JP2002086739A - Method of manufacturing inkjet head, inkjet head, and inkjet recording apparatus - Google Patents

Abstract

An object of the present invention is to reduce protrusion when a printed circuit board is connected with solder or an anisotropic conductive film, and to improve reliability of electrode connection and head assemblability. I do. According to the method of manufacturing an ink jet head of the present invention, an electric connection member is interposed between a printed board and an electrode board, and the temperature at the end of the printed board at the press contact surface is low from above the printed board. The crimping head having a gradient is pressed to make the amount of protrusion of the electric connection member on the end side of the printed board smaller than the amount of protrusion of the electric connection member on the end side of the electrode board. Therefore, the liquid chamber substrate of the head can be easily joined, and the connection reliability is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing an ink jet head, an ink jet head and an ink jet recording apparatus, and more particularly to an ink jet recording apparatus using an electrostatic ink jet head.

[0002]

2. Description of the Related Art The non-impact recording method has attracted attention for office use and the like because noise generation during recording is small enough to be ignored. Among them, the so-called inkjet recording method, which is capable of high-speed recording and can perform recording on plain paper without requiring a special fixing process, is an extremely powerful method, and various methods have been conventionally proposed or already commercialized. Has been in practical use. In such an ink jet recording method, recording is performed by flying small droplets of a recording liquid, so-called ink, and attaching the recording liquid to a recording medium. Depending on the control method for controlling the direction, it is roughly classified into several types. Above all, in recent years, there is a technique described in Japanese Patent Application Laid-Open No. 4-52214 as a method capable of achieving high density and high integration using a silicon substrate, and a method described in Japanese Patent Application Laid-Open No. 3-293141 as a method of manufacturing the same. This is a recording method in which a voltage is applied between a substrate and an electrode of a vibration plate and ink is ejected by bending the vibration plate by electrostatic force. As a head forming method, a liquid chamber and a vibration plate are etched on a silicon substrate. Is formed. Also, as a configuration of this inkjet head,
As described in JP-A-6-50601,
By providing a diaphragm in a part of the ink liquid chamber and providing the counter electrode in a direction different from that of the ink liquid chamber, the head is made denser and thinner, and stable driving of the diaphragm is realized. That is, a common electrode is formed on a diaphragm, an individual electrode facing the common electrode is formed on an electrode substrate, and both electrodes are precisely arranged with a minute gap. In addition, by using a substrate such as silicon, which is easily etched, as an electrode substrate, a groove for forming a minute gap and an individual electrode located at the bottom thereof can be easily formed.

Japanese Patent Application Laid-Open Nos. Hei 9-300269 and Hei 7-246706 disclose F-type electrostatic recording devices.
The PC connection method is shown. By the way, when a side shooter type head is produced by an electrostatic ink jet recording apparatus, in order to reduce the head width, as shown in FIG. May be created. This is because of the size of the diaphragm substrate 122 in which at least the portion of the diaphragm is formed, and the size of the liquid chamber substrate 121 in which it is necessary to form a liquid chamber and a fluid resistance, a flow path, a common liquid chamber, and the like corresponding thereto. This is because the difference can be effectively used and the head size can be reduced. Further, with such a configuration, there is no need to newly form a connection region of the FPC 124 other than the region where the liquid chamber substrate 121 is formed, and there is a great merit that the size of the head can be reduced.

[0004]

However, in the case of an electrostatic head, there is only a very small gap (about several μm) between the electrode substrate and the diaphragm facing the electrode substrate. This is because the drive voltage depends on the gap length, and it is necessary to form a minute gap for driving at a low voltage. Therefore, the diaphragm substrate on which the diaphragm is formed is also thin, and when joined to the electrode substrate, the height of the diaphragm substrate becomes extremely low. As an effective means for connecting a printed circuit board such as an FPC to such an ink jet head, there is a method using solder or an anisotropic conductive film, but when thermocompression bonding is performed by these methods, solder, Protrusion of the anisotropic conductive film occurs. In particular, in the common electrode portion having a large electrode width, extremely large protrusion occurs. If this protrusion is large, the head having the configuration as shown in FIG. 11 interferes with the liquid chamber substrate 121.
This will hinder the joining of the liquid chamber substrate 121. Further, even when the liquid chamber substrate 121 does not overhang on the connection portion of the printed circuit board 124 as shown in FIG. 11, the protruding portion is rubbed by the nozzle wiping, and the wiper may be damaged or the connection state of the printed circuit board 124 may be damaged. Adversely affect
The reliability of the head decreases.

