405 is disposed between the nozzle plate 50 and the vibrating plate 30 in the vibration direction. The flow path substrate 405 is joined to one side of the vibrating plate 30 in the vibration direction.

[0057] The flow path substrate 405 has wall components such as guide wall portion 41 and partition wall portion 42, forming a defined ink flow path having multiple pressure chambers 31 that are separated from each other and multiple separate flow paths that connect the pressure chambers 31 to the common chamber 32.

[0058] Within the flow path substrate 405, multiple pressure chambers 31 are separated by partition walls 42. That is, the two sides of the pressure chambers 31 in the parallel direction are formed by partition walls 42. Each pressure chamber 31 communicates with a nozzle 51 formed on a nozzle plate 50 disposed on one side. In addition, the side of the pressure chamber 31 opposite to the nozzle plate 50 is blocked by a vibrating plate 30.

[0059] Multiple pressure chambers 31 are spaces formed on one side of the vibration area 301 of the vibrating plate 30, and are connected to a common chamber 32 via individual flow paths and connecting portions 33. The multiple pressure chambers 31 are connected to nozzles 51 formed on the nozzle plate 50. In addition, the side of the pressure chambers 31 opposite to the nozzle plate 50 is blocked by the vibrating plate 30.

[0060] Multiple pressure chambers 31 contain liquid supplied from a common chamber 32, which is deformed by the vibration of a vibrating plate 30 that forms part of the pressure chamber 31, thereby ejecting the liquid from the nozzle 51.

[0061] The partition wall 42 is a wall member that separates the multiple pressure chambers 31 arranged in a parallel direction and forms the two sides of the pressure chambers 31. The partition wall 42 is disposed opposite to the non-driven piezoelectric element 22 across the vibrating plate 30 and is supported by the non-driven piezoelectric element 22. Multiple partition wall sections 42 are provided at a spacing that is the same as the spacing between the multiple pressure chambers 31.

[0062] The nozzle plate 50 is configured, for example, as a square plate with a thickness of about 10 μm to 100 μm, made of a metal such as SUS / Ni or a resin material such as polyimide. The nozzle plate 50 is disposed on one side of the flow path substrate 405 such that it covers the opening on one side of the pressure chamber 31.

[0063] Multiple nozzles 51 are arranged in a first direction, which is the same as the arrangement direction of the pressure chambers 31, forming a nozzle array. For example, two rows of nozzles 51 are provided, with each nozzle 51 positioned at a position corresponding to the multiple pressure chambers 31 arranged in the two rows. In this embodiment, the nozzles 51 are respectively positioned at the ends of the pressure chambers 31 in the extending direction.

[0064] The frame portion 60 is a structure that is joined to the vibrating plate 30 together with the piezoelectric elements 21 and 22. The frame portion 60 is disposed on the side of the piezoelectric elements 21 and 22 and the vibrating plate 30 opposite to the flow path substrate 405; for example, in this embodiment, it is disposed adjacent to the actuator component 20. The frame portion 60 forms the outline of the liquid ejector head 1. Alternatively, the frame portion 60 may also have a liquid flow path formed internally. In this embodiment, the frame portion 60 is joined to the other side of the vibrating plate 30, and a common chamber 32 is formed between it and the vibrating plate 30.

[0065] The common chamber 32 is formed inside the frame portion 60 and is connected to the pressure chamber 31 through the connecting portion 33 provided in the vibrating plate 30 and a separate flow path.

[0066] The drive circuit 70 includes an FPC71 (Flexible printed circuit board) connected to the actuator component 20 via various wiring, a drive IC77 mounted on the FPC71, and a printed wiring board mounted on the other end of the FPC71.

[0067] The drive circuit 70 applies a drive voltage to the external electrodes 223 and 224 through the drive IC 77, thereby driving the drive piezoelectric element 21, causing the volume of the pressure chamber 31 to increase or decrease, and thus ejecting droplets from the nozzle 51.

[0068] likeFigure 1 and Figure 5 As shown, the FPC71, which serves as a wiring substrate, is connected to the side of the actuator component 20. The FPC71 is mounted on one side of the actuator component 20 via a solder coating 74.

