JPH1034921A - Ink jet recording head and production of elastic plate therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To miniaturize a pressure chamber and to reduce the compliance thereof while ensuring the positioning clearance between the island part of an elastic plate and a piezoelectric vibrator. SOLUTION: The ink jet recording head consists of a spacer 5 demarcating pressure generation chambers 2, ink supply ports 3 and a common ink chamber 4, the elastic plate 1 sealing the opening surface of a spacer 6 to expand and contract the pressure generation chambers 2, the piezoelectric vibrators 20 of a vertical vibration mode coming into contact with the elastic plate 1 and a head case 8 fixing the piezoelectric vibrators 20, the spacer 5 and the elastic plate 1. The elastic plate 1 is constituted of the island part 10 formed on the center line in the longitudinal direction of the pressure generation chambers 2 as a thick-walled part, the thin-walled part 11 formed so as to surround the island part 10 to become an elastical deformation region and a medium thickness part 12 thinner than the island part 10 and thicker than the thin-walled part and the compliance of the pressure generation chambers 2 is reduced by the medium thickness part and the positioning possible region of the leading end of the piezoelectric vibrator is expanded.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet recording head that uses a piezoelectric vibrator that expands and contracts in the axial direction as an actuator to expand and contract a pressure generating chamber to discharge ink droplets from nozzle openings.

[0002]

2. Description of the Related Art An ink jet recording head using a piezoelectric vibrator in a longitudinal vibration mode as an actuator forms a pressure generating chamber B, an ink supply port C, and a common ink chamber D together with a spacer A as shown in FIG. The periphery of the elastic plate E is taken into the thin line portion F on the center line of the pressure generating chamber B,
Providing an island portion G formed with relatively high rigidity,
The piezoelectric vibrator H is brought into contact with the piezoelectric vibrator H to convert the displacement of the piezoelectric vibrator H into a change in volume of the pressure generating chamber with high efficiency. By transmitting the displacement of the piezoelectric vibrator H to the elastic plate E via the island portion G of the elastic plate E, a wide range of the pressure generating chamber B can be efficiently deformed.

In order to improve the print quality of an ink-jet printer, it is necessary to improve the print density and to perform printing with an area gradation by overlapping a plurality of ink droplets. In the former case, it is necessary to increase the arrangement density of the pressure generating chambers, which can be dealt with by reducing the size of the pressure generating chambers. In the latter case, the amount of ink per drop ejected from the nozzle opening can be reduced. This can be dealt with by lowering the compliance of the pressure generating chamber in order to reduce as much as possible. Most of the compliance of the pressure generating chamber is borne by the elastic plate that converts the displacement of the piezoelectric vibrator into a change in the volume of the pressure generating chamber. Therefore, it can be dealt with by reducing the bending displacement region of the elastic plate.

In such a recording head, one end of a plurality of piezoelectric vibrators H is fixed to a fixed substrate N at a constant pitch to constitute a vibrator unit, and this unit is dropped from an opening of a head case M. In addition, a manufacturing method is adopted in which the tips of the plurality of piezoelectric vibrators H are respectively brought into contact with the islands G facing the pressure generating chambers B.

[0005]

For this reason, if there is an error in the pitch of each piezoelectric vibrator H or in the positioning of the elastic plate E, if these errors act in a direction in which they are added, FIG. As indicated by the dotted line J, the piezoelectric vibrator H
Of the elastic plate E, which restricts the vibration area, contacts the thick portion K, which restricts the outside of the vibration area, and the head case M, and the vibration is hindered. There is a fear. The present invention has been made in view of such a problem, and an object thereof is to position a piezoelectric vibrator and an island portion of an elastic plate while reducing the size of a pressure generation chamber and reducing compliance. An object of the present invention is to provide an ink jet recording head capable of increasing a tolerance.

Another object of the present invention is to propose a method of manufacturing an elastic plate suitable for the ink jet recording head.

[0007]

According to the present invention, there is provided a spacer for partitioning a pressure generating chamber, an ink supply port, and a common ink chamber and communicating with a nozzle opening. An elastic plate for sealing the opening surface of the pressure generating chamber to expand and contract the pressure generating chamber, a piezoelectric vibrator in a longitudinal vibration mode abutting on the elastic plate, and fixing the piezoelectric vibrator, the spacer, and the elastic plate. In an ink jet recording head comprising a head case, the elastic plate is formed as a thick portion on a longitudinal center line of the pressure generating chamber, and an elastic deformation region formed to surround the island portion. And an intermediate portion thinner than the island portion and thicker than the thin portion.

[0008]

According to the present invention, the compliance of the pressure generating chamber is reduced by the middle portion between the island portion receiving the displacement of the piezoelectric vibrator and the head case for fixing the elastic plate, so that a minute amount of ink droplet can be formed at a predetermined speed and high. Discharge is performed in a repetitive cycle, and the positionable region of the tip of the piezoelectric vibrator is enlarged.