SUMMARY OF THE INVENTION The present invention has been made in view of these problems, and reduces the protrusion when a printed circuit board is connected with solder or an anisotropic conductive film, thereby improving the reliability of electrode connection and the assemblability of a head. It is an object to provide an ink-jet head and an ink-jet recording apparatus which perform the following.

[0006]

In order to solve the above problems, a nozzle substrate having a nozzle for discharging ink, a liquid chamber communicating with the nozzle, and a method for applying pressure to the ink in the liquid chamber are provided. A diaphragm substrate on which a diaphragm of
An ink jet that has an electrode substrate on which individual electrodes are formed by being opposed to the diaphragm with a small gap therebetween, and a printed substrate for applying a voltage to the individual electrodes, and the printed substrate and the electrode substrate are connected by an electrical connection member According to the method of manufacturing a head, a pressure bonding head having a low temperature gradient at the end of the printed circuit board at the press-contact surface is pressed from above the printed circuit board with an electrical connection member interposed between the printed circuit board and the electrode board. The feature is that the amount of protrusion of the electrical connection member at the end of the printed circuit board is made smaller than the amount of protrusion of the electrical connection member at the end of the electrode board.
In addition, an electric connection member is interposed between the printed board and the electrode board, and the pressure bonding head is tilted so that the height from the printed board end to the electrode board is smaller than the height from the electrode board end to the printed board. Press on the printed circuit board.
Therefore, when the printed circuit board is crimped and connected to the electrode substrate with an electric connection member such as a solder or an anisotropic conductive film, the amount of protrusion of the electric connection member on the end side of the printed circuit board is protruded from the end of the electrode substrate. The liquid chamber substrate of the head having a configuration in which the nozzle plate overhangs on the connection portion of the printed circuit board can be easily joined. Also, the liquid chamber substrate is on the connection part of the printed circuit board,
In a head with a configuration that does not overhang, there is no rubbing of the board connection part due to wiping etc.,
Connection reliability is improved.

Another feature of the present invention is an ink jet head manufactured by the above method of manufacturing an ink jet head.

Further, in the ink jet head according to another aspect of the present invention, the amount of protrusion of the electrical connection member at the end of the printed board is smaller than the amount of protrusion of the electrical connection member at the end of the electrode board. Therefore, the liquid chamber substrate of the head can be easily joined.

An ink jet head according to still another aspect of the present invention, when a printed board and an electrode board are connected,
The height from the end of the printed circuit board to the electrode substrate is lower than the height from the end of the electrode substrate to the printed circuit board. Therefore, connection reliability is improved.

Another feature of the present invention is that the common electrode formed on the printed circuit board in the ink jet head forms a comb-shaped electrode. Therefore, the electric connection member enters between the combs, and the amount of protrusion to the common electrode side can be reduced.

Another feature of the invention is that a step is provided between an end of a common electrode formed on a printed circuit board of an ink jet head and an end of an individual electrode adjacent to the common electrode. Therefore, a large protrusion that adversely affects the assembling process due to an increase in the escape area of the electric connection member can be prevented.

Further, an ink jet recording apparatus according to the present invention includes the above ink jet head.

[0013]

According to the method of manufacturing an ink jet head of the present invention, an electric connection member is interposed between a printed circuit board and an electrode board, and the temperature of the press-contact surface at the end of the printed circuit board from the printed circuit board. Presses the pressure bonding head having a low temperature gradient so that the amount of protrusion of the electrical connection member at the end of the printed circuit board is smaller than the amount of protrusion of the electrical connection member at the end of the electrode substrate. Therefore, the liquid chamber substrate of the head can be easily joined, and the connection reliability is improved.

