JP6657844B2 - Liquid ejection device - Google Patents

Description

  The present invention relates to a liquid ejection device.

  An inkjet head used in an inkjet printing apparatus includes a nozzle plate in which a plurality of nozzles are arranged in parallel, and a flow path substrate in which a pressure chamber to which pressure generated by deformation of a piezoelectric element is transmitted is formed. .

  Further, the piezoelectric element is arranged on a diaphragm arranged so as to cover the pressure chamber, and has a common electrode, a piezoelectric layer, and individual electrodes, and each individual electrode has a wiring for the individual electrode. Via a drive circuit.

  As such an ink jet head, a liquid ejecting head is known in which a common electrode lead-out line is connected to a common electrode via contact holes formed at predetermined intervals along the longitudinal direction of a piezoelectric element. (For example, see Patent Document 1). In the liquid jet head disclosed in Patent Document 1, by providing the common electrode lead-out wiring, the resistance value of the common electrode is substantially reduced, and a voltage drop occurs even when a large number of piezoelectric elements are driven simultaneously. That can be prevented.

JP 2006-255972 A

  However, in the liquid ejecting head disclosed in Patent Document 1, no consideration is given to the positional relationship between the common electrode lead-out line and the individual electrode lead-out line. For this reason, there is a possibility that the capacitance generated in the insulating film between the lead wiring and each individual electrode lead wiring may vary. In addition, the length of each of the lead wires for individual electrodes also differs depending on the arrangement position of each individual electrode, and the electric resistance between the respective wires also differs.

  When the capacitance varies, the waveform of the voltage applied to each piezoelectric element varies, and the ink ejection from each nozzle may vary.

  SUMMARY An advantage of some aspects of the invention is to solve the above-described problem and suppress variations in the voltage waveform applied to each piezoelectric element and suppress variations in ink ejection from each nozzle, as compared with a conventional liquid ejection apparatus. It is an object of the present invention to provide a liquid ejecting apparatus that can perform the above-described operations.

  In order to solve the above-mentioned conventional problems, a liquid ejection apparatus according to the present invention includes an insulator film, a common electrode, and a piezoelectric layer disposed on a plurality of pressure chambers forming at least two pressure chamber rows. And a plurality of individual electrodes, having a plurality of piezoelectric elements disposed on the insulator film and corresponding to the plurality of pressure chambers, and a plurality of the individual electrodes disposed on the insulator film. A plurality of individual wirings connected to each, a plurality of connection terminals connected to each of the plurality of individual wirings, a common wiring disposed on the insulator film and connected to the common electrode, A plurality of individual wirings and an insulating material disposed between the plurality of wirings of the common wiring, wherein the individual wirings connected to the individual electrodes far from the connection terminal are connected to a first individual wiring; 1 the individual electrodes are connected more than the individual electrodes connected to each other. When the individual wiring connected to the individual electrode near the terminal is defined as a second individual wiring, the capacitance between the first individual wiring and the common wiring is equal to the second wiring. The capacitance is smaller than the capacitance between the individual wiring and the common wiring.

  The first individual wiring connected to the first individual electrode far from the connection terminal has a higher electric resistance than the second individual wiring connected to the second individual electrode closer to the connection terminal than the first individual electrode. . For this reason, by making the capacitance between the first individual wiring and the common wiring smaller than the capacitance between the second individual wiring and the common wiring, the capacitance between the first individual wiring and the second individual wiring is reduced. Variation in voltage applied to each can be suppressed.

  ADVANTAGE OF THE INVENTION According to the liquid discharge device which concerns on this invention, it becomes possible to suppress the dispersion | variation of the waveform of the voltage applied to each piezoelectric element, and to suppress the dispersion | variation of the ejection of the ink from each nozzle.

FIG. 1 is a schematic diagram illustrating a schematic configuration of an inkjet printer according to a first embodiment. FIG. 3 is a top view of the inkjet head. FIG. 3 is a cross-sectional view of the inkjet head taken along line AA. FIG. 3 is an enlarged view of a main part of the inkjet head. FIG. 3 is a top view of an inkjet head according to a first modification of the first embodiment. FIG. 3 is an enlarged view of a main part of the inkjet head. FIG. 3 is a cross-sectional view of the inkjet head taken along line BB. FIG. 9 is a top view of the inkjet head according to the second embodiment. FIG. 13 is a top view of the ink jet head according to the third embodiment.

  Hereinafter, specific examples of the embodiments will be described with reference to the drawings. In all the drawings, the same or corresponding portions are denoted by the same reference characters, and redundant description will be omitted. In all the drawings, components necessary for describing the present invention are extracted and illustrated, and other components may not be illustrated. Furthermore, the present invention is not limited to the following embodiments.

(Embodiment 1)
[Configuration of inkjet printer]
FIG. 1 is a schematic diagram illustrating a schematic configuration of the inkjet printer according to the first embodiment. In FIG. 1, the front-rear direction and the left-right direction of the inkjet printer are shown as the front-rear direction and the left-right direction in the figure.

