阅读说明：本技术 液体喷射头、液体喷射装置以及配线基板 (Liquid ejecting head, liquid ejecting apparatus, and wiring board ) 是由 渡边峻介 富松慎吾 于 2019-06-21 设计创作，主要内容包括：本发明提供一种提高了第一端子与第二端子之间的电连接的可靠性的液体喷射头、液体喷射装置以及配线基板。该液体喷射头具备：头单元,其包括安装面,在所述安装面上形成有被供给用于从喷嘴喷射液体的信号的多个第一端子；可挠性的配线基板,其包含用于向所述头单元供给所述信号的多个第二端子,并在该第二端子和所述第一端子被电连接的状态下通过非导电性膏而与所述头单元接合,所述多个第二端子以50μm以下的间距而被排列,在所述第二端子的表面上形成有突出部,所述突出部与所述第一端子的表面接触,并以超过该第二端子的表面粗糙度的高度而突出。(The invention provides a liquid ejecting head, a liquid ejecting apparatus, and a wiring board, in which reliability of electrical connection between a first terminal and a second terminal is improved. The liquid ejecting head includes: a head unit including a mounting surface on which a plurality of first terminals to which signals for ejecting liquid from nozzles are supplied are formed; and a flexible wiring board including a plurality of second terminals for supplying the signals to the head unit, the second terminals being joined to the head unit via a non-conductive paste in a state where the second terminals and the first terminals are electrically connected, the plurality of second terminals being arranged at a pitch of 50 μm or less, the plurality of second terminals having a protrusion portion formed on a surface thereof, the protrusion portion being in contact with the surface of the first terminal and protruding at a height exceeding a surface roughness of the second terminal.)

1. A liquid ejecting head includes:

a head unit including a mounting surface on which a plurality of first terminals to which signals for ejecting liquid from nozzles are supplied are formed;

a flexible wiring board including a plurality of second terminals for supplying the signals to the head unit, and bonded to the head unit via a non-conductive paste in a state where the second terminals and the first terminals are electrically connected,

the plurality of second terminals are arranged at a pitch of 50 μm or less,

a protruding portion that is in contact with the surface of the first terminal and protrudes at a height exceeding the surface roughness of the second terminal is formed on the surface of the second terminal.

2. The liquid ejection head according to claim 1,

in two adjacent second terminals among the plurality of second terminals, positions of the protruding portions in a direction in which the second terminals extend are different.

3. The liquid ejection head as claimed in claim 1 or claim 2,

the plurality of protruding portions are formed on the surface of the second terminal along a direction in which the second terminal extends.

4. The liquid ejecting head as claimed in claim 3,

an interval between two adjacent protruding portions among the plurality of protruding portions formed on the second terminal is larger than a length of the protruding portions in a direction in which the second terminal extends.

5. The liquid ejection head as claimed in claim 1 or claim 2,

an interval between two mutually adjacent second terminals of the plurality of second terminals is larger than a length of the protruding portion in a direction in which the second terminals extend.

6. A liquid ejecting apparatus includes:

the liquid ejection head as claimed in any one of claim 1 to claim 5.

7. A flexible wiring board joined to a head unit via a non-conductive paste, the head unit including a mounting surface on which a plurality of first terminals to which signals for ejecting liquid from nozzles are supplied are formed,

the wiring board includes a plurality of second terminals electrically connected to the plurality of first terminals and configured to supply the signals to the head unit,

the plurality of second terminals are arranged at a pitch of 50 μm or less,

a protruding portion that is in contact with the surface of the first terminal and protrudes at a height exceeding the surface roughness of the second terminal is formed on the surface of the second terminal.

8. The wiring substrate according to claim 7,

the height of the protruding portion is greater than half the thickness of the second terminal at the protruding portion.

Technical Field

The present invention relates to a technique for ejecting a liquid such as ink.

Background

For example, patent document 1 discloses a liquid ejecting apparatus that ejects liquid by supplying a drive signal to a piezoelectric element. A wiring board on which an input terminal to which a drive signal for driving the piezoelectric element is input is bonded to a flexible board for supplying the drive signal to the wiring board.

In the technique of patent document 1, when both the surface of the input terminal of the wiring board and the surface of the terminal of the flexible board are flat, the terminals may not be in sufficient contact with each other, and the reliability of the electrical connection between the terminals may be lowered.

