JPH1034920A - Ink jet head - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simply and inexpensively attach an ink jet head with high accuracy. SOLUTION: Two positioning holes 33, 34 are formed to a substrate 11 in order to position a frame member 13 and a spacer member 17 and positioning pins 35, 36 capable of being fitted in the positioning holes 33, 34 of the substrate 11 are provided to the frame member 13 on the side of the bonding surface with the substrate 11 and positioning pins 37, 38 capable of being fitted in the positioning holes 33, 34 of the substrate 11 are also provided to the spacer member 17 on the side of the bonding surface with the substrate 11.

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, and more particularly to an ink-jet head capable of positioning a substrate and a member laminated on the substrate or a member supporting the substrate with high accuracy.

[0002]

2. Description of the Related Art An ink jet recording apparatus has almost no vibration and noise during recording, and is particularly easy to colorize.
In addition to a printer that outputs data from a digital processing device such as a computer, it is also used for facsimile machines, copiers, and the like. An ink jet head used in such an ink jet recording apparatus records an image on a recording medium by ejecting ink droplets from nozzles by driving actuator elements such as a piezoelectric element and a heating resistor in accordance with a recording signal. It is what you do.

In such an ink-jet head, it is necessary to manufacture each component of the head with high precision and to assemble each component with high precision. That is, for example, in a color ink jet recording apparatus that records a color image, the relative displacement of the nozzles of the recording heads for yellow (Y), magenta (M), cyan (C), and black (BK) may be different. If it occurs, it will appear as a color shift directly, and image quality will be degraded. Therefore, it is necessary to install the head of each color at a predetermined position with high precision, and therefore, it is necessary to assemble each component from the nozzle of the inkjet head to the fixing member for fixing the head with high precision.

Therefore, as described in Japanese Patent Application Laid-Open No. 61-61859, for example, a conventional ink jet head includes an orifice plate having an ink discharge port (orifice) and a substrate to which the orifice plate is bonded and bonded. There has been known a method in which an uneven portion for positioning is provided by etching, patterning of a dry film resist or the like, and the two members are aligned by combining and joining the uneven portions.

[0005]

However, since the above-mentioned ink jet head has a structure in which an orifice plate having an orifice (nozzle) formed on a substrate is directly bonded and fixed, for example, a piezoelectric element is arranged on the substrate and An inkjet head having a structure in which a frame member around a piezoelectric element is arranged, and a diaphragm, a flow path forming member for forming a liquid chamber flow path, and a nozzle forming member for forming a nozzle are sequentially laminated on the piezoelectric element and the frame member. Cannot be applied to

The present invention has been made in view of the above points, and has as its object to enable an ink jet head to be assembled easily, at low cost, and with high accuracy.

[0007]

According to a first aspect of the present invention, there is provided an ink jet head having a piezoelectric element disposed on a substrate, and a liquid chamber being pressurized by displacement of the piezoelectric element to form an ink droplet from a nozzle. In the ink jet head that discharges the ink, a positioning hole is provided in one of the substrate and a member disposed on the substrate, and a pin member that can be fitted in the positioning hole is provided in the other.

According to a second aspect of the present invention, in the inkjet head of the first aspect, a liquid chamber supporting member for supporting a liquid chamber forming member for forming the liquid chamber is laminated on the substrate and positioned on the substrate. A hole was formed, and a pin member was provided on the liquid chamber support member.

According to a third aspect of the present invention, there is provided an ink jet head in which a piezoelectric element is disposed on a substrate, and the displacement of the piezoelectric element presses a liquid chamber to discharge ink droplets from a nozzle. The positioning hole is provided in one of the members to be engaged, and a pin member that can be fitted in the positioning hole is provided in the other.

According to a fourth aspect of the present invention, in the inkjet head of the third aspect, the substrate is supported by a head support member, a positioning hole is formed in the substrate, and a pin member is provided in the head support member. .

According to a fifth aspect of the present invention, there is provided an ink jet head according to any one of the first to fourth aspects, wherein a plurality of the positioning holes are provided, and at least one positioning hole is formed in a shape for positioning only in the width direction.

