JP2001146013A - Ink-jet head, head unit and ink-jet recording device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To achieve high integration and high density at a low cost by achieving easy electric connection and improving the reliability. SOLUTION: A plurality of input terminal parts 16, 17 are provided in an FPC 5 connected with a control signal input terminal part such that a control signal for ejecting ink droplets can be inputted by using either of the input terminals 16, 17 so as to improve the freedom of the control signal input part.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet head, a head unit, and an ink jet recording apparatus.

[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 ink jet recording method capable of high-speed recording and capable of performing recording on plain paper without requiring a special fixing process is an extremely effective method, and various methods have been conventionally proposed, commercialized and put to practical use. Such an ink jet recording method is to perform recording by flying small droplets of ink as a recording liquid and attaching the droplets to a recording medium, and to control a method of generating the droplets of the recording liquid and a flying direction of the droplets. Are roughly divided into several types according to the control method.

The first method is disclosed in, for example, US Pat.
No. 429. This is called a teletype method, in which small droplets of a recording liquid are electrostatically attracted, the generated small droplets are subjected to an electric field control according to a recording signal, and the small droplets are placed on a recording medium. The recording is performed by selectively attaching the recording medium. In particular,
An electric field is applied between the nozzle and the accelerating electrode to cause a uniformly charged droplet of the recording liquid to be ejected from the nozzle, and the ejected droplet to be electrically controlled in accordance with the recording signal. The droplet is caused to fly, and small droplets are selectively deposited on the recording medium by a change in the intensity of the electric field.

The second system is disclosed in, for example, US Pat.
No. 275, U.S. Pat. No. 3,298,030, and the like. This is a sweet (Sw
Eet) method, which generates droplets of the recording liquid whose charge amount is controlled by the continuous vibration generation method, and flies the droplets whose charge amount is controlled between the deflection electrodes to which a uniform electric field is applied. Thus, recording is performed on the recording medium.
Specifically, an orifice (ejection port) of a nozzle which is a part of a recording head provided with a piezoelectric vibrating element
The charging electrodes to which the recording signal is applied are separated by a predetermined distance before and a constant frequency electric signal is applied to the piezoelectric vibrating element to mechanically vibrate the piezoelectric vibrating element and record from the orifice. Discharge droplets of liquid.
At this time, a charge is electrostatically induced in the discharged droplet by the charging electrode, and the droplet is charged with a charge amount corresponding to the recording signal.
When the droplet having a controlled charge amount flies between the deflection electrodes to which a constant electric field is uniformly applied, the droplet is deflected according to the added charge amount, and only the droplet carrying the recording signal remains on the recording medium. It will adhere.

A third method is disclosed in, for example, US Pat.
No. 153 specification. This method is called a Hertz method, in which an electric field is applied between a nozzle and a ring-shaped charging electrode, and recording is performed by generating and atomizing small droplets of a recording liquid by a continuous vibration generation method. That is, by modulating the intensity of the electric field applied between the nozzle and the charging electrode in accordance with the recording signal, the atomization state of the droplet is controlled, and the gradation of the recording image is obtained and recorded.

A fourth method is disclosed in, for example, US Pat.
No. 120 is disclosed. This is called a Stemme method, and has a fundamentally different principle from the first to third methods. That is, all of the first to third methods electrically control the droplets of the recording liquid ejected from the nozzles while they are flying, and selectively deposit the droplets carrying the recording signal on the recording medium. On the other hand, in the Stemme method, recording is performed by ejecting and flying small droplets of a recording liquid from an ejection port in accordance with a recording signal. That is, the Stemme method is:
An electric recording signal is applied to a piezoelectric vibrating element (piezoelectric element) attached to a recording head having a discharge port for discharging a recording liquid to change the vibration into mechanical vibration of the piezoelectric vibrating element, and discharge according to the mechanical vibration. The droplet of the recording liquid is ejected from the outlet to fly and adhere to the recording medium.