Patent document 1: japanese patent laid-open publication No. 2017-164944

Disclosure of Invention

In order to solve the above problem, a liquid ejecting head according to a preferred embodiment of the present invention includes: a head unit including a mounting surface on which a plurality of first terminals to which signals for ejecting liquid from nozzles are supplied are formed; and a flexible wiring board including a plurality of second terminals for supplying the signals to the head unit, the second terminals being joined to the head unit via a non-conductive paste in a state where the second terminals and the first terminals are electrically connected, the plurality of second terminals being arranged at a pitch of 50 μm or less, the plurality of second terminals having a protrusion portion formed on a surface thereof, the protrusion portion being in contact with the surface of the first terminal and protruding at a height exceeding a surface roughness of the second terminal.

Drawings

Fig. 1 is a block diagram showing a configuration of a liquid ejecting apparatus according to a first embodiment of the present invention.

Fig. 2 is an exploded perspective view of the head unit.

Fig. 3 is a sectional view of the head unit (sectional view taken along line III-III in fig. 2).

Fig. 4 is a waveform diagram of a driving signal.

Fig. 5 is a block diagram showing a functional configuration of the liquid ejecting apparatus.

Fig. 6 is a plan view and a cross-sectional view of the second wiring board.

Fig. 7 is a cross-sectional view (cross-sectional view taken along line VII-VII in fig. 6) of the first wiring board and the second wiring board bonded to each other.

Fig. 8 is a cross-sectional view of the first wiring board and the second wiring board in a state of being joined (cross-sectional view taken along line VIII-VIII in fig. 6).

Fig. 9 is a cross-sectional view (cross-sectional view taken along line IX-IX in fig. 6) of the first wiring board and the second wiring board in a state where the first wiring board and the second wiring board are bonded.

Fig. 10 is a plan view of the second wiring board according to the second embodiment.

Fig. 11 is a plan view of the second wiring board according to the third embodiment.

Detailed Description

First embodiment

Fig. 1 is a configuration diagram illustrating a liquid ejecting apparatus 100 according to a first embodiment of the present invention. The liquid ejecting apparatus 100 according to the first embodiment is an ink jet printing apparatus that ejects ink, which is an example of a liquid, onto a medium 12. The medium 12 is typically a printing paper, but a printing object made of any material such as a resin film or a fabric is used as the medium 12. As illustrated in fig. 1, the liquid ejecting apparatus 100 is provided with a liquid container 14 that stores ink. For example, an ink cartridge that is attachable to and detachable from the liquid ejecting apparatus 100, a bag-shaped ink bag formed of a flexible film, or an ink tank that can replenish ink is used as the liquid container 14. A plurality of inks different in color are stored in the liquid container 14.

As illustrated in fig. 1, the liquid ejecting apparatus 100 includes a control unit 20, a transport mechanism 22, and a line head 26. The control Unit 20 includes a Processing circuit such as a CPU (Central Processing Unit) or an FPGA (Field Programmable gate array) and a memory circuit such as a semiconductor memory, and collectively controls the respective elements of the liquid ejecting apparatus 100. The transport mechanism 22 transports the medium 12 in the Y direction under control performed by the control unit 20.

The line head 26 includes a plurality of liquid ejecting heads 261. Each of the liquid ejecting heads 261 is a structure that ejects ink from nozzles. The plurality of liquid ejecting heads 261 are arranged along the X direction orthogonal to the Y direction. For example, a plurality of liquid ejecting heads 261 are arranged in a staggered arrangement or a staggered arrangement. Each of the liquid ejecting heads 261 ejects ink supplied from the liquid container 14 to the medium 12 under control performed by the control unit 20. By causing the liquid ejecting heads 261 to eject ink onto the medium 12 in parallel with the conveyance of the medium 12 by the conveyance mechanism 22, a desired image is formed on the surface of the medium 12. Hereinafter, a direction perpendicular to an X-Y plane parallel to the surface of the medium 12 is referred to as a Z direction. The ejection direction of the ink ejected from each of the liquid ejecting heads 261 corresponds to the Z direction. The Z direction is typically vertical.

Fig. 2 is an exploded perspective view of the line head 26, and fig. 3 is a sectional view taken along line III-III in fig. 2. As illustrated in fig. 2, the liquid ejecting head 261 includes a plurality of nozzles N arranged in the X direction. The plurality of nozzles N of the first embodiment are divided into a first row L1 and a second row L2 that are arranged in parallel with a space therebetween in the Y direction. Each of the first row L1 and the second row L2 is a set of a plurality of nozzles N arranged linearly in the Y direction. Further, although there is a possibility that the positions of the nozzles N in the Y direction are different between the first row L1 and the second row L2 (that is, staggered arrangement or staggered arrangement), hereinafter, for convenience of explanation, a configuration in which the positions of the nozzles N in the Y direction are aligned in the first row L1 and the second row L2 is illustrated. As understood from fig. 3, the liquid ejecting head 261 of the first embodiment has a structure in which elements related to the nozzles N of the first row L1 and elements related to the nozzles N of the second row L2 are arranged substantially in line symmetry.

