JP2010234553A - Driving unit and manufacturing method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To stably maintain an electric connection state between a connection bump and a connection terminal. <P>SOLUTION: An ink ejecting unit 10 functioning as a driving unit is provided with: an actuator 18 having a terminal part 36b formed on the surface of the actuator body 18a; a wired substrate 20 having a second connection terminal 58 formed facing the terminal part 36b, on the surface of the substrate body 52; the connection bump 42 integrally formed with the terminal part 36b, and which is contacted with the second connection terminal 58 in a state where the bump is crushed between the terminal part 36b and the second connection terminal 58; an inspection bump 44 integrally formed with the actuator 18; an inspection pressing part 60 formed facing the inspection bump 44, on the wired substrate 20; and a pair of inspection terminals 40a and 40b formed on the actuator 18 and the wired substrate 20, respectively. The pair of inspection terminals 40a and 40b are arranged so as to establish a positional relationship where the terminals 40a and 40b electrically connect to each other when the inspection bump 44 is pushed against an inspection pressing part 60 and crushed. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a drive unit configured by electrically connecting a drive device and a wiring board via bumps, and a manufacturing method thereof.

  As a conventional drive unit including a drive device and a wiring board, for example, an ink discharge unit is well known, and an example thereof is disclosed in Patent Document 1. The ink ejection unit of Patent Document 1 includes an actuator having a plurality of drive units that selectively eject ink from a plurality of nozzles based on a drive signal supplied from a driver IC or the like, a sheet-like substrate body, and a surface thereof. A wiring board having a plurality of formed wirings, and a plurality of first connection terminals that are respectively connected to the plurality of driving units are formed on the surface of the actuator, and the surface of the wiring board is formed on the surface of the wiring board. A plurality of second connection terminals that are electrically connected to the plurality of wirings are formed. In the actuator, connection bumps are integrally formed on the surface of the first connection terminal. In the wiring board, the wiring and the second connection terminal are covered with a synthetic resin layer formed on the surface of the substrate body. ing. Then, the connection bump penetrates the uncured synthetic resin layer and is pressed against the second connection terminal, so that the connection bump and the second connection terminal are electrically connected, and the composite adhered to the surface of the connection bump. As the resin layer is cured, the connection bump and the second connection terminal are physically connected.

JP 2005-305847 A

  In the conventional ink discharge unit (Patent Document 1), the connection bumps are pressed against the second connection terminals and crushed, thereby ensuring a contact area between the connection bumps and the second connection terminals and electrically connecting them. However, since there was no means for suitably adjusting the degree of crushing of the connection bump, when the contact area between the connection bump and the second connection terminal is small, the electrical The connection state could not be stably maintained. For example, when moisture permeates the contact portion between the connection bump and the second connection terminal, the contact portion is corroded to increase the electrical resistance of the contact portion, but the connection bump and the second connection terminal When the contact area is small, the influence of the increased electrical resistance is significant, and there is a risk of causing an electrical connection failure. In other words, when the contact area between the connection bump and the second connection terminal is small, even if the conductivity at these contact portions is appropriate at the time of manufacture, there is a possibility that it may be easily impaired by subsequent corrosion, etc. The reliability for the continuity could not be obtained.

  The present invention has been made to solve the above-described problems, and provides a drive unit and a method for manufacturing the same that can stably maintain an electrical connection state between a connection bump and a second connection terminal. For the purpose.

  In order to solve the above-described problems, a drive unit according to the present invention is formed to face a drive device having a drive unit, a first connection terminal electrically connected to the drive unit, and the first connection terminal. A wiring board having a second connection terminal and a wiring electrically connected to the second connection terminal; and formed integrally with either the first connection terminal or the second connection terminal; A connection bump for electrically connecting the first connection terminal and the second connection terminal by being brought into contact with the other in a state of being crushed between the one connection terminal and the second connection terminal; Inspection bumps integrally formed on any one of the wiring boards, inspection pressing portions formed on the other side of the driving device and the wiring board so as to face the inspection bumps, the driving devices, and the Each of the wiring boards Or a pair of inspection terminals formed on either one of the driving device and the wiring board so as to be spaced apart from each other, the pair of inspection terminals being the inspection pushing They are arranged so as to be in a positional relationship in which they are electrically connected to each other by the inspection bumps pressed against and pressed by the parts.

  In this configuration, since both the connection bumps and the inspection bumps are disposed between the driving device and the wiring board, the driving device and the wiring board are relatively moved toward each other during manufacturing. As a result, the connection bump and the inspection bump are simultaneously crushed. Then, when the connection bump and the inspection bump are crushed to a predetermined degree, the pair of inspection terminals are electrically connected by the inspection bump. Therefore, by designing the “material”, “height”, etc. of the connection bump and the inspection bump so that the pair of inspection terminals are electrically connected when the connection bump is suitably crushed, Whether or not the connection bumps are suitably crushed can be determined simply by electrically detecting whether or not the pair of inspection terminals are electrically connected.

