JP2009255516A - Liquid jetting head, its manufacturing method and liquid jetting apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid jetting head which attains reduction of costs and can easily achieve densification, and to provide its manufacturing method and a liquid jetting apparatus. <P>SOLUTION: The liquid jetting head is equipped with a flow channel forming substrate 10 where pressure generation chambers 12 communicating with nozzle openings 21 for jetting a liquid are formed, pressure generating elements 300, a lead electrode 90 connected to the pressure generating elements 300, a flexible wiring board 410 connected to the lead electrode 90, and a supporting member 400 having the wiring board bonded thereto. A fixation opening 411 penetrating in a thickness direction is formed to the wiring board 410. The wiring board 410 and the supporting member 400 are bonded to each other via an adhesive 420 prepared in the fixation opening 411. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a liquid ejecting head that ejects liquid from a nozzle opening, a manufacturing method thereof, and a liquid ejecting apparatus, and more particularly to an ink jet recording head that ejects ink as a liquid, a manufacturing method thereof, and an ink jet recording apparatus.

  A typical example of a liquid ejecting head that ejects droplets is an ink jet recording head that ejects ink droplets. The ink jet recording head includes, for example, a flow path forming substrate in which a pressure generation chamber communicating with a nozzle opening and a communication portion communicating with the pressure generation chamber are formed, and formed on one surface side of the flow path forming substrate. And a protective substrate having a piezoelectric element holding part for holding the piezoelectric element bonded to the surface of the flow path forming substrate on the piezoelectric element side is known. Here, an IC, which is a drive circuit for driving the piezoelectric element, is placed on the protective substrate. In addition, the drive circuit and the piezoelectric element are connected by a wire bonding method with a connection wiring made of a conductive wire via a lead electrode drawn from one electrode of the piezoelectric element.

  Some protective substrates protect two rows of piezoelectric elements arranged corresponding to two opposite rows of pressure generating chambers, and the connection wiring is inserted into the central portion of this type of protective substrate. A through hole is formed. In such an ink jet recording head, the lead electrode and connection wiring are connected at the through hole portion (see, for example, Patent Document 1).

JP 2004-148813 A

  However, since the drive circuit and the piezoelectric element are connected by the wire bonding method in the above-described prior art, there is a problem that the cost increases and it is difficult to increase the density. In addition, since the drive circuit is arranged in a plane on the protective substrate, the area of the actuator portion including the piezoelectric element is increased, resulting in an increase in cost.

  Such a problem exists not only in an ink jet recording head that ejects ink but also in a liquid ejecting head that ejects liquid other than ink.

  In view of such circumstances, it is an object of the present invention to provide a liquid ejecting head, a manufacturing method thereof, and a liquid ejecting apparatus capable of easily reducing the cost and achieving high density.

According to an aspect of the present invention for solving the above-described problem, a flow path forming substrate in which a pressure generation chamber communicating with a nozzle opening for injecting liquid is formed, and a pressure for injecting liquid into the pressure generation chamber is applied. A pressure generating element formed; a lead electrode connected to the pressure generating element; a flexible wiring board connected to the lead electrode; and a support member bonded to the wiring board. The substrate is provided with a fixing port penetrating in the thickness direction, and the wiring substrate and the support member are bonded to each other through an adhesive provided in the fixing port. It is in.
In this aspect, since the wiring substrate and the lead electrode of the piezoelectric element are connected without using a bonding wire or the like, the manufacturing cost can be easily reduced. Further, since the lower end portion of the wiring board is connected to the lead electrode and is bonded to the side surface of the support member, high density can be easily achieved. Further, by providing the drive circuit on the wiring board, the drive circuit is bonded to the side surface of the support member via the wiring board, so that the heat generated by the drive circuit can be radiated well, and the stable Can contribute to the operation. Further, by bonding the support member and the wiring board via a fixing port provided in the wiring board, the wiring board can be bonded to the plate-like member in a state where the wiring board is positioned with high accuracy, and the lead electrode and the wiring It is possible to prevent poor connection with the substrate.

  Here, it is preferable that a plurality of the fixing ports are provided at predetermined intervals in a region facing the support member in a direction in which the lead electrodes are arranged side by side. According to this, positioning on the lower end side connected to the lead electrode of the wiring board can be performed with high accuracy.

  In addition, a row in which the pressure generating elements are arranged side by side is arranged, the support member is disposed in the side by side arrangement, and the wiring board is bonded to both side surfaces of the support member, The fixing port of the wiring board may be provided at a position facing both side surfaces of the support member. According to this, even if the pressure generating elements are arranged in a plurality of rows, it is possible to achieve a high density as described above and to reduce the manufacturing cost. Further, by providing the fixing port in one wiring board, the wiring board can be bonded to the support member in a state where the relative positioning of both the wiring boards is performed with high accuracy.

  Moreover, it is preferable that the said adhesive consists of an ultraviolet curable adhesive. According to this, it is possible to further shorten the curing time of the adhesive that bonds the wiring board and the support member, and to improve the positioning accuracy of the wiring board.

  Moreover, it is preferable that the wiring board and the lead electrode are electrically connected by conductive particles. According to this, a predetermined electrical connection can be easily achieved simply by pressing and crushing the conductive particles from above.

  Moreover, it is preferable that the buffer member is provided in the lower end surface of the said supporting member. According to this, the conductive particles can be pressed evenly, and a large number of conductive particles corresponding to each lead terminal can be crushed uniformly.