According to a sixth aspect of the present invention, in the inkjet head, a piezoelectric element is arranged on a substrate, and the displacement of the piezoelectric element presses a liquid chamber to discharge ink droplets from a nozzle. A liquid chamber supporting member that supports a liquid chamber forming member that forms a liquid crystal panel is laminated, the substrate is supported by a head supporting member, and a positioning hole is formed in the substrate. The liquid chamber supporting member and the head supporting member include: A pin member that can be fitted into each of the same positioning holes of the substrate is provided.

According to a seventh aspect of the present invention, in the inkjet head of the second aspect, a liquid chamber supporting member for supporting a liquid chamber forming member for forming the liquid chamber is laminated on the substrate and positioned on the substrate. A hole is formed, and an ink supply joint having an ink supply hole for supplying ink to the liquid chamber is formed in the liquid chamber support member so as to be fitted into a positioning hole of the substrate.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION

[0015]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is an exploded perspective view showing an example of an inkjet head to which the present invention is applied. This ink jet head includes a drive unit 1, a liquid chamber unit 2, and a head cover 3.

The drive unit 1 has a plurality of laminated piezoelectric elements 12 joined and arranged in two rows on an insulating substrate 11 made of ceramic, glass epoxy resin or the like. The frame member 13 which is a liquid chamber support member surrounding the periphery is joined. In addition, a common electrode pattern 14 and an individual electrode pattern 15 are provided on the substrate 11, and the common electrode pattern 14 fills a hole 16 provided in the frame member 13 with a conductive adhesive to make each pattern portion conductive. taking it.

The substrate 11 is supported and held on a spacer member (head holder) 17 serving as a head support member, and a PCB substrate having a head driving IC and the like held in the spacer member 17 and each of the drive unit 1 are provided. Piezoelectric element 12
Are connected via an FPC cable 18.

The liquid chamber unit 2 is composed of a vibration plate 21 made of a thin film of metal or resin, flow path forming members 22 and 22 made of a photosensitive resin or the like, and a nozzle forming member made of metal or resin forming the nozzle 24. A certain nozzle plate 23 is formed by laminating and heat-sealing. The surface of the nozzle plate 23 is provided with a water-repellent surface 25 that has been subjected to a water-repellent surface treatment and a non-water-repellent surface 26 that has not been subjected to the water-repellent treatment on the periphery.

The nozzle cover (head cover) 3 is formed in a box shape to cover the peripheral portion of the nozzle plate 23 and the side surface of the head.
An opening is formed corresponding to No. 5 and bonded to the non-water-repellent surface 26 of the nozzle plate 23 with an adhesive.

In order to supply ink from an ink cartridge (not shown) to the liquid chamber, an ink supply hole 27 is provided in the spacer member 17 in the ink jet head provided on the back side of the frame member 13 in the substrate 11. A joint hole 28 through which a joint having an ink supply hole 29 penetrates, and ink supply holes 29 and 30 are provided in the frame member 13 and the vibration plate 21, respectively.

Then, as shown in FIG. 2, the ink jet head H having the above-described parts assembled thereto is fixed by bonding and bonding the spacer member 17 to the L-shaped bracket 31, and is mounted on a carriage or the like of the recording apparatus main body. I do.

Therefore, an embodiment in which the present invention is applied to the ink jet head H will be described with reference to FIGS. 3 is a perspective view showing a state in which the drive unit 1 is joined to the spacer member 17, FIG. 4 is an exploded perspective view for explaining the joining process of FIG. 3, and FIG.

As shown in FIG. 5, through holes are formed in the insulating substrate 11 so as to position the frame member 13 (inverted in FIG. 4) and the spacer member 17 as a liquid chamber supporting member. The two positioning holes 33 and 34 are formed. Positioning pins 35 and 36, which are pin members that can be fitted into positioning holes 33 and 34 of the substrate 11, are provided on the joint surface side of the frame member 13 as the liquid chamber support member with the substrate 11, and similarly, The substrate 11 is also provided on the bonding surface side of the spacer member 17 as the head support member with the substrate 11.
Positioning pins 37 and 38, which are pin members that can be fitted into the positioning holes 33 and 34, are provided. The joint portion 39 having the ink supply hole 29 is provided on the back side of the frame member 13 as described above.