[0009]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram of a first embodiment of the present invention. Fig. 1 (a), (b)
1 shows an embodiment of the present invention, wherein reference numeral 1 denotes an elastic plate, one surface of a pressure generating chamber 2, an ink supply port 3, and a spacer 5 that partitions a common ink chamber 4. And the flow path unit 7 together with the nozzle plate 6
And the other surface is fixed to the head case 8.

As shown in FIG. 1 (b), the spacer 5 has a contact portion 9a in which a region of the partition wall 9 for partitioning the pressure generating chambers 2, 2, 2 which contacts the elastic plate 1 is made thin. A large elastically deformable region is secured in the elastic plate 1 in a region facing each pressure generating chamber 2 so that ink droplets are efficiently ejected from the nozzle openings 14.

As shown in FIG. 2, the elastic plate 1 has an island portion 10 formed of a thick portion extending in the longitudinal direction of the pressure generating chamber 2 in a region facing the pressure generating chamber 2 so as to surround the same. A thin portion 11 serving as an elastic deformation region is formed at the bottom. On the outer periphery of the thin portion 11, an intermediate portion 12 thinner than the island portion 10 and thicker than the thin portion 11, that is, a region thinner by ΔH than the island portion 10, is formed.
Further, a thick portion 13 similar to the island portion 10 is formed at a position facing the partition 9 of the outer spacer 5.

Numeral 20 denotes a piezoelectric vibrator. In this embodiment, a piezoelectric material 21 and electrodes 22 and 23 forming two poles are alternately laminated so as to be longitudinally vibrated, that is, displaced in the longitudinal direction. As shown in FIG. 3 above, the plurality of piezoelectric vibrators 2
Numeral 0 is fixed to the fixed substrate 24 so as to match the arrangement pitch of the island portions 10 and is configured as a vibrator unit 25. The tip 20a is fixed to the above-described island portion with an adhesive, and It is also fixed to the head case 8.

In this embodiment, the flow path unit 7 is fixed to a predetermined position of the head case 8, the head case 8 is positioned so that the flow path unit 7 faces downward, and the flow path unit 7 is bonded to the front end 20 a of each piezoelectric vibrator 20. When the vibrator unit 25 is dropped from the opening 8a of the head case 8 by applying the agent, the grooves and recesses provided in the head case 8 and the piezoelectric vibrator 2
The tip 20a of the dummy piezoelectric vibrator 26, which is located at both ends of the vibrator unit 25 as shown in FIG.
And the vibrator unit 25 is positioned at a specified position.

As a result, each piezoelectric vibrator 20 has an island portion 1 provided opposite to each pressure generating chamber 2.
0 is in contact with an adhesive. In this state, an adhesive is poured into a gap between the head case 8 and the fixed substrate 24 to fix the vibrator unit 25 to the head case 8, thereby completing the recording head.

An intermediate portion 12 is formed between the island portion 10 and the head case 8, and a thin portion 1 is provided between the tip 20a of the piezoelectric vibrator 20 and the head case 8.
In addition to the clearance 1, there is a clearance corresponding to the widths ΔL1 and ΔL2 in the longitudinal direction of the pressure generating chamber 2 of the medium thickness portion 12,
Even if there is a positioning error between the vibrator unit 25 and the flow path unit 7, it is absorbed by the widths ΔL1 and ΔL2,
Without bringing the piezoelectric vibrator 20 into contact with the thick portion 13 and the head case 8 other than the island portion 10,
Can be fixed to zero.

In the arrangement direction of the pressure generating chambers 2,
2, the clearances corresponding to the widths ΔL3 and ΔL4 exist.
And a positioning error can be absorbed.

Needless to say, the size of the piezoelectric vibrator 20 is larger than the size of the island portion 10 and the rigidity of the island portion 10 is much higher than that of the thin portion 11, so that the size of the Even if the position shift occurs,
The displacement of the piezoelectric vibrator 20 can be converted into a change in the volume of the pressure generating chamber 2.

By forming the solid portion in the region facing the pressure generating chamber 2 as described above, not only can the positioning tolerance between the piezoelectric vibrator and the flow path unit be enlarged, but also the deformable region can be formed by the solid portion. It is possible to limit the compliance of the pressure generating chamber and to greatly reduce the compliance.

For example, if the rigidity of the middle portion 12 is set to be at least 20 times the rigidity of the thin portion 11, the compliance of the pressure generating chambers of the same size can be reduced to 50% or less.
Fine ink droplets of 10 nanograms or less can be ejected from a nozzle opening having a diameter of 25 μm or more at a flight speed of 7 m / s or more.

In the above-described embodiment, the region facing the partition wall 9 that partitions the adjacent pressure generating chambers 2 is formed as the thick portion 13. However, as shown in FIG. Although thick portions are formed at both ends in the longitudinal direction,
The thick portion 13 in the region facing the partition 9 is omitted, and the
May be formed to have the same opening surface.

