JPH05116329A - Manufacture of ink jet printer head - Google Patents

Abstract

PURPOSE:To contrive to improve the productivity of an ink jet printer head by making a pressure-producing means composed of piezoelectric ceramic homogeneous and mass-producible through forming the pressure-producing means by injection molding of the piezoelectric ceramic. CONSTITUTION:In this ink jet et printer head 1, a body plate 2 with projections and recesses formed on the under surface and a flat body plate 3 are joined integrally and an orifice plate 6 with orifices 5 formed in positions communicating with pressure chambers 4 composed of the recesses of the body plate 2 is attached to the fronts of the body plates 2, 3. In this printer head 1, further, a piezoelectric ceramic 7 being a pressure-producing means attached onto the body plate 3 is formed into a comblike shape by injection molding, and individual electrodes 9 and common electrodes 10 are formed on respective top and under surfaces of the divided actuators 8 of the ceramic and located in the pressure chambers 4 of the body plate 2. Thus, the piezoelectric ceramic 7 of the pressure-producing means is formed by injection molding so that a homogeneous mass production is possible and productivity is satisfactory in the head 1.

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 on-demand type ink jet printer head.

[0002]

2. Description of the Related Art At present, as a printer capable of quiet and high-density printing, an ink jet printer or the like, which ejects ink droplets from an orifice to fix it on a printing paper, has been put into practical use.

For example, an on-demand type ink jet printer head has a structure in which a pressure generating means at least the surface of which is displaceable is provided in a pressure chamber communicating with each of the orifices arranged in an array. Then, in such an inkjet printer head, the pressure generating means is vibrated by the drive power corresponding to the print image, and the ink in the pressure chamber is ejected as an ink droplet from the orifice.

At present, it has been proposed to use piezoelectric ceramics as a pressure generating means for the above-mentioned ink jet printer head. Since this piezoelectric ceramic has good corrosion resistance and strength, it can be used as a structural material for forming a pressure chamber or the like, and it is desired to improve its productivity and increase its density. As such an ink jet printer head, one in which a strip-shaped or cylindrical piezoelectric ceramic is provided for each pressure chamber has been put into practical use, and a plate-shaped piezoelectric ceramic is secondarily processed or green. It has been proposed to form the pressure generating means by processing the sheet.

For example, in the ink jet printer head disclosed in Japanese Patent Laid-Open No. 55-17575, two flat plate-shaped piezoelectric ceramics are bonded so that concave grooves formed by selective etching on each surface face each other. As a result, the piezoelectric ceramic serves as both the structural material and the pressure generating means using the void formed by the communicating groove as a pressure chamber. Similarly, in the inkjet printer head disclosed in JP-A-62-56150, JP-A-63-129173, and JP-A-2-150355, concave grooves are formed on one side or both sides by cutting such as dicing. It has a structure in which a flat plate-shaped cover plate is joined to the formed flat plate-shaped piezoelectric ceramic, and the piezoelectric ceramic also serves as a structural material and a pressure generating means by using the void in the concave groove as a pressure chamber. Is becoming

Further, in the ink jet printer head disclosed in Japanese Patent Laid-Open No. 2-92644, a flat piezoelectric ceramic is formed into a comb tooth shape by etching by photolithography, and the divided tip portion is pressure generating means. It is designed to be used as. Furthermore, JP-A-63-173
In the inkjet printer head disclosed in Japanese Patent Laid-Open No. 64, two flat plate-shaped piezoelectric ceramics formed in a comb shape by cutting such as dicing are joined via a spacer,
The piezoelectric ceramic serves as a structural material and a pressure generating means by using a space formed by a spacer between the divided tip portions as a pressure chamber. In addition, JP-A-63-25275
In the inkjet printer head disclosed in Japanese Patent No. 0, the two flat plate-shaped piezoelectric ceramics formed into a comb-tooth shape by cutting with a diamond cutter or laser processing are joined to each other and covered with two flat plate-shaped cover plates. In addition, the piezoelectric ceramic serves as a structural material and a pressure generating means by using a space formed between the divided tip portions of the piezoelectric ceramic and the cover plate as a pressure chamber.

Further, in the ink jet printer head disclosed in Japanese Patent Laid-Open No. 63-149459, a plurality of green sheets having through-grooves of a predetermined shape formed by press working or laser working are sequentially laminated and fired. The piezoelectric ceramic serves as a structural material and a pressure generating means by using the void in the piezoelectric ceramic as a pressure chamber or an orifice.