Here, one positioning hole 33 of the substrate 11
Is a round hole, and the positioning pin 35 of the frame member 13 is
The positioning pin 37 of the spacer member 17 also has a circular cross section, and the positioning hole 33 and the positioning pin 3
Reference numerals 5 and 37 are formed with a diameter dimension that can be fitted with high accuracy. The other positioning hole 34 has a long hole shape, the positioning pins 36 and 38 have a circular cross section, and the width dimension of the positioning hole 34 is formed to the outer dimensions of the positioning pins 36 and 38 to be fitted. The positioning of the spacer member 17 in the rotation direction is performed. The length of the positioning hole 34, which is a long hole, is determined by the positioning pin 36,
38 is formed to a size capable of absorbing a relative pitch error with respect to.

Instead of using a combination of a plurality of pins and holes as described above, a shape other than a round hole and a circular pin, such as a combination of a round pin and a long hole, a combination of a square pin and a square hole, etc. Can be adopted. In this case, 1
A combination of individual pins and holes may be provided. However, it is preferable to provide a plurality of such shapes because positioning accuracy may not be sufficiently obtained with respect to component accuracy.

The positioning pin 3 of the frame member 13
5 and 36 and positioning pins 37 and 3 of the spacer member 17
8 are the same positioning holes 33, 34 of the substrate 11, respectively.
, So that it is formed in a length that does not hit the mating pin when fitted. Like this one
By sharing the two positioning holes with two members, the substrate 1
The number of holes provided in 1 can be reduced. However, a configuration in which a positioning hole is provided for each pin can also be adopted.

Therefore, in this ink jet head, an adhesive is applied to at least one surface of the front side of the substrate 11 and the back side of the frame member 13 so that the frame member 1
3 positioning pins 35 and 36 are
Adhesive bonding is performed while inserting and positioning them in 3, 34. Next, an adhesive is applied to at least one surface of the back surface side of the substrate 11 and the front surface side of the spacer member 17 to form the spacer member 1.
7 positioning pins 37 and 38 to the positioning holes 3 of the substrate 11.
The head unit including the substrate 11 and the spacer member 17 are bonded to each other while being inserted into
And assemble. Further, the spacer member 17 is fixed to the above-described L-shaped bracket 31 (a method for fixing to the L-shaped bracket will be described later).

As described above, in this ink jet head, the positioning hole is provided in one of the substrate and the member arranged on the substrate, and the pin which can be fitted in the positioning hole of the substrate is provided in the other. Adhesive bonding can be performed by applying pressure while easily positioning other members, so that it is possible to assemble with high accuracy, and it is possible to reduce the assembly time and cost.

Next, another embodiment will be described with reference to FIG. The joint portion 39 in which the ink supply hole 29 of the frame member 13 is formed passes through the joint portion hole 28 of the substrate 11 and the ink supply hole 2 of the spacer member 17.
7 is fitted and sealed by an O-ring 40. Therefore, in this embodiment, the outer dimension a of the joint 39 of the frame member 13, the inner diameter b of the joint hole 28 of the substrate 11, and the inner diameter c of the ink supply hole 27 of the spacer member 17 are formed to be substantially the same. And the joint 39
Are positioning pins, and the joint portion holes 28 and the ink supply holes 27 also function as positioning holes.

With this arrangement, it is not necessary to provide a special set of positioning holes and pins, so that the number of holes provided in the substrate can be reduced, and positioning can be performed with high precision while securing the strength of the substrate. Become like

Next, referring to FIG. 7 and subsequent figures, an example in which high-precision positioning is performed without using positioning holes and pins unlike the present invention will be described. 7 is a side view of the head assembly according to this embodiment, FIG. 8 is a left side view of FIG. 7, FIG. 9 is a plan view of FIG. 7 viewed from below, and FIG. 10 is an exploded view of the drive unit and the spacer member. FIG. 11 is an exploded perspective view of the spacer member and the L-shaped bracket.

First, the head unit 50 is constructed by joining a frame member on an insulating substrate 51 and joining a liquid chamber unit on this frame member, similarly to the above-described ink jet head H. In this case, the frame member is positioned using a positioning jig with reference to the substrate 51, and is bonded with an adhesive by applying pressure.

