JP2003025564A - Ink jet head - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ink jet head in which dust and ink adhering to a nozzle plate are wiped off without stripping the nozzle plate. SOLUTION: A nozzle plate 12 is provided with bonding regions 12c and 12d being folded to cover the outer side faces 9c and 9d at an actuator section 9 in the direction intersecting the front end face. Since the nozzle plate 12 has no level difference on the ejection face, ink and dust adhering thereto can be removed effectively. Furthermore, the nozzle plate 12 is not stripped easily because it is bonded to the actuator section 9 even at the bonding regions 12c and 12d.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inkjet head, and more particularly, to an inkjet head in which the nozzle plate is less likely to come off.

[0002]

2. Description of the Related Art Among recording devices used in printers, copiers, facsimiles and the like, an inkjet recording device (inkjet recording device) is a device for ejecting ink from a recording actuator to perform recording on a recording material. is there.
This inkjet recording device can record high-definition images at high speed, can record plain paper without any special treatment, and can easily record color images using multicolor inks. It has advantages such as low running cost and less noise due to the non-impact method. Among them, the line type using the full multi type recording actuator in which a large number of ejection ports are arranged in the paper width direction can further increase the speed of recording. As recording materials, in addition to paper and resin thin plates (OHP, etc.), in recent years, various recording materials have been used, from thin paper and processed paper to glass, plastic, and metal. It was

FIG. 7 shows the structure of a conventional piezoelectric ink jet head. In this piezoelectric inkjet head, a plurality of channels 1 are formed, and a base 5 made of a piezoelectric element in which electrodes 4 are arranged along a partition wall 2 between the channels 1 to a wire bonding region 3 behind the channels.
And the cover 7 made of the same material as the base 1 on which the ink supply holes 6 are formed, or made of glass, ceramics, resin material, or the like, are attached to each other to form an actuator portion 9 having a pressure chamber 8 having one end opened. I am configuring. Then, a nozzle plate 12 made of a resin material, a glass material or the like having a nozzle hole 11 corresponding to each pressure chamber 8 is fixed to the front end surface 10 of the actuator portion 9 where each pressure chamber 8 is opened by an adhesive agent. There is.

By the way, in the ink jet recording apparatus, the ejection surface (the front surface 12a of the nozzle plate 12 in which the nozzle holes 11 are arranged) is wetted by the ink mist generated when the ink is ejected or the satellite ink generated when the ink is refilled. Ink adheres or nozzle holes 11
Ink may remain on the ejection surface during recovery processing such as sucking ink from the ink. Therefore, in order to remove such adhered ink, it is necessary to regularly clean the front surface of the nozzle plate 12 during drawing.

For this reason, various cleaning mechanisms have been proposed, and a wiping method such as wiping the nozzle plate 12 with a brush, a porous material, an elastic material or the like has been implemented. Generally, as shown in FIG. 8, the wiping member 1 is arranged in a direction parallel or perpendicular to the arrangement direction of the nozzle holes 11.
3 is sliding. When performing such a wiping method, the wiping property (cleaning property) of the residual ink on the front surface 12a of the nozzle plate 12 is important, and the peeling resistance of the nozzle plate 12 when the wiping material 13 is in contact is also important. is there. However, when a wiping test is performed, for example, when perfluororubber is used as the wiping member 13 and wiping is performed 1000 reciprocations in the arrangement direction of the nozzle holes 11, the wiping member 13 starts to contact the edge portion 12b of the nozzle plate 12. Peeling occurred.

Countermeasures against peeling of the nozzle plate 12 are described in Japanese Patent Application Laid-Open No. 02-187362. In this Japanese Patent Laid-Open No. 02-187362, as shown in FIG.
Front surface 12 of nozzle plate 12 excluding the peripheral portion of nozzle hole 11
By providing the covering member 14 that covers a and the edge portion of the outer side surface of the actuator portion 9 adjacent thereto, the nozzle plate 12 is prevented from being displaced or separated.

[0007]

However, when the covering member 14 is provided on the front surface of the nozzle plate 12 as described above, a step is formed between the nozzle plate 12 and the covering member 14, so that dust and dirt attached There is a problem that not only the residual ink cannot be completely removed, but also wet ink accumulates on this step portion and solidifies.

The present invention solves the above problems, and an object thereof is to remove dust and ink adhering to a nozzle plate by wiping without causing the nozzle plate to peel off.

[0009]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention folds the peripheral edge of a nozzle plate and affixes it to the upper and lower or left and right outer surfaces of an actuator portion, so that ink adhered to the ejection surface and This is to prevent or reduce the peeling of the nozzle plate when wiping dust and the like.