In the ink jet printer head disclosed in Japanese Unexamined Patent Publication (Kokai) No. 62-101453, a hole pattern is previously formed by using a photo-etched photosensitive resin, and a through groove having a predetermined shape is formed by press working or the like. After stacking multiple green sheets through the hole pattern, the hole pattern of the photosensitive resin in the piezoelectric ceramic fired after pressurizing this is removed with a binder, and this void is used as a pressure chamber. The piezoelectric ceramic serves as both the structural material and the pressure generating means.

[0009]

In the manufacturing method disclosed in the above publication, the pressure generating means and the structural material of the ink jet printer head are formed of piezoelectric ceramic to improve the strength and corrosion resistance thereof and simplify the structure. There is.

Here, Japanese Patent Application Laid-Open No. 55-17575 and Japanese Patent Application Laid-Open No.
Japanese Patent No. 92644 discloses that piezoelectric ceramics are molded by selective etching. However, in practice, piezoelectric ceramics are difficult to wet-chemically etch, and ion milling method and the like are carried out. However, this impedes the productivity of the device because the processing speed is extremely low.

Further, JP-A-62-56150 and JP-A-63-1
29173, JP-A-2-150355, JP-A-63-17364
The publication discloses that piezoelectric ceramics are formed by cutting such as dicing. However, since the hardness of ceramics is extremely high, this cutting is slow and the productivity of the device is hindered, and the tool life is also shortened. It is not preferable because it will decrease.

Japanese Unexamined Patent Publication (Kokai) No. 63-252750 discloses forming a piezoelectric ceramic by laser processing. However, in order to improve the accuracy of laser processing, the intensity of laser light is reduced. However, the processing speed is reduced and the productivity of the apparatus is hindered.

Further, Japanese Laid-Open Patent Publication No. 63-149459 discloses that a green sheet formed by press working or laser processing is fired to obtain a piezoelectric ceramic having a predetermined shape. It is necessary to reduce the intensity of the laser light to improve the accuracy, which hinders the productivity, and it is difficult to form a three-dimensional shape by press working, and cracks are likely to occur in the processed portion, which is not preferable. ..

In Japanese Patent Laid-Open No. 62-101453, a green sheet formed by pressing or the like is laminated through a hole pattern of a photosensitive resin, and after the firing, the hole pattern is removed to obtain a predetermined pattern. Although it has been disclosed to obtain a piezoelectric ceramic having a shape, this is not preferable because the number of manufacturing steps is increased and the work is complicated, so that the productivity of the device is significantly reduced.

The present invention provides a method of manufacturing an ink jet printer head with good productivity.

[0016]

The invention according to claim 1 is
At least a surface of which a pressure generating means is displaceable is provided in a pressure chamber in which the orifice and the ink supply passage communicate with each other, and the ink supplied from the ink supply passage and held in the pressure chamber is pressurized by the pressure generating means and discharged from the orifice. In the thus configured ink jet printer head, the pressure generating means is formed by injection molding of piezoelectric ceramic.

According to a second aspect of the invention, in the first aspect of the invention, the structural material forming both the pressure generating means and the orifice is formed by injection molding of piezoelectric ceramic.

[0018]

According to the first aspect of the present invention, the pressure generating means made of piezoelectric ceramic can be mass-produced uniformly, which can contribute to the improvement of the productivity of the ink jet printer head.

According to the second aspect of the present invention, the pressure generating means and the structural material forming the orifice are formed at the same time.
Further, it can contribute to the improvement of the productivity of the inkjet printer head.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the invention described in claim 1 will be described with reference to FIGS. First, in this ink jet printer head 1, as illustrated in FIG. 1, a main body plate 2 having a concave and convex bottom surface and a flat plate-like main body plate 3 are integrally joined to each other. An orifice plate 6 having an orifice 5 formed at a position communicating with the pressure chamber 4 is attached to the front surfaces of the body plates 2 and 3. In this inkjet printer head 1, as illustrated in FIG. 2, the piezoelectric ceramic 7 which is the pressure generating means mounted on the main body plate 3 is formed in a comb shape by injection molding, and the division thereof is performed. The driven unit 8 is formed in the pressure chamber 4 of the main body plate 2 with the individual electrodes 9 and the common electrode 10 formed on the upper and lower surfaces thereof.