[0007] Each of these four methods has its own features,
Each has its disadvantages. The first method is simple in structure, but requires a high voltage to generate small droplets of the recording liquid, and is not suitable for high-speed recording because it is difficult to use a multi-nozzle recording head. The second method enables multi-nozzle recording heads and is suitable for high-speed recording. However, the configuration is complicated and the electrical control of small droplets of the recording liquid is advanced and difficult. Tends to occur. The third method makes it possible to perform recording with excellent gradation by atomizing small droplets of the recording liquid, but it is difficult to control the atomization state.
Further, fogging occurs in a recorded image, and it is difficult to form a multi-nozzle recording head, which is not suitable for high-speed recording. On the other hand, the fourth method has a simple configuration, and in order to perform recording by discharging the recording liquid from the discharge port of the nozzle on demand, the droplets ejected and flying like the first to third methods are used. In addition, there is no need to collect small droplets not required for image recording. Further, unlike the first and second systems, there is no need to use a conductive recording liquid, and there is an advantage that the degree of freedom of the recording liquid in terms of material is large. However, on the other hand, it is difficult to make the recording head a multi-nozzle because the size of the piezoelectric vibrator required for ejection is large and it is extremely difficult to reduce the size of the piezoelectric vibrating element.

[0008] These disadvantages are described, for example, in Japanese Patent Laid-Open No. 6-320.
No. 721, a plurality of piezoelectric element rows are provided on a substrate, and a drive pulse is applied to each piezoelectric element row to change the volume of a pressurized liquid chamber connected to a nozzle, thereby discharging ink droplets from the nozzle. As described in JP-A-7-246706, a plurality of nozzles, an ink flow path communicating with the nozzles, a diaphragm formed in a part of the flow path, This problem is solved by applying an electric pulse between the vibration plate and the electrode, deforming the vibration plate by electrostatic force, and ejecting ink droplets from each nozzle.

The printing method of the ink jet recording apparatus can be roughly classified into a serial type (shuttle type) and a line type. The serial type uses a head with a small number of nozzles,
One line is printed with the recording medium stopped, and then the next one line is printed by sending the recording medium. On the other hand, in the line type, recording is performed while continuously feeding the recording medium with nozzles corresponding to the width of the recording medium. Generally, a serial type head is easier to make, and almost all types of heads currently on the market are commercially available. On the other hand, it is more difficult to produce a long head with high reliability, so that a plurality of heads are arranged side by side when forming a line type head. For example, in a bubble jet (thermal ink jet), a line type head is realized by this method.

In the case of the bubble jet, since a silicon substrate is used as a head substrate, a drive circuit can be formed on the silicon substrate by a semiconductor process, and a control element can be provided integrally with the head. Therefore, the number of input signals to the head may be much smaller than the number of nozzles, and wire bonding is used as a signal input method in terms of reliability and cost. The same applies to the case of a line type. However, in the case of a recording method using a piezoelectric element, since the piezoelectric element is formed on a substrate such as a ceramic substrate, it is difficult to integrally form the control element. Therefore, the control element is formed on a printed circuit board (PCB) separately from the head. In this case, P
In order to connect the CB substrate and the head, signal lines of the number of actuators (usually equal to the number of nozzles) formed by the piezoelectric elements are required. When wire bonding is used as this connection method, an enormous number of connections must be performed one by one in a line type head, which increases the cost. For example, in the case of a line type head having a length of 150 dpi and an A4 short direction, 1100 or more electrode connections are performed.

In order to solve this problem, see, for example, JP-A-6-3
As disclosed in JP-A-20721 and JP-A-7-246706, a drive electrode portion of a head and a flexible printed wiring board (FPC) are connected by solder or anisotropic conductive tape. This method is excellent as a low-cost connection method because all the electrodes can be connected at once. Furthermore, since connection of a plurality of electrodes can be performed at once, there is an advantage that the connection time is short and the connection cost is low.

[0012]

However, when this connection method is used for a line type head, the FPC itself becomes large, so that the yield at the time of manufacturing the FPC decreases. Further, since the length of the electrode pattern of the FPC in the arrangement direction becomes longer, the cumulative arrangement error of the pattern becomes larger, and the position of the head with respect to the piezoelectric element or the electrode connected to the piezoelectric element is shifted. Further, when the size of the FPC itself increases, the heating head of the crimping device for thermocompression bonding of the solder and the anisotropic conductive tape increases, and the crimping device itself becomes disadvantageous in size.