According to still another aspect of the invention, there is provided a liquid ejecting apparatus including the liquid ejecting head according to the above aspect.
In this aspect, the liquid ejecting apparatus can exhibit the individual actions and effects as described above.

  Here, it is preferable that a grounding portion for grounding the support member is provided. According to this, by grounding the support member, noise generated from the drive circuit or the like can be shielded, and inhibition of the drive signal or the like due to noise can be suppressed. Further, by grounding the support member, it is possible to reduce the occurrence of noise due to floating metal when the liquid ejecting head is moved.

According to another aspect of the present invention, a flow path forming substrate in which a pressure generating chamber communicating with a nozzle opening for ejecting liquid is formed, and a pressure for ejecting liquid to the pressure generating chamber is applied. The pressure generating element, a lead electrode connected to the pressure generating element, a flexible wiring board connected to the lead electrode, and a support member bonded to the wiring board. A method of manufacturing a liquid jet head having a substrate provided with a fixing port penetrating in a thickness direction, the step of bonding the wiring substrate to one of the support members, and the wiring substrate to the other of the support members And positioning the other wiring board with respect to one of the wiring boards, and an adhesive for the fixing port provided in the wiring board arranged on the other of the support members. And the support member In the method of manufacturing a liquid jet head characterized by including the step of bonding.
In this aspect, the other wiring board can be bonded to the support member through the fixing port in a state where the other wiring board is positioned with high accuracy, and the lead electrode and each wiring substrate can be connected with high accuracy.

Hereinafter, the present invention will be described in detail based on embodiments.
(Embodiment 1)
FIG. 1 is an exploded perspective view showing a schematic configuration of an ink jet recording head which is an example of a liquid jet head according to Embodiment 1 of the present invention, FIG. 2 is a plan view of FIG. 1, and FIG. FIG. 4 is a side view of FIG. 1 and a BB ′ cross-sectional view thereof.

  As shown in the figure, the flow path forming substrate 10 is made of a silicon single crystal substrate having a plane orientation (110) in this embodiment, and an elastic film 50 made of silicon dioxide is formed on one surface thereof.

  The flow path forming substrate 10 is provided with two rows in which a plurality of pressure generating chambers 12 partitioned by a partition wall 11 are arranged in the width direction. In addition, a communication portion 13 is formed in a region outside the longitudinal direction of the pressure generation chambers 12 in each row, and the communication portion 13 and each pressure generation chamber 12 are provided for each pressure generation chamber 12. The communication path 15 communicates with each other. The communication portion 13 communicates with a reservoir portion 31 of the protective substrate 30 described later and constitutes a part of the reservoir 100 that becomes a common ink chamber for each row of the pressure generating chambers 12. The ink supply path 14 is formed with a narrower width than the pressure generation chamber 12, and maintains a constant flow path resistance of ink flowing into the pressure generation chamber 12 from the communication portion 13. In this embodiment, the ink supply path 14 is formed by narrowing the width of the flow path from one side. However, the ink supply path may be formed by narrowing the width of the flow path from both sides. Further, the ink supply path may be formed by narrowing from the thickness direction instead of narrowing the width of the flow path. Further, each communication passage 15 is formed by extending the partition walls 11 on both sides in the width direction of the pressure generating chamber 12 to the communication portion 13 side to partition the space between the ink supply path 14 and the communication portion 13. Yes. That is, the flow path forming substrate 10 has an ink supply path 14 having a cross-sectional area smaller than the cross-sectional area of the pressure generating chamber 12 in the width direction, and communicates with the ink supply path 14 and disconnects the ink supply path 14 in the width direction. A communication passage 15 having a cross-sectional area larger than the area is provided by being partitioned by a plurality of partition walls 11.

  Further, on the opening surface side of the flow path forming substrate 10, a nozzle plate 20 having a nozzle opening 21 communicating with the vicinity of the end of each pressure generating chamber 12 on the side opposite to the ink supply path 14 is provided with an adhesive. Or a heat-welded film or the like. In this embodiment, since two rows in which the pressure generation chambers 12 are arranged in parallel are provided on the flow path forming substrate 10, one inkjet recording head I has two rows of nozzle rows in which nozzle openings 21 are arranged in parallel. Is provided. The nozzle plate 20 is made of, for example, glass ceramics, a silicon single crystal substrate, or stainless steel.

  On the other hand, the elastic film 50 is formed on the side opposite to the opening surface of the flow path forming substrate 10 as described above, and the insulator film 55 is formed on the elastic film 50. Further, a lower electrode film 60, a piezoelectric layer 70, and an upper electrode film 80 are laminated on the insulator film 55 to constitute the piezoelectric element 300 that is the pressure generating element of this embodiment. Yes. Here, the piezoelectric element 300 refers to a portion including the lower electrode film 60, the piezoelectric layer 70, and the upper electrode film 80. In general, one electrode of the piezoelectric element 300 is used as a common electrode, and the other electrode and the piezoelectric layer 70 are patterned for each pressure generating chamber 12. In addition, here, a portion that is configured by any one of the patterned electrodes and the piezoelectric layer 70 and in which piezoelectric distortion is generated by applying a voltage to both electrodes is referred to as a piezoelectric active portion. In the present embodiment, the lower electrode film 60 is used as a common electrode of the piezoelectric element 300 and the upper electrode film 80 is used as an individual electrode of the piezoelectric element 300. However, there is no problem even if this is reversed for convenience of a drive circuit and wiring. Also, here, the piezoelectric element 300 and the diaphragm that is displaced by driving the piezoelectric element 300 are collectively referred to as an actuator device. In the above-described example, the elastic film 50, the insulator film 55, and the lower electrode film 60 function as a diaphragm. However, the present invention is not limited to this, and for example, the elastic film 50 and the insulator film 55 are provided. Instead, only the lower electrode film 60 may act as a diaphragm. Further, the piezoelectric element 300 itself may substantially serve as a diaphragm.