Here, an example of a method of manufacturing each part of the above-mentioned ink jet printer head 1 will be described in detail below. First, the piezoelectric ceramic 7 is set to PZT (Lead Z
ircoTitanate), TiO ₂ , PbO and ZrO
_The ceramic raw material consisting of ₂ and the characteristic improving agent is mixed and dried, and this is calcined and then kneaded with the organic binder.
Then, a powder, which is a molding material formed by crushing the powder, is injected into a mold having a predetermined shape by an injection molding machine to form a comb-tooth-shaped molded product (green molded body). Therefore, the organic component in this molded product is volatilized in a degreasing furnace, and the piezoelectric ceramic 7 is molded by firing (main sintering).

Therefore, the comb-shaped piezoelectric ceramics 7 as described above are subjected to finishing processing such as polishing as desired, and the divided upper and lower surfaces of the driving portion 8 are formed of metal films with respective electrodes. 9 and 10 are formed. Then, the piezoelectric ceramic 7 is placed in silicon oil of 80 to 120 (° C.) and an electric field of 2 to 5 (kV / mm) is applied between the electrodes 9 and 10 to generate the piezoelectric ceramic 7. The driving unit 8 is polarized in the direction in which the electrodes 9 and 10 face each other. The piezoelectric ceramic 7 as described above can also be implemented by a ternary system in which a complex perovskite oxide is added to the PZT binary system.

The electrodes 9 and 10 made of the metal film as described above can be formed by printing, sputtering, plating or the like. The individual electrode 9 is divided for each drive unit 8, but the common electrode 10 is It has a shape that is integrally communicated at the end.

Further, the main body plates 2 and 3 and the orifice plate 6 of the ink jet printer head 1 are
For example, it is formed of a ceramic such as alumina, and it can be manufactured by injection molding similarly to the piezoelectric ceramic 7 described above.

With this structure, in the ink jet printer head 1, the driving power corresponding to the print image is selectively applied between the electrodes 9 and 10, and the predetermined driving portion 8 of the piezoelectric ceramic 7 is moved vertically. When expanded and contracted, the ink (not shown) in the pressure chamber 4 located on the drive unit 8 is pressurized and ejected from the orifice 5, so that the ejected ink droplet relatively moves in the sub scanning direction. An image is formed by adhering onto a sheet (not shown).

The pressurization of the ink by the expansion and contraction of the piezoelectric ceramic 7 as described above is realized by the abrupt expansion of the drive unit 8 or the abrupt restoration after the gentle contraction. In addition, since the driving portion 8 of the piezoelectric ceramic 7 expands and contracts in the left-right direction as it expands and contracts in the vertical direction, this may adversely affect the pressurization of the ink. Therefore, as a means for solving this, the driving portion 8 of the piezoelectric ceramic 7 is enlarged in the vertical direction as compared with the horizontal direction, and the expansion / contraction amount in the horizontal direction is reduced to an amount that does not pose a practical problem. It is possible to put an elastic body (not shown) such as silicon rubber in the gap between the both side surfaces of each drive unit 8 and the inner side surface of the pressure chamber 4. It is also possible to implement an inkjet printer head (not shown) in which the driving portion 8 of the piezoelectric ceramic 7 having the above-described shape is polarized in the left-right direction and electrodes are formed on both side surfaces thereof.

Here, in the ink jet printer head 1, the piezoelectric ceramic 7 as the pressure generating means is formed by injection molding, so that it is possible to easily realize uniform mass production, and to improve its productivity and shape accuracy. Is very good. Moreover, in the ink jet printer head 1 of the present embodiment, the plates 2, 3 and 6 forming the pressure chamber 4 and the orifice 5 are formed by injection molding of ceramic, so that this is excellent in productivity and shape accuracy. At the same time, it has good strength and corrosion resistance.

Next, a second embodiment of the invention according to claim 1 will be described with reference to FIGS. 3 and 4. First, in the ink jet printer head 11, as illustrated in FIG. 3, a main body plate 12 having an uneven surface on its lower surface and a main body plate 13 made of piezoelectric ceramic having an uneven surface on its upper surface are integrally joined. An orifice plate 16 having an orifice 15 formed at a position communicating with the pressure chamber 14 formed of a concave portion of the main body plate 12 is attached to the front surfaces of the main body plates 12 and 13. The inkjet printer head 11 shown in FIG.
As illustrated in FIG. 2, the driving unit 17 continuously protruding from the upper surface of the body plate 13 has electrodes 18 on both side surfaces.
19 are formed and polarized in the left-right direction, and are respectively located in the pressure chambers 14 of the main body plate 12.