The present invention improves such disadvantages, and provides a low-cost, high-integration and high-density ink-jet head which can be easily electrically connected and has high reliability, and a head unit and an ink-jet recording apparatus using the same. It is intended to do so.

[0014]

An ink jet head according to the present invention sprays ink droplets directly on a recording medium by a control signal input from an input terminal of a printed wiring board connected to a control signal input terminal to form characters or characters. In an ink jet head for drawing an image, a printed wiring board connected to a control signal input terminal has a plurality of input terminals.

It is preferable that a plurality of input terminal portions of the printed wiring board are arranged at positions facing each other with an output terminal portion connected to a control signal input terminal portion interposed therebetween.

Further, the arrangement pitch of the plurality of input terminals constituting the plurality of input terminal portions of the printed wiring board may be made equal, or the plurality of input terminals constituting the plurality of input terminal portions of the printed wiring board may be arranged in the same arrangement pattern. It is good to arrange.

The head unit according to the present invention is characterized in that at least two sets of the ink jet heads are joined to each other so that the input terminals of the printed wiring boards are close to each other.

An ink jet recording apparatus according to the present invention includes the head unit and receives a control signal from an input terminal adjacent to a printed wiring board.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In an ink jet head (hereinafter referred to as a head) of the present invention, a liquid chamber substrate, a diaphragm substrate and an electrode substrate are bonded and laminated by a direct bonding method such as an adhesive or anodic bonding. An FPC, which is a printed wiring board, is connected to the electrodes. The liquid chamber substrate is provided with a plurality of nozzles. The vibration plate substrate has a vibration plate, a liquid chamber communicating with a nozzle is formed by a liquid chamber substrate and a vibration plate of the vibration plate substrate, and a common liquid chamber communicating with each liquid chamber is formed by the liquid chamber substrate and the vibration plate substrate. Has formed. The electrode substrate has individual electrodes provided opposite the diaphragm at a fixed interval. Each individual electrode is connected to the electrode lead provided on the FPC substrate and solder or anisotropic conductive material. They are connected by a connection member made of a conductive film.

The FPC connected to each individual electrode has two sets of input terminals having a plurality of input terminals and an output terminal having a plurality of output electrodes connected to the individual electrodes on the same surface of the FPC. The two sets of input terminal portions are formed, for example, at positions facing each other with the output terminal portion interposed therebetween.

The head unit is formed by bonding two sets of electrode substrates to each other. The same surface of the FPC of each head of the formed head unit faces each other, and different input terminal portions are adjacent to each other on the right and left sides. By inputting a control signal using one of the left and right input terminal portions adjacent to each other, only one place for supplying the control signal needs to be provided, and the circuit configuration of the control signal input to the head unit is reduced. Simplify.

[0022]

FIG. 1 is a perspective view showing the appearance of an ink jet head according to an embodiment of the present invention. As shown in the figure, an ink-jet head (hereinafter referred to as a head) 1 has a liquid chamber substrate 2, a diaphragm substrate 3 and an electrode substrate 4 bonded and laminated by a direct bonding method such as an adhesive or anodic bonding. FPC5 which is a printed wiring board is connected to the electrodes. The liquid chamber substrate 2 is provided with a plurality of nozzles 6 as shown in FIG. The diaphragm substrate 3 has a diaphragm 7 as shown in the cross-sectional view of FIG.
The liquid chamber 8 communicating with the nozzle 6 is formed by the liquid chamber substrate 2 and the vibration plate 7 of the vibration plate substrate 3, and the common liquid chamber 9 communicating with each liquid chamber 8 is formed by the liquid chamber substrate 2 and the vibration plate substrate 3. ing. Electrode substrate 4
Has individual electrodes 10 provided opposite to the vibration plate 7 at a fixed interval. Each individual electrode 10 is connected to an electrode lead 12 provided on a substrate 11 of the FPC 5 and a solder or a conductive material. They are connected by a connection member 13 made of an anisotropic conductive film.