According to this embodiment, even if there is a slightly large error in the arrangement pitch of the piezoelectric vibrators 20, the piezoelectric vibrators 20
Does not come into contact with the thick portion in the direction in which the pressure generating chambers 2 are arranged, not only can the assembly tolerance be increased, but also the formation of the thick portion 13 that partitions the direction in which the pressure generating chambers 2 are arranged can be achieved. It becomes unnecessary and the manufacturing process of the elastic plate can be simplified.

Next, an embodiment of a method for manufacturing the above-mentioned elastic plate will be described with reference to FIG. A stretched polymer film 31 having a thickness of several μm that can function as the thin portion 11 is laminated on the surface of the base film 30 serving as a work base (I), and a surface of the stretched polymer film 31 having a thickness of 2000 to 3000 Å A conductive layer 32 of copper or nickel or copper and nickel is formed by sputtering to a thickness (I
I).

Forming a resist layer on the surface of the conductive layer 32;
The pattern for forming the medium-thickness portion 12, the island portion 10, and the thick-thickness portion 13 is exposed to form an electroforming mask 34 having a window 33 in these regions (III). Since the metal plating layer 35 is formed on the metal layer 12, the process is continued until the thickness of the middle portion 12 becomes (IV).

The mask 34 is removed (V), and the process (I)
In the same manner as in II), the island portion 10 and the thick portion 13
Electroforming mask 37 having window 36 only in the region where
Is formed (VI), and electroforming 38 is performed again until the thickness as the island portion 10 and the thick portion 13 is reached (VII).
The elastic plate is completed by removing the mask 37 and removing it from the base film 30 (VIII).

FIG. 6 shows another embodiment of the method of manufacturing the elastic plate 1. A stretched film 40 having a thickness of several μm made of a polymer resin such as polyimide or PPS, and a metal plate having a thickness exhibiting optimum rigidity as an island portion 10 made of, for example, non-rust steel having ink resistance, for example, a metal plate having a thickness of 60 μm 4
1 are laminated via an adhesive layer 42 having a thickness of about 1 to 2 μm (I).

An etching protection film 44 having a window 43 corresponding to a region to be the thin portion 11 is formed on the surface of the metal plate 41, and etching is performed (II). Thereby, the metal plate 41
Is formed to a depth such that the remaining portion can function as the thin portion 11, and in this embodiment, a concave portion 45 reaching the adhesive layer 42 is formed.

The etching protection film 44 is removed, and the
An etching protection film 47 having a window 46 is formed only in a region corresponding to 2 (III), and etching is performed until the metal plate 41 is formed with a step portion 48 having a thickness suitable for the middle wall portion 12 ( V).

Then, when the etching protective film 47 is removed, the stretched polymer film 40 and the adhesive layer 42 are turned into the thin portion 11, and the elastic portion having the island portion 10 and the thick portion 13 where the thickness of the metal plate 41 is high is provided. The board is completed (V).

FIG. 7 shows another embodiment of the method of manufacturing the elastic plate 1. As shown in FIG. A stretched film 50 having a thickness of several μm made of a polymer resin such as polyimide or PPS, and a metal plate 51 having a thickness of, for example, 60 μm which has an ink resistance and exhibits optimum rigidity as an island portion made of, for example, rustless steel. Are laminated via an adhesive layer 52 (I).

An etching protection film 54 having a window 53 corresponding to a region to be the thin portion 11 and the middle portion 12 is formed on the surface of the metal plate 51 so that the metal plate 51 can function as the middle portion 12. A concave portion 55 having a thickness is formed by etching (II).

The thin portion 1 is removed by removing the etching protection film 54.
(III), and etching is performed until the metal plate 51 has a thickness suitable for the thin portion 11 (V).
I).

When the etching protection films 57 and 58 are removed, the stretched polymer film 50 and the adhesive layer 52 are turned into the thin portion 11, and the step 59 formed by the recess 55 is turned into the middle portion 1.
2, and an elastic plate including the island portion 10 having the thickness of the metal plate 51 and the thick portion 13 is completed (V).

FIG. 8 shows another embodiment of the method of manufacturing the elastic plate 1, which comprises a stretched film 60 having a thickness of several μm made of a polymer resin such as polyimide, PPS, etc. A metal plate 61 having a thickness of, for example, 30 μm that exhibits rigidity as the medium-wall portion 12 is laminated via an adhesive layer 62 (I).

An etching protective film 64 having a window 63 is formed on the surface of the metal plate 61 so as to coincide with the outer periphery of the region to become the thin portion 11, and a concave portion 65 reaching the adhesive layer 62 is formed by etching (II). ).

After removing the etching protection film 64, a photosensitive dry film 67 whose thickness matches the height of the island portion 10 is laminated (III).