With this structure, in the ink jet printer head 11, the driving power is the electrodes 18, 1.
A predetermined drive portion 17 of the main body plate 13 expands and contracts in the left-right direction by being selectively energized during 9, and image formation is performed in the same manner as in the inkjet printer head 1 described above as the first embodiment.

Here, in this ink jet printer head 11, the ink jet printer head 1 described above is used.
Like the piezoelectric ceramic 7 of No. 1, the main body plate 13 made of piezoelectric ceramic such as PZT is formed by injection molding, and its productivity and shape accuracy are extremely good. Moreover, in the inkjet printer head 11, the main body plate 13 serves both as the pressure generating means for pressurizing the ink and as the structural material forming the pressure chamber 14, so that simplification of the structure and reduction of the number of parts are realized. There is.

The electrodes 18 and 19 as described above can be easily formed by sputtering or vapor deposition by using the driving portion 17 that is inclined and projected from the main body plate 13 as a mask. Incidentally, such a manufacturing method is disclosed in detail in JP-A-2-150355. further,
It is also possible to form a metal film on the entire surface of the main body plate 13 by electroless plating or the like, and partially remove the metal film by polishing or dicing to form the electrodes 18 and 19.

An ink jet printer head (not shown) in which the body plate 13 as described above is vertically polarized and a common electrode is formed on the lower surface of the body plate 13 and individual electrodes are formed on the upper surface of the driving unit 17 is also implemented. It is possible.

Next, a third embodiment of the present invention will be described with reference to FIGS. 5 and 6. First, in the ink jet printer head 20, as illustrated in FIG. 5, the body plates 21 and 22 are joined by two comb-shaped piezoelectric ceramics, and the body plates 21 and 22 joined together are integrated. Is a flat cover plate 23,
It is covered with 24 from the top and bottom. The gap formed by the cover plates 23, 24 and the divided drive portions 25, 26 of the main body plates 21, 22 is a pressure chamber 27, and an orifice 28 communicating with these pressure chambers 27 is formed. An orifice plate 29 in which is formed is attached to the front surfaces of the plates 21 to 24. The inkjet printer head 20 shown in FIG.
2, the body plates 21 and 22 are formed into a comb shape by injection molding of a piezoelectric ceramic and are polarized in opposite directions in the vertical direction.
6, electrodes 30 and 31 are formed on both side surfaces of the electrode 6, respectively.

In the ink jet printer head 20 having such a structure, the driving power is supplied to the electrodes 30, 3.
When electricity is applied between the two driving portions 25 and 26 of the two body plates 21 and 22 which are polarized in opposite directions, the joined central portions are deformed in the left-right direction. Ink (not shown) in the positioned pressure chamber 27 is pressurized and ejected from the orifice 28. In the ink jet printer head 20, the driving units 25 and 26 located between the two pressure chambers 27 are deformed to the left and right to pressurize the ink as described above. Drops cannot be ejected. Therefore, in the inkjet printer head 20, the driving units 25 and 26 are time-divisionally driven with respect to the pressure chambers 27 so that the ink droplets ejected from the orifices 28 which are alternately displaced in the sub-scanning direction are arranged in a line on the printing paper. It is designed to line up.

Here, the main body plate 21 made of piezoelectric ceramic of the ink jet printer head 20,
22 is formed by injection molding similarly to the piezoelectric ceramic 7 of the inkjet printer head 1 described above,
Its productivity and shape accuracy are extremely good. Moreover, in the inkjet printer head 20, as in the inkjet printer head 11 described above, the main body plates 21 and 22 also function as pressure generating means for pressurizing the ink and a structural material forming the pressure chamber 27. Has been realized and the number of parts has been reduced.