[0014]

FIG. 1 is a schematic sectional view showing the structure of an ink jet recording apparatus according to the present invention. As shown in FIG. 1, the ink jet recording apparatus 101 includes four ink cartridges 102 each containing ink of each color of cyan C, magenta M, yellow Y, and black BK, and a plurality of nozzles. Ink supply 4
Inkjet heads 103, a carriage 104 on which the ink cartridges 102 and the inkjet heads 103 are mounted, and a paper feed tray 105 for storing recording paper.
a transport roller 108 for transporting the recording paper from the a, 105b or the manual feed table 106 to the printing unit 107; and a discharge roller 110 for discharging the printed recording paper to a discharge tray 109. When printing the image data sent from the host device on the recording paper, the carriage 104 scans the carriage roller 111 while scanning the carriage roller 1.
In 08, ink is ejected from the nozzles of the inkjet head 103 onto the recording paper sent to the printing unit 107 in accordance with image data to record characters and images.

Next, the ink jet recording apparatus 10 shown in FIG.
2 is an external view of an ink jet head according to a first embodiment of another invention, FIG. 3 is a view taken in the direction of arrow A in FIG. 2, and FIG.
As shown in FIG. 4 which is a cross-sectional view taken along the line B ′, the liquid chamber substrate 11,
A diaphragm board 12, an electrode board 13, a flexible printed wiring board (hereinafter abbreviated as FPC) 14, which is a printed board,
Two rows of staggered nozzles 15, F arranged in a row
The base 16 of the PC 14, the electrode lead 17 of the FPC 14,
The resist layer 18 of the FPC 14, the individual electrode 19, the vibration plate 20 also serving as a common electrode, the liquid chamber 21, and the electrode lead 17 of the FPC 14 and the individual electrode 19 of the electrode substrate 13 are electrically connected, for example, solder, anisotropic conductive material. It comprises a conductive adhesive 22 such as a film or an anisotropic conductive paste. The common liquid chamber 23 is a liquid chamber that communicates with each liquid chamber 21 and supplies ink. The gap 24 is a gap between the individual electrode 19 and the diaphragm 20. The fluid resistance 25 is formed between the liquid chamber 21 and the common liquid chamber 23 and when the liquid chamber substrate 11 and the diaphragm substrate 12 are close to each other. The electrode substrate 13 is made of a conductor or a semiconductor, and includes a conductive substrate 26 and an insulating layer 27 formed thereon. The ink supply port 28 is a supply port for supplying ink from an ink tank (not shown) to the communicating common liquid chamber 23. Further, the liquid chamber 21 and the nozzles 15 are provided in two rows in a staggered arrangement, and the nozzle pitch is set to two.
By doubling the size, the ink can be formed as a common ink supply port 28 for supplying ink to both, so that the head area can be used effectively. Note that, for the sake of simplicity, ink supply means to the ink supply port and the like are omitted.

The liquid chamber substrate 11 is formed with a groove by a known method such as machining such as dicing or electroforming such as etching, and is joined to the diaphragm substrate 12 so that the nozzle 15 and the liquid chamber 21 are shared. A liquid chamber 23 can be formed. As a material of the liquid chamber substrate 11,
Metals such as stainless steel, semiconductors such as Si, and insulating materials such as glass are used. In addition, as a joining method, a dry film may be used. A nozzle substrate (not shown) is bonded on the liquid chamber substrate 11 with an adhesive. The ejection surface of the nozzle surface is subjected to a water-repellent treatment by a known method (eg, plating or coating with a water-repellent agent) in order to ensure water repellency with the ink.