  In order to solve the above problems, a method of manufacturing a drive device according to the present invention includes a drive device having a drive unit and a first connection terminal electrically connected to the drive unit, and is opposed to the first connection terminal. Formed integrally with any one of the first connection terminal and the second connection terminal, the wiring board having the second connection terminal formed in this way, and the wiring electrically connected to the second connection terminal. A connection bump for electrically connecting the first connection terminal and the second connection terminal by being brought into contact with the other in a state of being crushed between the first connection terminal and the second connection terminal; Inspection bumps integrally formed on one of the driving device and the wiring substrate, an inspection pressing portion formed on the other of the driving device and the wiring substrate so as to face the inspection bump, and the driving Apparatus and wiring board A pair of inspection terminals formed separately on each of the drive device and the wiring board, and the pair of inspection terminals, the pair of inspection terminals, A method of manufacturing a drive unit, wherein the drive unit is disposed so as to be in a positional relationship of being electrically connected to each other by the inspection bumps pressed against and pressed by the pressing unit, (a) the drive device And forming each of the connection bump, the inspection bump, the inspection pressing portion, and the pair of inspection terminals on a predetermined portion of the wiring board, and (b) making the driving device and the wiring board face each other. Accordingly, the connection bump is disposed between the first connection terminal and the second connection terminal, and the inspection bump is disposed on the predetermined portion of the driving device and the predetermined portion of the wiring board. And (c) simultaneously moving the connection bump and the inspection bump with the same pressure by moving the driving device and the wiring board relatively close to each other. A step of crushing and electrically connecting the pair of inspection terminals with the crushed inspection bump; and (d) electrical characteristics of a crushing inspection circuit configured by the pair of inspection terminals and the inspection bump. Measuring.

  The present invention has been made in order to solve the above-described problems. By electrically detecting “whether or not a pair of inspection terminals are electrically connected”, the “inspection bump is suitably crushed”. It is possible to detect “whether or not the connection bump is suitably crushed” based on the detection result, and “the contact area between the connection bump and the second connection terminal”. Can be determined. Therefore, the reliability with respect to the electrical connection state between the connection bump and the second connection terminal can be increased, and the electrical connection state can be stably maintained.

FIG. 3 is an exploded perspective view illustrating a configuration of an ink discharge unit according to the embodiment. It is a fragmentary sectional view showing the composition of the ink discharge unit concerning an embodiment. FIG. 4 is a partially enlarged plan view showing a configuration of an actuator in the ink discharge unit. It is a top view which shows the structure of the wiring board in the ink discharge unit which concerns on embodiment. It is a figure which shows the structure of the "wiring board connection structure" and the "crushing inspection circuit" in the ink discharge unit which concerns on embodiment, (A) is a 2nd connection terminal, a test pressing part, and a 2nd test terminal It is a top view which shows the structure of (B), (B) is a partial expanded sectional view. FIG. 5 is a circuit diagram illustrating a configuration of a “crush inspection circuit” in the ink ejection unit according to the embodiment. It is process drawing which shows the process of the manufacturing method of the ink discharge unit which concerns on embodiment in steps. It is a top view which shows the 1st modification of the terminal for a test | inspection. It is a top view which shows the 2nd modification of the terminal for a test | inspection. It is a top view which shows the 3rd modification of the terminal for a test | inspection. It is a top view which shows the 3rd modification of the terminal for a test | inspection. It is a top view which shows the 5th modification of the inspection terminal, (A) is a top view which shows the composition of the 2nd connection terminal, the inspection pressing part, and the 2nd inspection terminal, (B) It is a partial expanded sectional view.

  Hereinafter, a “driving unit” and a “driving unit manufacturing method” according to a preferred embodiment of the present invention will be described with reference to the drawings. In the following embodiments, the present invention is applied to an “ink ejection unit” that ejects ink using an “actuator”. However, the present invention applies pressure when heated by a “heating element”. To other “drive units” such as “ink discharge unit” for discharging ink, “colored liquid discharge unit” for discharging colored liquid, “conductive liquid discharge unit” for discharging conductive liquid, etc. Is also applicable. When the present invention is applied to a “colored liquid discharge unit” or “conductive liquid discharge unit” or the like, “ink” used in the following description is read as “colored liquid” or “conductive liquid” or the like. Further, “lower” used in the following description means the direction in which ink is ejected, and “upper” means the opposite direction.

[Overall configuration of ink discharge unit]
FIG. 1 is an exploded perspective view showing the configuration of the ink discharge unit 10. The ink discharge unit 10 includes a plurality of nozzles 14 (based on driving signals supplied from two driver ICs 12 for black (BK), yellow (Y), cyan (C), and magenta (M). As shown in FIG. 1, a flow path unit 16, an actuator 18 as a “driving device”, and wiring are selectively discharged from a discharge target (not shown) such as paper from FIG. And a substrate 20.