[0069] At one end of the FPC71, a plurality of grooves 71a are formed that are continuous with the grooves 23 of the actuator component 20. Here, for example, one end of the FPC71 in a first direction becomes a bonding region, i.e., a first region R1, and the other end becomes a non-bonding region, i.e., a second region R2. The FPC71 is divided by a plurality of grooves 71a by being part of the bonding region, thereby being arranged opposite to a plurality of piezoelectric elements 21, 22, forming a plurality of mounting parts 71b that are bonded to external electrodes 223, which are a plurality of individual electrodes. As the FPC71, a COF (Chip on Film) is used, on which a driver IC 77, which is an electronic component, is mounted.

[0070] The FPC71 is composed of a laminate comprising a base film 72 (base layer), a wiring layer 73 having multiple wiring electrodes 731, a solder plating film 74 (solder layer) having multiple solder mounting portions 741, an adhesive layer 75, and an insulating cover layer 76, and a driver IC 77 is mounted thereon. Furthermore, in Figure 5 For illustrative purposes, the adhesive layer 75 and the insulating covering layer 76 are omitted.

[0071] The base film 72 is mainly composed of polyimide in the form of a sheet of a specified thickness. The base film 72 is divided by a groove 71a on one end side, thereby having a plurality of base parts 721 arranged separately in a comb-like pattern on one end side.

[0072] The wiring layer 73 is made of a conductive material such as metal and is formed on the surface of the base film 72 in a predetermined pattern. The wiring layer 73 is, for example, formed of copper foil. The wiring layer 73 has a plurality of wiring electrodes 731 patterned as lines. For example, the wiring electrodes 731 are formed corresponding to positions between the slots 71a. Furthermore, the wiring electrodes 731 are configured to be narrower than the width of the mounting part 71b. That is, each wiring electrode 731 is a linear wiring layer narrower than the solder mounting portion 741.

[0073] A solder coating 74 is formed at one end of the first region R1 of the FPC 71 and is bonded to the piezoelectric elements 21 and 22. The solder coating 74 has a plurality of solder mounting portions 741 arranged separately from each other by grooves 71a. That is, the solder mounting portions 741 are formed on the portions of each wiring electrode 731 of the wiring layer 73 that are separated by the grooves 71a. The solder mounting portions 741 have the same spacing and width as each element 21 and 22. That is, the width of each solder mounting portion 741 is configured to be wider than that of each wiring electrode 731. Furthermore, the solder coating 74 is configured to have a thickness of approximately 3 to 10 μm.

[0074] The adhesive layer 75 and the insulating cover layer 76 are formed in a second region R2 of the base film 72, other than the bonding region on the surface where the wiring layer 73 is formed. That is, the insulating cover layer 76 is formed on the base film 72 where a plurality of wiring electrodes 731 are formed, with the adhesive layer 75 in between.

[0075] In this embodiment, the FPC71 has a plurality of slots 71a formed on one end of the first region R1. By dividing one end into a plurality of slots, it has a plurality of mounting parts 71b that are respectively connected to each piezoelectric element 21, 22. For example, when the FPC71 is engaged with the actuator component 20, when the slot 23 of the actuator component 20 is formed, the slots 71a are also formed on the FPC71 at the same time. Thus, at least a portion of the FPC71 is divided by the slots 71a, forming a plurality of mounting parts 71b that are arranged opposite to the plurality of piezoelectric elements 21, 22 and each have a wiring electrode 731.

[0076] The driver IC77 is connected to external electrodes 223 and 224 via FPC71. The driver IC77 is an electronic component used for ejection control.

[0077] The driver IC 77 generates control signals and drive signals for operating each drive piezoelectric element 21. Based on the image signal input from the control unit 116 of the liquid ejection device 100 equipped with the liquid ejection head 1, the driver IC 77 generates control signals for controlling the timing of ink ejection and selecting the drive piezoelectric elements 21 for ink ejection. Additionally, based on the control signals from the control unit 116, the driver IC 77 generates a voltage, i.e., a drive signal, applied to the drive piezoelectric element 21. When the driver IC 77 applies the drive signal to the drive piezoelectric element 21, the drive piezoelectric element 21 is driven to change the volume of the pressure chamber 31 by displacing the vibrating plate 30. This causes pressure vibration in the ink filling the pressure chamber 31. Through this pressure vibration, the ink is ejected from the nozzle 51, which communicates with the pressure chamber 31. Furthermore, the liquid ejection head 1 can also achieve grayscale representation by changing the amount of ink droplets falling on one pixel. Alternatively, the liquid ejection head 1 can be configured to change the amount of ink droplets falling on one pixel by changing the number of ink ejections. Thus, the driver IC77 is an example of applying a drive signal to the application portion of the drive piezoelectric element 21.