Further, the diaphragm substrate 12 is formed by etching a metal such as stainless steel or a semiconductor such as Si.
This is preferable because a fine pattern can be formed with a desired thickness with high accuracy and the diaphragm substrate itself can be used as a common electrode. When an insulating material such as glass is used, a common electrode can be formed by depositing a metal such as Al, Cu, Cr, Ni, or Au on the surface by vapor deposition or sputtering. The diaphragm substrate 12 has a concave portion in which the diaphragm 20 is formed on the bottom surface by a known method such as mechanical processing such as partial polishing or electroforming such as etching. Further, a part of the diaphragm substrate 12 is
The common electrode pad extends to the individual electrode 19 side and is connected to a printed circuit board.

The electrode substrate 13 is formed by etching a metal such as stainless steel or a semiconductor such as Si.
Forming a gap 24 of a desired height, further to the gap 24, an insulating material such as resin or SiO ₂ insulating layer 2
7 is formed. On top of that, Ni, A
1, electrode material such as Ti / Pt, Cu, etc.
An individual electrode can be formed only in the gap by forming a film to a desired thickness by a film forming technique such as VD or vapor deposition, and then forming and etching a photoresist. Therefore, the structure of the electrode substrate 13 is made of a conductor or a semiconductor and has a conductive substrate 26.
Then, a concave portion corresponding to the gap 24 with the diaphragm 20 is formed on the insulating layer 27 formed thereon, and the individual electrode 19 formed of a conductive material is formed on the bottom surface thereof. ing. In addition, on the surface of the electrode substrate 13, by pulling out and fixing a part of the common electrode to a region other than the individual electrode forming portion, the individual electrode and the common electrode can be formed in substantially the same plane. This facilitates connection with a printed circuit board (printed circuit board for driving the head) described later. Note that the diaphragm substrate 12 and the electrode substrate 13 are made of an adhesive,
Bonded by anodic bonding, direct bonding, or the like. Further, on the individual electrode 19, an insulating layer made of SiO ₂ or a resist material may be formed except for a connection portion with a printed board for the purpose of further preventing the electrode from being damaged by short circuit or discharge. .

On the other hand, the printed circuit board 14 connected to the individual electrodes 19 includes a plate-shaped printed circuit board made of glass epoxy resin or phenol resin, a polyimide resin,
Film-shaped printed circuit board (FP) made of PET resin, etc.
C) is used. On the printed circuit board 14, electrode leads 17 for applying a voltage to the individual electrodes 19 are formed. As a method of electrically connecting the electrode leads 17 on the printed circuit board 14 to the individual electrodes 19 and the electrode pads of the common electrode, for example, a method of thermocompression bonding with solder, a method of thermocompression bonding with an anisotropic conductive adhesive, an electrode There are methods such as pressure bonding between wires, wire bonding method, etc., but wire bonding method requires the height of the wire, and furthermore, the wire part is made of resin etc. to prevent mechanical damage of the wire and connection between wires It is not preferable because there is a drawback that the sealing portion becomes high. The method of thermocompression bonding with solder, the method of thermocompression bonding with an anisotropic conductive adhesive, and the method of press-contacting between electrodes can connect multiple electrodes at once,
This is an excellent method in that processing is easy, low cost, and the height for connection is low. Further, among these methods, in the method of thermocompression bonding with solder or an anisotropic conductive film, the substrates are bonded to each other after the pressure bonding, so that the electrical connection and the mechanical connection between the electrode substrate and the printed board are simultaneously performed. Therefore, this is an excellent connection method in that it is not necessary to separately reinforce the connection portion so as not to be disconnected in a head assembling process or a printing operation. Such a connection method of thermocompression bonding with solder or an anisotropic conductive film is performed in steps as shown in FIG. Here, FP is used as the driving printed circuit board.
This is an example in which C is used, and an anisotropic conductive film is used to connect it to the electrode substrate. Anisotropic conductive film (anisotropic conductive film) 22
Is a material in which conductive particles called fillers are dispersed in a thermoplastic or thermosetting resin. Thus, the filler comes into contact with both electrodes, thereby establishing electrical continuity between the electrodes. As shown in FIG. 5A, first, the anisotropic conductive film 22 is positioned on the electrode portion of the printed circuit board 14 such as an FPC so as to be positioned on the end face of the FPC, and then temporarily press-bonded, and the FPC or the like is formed. The printed circuit board 14 and the anisotropic conductive film 22 are brought into close contact with each other. Thereafter, as shown in FIG. 5B, the protective film of the anisotropic conductive film 22 is removed, and the electrode pads of the electrode substrate and the electrode leads of the FPC are aligned, and as shown in FIG. As shown in ()), the heated pressure bonding head 51 is pressed against the electrode area to perform thermocompression bonding. After the driving printed circuit board 14 is connected to the electrode substrate of the head to which the diaphragm substrate 12 has been joined, the nozzle plate is joined to the diaphragm substrate with an adhesive to complete the head unit.