  As shown in FIG. 1, an ink jet printer 1 according to the first embodiment includes a carriage 102 movable in a first direction, an ink jet head 103 provided as an example of a liquid ejection device, and provided on the carriage 102. The apparatus includes transport rollers 104A and 104B for transporting the recording paper 105 in a second direction orthogonal to the first direction, and a controller 110, and is configured to eject an ink to the recording paper 105 to record an image. ing. Note that the first direction is the scanning direction of the carriage 102, and the second direction is the transport direction of the recording paper 105.

  The inkjet head 103 is connected to a cartridge holder 108 on which ink cartridges 109A to 109D of four colors of black, yellow, cyan, and magenta are mounted by a tube (not shown).

  Further, the inkjet head 103 includes head units 106 and 107 arranged side by side in the first direction. In the first embodiment, the head unit 106 is configured to eject black and yellow inks, and the head unit 107 is configured to eject cyan and magenta inks.

  The controller 110 includes a CPU, a ROM, a RAM, an EEPROM, an ASIC, and the like. When receiving an input of a print job from an external device such as a PC, the CPU outputs a job execution command to the ASIC based on a program stored in the ROM. The ASIC drives each driver such as a drive circuit 71 to be described later based on this command, and executes a printing process.

  Specifically, the controller 110 ejects ink to the recording paper 105 from the nozzles 50 provided on the lower surfaces of the head units 106 and 107 while the inkjet head 103 moves in the first direction integrally with the carriage 102. Then, an ink ejection operation for recording an image and a transport operation for transporting the recording paper 105 by a predetermined amount in the second direction by the transport rollers 104A and 104B are alternately performed. Note that the recording paper 105 on which the printing process has been completed is transported in the second direction by the transport rollers 104A and 104B, and is discharged to a discharge tray (not shown).

[Configuration of inkjet head]
Next, the configuration of the inkjet head 103 will be described in detail with reference to FIGS. In the following description, the configuration of the head unit 106 will be described as the configuration of the inkjet head 103.

  FIG. 2 is a top view of the inkjet head shown in FIG. FIG. 3 is a cross-sectional view of the inkjet head shown in FIG. 2 taken along line AA. FIG. 4 is an enlarged view of a main part of the inkjet head shown in FIG.

  2 and 4, the first direction and the second direction shown in FIG. 1 are represented as the first direction and the second direction in the drawings. Further, in FIG. 3, the vertical direction of the inkjet head is represented as the vertical direction in the figure. 3 and 4, a part of the ink jet head is omitted.

  As shown in FIGS. 2 to 4, in the inkjet head 103 according to the first embodiment, the reservoir forming member 11, the protection substrate 12, the laminate 13, the flow path forming substrate 14, and the plurality of nozzles 50 are arranged in the second direction. Nozzle plate 15 arranged side by side.

  The nozzle plate 15 has four nozzle rows. In the first embodiment, the two nozzle rows on the left are nozzle rows that eject yellow ink, and the two nozzle rows on the right are nozzle rows that eject black ink. The nozzle plate 15 may be made of a high-molecular synthetic resin material such as polyimide or a metal material such as stainless steel.

  The flow path forming substrate 14 is joined to the upper surface of the nozzle plate 15. A plurality of pressure chambers 60 are formed in the flow path forming substrate 14 so as to communicate with each of the plurality of nozzles 50 when viewed from the thickness direction of the flow path forming substrate 14. That is, four pressure chamber rows 61 in which a plurality of pressure chambers 60 are arranged in parallel in the second direction are formed in the first direction.

  On the upper surface of the flow path forming substrate 14, the laminated body 13 having the vibration plate 41, the piezoelectric element 30 corresponding to each pressure chamber 60, and the like is arranged. The detailed configuration of the laminate 13 will be described later.

  The protection substrate 12 is joined to the upper surface of the second insulating film 38 forming the laminate 13. A recess 12A is formed on the lower surface of the protection substrate 12 so as to extend in the second direction across one row of the piezoelectric elements 30 when viewed from the thickness direction of the protection substrate 12. Each of the piezoelectric elements 30 and the like are housed in the recess 12A.

  The reservoir forming member 11 is joined to the upper surface of the protection substrate 12. On the lower surface of the reservoir forming member 11, a reservoir 11A is formed. The reservoir 11A is connected to the ink cartridge 109A or the ink cartridge 109B of the cartridge holder 108 by a tube (not shown). Thereby, the black ink or the yellow ink is supplied to the reservoir 11A.

  Further, the reservoir forming member 11 is formed with a plurality of ink flow paths 21 that communicate the reservoir 11 </ b> A and each of the pressure chambers 60. Thus, the ink supplied to the reservoir 11A flows through each ink flow path 21 and is supplied to each pressure chamber 60.

[Structure of laminate]
Next, the configuration of the laminate 13 of the inkjet head 103 will be described in detail with reference to FIGS.

  As shown in FIG. 2, a wiring board 70 is joined to the right end of the upper surface of the laminate 13, and a plurality of wirings formed on the wiring board 70 are electrically connected to the plurality of connection terminals 44, respectively. Connected. A drive circuit 71 is mounted on the wiring board 70.