That is, according to the first aspect of the present invention, each pressure chamber has a nozzle plate in which a nozzle hole corresponding to each pressure chamber is formed in an actuator portion in which pressure chambers having one end opened are formed in parallel. In a piezoelectric type inkjet head arranged and fixed so as to cover the open end face, a bent portion is formed on the nozzle plate to cover an outer side surface in a direction intersecting with the open end face of the actuator section. Since there is no step on the surface, the adhered ink, dust, etc. can be effectively removed, and since it is fixed not only at the portion covering the open end surface but also at the bent portion, it does not easily come off during wiping.

According to a second aspect of the present invention, in the ink jet head according to the first aspect, the bent portion of the nozzle plate is an actuator along a direction intersecting a moving direction of a wiping means for wiping the ejection surface of the nozzle plate. Since the edge of the nozzle plate is located on the outer surface of the actuator and does not exist where the wiping member starts to hit, the problem of nozzle plate peeling due to wiping is greatly improved. It

According to a third aspect of the present invention, in the ink jet head according to the first aspect, a chamfered surface is provided between an open end surface of the actuator portion and an outer surface in a direction orthogonal to the open end surface, and the nozzle plate is the actuator. Since the open end surface and the chamfered surface of the part are covered, and the bending angle of the nozzle plate is reduced due to the existence of the chamfered surface, the nozzle plate can be easily attached to the actuator part. Also,
Since the wiping member smoothly moves the surface of the nozzle plate from the portion covering the chamfered surface to the portion covering the open end surface, the impact on the nozzle plate is reduced and the problem of peeling is greatly improved. This configuration is sufficient when the wiping member starts to hit the nozzle plate from the portion covering the chamfered surface.

According to a fourth aspect of the present invention, in the ink jet head according to the first aspect, a chamfered surface is provided between an open end surface of the actuator portion and an outer surface in a direction orthogonal to the open end surface, and the nozzle plate is the actuator. By covering the open end surface of the part, the chamfered surface and the outer surface, the bending angle of the nozzle plate is reduced by the presence of the chamfered surface,
The nozzle plate can be easily attached to the actuator section. Moreover, since the wiping member smoothly moves the surface of the nozzle plate from the portion covering the chamfered surface to the portion covering the open end surface, the impact on the nozzle plate is reduced, and the problem of peeling is greatly improved. Since the edge of the nozzle plate is located on the outer surface of the actuator portion, this configuration is sufficient when the wiping member starts to come into contact with the nozzle plate from the outside of the portion covering the chamfered surface.

According to a fifth aspect of the present invention, in the ink jet head according to the first aspect, an R treatment surface is provided between the open end surface of the actuator portion and an outer surface in a direction orthogonal to the open end surface, and the nozzle plate is the above-mentioned. Since the open end surface of the actuator part and the R-processed surface are covered, the bending angle of the nozzle plate is reduced due to the existence of the R-processed surface, so that the nozzle plate can be easily attached to the actuator part. Also,
Since the wiping member smoothly moves the surface of the nozzle plate from the portion covering the R-treated surface to the portion covering the open end surface, the impact on the nozzle plate is reduced, and the problem of peeling is greatly improved. This configuration is sufficient when the wiping member starts to hit the nozzle plate from the portion covering the R processing surface.

According to a sixth aspect of the present invention, in the ink jet head according to the first aspect, an R treatment surface is provided between the open end face of the actuator portion and an outer face in a direction orthogonal to the open end face, and the nozzle plate is the above-mentioned. The actuator unit covers the open end surface, the R-processed surface, and the outer side surface of the actuator portion, and the presence of the R-processed surface reduces the bending angle of the nozzle plate.
The nozzle plate can be easily attached to the actuator section. Further, since the wiping member smoothly moves the surface of the nozzle plate from the portion covering the R-treated surface to the portion covering the open end face, the impact on the nozzle plate is reduced, and the problem of peeling is greatly improved. Since this structure has the edge of the nozzle plate located on the outer surface of the actuator portion, it is sufficient when the wiping member starts to come into contact with the nozzle plate from outside the portion covering the R processing surface.

According to a seventh aspect of the present invention, in the ink jet head according to any one of the first to sixth aspects, the nozzle plate is made of polyimide resin, and the polyimide resin is easy to bend. The nozzle plate can be attached while being bent along the actuator portion, and the adhesion of the nozzle plate to the actuator portion can be secured. Polyimide resin is also a material that can be drilled with extremely high precision by laser processing.