The liquid chamber substrate 2 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 3 to form a nozzle 6, a liquid chamber 8 and a common liquid chamber 9. Can be formed.
As a material of the liquid chamber substrate 2, a metal such as stainless steel, a semiconductor such as Si, or an insulating material such as glass is used. When a conductive material such as metal or Si is used, it is preferable to connect the liquid chamber substrate 2 to the ground in order to drop the ink inside to the ground level. The ejection surface of the nozzle 6 is subjected to a water-repellent treatment by a known method such as plating or a water-repellent agent coating in order to ensure water-repellency with the ink.

The diaphragm substrate 3 is made of metal such as stainless steel or S
It is preferable to use a semiconductor such as i. By etching these materials, a fine pattern with a desired thickness can be accurately formed, and the diaphragm substrate 3 itself can be used as a common electrode. When an insulating material such as glass is used, Al, Cu,
A common electrode can be formed by depositing a metal such as Cr, Ni, or Au by vapor deposition or sputtering.

The electrode substrate 4 is formed by etching a metal such as stainless steel, glass, Si or the like to form a groove having a desired depth. An electrode material such as Ni, Al, Ti / Pt, or Cu is formed on the surface to a desired thickness by a film forming technique such as sputtering, CVD, or vapor deposition, and then a photoresist is formed and etched. An individual electrode 10 is formed in each groove. When a metal is used for the electrode substrate 4, an insulating layer is formed thereon using an insulating material such as a resin or SiO _2, and the individual electrodes 10 are formed thereon. An insulating layer made of SiO ₂ or the like may be formed on the individual electrode 10 to prevent the electrode from being damaged by a short circuit or discharge.

The substrate 11 of the FPC 5 which is a printed wiring board
A plate-shaped printed board made of glass epoxy resin, phenol resin, or the like, or a film-shaped printed board made of polyimide resin, PET resin, or the like is used. As a method of electrically connecting the electrode leads 12 formed on the substrate 11 and the electrode pads of the individual electrodes 10, for example,
There are a method of thermocompression bonding of solder, a method of thermocompression bonding with an anisotropic conductive adhesive, a method of press-contacting electrodes, and a wire bonding method. In the wire bonding method, since the electrodes are directly connected to each other with a metal wire, the connection resistance is low and the reliability is high. The method of thermocompression bonding of solder, the method of thermocompression bonding with an anisotropic conductive adhesive, and the method of press-contacting between electrodes can be performed at the same time because multiple electrodes can be connected at once, making processing easy and low cost. This is an excellent method. Among these, the thermocompression bonding of solder or anisotropic conductive film adheres the substrates after the compression bonding, so there is no need to worry about the connection part being removed in subsequent processing, assembly or printing operation, and it is particularly excellent in terms of reliability. The connection method.

In this connection method, for example, when an anisotropic conductive film is used, the anisotropic conductive film is obtained by dispersing conductive particles called filler in a thermoplastic resin or a thermosetting resin. Heating and pressurizing between the electrodes causes the anisotropic conductive film to be crushed and the filler to come into contact with both electrodes to establish conduction between the electrodes. Using this anisotropic conductive film, for example, as shown in FIG.
Anisotropic conductive film 13 on the end of electrode lead 12 of substrate 11
Are aligned and then temporarily press-bonded to bring the FPC 5 and the anisotropic conductive film 13 into close contact with each other. Then, as shown in (b),
The protective film of the anisotropic conductive film 13 is removed, and the electrode pad portion at the end of the individual electrode 10 of the electrode substrate 4 and the electrode lead 12 of the FPC 5 are aligned, as shown in FIG.
The heated pressure bonding head 14 is pressed against the electrode region from above the FPC 5 to perform thermocompression bonding. In this manner, the electrode leads 12 of the substrate 11 of the FPC 5 and the individual electrodes 10 of the electrode substrate 4 can be easily connected.