The piezoelectric layer 70 is made of a piezoelectric material having an electromechanical conversion effect formed on the lower electrode film 60, particularly a ferroelectric material having a perovskite structure among the piezoelectric materials. The piezoelectric layer 70 is preferably a crystal film having a perovskite structure. For example, a ferroelectric material such as lead zirconate titanate (PZT) or a metal oxide such as niobium oxide, nickel oxide, or magnesium oxide is used. Those to which is added are suitable. Specifically, lead titanate (PbTiO ₃ ), lead zirconate titanate (Pb (Zr, Ti) O ₃ ), lead zirconate (PbZrO ₃ ), lead lanthanum titanate ((Pb, La), TiO ₃ ) ) Lead lanthanum zirconate titanate ((Pb, La) (Zr, Ti) O ₃ ) or lead magnesium titanate zirconate titanate (Pb (Zr, Ti) (Mg, Nb) O ₃ ) or the like is used. it can. The piezoelectric layer 70 is formed thick enough to suppress the thickness so as not to generate cracks in the manufacturing process and to exhibit sufficient displacement characteristics.

  In addition, each upper electrode film 80 that is an individual electrode of the piezoelectric element 300 is connected to a lead electrode 90 made of, for example, gold (Au) or the like extending to the insulator film 55. The lead electrode 90 has one end connected to the upper electrode film 80 and the other end extending between the rows where the piezoelectric elements 300 are arranged in parallel.

  Protection having a reservoir portion 31 constituting at least a part of the reservoir 100 on the flow path forming substrate 10 on which the piezoelectric element 300 is formed, that is, on the lower electrode film 60, the elastic film 50 and the lead electrode 90. The substrate 30 is bonded via an adhesive 35. In the present embodiment, the reservoir portion 31 is formed across the protective substrate 30 in the thickness direction and across the width direction of the pressure generating chamber 12, and as described above, the communication portion 13 of the flow path forming substrate 10 is formed. The reservoir 100 is configured as a common ink chamber for the pressure generating chambers 12. In the present embodiment, the flow path forming substrate 10 is provided with the communication portion 13 that becomes the reservoir 100. However, the present invention is not particularly limited thereto. For example, the communication portion 13 of the flow path forming substrate 10 is connected to the pressure generating chamber 12. It is also possible to divide each into a plurality and to use only the reservoir 31 as a reservoir. Further, for example, only the pressure generation chamber 12 is provided on the flow path forming substrate 10, and a reservoir and a member interposed between the flow path forming substrate 10 and the protective substrate 30 (for example, the elastic film 50, the insulator film 55, etc.) An ink supply path 14 that communicates with each pressure generating chamber 12 may be provided.

  Further, a piezoelectric element holding portion 32, which is a holding portion having a space that does not hinder the movement of the piezoelectric element 300, is provided in a region facing the piezoelectric element 300 of the protective substrate 30. The piezoelectric element holding part 32 only needs to have a space that does not hinder the movement of the piezoelectric element 300, and the space may be sealed or unsealed. In this embodiment, since two rows in which the piezoelectric elements 300 are arranged in parallel are provided, the piezoelectric element holding portion 32 is provided corresponding to each row in which the piezoelectric elements 300 are arranged in parallel. . In other words, the protective substrate 30 is provided with two in the direction in which the rows of the piezoelectric elements 300 on which the piezoelectric element holding portions 32 are arranged are arranged.

  As such a protective substrate 30, it is preferable to use substantially the same material as the coefficient of thermal expansion of the flow path forming substrate 10, for example, glass, ceramic material, etc. In this embodiment, the same material as the flow path forming substrate 10 is used. The silicon single crystal substrate was used.

  The protective substrate 30 is provided with a through hole 33 that penetrates the protective substrate 30 in the thickness direction. In the present embodiment, the through hole 33 is provided between the two piezoelectric element holding portions 32. The vicinity of the end portion of the lead electrode 90 drawn from each piezoelectric element 300 is provided so as to be exposed in the through hole 33.

  A COF substrate 410 which is a printed circuit board is used as a kind of flexible wiring board, and a drive circuit 200 for driving the piezoelectric element 300 is mounted on the COF substrate 410. Here, the lower end portion of the COF substrate 410 is connected to the lead electrode 90 and is raised substantially vertically and bonded to the side surface of the plate-like member 400 that is a support member. That is, the plate-like member 400 that is a support member of the present embodiment is a rectangular parallelepiped whose both side surfaces are vertical surfaces. In the present embodiment, the plate member 400, the COF substrate 410, and the drive circuit 200 constitute a wiring board.