The body plates 21, 2 as described above
When 2 is polarized in the vertical direction, for example, the drive unit 25,
Electrodes (not shown) are formed on the upper and lower surfaces of 26 and polarized,
After that, the electrodes on the upper and lower surfaces of the driving portions 25 and 26 are removed to form the electrodes 30 and 31 on both side surfaces.
It is possible to carry out a polarization treatment by pressing electrodes made of a metal plate on the upper and lower surfaces of 26 by pressure. Further, such electrodes 30 and 31 can be formed by partially removing a metal film formed by electroless plating or the like on the entire surface of each body plate 21 or 22 by polishing or dicing. Can also be formed after joining the respective body plates 21, 22.

Next, a fourth embodiment of the invention according to claim 1 will be described with reference to FIGS. 7 and 8. In this inkjet printer head 32, as illustrated in FIG.
A flat plate-shaped cover plate 3 is provided on the upper and lower surfaces of a main body plate 33 made of a piezoelectric ceramic having upper and lower surfaces having irregularities.
4, 35 are integrally joined, and the main body plate 3
An orifice plate 38 having an orifice 37 formed at a position communicating with the pressure chamber 36 formed of the concave portion 3 is attached to the front surfaces of the plates 33 to 35. In the ink jet printer head 32, as illustrated in FIG. 8, the main body plate 33 is vertically polarized, and the drive unit 3 is continuously provided on the upper and lower surfaces thereof.
Electrodes 41 and 42 are formed on both side surfaces of the tip portions of 9 and 40, respectively.

In the ink jet printer head 32 having such a structure, driving power is supplied to the electrodes 41 and 4.
When electricity is applied between the two, the ends of the drive parts 39, 40 of the main body plate 33 made of piezoelectric ceramic are deformed in the left-right direction, so that the ink inside the pressure chamber 36 located in the direction of deformation thereof
(Not shown) is pressurized and discharged from the orifice 37. Since the ink jet printer head 32 cannot eject ink droplets simultaneously from the two adjacent orifices 37, the driving units 39 and 4 are the same as the ink jet printer head 20 described above.
0 is time-divisionally driven to align the ink droplets in a line on the printing paper.

Here, in the ink jet printer head 32, since the main body plate 33 which is also made of piezoelectric ceramic is formed by injection molding, the productivity and the shape accuracy thereof are extremely good, and the main body plate 33.
Since the pressure generating means for pressurizing the ink is also used as the structural material forming the pressure chamber 36, the structure is simplified and the number of parts is reduced.

In the ink jet printer head 32, the electrodes 41 and 42 are formed only on the tip portions of the driving portions 39 and 40, which are adjusted by adjusting the inclination angle of the main body plate 33. By using as a mask, it can be formed by sputtering or vapor deposition.

When the main body plate 33 made of piezoelectric ceramic as described above is vertically polarized, electrodes are formed on the upper and lower surfaces and removed after the polarization treatment, or the upper and lower surfaces are made of a metal plate. It is possible to perform the polarization treatment by pressing the electrodes. Further, the electrodes 41 and 42 as described above can be easily formed by sputtering or vapor deposition by using the driving portions 39 and 40 that are inclined and projected from the main body plate 33 as a mask.

In the ink jet printer head 32, the driving portions 39 and 40 located on both sides have the electrodes 41 and 42 formed on only one of the both sides.
This cannot be driven and ink droplets cannot be ejected from the orifices 37 on both sides, but this is due to the main plate 3
This is solved by forming electrodes 41 and 42 at predetermined positions on both side surfaces of No. 3.

Next, a fifth embodiment of the invention according to claim 1 will be described with reference to FIGS. 9 and 10. In this ink jet printer head 43, as illustrated in FIG. 9, a main body plate 44 made of a piezoelectric ceramic having concave and convex portions on its lower surface and a main body plate 45 having concave and convex portions on its upper surface are integrally joined. An orifice plate 48, in which an orifice 47 is formed, is attached to the front surface of the plates 44, 45 at a position communicating with the pressure chamber 46 formed of the recess of the main body plate 45. And
In this inkjet printer head 43, for example,
The body plate 44 is vertically polarized, and as illustrated in FIG. 10, electrodes 50 and 51 are formed on an end surface and a back surface of a driving unit 49 that is provided in a row on the lower surface thereof.

In this structure, in the ink jet printer head 43, driving power is supplied to the electrodes 50 and 5.
When the voltage is applied between 1 and 2, the drive portion 49 of the main body plate 44 made of a piezoelectric ceramic expands and contracts in the vertical direction, so that the ink (not shown) in the pressure chamber 46 located in the deformation direction is pressurized and discharged from the orifice 47. Is ejected.