In order to improve the ejection efficiency of the ink jet head, it is preferable that the distance between the nozzle and the diaphragm is as small as possible. For that purpose, it is necessary to reduce the height of the liquid chamber 21, resulting in a very flat structure. When the printed circuit board 14 is connected with the solder or the anisotropic conductive film 22 as described above with the head having such a form, the protrusion of the solder and the anisotropic conductive film generated by the press-bonding becomes a problem. In particular, in the case of a head as shown in FIG. 3 having an effective configuration for realizing a compact head,
If the protrusion is large, it will hinder the joining of the nozzle plates. As described above, when the solder or the anisotropic conductive film 22 is used, as a method of reducing the protrusion as described above, for example, as shown in FIG. 6, bonding is performed using a pressure bonding head 51 having a thermal gradient, that is, The temperature of the solder (the circle X surrounded by the broken line in the figure) and the temperature of the solder and the anisotropic conductive film 22 inside (the circle Y surrounded by the broken line in the figure) are lowered. If this is the case, the amount of protrusion outside the inside can be made smaller than that outside, and adverse effects on the nozzle plate assembly process and the like can be avoided. As a method of forming the temperature gradient, for example, as shown in FIG. 6, a temperature adjusting member 52 such as a metal block having good heat dissipation is provided on the diaphragm substrate side, or irregularities are formed on the surface of the pressure bonding head 51 on the diaphragm substrate side. For example, there is a method of increasing the surface area. Also,
As another means for reducing the amount of protrusion, pressure bonding is performed by inclining the pressure bonding head 51 as shown in FIG. 7 or pressure bonding using a pressure bonding head in which the end of the pressure bonding head 51 is tilted as shown in FIG. From the edge of the electrode substrate to the diaphragm substrate 12
The printed circuit board 14 can be connected so as to be lower toward the diaphragm, and the protrusion of the solder or the anisotropic conductive film toward the diaphragm substrate can be reduced.

FIG. 9 is a plan view showing an electrode substrate and a diaphragm substrate of the head in this embodiment. FIG. 1 shows a configuration in which power is supplied to a diaphragm at a pad portion of an electrode substrate. In the electrostatic head, the configuration in which the diaphragm also serves as the common electrode is simple and preferable.
If the electric resistance of the second electrode is large, it is impossible to drive a large number of diaphragms with good characteristics. Therefore, usually, the common electrode pad 4
2 is formed several times wider than the individual electrode pads 41. When the printed circuit boards are joined by solder or an anisotropic conductive film, the protrusion at the large common electrode pad 42 is larger than the protrusion at the individual electrode pad 41. As a means for solving such a problem, for example, as shown in FIG. 10A, the common electrode portion on the printed circuit board side is divided into comb-shaped electrodes 43 so as to electrically connect to the gap between the electrodes. Since the member enters, the amount of protrusion can be reduced. Also, by doing so, the bonding area of the common electrode portion of the electrode substrate and the printed circuit board increases,
There is also an effect that joining strength increases. Another method for reducing the amount of protrusion of the common electrode portion is shown in FIG.
As shown in FIG.
And a step is provided between the electrode substrate and the electrode substrate. As a result, the escape area of the electric connection member is increased, so that a large protrusion that adversely affects the assembling process and the like can be suppressed.