  More specifically, in the ink jet recording head I according to the present embodiment, two rows in which the pressure generation chambers 12 are arranged in parallel on the flow path forming substrate 10 are provided, so that the piezoelectric element 300 is arranged in the width direction of the pressure generation chamber 12. Two rows arranged in parallel (in the width direction of the piezoelectric element 300) are provided. That is, two rows of the pressure generating chamber 12, the piezoelectric element 300, and the lead electrode 90 are provided to face each other. The COF substrates 410 are bonded to both side surfaces of the plate-like member 400 whose lower part is inserted into the through-holes 33, and each COF substrate 410 has a lower end portion of each row of the piezoelectric elements 300. It is connected to the end of the lead electrode 90 and is raised almost vertically. In the present embodiment, by providing one COF substrate 410 on each of the side surfaces of the plate-like member 400, a total of two COF substrates 410 are provided on one plate-like member 400.

  The COF substrate 410, which is a flexible printed circuit board, bends even if it is erected as a single unit. Therefore, the COF substrate 410 is bonded to the plate-like member 400, which is a rigid member that supports the COF substrate 410. It is possible to stand up while suppressing the bending of 410.

  In the present embodiment, the rectangular parallelepiped plate-like member 400 is used, but support members having various shapes such as a lattice shape and a hook shape may be used as long as the wiring board can be supported upright.

  Here, as shown in FIG. 4, the COF substrate 410A provided on one side surface of the plate-like member 400 is opposed to the lower end side (side connected to the lead electrode 90) of the side surface of the plate-like member 400. A plurality of fixing ports 411 are provided at predetermined intervals in the direction in which the lead electrodes 90 are arranged in parallel. In the present embodiment, the three fixing ports 411 are provided on the lower end portion side of the COF substrate 410 so as to be equally spaced in the direction in which the lead electrodes 90 are arranged, and the two fixing ports 411 are provided on the upper end portion side.

  The plate-like member 400 and the COF substrate 410A provided on one side surface of the plate-like member 400 are bonded via an adhesive 420 provided in the fixed port 411. In the present embodiment, the adhesive 420 is provided in the fixing port 411 so as to cover the opening of the fixing port 411, and between the COF substrate 410 </ b> A and the plate-like member 400 at the periphery of the fixing port 411. It is filled in between. Note that the COF substrate 410A and the plate-like member 400 are not bonded except for the adhesive 420 provided in the fixing port 411. In this embodiment, the COF substrate 410B provided on the other side surface of the plate-like member 400 has the entire back surface bonded to the plate-like member 400 with the adhesive 420.

  As the adhesive 420 for bonding the COF substrate 410A and the plate member 400, it is preferable to use an adhesive having a relatively short curing time, such as an ultraviolet curable adhesive or an instantaneous adhesive.

  Here, a manufacturing method of the ink jet recording head of the present embodiment, in particular, a bonding method between the plate-like member 400 and the COF substrate 410 will be described. 5 to 6 are perspective sectional views showing a method for manufacturing the ink jet recording head.

  First, as shown in FIG. 5A, the COF substrate 410 </ b> B is bonded to one side of the side surface of the plate-like member 400. The bonding method between the plate member 400 and the COF substrate 410B is not particularly limited, and in this embodiment, the entire back surface of the COF substrate 410B is bonded to the plate member 400 with the adhesive 420.

  Next, as shown in FIG. 5B, the plate member 400 is tilted so that the other side of the side surface of the plate member 400 opposite to the surface to which the COF substrate 410B is bonded is the upper side in the vertical direction. The COF substrate 410A is placed on the side surface of the plate-like member 400 on the upper side in the vertical direction. At this time, the COF substrate 410A placed on the plate member 400 is held on the plate member 400 by its own weight. Further, since the COF substrate 410B provided on the other surface of the plate-like member 400 is bonded to the plate-like member 400, it does not fall. The COF substrate 410A is a substrate whose lower end connected to the lead electrode 90 is bent in advance. This is because if the lower end portion of the COF substrate 410A is bent along the plate member 400 after the COF substrate 410A is bonded to the plate member 400, the positioning of the COF substrates 410A and 410B is difficult, and the COF substrate is bent due to the bending. This is because the position of 410A is likely to be shifted.

  Then, the COF substrate 410A is positioned. Specifically, with respect to the COF substrate 410B previously bonded to the plate-like member 400, the COF substrate 410A is moved in the direction in which the lead electrodes 90 are arranged side by side, and the relative relationship between the COF substrates 410A and 410B is reached. Perform positioning. Thus, the wiring connected to the lead electrode 90 of the one COF substrate 410B bonded first and the wiring connected to the lead electrode 90 of the other COF substrate 410A are positioned in the juxtaposed direction. Can do.

  Next, as shown in FIG. 6, with the COF substrate 410A positioned, the adhesive 420 is applied to the fixing port 411 of the COF substrate 410A from the surface side, so that the inside of the fixing port 411 and the fixing port 411 The adhesive 420 is filled between the COF substrate 410A and the plate member 400 at the peripheral edge, and the adhesive 420 is cured to bond the COF substrate 410A and the plate member 400 together.