As illustrated in fig. 2 and 3, each of the liquid ejecting heads 261 includes a head unit 611 that ejects ink from the nozzles N, and a second wiring board 613. The control unit 20 and the head unit 611 are electrically connected by the second wiring substrate 613. The control unit 20 of fig. 1 generates a signal for ejecting ink from the nozzles and a voltage. For example, the control signal S and the drive signal D are generated by the control unit 20. The control signal S indicates the presence or absence of ejection (ejection/non-ejection) of ink for each nozzle N. The drive signal D is a periodic signal in which a voltage is changed with reference to a predetermined voltage, and is used to cause the head unit 611 to eject ink. As illustrated in fig. 4, the drive signal D is a voltage signal including a drive pulse P for each predetermined period. Further, a drive signal D having a waveform including a plurality of drive pulses P may be used. The driving signal D and the control signal S generated by the control unit 20 are supplied to the head unit 611 via the second wiring substrate 613.

As illustrated in fig. 2 and 3, the head unit 611 includes the flow channel structure 30, the piezoelectric element 44, the first wiring board 46, the housing 48, and the drive circuit 80. The flow channel structure 30 is a structure that forms a flow channel for supplying ink to the plurality of nozzles N. The flow channel structure 30 of the first embodiment is composed of a flow channel substrate 32, a pressure chamber substrate 34, a vibration plate 42, a nozzle plate 62, and a first vibration absorber 64. Each member constituting the flow channel structure 30 is a plate-like member elongated in the X direction. On the surface on the negative side in the Z direction of the flow path substrate 32, a housing 48 and a pressure chamber substrate 34 are provided. On the other hand, on the surface on the positive side in the Z direction in the flow channel substrate 32, a nozzle plate 62 and a first vibration absorbing body 64 are provided. The various components are secured together, for example by an adhesive.

The nozzle plate 62 is a plate-like member in which a plurality of nozzles N are formed. Each of the plurality of nozzles N is a circular through-hole through which ink passes. The nozzle plate 62 of the first embodiment is formed with a plurality of nozzles N constituting the first row L1 and a plurality of nozzles N constituting the second row L2. The nozzle plate 62 is manufactured by processing a single crystal substrate of silicon (Si) by, for example, a semiconductor manufacturing technique (a processing technique such as dry etching or wet etching). However, any known material or manufacturing method can be used for manufacturing the nozzle plate 62.

As illustrated in fig. 2 and 3, the channel substrate 32 has an opening 320, a plurality of supply channels 322, a plurality of communication channels 324, and a connection channel 326 formed for each of the first row L1 and the second row L2. The opening 320 is an elongated opening formed along the X direction in a plan view (i.e., in a Z direction), and the supply flow path 322 and the communication flow path 324 are through holes formed for each nozzle N. The connection flow path 326 is an elongated space formed along the X direction across the plurality of nozzles N, and communicates the opening 320 and the plurality of supply flow paths 322 with each other. Each of the plurality of communication flow passages 324 overlaps one nozzle N corresponding to the communication flow passage 324 in a plan view.

As illustrated in fig. 2 and 3, the pressure chamber substrate 34 is a plate-shaped member in which a plurality of pressure chambers 342 are formed for each of the first row L1 and the second row L2. The plurality of pressure chambers 342 are arranged in the X direction. Each pressure chamber 342 (cavity) is an elongated space formed for each nozzle N and extending in the Y direction in a plan view. The flow path substrate 32 and the pressure chamber substrate 34 are manufactured by processing a silicon single crystal substrate by, for example, a semiconductor manufacturing technique, in the same manner as the nozzle plate 62 described above. However, any known material or manufacturing method may be used for manufacturing the flow path substrate 32 and the pressure chamber substrate 34.

As illustrated in fig. 2, a vibration plate 42 is formed on the surface of the pressure chamber substrate 34 on the opposite side to the flow path substrate 32. The diaphragm 42 of the first embodiment is a plate-shaped member capable of elastic vibration. Further, a part or the whole of the vibration plate 42 may be formed integrally with the pressure chamber substrate 34 by selectively removing a part in the plate thickness direction with respect to a region corresponding to the pressure chamber 342 in the plate-shaped member having a predetermined plate thickness.

As understood from fig. 3, the pressure chamber 342 is a space between the flow path substrate 32 and the vibration plate 42. The plurality of pressure chambers 342 are arranged in the X direction for each of the first row L1 and the second row L2. As illustrated in fig. 2 and 3, the pressure chamber 342 communicates with the communication flow passage 324 and the supply flow passage 322. Therefore, the pressure chamber 342 communicates with the nozzle N through the communication flow passage 324, and communicates with the opening 320 through the supply flow passage 322 and the connection flow passage 326.