For example, the region of the island portion is exposed using a mask or the like so that the region other than the region where the island portion 10 is to be formed of the dry film 67 can be removed, and the dry film 67 other than the island portion is removed (IV). .

As a result, the adhesive layer 62 serving as the thin portion 11 and the metal plate 62 serving as the middle portion are exposed together with the film 60. Therefore, the film 67 is irradiated with ultraviolet rays while being heated, or irradiated with an electron beam. Is performed to harden the photosensitive dry film 67 remaining in the region that will become the island portion 10, and then the head case 8 is fixed at the position indicated by the chain line in the figure so as to leave the middle portion (V).

FIG. 9 shows another embodiment of the method of manufacturing the elastic plate 1, in which a stretched film 70 made of a polymer resin such as polyimide or PPS and having a thickness of several μm, and a stretched film 70 together with a middle film. A metal plate 71 having a thickness exhibiting optimal rigidity, for example, 30 μm, is laminated via the adhesive layer 72 as the meat portion 12 (I).

An etching protective film 64 having a window 73 is formed on the surface of the metal plate 71 so as to coincide with the outer periphery of the region to be the thin portion 11. In this embodiment, the thin portion 11 has an optimum thickness. Recess 75 reaching adhesive layer 72
Is formed by etching (II).

The first photosensitive dry film 76 having a thickness substantially equal to that of the metal plate 71 by removing the etching protection film 74.
And exposure is performed so that regions 76a and 76b serving as the island portion 10 and the thick portion 13 can remain (II).
I).

The second photosensitive dry film 77 is laminated on the surface of the first photosensitive dry film 76, and is exposed using a mask or the like so that the region 77a where the island portion 10 is to be formed remains. Then, unnecessary regions of the first and second photosensitive dry films 76 and 77 are removed (IV).

As a result, the adhesive layer 72 serving as the thin portion 11 and the metal plate 71 serving as the middle portion are exposed together with the film 70. Then, the regions 76a and 76 remaining without being removed
The photosensitive dry films 76 and 77 b and 77 a are irradiated with ultraviolet rays while being heated, or are cured by irradiating electron beams to form the island portions 10 and the thick portions 13 (V).

FIG. 10 shows another embodiment of the method of manufacturing the elastic plate 1. The stretched film 80 having a thickness of several μm made of a polymer resin such as polyimide or PPS and the island portion 10 are optimally used. Thickness with great rigidity, for example, 30
A metal plate 81 of μm is laminated via an adhesive layer 82 (I).

An etching protection film 84 having a window 83 is formed on the surface of the metal plate 81 so as to coincide with the outer periphery of the region serving as the solid portion 12, and a concave portion 85 reaching the adhesive layer 82 is formed by etching ( II).

The etching protection film 84 is removed to remove the middle portion 1
For example, a first photosensitive dry film 86 having a thickness suitable for 2 is laminated, and, for example, an area other than the thin portion area is exposed so that the thin portion can be removed. The second photosensitive dry film 87 whose total thickness with the first photosensitive dry film 86 matches the height of the island portion 10 is laminated so as to fill the concave portions (III).

The island portion forming region is exposed using a mask or the like so that the region where the island portion 10 of the second dry film 87 is to be formed is left, and then the second dry film 87 other than the island portion is exposed. (IV).

Next, the first dry film 86 in the thin portion forming region is removed. After that, the first and second photosensitive dry films 86 remaining in the region of the island portion 10,
87 and the first photosensitive dry film 86 remaining in the region of the inner wall portion 12 are cured by irradiating with ultraviolet rays or irradiating with an electron beam while heating (V).

As a result, an elastic plate having an island portion 10 and a medium portion 12 of a polymer material on the surface of the metal plate 80 which can be elastically deformed is completed.

FIG. 11 shows another embodiment of the method of manufacturing the elastic plate 1. The stretched film 90 having a thickness of several μm made of a polymer resin such as polyimide or PPS and the island portion 10 are optimal. Thickness with great rigidity, for example, 30
A μm metal plate 91 is laminated via an adhesive layer 92 (I).

An etching protective film 94 having a window 93 is formed on the surface of the metal plate 91 so as to coincide with the outer periphery of the region serving as the solid portion 12, and a concave portion 95 reaching the adhesive layer 92 is formed by etching ( II).

The etching protection film 94 is removed, and the
The first photosensitive dry film 96 having a thickness suitable for No. 2 is laminated. Among the regions located in the concave portions 95 of the first photosensitive dry film 96, the island portion 10 and the medium portion 12
Is exposed using a mask provided with a window other than the region to be
6a and 96b are exposed (III).