  Further, as described above, the laminate 13 includes the vibration plate 41, the common electrode 31, the piezoelectric layer 32, the plurality of individual electrodes 33, and the like. The diaphragm 41 has an elastic film 39 disposed on the upper surface of the flow path forming substrate 14 and an insulator film 40 disposed on the upper surface of the elastic film 39. In other words, the insulator film 40 is disposed on the plurality of pressure chambers 60 via the flow path forming substrate 14 and the elastic film 39. The elastic film 39 is made of an iron-based alloy such as stainless steel, a copper-based alloy, a nickel-based alloy, a titanium-based alloy, or the like. Further, the insulator film 40 may use a silicon oxide film, a silicon nitride film, or the like.

  A first portion 42 having a U-shape as viewed from the thickness direction of the diaphragm 41 is provided at a peripheral portion of the upper surface of the insulator film 40 that forms the diaphragm 41. The first portion 42 is a portion for electrically connecting the common wiring 34 described later and the wiring board 70.

  Further, when viewed from the thickness direction of the vibration plate 41, a plate-shaped common electrode 31 is provided on a portion of the upper surface of the insulating film 40 inside the first portion 42 provided thereon. A fixed potential is applied to the common electrode 31 via the first portion 42 and the common wiring 34. As a material for forming the common electrode 31, for example, a conductive material such as gold, copper, silver, palladium, platinum, or titanium may be used. Note that the common electrode 31 may be referred to as a fixed electrode. Further, the common wiring 34 may be referred to as a fixed wiring.

  The piezoelectric layer 32 is formed on the upper surface of the common electrode 31 so as to extend in the second direction across a plurality of pressure chambers 60 when viewed from the thickness direction of the vibration plate 41. In other words, the piezoelectric layer 32 is formed so as to cover one pressure chamber row 61. That is, four piezoelectric layers 32 are formed so as to correspond to the four pressure chamber rows 61. As the piezoelectric layer 32, for example, lead zirconate titanate, lead zirconate titanate niobate containing silicon, or the like may be used.

  A plurality of individual electrodes 33 are formed on the upper surface of the piezoelectric layer 32 so as to correspond to the respective pressure chambers 60 when viewed from the thickness direction of the vibration plate 41. As a material forming the individual electrode 33, for example, a conductive material such as gold, copper, silver, palladium, platinum, or titanium may be used. The portions of the common electrode 31, the individual electrodes 33, and the piezoelectric layer 32 sandwiched between the common electrode 31 and the individual electrodes 33 constitute the piezoelectric element 30.

  In the first embodiment, the configuration in which the individual electrodes 33 are disposed above the common electrode 31 is employed. However, the present invention is not limited to this, and the configuration in which the individual electrodes 33 are disposed below the common electrode 31 may be employed. May be adopted. Further, in the first embodiment, as the common electrode 31, one plate-shaped electrode covering the entire individual electrode 33 is disposed so as to be common to the individual electrodes 33. The present invention is not limited thereto, and adopts a form in which a plurality of plate-shaped electrodes are arranged as the common electrode 31 so as to correspond to the individual electrodes 33, that is, to face the individual electrodes 33 with the piezoelectric layer 32 interposed therebetween. Is also good.

  Further, a first insulating film 37 is formed on the upper surface of the insulating film 40 constituting the diaphragm 41 so as to cover the common electrode 31, the piezoelectric layer 32, and the individual electrodes 33. The first insulating film 37 may use an insulator such as an alumina or a silicon nitride film.

  On the upper surface of the first insulating film 37, a common wiring 34, a first individual wiring 35, and a second individual wiring 36 are arranged. In other words, the first insulating film 37 is arranged so as to contact the lower surfaces of the common wiring 34, the first individual wiring 35, and the second individual wiring 36.

  The common wiring 34 is configured to electrically connect the first portion 42 and the common electrode 31. Specifically, one end of the common wiring 34 is connected to an appropriate position on the bottom of the U-shaped first portion 42 which is a portion extending in the second direction. The other end of the common wiring 34 is located between two pressure chamber rows 61 to which black ink is supplied. Then, the common wiring 34 is formed so as to extend along the first direction, passing between the individual electrodes 33 adjacent in the second direction when viewed from the thickness direction of the first insulating film 37.

  In addition, a through hole 43 is formed at an appropriate position on the main surface of the first insulating film 37 so as to overlap with the common wiring 34 when viewed from the thickness direction of the first insulating film 37. The through hole 43 is filled with a conductive material. As the conductive material, the same material as the conductive material forming the common electrode 31 or the individual electrode 33 may be used. For example, gold, copper, silver, palladium, platinum, titanium, or the like may be used.

  The first individual wiring 35 and the second individual wiring 36 are configured to electrically connect the individual electrodes 33 and the connection terminals 44, respectively. Specifically, one ends of the first individual wiring 35 and the second individual wiring 36 are connected to the right end of the individual electrode 33, respectively, and the other ends of the first individual wiring 35 and the second individual wiring 36 are connected to each other. Are connected to the connection terminal 44, respectively. Each of the first individual wiring 35 and the second individual wiring 36 is formed to extend along the first direction when viewed from the thickness direction of the first insulating film 37. Note that the first individual wiring 35 and the second individual wiring 36 may be referred to as individual wirings.

  Here, of the pair of pressure chamber rows 61 to which the same type of ink is supplied, the pressure chamber row 61 far from the connection terminal 44 is defined as a first pressure chamber row 61A, and is connected more than the first pressure chamber row 61A. The pressure chamber row 61 near the terminal 44 is referred to as a second pressure chamber row 61B.