<Flow path unit>
As shown in FIG. 2, the flow path unit 16 is configured by stacking five plates 22 a to 22 e, and “concave portions” or “through holes” formed in these plates 22 a to 22 e are mutually connected. By communicating, four ink flow paths N1 to N4 (FIG. 1) are configured for each ink color. That is, the flow path unit 16 includes a manifold 24 for collecting ink, an ink supply port 26 (FIG. 1) for supplying ink to the manifold 24, a plurality of nozzles 14 for discharging ink in the manifold 24 to the outside, and a manifold. 24 and a plurality of individual channels 28 that communicate with the plurality of nozzles 14 are configured for each ink color, and each of the plurality of individual channels 28 has a pressure chamber that communicates with the nozzle 14 individually. 30 is provided.

  On the nozzle surface 16a where the plurality of nozzles 14 in the ink discharge unit 10 are formed, as shown in FIG. 3, the plurality of nozzles 14 constituting each of the ink flow paths N1 to N4 (FIG. 1) are arranged in a line. A nozzle cap (not shown) is disposed between a region where a plurality of nozzles 14 for discharging black (BK) ink is formed and a region where a plurality of nozzles 14 for discharging other ink are formed. The strip-shaped cap contact region Q with which the partition wall (not shown) is contacted is secured. As shown in FIG. 3, a first inspection terminal 40a and an inspection bump 44, which will be described later, are located at positions corresponding to the cap contact area Q on the surface of the actuator body 18a from the viewpoint of effectively utilizing the empty area. Is formed.

<Actuator>
As shown in FIG. 2, the actuator 18 constitutes the upper surface 30 a of the pressure chamber 30 in the flow path unit 16 and selectively applies ejection pressure to the ink existing in each of the plurality of pressure chambers 30. The diaphragm 32, the piezoelectric layer 34, the plurality of individual electrodes 36, at least one (a plurality in the present embodiment) common electrode terminal 38 (FIG. 3), and at least one first inspection terminal 40a. The individual electrode 36, the common electrode terminal 38, and the first inspection terminal 40 a are formed on the surface of the actuator body 18 a configured by laminating the diaphragm 32 and the piezoelectric layer 34. .

  The diaphragm 32 is formed in a sheet shape from a conductive material, and is joined to the upper surface of the flow path unit 16 so as to cover the plurality of pressure chambers 30. The piezoelectric layer 34 is formed in a sheet shape from a piezoelectric material mainly composed of lead zirconate titanate (PZT), and is polarized in the thickness direction. As shown in FIG. 3, the individual electrode 36 includes an electrode portion 36 a made of a conductive material, and a terminal portion 36 b as a “first connection terminal” made of a conductive material and connected to the electrode portion 36 a. The electrode portion 36a is formed at a position corresponding to the pressure chamber 30 (FIG. 2) on the surface of the actuator body 18a, and the terminal portion 36b is from a position corresponding to the pressure chamber 30 on the surface of the actuator body 18a. It is formed at a position away from it. And the connection bump 42 (FIG. 5) which has electroconductivity is integrally formed in the surface of the terminal part 36b. As shown in FIG. 3, the common electrode terminal 38 is formed in a band shape with a conductive material outside the region where the plurality of individual electrodes 36 are formed on the surface of the actuator body 18 a, and is formed on the surface of the common electrode terminal 38. A plurality of connection bumps 42 having conductivity are integrally formed.

  As shown in FIG. 3, the first inspection terminal 40a has the same hardness as that of the terminal portion 36b as the “first connection terminal” at a position corresponding to the cap contact region Q on the surface of the actuator body 18a. The test bump 44 having conductivity for electrically connecting the first test terminal 40a and a second test terminal 40b to be described later is formed on the surface of the first test terminal 40a. (FIG. 5) is integrally formed. That is, the first inspection terminal 40a functions as a “terminal” for electrical connection, and functions as an “inspection bump placement portion” for disposing the inspection bumps 44 on the surface of the actuator body 18a. And have both.

  As shown in FIG. 2, the common electrode terminal 38 (FIG. 3), the first inspection terminal 40a, and the diaphragm 32 are electrically connected through the conductive portion 46 provided through the piezoelectric layer 34. The common electrode terminal 38 (FIG. 3) is connected to the ground potential (0 V) via the ground wiring 57 (FIGS. 4 and 6) of the wiring board 20. Therefore, in the actuator 18, the diaphragm 32 is a “common electrode” corresponding to the individual electrode 36, and a portion of the piezoelectric layer 34 sandwiched between the diaphragm 32 and the electrode portion 36 a is driven by the drive voltage. This is a drive unit 48.