As an experimental example, a diaphragm substrate having a thickness of 0.1 mm joined to an electrode substrate was used.
[μm] anisotropic conductive film and thickness of about 50 [μm] FP
C was implemented. First, a comparison was made between a pressure bonding head (pressure bonding head A) having a pressure bonding surface parallel to the electrode substrate as shown in FIG. 5 and a pressure bonding head (pressure bonding head B) inclined about 2 degrees as shown in FIG. Using these two types of pressure bonding heads, bonding was performed 50 times each, and the contact check between the electrode substrate and the FPC was performed. As a result, a total connection state of 100 pieces was good in both cases. Next, a nozzle plate was attached to these samples, a head as shown in FIG. 3 was assembled, and printing evaluation was performed.
All the samples of the crimping head B obtained good results, but six of the samples of the crimping head A were NG. When the head was disassembled and analyzed, it was found that there was an ink leak at the interface between the nozzle plate and the diaphragm substrate. At the same location, an ink mark was observed that appeared to protrude from the anisotropic conductive film, indicating that the anisotropic conductive film protruded greatly and resulted in poor joining of the nosle plate. Therefore, all of these samples were decomposed and FP
The flatness of C and the amount of protrusion of the anisotropic conductive film were measured. As a result, the respective average values were as shown in Table 1 below.

[0023]

[Table 1]

From Table 1, it was confirmed that the sample of the pressure bonding head A from which the defective head came out had an FPC flatness of 20 [μm] and was almost parallel to the electrode substrate.
As a result, the protruding amounts on the inner side (diaphragm substrate side) and the outer side (electrode substrate end face side) of the joint were almost equal. on the other hand,
In the pressure-bonding head B sample from which no defective head appeared, the parallelism was 50 [μm], the FPC became lower from the outside to the inside, and the inside and outside protrusion amounts were extremely different. In this way, by tilting the pressure bonding head and pressing, the protrusion of the anisotropic conductive film can be increased to the outside of the electrode substrate, and a high-quality head can be manufactured without hindering the next step of nozzle bonding. did it. Next, as shown in FIG. 6, the pressure bonding surfaces of the electrode substrate and the pressure bonding head are parallel to each other, but a heat sink as a temperature adjusting member 52 is fixed inside the pressure bonding head 51, and the temperature difference between the inside and the outside of the pressure bonding head 51 is reduced. Spreading and crimping were performed to produce 50 samples (crimping head C sample). As a result, good results were obtained for all the prints. Table 2 below shows the results of decomposing in the same manner as above and measuring the amount of protrusion and the like.

[0025]

[Table 2]

From Table 2, it was confirmed that the amount of protrusion outside could be reduced by the temperature gradient of the pressure bonding head. As shown in FIG. 10 (c), the samples prepared in these experiments tended to have a large protrusion at the common electrode portions provided at both ends of the FPC and a small protrusion at the central portion. F used in the above experiment
The common electrode of the PC was a straight pattern having a width of 600 [μm], but as shown in FIG.
As shown in FIG. 10B, an SPC-shaped pattern and an FPC in which only the common electrode portion is cut off by 150 [μm] as shown in FIG.
The compression bonding was performed, and the protruding height of the anisotropic conductive film at the common electrode portion of each FPC was compared. The results are shown in Table 3 below.

[0027]

[Table 3]

From Table 3, it has been confirmed that the protrusion of the anisotropic conductive film can be reduced by forming the common electrode portion of the FPC in a comb-shaped pattern or by cutting out. By combining the methods described above, the protrusion of the electric connection member can be reduced, and therefore, particularly in a thin and compact electrostatic head as shown in FIG. 3, the yield in nozzle plate joining can be significantly improved. .

The present invention is not limited to the above embodiment, and needless to say, various modifications and substitutions can be made within the scope of the claims.