As illustrated in fig. 2 and 3, the piezoelectric element 44 is located on the surface of the flow channel structure 30 opposite to the nozzle N. Specifically, on the surface of the diaphragm 42 of the flow channel structure 30 on the side opposite to the pressure chambers 342, a plurality of piezoelectric elements 44 corresponding to different nozzles N are formed for each of the first row L1 and the second row L2. Each piezoelectric element 44 is a driven element that is deformed by a drive signal D supplied from the drive circuit 80 to change the pressure in the pressure chamber 342. The drive signal D output from the drive circuit 80 is supplied to each piezoelectric element 44 via the connection terminal T of the first wiring board 46. The drive circuit 80 is supplied with a drive signal D from the control unit 20 via the second wiring board 613.

The drive circuit 80 includes a plurality of switches corresponding to different piezoelectric elements 44, and controls whether or not to supply the drive pulse P of the drive signal D to the piezoelectric element 44 for each piezoelectric element 44 based on the control signal S. Specifically, the drive circuit 80 supplies the drive pulse P to the piezoelectric element 44 corresponding to the nozzle N from which the control signal S instructs ejection of ink, and does not supply the drive pulse P to the piezoelectric element 44 corresponding to the nozzle N from which the control signal S instructs non-ejection of ink.

The first wiring board 46 in fig. 2 is a plate-like member facing the surface of the diaphragm 42 on which the plurality of piezoelectric elements 44 are formed with a gap. That is, the first wiring substrate 46 is located on the opposite side of the flow channel structure 30 as viewed from the piezoelectric element 44. Wiring for electrically connecting the drive circuit 80 and the piezoelectric element 44 is formed on the first wiring substrate 46. The first wiring board 46 of the first embodiment functions as a reinforcing plate for reinforcing the mechanical strength of the liquid ejecting head 261 and a sealing plate for protecting and sealing the piezoelectric element 44.

The first wiring board 46 is electrically connected to the control unit 20 via the second wiring board 613. The second wiring board 613 is a flexible wiring board for supplying various signals and voltages including the drive signal D and the control signal S from the control unit 20 to the first wiring board 46. The end of the second wiring board 613 is bonded to the first wiring board 46. In fig. 2, the positive side end in the X direction of the second wiring substrate 613 is joined to the negative side end in the X direction of the first wiring substrate 46. A connection member such as an FPC (Flexible Printed circuit) or an FFC (Flexible flat cable) is preferably used as the second wiring substrate 613.

The container 48 is a housing for storing ink supplied to the plurality of pressure chambers 342. The surface of the receptacle 48 on the positive side in the Z direction is joined to the flow path substrate 32 with an adhesive, for example. Specifically, the container 48 is a structure in which a liquid storage chamber (reservoir) R that is long in the X direction is formed inside in a plan view. In the first embodiment, the liquid storage chamber R is formed for each of the first row L1 and the second row L2. As illustrated in fig. 3, the liquid retention chamber R includes a first space R1 along the Y direction and a second space R2 along the Z direction when viewed in cross section. The first space R1 in the liquid storage chamber R overlaps the piezoelectric element 44 in a plan view. The second space R2 in the liquid storage chamber R communicates with the opening 320 of the flow path substrate 32. The ink is supplied to the liquid storage chamber R through an inlet 482 formed in the housing 48. The inlet 482 is a tubular portion that communicates the liquid storage chamber R of the container 48 with the outside of the container 48. The ink in the liquid storage chamber R is supplied to the pressure chamber 342 through the connection flow path 326 and the supply flow paths 322. The housing 48 is formed by injection molding of a resin material, for example. In the space formed by the housing 48, the drive circuit 80 is disposed.

The housing 48 of the first embodiment has an opening 484. The opening 484 is formed to be elongated in the X direction so as to overlap the liquid storage chamber R. As illustrated in fig. 2 and 3, the second vibration absorbing body 486 is provided on the upper surface of the housing 48. The second vibration absorbing body 486 is a flexible film that functions as a flexible substrate that absorbs pressure fluctuations of the ink in the liquid storage chamber R, and is provided on the upper surface of the housing 48 so as to close the opening 484, thereby constituting a wall surface of the liquid storage chamber R.