  As shown in FIG. 5, each of the plurality of connection bumps 42 is a protrusion-like member formed in a substantially truncated cone shape or a substantially hemispherical shape with a conductive material (a metal material containing Ag or the like). The surface of is formed in an inclined surface that spreads outward as it goes from the top part 42a to the base end part 42b. The base end portion 42b of the connection bump 42 is integrally formed with the terminal portion 36b as the “first connection terminal” and is electrically connected to the corresponding electrode portion 36a, and the top portion 42a of the connection bump 42 is The insulating coating material 62, which will be described later, penetrates and is pressed against the corresponding second connection terminal 58, whereby the individual electrode 36, the connection bump 42, and the second connection terminal 58 are electrically connected. The thickness of the insulating coating material 62 to be described later is about 15 to 20 μm, whereas the height of the connection bump 42 before crushing is designed to be about 35 μm.

  As shown in FIG. 5, the inspection bump 44 is a protrusion-like member formed in a substantially truncated cone shape or a substantially hemispherical shape by the same conductive material (such as a metal material containing Ag) as the connection bump 42. The surface of the bump 44 is formed in an inclined surface that spreads outward as it goes from the top 44a to the base end 44b. The base end portion 44b of the inspection bump 44 is formed integrally with the first inspection terminal 40a functioning as the “inspection bump placement portion” and the diaphragm 32 (FIG. 2) via the conductive portion 46. In addition, the top 44a of the inspection bump 44 penetrates the insulating coating material 62 and is pressed against the inspection pressing portion 60 described later, and physically and electrically to the second inspection terminal 40b. It is connected. The height of the inspection bumps 44 before crushing is designed to be about 35 μm like the connection bumps 42.

  In the present embodiment, the terminal portion 36b of the individual electrode 36 is the “first connection terminal”, but the specific configuration of the “first connection terminal” may be changed as appropriate. For example, when the individual electrode 36 is formed on the intermediate layer (piezoelectric layer) of the actuator body 18a, an individual electrode terminal (not shown) as a “first connection terminal” is formed on the surface of the actuator body 18a. You may electrically connect the said individual electrode terminal and the terminal part 36b of the individual electrode 36 via the electroconductive part (illustration omitted) provided in the inside of the actuator main body 18a.

  In the present embodiment, the connection bumps 42 are formed on the terminal portions 36b of the actuator 18 and the inspection bumps 44 are formed on the first inspection terminals 40a of the actuator 18, but the connection bumps 42 are formed on the wiring board 20. The inspection bumps 44 may be formed in the vicinity of the first inspection terminals 40 a in the actuator 18. Further, the inspection bumps 44 may be formed on the second inspection terminals 40b of the wiring board 20, or may be formed in the vicinity of the second inspection terminals 40b on the wiring board 20. When the inspection bumps 44 are formed on the wiring board 20 side, an inspection pressing portion 60 described later is formed on a predetermined portion of the actuator 18 so as to face the inspection bumps 44.

<Wiring board>
As shown in FIG. 4, the wiring substrate 20 is mounted on a sheet-like substrate body 52 made of a synthetic resin material having flexibility and insulation, such as polyimide resin, and one surface of the substrate body 52. Two driver ICs 12 (FIGS. 1 and 4), one end of which is electrically connected to an output terminal (not shown) of the driver IC 12, a plurality of driving wirings 54 for outputting a driving voltage, and an output of the driver IC 12 At least one inspection wiring 56 (one in this embodiment) is electrically connected to a terminal (not shown) and outputs an inspection voltage, and one end is connected to a ground potential. Wiring 57 is provided. In addition, as shown in FIG. 5, the wiring board 20 is electrically connected to the other ends of the plurality of drive wirings 54 and is formed with a plurality of second terminals formed facing the terminal portions 36 b. The inspection terminal 60 is electrically connected to the other end of the connection terminal 58, the inspection pressing part 60 formed on one surface of the substrate body 52 so as to face the inspection bump 44, and the inspection pressing part 60. And the second inspection terminal 40b formed at a distance from the inspection pressing portion 60 and on one surface of the substrate body 52, the drive wiring 54, the inspection wiring 56, the second connection terminal 58, and the inspection It has the insulation coating material 62 which coat | covers the press part 60 and the 2nd test | inspection terminal 40b.

  The second connection terminal 58 is a portion against which the top portion 42a of the connection bump 42 is pressed when the connection bump 42 is crushed, and the second connection terminal 58 is omitted in plan view by a material that is physically harder than the connection bump 42 (such as carbon). It is formed in a circle. As shown in FIG. 5, the contact point P <b> 1 against which the top portion 42 a of the second connection terminal 58 is pressed is located at the center of the second connection terminal 58. Therefore, when the connection bump 42 is crushed, the top portion 42a does not protrude from the second connection terminal 58, and a sufficiently wide contact area is secured at the contact portion K between the connection bump 42 and the second connection terminal 58. can do.