[0078] For example, the driver IC77 includes a data buffer, a decoder, and a driver. The data buffer stores print data in a time sequence for each driven piezoelectric element 21. The decoder controls the driver for each driven piezoelectric element 21 based on the print data stored in the data buffer. Based on the decoder's control, the driver outputs a drive signal that actuates each driven piezoelectric element 21. The drive signal is, for example, a voltage applied to each driven piezoelectric element 21.

[0079] The printed wiring board (PWA) is a PWA that houses various electronic components and connectors and has a head control circuit. The PWA is connected to the control unit 116 of the liquid ejection device 100.

[0080] In the liquid ejector head 1 configured as described above, an ink flow path is formed by the nozzle plate 50, the frame portion 60, the flow path substrate 405, and the vibrating plate 30, having a plurality of pressure chambers 31 communicating with the nozzle 51 and a common chamber 32 communicating with each of the plurality of pressure chambers 31. For example, the common chamber 32 communicates with the ink cartridge, and ink is supplied to each pressure chamber 31 through the common chamber 32. All the driving piezoelectric elements 21 are connected by wiring in a manner that allows voltage to be applied. In the liquid ejector head 1, for example, when the control unit 116 applies a driving voltage to the electrodes 221, 222 via the driving IC 77, the driving piezoelectric element 21 of the driven object vibrates, for example, in the stacking direction, that is, in the thickness direction of each piezoelectric layer 211. That is, the driving piezoelectric element 21 vibrates longitudinally.

[0081] Specifically, the control unit 116 applies a driving voltage to the internal electrodes 221 and 222 of the driving piezoelectric element 21 of the driven object, thereby selectively driving the driving piezoelectric element 21 of the driven object. Moreover, by combining the deformation in the tensile direction and the deformation in the compression direction caused by the driving piezoelectric element 21 of the driven object, the vibrating plate 30 is deformed, the volume of the pressure chamber 31 changes, thereby guiding the liquid from the common chamber 32 and causing it to be ejected from the nozzle 51.

[0082] Reference Figures 3 to 5 An example of a method for manufacturing the liquid ejector head 1 according to this embodiment will be described. First, internal electrodes 221 and 222 are formed on a piezoelectric material formed into a sheet by a printing process. Then, multiple piezoelectric layers 211 having internal electrodes 221 and 222 are stacked, and a firing process and a polarization process are performed to form a stacked piezoelectric component 201.

[0083] Then, the piezoelectric element 21 of the stacked piezoelectric component 201 with internal electrodes 221 and 222 pre-formed is polarized and attached to the base component 10 using an adhesive or the like. For example, in the case of two actuator components 20, the stacked piezoelectric component 201, which is integrally formed, can be joined to the base component 10 and then divided into two by groove processing or the like, or two stacked piezoelectric components 201 constituting the two actuator components 20 can be prepared separately.

[0084] Then, with the stacked piezoelectric component 201 disposed on the base component 10, the surfaces of the base component 10 and the stacked piezoelectric component 201 are surface-machined using tools such as a diamond cutter, thereby shaping the outer surface of the stacked piezoelectric component 201. This ensures the flatness of the upper surface of the actuator component 20 that is joined to the vibrating plate 30 in subsequent processes.

[0085] Next, electrode layers 2230 and 2240, which become external electrodes 223 and 224, are formed on one and the other end faces of the stacked piezoelectric component 201 by a printing process. As an example, the electrodes can be formed on the top of the actuator component 20 in one step. In this case, the electrodes on the top of the actuator component 20 are removed by polishing or the like, thereby separating the external electrodes 223 and 224 from each other.