FIGS. 5 and 6 show examples of the structure of the FPC 5 connected to the individual electrodes 10 of the electrode substrate 4 as described above. 5 and 6 show a contact surface side with the individual electrode 10. As shown in FIGS. 5 and 6, the FPC 5 includes an input terminal portion 16 having a plurality of input terminals 15 and a plurality of input terminals 15. The input terminal 17 having a plurality of output electrodes 18 connected to the individual electrodes 10 of the electrode substrate 4 has an output terminal 19 having an FPC 5
On the same surface. Then, the FPC 5 shown in FIG.
a and an FPC 5c shown in FIG. 6 (a), which inputs an input signal as it is to the individual electrode 10 of the electrode substrate 4 as an output signal, and a pattern is formed on both surfaces of the substrate 11, and a surface pattern 20 indicated by a solid line. And the back surface pattern 21 indicated by a broken line is connected by a through hole 22. FIG.
The FPC 5b shown in FIG. 6B and the FPC 5d shown in FIG.
Mounts a drive IC 23 for control on the substrate 11 and
The input terminal and the output terminal of C23 are connected to the surface pattern 20 by wire bonding. In FIG. 5B and FIG. 6B, reference numeral 24 denotes a wire bonding pad formed on the surface pattern 20 of the FPC. The FPCs 5a to 5d have output electrodes 18 of 10 for simplicity.
In this example, five control signals are input to the FPCs 5b and 5d using the driving IC 23. Also, FPCs 5a and 5b shown in FIG. 5 are cases where input terminal portions 16 and 17 in which a plurality of input terminals 15 are formed are formed on the same side of the substrate 11, and FPCs 5c and 5d shown in FIG. Reference numeral 15 denotes a case where a plurality of input terminal portions 16 and 17 are formed at positions facing each other with the output terminal portion 19 interposed therebetween.

By connecting any one of the FPCs 5a to 5d having the two sets of input terminal portions 16 and 17 to the individual electrodes 10 of the electrode substrate 4, the input terminal portions 16 and 17
In either case, a control signal can be input to the head 1.

For example, the FPC 5d shown in FIG. 6B is mounted on the individual electrode 10 of the electrode substrate 4 using the anisotropic conductive film 13. The diaphragm plate 3 of the head 1 on which the FPC 5d is mounted has a diaphragm 7 having a thickness of 5 μm formed by etching 0.5 mm thick Si. The electrode substrate 4 has a depth of 0.5
0.14mm width and 0.169m pitch at the bottom of μm groove
m individual electrodes 10 of TiN are formed, and a film thickness of 1
An insulating layer of SiO ₂ of 2,000 ° was formed. The diaphragm substrate 3 and the electrode substrate 4 are bonded with an adhesive, and the liquid chamber substrate 2 is bonded onto the vibration substrate 3 so that the width of the liquid chamber 8 is 0.13 mm.
2.0mm depth, 0.169mm pitch (150d
The head 1 of pi) was formed. Nozzle 5 of this head 1
Has a height of 20 μm and the number of nozzles is 192 channels.

An anisotropic conductive film (three bond 3370C, film thickness 35 μm) 13 is applied to the end of the individual electrode 10 of the head 1.
Were preliminarily crimped. The temporary crimping is performed by setting the temperature of the crimping head of the crimping machine to 150 ° C. and the crimping pressure to 2.94 × 10 ^3.
kPa and the pressure bonding time were 1 second. Furthermore, this FPC
The final pressure bonding is performed with the output terminal portion 19 of the 5d electrode lead 12 being aligned with the electrode pad at the end of the individual electrode 10 of the head 1, and the FPC 5a is mounted on the electrode substrate 4 as shown in the perspective view of FIG. Connected. The final bonding was performed at a temperature of the bonding head of 150 ° C., a pressing force of 2.94 × 10 ³ kPa, and a bonding time of 20 seconds. As a result, the individual electrode 10 and the output terminal portion 19 of the FPC 5 d are bonded by the anisotropic conductive film 13, and the individual electrode 1 is connected to the FPC 5 d and the anisotropic conductive film 13.
The drive voltage can be supplied to 0. The control I
As C23, an IC having 192 channel outputs and 10 input signals was used.