The X reference portions 54 and Y, which are higher than the bonding surface for positioning the substrate 51 (head unit 50) at the ends in the X and Y directions of the spacer member 53, respectively.
A reference portion 55 is provided, and as shown in FIG. 10, an adhesive is applied to each of the back surface of the substrate 51 and the surface of the spacer member 53 (portions indicated by diagonal lines in FIG. 10), and the head unit 50 is positioned using a positioning jig. The end surface of the substrate 51 is positioned by contacting the X reference portion 54 and the Y reference portion 55 of the spacer member 53, and is joined with an adhesive.

Further, as shown in FIG. 11, the spacer member 53 is attached to the back surface of the spacer member 53 and the L-shaped bracket 57.
X reference portion 58 higher than the joint surface for positioning
A Y reference portion 59 is provided, and as shown in FIG.
An adhesive is applied to the back surface of the L-shaped bracket 57 and the front surface of the L-shaped bracket 57, respectively, (the hatched portion in the figure). , Y reference portion 59 and are positioned and abutted with an adhesive. The spacer member 53
Also, between the ink supply hole 27 and the L-shaped bracket 58, an O-
The ring 60 is interposed.

Although the positioning accuracy between the components can be improved in this way, when compared with the above-described embodiment of the present invention, the adhesive bonding is performed by further pressing while positioning by pressing against the X and Y standards. This is disadvantageous in terms of accuracy, configuration, cost, and the like, such as complicating the configuration of the bonding jig and the bonding apparatus.

[0036]

As described above, according to the ink jet head of the first aspect, the piezoelectric element is arranged on the substrate,
In an ink jet head that pressurizes the liquid chamber by the displacement of the piezoelectric element and ejects ink droplets from the nozzle, a positioning hole can be fitted to one of the substrate and a member arranged on the substrate, and a positioning hole can be fitted to the other. Since the pin member is provided, the board and the member to be arranged on the board can be easily positioned with high accuracy, and the assembling accuracy is improved, and the jig and the joining device for joining are simplified, and the assembling time is reduced. Can also be shortened,
Costs are also reduced.

According to the ink jet head of the second aspect, in the ink jet head of the first aspect, the liquid chamber supporting member for supporting the liquid chamber forming member for forming the liquid chamber is laminated on the substrate, and the positioning hole is formed in the substrate. And a pin member is provided on the liquid chamber support member, so that the substrate and the liquid chamber support member can be easily positioned with high precision, and assembling accuracy is improved. It ’s easy,
Assembly time can be reduced, and costs can be reduced.

According to the ink jet head of the third aspect, in the ink jet head in which a piezoelectric element is disposed on a substrate and the liquid chamber is pressurized by displacement of the piezoelectric element to discharge ink droplets from a nozzle, the substrate and the substrate are connected to each other. Since the positioning hole is provided on one of the supporting members and the pin member which can be fitted into the positioning hole is provided on the other, the substrate and the member supporting the substrate can be easily positioned with high precision and assembled. The accuracy is improved, the jig and the joining device for joining are simplified, the assembling time can be shortened, and the cost is reduced.

According to the ink jet head of claim 4, in the ink jet head of claim 3, the substrate is supported by the head support member, the positioning hole is formed in the substrate, and the pin member is provided in the head support member. ,
The substrate and the head support member can be easily positioned with high accuracy, and the assembling accuracy is improved, the jig and the joining device for joining are simplified, the assembling time can be reduced, and the cost can be reduced.

According to a fifth aspect of the present invention, in the inkjet head of the first aspect, a plurality of positioning holes are provided, and at least one positioning hole is provided.
Since the positioning holes are formed in a shape for positioning only in the width direction, the positioning can be performed more easily.

According to a sixth aspect of the present invention, there is provided an ink jet head in which a piezoelectric element is disposed on a substrate, and the displacement of the piezoelectric element presses the liquid chamber to discharge ink droplets from nozzles. A liquid chamber supporting member for supporting a liquid chamber forming member is formed, a substrate is supported by a head supporting member, a positioning hole is formed in the substrate, and the liquid chamber supporting member and the head supporting member have the same substrate. Since pin members are provided to fit into the positioning holes,
The substrate, the liquid chamber support member and the head support member can be easily positioned with high precision, and assembling accuracy is improved, the jig and the joining device for joining are simplified, the assembling time can be reduced, and the cost can be reduced. The number of positioning holes provided in the substrate can be further reduced, and the positioning accuracy can be obtained while securing the strength of the substrate.