Here, in the ink jet printer head 43, since the main body plate 44 which is also made of piezoelectric ceramic is formed by injection molding, the productivity and the shape accuracy are extremely good, and the main body plate 44 is used.
Since the pressure generating means for pressurizing the ink is also used as the structural material forming the pressure chamber 46, the structure is simplified and the number of parts is reduced.

In this ink jet printer head 43, since the electrode 51 formed on the back surface of the drive unit 49 is located on the flat upper surface of the main body plate 44, it is an electrode formed by plating, printing, sputtering or the like. It is easily formed by patterning the film by etching or the like. In addition, the electrode 50 formed on the end surface of the driving unit 49
In addition to forming by the method described above, it is also possible to form the electrode film with the recesses other than the electrode 50 masked with a filler or the like and then remove the filler.

Furthermore, in the ink jet printer head 43 of this embodiment, the pressure chamber 46 is formed by arranging the concave portion of the main body plate 45 on the end surface of the drive portion 49 of the main body plate 44 in a separated state. For example, it is also possible to join the end surface of the drive unit 49 of the main body plate 44 to the bottom surface of the recess of the main body plate 45 to form pressure chambers on both sides of the drive unit 49. In this case, the drive unit 49
By applying pressure and heat to the main body plate 45 having the electrode 51 formed on the bottom surface of the concave portion, the main body plate 44 having a conductive adhesive applied or an electrically conductive film formed on the end surface of It is possible to join the electrodes 51.

Next, a sixth embodiment of the present invention will be described with reference to FIGS. 11 and 12. In this inkjet printer head 52, as illustrated in FIG. 11, a main body plate 53 having an uneven surface on its upper surface, a thin vibrating plate 54 having elasticity, and a flat piezoelectric plate having an uneven surface on its lower surface. Ceramic 55 and recess 5 on the bottom surface
The cover plate 57 on which 6 is formed is sequentially joined. Here, in the inkjet printer head 52, the orifice 58 and the pressure chamber 59 are formed by sealing the concave portion of the main body plate 53 with the vibration plate 54.
And the drive portion 60 of the piezoelectric ceramic 55 is in contact with the vibration plate 54 at a position above the pressure chamber 59. In the inkjet printer head 52, for example, the piezoelectric ceramic 55 is vertically polarized, and as illustrated in FIG. 12, the end surface and the back surface of the driving unit 60 projecting in a line on the lower surface thereof. Electrodes 61 and 62 are formed on the and.

In the ink jet printer head 52 having such a structure, the driving power is supplied to the electrodes 61 and 6.
When applied between the two, the driving portion 60 of the piezoelectric ceramic 55 expands and contracts in the vertical direction to displace a predetermined position of the vibration plate 54 in the vertical direction, so that the ink in the predetermined pressure chamber 59 located below the vibration plate 54 is displaced. (Not shown) is pressurized and discharged from the orifice 58.

In this ink jet printer head 52, since the piezoelectric ceramic 55 is also formed by injection molding, the productivity and the shape accuracy are extremely good, and the piezoelectric ceramic 55 presses the ink. Since the pressure generating means also serves as the structural material forming the pressure chamber 59, simplification of the structure and reduction of the number of parts are realized.

Next, a seventh embodiment of the invention according to claim 1 will be described with reference to FIG. In this inkjet printer head 63, a main body plate 64 having an uneven surface formed thereon, a thin vibrating plate 65 having elasticity,
A flat plate-shaped piezoelectric ceramic 66 having irregularities formed on its lower surface.
And a cover plate 68 having a recess 67 formed on the lower surface thereof are sequentially joined. Here, in this inkjet printer head 63, the main body plate 6
An orifice 69 and a pressure chamber 70 are formed by sealing the concave portion of No. 4 with the vibration plate 65.
The piezoelectric ceramic 66 is attached to the vibrating plate 65 at the upper position.
The drive unit 71 of is in contact.

Here, in the ink jet printer head 63, each of the pressure chamber 70 of the main body plate 64 and the driving portion 71 of the piezoelectric ceramic 66 is formed in a staggered arrangement in two rows in front and rear. The orifices 69 are formed with an array density that is twice the array density in one row of the drive units 71 and the drive units 71. In the inkjet printer head 63, for example, the piezoelectric ceramic 66 is vertically polarized, and the driving unit 7 is provided.
Electrodes (not shown) are formed on the end surface and the back surface of the electrode 1.