Next, the second photosensitive dry film 97 is laminated, and the region 97a to be the island portion 10 is selectively exposed (IV), and the first and second photosensitive dry films 9 are formed.
When the unexposed areas 6 and 97 are removed, the film 90 and the adhesive layer 92 are turned into the thin portion 11, and the laminate of the film 90, the adhesive layer 92, and the first photosensitive dry film 96 is turned into the middle portion. 12, and an elastic plate is completed in which the laminate of the film 90, the adhesive layer 92, the first photosensitive dry film 96, and the second photosensitive dry film 97 is the island portion 10.

When a photosensitive dry film is laminated, a gap 99 may be formed between the photosensitive dry film and the etched surface 98 of the metal plate 91, and a gap 99 may be formed due to a deviation in exposure position. However, this gap is extremely small. Does not substantially affect compliance.

Since the elastic plate is formed of the metal plate 91 except for a region which can be deformed opposite to the pressure generating chamber, the overall rigidity is large, which helps to prevent crosstalk.

FIG. 12 shows another embodiment of the method of manufacturing the elastic plate 1, in which the base 100 is made of polyimide, PP, or the like.
Stretched film 1 made of a polymer resin such as S and having a thickness of several μm
01 (I), and a metal layer 1 is formed on this surface by vapor deposition or the like.
02 (II). The first photosensitive dry film 103 is attached to the surface of the metal layer 102, and the island portion 1
0, regions 103a and 10 that become medium thickness portion 12 and thick thickness portion 13
3b is selectively exposed (III).

A second photosensitive dry film 104 is adhered to the surface of the first photosensitive dry film 103, and a region corresponding to the island portion 10 and the thick portion 13 is selectively exposed (IV).

The unexposed area is removed, and the island portion 10 is irradiated by irradiating ultraviolet rays while heating or irradiating an electron beam.
Then, the photosensitive dry films 103a, 103b, 104a, and 104b remaining in the region to be the middle portion 12 are cured (V) and removed from the base 100 to complete the elastic plate (VI).

FIG. 13 shows another embodiment of a method of manufacturing an elastic plate, in which a first photosensitive dry film 111 is attached to a surface of a metal plate 110 having a thickness capable of functioning as a thin portion 11. Island part 10, medium meat part 1
2. The regions 111a and 111b to be the thick portions 13 are selectively exposed (II).

A second photosensitive dry film 112 is adhered to the surface of the first photosensitive dry film 111, and a region 112a corresponding to the island portion 10 and the thick portion 13 is formed.
112b is selectively exposed (III).

The unexposed area is removed and ultraviolet rays are irradiated while heating, or an electron beam is irradiated to the island section 10.
When the photosensitive dry films 111a, 111b, 112a, and 112b remaining in the region to be the middle portion 12 are cured, the elastic plate is completed (IV).

FIG. 14 shows another embodiment of the ink jet recording head according to the present invention. In this embodiment, the middle portion 12 is formed so as to be continuous with the island portion 10 and the thin portion 11 is formed. Is extended to a contact area with the head case 8.

In this embodiment, since the middle portion 12 is formed continuously with the island portion 10 and the thin portion 11 is located on the outer periphery, the positioning of the piezoelectric vibrator 20 in the longitudinal direction of the pressure generating chamber 2 is performed. The tolerance can be increased, and the displacement of the piezoelectric vibrator 2 can be controlled not only by the island portion 10 but also by the middle portion 12.
Can be transmitted to the elastic plate 1 via the pressure generating member, and the volume change rate of the pressure generating chamber 2 can be increased.

FIG. 15 shows another embodiment of the present invention. In this embodiment, an inner wall portion 12 is provided inside an island portion 10 and a partition wall 9 for partitioning the pressure generating chamber 2.
12 'is formed, and a thin portion 11 is formed in a region surrounded by the medium thickness portion.

According to this embodiment, since the middle portions 12 and 12 ′ are interposed between the island portion 10 and the thin portion 11, the positioning tolerance of the piezoelectric vibrator 20 in the longitudinal direction of the pressure generating chamber 2 is enlarged. In addition to being able to reduce stress concentration at the boundary between the island portion 10 and the thin portion 11, it is possible to reduce fatigue and prevent breakage even when the thin portion 11 is made of a polymer film or the like. can do.

In the above embodiment, the elastic plate 1
The side facing the pressure generating chamber 2 is flat, and the piezoelectric vibrator 2
The unevenness is formed only on the side of the surface opposite to 0,
Although the middle portion 12 is provided, as shown in FIG. 16, the surface facing the piezoelectric vibrator 20 has the same height as the thick portion 13 and the island portion 10, and the thin portion 11 By forming only the surface having the same height and forming the concave portion 29 on the surface facing the pressure generating chamber 2, the island portion 10 is formed.
The thin portion 11 can be formed so as to be continuous with the middle portion 12, and the middle portion 12 can be formed so as to be continuous with the thick portion 13.