  The individual electrodes 33 corresponding to the pressure chambers 60 forming the first pressure chamber row 61A to which the yellow ink is supplied are set as the first individual electrodes 33A, and the pressure forming the second pressure chamber row 61B to which the yellow ink is supplied. The individual electrode 33 corresponding to the chamber 60 is a second individual electrode 33B. Further, the individual electrodes 33 corresponding to the pressure chambers 60 constituting the first pressure chamber row 61A to which the black ink is supplied are set as third individual electrodes 33C, and the pressure constituting the second pressure chamber row 61B to which the black ink is supplied. The individual electrode 33 corresponding to the chamber 60 is a fourth individual electrode 33D.

  Hereinafter, the individual wires connected to the individual electrodes 33 will be described in detail with reference to FIGS.

  The second individual wiring 36B connected to the fourth individual electrode 33D is formed to extend along the first direction. Further, the first individual wiring 35B connected to the third individual electrode 33C is formed so as to extend between the fourth individual electrodes 33D, 33D adjacent in the second direction and extend along the first direction. I have.

  The second individual wiring 36A connected to the second individual electrode 33B passes between the third individual electrodes 33C and 33C and between the fourth individual electrodes 33D and 33D, which are adjacent in the second direction, to form the first individual wiring 36A. It is formed so as to extend along the direction. Further, the first individual wiring 35A connected to the first individual electrode 33A is adjacent to each other in the second direction between the second individual electrodes 33B, 33B, between the third individual electrodes 33C, 33C, and the fourth individual electrode. It is formed so as to extend along the first direction through the space between 33D and 33D.

  Then, as shown in FIG. 2, counting from the end in the first direction, the first individual wiring 35A, the second individual wiring 36A, and the common wiring 34 located on the same n-th row are common to the first individual wiring 35A. The capacitance between the second wiring 36A and the common wiring 34 is smaller than the capacitance between the second individual wiring 36A and the common wiring 34.

  Specifically, in a region between the second individual electrode 33B and the connection terminal 44 in the first direction, the first individual wiring 35A is provided at a position farther from the common wiring 34 than the second individual wiring 36A. Have been. More specifically, in the region between the third individual electrode 33C located on the n-th row and the third individual electrode 33C located on the (n + 1) -th row adjacent to each other in the second direction, the first individual wiring 35A Are disposed farther from the common wiring 34 than the second individual wiring 36A.

  A second insulating film 38 is formed on the upper surface of the first insulating film 37 so as to cover the upper surfaces and side surfaces of the piezoelectric layer 32, the individual electrodes 33, the common wiring 34, the first individual wiring 35, and the second individual wiring 36. Are located.

  Note that the second insulating film 38 disposed between the common wiring 34 and the first individual wiring 35 and the second insulating film 38 disposed between the common wiring 34 and the second individual wiring 36 are made of an insulating material. 45 is an example. In addition, the second insulating film 38 may use an insulator such as a silicon oxide film. Further, the insulating material 45 has a length in the normal direction of the main surface of the vibration plate 41 in the first normal wiring 35, the second individual wiring 36, and the common wiring 34 in the normal direction of the main surface of the vibration plate 41. It is longer than the length.

  Next, referring to FIG. 4, the individual wiring connected to each individual electrode 33 will be described from another viewpoint.

  As shown in FIG. 4, the individual electrode 33 arranged on one side in the first direction, that is, the left side of FIG. 4 is defined as one side individual electrode 33 </ b> E, and the other side in the first direction, that is, on the right side of FIG. The arranged individual electrode 33 is referred to as the other-side individual electrode 33G. In the first direction, the individual electrode 33 disposed between the one-side individual electrode 33E and the other-side individual electrode 33G is defined as an inner individual electrode 33F, and the individual electrode adjacent to the other-side individual electrode 33G in the second direction. 33 is an adjacent individual electrode 33H. Further, the individual wiring connected to the one-side individual electrode 33E is referred to as one-side individual wiring 35E, and the individual wiring connected to the inner individual electrode 33F is referred to as an inner individual wiring 36F.

  The one-side individual wiring 35E is formed to extend from the contact point with the one-side individual electrode 33E to between the other-side individual electrode 33G and the adjacent individual electrode 33H. The inner individual wiring 36F is formed to extend from the contact point with the inner individual electrode 33F to between the other individual electrode 33G and the adjacent individual electrode 33H. Further, the one-side individual wiring 35E is formed such that the length of the wiring is longer than the inner individual wiring 36F.

  Then, in a region between the other-side individual electrode 33G and the adjacent individual electrode 33H, the one-side individual wiring 35E is provided at a position farther from the common wiring 34 than the inner individual wiring 36F.

[Operation of inkjet head]
Next, the operation of the inkjet head 103 according to the first embodiment will be described with reference to FIGS.

  First, it is assumed that the controller 110 has received an input of a print job from an external device such as a PC. Then, the CPU of the controller 110 outputs a job execution command to the ASIC based on the program stored in the ROM. The ASIC outputs a control signal to the drive circuit 71 based on this command. The drive circuit 71 outputs a drive signal for driving the piezoelectric element 30 to the connection terminal 44 via the wiring of the wiring board 70 based on the control signal output from the controller 110.