As illustrated in fig. 3, the first vibration absorbing body 64 is an element for absorbing pressure fluctuations of the ink in the liquid storage chamber R. The first vibration absorber 64 of the first embodiment includes an elastic film 641 and a support plate 643. The elastic film 641 is a flexible member formed in a thin film shape. The elastic film 641 of the first embodiment is provided on the surface of the flow path substrate 32 so as to close the opening 320, the supply flow path 322, and the connection flow path 326. The support plate 643 is a flat plate formed of a material having high rigidity such as stainless steel, and supports the elastic film 641 on the surface of the flow path substrate 32 so that the opening formed in the flow path substrate 32 is closed by the elastic film 641. The elastic film 641 deforms in accordance with the pressure of the ink in the storage chamber R, thereby suppressing pressure fluctuations in the liquid storage chamber R.

As illustrated in fig. 2, the second wiring board 613 includes the second base portion 131 and the plurality of second wires 133. The second base portion 131 is a flexible film-like member elongated in the X direction, and has a plurality of second wires 133 formed on a surface thereof facing the first wiring board 46. The plurality of second wires 133 electrically connect the control unit 20 and the first wiring board 46.

Fig. 5 is a block diagram showing a functional configuration of the liquid ejecting apparatus 100. As illustrated in fig. 5, various signals and voltages generated by the control unit 20 are transmitted to the first wiring board 46 through the plurality of second wirings 133. Specifically, the second wiring substrate 613 is provided with a second wiring 133 for supplying the drive signal D and a second wiring 133 for supplying the control signal S. In fig. 5, the second wiring 133 for transmitting a signal or voltage different from the drive signal D and the control signal S is not shown.

As illustrated in fig. 2, the first wiring board 46 includes a first base portion 70 and a plurality of first wirings 72. The first base portion 70 is an insulating plate-like member elongated in the X direction, and is located between the flow channel structure 30 and the drive circuit 80. The first base portion 70 is manufactured by processing a single crystal substrate of silicon by, for example, a semiconductor manufacturing technique. However, any known material or manufacturing method may be used for manufacturing the first base portion 70.

The first base member 70 includes a first surface F1 and a second surface F2 located on opposite sides to each other, and is fixed to the surface of the vibration plate 42 on the opposite side to the flow path substrate 32 with an adhesive, for example. Specifically, the first base portion 70 is provided so that the second surface F2 faces the surface of the diaphragm 42 with a gap therebetween.

A plurality of first wires 72 are formed on the end portion of the first surface F1 of the first base member 70 on the negative side in the X direction. The plurality of first wires 72 electrically connect the second wiring substrate 613 and the drive circuit 80. A plurality of first wirings 72 are formed so as to correspond to the plurality of second wirings 133 of the second wiring substrate 613. The drive signal D and the control signal S supplied from the second wiring board 613 are transmitted to the drive circuit 80 through the plurality of first wirings 72. Specifically, as illustrated in fig. 5, the first wiring board 46 includes a first wiring 72 for supplying the drive signal D and a first wiring 72 for supplying the control signal S.

The head unit 611 and the second wiring substrate 613 are bonded by an adhesive. A Non-Conductive Paste (Non Conductive Paste) is used as the binder. Specifically, the first wiring substrate 46 and the second wiring substrate 613 in the head unit 611 are bonded together. A part (typically, an end part) of each second wiring 133 of the second wiring board 613 functions as a second terminal T2 for supplying the drive signal D and the control signal S to the head unit 611. A part (typically, an end part) of each first wiring 72 of the first wiring board 46 functions as a first terminal T1 to which the drive signal D and the control signal S are supplied. The first surface F1 of the first base 70 functions as a mounting surface on which the first terminals T1 are formed. In a state where the first terminal T1 and the second terminal T2 are electrically connected, the first wiring substrate 46 and the second wiring substrate 613 of the head unit 611 are bonded. Therefore, as illustrated in fig. 5, the drive signal D and the control signal S generated by the control unit 20 are supplied to the drive circuit 80 via the second wiring board 613 and the first wiring board 46.

Fig. 6 is a plan view (left view) and a sectional view (right view) of the second wiring board 613. The second wiring board 613 includes an insulating film 135 covering a part of the second base portion 131. The portion of the second wiring 133 exposed from the periphery of the insulating film 135 is a second terminal T2. As illustrated in fig. 6, the plurality of second terminals T2 are formed in the second base portion 131 so as to be spaced apart by a predetermined interval Oy in the Y direction. The plurality of second terminals T2 are arranged at a pitch M of, for example, 50 μ M or less. The distance between the peripheral edges on the negative side in the Y direction in the two second terminals T2 adjacent to each other is the pitch M. In other words, the pitch M is the sum of the distance Oy between two second terminals T2 adjacent to each other in the Y direction and the width of the second terminal T2.