[0030]

As described above, the nozzle substrate on which the nozzles for discharging ink are formed, the liquid chamber communicating with the nozzles, and the vibration plate for applying pressure to the ink in the liquid chamber are formed. It has a diaphragm substrate, an electrode substrate on which individual electrodes are formed facing each other with a small gap between them, and a printed circuit board for applying a voltage to the individual electrodes. The printed circuit board and the electrode substrate are electrically connected. According to the method for manufacturing an ink jet head connected by members, the temperature of the end of the printed circuit board at the press contact surface has a low temperature gradient from above the printed circuit board with the electric connection member interposed between the printed circuit board and the electrode board. Press the crimp head,
It is characterized in that the amount of protrusion of the electrical connection member at the end of the printed board is made smaller than the amount of protrusion of the electrical connection member at the end of the electrode board. In addition, an electric connection member is interposed between the printed board and the electrode board, and the pressure bonding head is tilted so that the height from the printed board end to the electrode board is smaller than the height from the electrode board end to the printed board. Press on the printed circuit board. Therefore, when the printed circuit board is crimped and connected to the electrode substrate with an electric connection member such as a solder or an anisotropic conductive film, the amount of protrusion of the electric connection member on the end side of the printed circuit board is protruded from the end of the electrode substrate. The liquid chamber substrate of the head having a configuration in which the nozzle plate overhangs on the connection portion of the printed circuit board can be easily joined. In a head having a configuration in which the liquid chamber substrate does not overhang on the connection portion of the printed circuit board, the connection portion of the substrate is not rubbed by wiping or the like, so that the connection reliability is improved.

Another feature is an ink jet head manufactured by the above method of manufacturing an ink jet head.

Further, in the ink jet head according to another aspect of the present invention, the amount of protrusion of the electrical connection member at the end of the printed circuit board is smaller than the amount of protrusion of the electrical connection member at the end of the electrode substrate. Therefore, the liquid chamber substrate of the head can be easily joined.

Further, an ink jet head according to still another aspect of the present invention, when a printed board and an electrode board are connected,
The height from the end of the printed circuit board to the electrode substrate is lower than the height from the end of the electrode substrate to the printed circuit board. Therefore, connection reliability is improved.

Another feature of the present invention is that the common electrode formed on the printed circuit board in the ink jet head forms a comb-shaped electrode. Therefore, the electric connection member enters between the combs, and the amount of protrusion to the common electrode side can be reduced.

Another feature of the invention is that an ink jet head is characterized in that a step is provided between an end of a common electrode formed on a printed circuit board and an end of an individual electrode adjacent to the common electrode. Therefore, a large protrusion that adversely affects the assembling process due to an increase in the escape area of the electric connection member can be prevented.

Further, an ink jet recording apparatus according to the present invention includes the above ink jet head.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing a configuration of an ink jet recording apparatus of the present invention.

FIG. 2 is an external view of an inkjet head according to a first embodiment of another invention.

FIG. 3 is a view as viewed from an arrow A in FIG. 2;

FIG. 4 is a sectional view taken along line B-B ′ of FIG. 2;

FIG. 5 is a process diagram when a printed circuit board is connected to an individual electrode.

FIG. 6 is a diagram showing a state in which an electrical adhesive member protrudes when an individual electrode is connected to a printed circuit board.

FIG. 7 is a diagram illustrating a state in which protrusion of an electrical bonding member is controlled when an individual electrode is connected to a printed circuit board.

FIG. 8 is a diagram showing another state in which the protrusion of the electric adhesive member at the time of connection between the individual electrode and the printed board is controlled.

FIG. 9 is a plan view showing an electrode substrate and a diaphragm substrate of the head in this embodiment.

FIG. 10 is a plan view showing an electrode substrate and a diaphragm substrate of a head according to another embodiment.

FIG. 11 is a cross-sectional view illustrating a configuration of a conventional electrostatic ink jet recording apparatus.

[Explanation of symbols]

43; comb-shaped electrode, 44; notch, 51; crimping head,
52; a temperature control member.