  The drive signal input to the connection terminal 44 is supplied to the individual electrode 33 via each first individual wiring 35 or each second individual wiring 36. When a drive signal is input to the individual electrode 33, a drive potential is applied to the individual electrode 33, and a potential difference occurs between the individual electrode 33 and the common wiring 34. Due to this potential difference, the piezoelectric layer 32 extends in the thickness direction and contracts in the plane direction.

  As the piezoelectric layer 32 contracts and deforms, the diaphragm 41 flexes in a convex shape toward the pressure chamber 60. Accordingly, a pressure wave is generated in the pressure chamber 60, and the ink in the pressure chamber 60 is ejected from the nozzle 50.

  In the inkjet head 103 according to the first embodiment thus configured, as shown in FIG. 2, the first individual wiring 35A and the second individual wiring 35A located at the same n-th row counted from the end in the first direction. The individual wiring 36A and the common wiring 34 are configured such that the capacitance between the first individual wiring 35A and the common wiring 34 is smaller than the capacitance between the second individual wiring 36A and the common wiring 34. It is arranged.

  Here, the first individual electrode 33A to which the first individual wiring 35A is connected is disposed at a position farther from the connection terminal 44 than the second individual electrode 33B to which the second individual wiring 36A is connected. I have. For this reason, since the first individual wiring 35A is arranged such that the length of the wiring is longer than the second individual wiring 36A, the first individual wiring 35A has a higher electrical resistance than the second individual wiring 36A. large.

  For this reason, by making the capacitance between the first individual wiring 35A and the common wiring 34 smaller than the capacitance between the second individual wiring 36A and the common wiring 34, the capacitance between the first individual wiring 33A and the common wiring 34 is reduced. Variations in the rise time and fall time of the voltage input to each of the second individual electrodes 33B can be suppressed.

  Accordingly, in the inkjet head 103 according to the first embodiment, the first individual corresponding to the pressure chambers 60 constituting the two first pressure chamber rows 61A and the second pressure chamber rows 61B for ejecting the same color ink is provided. Variation in the voltage input to each of the electrode 33A and the second individual electrode 33B can be suppressed. Therefore, it is possible to suppress variations in the timing of ejecting ink from each nozzle 50 of the plurality of pressure chambers 60 to which the same color ink is supplied.

  Further, in the inkjet head 103 according to the first embodiment, as shown in FIG. 4, in the region between the other-side individual electrode 33G and the adjacent individual electrode 33H, the one-side individual wiring 35E is , Are arranged at positions farther than the inner individual wiring 36F. The one-side individual wiring 35E is formed so that the length of the wiring is longer than the inner individual wiring 36F.

  Therefore, by making the capacitance between the one-side individual wiring 35E and the common wiring 34 smaller than the capacitance between the inner individual wiring 36F and the common wiring 34, the capacitance between the one-side individual wiring 33E and the other is reduced. Variations in the rise time and fall time of the voltage input to each of the side individual electrodes 33G can be suppressed.

  Thereby, in the ink jet head 103 according to the first embodiment, the timing of the ink ejected from the nozzle 50 of the pressure chamber 60 corresponding to the one-side individual wiring 35E and the nozzle of the pressure chamber 60 corresponding to the inner individual wiring 36F. Variations in the timing of the ink ejected from the nozzle 50 can be suppressed.

  In the inkjet head 103 according to the first embodiment, the insulating material 45 has a length in the normal direction of the main surface of the diaphragm 41, the first individual wiring 35, the second individual wiring 36, and the common wiring 34. Is longer than the length of the main surface of the diaphragm 41 in the normal direction.

  Accordingly, the capacitance between the first individual wiring 35A and the common wiring 34 and the capacitance between the second individual wiring 36A and the common wiring 34 can be increased. Therefore, by increasing the influence of the capacitance on the rise time and fall time of the voltage, the rise time and fall time of the voltage due to the difference in resistance between the first individual wiring 35A and the second individual wiring 36A are increased. Can be reduced.

  Therefore, in the ink jet head 103 according to the first embodiment, occurrence of variations in the rise time and the fall time of the voltage input to each of the first individual electrode 33A and the second individual electrode 33B is suppressed, Variations in the ejection of ink from each nozzle 50 can be suppressed.

  Further, in the inkjet head 103 according to the first embodiment, the first individual wiring 35, the second individual wiring 36, and the common wiring 34 are formed on the upper surface of the first insulating film 37. Therefore, these wirings can be formed by the same process, and the manufacturing cost of the inkjet head 103 can be reduced.

[Modification 1]
Next, a modified example of the inkjet head according to the first embodiment will be described.

  FIG. 5 is a top view of the inkjet head according to the first modification of the first embodiment. FIG. 6 is an enlarged view of a main part of the inkjet head shown in FIG. FIG. 7 is a cross-sectional view of the inkjet head shown in FIG. 5 taken along line BB.

  5 and 6, the first direction and the second direction shown in FIG. 1 are represented as the first direction and the second direction in the drawings. In FIG. 7, the vertical direction of the inkjet head is shown as the vertical direction in the figure. Further, in FIG. 7, a part of the inkjet head is omitted.