As illustrated in fig. 6, on the surface of the second terminal T2, a protruding portion E protruding from the surface is formed. In fig. 6, dots are added to the projections E for convenience of explanation. The protruding portion E protrudes from the surface of the second terminal T2 toward the first wiring board 46. The planar shape of the projection E is, for example, a rectangle. In the first embodiment, a plurality of protruding portions E are formed on the surface of the second terminal T2 at predetermined intervals Ox along the X direction in which the second terminal T2 extends. In the first embodiment, the positions of the protruding portions E in the X direction, which the second terminals T2 extend, are the same in two second terminals T2 adjacent to each other in the Y direction. That is, the plurality of protruding portions E corresponding to the plurality of second terminals T2 are arranged in the Y direction. In the first embodiment, the protruding portion E is formed across the entire width of the second terminal T2. That is, the width WE of the protruding portion E is equal to the width WN of the portion other than the protruding portion E in the second terminal T2.

The interval Ox between two projections E adjacent to each other in the X direction among the plurality of projections E formed on the second terminal T2 is larger than the length Lx of the projection E in the X direction to which the second terminal T2 extends (Ox > Lx). In addition, the interval Oy of the two second terminals T2 is larger than the length Lx of the protruding portion E in the X direction in which the second terminals T2 extend (Oy > Lx).

As illustrated in the cross-sectional view of fig. 6, the protruding portion E protrudes at a height Hb that exceeds the surface roughness of the second terminal T2. The surface roughness of the second terminal T2 is, for example, 2 μm or less. The protruding portion E of the first embodiment protrudes at the same height Hb across the entire protruding portion E. That is, the cross-sectional shape of the protruding portion E is rectangular. The height Hb of the projection E is larger than, for example, half the thickness Ha of the second terminal T2 at the projection E (Hb > Ha/2). The thickness Ha of the second terminal T2 is the length from the contact surface with the second base portion 131 to the surface of the protruding portion E in the second terminal T2. The maximum value of the length of the second terminal T2 in the Y direction may also be in other words the thickness of the second terminal T2. Specifically, the thickness Ha of the second terminal T2 is, for example, 9 μm. The height Hb of the protruding portion E is a length from the surface of the portion other than the protruding portion E in the second terminal T2 to the surface of the protruding portion E. Specifically, the height Hb of the protruding portion E is, for example, 6 μm.

Fig. 7 to 9 are cross-sectional views of the first wiring board 46 and the second wiring board 613 in a state of being joined. Fig. 7 is a sectional view taken along line VII-VII of fig. 6, fig. 8 is a sectional view taken along line VIII-VIII of fig. 6, and fig. 9 is a sectional view taken along line IX-IX of fig. 6. That is, fig. 8 is a sectional view of a section of the plurality of second wires 133 passing through the protruding portion E, and fig. 9 is a sectional view of a section of the plurality of second wires 133 except for passing through the protruding portion E.

As illustrated in fig. 7, each of the first wires 72 of the first wiring board 46 is a wire formed by laminating a plurality of conductive layers. As illustrated in fig. 8 and 9, a groove portion along the laminated wiring is formed in the first surface F1 of the first base member 70. The groove portion is a recessed portion having a rectangular cross section recessed from the first surface F1 of the first base portion 70. The first wiring 72 is configured by lamination of a first laminated wiring 721 and a second laminated wiring 722. The first multilayer wiring 721 is a conductive pattern formed of a low-resistance metal such as copper (Cu). As illustrated in fig. 7, the first multilayer wiring 721 is a trench wiring formed inside the groove portion. On the other hand, the second laminated wiring 722 is a conductive pattern covering the first laminated wiring 721. The second laminated wiring 722 covers the first laminated wiring 721 inside the groove portion and is continuous to the first surface F1 of the first base member 70. Specifically, the second laminated wiring 722 is formed by laminating an adhesion layer formed of a metal such as titanium (Ti) or tungsten (W) on the surface of the first laminated wiring 721 and a wiring layer formed of a metal such as gold (Au) on the surface of the adhesion layer. The adhesion layer is a conductive layer for improving adhesion between the first-layer press-fit wire 721 and the wiring layer. The portion of the first wiring 72 facing the second terminal T2 functions as a first terminal T1.

As illustrated in fig. 7 and 8, the surface of the protruding portion E of the second terminal T2 is in contact with the surface of the first terminal T1. That is, the first wiring board 46 and the second wiring board 613 are joined in a state where the first terminal T1 and the second terminal T2 are electrically connected. On the other hand, as illustrated in fig. 9, the portions of the second terminals T2 other than the protruding portions E do not contact the surface of the first terminal T1. The non-conductive paste is interposed between the surface of the portion of the second terminal T2 other than the protruding portion E and the surface of the first terminal T1. The portions of the second terminals T2 other than the protruding portions E may be in contact with the surfaces of the first terminals T1.