  In this way, by bonding the COF substrate 410A and the plate-like member 400 via the fixing port 411, the two COF substrates 410A and 410B can be bonded with high accuracy. . Thereby, when the wirings at the lower ends of the two COF substrates 410A and 410B are connected to the lead electrode 90, connection failure due to misalignment between the COF substrates 410A and 410B and the lead electrode 90 can be prevented. Incidentally, even when the adhesive 420 is applied to the entire back surface of the COF substrate 410A and the COF substrate 410A is in contact with the plate-like member 400, the positioning of the COF substrate 410A is performed. It is difficult to move the COF substrate 410A due to viscosity, and high-precision positioning cannot be performed. Further, if the entire back surface of the COF substrate 410A is bonded to the plate-like member 400 with the adhesive 420, the time for curing the adhesive 420 becomes long and the manufacturing efficiency decreases. In this embodiment, since the COF substrate 410A is positioned and the COF substrate 410A and the plate member 400 are partially bonded via the adhesive 420 in the region where the fixing port 411 is provided, the COF substrate 410A Can be easily bonded without causing a positional shift in a state of positioning with high accuracy. Further, since the COF substrate 410A is bonded to the plate-like member 400 only by the fixing port 411, the bonding area is narrow and the time for curing the adhesive 420 can be shortened. Thereby, it is possible to prevent the position of the COF substrate 410A from being shifted during the curing of the adhesive 420, to prevent the positioning accuracy from being lowered, and to improve the manufacturing efficiency. Further, by using an adhesive having a relatively short curing time, such as an ultraviolet curable adhesive or an instantaneous adhesive, as the adhesive 420, the curing time can be further shortened and positioning accuracy can be improved. it can.

  In addition, by providing the fixing port 411 on the lower end side connected to the lead electrode 90 side of the COF substrate 410A, the lower end portion of the COF substrate 410A that requires particularly high positioning accuracy can be positioned with high accuracy. That is, the three fixing ports 411 provided on the lower end portion side of the COF substrate 410A are for preventing the displacement of the region connected to the lead electrode 90 of the COF substrate 410A, and are connected to the lead electrode 90. It is preferable to provide a plurality of electrodes at a predetermined interval along the direction in which the lead electrodes 90 are arranged side by side. Further, the two fixing ports 411 provided on the upper end portion side of the COF substrate 410A are for preventing the upper end portion side of the COF substrate 410A from being peeled off from the plate member 400. The position and number are not particularly limited.

  In the above-described example, the entire back surface of the COF substrate 410B is bonded to the plate-like member 400. However, the present invention is not limited to this. For example, the fixing port 411 is also provided in the COF substrate 410B to be bonded first. The COF substrate 410B and the plate member 400 may be bonded via the fixing port 411. That is, the COF substrate 410A provided with the fixing ports 411 on both side surfaces of the plate-like member 400 may be bonded. In such a case, the curing time of the adhesive 420 can be shortened to improve manufacturing efficiency, and the first COF substrate 410B can be attached to the plate member 400 with high accuracy.

  In addition, as shown in FIG. 3, the buffer member which can be suitably formed with Teflon (registered trademark) etc. between the lower end surface of the plate-like member 400 and the lower end portion of the COF substrate 410 (COF substrates 410A and 410B). 430 is disposed. The lower end portion of the COF substrate 410 and the lead electrode 90 are electrically connected with conductive particles. That is, the COF substrate 410 is pressed to the lead electrode 90 side through the lower end surface by reducing the plate-like member 400. As a result, the conductive particles are crushed and a predetermined electrical connection is made between the COF substrate 410 and the lead electrode 90. At this time, the buffer member 430 functions to make the pressing force against the COF substrate 410 uniform. Here, the lower end surface of the plate-like member 400 and the lower end portion of the COF substrate 410 or the lower end surface of the plate-like member 400 in contact with the buffer member 430 have a surface accuracy within 5 times the particle diameter of the conductive particles. Is preferred. This makes it possible to equalize the pressing force applied to the conductive particles via the lower end portion of the COF substrate 410 in combination with the presence of the buffer member 430, and to reliably crush the conductive particles and to improve the electric power. This is because a secure connection is secured.

  In addition, the plate-like member 400 has a thermal conductivity that can dissipate heat so that the temperature of the drive circuit 200 is less than its junction temperature even when the ink jet recording head is used at its maximum guaranteed use temperature. Is desirable. As a result, even if the drive circuit 200 is operated under the harshest load conditions, it is possible to contribute to long-term stable driving of the drive circuit 200 by exhibiting a sufficient heat dissipation effect. For this reason, the plate-like member 400 in this embodiment is formed using SUS as a material. In this case, the heat generated by the drive circuit 200 can be absorbed by the ink flowing through the plate-shaped member 400 via the flow path forming substrate 10, and as a result, the heat generated by the drive circuit 200 can be effectively dissipated. Can be made. Similar actions and effects can be obtained by sufficiently reducing the distance between the surface of the flow path forming substrate 10 and the drive circuit 200 even when a metal such as SUS is not used. That is, the distance between the drive circuit 200 and the surface of the flow path forming substrate 10 is radiated so that the temperature of the drive circuit 200 is lower than the junction temperature even when the ink jet recording head I is used at its maximum guaranteed use temperature. What is necessary is just the distance to get.

  Note that the plate-like member 400 is preferably formed of a material having a linear expansion coefficient equivalent to that of the head case 110 which is a holding member described later in detail, and examples thereof include stainless steel and silicon.

  Further, as shown in FIG. 3, a compliance substrate 40 including a sealing film 41 and a fixing plate 42 is bonded onto the protective substrate 30. Here, the sealing film 41 is made of a material having low rigidity and flexibility (for example, a polyphenylene sulfide (PPS) film), and one surface of the reservoir portion 31 is sealed by the sealing film 41. The fixing plate 42 is made of a hard material such as metal (for example, stainless steel (SUS)). Since the region of the fixing plate 42 facing the reservoir 100 is an opening 43 that is completely removed in the thickness direction, one surface of the reservoir 100 is sealed only with a flexible sealing film 41. Has been.