According to an eighth aspect of the present invention, in the ink jet head according to any one of the first to sixth aspects, the surface of the nozzle plate is subjected to a liquid repellent treatment to prevent ink droplets from adhering. It can be prevented.

According to a ninth aspect of the present invention, a nozzle plate having nozzle holes corresponding to each pressure chamber is formed in an actuator portion in which pressure chambers having one end opened are formed in parallel, and an open end surface where each pressure chamber is opened. When manufacturing a piezoelectric inkjet head by arranging and fixing so as to cover the nozzle plate, the nozzle plate made of a resin material with a bending margin formed on the peripheral portion is aligned with the actuator portion to which an adhesive is applied in advance. By arranging and pressing, the bending margin is attached while being along the outer side surface in the direction intersecting the open end surface of the actuator portion.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION A piezoelectric ink jet head according to an embodiment of the present invention will be described below with reference to the drawings. (Embodiment 1) FIG. 1 shows the structure of a piezoelectric ink jet head according to Embodiment 1 of the present invention. The ink jet head according to the first embodiment has substantially the same configuration as the conventional one described with reference to FIG. 5, and therefore the description will be given also with reference to FIG.

As shown in FIG. 1 (a), the ink jet head has a front end face 10 of an actuator portion 9 made of a piezoelectric ceramic in which pressure chambers 8 having one open end are formed in parallel.
A nozzle plate 12 having nozzle holes 11 corresponding to each pressure chamber 8 is arranged and fixed so as to cover the opening 8 a of the pressure chamber 8.

However, the nozzle plate 12 has a cylindrical shape with a bottom,
The front end surface 10 of the actuator portion 9 having a substantially rectangular parallelepiped shape
And two pairs of outer surfaces 9c and 9d adjacent to the front end surface 10.
Covers the periphery of the.

A method of manufacturing this ink jet head will be described. The nozzle plate 12 is made of a plate material such as a polyimide film having a thickness of 50 μm, and the nozzle hole 5 and the outer shape are processed by an excimer laser, so that the front end face 10 of the actuator portion 9 is processed as shown in FIG. 4 adjacent to the front end face 10 around the ejection region 12a ′ corresponding to
Adhesive regions 12c corresponding to the peripheral portions of the outer side surfaces 9c, 9d,
12d is formed integrally.

When assembled, the viscosity is 3000.
A porous material is impregnated with an adhesive material such as a cps two-component epoxy adhesive agent, and an arbitrary amount is transferred to the front end surface 10 of the actuator portion 9.

The discharge area 12a 'of the nozzle plate 12 is formed on the front end surface 10 of the actuator portion 9 by using a dedicated nozzle attaching jig having a fine position adjusting mechanism, and the nozzle hole 11 and the pressure chamber 8 are opened. 8a Temporary alignment while aligning each other. Then, while confirming that there is no deviation, a pressure of, for example, 2 MPa is applied, and the pressure is 60 at 100 ° C.
The adhesive is heat-cured by leaving it for a minute.

After that, the side surface jig is used to bend the adhesive regions 12c and 12d of the nozzle plate 12 and to attach them to the outer side surfaces 9c and 9d of the actuator portion 9. The adhesive and heat curing conditions at this time are the same as above.

The ink-jet head manufactured in this manner has no step like the conventional ink-jet head in which the covering member is arranged on the ejection surface (the front surface of the nozzle plate 12), so that the wiping can be effectively performed and the ink And dust can be removed. Further, since the nozzle plate 12 is made of polyimide, it has high adhesion to the actuator portion 9 and is not only attached to the front end face 10 of the actuator portion 9,
Since it is also fixed to the outer side surfaces 9c and 9d, it does not easily come off during wiping.

In order to evaluate the adhesiveness between the nozzle plate 12 and the actuator section 9, a wiping material made of perfluororubber is arranged in the direction of arrangement of the nozzle holes 11 (in the figure) in the same manner as described above with reference to FIG. , Left and right) 10 round trips
The nozzle plate 12 was rubbed 00 times and the state of the nozzle plate 12 was observed. No peeling was observed on the nozzle plate 12.

If a liquid-repellent layer such as a fluorine-containing system is formed on the surface of the nozzle plate 12, ink adhesion can be prevented in advance.
Alternatively, it can be reduced. The liquid-repellent layer is, for example, 4
The fluorinated ethylene-6-fluorinated propylene copolymer is applied by using a spin coater, a bar coater or the like, and then heat-treated to form the film. When a spin coater is used, it is possible to form a liquid repellent layer having a thickness of about 2 μm after heating by rotating the spin coater at 2000 rpm for 15 seconds. (Second Embodiment) FIG. 2 shows the structure of a piezoelectric ink jet head according to a second embodiment of the present invention.