In order to electrically connect the terminals to each other using the nonconductive paste, it is necessary to sufficiently closely adhere the surfaces of the terminals to each other. For example, in a structure in which terminals having flat surfaces are joined to each other (hereinafter, referred to as "comparative example"), there is a case in which the terminals do not sufficiently contact each other, resulting in a decrease in reliability of electrical connection between the terminals. The reason why the terminals are not in sufficient contact with each other is presumed to be that the terminals are not in sufficient surface contact with each other due to, for example, irregularities formed on the surfaces of the terminals due to a problem in manufacturing technology. When the terminals are not in sufficient contact with each other, a problem occurs in that a signal is not accurately supplied from one terminal to the other terminal, or a problem occurs in that the terminals generate heat because the contact portion has high resistance. In contrast, in the first embodiment, since the protruding portion E is formed in the second terminal T2, the first terminal T1 and the second terminal T2 are sufficiently closely attached in a state where the protruding portion E is pressed by the first terminal T1 and deformed. Therefore, the reliability of the electrical connection of the first terminal T1 and the second terminal T2 is improved as compared with the comparative example.

According to the structure of the first embodiment in which the plurality of protruding portions E are formed along the X direction in which the second terminal T2 extends, the effect of improving the reliability of the electrical connection between the first terminal T1 and the second terminal T2 is remarkable. In the first embodiment, there is an advantage that since the interval Ox between two mutually adjacent protruding portions E formed on the second terminal T2 is larger than the length Lx of the protruding portion E in the direction in which the second terminal T2 extends, a space for deforming the protruding portion E can be sufficiently secured.

When the distance of the protruding portion E between the two second terminals T2 is short, the protruding portion E may be deformed to cause a short circuit. In the first embodiment, since the interval Oy of the two second terminals T2 adjacent to each other is larger than the length of the protruding portion E in the direction in which the second terminal T2 extends, the distance of the protruding portion E is ensured between the two second terminals T2. Therefore, the possibility of short-circuiting due to deformation of the protruding portion E can be reduced.

Second embodiment

A second embodiment of the present invention will be explained. In the following examples, the same elements as those in the first embodiment in function are denoted by the same reference numerals as those in the first embodiment, and detailed descriptions thereof are omitted as appropriate.

Fig. 10 is a plan view of a second wiring board 613 according to the second embodiment. In the first embodiment, in two mutually adjacent second terminals T2 among the plurality of second terminals T2, the positions of the protruding portions E in the X direction, to which the second terminals T2 extend, are the same. In contrast, as illustrated in fig. 10, in the second embodiment, the position of the protruding portion E in the X direction, in which the second terminal T2 extends, differs between two adjacent second terminals T2 out of the plurality of second terminals T2. Specifically, the protruding portion E of one second terminal T2 is formed at a position corresponding to the interval Ox of the two protruding portions E in the other second terminal T2 in the X direction. Typically, the protrusion E of one second terminal T2 is formed at a position corresponding to the midpoint of the interval Ox in the other second terminal T2. That is, in the arrangement of the plurality of second terminals T2, the positions of the protruding portions E are different in the second terminals T2 located at the even-numbered positions and the second terminals T2 located at the odd-numbered positions.

In the structure in which the positions of the protruding portions E in the direction in which the second terminals T2 extend are the same in the two second terminals T2 adjacent to each other, since the protruding portions E approach due to deformation, a short circuit may occur in the two second terminals T2. In contrast, in the second embodiment, in two adjacent second terminals T2 among the plurality of second terminals T2, the positions of the protruding portions E in the direction in which the second terminals T2 extend are different, and therefore, the distance of the protruding portions E is secured between the two second terminals T2. Therefore, the possibility of short-circuiting due to deformation of the protruding portion E can be reduced.

Third embodiment

Fig. 11 is a plan view of a second wiring board 613 according to the third embodiment. In the first embodiment, the width WE of the protruding portion E is equal to the width WN of the portion other than the protruding portion E in the second terminal T2. In contrast, as illustrated in fig. 11, in the third embodiment, the width WE of the protruding portion E is smaller than the width WN of the portion other than the protruding portion E of the second terminal T2. That is, the peripheral edge of the protruding portion E in the X direction is located inward of the peripheral edge of the portion of the second terminal T2 other than the protruding portion E in the X direction.

According to the structure of the third embodiment, the distance of the protruding portion E is ensured between the adjacent two second terminals T2. Therefore, the possibility of short-circuiting due to deformation of the protruding portion E can be reduced. The configuration of the third embodiment can also be applied to the configuration of the second embodiment.