Claims (8)

[Claims] A nozzle substrate on which a nozzle for discharging ink is formed, a liquid chamber communicating with the nozzle, and a diaphragm substrate on which a diaphragm for applying pressure to the ink in the liquid chamber is formed. An electrode substrate on which an individual electrode is formed facing the diaphragm with a small gap therebetween, and a printed circuit board for applying a voltage to the individual electrode, and electrically connecting the printed circuit board and the electrode substrate In the method for manufacturing an ink jet head connected by a member, the temperature of the end of the printed circuit board at the press-contact surface is low from above the printed circuit board with the electric connection member interposed between the printed circuit board and the electrode board. A pressing head having a gradient is pressed, and the amount of protrusion of the electrical connection member at the end of the printed circuit board is determined by the electrical connection at the end of the electrode board. A method of manufacturing an ink jet head, which comprises less than the protrusion amount of wood. 2. A nozzle substrate on which a nozzle for discharging ink is formed, a liquid chamber communicating with the nozzle, and a diaphragm substrate on which a diaphragm for applying pressure to the ink in the liquid chamber is formed. An electrode substrate on which an individual electrode is formed facing the diaphragm with a small gap therebetween, and a printed circuit board for applying a voltage to the individual electrode, and electrically connecting the printed circuit board and the electrode substrate In the method for manufacturing an ink jet head connected by a member, the electrical connection member is interposed between the printed board and the electrode board, and the height from the printed board end to the electrode board is set from the electrode board end. A pressure bonding head that is inclined so as to be smaller than the height of the printed circuit board is pressed from above the printed circuit board, and the electrical connection member on the printed circuit board end side is A method of manufacturing an ink jet head, which comprises less than the protrusion amount of the electrical connecting member only out amount in the electrode substrate end portion side. 3. An ink jet head manufactured by the method for manufacturing an ink jet head according to claim 1. 4. A nozzle substrate on which a nozzle for discharging ink is formed, a liquid chamber communicating with the nozzle, and a diaphragm substrate on which a diaphragm for applying pressure to the ink in the liquid chamber is formed. An electrode substrate on which an individual electrode is formed facing the diaphragm with a small gap therebetween, and a printed circuit board for applying a voltage to the individual electrode, and electrically connecting the printed circuit board and the electrode substrate In the ink jet head connected by a member, the amount of protrusion of the electrical connection member on the end side of the printed board is smaller than the amount of protrusion of the electric connection member on the end side of the electrode substrate. 5. A nozzle substrate on which a nozzle for discharging ink is formed, a liquid chamber communicating with the nozzle, and a diaphragm substrate on which a diaphragm for applying pressure to the ink in the liquid chamber is formed. An electrode substrate on which an individual electrode is formed facing the diaphragm with a small gap therebetween, and a printed circuit board for applying a voltage to the individual electrode, and electrically connecting the printed circuit board and the electrode substrate In the inkjet head connected by a member, when the printed board and the electrode board are connected, a height from the printed board end to the electrode board is lower than a height from the electrode board end to the printed board. Characteristic inkjet head. 6. A nozzle substrate on which a nozzle for discharging ink is formed, a liquid chamber communicating with the nozzle, and a diaphragm substrate on which a diaphragm for applying pressure to the ink in the liquid chamber is formed. An electrode substrate on which an individual electrode is formed facing the diaphragm with a small gap therebetween, and a printed circuit board for applying a voltage to the individual electrode, and electrically connecting the printed circuit board and the electrode substrate In the inkjet head connected by a member, the common electrode formed on the printed board forms a comb-shaped electrode. 7. A nozzle substrate on which a nozzle for discharging ink is formed, a liquid chamber communicating with the nozzle, and a diaphragm substrate on which a diaphragm for applying pressure to the ink in the liquid chamber is formed. An electrode substrate on which an individual electrode is formed facing the diaphragm with a small gap therebetween, and a printed circuit board for applying a voltage to the individual electrode, and electrically connecting the printed circuit board and the electrode substrate In the inkjet head connected by a member, a step is provided between an end of the common electrode formed on the printed circuit board and an end of the individual electrode adjacent to the common electrode. 8. An ink jet recording apparatus comprising the ink jet head according to claim 3.