  The inspection pressing portion 60 is a portion to which the top portion 44 a of the inspection bump 44 is pressed when the inspection bump 44 is crushed, and is a second connection terminal 58 that is physically harder than the inspection bump 44. The same material (carbon or the like) as that in FIG. As shown in FIG. 5, the contact point P <b> 2 against which the top portion 44 a of the inspection pressing portion 60 is pressed is located at the center of the inspection pressing portion 60. In addition, the diameter of the pressing portion for inspection 60 is designed to be sufficiently smaller than the diameter of the second connection terminal 58. Therefore, when the inspection bump 44 is crushed, the top portion 44a is crushed around the contact point P2, and the outer peripheral portion of the top portion 44a protrudes from the outer peripheral edge of the inspection pressing portion 60. Are physically and electrically connected to the annular second inspection terminal 40b disposed around the periphery of the terminal.

  Since the connection bumps 42 and the inspection bumps 44 are made of the same material, their hardness is the same, and their heights are also the same as described above (about 35 μm). On the other hand, since the 2nd connection terminal 58 and the test press part 60 are formed with the same material, these hardness is the same. Furthermore, as described above, the hardness of the terminal portion 36b and the hardness of the first inspection terminal 40a are the same. Therefore, when the same pressure is applied to the connection bumps 42 and the inspection bumps 44 between the actuator 18 and the wiring board 20, the connection bumps 42 and the inspection bumps 44 approximate the degree of crushing. When the inspection bumps 44 are crushed to a predetermined degree, it can be estimated that the connection bumps 42 are also crushed to the predetermined degree. In addition, as a method of increasing the hardness of each of the second connection terminal 58 and the inspection pressing portion 60, a method of coating with a hard metal or the like may be used.

  The second inspection terminal 40b is a portion that detects that the inspection bump 44 is crushed to a predetermined degree as a pair with the first inspection terminal 40a. It is separated from the part 60 and is formed in an annular shape. When the inspection bump 44 is pressed against the inspection pressing portion 60, the top portion 44a of the inspection bump 44 is crushed around the contact point P2, but when the degree of crushing is small, the outer peripheral portion of the top portion 44a is The inspection bumps 44 do not protrude from the outer peripheral edge of the inspection pressing portion 60, and the inspection bumps 44 and the second inspection terminals 40b are not electrically connected. On the other hand, when the degree of crushing is large, the outer peripheral portion of the top portion 44a protrudes from the outer peripheral edge of the inspection pressing portion 60 and is electrically connected to the second inspection terminal 40b, whereby a pair of inspection terminals 40a, 40b is electrically connected through the inspection bump 44.

  The second inspection terminal 40b is arranged apart from each of the first inspection terminal 40a and the inspection pressing portion 60, and is electrically connected to the first inspection terminal 40a by the crushed inspection bump 44. However, the shape of the second inspection terminal 40b is not particularly limited, and may be a circular shape, a band shape, a quadrangular shape, or the like in addition to an annular shape. .

  The insulating coating material 62 is uncured when the plurality of connection bumps 42 penetrate through the ink discharge unit 10 during manufacture, and is cured thereafter, and is a synthetic resin material (epoxy) having thermosetting and electrical insulating properties. Resin). The thickness of the insulating coating 62 is from the viewpoint of effectively exerting the “electrical insulation function” for the drive wiring 54 and the second connection terminal 58 and the “connection function” for connecting the actuator 18 and the wiring board 20. Specifically, the height of the connection bump 42 is about 35 μm, whereas the height is about 15 to 20 μm. As the material of the insulating covering material 62, any material that is uncured when the actuator 18 and the wiring board 20 are connected and is cured after that can be used. Instead of “curable resin”, “ultraviolet curable resin” or the like that is cured by ultraviolet rays may be used.

  In the present embodiment, as described above, the degree of crushing when the same pressure is applied to the connection bumps 42 and the inspection bumps 44 is approximate, and the inspection bumps 44 are collapsed. When this is done, the pair of inspection terminals 40a and 40b are electrically connected, so that it is electrically detected that the inspection terminals 40a and 40b are electrically connected. It can be known that each of them is crushed to the extent that it contacts the inner peripheral edge of the second inspection terminal 40b. Therefore, in the “ink ejection unit manufacturing method” described below, the crushing inspection circuit S electrically detects a state in which the pair of inspection terminals 40a and 40b are electrically connected (hereinafter referred to as “conductive state”). Then, when the conductive state is detected, the operation of crushing the connection bumps 42 is stopped.