The ink can be supplied from the ink tank through an ink supply port communicating with the common liquid chamber 9 of the head 1. Two heads 1 are used to increase the printing speed by increasing the density and integration of the heads. The nozzle arrangement pitch is 84.6 μm (300 dpi) and the number of nozzles is 384.
Head units were created. At this time, the narrower the interval between the nozzle rows, the smaller the width in the main scanning direction, which is a direction perpendicular to the nozzle rows, and the smaller the printer. Further, since the positions between the nozzle rows need to be attached with high accuracy, as shown in the perspective view of FIG. 8, the electrode substrates 4 with relatively high accuracy are joined together to form a head unit, or the liquid chamber is formed. The substrates 2 are formed by bonding. This head unit is configured using a manifold formed with a hollow ink supply chamber connected to an ink supply pipe (ink supply means) as a base material. A recording head chip is fixed to the top of the manifold, and ink supplied from an ink supply pipe is guided to the top of the manifold through an ink supply chamber, and each head 1 is supplied from an ink supply port provided at an end of the recording head chip. Are supplied to the common flow path, and thereafter, are transported to the respective energy application sections by capillary action of the respective ink supply channels.

For example, as shown in FIG. 8, when the electrode units 4 are joined together to form a head unit, two FPs are formed.
C5d has the same surface facing each other. Therefore, two F
The PC 5d has adjacent input terminal portions 16 and 17 different from each other on the left and right in FIG. This adjacent input terminal unit 1
By inputting a control signal using one of the left and right of the control signals 6, 17, a place for supplying the control signal may be provided in one place. Therefore, the circuit configuration of the control signal input to the head unit can be simplified, and the cost can be reduced. Further, when forming the head unit, there is no need to create two different types of FPCs, and the cost of the FPC can be reduced.

The ink supplied to the ink supply port from the ink supply pipe of the head unit formed as described above is filled in the common liquid chamber 9 and the liquid chamber 8 of each head 1 through the common flow path. When the individual electrodes 10 of each head 1 are individually energized according to the image information, the individual electrodes 1
Electrostatic force is generated between 0 and the diaphragm 7, and the diaphragm 7 is displaced toward the individual electrode 10. Next, when the power is turned off, the diaphragm 7 attempts to return to the original state. At this time, due to a sudden change in the volume of the liquid chamber 8, the ink flies from the nozzle 6 as droplets. For example, a driving voltage of 40 V and a pulse width of 15 μs
c, each head 1 under a driving condition of a continuous driving frequency of 10 kHz.
As a result, a high quality and good image could be formed. The input terminal sections 16 and 17 are connected to the output terminal section 19.
By using the FPCs 5d formed at positions facing each other with respect to, the head unit in which two heads 1 are combined can be reduced in size. Further, the input terminal section 16,
By equalizing the arrangement pitch of the input terminals 15 forming the component 17, the terminal width of the external substrate to be connected can be reduced, the size of the external substrate can be reduced, and the cost can be reduced.

For example, as a connection method for connecting an input terminal of an FPC and a terminal of an external board such as a main board or a relay board, one of the input terminal of the FPC and the terminal of the external board is used. The so-called dimple connection is a method of making an embossed shape to make electrical connection by pressing against the other electrode terminal. This is advantageous in that maintenance can be easily performed since the substrates can be detached from each other at the connection portion, and is often used in low-cost printers. When this embossing is performed, a high-precision jig that is extruded to form a projection on the connection terminal is required. FPC5
As shown in FIG. 9, for example, as shown in FIG. 9, when the input terminals 15 of the input terminal portions 16 and 17 formed at positions facing each other with the output terminal portion 19 interposed therebetween are asymmetrically arranged,
In order to emboss 17 respectively, it is necessary to emboss using a different jig. On the contrary,
As shown in FIG. 10, by arranging the input terminals 15 of the input terminal portions 16 and 17 in the same arrangement pattern, the input terminal portions 16 and 17 can be embossed using one jig. In addition, embossing can be performed at low cost.

A head unit in which one of the FPCs 5a to 5d having two sets of input terminals 16 and 17 is connected to the individual electrodes 10 of the electrode substrate 4 of the head 1 and two heads 1 are combined. By using this in printers, facsimile machines, and copiers, it is possible to reduce the size and cost of printers and the like, and to stably form high-density, high-quality images.