  Further, a head case 110 that is a holding member is provided on the compliance substrate 40. The head case 110 is provided with an ink introduction path 111 that communicates with the ink introduction port 44 and supplies ink from ink storage means such as a cartridge to the reservoir 100. Further, the head case 110 is formed with a recess 112 in a region facing the opening 43 so that the deflection of the opening 43 is appropriately performed. Further, the head case 110 is provided with a wiring member holding hole 113 communicating with the through hole 33 provided in the protective substrate 30, and the wiring member is inserted into the wiring member holding hole 113 and connected to the lead electrode 90. It is connected. The wiring member inserted through the wiring member holding hole 113 of the head case 110 is bonded to the head case 110 via an adhesive 120.

  In addition, as a material of such a head case 110, metal materials, such as stainless steel, are mentioned, for example.

  Here, as shown in FIG. 4, the COF substrate 410 is provided with a holding port 412 penetrating in the thickness direction in a region facing the inner surface of the wiring member holding hole 113 of the head case 110. The plate member 400 is bonded to the head case 110 via an adhesive 120 via a holding port 412 provided on the COF substrate 410. That is, the plate member 400 of the wiring member and the head case 110 are directly bonded via the adhesive 120 provided in the holding port 412. In the present embodiment, one holding port 412 is provided in the central portion of the wiring member holding hole 113 in the juxtaposition direction of the lead electrodes 90 on the lower end side of the COF substrate 410. Further, in the present embodiment, the fixing port 411 is provided at the same height as the holding port 412, and the fixing ports 411 on both ends of the lead electrode 90 in the juxtaposition direction function as the holding port 412. That is, by bonding the adhesive 420 that bonds the plate-like member 400 and the COF substrate 410 and the head case 110 via the adhesive 120, the plate-like member 400 and the head case are also formed in the fixed port 411 region. 110 is directly bonded via two adhesives 420 and 120.

  Further, since the adhesive 120 that bonds the plate member 400 and the head case 110 is filled between the plate member 400 and the COF substrate 410 at the peripheral portion of the holding port 412, the plate member 400 and the COF. It also functions as an adhesive that bonds the substrate 410. That is, the holding port 412 is not used when the above-described COF substrate 410A is bonded to the plate-shaped member 400, but when the head case 110 and the plate-shaped member 400 are bonded, the plate-shaped member 400 and the COF substrate 410A. It also functions as a fixing port 411 for bonding the two.

  Thus, by directly bonding the plate-like member 400 and the head case 110 without using the COF substrate 410, the plate-like member 400 can be securely held by the head case 110. That is, by adhering the rigid bodies of the head case 110 and the plate-like member 400, the state where the COF substrate 410 and the lead electrode 90 are securely connected can be maintained. It is possible to prevent problems such as disconnection and disconnection. In addition, the head case 110 and the plate-like member 400 are formed of a material having the same linear expansion coefficient, in this embodiment, stainless steel, so that when the ink jet recording head I is expanded or contracted by heat, the head case Warpage and breakage due to the difference in linear expansion coefficient between 110 and the plate-like member 400 can be prevented. By the way, if the head case 110 and the plate-like member 400 are made of materials having different linear expansion coefficients, the plate-like member 400 may press the flow path forming substrate 10 and the flow path forming substrate 10 may be cracked. There is.

  In the present embodiment, the head case 110 and the plate-like member 400 are bonded via the adhesive 120 in the region where the holding port 412 of the COF substrate 410 is provided (including the region where the fixing port 411 is provided). However, the COF substrate 410 and the head case 110 may be bonded together, and the space between the wiring member and the through hole 33 and the wiring member holding hole 113 of the protective substrate 30 is made of a molding material. You may make it mold.

  In the ink jet recording head described above, ink is taken in from an ink introduction port connected to an external ink storage unit (not shown), and the interior from the reservoir 100 to the nozzle opening 21 is filled with ink. In accordance with the recording signal, a voltage is applied between the lower electrode film 60 and the upper electrode film 80 corresponding to the pressure generation chamber 12, and the elastic film 50, the insulator film 55, the lower electrode film 60 and the piezoelectric layer 70 are moved. By deflecting and deforming, the pressure in each pressure generating chamber 12 is increased and ink droplets are ejected from the nozzle openings 21.

  Furthermore, according to the present embodiment, since the drive circuit 200 and the lead electrode 90 of the piezoelectric element 300 are connected via the COF substrate 410 on which the drive circuit 200 is mounted, manufacturing is easier than with the wire bonding method. Become. Further, since the COF substrate 410 is connected to the lead electrode 90 at the lower end and is raised almost vertically, it can be reduced in size without increasing in size. In addition, since the COF substrate 410 is directly connected to the lead electrode 90, even if the piezoelectric elements 300 are arranged at a high density, the connection between the lead electrode 90 and the COF substrate 410 does not occur, and the density can be increased. Can be easily achieved. Furthermore, since the drive circuit 200 is bonded to the side surface of the plate-like member 400 via the COF substrate 410, the heat generated by the drive circuit 200 can be radiated well.