[0086] Next, as Figure 4 As shown in (a), at the end of the actuator component 20 where the external electrode 223 is formed, which is the side that becomes the base component 10, the electrode is removed to form an electrode removal section 25. At this time, for example, not only the electrode layer 2230 may be removed, but also a chamfered or stepped portion may be formed by partially cutting off the corner of the piezoelectric component on the base component 10 side. Furthermore, as... Figure 4 As shown in (a), in the state before the formation of the groove 23, the electrode layer 2230 is continuously formed in the arrangement direction.

[0087] On the other hand, such as Figure 5 As shown in (a), in FPC 71, for example, a solder coating 74 is formed on a rectangular sheet-like base film 72, on which a wiring layer 73 is formed in a prescribed pattern as a line. The solder coating 74 is formed, for example, on one end side that becomes the bonding area, and extends along the entire length of the column direction.

[0088] Then, the FPC71 is electrically and mechanically connected to one end of the side of the stacked piezoelectric component 201, i.e., the mounting portion, by solder mounting, thereby forming a laminate 200 consisting of the actuator component 20, the solder coating 74, and the substrate film 72 with wiring. At this time, the first region R1 where the solder coating 74 is formed is aligned with the joint of the piezoelectric element 21 and heated to melt the solder in the solder coating 74, thereby electrically and mechanically connecting the FPC71 to the external electrode 223. Heating can be performed using a general heating tool, or by irradiating the substrate film 72 of the FPC71 with an infrared laser or the like. At this time, the positions of each wiring electrode 731 are positioned corresponding to the columnar portions of the components 21 and 22 that are not formed with grooves 23 in subsequent processing steps. The wiring electrodes 731 are configured as lines narrower than the width of the components 21 and 22 and the plating mounting portion 741, thus alleviating the required positioning accuracy.

[0089] Next, as Figure 3 (b) Figure 4 (b) Figure 5 As shown in (b), multiple grooves 23 and 71a are formed on the actuator component 20 and FPC 71 by moving a tool such as a diamond cutter in the Z direction. At this time, multiple grooves 23 and 71a are formed simultaneously at a predetermined interval, dividing the stacked piezoelectric component 201 and FPC 71 into multiple segments, thereby forming multiple columnar elements of multiple piezoelectric elements 21 and 22 arranged at the same interval. Simultaneously, the solder coating 74 is also divided into multiple segments, forming multiple solder mounting portions 741. Thus, multiple driven piezoelectric elements 21, non-driven piezoelectric elements 22, and solder mounting portions 741 are formed at the same interval.

[0090] That is, by processing the groove 71a, multiple mounting parts 71b can be formed respectively. The mounting parts 71b are stacked components consisting of piezoelectric elements 21 and 22 which are part of the piezoelectric component, an external electrode 223 which is part of the electrode layer 2230, a solder mounting part 741 which is made of solder plating film 74, and a base part 721 which is part of the base film 72 and has wiring electrodes 731.

[0091] Here, grooves 23 and 71a remain partially as they do not reach the full length of actuator component 20, thus forming a connecting portion 26 in the area on the side of the base component 10 closer to the bottom surface of groove 23.

[0092] In addition, after the groove 23 is processed, an external electrode 224, which serves as a common electrode, is formed on the other side of the connecting part 26.

[0093] Then, a printed wiring board with head control circuitry is connected to the FPC71.

[0094] Then, on the actuator component 20, the vibrating plate 30, the flow path substrate 405 and the nozzle plate 50 are stacked and positioned by means of a bonding material, a frame portion 60 is arranged on the outer periphery of the actuator component 20, and these multiple components are joined together to complete the liquid ejection head 1.

[0095] According to the liquid ejector head 1 described in the above embodiment, a liquid ejector head with high installability can be provided. That is, by soldering the FPC 71 before the actuator component 20 forms the groove 23, the area of ​​the mounting surfaces of the actuator component 20 and the FPC 71 can be ensured, and the strength of the joint during installation can be improved. Therefore, it is possible to prevent the joint from breaking when stress is applied to the FPC 71 during installation. In addition, since the mounting surface can be enlarged, unevenness is less likely to occur during the joint, and the installation accuracy can be improved. Furthermore, by making the line width of the wiring electrode 731 on the FPC 71 side narrower than the width of the plating mounting portion 741 between the grooves 23, the positional accuracy required during installation can be eased, and positioning becomes easier. Therefore, offset in the spacing direction in the mounting portion can be suppressed, and it is less likely to cause breaks in adjacent wiring or poor joint due to wiring offset.