With this structure, in the ink jet printer head 63, when drive power is applied between the electrodes, the drive portion 71 of the piezoelectric ceramic 66 expands and contracts in the vertical direction to displace a predetermined position of the diaphragm 65 in the vertical direction. Therefore, the pressure chamber 70 facing the displacement position of the vibrating plate 65
The ink (not shown) inside is pressurized and ejected from the orifice 69.

In this ink jet printer head 63, since the piezoelectric ceramic 66 is formed by injection molding as well, its productivity and shape accuracy are extremely good, and this piezoelectric ceramic 66 presses the ink. Since the pressure generating means also serves as the structural material forming the pressure chamber 70, simplification of the structure and reduction of the number of parts are realized.

In the ink jet printer head 63, as described above, the pressure chambers 70 and the driving portions 71 are formed in a zigzag arrangement in front and rear rows, and the orifice 6 is formed.
Since the arrangement density of 9 is doubled, it is possible to contribute to the improvement of printing density with a simple structure.

Next, a first embodiment of the invention according to claim 2 will be described with reference to FIGS. 14 and 15. First, in this inkjet printer head 72, as shown in FIG. 14, a flexible plate-like cover plate 74 is integrally formed on a main body plate 73 which is a structural material made of piezoelectric ceramic having an uneven surface. It has a joined structure. Here, this inkjet printer head 7
In FIG. 2, the main body plate 73 is continuously provided with a rectangular frame-shaped drive portion 75 having a concave portion formed on the front surface, and the upper opening of the drive portion 75 is sealed by the cover plate 74 to form an internal space. A pressure chamber 76 is formed and an orifice 77 is formed in the recess. In the inkjet printer head 72, for example, the main body plate 73 is vertically polarized, and as illustrated in FIG. 15, the electrodes 78 and 79 are provided on the end faces and the back faces of both sides of the drive unit 75. Has been formed.

In the ink jet printer head 72 having such a structure, the driving power is supplied to the electrodes 78, 7.
When applied between 9 and 9, the driving portion 75 of the main body plate 73 made of piezoelectric ceramic expands and contracts in the vertical direction to displace a predetermined position of the cover plate 74 in the vertical direction. Ink in
(Not shown) is pressurized and discharged from the orifice 77.

In this ink jet printer head 72, since the main body plate 73 which is also made of piezoelectric ceramic is formed by injection molding, its productivity and shape accuracy are extremely good, and this main body plate 73 is used.
Is a structural material that forms both the pressure generating means for pressurizing the ink and the orifice 77, so that the structure is simplified and the number of parts is reduced.

In the ink jet printer head 72, a plurality of drive parts 7 connected to the main body plate 73 are connected.
Although it has been illustrated that the upper opening of No. 5 is sealed with one flexible cover plate 74 to improve the productivity, for example, such cover plate 74 is cut for each drive unit 75 to prevent crosstalk precisely. It is also possible to do so.

Next, a second embodiment of the invention according to claim 2 will be described with reference to FIGS. First, in this inkjet printer head 80, as illustrated in FIG. 16, on a main body plate 81, which is a structural material made of piezoelectric ceramic, in which rectangular recesses are continuously provided on the upper surface,
It has a structure in which a flexible flat plate-shaped cover plate 82 is integrally joined. Here, in the inkjet printer head 80, a drive unit 83 is continuously provided by a partition between rectangular recesses formed on the upper surface of the main body plate 81, and an upper opening of the drive unit 83 is provided in the cover plate 8.
The pressure chamber 84 is formed in the internal space by sealing the chamber 2 with the pressure chamber 84. Then, the inkjet printer head 80
In the above, an orifice 85 communicating with the pressure chamber 84 is formed on the front surface of the main body plate 81, and, as illustrated in FIG. 17, on both side surfaces of the upper portion of the drive portion 83 of the main body plate 81 that is vertically polarized. Electrodes 86 and 87 are formed. In addition, this inkjet printer head 80
Then, as illustrated in FIG. 18, the cover plate 8
A concave portion is formed on the lower surface of No. 2, and the concave portion communicates with the pressure chamber 84 of the main body plate 81 to form an ink supply passage 88.