(Other embodiments)
As mentioned above, although one Embodiment of this invention was described, the basic structure of this invention is not limited to what was mentioned above. For example, in Embodiment 1 described above, the COF substrates 410 (410A, 410B) are provided on both side surfaces of the plate-like member 400, but two or more COF substrates 410 may be provided on each side surface. .

  In Embodiment 1 described above, one COF substrate 410 (410A, 410B) is provided on each of both side surfaces of the plate-like member 400. However, the present invention is not limited to this. The printed circuit board 410 may be provided only on one side surface, or a continuous printed circuit board may be used as the printed circuit board 410 on both side surfaces. However, as in the first embodiment described above, when two COF substrates 410 (410A, 410B) are provided, one on each side surface of the plate-like member 400, positioning becomes difficult. By fixing with the adhesive using the fixing port 411 of the printed circuit board 410A, the effect that positioning can be performed easily and with high accuracy can be obtained more reliably.

  In the first embodiment described above, each fixing port 411 is an independent opening. However, the present invention is not limited to this. For example, the fixing port 411 is cut on both side surfaces of the COF substrate 410 in the parallel arrangement direction of the lead electrodes 90. You may make it provide as a notch part.

  Further, in the first embodiment described above, the plate member 400 and the head case 110 are directly bonded via the fixing ports 411 on both ends of the COF substrate 410 in the direction in which the lead electrodes 90 are arranged in parallel. However, the holding port 412 different from the fixing port 411 may be further provided on both ends of the COF substrate 410. Further, as the holding port, for example, it may be provided as a notch on both side surfaces of the COF substrate 410 in the direction in which the lead electrodes 90 are arranged. Of course, you may make it adhere | attach the COF board | substrate 410 with the plate-shaped member 400 in the outer peripheral part.

  Furthermore, in the first embodiment described above, two rows in which the pressure generation chambers 12 are arranged in parallel on the flow path forming substrate 10 are provided, but the number of rows in this case is not particularly limited. There may be one row or three or more rows. In the case of a plurality of rows, at least two rows may be provided so as to face each other.

  In the first embodiment described above, the plate-like member 400 and the COF substrates 410A and 410B are bonded via the adhesive 420, but the present invention is not particularly limited thereto. For example, either one or both of the COF substrate 410A and the COF substrate 410B may be joined to the plate member 400 by a double-sided tape. Here, when the COF substrates 410A and 410B are affixed to the plate-like member 400 with a double-sided tape, the bending angle of the end portions connected to the lead electrodes 90 of the COF substrates 410A and 410B may be made larger than 90 degrees. . As a result, even if the double-sided tape is affixed to both sides of the plate-like member 400 in advance, the COF substrates 410A and 410B may be joined to the plate-like member 400 by the double-sided tape before the alignment of the COF substrates 410A and 410B. Absent. Therefore, even when the plate-like member 400 and the COF substrates 410A and 410B are bonded with a double-sided tape, the alignment between the COF substrate 410A and the COF substrate 410B can be performed. After the alignment between the COF substrate 410A and the COF substrate 410B, the COF substrates 410A and 410B are pressed against the plate-like member 400 side, so that the positional deviation between the COF substrate 410A and the COF substrate 410B does not occur. The COF substrates 410A and 410B and the plate-like member 400 can be joined with a double-sided tape.

  Moreover, when the plate-like member 400 of the first embodiment described above is formed of a conductive material, the plate-like member 400 may be grounded. By grounding the plate-like member 400 in this way, noise generated from the drive circuit 200 or the like can be shielded, and inhibition of the drive signal or the like due to noise can be suppressed. Further, by grounding the plate-like member 400, it is possible to reduce the generation of noise due to floating metal when the ink jet recording head I is moved.

  Furthermore, when the plate-like member 400 and the head case 110 are formed of a conductive material, both can be obtained by using a conductive adhesive as the adhesive 120 that bonds the head case 110 and the plate-like member 400. Can be conducted. Then, by conducting the plate-like member 400 and the head case 110, if one of them is grounded, both can be grounded, and the wiring for grounding and the process of grounding can be reduced. Further, by grounding the plate-like member 400 and the head case 110, noise generated by the drive circuit 200 and the like can be shielded. In addition, by grounding the plate-like member 400 and the head case 110, it is possible to reduce the generation of noise due to floating metal. Note that the floating metal here refers to a member that is not grounded among conductive members constituting the ink jet recording head I. Further, the grounding of the head case 110 and the plate-like member 400 may be performed via the ground wiring of the COF substrates 410A and 410B, for example.

  In the first embodiment described above, the actuator device having the thin film type piezoelectric element 300 is described as the pressure generating element for causing the pressure change in the pressure generating chamber 12, but the present invention is not particularly limited thereto. It is possible to use a thick film type actuator device formed by a method such as attaching a green sheet or a longitudinal vibration type actuator device in which piezoelectric materials and electrode forming materials are alternately stacked to expand and contract in the axial direction. it can. In addition, as a pressure generating element, a heat generating element is disposed in the pressure generating chamber, and a liquid droplet is discharged from the nozzle opening by a bubble generated by heat generation of the heat generating element, or static electricity is generated between the diaphragm and the electrode. Thus, a so-called electrostatic actuator that discharges liquid droplets from the nozzle openings by deforming the diaphragm by electrostatic force can be used.