Modification example

The above-described embodiments can be variously modified. Specific modifications that can be applied to the above-described embodiments will be exemplified below. Two or more modes arbitrarily selected from the following examples can be appropriately combined within a range not contradictory to each other.

(1) In each of the above embodiments, the first surface F1 of the first base body 70 is exemplified as the mounting surface on which the first terminals T1 are formed, but the surface of a different element from the first base body 70 in the head unit 611 may be the mounting surface. For example, in a configuration in which wiring connected to the electrodes of the piezoelectric element 44 is formed on the surface of the diaphragm 42, the second wiring substrate 613 is bonded to the surface of the diaphragm 42 as a mounting surface. That is, the element of the head unit 611 bonded to the second wiring substrate 613 with the adhesive is not limited to the first wiring substrate 46.

(2) In each of the above embodiments, the height Hb of the protruding portion E is illustrated as being larger than half the thickness Ha of the second terminal T2 at the protruding portion E, but the height Hb of the protruding portion E may be any height as long as it protrudes at a height exceeding the surface roughness of the second terminal T2.

(3) Although the foregoing embodiments have exemplified the structure in which the interval Ox between two projections E adjacent to each other in the X direction among the plurality of projections E formed in the second terminal T2 is larger than the length Lx of the projections E in the direction in which the second terminal T2 extends, the interval Ox may be smaller than the length Lx of the projections E.

(4) In each of the above embodiments, the configuration in which the distance Oy of the two second terminals T2 is larger than the length Lx of the protruding portion E in the direction in which the second terminals T2 extend has been illustrated, but the distance Oy may be smaller than the length Lx of the protruding portion E.

(5) In each of the above embodiments, the cross-sectional shape of the protruding portion E is rectangular, but the cross-sectional shape of the protruding portion E may be trapezoidal or triangular, for example. That is, the protrusion E may not protrude at the same height Hb over the entire protrusion E.

(6) In the above-described embodiments, the protruding portion E having a rectangular planar shape is exemplified, but the planar shape of the protruding portion E is not limited to the above examples. The planar shape of the protruding portion E may be, for example, circular or elliptical.

(7) In each of the above-described embodiments, the width WE of the protruding portion E may be larger than the width WN of the portion other than the protruding portion E of the second terminal T2.

(8) In the second embodiment, in the two second terminals T2 adjacent to each other, as long as the position of the protruding portion E in the direction in which the second terminal T2 extends is different, the position of the protruding portion E is not limited to the configuration illustrated in fig. 10.

(9) Although the line-type liquid ejecting apparatus 100 in which the plurality of nozzles N are distributed over the entire width of the medium 12 has been described as an example in the above embodiment, the present invention can also be applied to a serial-type liquid ejecting apparatus 100 in which a carrier on which the liquid ejecting head 261 is mounted is reciprocated.

(10) The liquid ejecting apparatus 100 exemplified in the above-described embodiment can be applied to various apparatuses such as a facsimile machine and a copying machine, in addition to the printing-dedicated apparatus. However, the application of the liquid ejecting apparatus 100 of the present invention is not limited to printing. For example, a liquid ejecting apparatus that ejects a solution of a color material is used as an apparatus for manufacturing a color filter of a display device such as a liquid crystal display panel. A liquid ejecting apparatus that ejects a solution of a conductive material is used as a manufacturing apparatus for forming wiring or electrodes of a wiring board. In addition, a liquid ejecting apparatus that ejects a solution of an organic substance related to a living body is used as a manufacturing apparatus for manufacturing, for example, a biochip.

Description of the symbols

100 … liquid ejection device; 12 … medium; 14 … a liquid container; 20 … control unit; 22 … conveying mechanism; 26 … line head; 261 … liquid jet head; 30 … flow channel structure; 32 … flow channel substrate; 320 … opening part; 322 … supply flow path; 324 … are connected with the flow passage; 326 … is connected with the flow passage; 34 … pressure chamber base plate; 342 … pressure chamber; 42 … diaphragm; 44 … piezoelectric element; 46 … wiring board; a 48 … receiver; 482 … introduction port; 484 … opening parts; 486 … second vibration absorber; 611 … head element; 613 … second wiring board; 131 … a second base portion; 133 … second wiring; 135 … insulating film; 62 … a nozzle plate; 64 … first vibration absorber; 641 … an elastic film; 643 … supporting a plate; 661 … head unit; 70 … a first base portion; 72 … first wiring; 721 … first laminated wiring; 722 … second laminated wiring; 80 … drive the circuit.