This ink jet head is the first embodiment.
2 is different from that of FIG. 1 in that the nozzle plate 12 is U-shaped, and has a substantially rectangular parallelepiped shape, and a front end surface 10 of the actuator portion 9.
This is a point that covers the peripheral portions of the pair of outer side surfaces 9c adjacent to the front end surface 10. The outer side surface 9c is an outer side surface in a direction intersecting the moving direction of the wiping means.

As shown in FIG. 2 (b), the nozzle plate 12 before assembly has a discharge area 12a 'corresponding to the front end surface 10 of the actuator portion 9 and an adhesive area 12c corresponding to the peripheral portion of the outer surface 9c. Are integrally formed. At the time of assembly, the nozzle plate 12 is attached to the actuator unit 9 as in the first embodiment.

In order to evaluate the adhesiveness between the nozzle plate 12 and the actuator section 9 of the ink jet head manufactured in this way, the same procedure as in the first embodiment is carried out.
When the wiping material made of perfluororubber was rubbed 1000 times back and forth and the state of the nozzle plate 12 at that time was observed, no peeling was observed on the nozzle plate 12. (Third Embodiment) FIG. 3 shows the structure of a piezoelectric ink jet head according to a third embodiment of the present invention.

This ink jet head is the first embodiment.
3 is different from that of FIG. 1 in that the front end surface 10 of the actuator portion 9 having a substantially rectangular parallelepiped shape and the outer surface 9c in a direction orthogonal to the front end surface 10
A chamfered surface (an inclined surface in a direction intersecting with both the front end surface 10 and the outer surface 9c) 9e is provided between the nozzle plate 12 and the front end surface 10 of the actuator portion 9 by polishing or cutting. This is a point that covers the chamfered surface 9e and the peripheral edge of the outer surface 9c.

According to this, since the bending angle of the nozzle plate 12 is reduced by the presence of the chamfered surface 9e, the nozzle plate 12 can be easily attached to the actuator portion 9. Further, since the wiping member smoothly moves the surface of the nozzle plate 12 from the portion covering the chamfered surface 9e to the portion covering the front end face 10, the impact on the nozzle plate 12 is reduced and the nozzle plate 12 is not peeled off. The problem is greatly improved.
This configuration is effective when the tip portion of the wiping member starts to contact the nozzle plate 12 from the outside of the portion that covers the chamfered surface 9e.

When the tip of the wiping member is constructed so as to start contacting with the chamfered surface 9e, the nozzle plate 12 is attached only to the front end surface 10 of the actuator portion 9 and the chamfered surface 9e as shown in FIG. You may provide so that it may cover.

In the third embodiment, the chamfering process is performed on both sides of the front end face 10 of the actuator portion 9. However, the chamfering process is performed on all four sides of the front end face 10 of the actuator portion 9, and the chamfering process is performed. You may make it arrange | position the bottomed cylindrical nozzle plate 12 like the form 1. (Fourth Embodiment) FIG. 5 shows the structure of a piezoelectric ink jet head according to a fourth embodiment of the present invention.

This ink jet head is the first embodiment.
3 is different from that of FIG. 1 in that the front end surface 10 of the actuator portion 9 having a substantially rectangular parallelepiped shape and the outer surface 9c in a direction orthogonal to the front end surface 10
R processing surface 9f is provided by R processing such as polishing and cutting between the nozzle and the nozzle plate 12, and the nozzle plate 12 covers the front end surface 10 of the actuator portion 9, the R processing surface 9f, and the peripheral portion of the outer surface 9c. That is the point.

According to this, since the bending angle of the nozzle plate 12 is reduced due to the existence of the R processed surface 9f, the nozzle plate 12 can be easily attached to the actuator portion 9. Further, the wiping member is provided on the surface of the nozzle plate 12,
Since it moves smoothly from the portion covering the processing surface 9f to the portion covering the front end surface 10, the impact on the nozzle plate 12 is reduced, and the problem of peeling is greatly improved.
This configuration is effective when the tip portion of the wiping member starts to come into contact with the nozzle plate 12 from the outside of the portion covering the R processing surface 9f.

When the tip of the wiping member is configured to start contact with the R processing surface 9f, the nozzle plate 12 is connected to the front end surface 10 of the actuator portion 9 and the R processing surface as shown in FIG. You may provide so that only 9f may be covered.