[Crush inspection circuit]
As shown in FIG. 5, the crushing inspection circuit S includes a pair of inspection terminals 40a and 40b, inspection bumps 44, and an inspection pressing portion 60. As shown in FIG. 18 internal wirings (including the diaphragm 32), inspection wiring 56 connected to one of the output terminals of the driver IC 12, and driving wiring (VDD2) connected to one of the input terminals of the driver IC 12. 64, an ammeter 66 as a “measurement device” connected in series to the drive wiring (VDD2) 64, and a ground wiring 57 connected to the ground potential. The drive wiring (VDD2) 64 and the ground wiring 57 are for applying a drive voltage to the drive unit 48 of the actuator 18 during a normal ink discharge operation, but when detecting a conduction state. Is used to apply an inspection voltage between the pair of inspection terminals 40a and 40b. In the crushing inspection circuit S, when the pair of inspection terminals 40a and 40b are not electrically connected by the inspection bump 44, the current flowing through the drive wiring (VDD2) 64 is small and the output of the ammeter 66 is small. When the pair of inspection terminals 40a and 40b are electrically connected by the crushed inspection bumps 44, the current flowing through the drive wiring (VDD2) 64 increases and the output of the ammeter 66 also increases. Therefore, the conduction state can be detected based on the output change of the ammeter 66, and it can be estimated that the connection bump 42 and the second connection terminal 58 are in contact with each other with a predetermined area.

In order to detect the conduction state, it is necessary to measure the electrical characteristics of the crushing inspection circuit S. However, the measurement object is not particularly limited, and the resistance, impedance, etc. are measured in addition to the current. May be. When changing the measurement target, instead of the ammeter 66, another “measurement device” corresponding to the measurement target is used.
[Manufacturing method of ink discharge unit]
FIG. 7 is a process diagram showing the steps of the method for manufacturing the ink discharge unit 10 step by step. When the ink discharge unit 10 is manufactured, the “bump forming process”, “positioning process”, “crushing / measuring process”, and “curing process” are executed in this order.

  In the “bump formation process”, connection bumps 42, inspection bumps 44, inspection pressing portions 60, and a pair of inspection terminals 40a and 40b are formed on predetermined portions of the actuator 18 and the wiring board 20, respectively. In this step, in order to bring the connection bump 42 and the second connection terminal 58 into contact with each other with a suitable contact area, it is particularly necessary to improve the positional accuracy of the inspection bump 44 and the pair of inspection terminals 40a and 40b.

  In the “positioning step”, as shown in FIG. 7A, first, an uncured insulating coating material 62 is applied to the surface of the substrate body 52 in the wiring substrate 20, and the driving wiring 54 ( 5), the inspection wiring 56 (FIG. 5), the second connection terminal 58, the inspection pressing portion 60, and the second inspection terminal 40b are covered. Then, by facing the actuator 18 and the wiring board 20, the connection bumps 42 are disposed between the terminal portions 36 b and the second connection terminals 58, and the inspection bumps 44 are arranged on predetermined portions of the actuator 18 (this embodiment). Then, it arrange | positions between the predetermined part (In this embodiment, the test press part 60) of the 1st test | inspection terminal 40a) and the wiring board 20. FIG.

  In the “crushing / measuring step”, as shown in FIG. 7B, the actuator 18 and the wiring board 20 are relatively moved in a direction approaching each other, whereby the connection bumps 42 and the inspection bumps 44 are moved to the first. 2 Pressing against each of the connection terminal 58 and the inspection pressing part 60, the connection bump 42 and the inspection bump 44 are simultaneously crushed with the same pressure, and the pair of inspection terminals 40a and 40b are crushed. Conduction is made by the bumps 44 for use. Further, the conduction state between the pair of inspection terminals 40a and 40b is continuously detected by using the above-described crushing inspection circuit S (FIG. 6). That is, by driving the driver IC 12, a test voltage is applied between the pair of test terminals 40 a and 40 b, and the value of the current flowing through the drive wiring (VDD 2) 64 is continuously read by the ammeter 66. Then, when the conduction state is detected based on the output of the ammeter 66, the operation of crushing the connection bumps 42 and the inspection bumps 44 is stopped.

  In the “curing step”, as shown in FIG. 7C, the uncured insulating coating material 62 is heated (for example, 150 ° C.) to cure the insulating coating material 62. In the previous “crushing / measurement step”, the uncured insulating coating material 62 pushed away at the top 42 a of the connection bump 42 adheres to the surface of the connection bump 42, and is not pushed away at the top 44 a of the inspection bump 44. Since the cured insulation coating material 62 adheres to the surface of the inspection bump 44, after the insulation coating material 62 is cured, the insulation coating material 62 attached to the respective surfaces of the connection bump 42 and the inspection bump 44 is applied to the actuator 18. And a function of connecting the wiring board 20 to each other. The “curing step” differs depending on the type of the insulating coating material 62. When an ultraviolet curable resin is used as the insulating coating material 62, the insulating coating material 62 is irradiated with ultraviolet rays.

  In this embodiment, the conduction state between the pair of inspection terminals 40a and 40b is detected in the “crushing / measurement process”, but the conduction state is detected after the “curing process”. May be.