In the ink jet printer head 80, since the facing direction of the electrodes 86 and 87 and the polarization direction of the body plate 81 intersect, the body plate 81 is polarized before the cover plate 82 is joined. I need to do it. Therefore, if the cover plate 82 is joined to the main body plate 81 by thermocompression bonding or the like, there is a concern that the polarization characteristics of the drive portion 83 may deteriorate.
It is desirable that the bonding of Nos. 1 and 82 is performed with an organic adhesive or the like.

In the ink jet printer head 80 having such a structure, the driving power is supplied to the electrodes 86, 8.
When applied between 7 and 7, the drive portion 83 of the main body plate 81 made of piezoelectric ceramic expands and contracts in the vertical direction to displace a predetermined position of the cover plate 82 in the vertical direction. Ink in
(Not shown) is pressurized and discharged from the orifice 85.

In this ink jet printer head 80, since the main body plate 81 which is also made of piezoelectric ceramic is formed by injection molding, the productivity and the shape accuracy are extremely good, and the main body plate 81 is used.
Is a structural material that forms both the pressure generating means for pressurizing the ink and the orifice 85, so that the structure is simplified and the number of parts is reduced.

[0064]

According to the first aspect of the present invention, at least the surface of the pressure generating means is provided in the pressure chamber where the orifice and the ink supply passage communicate with each other, and the pressure generating means is provided so as to be held in the pressure chamber by being supplied from the ink supply passage. In an ink jet printer head in which ink is pressurized by a pressure generating means and ejected from an orifice, the pressure generating means is formed by injection molding of piezoelectric ceramic, so that the pressure generating means made of piezoelectric ceramic is homogeneous. Therefore, it has an effect that it can be mass-produced and can contribute to the improvement of the productivity of the inkjet printer head.

According to a second aspect of the invention, in the first aspect of the invention, the orifice is formed by forming the structural material that forms both the pressure generating means and the orifice by injection molding of piezoelectric ceramic. Since the structural material to be formed is also formed with the pressure generating means, it has an effect that it can further contribute to the improvement of the productivity of the inkjet printer head.

[Brief description of drawings]

FIG. 1 is an exploded perspective view showing a first embodiment of the invention according to claim 1.

FIG. 2 is a perspective view of a main part.

FIG. 3 is an exploded perspective view showing a second embodiment of the invention according to claim 1.

FIG. 4 is a perspective view of a main part.

5 is an exploded perspective view showing a third embodiment of the invention according to claim 1. FIG.

FIG. 6 is a perspective view of a main part.

FIG. 7 is an exploded perspective view showing a fourth embodiment of the invention according to claim 1.

FIG. 8 is a perspective view of a main part.

FIG. 9 is an exploded perspective view showing a fifth embodiment of the invention according to claim 1.

FIG. 10 is a vertical sectional front view.

FIG. 11 is an exploded perspective view showing a sixth embodiment of the invention according to claim 1.

FIG. 12 is a vertical sectional front view.

FIG. 13 is an exploded perspective view showing a seventh embodiment of the invention according to claim 1;

FIG. 14 is an exploded perspective view showing a first embodiment of the invention according to claim 2;

FIG. 15 is a vertical sectional front view.

FIG. 16 is an exploded perspective view showing a second embodiment of the invention according to claim 2;

FIG. 17 is a vertical sectional front view.

FIG. 18 is a vertical sectional side view.

[Explanation of symbols]

1, 11, 20, 32, 43, 52, 63, 72, 80
Inkjet printer head 4,14,27,36,46,59,70,76,84
Pressure chamber 5,15,28,37,47,58,69,77,85
Orifices 7,13,21,22,33,44,55,66,7
3,81 Piezoelectric ceramic 73,81
Structural material

Claims (2)

[Claims] 1. A pressure generating device having at least a surface displacable is provided in a pressure chamber in which an orifice and an ink supply passage communicate with each other, and ink supplied from the ink supply passage and held in the pressure chamber is generated by the pressure generating device. In the ink jet printer head which is pressurized by the above and discharged from the orifice, the pressure generating means is formed by injection molding of piezoelectric ceramic. 2. The method of manufacturing an ink jet printer head according to claim 1, wherein the structural material forming both the pressure generating means and the orifice is formed by injection molding of piezoelectric ceramic.