According to the ink jet head of the seventh aspect, in the ink jet head of the second aspect, a liquid chamber supporting member for supporting a liquid chamber forming member for forming a liquid chamber is laminated on the substrate, and a positioning hole is formed in the substrate. The ink supply joint having an ink supply hole for supplying ink to the liquid chamber is formed in the liquid chamber support member so as to be fitted into the positioning hole of the substrate, so that the number of positioning holes provided on the substrate is reduced. The positioning accuracy can be obtained while securing the strength of the substrate.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing an example of an inkjet head to which the present invention is applied.

FIG. 2 is a perspective view of a head assembly.

FIG. 3 is an explanatory perspective view of a state where a drive unit and a spacer member are joined.

FIG. 4 is an exploded perspective view of a drive unit and a spacer member.

FIG. 5 is an enlarged exploded sectional view of a main part of FIG. 4;

FIG. 6 is an exploded sectional view of a main part showing another example of the present invention.

FIG. 7 is a front view of a head assembly that does not use the present invention.

FIG. 8 is a left side view of FIG. 7;

FIG. 9 is a plan view seen from below in FIG. 7;

FIG. 10 is an exploded perspective view of a head unit and a spacer member.

FIG. 11 is an exploded perspective view of a spacer member and an L-shaped bracket.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Drive unit, 2 ... Liquid chamber unit, 3 ... Nozzle cover, 11 ... Substrate, 13 ... Frame member, 17 ... Spacer member, 33, 34 ... Positioning hole, 35, 36, 37, 3
8 ... Positioning pin member, 31 ... L-shaped bracket.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Hideyuki Makita 1-3-6 Nakamagome, Ota-ku, Tokyo Inside Ricoh Company (72) Inventor Tsutomu Sasaki 1-3-6 Nakamagome, Ota-ku, Tokyo Share Inside the company Ricoh

Claims (7)

[Claims] 1. An ink jet head in which a piezoelectric element is disposed on a substrate and a liquid chamber is pressurized by displacement of the piezoelectric element to discharge ink droplets from a nozzle, wherein the substrate and a member disposed on the substrate are disposed. An ink jet head comprising: a positioning hole provided on one side; and a pin member fittable into the positioning hole on the other side. 2. The ink jet head according to claim 1, wherein a liquid chamber supporting member for supporting a liquid chamber forming member for forming the liquid chamber is laminated on the substrate, and a positioning hole is formed in the substrate. An ink jet head, wherein a pin member is provided on the liquid chamber support member. 3. An ink jet head in which a piezoelectric element is arranged on a substrate and a liquid chamber is pressurized by displacement of the piezoelectric element to eject ink droplets from a nozzle, and the substrate or one of members supporting the substrate is provided. An ink jet head comprising: a positioning hole; and a pin member that can be fitted into the positioning hole. 4. The ink jet head according to claim 3, wherein the substrate is supported by a head support member, a positioning hole is formed in the substrate, and a pin member is provided on the head support member. Ink jet head. 5. The ink jet head according to claim 1, wherein a plurality of the positioning holes are provided, and at least one positioning hole is formed in a shape for positioning only in the width direction. head. 6. An ink jet head in which a piezoelectric element is arranged on a substrate, and a liquid chamber is pressurized by displacement of the piezoelectric element to discharge ink droplets from a nozzle, wherein a liquid chamber is formed on the substrate. Laminating a liquid chamber supporting member supporting the member, and supporting the substrate with a head supporting member,
An ink jet head, wherein a positioning hole is formed in the substrate, and a pin member is provided in the liquid chamber supporting member and the head supporting member so as to fit into the same positioning hole of the substrate. 7. The ink jet head according to claim 2, wherein a liquid chamber supporting member that supports a liquid chamber forming member that forms the liquid chamber is laminated on the substrate, and a positioning hole is formed in the substrate. An ink jet head, wherein an ink supply joint having an ink supply hole for supplying ink to the liquid chamber is formed on the liquid chamber support member so as to fit into a positioning hole of the substrate.