  As shown in FIGS. 5 to 7, the inkjet head 103 according to the first modification has the same basic configuration as the inkjet head 103 according to the first embodiment, but the third individual electrode 33C adjacent in the second direction is used. , 33C, the arrangement positions of the common wiring 34, the first individual wiring 35A, and the second individual wiring 36A are different.

  Specifically, the common wiring 34, the second individual wiring 36A, and the first individual wiring 35A are located on the third individual electrode 33C located on the n-th row and the n + 1-th row, counting from the end in the second direction. In a region between the third individual electrode 33C and the third individual electrode 33C, they are arranged so as to overlap each other. More specifically, in this area, the common wiring 34, the second individual wiring 36A, and the first individual wiring 35A are arranged in this order upward. That is, the second individual wiring 36A is disposed above the common wiring 34, and the first individual wiring 35A is disposed above the second individual wiring 36A.

  In a region other than the region between the third individual electrode 33C located on the n-th row and the third individual electrode 33C located on the (n + 1) -th row, the common wiring 34, the first individual wiring 35A, and the second individual wiring 35A The wiring 36A is disposed on the upper surface of the first insulating film 37, and the second insulating film 38 is formed so as to cover these wirings.

  Further, in a region between the third individual electrode 33C located on the n-th row and the third individual electrode 33C located on the (n + 1) -th row, an area between the upper surface of the second individual wiring 36A and the lower surface of the first individual wiring 35A is provided. The third insulating film 46 is formed so as to cover the second individual wiring 36 </ b> A and the second insulating film 38. Further, a fourth insulating film 47 is formed so as to cover the upper surface and the side surface of the first individual wiring 35A.

  The second insulating film 38 disposed between the common wiring 34 and the second individual wiring 36A is an example of the insulating material 45. The third insulating film 46 disposed between the second individual wiring 36A and the first individual wiring 35A is another example of the insulating material 45.

  The first individual wiring 35A disposed on the upper surface of the third insulating film 46 is provided on the upper surface of the first insulating film 37 via the conductive material filled in the through hole 48. It is electrically connected to the individual wiring 35A. The through-hole 48 is provided near the through-hole 43, and includes the first individual wiring 35 </ b> A disposed on the upper surface of the third insulating film 46 and the first individual wiring 35 </ b> A disposed on the upper surface of the first insulating film 37. Are provided in the second insulating film 38 and the third insulating film 46 so as to communicate with.

  In addition, the second individual wiring 36 </ b> A disposed on the upper surface of the third insulating film 46 is separated from the second individual wiring 36 </ b> A disposed on the upper surface of the first insulating film 37 via the conductive material filled in the through hole 49. It is electrically connected to the wiring 36A. The through hole 49 is provided in the vicinity of the through hole 43, and the second individual wiring 36 </ b> A disposed on the upper surface of the second insulating film 38 and the second individual wiring 36 </ b> A disposed on the upper surface of the first insulating film 37. Are provided on the second insulating film 38 so as to communicate with.

  Even in the ink jet head 103 of the first modification having the above-described configuration, the first individual wiring 35A is disposed at a position farther from the common wiring 34 than the second individual wiring 36A. The capacitance between the first individual wiring 35 and the common wiring 34 can be made smaller than the capacitance between the second individual wiring 36 and the common wiring 34.

  Therefore, the ink jet head 103 according to the first modification has the same operation and effect as the ink jet head 103 according to the first embodiment.

  In the inkjet head 103 according to the first modification, the common wiring 34, the first individual wiring 35, and the second individual wiring 36 are stacked in the thickness direction of the first insulating film 37. Cannot be formed by

  However, since these wirings overlap when viewed from the thickness direction of the first insulating film 37, the distance between the individual electrodes 33, 33 adjacent in the second direction can be reduced.

  For this reason, in the ink jet head 103 of the first modification, the number of arrangements of the individual electrodes 33 per unit area, that is, the number of the individual electrodes 33 arranged in the second direction can be increased. Therefore, the individual electrodes 33 can be arranged at a high density, and the resolution of the inkjet head can be increased.

(Embodiment 2)
[Configuration of inkjet head]
FIG. 8 is a top view of the inkjet head according to the second embodiment. In FIG. 8, the first direction and the second direction in FIG. 1 are represented as the first direction and the second direction in the figure.

  As shown in FIG. 8, the inkjet head 103 according to the second embodiment has the same basic configuration as the inkjet head 103 according to the first embodiment, except for the following points. Different from the head 103.

  In the inkjet head 103 according to the second embodiment, two pressure chamber rows 61 are formed in the first direction. Accordingly, two rows of the individual electrodes 33 and the nozzles 50 arranged side by side in the second direction are also formed in the first direction.

  In the inkjet head 103 according to the second embodiment, two through holes 43 are provided between the adjacent individual electrodes 33 in the first direction. A conductive material forming the common wiring 34 is not provided between the two through holes 43, 43 on the upper surface of the first insulating film 37. In these sections, the common electrode 31 is connected to the common wiring 34. Is part of.