In this embodiment, there is no member higher than the island portion 10 between the island portion 10 and the head holder 8 on the surface facing the piezoelectric oscillator 20. The positioning tolerance 20 can be enlarged by ΔL1 and ΔL2 in the longitudinal direction of the pressure generating chamber 2 and by ΔL3 and ΔL4 in the arrangement direction of the pressure generating chambers 2. Furthermore, in this embodiment, the volume of the pressure generating chamber 2 can be increased by the volume of the concave portion 29, and the size of the pressure generating chamber 2 can be reduced.

FIG. 17 shows an embodiment of the method of manufacturing the above-mentioned diaphragm, which has a thickness of several μm and is made of a polymer resin such as polyimide or PPS having a thickness capable of functioning as the thin portion 11. Metal plates 123 and 124 are laminated on both sides of the stretched film 120 via adhesive layers 121 and 122 (I),

On the surface of one metal plate 123, an etching protection film 126 having a window 125 is formed in a region which is to connect the island portion and the thick portion (II). In addition, an etching protection film 128 having a window 127 is formed on the surface of the other metal plate 124 in a region that becomes a concave portion facing the pressure generating chamber side (III).

The recesses 129 are formed by etching both metal plates simultaneously or from one of the metal plates (I).
V), when the etching protection films 126 and 128 are removed (V), the film 120 becomes the thin portion 11 and the metal plate 12
The metal plate 123 remaining in the region opposed to the concave portion of No. 4 is referred to as the island portion 10, and the portion remaining in the region of the metal plate 123 facing the concave portion is referred to as the medium portion 12.
The diaphragm in which the portion where both 3 and 124 remain are made the thick portion 13 is completed.

FIG. 18 shows another embodiment of the present invention. In this embodiment, the diaphragm 1 is the same as that shown in FIG.
As shown in FIG. 3, only the thin portion and the island portion are formed in the direction in which the pressure generating chambers are arranged, and the medium portion 12 and the thick portion 1 are formed.
3 is not formed, and only the middle portion 12 and the thick portion 13 are formed only in the longitudinal direction of the pressure generating chamber 2.

According to this embodiment, the positioning tolerance in the longitudinal direction of the pressure generating chamber 2 can be enlarged by the widths ΔL1 and ΔL2 of the inner wall portions 12 formed in the direction in which the pressure generating chambers 2 are arranged. 2 can be set larger than the enlarged amounts ΔL3 and ΔL4 in the above-described embodiment, and can be fixed without impairing the function even if there is a slight error in the arrangement pitch of the piezoelectric vibrators 20. In addition to the above, it is not necessary to form a middle portion or a thick portion in the direction in which the pressure generating chambers 2 are arranged. Can be simplified.

In the above embodiment, the recording head having the nozzle opening in the displacement direction of the piezoelectric vibrator has been described as an example. However, the axial direction of the pressure generating chamber, that is, the direction orthogonal to the displacement direction of the piezoelectric vibrator. It is apparent that the same effect can be obtained even when the present invention is applied to a recording head provided with a nozzle opening.

Further, in the above-described embodiment, when a polymer film and a metal plate are laminated to form a substrate, they are joined via an adhesive layer. However, an adhesive polymer film may be used. Further, by applying and drying a polymer material on a metal plate, an adhesive layer can be made unnecessary.

As the film film functioning as the thin portion, a metal film such as nickel, titanium, non-rusting steel, and copper can be used in addition to the polymer film.

[0075]

As described above, in the present invention,
A pressure generating chamber, an ink supply port, and a spacer that partitions the common ink chamber and communicates with the nozzle opening; an elastic plate that seals an opening surface of the spacer to expand and contract the pressure generating chamber;
In an ink jet recording head including a piezoelectric vibrator in a longitudinal vibration mode in contact with an elastic plate, and a head case for fixing the piezoelectric vibrator, the spacer, and the elastic plate, the elastic plate is positioned on a longitudinal center line of the pressure generating chamber. An island portion formed as a thick portion, a thin portion formed so as to surround the island portion to be an elastic deformation region, and an intermediate portion thinner than the island portion and thicker than the thin portion. Therefore, compliance can be reduced by a solid portion between the island portion that receives the displacement of the piezoelectric vibrator and the head case that fixes the elastic plate, and a minute amount of ink droplet can be ejected at a high repetition frequency. Not only that, the region where the tip of the piezoelectric vibrator can be positioned can be enlarged to simplify the assembly process and improve the manufacturing yield.

[Brief description of the drawings]

FIGS. 1A and 1B are cross-sectional views of a vicinity of a pressure generating chamber in a longitudinal direction of the pressure generating chamber and an arrangement direction of the pressure generating chamber, showing one embodiment of the present invention.

FIG. 2 is a perspective view showing one embodiment of an elastic plate used in the recording head.

FIGS. 3A and 3B are diagrams showing one embodiment of a vibrator unit used for the recording head, respectively.

FIG. 4 is a perspective view showing another embodiment of the elastic plate.

FIGS. 5 (I) to (VIII) are diagrams showing one embodiment of a method of manufacturing the elastic plate, respectively.