[0096] Furthermore, the present invention is not limited to the above-described embodiments, and the constituent elements can be modified and embodied in the implementation stage without departing from its spirit.

[0097] Furthermore, in the above embodiment, the piezoelectric layer 211 is configured as a multi-layered piezoelectric layer and the piezoelectric element 21 is driven by longitudinal vibration (d33) in the stacking direction, but it is not limited to this. For example, it can be applied to a method in which the piezoelectric element 21 is composed of a single-layered piezoelectric component, or it can be applied to a method in which it is driven by lateral vibration that is displaced in the d31 direction.

[0098] The arrangement of the nozzles 51 and pressure chambers 31 is not limited to the above-described embodiments. For example, the nozzles 51 may be arranged in two or more rows. In addition, an air chamber as a dummy chamber may be formed between multiple pressure chambers 31. The present invention is not limited to a circulating liquid nozzle, but may also be a non-circulating liquid nozzle, or may be applied to a side-jet type liquid nozzle, but may also be limited to an end injector.

[0099] Furthermore, although an example is shown where piezoelectric elements 21 and 22 have dummy layers 212 at both ends in the stacking direction, this is not a limitation. Dummy layers 212 may be present only on one side of the piezoelectric elements 21 and 22, or the piezoelectric elements 21 and 22 may not have dummy layers 212. Moreover, the structure and positional relationships of various components, including the flow path component 40, the nozzle plate 50, and the frame portion 60, are not limited to the examples described above and can be appropriately modified.

[0100] In addition, in the above embodiment, an example is shown in which two actuator components 20 are arranged side by side on the base component 10, but it is not limited to this, and the number of actuator components 20 may also be singular.

[0101] In addition, the ejected liquid is not limited to printing ink; for example, it can be a device that ejects a liquid containing conductive particles for forming wiring patterns on a printed wiring board.

[0102] Furthermore, in the above embodiments, an example of a liquid ejection device 100 for inkjet printing, etc., is shown, but it is not limited to this. For example, it can also be used in 3D printers, industrial manufacturing machinery, and medical applications, and can achieve miniaturization, lightweighting, and low cost.

[0103] According to at least one embodiment described above, a low-cost and highly installable liquid nozzle can be provided.

[0104] Furthermore, several embodiments of the present invention have been described, but these embodiments are merely illustrative and not intended to limit the scope of the invention. These new embodiments can be implemented in various other ways, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their variations are included within the scope and spirit of the invention, and are included within the scope of the invention as described in the claims and its equivalents.

Claims

1. A liquid ejector head, comprising: The actuator component, at least a portion of which is divided by a plurality of slots, has a plurality of actuator elements having an electrode layer formed on one surface; and A wiring substrate, mounted on one side of the actuator component via a solder layer, is at least partially divided by the slot, and the wiring substrate has a plurality of wiring electrodes configured opposite to the plurality of actuator elements.

2. The liquid ejector head according to claim 1, wherein, The electrode layer and the solder layer are divided by multiple slots, each having multiple individual electrodes and multiple solder mounting portions. Multiple wiring electrodes are connected to multiple solder mounting portions and have a width narrower than the width of the solder mounting portions.

3. The liquid ejector head according to claim 1, wherein, The actuator element is a stacked piezoelectric element.

4. A method for manufacturing a liquid ejector head, wherein, A wiring substrate with wiring is mounted on a piezoelectric component having an electrode layer via a solder layer. After the wiring substrate is installed, a portion of the laminate is divided by forming a plurality of grooves on the overlapping laminate of the piezoelectric component, the electrode layer, the solder layer and the wiring substrate.

5. The method for manufacturing a liquid ejector head according to claim 4, wherein, By forming grooves in the laminate, a plurality of mounting parts are formed, each mounting part having an actuator element formed from a portion of the piezoelectric component, a separate electrode formed from a portion of the electrode layer, a solder mounting portion formed from the solder layer, and a base part formed from a portion of the wiring substrate. The individual electrodes arranged in a parallel direction are continuous with each other before the groove is processed, forming the electrode layer.

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