  In the inkjet head 103 according to the second embodiment, one end of the second individual wiring 36A is connected to the left end of the second individual electrode 33B. The second individual wiring 36A is formed to extend along the first direction in a region between the second individual electrodes 33B, 33B adjacent in the second direction.

  Further, in the inkjet head 103 according to the second embodiment, the first individual wiring 35A, the second individual wiring 36A, and the common wiring 34 located on the same n-th row counted from the end in the second direction In a region between the second individual electrode 33B located at the eye and the second individual electrode 33B located at the (n + 1) th row, the first individual wiring 35A is farther from the common wiring 34 than the second individual wiring 36A. It is located at the location.

  Thereby, the capacitance between the first individual wiring 35 and the common wiring 34 can be made smaller than the capacitance between the second individual wiring 36 and the common wiring 34. Therefore, the ink jet head 103 according to the second embodiment has the same operation and effect as the ink jet head 103 according to the first embodiment.

(Embodiment 3)
[Configuration of inkjet head]
FIG. 9 is a top view of the inkjet head according to the third embodiment. In FIG. 9, the first direction and the second direction in FIG. 1 are represented as the first direction and the second direction in the figure.

  As shown in FIG. 9, the inkjet head 103 according to the third embodiment has the same basic configuration as the inkjet head 103 according to the first embodiment, except for the following points. Different from the head 103.

  In the inkjet head 103 according to the third embodiment, similarly to the inkjet head 103 according to the second embodiment, two pressure chamber rows 61 are formed in the first direction. Accordingly, two rows of the individual electrodes 33 and the nozzles 50 arranged side by side in the second direction are also formed in the first direction.

  In the inkjet head 103 according to the third embodiment, in the region between the second individual electrode 33B and the connection terminal 44 in the first direction, the first individual wiring 35A is It is arranged at a position farther than the individual wiring 36A.

  Thereby, the capacitance between the first individual wiring 35 and the common wiring 34 can be made smaller than the capacitance between the second individual wiring 36 and the common wiring 34. Therefore, the ink jet head 103 according to the third embodiment has the same operation and effect as the ink jet head 103 according to the first embodiment.

  From the above description, many modifications and other embodiments of the present invention are obvious to one skilled in the art. Therefore, the above description should be construed as illustrative only and is provided for the purpose of teaching those skilled in the art the best mode of carrying out the invention. Details of its structure and / or function may be substantially changed without departing from the spirit of the invention. Further, various inventions can be formed by appropriately combining a plurality of components disclosed in the above embodiments.

Reference Signs List 11 reservoir forming member 11A reservoir 12 protective substrate 12A recess 13 laminated body 14 flow path forming substrate 15 nozzle plate 21 ink flow path 30 piezoelectric element 31 common electrode 32 piezoelectric layer 33 individual electrode 34 common wiring 35 first individual wiring 36 second individual Wiring 37 First insulating film 38 Second insulating film 39 Elastic film 40 Insulator film 41 Vibrating plate 42 Intermediate electrode 43 Through hole 44 Connection terminal 45 Insulating material 50 Nozzle 60 Pressure chamber 61 Pressure chamber row

Claims (9)