[0037]

As described above, according to the present invention, since a plurality of input terminals are provided on a printed wiring board connected to a control signal input terminal, ink droplets are ejected regardless of which input terminal is used. Control signal to be input,
The degree of freedom of the control signal input section can be increased.

Further, by arranging a plurality of input terminal portions of the printed wiring board at positions opposed to each other across an output terminal portion connected to the control signal input terminal portion, the printed wiring board can be reduced in size and a plurality of nozzles can be formed. Can be downsized.

Further, by forming the head unit by joining at least two sets of the input terminal portions of the printed wiring boards in close proximity to each other, the ink jet head can use any one of the adjacent input terminal portions of each joined head. A control signal can be input, and only one place for supplying the control signal needs to be provided. The circuit configuration of the control signal to be input to the head unit can be simplified, and the cost can be reduced. .

Further, when forming the head unit, there is no need to prepare two different types of printed wiring boards, and the cost of the printed wiring boards can be reduced.

Further, by equalizing the arrangement pitch of the plurality of input terminals constituting the plurality of input terminal portions of the printed wiring board, the circuit configuration of the control signal input to the head unit can be further simplified.

Further, by arranging a plurality of input terminals constituting the plurality of input terminals of the printed wiring board in the same arrangement pattern, each input terminal can be embossed using one jig. And embossing can be performed at low cost.

Further, by using at least two sets of ink jet heads in close proximity to the input terminals of the printed wiring board and using the head unit in a recording device such as a printer, a facsimile, a copying machine, etc., the recording device can be downsized. Cost can be reduced, and a high-density, high-quality image can be stably formed.

[Brief description of the drawings]

FIG. 1 is a perspective view showing the appearance of an ink jet head.

FIG. 2 is a front view showing a nozzle surface of the inkjet head.

FIG. 3 is a cross-sectional view illustrating a configuration of an inkjet head.

FIG. 4 is a process chart when an FPC is connected to an individual electrode.

FIG. 5 is a configuration diagram of an FPC according to an embodiment of the present invention.

FIG. 6 is a configuration diagram of another FPC according to the embodiment of the present invention.

FIG. 7 is a perspective view of an ink jet head to which the FPC of the embodiment is connected.

FIG. 8 is an exploded perspective view showing a configuration of a head unit.

FIG. 9 is a configuration diagram of an FPC when input terminals of an input terminal unit are arranged asymmetrically.

FIG. 10 is a configuration diagram of an FPC in which input terminals of an input terminal unit are arranged in the same arrangement pattern.

[Explanation of symbols]

1; head 2, liquid chamber substrate, 3; diaphragm substrate, 4; electrode substrate, 5; FPC, 6; nozzle, 7; diaphragm, 8; liquid chamber, 9; common liquid chamber, 10; 11; substrate, 1
2; electrode lead, 13; connection member, 15; input terminal, 1
6; input terminal section; 17; input terminal section; 18; output terminal section.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2C057 AF35 AF93 AG07 AG12 AG82 AG85 AG89 AG90 AG92 AG93 AP02 AP13 AP25 AP52 AP53 AP54 AP60 AQ01 AQ03 AQ06 BA03 BA14

Claims (6)

[Claims] An ink jet head for drawing characters and images by directly spraying ink droplets on a recording medium by a control signal input from an input terminal of a printed wiring board connected to a control signal input terminal. An ink jet head having a plurality of input terminal sections on a printed wiring board connected to the section. 2. The ink jet head according to claim 1, wherein the plurality of input terminal portions of the printed wiring board are arranged at positions facing each other across an output terminal portion connected to a control signal input terminal portion. 3. The ink jet head according to claim 1, wherein an arrangement pitch of the plurality of input terminals constituting the plurality of input terminal portions of the printed wiring board is equal. 4. The ink jet head according to claim 1, wherein a plurality of input terminals constituting a plurality of input terminal portions of the printed wiring board are arranged in the same arrangement pattern. 5. A head unit, wherein at least two sets of the ink jet heads according to claim 1 are joined to each other with input terminal portions of printed wiring boards close to each other. 6. An ink jet recording apparatus having the head unit according to claim 5, wherein a control signal is inputted from an adjacent input terminal of a printed wiring board.