FIGS. 6 (I) to 6 (V) are views showing another embodiment of the method of manufacturing the elastic plate.

FIGS. 7 (I) to 7 (V) are views showing one embodiment of a method of manufacturing an elastic plate according to the present invention.

FIGS. 8 (I) to (V) are views showing one embodiment of a method of manufacturing the elastic plate, respectively.

FIGS. 9 (I) to 9 (V) are views showing one embodiment of a method of manufacturing the elastic plate, respectively.

FIGS. 10 (I) to (V) are views showing one embodiment of a method for manufacturing the elastic plate, respectively.

FIGS. 11 (I) to (V) are views showing one embodiment of a method of manufacturing the above elastic plate.

FIGS. 12 (I) to (VI) are views showing one embodiment of a method of manufacturing an elastic plate same as above.

FIGS. 13 (I) to (IV) are diagrams showing one embodiment of a method of manufacturing the elastic plate, respectively.

FIG. 14 is a view showing another embodiment of the present invention in the form of an elastic plate.

FIG. 15 is a view showing another embodiment of the present invention in the form of an elastic plate.

FIGS. 16A and 16B are cross-sectional views of the vicinity of the pressure generating chamber in the longitudinal direction of the pressure generating chamber and the arrangement direction of the pressure generating chamber, respectively, showing another embodiment of the present invention.

FIGS. 17 (I) to (V) are diagrams showing steps of manufacturing an elastic plate of the recording head, respectively.

FIGS. 18A and 18B are cross-sectional views of the vicinity of the pressure generating chamber in the longitudinal direction of the pressure generating chamber and the arrangement direction of the pressure generating chambers, respectively, showing another embodiment of the present invention.

FIG. 19 is a perspective view showing an embodiment of the elastic plate of the recording head.

FIGS. 20A and 20B are a cross-sectional view and a top view showing an example of a conventional ink jet recording head and an elastic plate, respectively.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Elastic plate 2 Pressure generating chamber 3 Ink supply port 4 Common ink chamber 5 Spacer 6 Nozzle plate 7 Flow path forming unit 8 Head case 9 Partition wall 10 Island part 11 Thin part 12 Medium part 13 Thick part 14 Nozzle opening 20 Piezoelectric Vibrator

Claims (21)