An insulator film disposed on a plurality of pressure chambers forming at least two pressure chamber rows;
A common electrode, a piezoelectric layer, and an individual electrode, having a plurality of piezoelectric elements disposed on the insulator film and corresponding to the plurality of pressure chambers,
A plurality of individual wirings arranged on the insulator film and connected to the plurality of individual electrodes,
A plurality of connection terminals connected to each of the plurality of individual wirings,
A common wiring disposed on the insulator film and connected to the common electrode;
An insulating material disposed between the plurality of individual wirings and the plurality of wirings of the common wiring,
A first insulating film that is in contact with the lower surface of the individual wiring and the common wiring, and a second insulating film that is arranged to cover the upper surface and side surfaces of the individual electrode and the common electrode,
The insulating material is a part of a second insulating film disposed between the plurality of individual wirings and the plurality of wirings of the common wiring;
The individual wiring connected to the individual electrode far from the connection terminal is connected to a first individual wiring and the individual electrode located closer to the connection terminal than the individual electrode connected to the first individual wiring. When the individual wiring that is performed is defined as a second individual wiring,
The liquid ejection device according to claim 1, wherein a capacitance between the first individual wiring and the common wiring is smaller than a capacitance between the second individual wiring and the common wiring. The normal length of the main surface of the insulator film of the insulating material, characterized in that said at the normal direction than the length of the individual wiring, the liquid ejecting apparatus according to claim 1 . The plurality of pressure chambers configuring the two pressure chamber rows are configured such that ink of the same color flows therethrough,
The first individual wiring is connected to the individual electrode corresponding to the pressure chamber forming one of the two pressure chamber rows,
The second individual wiring among the pressure chamber rows of the two rows, are connected to the individual electrode corresponding to the pressure chambers constituting the other of the pressure chamber rows, the liquid ejection according to claim 1 or 2 apparatus. The direction in which the two pressure chamber rows are juxtaposed is referred to as a first direction, the direction orthogonal to the first direction is referred to as a second direction, and the individual electrodes to which the first individual wirings are connected are defined as first individual When the individual electrode to which the second individual wiring is connected is defined as a second individual electrode,
The first individual wiring, the second individual wiring, and the common wiring located in the n-th row, counting from the end in the second direction, are provided between the second individual electrode and the connection terminal in the first direction. in the region between the first individual wiring, with respect to the common line, the second is arranged at a position farther than the individual wires, the liquid discharge according to any one of claims 1 to 3 apparatus. The direction in which the two pressure chamber rows are juxtaposed is referred to as a first direction, the direction orthogonal to the first direction is referred to as a second direction, and the individual electrodes to which the first individual wirings are connected are defined as first individual When the individual electrode to which the second individual wiring is connected is defined as a second individual electrode,
Counting from the end in the second direction, the first individual wiring, the second individual wiring, and the common wiring located on the n-th row are the same as the second individual electrode located on the n-th row and the n + 1-th row. in the region between the second individual electrodes positioned, the first individual wiring, with respect to the common line is disposed at a position farther than the second individual wiring, according to claim 1-4 The liquid ejection device according to claim 1. The direction in which the two pressure chamber rows are juxtaposed is referred to as a first direction, the direction orthogonal to the first direction is referred to as a second direction, and the individual electrodes to which the first individual wirings are connected are defined as first individual An electrode, wherein the individual electrode to which the second individual wiring is connected is a second individual electrode, and the individual electrode disposed closer to the connection terminal than the second individual electrode in the first direction is When defined as the third individual electrode,
Counting from the end in the second direction, the first individual wiring, the second individual wiring, and the common wiring located on the n-th row include the third individual electrode located on the n-th row and the (n + 1) -th row. The first individual wiring is disposed at a position farther than the second individual wiring with respect to the common wiring in a region between the third individual electrode and the third individual electrode. 6. The liquid ejecting apparatus according to any one of 5 . An insulator film disposed on a plurality of pressure chambers forming at least two pressure chamber rows;
A common electrode, a piezoelectric layer, and an individual electrode, having a plurality of piezoelectric elements disposed on the insulator film and corresponding to the plurality of pressure chambers,
A plurality of individual wirings arranged on the insulator film and connected to the plurality of individual electrodes,
A plurality of connection terminals connected to each of the plurality of individual wirings,
A common wiring disposed on the insulator film and connected to the common electrode;
An insulating material disposed between the plurality of individual wirings and the plurality of wirings of the common wiring,
The individual wiring connected to the first individual electrode that is the individual electrode far from the connection terminal is a first individual wiring, and the individual electrode that is a position closer to the connection terminal than the first individual electrode is The individual wiring connected to the two individual electrodes is defined as a second individual wiring, a direction in which the two pressure chamber rows are juxtaposed is defined as a first direction, and a direction orthogonal to the first direction is defined as a second direction. If defined,
The first individual wiring, the second individual wiring, and the common wiring located in the n-th row, counting from the end in the second direction, are provided between the second individual electrode and the connection terminal in the first direction. In a region between, the first individual wiring is disposed at a position farther from the common wiring than the second individual wiring ,
Counting from the end in the second direction, the first individual wiring, the second individual wiring, and the common wiring located on the n-th row are the same as the second individual electrode located on the n-th row and the n + 1-th row. The liquid discharge device , wherein the first individual wiring is disposed at a position farther from the common wiring in a region between the second individual electrode and the second individual wiring . In the first direction, when the individual electrode arranged closer to the connection terminal than the second individual electrode is defined as a third individual electrode,
Counting from the end in the second direction, the first individual wiring, the second individual wiring, and the common wiring located on the n-th row include the third individual electrode located on the n-th row and the (n + 1) -th row. in the region between the said third individual electrodes, which is located, the first individual wiring, with respect to the common line is disposed at a position farther than the second individual wiring to claim 7 The liquid ejection device according to claim 1.   An insulator film disposed on a plurality of pressure chambers forming at least two pressure chamber rows;
  A common electrode, a piezoelectric layer, and an individual electrode, having a plurality of piezoelectric elements disposed on the insulator film and corresponding to the plurality of pressure chambers,
  A plurality of individual wirings arranged on the insulator film and connected to the plurality of individual electrodes,
  A plurality of connection terminals connected to each of the plurality of individual wirings,
  A common wiring disposed on the insulator film and connected to the common electrode;
  An insulating material disposed between the plurality of individual wirings and the plurality of wirings of the common wiring,
  The individual wiring connected to the individual electrode far from the connection terminal is connected to a first individual wiring and the individual electrode located closer to the connection terminal than the individual electrode connected to the first individual wiring. When the individual wiring that is performed is defined as a second individual wiring,
  The capacitance between the first individual wiring and the common wiring is smaller than the capacitance between the second individual wiring and the common wiring,
  The direction in which the two pressure chamber rows are juxtaposed is referred to as a first direction, the direction orthogonal to the first direction is referred to as a second direction, and the individual electrodes to which the first individual wirings are connected are defined as first individual When the individual electrode to which the second individual wiring is connected is defined as a second individual electrode,
  Counting from the end in the second direction, the first individual wiring, the second individual wiring, and the common wiring located on the n-th row are the same as the second individual electrode located on the n-th row and the n + 1-th row. The liquid discharge device, wherein the first individual wiring is disposed at a position farther from the common wiring in a region between the second individual electrode and the second individual wiring.

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