  The ink jet recording head according to the above-described embodiment constitutes a part of a recording head unit including an ink flow path communicating with an ink cartridge or the like, and is mounted on the ink jet recording apparatus. FIG. 7 is a schematic view showing an example of the ink jet recording apparatus. As shown in the drawing, the recording head units 1A and 1B having the ink jet recording head I according to the above-described embodiment are provided with cartridges 2A and 2B constituting the ink supply means in a detachable manner, and the recording head units 1A and 1B. Is mounted on a carriage shaft 5 attached to the apparatus main body 4 so as to be movable in the axial direction. The recording head units 1A and 1B, for example, are configured to eject a black ink composition and a color ink composition, respectively.

  The driving force of the driving motor 6 is transmitted to the carriage 3 via a plurality of gears and timing belt 7 (not shown), so that the carriage 3 on which the recording head units 1A and 1B are mounted is moved along the carriage shaft 5. The On the other hand, the apparatus body 4 is provided with a platen 8 along the carriage shaft 5, and a recording sheet S that is a recording medium such as paper fed by a paper feed roller (not shown) is wound around the platen 8. It is designed to be transported.

  In the above embodiment, an ink jet recording head has been described as an example of a liquid ejecting head, and an ink jet recording apparatus has been described as an example of a liquid ejecting apparatus. The present invention is intended for the entire apparatus, and can of course be applied to a liquid ejecting head and a liquid ejecting apparatus that eject liquid other than ink. Other liquid ejecting heads include, for example, various recording heads used in image recording apparatuses such as printers, color material ejecting heads used in the manufacture of color filters such as liquid crystal displays, organic EL displays, and FEDs (field emission displays). Examples thereof include an electrode material ejection head used for electrode formation, a bio-organic matter ejection head used for biochip production, and the like, and can also be applied to a liquid ejection apparatus provided with such a liquid ejection head.

  In these liquid ejecting apparatuses, the grounding unit connected to the ground wire or the like and grounded may be connected to the head case 110 and the plate-like member 400 of the liquid ejecting head to be grounded.

FIG. 2 is an exploded perspective view of a recording head according to Embodiment 1 of the invention. FIG. 3 is a plan view of the recording head according to the first embodiment of the invention. FIG. 3 is a cross-sectional view of the recording head according to the first embodiment of the invention. 2A and 2B are a side view and a sectional view of the recording head according to the first embodiment of the invention. FIG. 4 is a perspective cross-sectional view illustrating the method for manufacturing the recording head according to the first embodiment of the invention. FIG. 4 is a perspective cross-sectional view illustrating the method for manufacturing the recording head according to the first embodiment of the invention. 1 is a schematic view showing an ink jet recording apparatus according to an embodiment of the present invention.

Explanation of symbols

  I ink jet recording head (liquid ejecting head), 10 flow path forming substrate, 12 pressure generating chamber, 13 communication section, 14 ink supply path, 15 communication path, 21 nozzle opening, 30 protective substrate, 32 piezoelectric element holding section, 33 Through hole, 60 Lower electrode film, 70 Piezoelectric layer, 80 Upper electrode film, 90 Lead electrode, 100 Reservoir, 110 Head case (holding member), 113 Wiring member holding hole, 120 Adhesive, 200 Drive circuit, 300 Piezoelectric element (Pressure generating element), 400 plate-like member (supporting member), 410, 410A, 410B COF substrate (wiring substrate), 420 adhesive, 430 buffer member

Claims (9)

A flow path forming substrate in which a pressure generating chamber communicating with a nozzle opening for ejecting liquid is formed;
A pressure generating element formed to apply a pressure for injecting liquid into the pressure generating chamber;
A lead electrode connected to the pressure generating element;
A flexible wiring board connected to the lead electrode and a support member bonded to the wiring board;
The wiring board is provided with a fixing port penetrating in the thickness direction, and the wiring board and the support member are bonded to each other through an adhesive provided in the fixing port. Jet head.   The liquid ejecting head according to claim 1, wherein a plurality of the fixing ports are provided in a region facing the support member at a predetermined interval in a direction in which the lead electrodes are arranged side by side. A row in which the pressure generating elements are arranged side by side is arranged,
The support member is disposed in the parallel direction,
The wiring board is bonded on both sides of the support member,
The liquid ejecting head according to claim 1, wherein the fixing port of the wiring board is provided at a position facing both side surfaces of the supporting member.   The liquid ejecting head according to claim 1, wherein the adhesive is made of an ultraviolet curable adhesive.   The liquid ejecting head according to claim 1, wherein the wiring substrate and the lead electrode are electrically connected with conductive particles.   The liquid ejecting head according to claim 1, wherein a buffer member is provided on a lower end surface of the support member.   A liquid ejecting apparatus comprising the liquid ejecting head according to claim 1.   The liquid ejecting apparatus according to claim 7, further comprising a grounding unit that grounds the support member. A flow path forming substrate in which a pressure generation chamber communicating with a nozzle opening for injecting liquid is formed; a pressure generation element formed to apply pressure for injecting liquid into the pressure generation chamber; and the pressure generation A lead electrode connected to the element; a flexible wiring board connected to the lead electrode; and a support member bonded to the wiring board, and at least on a side surface on the lower end side of the wiring board. Is a method of manufacturing a liquid jet head provided with a fixing port penetrating in the thickness direction,
Bonding the wiring board to one of the support members;
Placing the wiring board on the other of the support members and positioning the other wiring board with respect to one of the wiring boards;
And a step of bonding the wiring board and the support member with an adhesive of the fixing port provided on the wiring board disposed on the other side of the support member. Method.

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