[First Modification of Inspection Terminal]
As shown in FIG. 8, the first modification of the inspection terminal includes two inspection terminals 70b arranged on both sides of the inspection pressing portion 60, and an inspection for each of the two inspection terminals 70b. The wiring 56 is connected, and other configurations are the same as in the above-described embodiment. That is, in the first modification, the pair of inspection terminals 70b and 70b that are electrically connected by the crushed inspection bump 44 are both formed on the wiring board 20, and the inspection pressing portion 60 is The first inspection terminal 40a, which is provided in the middle portion of the pair of inspection terminals 70b, 70b on the wiring board 20, and is different from the pair of inspection terminals 70b, 70b, is electrically connected to the inspection bump 44. Being
In this configuration, “one inspection terminal 70b and the first inspection terminal 40a”, “the other inspection terminal 70b and the first inspection terminal 40a”, “one inspection terminal 70a and the other inspection terminal 70b”. ”Constitutes“ a pair of inspection terminals ”that are electrically connected (conducted) by the inspection bumps 44, so that“ one inspection terminal 70 b and the first inspection terminal 40 a are connected to each other ”. "The first conduction state in which the other inspection terminal 70b and the first inspection terminal 40a are conducted" and "both the inspection terminal 70b and the first inspection terminal 40a. It is possible to detect the “third conduction state in which the conductor is conducted”, and based on the detection results, “the presence / absence of displacement” and “the direction of displacement” between the actuator 18 and the wiring board 20. Can detect That. The “number” and “position” of the inspection terminal 70b can be appropriately changed. For example, four inspection terminals 70b may be arranged in a cross shape.

[Second Modification of Inspection Terminal]
As shown in FIG. 9, in the second modification of the inspection terminal, an annular inspection terminal 74b is further arranged outside the annular second inspection terminal 40b disposed around the inspection pressing portion 60. The inspection wiring 56 is connected to each of the second inspection terminal 40b and the inspection terminal 74b, and the other configuration is the same as that of the above-described embodiment.

  In this configuration, since the two crushing inspection circuits S are configured corresponding to the second inspection terminal 40b and the inspection terminal 74b, “the second inspection terminal 40b and the first inspection terminal 40a are connected. In addition to the “conducting conduction state”, it is possible to detect “the conducting state in which the inspection terminal 74b and the first inspection terminal 40a are conducted”. Then, by detecting the latter “conductive state”, it is possible to detect that the inspection bumps 44 have been crushed more than necessary. The “number” of the inspection terminals 74b can be changed as appropriate. For example, the crushing state of the inspection bumps 44 can be detected stepwise by arranging two or more inspection terminals 74b concentrically. Also good.

[Third Modification of Inspection Terminal]
As shown in FIG. 10, in the third modification of the inspection terminal, an annular inspection terminal 78b is provided around the inspection terminal 78a functioning as an “inspection pressing portion”, and the inspection terminal 78a is provided with an inspection terminal 78a. The inspection wiring 56 is connected, and the inspection terminal 78b is connected to the ground potential. The other configuration is the same as that of the above-described embodiment. In this configuration, the crushing inspection circuit S can be easily configured on the wiring board 20 without using the internal wiring (including the diaphragm 32) of the actuator 18.

[Fourth Modification of Inspection Terminal]
As shown in FIG. 11, the fourth modified example of the inspection terminal forms a pair of inspection terminals 80 a and 80 b apart from each other with respect to the wiring board 20 and also forms the inspection pressing portion 60 with the wiring board 20. Are formed at an intermediate portion of the pair of inspection terminals 80a and 80b, the inspection wiring 56 is connected to one inspection terminal 80a, and the other inspection terminal 80b is connected to the ground potential. The configuration is the same as in the above-described embodiment. In this configuration, as in the “third modified example (FIG. 10)”, the crushing inspection circuit S is simply configured on the wiring board 20 without using the internal wiring (including the diaphragm 32) of the actuator 18. Can do. Further, when the inspection bumps 44 pressed and crushed against the inspection pressing portion 60 come into contact with both the pair of inspection terminals 80a and 80b, the pair of inspection terminals 80a and 80b are electrically connected to each other. When the “conductive state” can be detected, it can be estimated that “the inspection bump 44 is located at the center of the inspection pressing portion 60”, and the presence or absence of “positional deviation” can be detected. .

[Fifth Modification of Inspection Terminal]
As shown in FIG. 12, when the inspection terminal 80b formed on the wiring board 20 is connected to the ground potential, the fifth modification of the inspection terminal is connected to the second connection terminal 58 and the inspection terminal 80b. This is connected to the ground potential via the drive unit 48 (FIG. 2) or the like, and other configurations are the same as those in the above-described embodiment. In this configuration, it is not necessary to make a part of the crushing inspection circuit S inside the actuator 18, and the inspection wiring 56 and the driving wiring 54 can be shared, so that the configuration is further simplified. be able to.