In the fourth embodiment, the R treatment is applied to both sides of the front end face 10 of the actuator portion 9, but the R treatment is applied to all four sides of the front end face 10 of the actuator portion 9, You may make it arrange | position the bottomed cylindrical nozzle plate 12 like Embodiment 1.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing a configuration of a piezoelectric inkjet head according to a first embodiment of the present invention and a shape of a nozzle plate, which is a component thereof, before being assembled.

FIG. 2 is an explanatory diagram showing a configuration of a piezoelectric inkjet head according to a second embodiment of the present invention and a shape of a nozzle plate that is a component thereof before assembly.

FIG. 3 is a plan view showing the configuration of a piezoelectric inkjet head according to a third embodiment of the present invention.

FIG. 4 is a plan view of a piezoelectric inkjet head having a different arrangement of nozzle plates from the inkjet head of FIG.

FIG. 5 is a plan view showing the configuration of a piezoelectric inkjet head according to a fourth embodiment of the present invention.

FIG. 6 is a plan view of a piezoelectric ink jet head in which the arrangement of the nozzle plate and the ink jet head of FIG. 5 is different.

FIG. 7 is an explanatory diagram showing a configuration of a conventional piezoelectric inkjet head.

FIG. 8 is an explanatory diagram showing a state in which the inkjet head of FIG. 7 is wiped.

FIG. 9 is an explanatory diagram showing the configuration of another conventional piezoelectric inkjet head.

[Explanation of symbols]

8 pressure chambers 9 Actuator part 9c, 9d outer surface 9e Chamfer 9f R treated surface 10 Front end face (Open end face) 11 Nozzle hole 12 nozzle plate 12c, 12d Bonding area (folded part)

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Hirofumi Sugimoto             1 Juden Matsushita, 1-8 Koshinmachi, Takamatsu City, Kagawa Prefecture             Child Industry Co., Ltd. (72) Inventor Takayoshi Oga             1 Juden Matsushita, 1-8 Koshinmachi, Takamatsu City, Kagawa Prefecture             Child Industry Co., Ltd. (72) Inventor Naoyuki Seo             1 Juden Matsushita, 1-8 Koshinmachi, Takamatsu City, Kagawa Prefecture             Child Industry Co., Ltd. F-term (reference) 2C057 AF65 AF93 AG12 AP13 AP25                       AP57 AP60 AP72 BA03 BA14

Claims (9)

[Claims] 1. A nozzle plate having nozzle holes corresponding to the pressure chambers is arranged and fixed to an actuator portion in which pressure chambers each having one end opened are arranged in parallel so as to cover the open end face of each pressure chamber. In the piezoelectric type inkjet head described above, the nozzle plate has a bent portion formed along an outer surface in a direction intersecting with the open end surface of the actuator portion. 2. The ink jet head according to claim 1, wherein the bent portion of the nozzle plate covers an outer surface of the actuator portion along a direction intersecting a moving direction of a wiping unit that wipes a discharge surface of the nozzle plate. 3. The chamfered surface is provided between an open end surface of the actuator portion and an outer surface in a direction orthogonal to the open end surface, and the nozzle plate covers the open end surface and the chamfered surface of the actuator portion. Inkjet head. 4. A chamfered surface is provided between an open end surface of the actuator portion and an outer surface in a direction orthogonal to the open end surface, and the nozzle plate covers the open end surface, the chamfered surface and the outer surface of the actuator portion. 1. The inkjet head according to 1. 5. The R processing surface is provided between the open end surface of the actuator portion and an outer surface in a direction orthogonal to the open end surface, and the nozzle plate covers the open end surface and the R processing surface of the actuator portion. The described inkjet head. 6. An R processing surface is provided between an open end surface of the actuator portion and an outer surface in a direction orthogonal to the open end surface, and the nozzle plate covers the open end surface, the R processing surface and the outer surface of the actuator portion. The inkjet head according to claim 1. 7. The ink jet head according to claim 1, wherein the nozzle plate is made of a polyimide resin. 8. The ink jet head according to claim 1, wherein the surface of the nozzle plate is subjected to a liquid repellent treatment. 9. A nozzle plate having nozzle holes corresponding to each pressure chamber is arranged and fixed to an actuator portion in which pressure chambers having one end opened are arranged in parallel so as to cover the open end face of each pressure chamber. When manufacturing a piezoelectric ink jet head, the nozzle plate made of a resin material with a bending margin formed on the peripheral portion is aligned with the actuator portion coated with an adhesive in advance and pressed. A method for manufacturing an inkjet head, in which the folding margin is applied along an outer surface in a direction intersecting the open end surface of the actuator portion.