  Furthermore, in the above-described embodiment, the inspection bumps 44 are formed separately from the plurality of connection bumps 42, but at least one of the connection bumps 42 may have the function of the inspection bumps 44. .

N1 to N4 ... Ink channel Q ... Contact area S ... Crushing inspection circuit 10 ... Ink discharge unit 14 ... Nozzle 16 ... Channel unit 18 ... Actuator 18a ... Actuator body 20 ... Wiring board 36 ... Individual electrode 36a ... Electrode portion 36b ... Terminal part (first connection terminal)
40a ... first inspection terminal 40b ... second inspection terminal 42 ... connection bump 44 ... inspection bump 48 ... drive section 52 ... substrate body 54 ... drive wiring 56 ... inspection wiring 57 ... ground wiring 58 ... second Connection terminal 60 ... Pushing part 62 for inspection ... Insulation coating material 64 ... Wiring for driving (VDD2)
66 ... Ammeter (measuring device)

Claims (11)

A drive unit having a drive unit and a first connection terminal electrically connected to the drive unit;
A wiring board having a second connection terminal formed opposite to the first connection terminal, and a wiring electrically connected to the second connection terminal;
The first connection terminal is integrally formed with one of the first connection terminal and the second connection terminal, and the first connection terminal is brought into contact with the other while being crushed between the first connection terminal and the second connection terminal. A connection bump for electrically connecting the connection terminal and the second connection terminal;
Bumps for inspection integrally formed on any one of the driving device and the wiring board;
An inspection pressing portion formed on the other side of the driving device and the wiring board so as to face the inspection bump;
A pair of test terminals formed separately on each of the drive device and the wiring board, or formed separately from each other on the drive device and the wiring board;
The pair of inspection terminals are arranged so as to be in a positional relationship in which the pair of inspection terminals are electrically connected to each other by the inspection bumps pressed and crushed against the inspection pressing portion. The inspection bump has the same hardness as the connection bump,
2. The drive unit according to claim 1, wherein the inspection pressing portion has the same hardness as that of the side of the first connection terminal and the second connection terminal on which the connection bump is contacted.   3. The drive unit according to claim 1, wherein the inspection bump is provided to either one of the drive device and the wiring board via an inspection bump placement portion. 4. The pair of inspection terminals are both formed on the wiring board,
The drive unit according to any one of claims 1 to 3, wherein the inspection pressing portion is formed at an intermediate portion of the pair of inspection terminals on the wiring board.   5. The drive unit according to claim 1, wherein any one of the pair of inspection terminals has a function of the inspection pressing portion.   6. The drive unit according to claim 3, wherein any one of the pair of inspection terminals has a function of the inspection bump arrangement portion.   The drive unit according to claim 1, wherein the connection bump has a function of the inspection bump.   The drive unit according to claim 1, wherein the inspection pressing portion is made of a material that is physically harder than the inspection bump.   The drive unit according to any one of claims 1 to 8, further comprising a measuring device that measures electrical characteristics of a crushing inspection circuit configured by the pair of inspection terminals and the inspection bumps. A drive unit having a drive unit and a first connection terminal electrically connected to the drive unit;
A wiring board having a second connection terminal formed opposite to the first connection terminal, and a wiring electrically connected to the second connection terminal;
The first connection terminal is integrally formed with one of the first connection terminal and the second connection terminal, and the first connection terminal is brought into contact with the other while being crushed between the first connection terminal and the second connection terminal. A connection bump for electrically connecting the connection terminal and the second connection terminal;
Bumps for inspection integrally formed on any one of the driving device and the wiring board;
An inspection pressing portion formed on the other side of the driving device and the wiring board so as to face the inspection bump;
A pair of test terminals formed separately on each of the drive device and the wiring board, or formed separately from each other on the drive device and the wiring board;
The pair of inspection terminals are disposed so as to be in a positional relationship in which the pair of inspection terminals are electrically connected to each other by the inspection bumps pressed against and crushed by the inspection pressing portion. Because
(A) forming the connection bump, the inspection bump, the inspection pressing portion, and the pair of inspection terminals on a predetermined portion of the drive device and the wiring board;
(B) By arranging the drive device and the wiring board to face each other, the connection bump is disposed between the first connection terminal and the second connection terminal, and the inspection bump is provided on the drive device in a predetermined manner. Placing between a portion and a predetermined portion of the wiring board;
(C) The connection device and the inspection bump are simultaneously crushed with the same pressure by moving the driving device and the wiring board relatively in a direction approaching each other, and the pair of inspection devices Conducting the terminals with the crushed test bumps;
(D) A method for manufacturing a drive unit, comprising a step of measuring electrical characteristics of a crushing inspection circuit configured by the pair of inspection terminals and the inspection bumps.   The method of manufacturing a drive unit according to claim 10, wherein in the step (a), the connection bump and the inspection bump are formed with the same height using the same material.

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