[Claims] A spacer that partitions a pressure generating chamber, an ink supply port, and a common ink chamber and communicates with a nozzle opening;
An elastic plate that seals the opening surface of the spacer to expand and contract the pressure generating chamber, a piezoelectric vibrator in a longitudinal vibration mode that abuts the elastic plate, the piezoelectric vibrator and the spacer,
And a head case for fixing the elastic plate, wherein the elastic plate surrounds the island portion formed as a thick portion on the longitudinal center line of the pressure generating chamber, and the island portion. An ink jet recording head comprising a thin portion formed as an elastic deformation region and a middle portion thinner than the island portion and thicker than the thin portion. 2. The ink jet recording head according to claim 1, wherein the thin portion is formed so as to be continuous with the island portion, and the middle portion is formed so as to surround the thin portion. 3. The ink jet recording head according to claim 1, wherein the middle portion is formed so as to be continuous with the island portion, and the thin portion is formed so as to surround the middle portion. 4. The ink jet recording head according to claim 1, wherein the thin portion, the medium portion, and the island portion are formed by etching the same plate material. 5. The ink jet recording head according to claim 1, wherein the thin portion is formed of a metal plate, and the island portion is formed by laminating a polymer material on the thin portion. 6. The ink jet recording head according to claim 5, wherein said polymer material is a photosensitive film. 7. The ink jet recording according to claim 1, wherein the thin portion is formed of a polymer film, and the medium portion and the island portion are formed by etching a metal laminated on the polymer film. head. 8. The thin portion is made of a polymer film, and the island portion is made of a metal laminated on the thin portion.
2. The ink jet recording head according to claim 1, wherein said middle portion is made of a polymer material laminated on said thin portion. 9. The ink jet recording head according to claim 8, wherein the polymer material is a photosensitive film. 10. The method according to claim 1, wherein the island portion is formed by laminating a polymer material on the thin portion, and a contact region with the head case is formed by laminating a metal on the thin portion. The inkjet recording head according to the above. 11. A step of forming a resist layer on a surface of a film having a thickness capable of functioning as a thin portion, exposing a pattern for forming a middle portion and a thick portion to form an electroforming mask, and A step of performing electroforming until the thickness of the thick portion is reached; a process of removing the mask to form an electroforming mask having a window only in the region where the thick portion is formed; A method for producing an elastic plate of an ink jet recording head comprising: 12. A step of forming a substrate by laminating a film having a thickness capable of functioning as a thin portion and a metal plate, and forming an etching protection film having a window corresponding to a region to be a thin portion on the surface of the metal plate. Forming a recess having a thickness suitable for the thin portion in the metal plate by etching; removing the etching protection film to form an etching protection film having a window in a region corresponding to the medium thickness portion; And a step of etching the metal plate until a thickness suitable for the middle portion is formed. 13. A step of forming a substrate by laminating a film having a thickness capable of functioning as a thin portion and a metal plate, and having a window corresponding to a region to be a thin portion and a medium portion on the surface of the metal plate. Forming an etching protection film, forming a concave portion having a thickness suitable for the middle portion in the metal plate by etching, and removing the etching protection film in a region corresponding to a thin portion of the middle portion. A method of manufacturing an elastic plate for inkjet recording, comprising: a step of forming an etching protective film having a window; and a step of etching until the middle portion has a thickness suitable for a thin portion. 14. A step of laminating a film having a thickness capable of functioning as a thin portion and a metal plate to form a substrate, and an etching protective film having a window corresponding to an outer periphery of a region to be a thin portion on the surface of the metal plate. Forming the concave portion by etching the metal plate to a thickness suitable for the thin portion; removing the etching protection film to the concave portion, the thickness of the concave portion being larger than that of the metal plate and the island portion. A step of laminating a photosensitive dry film having a thickness capable of functioning as a step, and a step of exposing so that a groove of the dry film can be removed and removing a region to be a thin part, Production method. 15. A step of laminating a film having a thickness suitable for a thin portion and a metal plate to form a substrate, and an etching protective film having a window corresponding to an outer periphery of a region to be a thin portion on the surface of the metal plate. Forming a concave portion by etching the metal plate to a thickness suitable for the thin portion; and laminating a first photosensitive dry film in the concave portion by removing the etching protective film. Exposing an area corresponding to the island portion and the medium thickness portion; and laminating a second photosensitive dry film having a total thickness of the first photosensitive dry film serving as the island portion. Exposing a region where an island portion of the second photosensitive dry film is to be formed; removing the second photosensitive dry film in a region corresponding to a thin portion and a medium portion; Removing the first photosensitive dry film parts region, the manufacturing method of the elastic plate of the ink jet recording head comprising a. 16. A step of forming a substrate by laminating a film having a thickness capable of functioning as a thin portion and a metal plate, and having a window on a surface of the metal plate so as to coincide with an outer periphery of a region to be a middle portion. Forming an etching protection film, forming a recess in the metal plate by etching to a thickness suitable for the thin portion, and removing the etching protection film to remove the etching protection film. A step of laminating a photosensitive dry film, a step of exposing to enable removal of a thin-walled area, and a second step in which the total thickness of the first photosensitive dry film matches the height of the island section. Laminating a photosensitive dry film, exposing a second photosensitive dry film to enable removal of the region of the thin portion and the medium portion, and removing the region of the region removed by the exposure. 1, the first Process and method of the elastic plate of the ink jet recording head consisting of removing the photosensitive dry film. 17. A step of forming a metal layer on a film having a thickness capable of functioning as a thin part, a step of laminating a first photosensitive dry film having a thickness suitable for a medium part on the metal layer, Exposing the region to make it possible to remove an area, laminating a second photosensitive dry film having a total thickness equal to the height of the island portion with the first photosensitive dry film, Exposing the second photosensitive dry film to make it possible to remove the region of the inner and middle portions, and removing the first and second photosensitive dry films in the region that has become removable by the exposure. A method for manufacturing an elastic plate of an ink jet recording head, comprising: 18. A step of laminating a first photosensitive dry film having a thickness capable of functioning as a medium part on a substrate having a thickness capable of functioning as a thin part, and exposing to enable removal of a region to be a thin part. A step of laminating a second photosensitive dry film having a total thickness of the first photosensitive dry film equal to the height of the island part; and enabling removal of the thin part and the medium part. Exposing the second photosensitive dry film to the first photosensitive dry film, and removing the first and second photosensitive dry films in the areas removable by the exposure. Production method. 19. A spacer that partitions a pressure generating chamber, an ink supply port, and a common ink chamber and communicates with a nozzle opening, and an elasticity that seals an opening surface of the spacer to expand and contract the pressure generating chamber. An ink jet recording head comprising a plate, a piezoelectric vibrator in a longitudinal vibration mode in contact with the elastic plate, and a head case for fixing the piezoelectric vibrator, the spacer, and the elastic plate, wherein the elastic plate generates the pressure An island portion formed as a thick portion on the center line in the longitudinal direction of the chamber, a thin portion formed to surround the island portion to be an elastic deformation region, and a thinner portion than the island portion, and An ink jet recording head comprising a concave portion formed on a surface facing the pressure generating chamber so as to form a thick middle portion. 20. A step of attaching a metal plate having at least a thickness functioning as an island portion to both surfaces of a film having a thickness capable of functioning as a thin portion to form a substrate; Forming an etching protective film having a window corresponding to the outer periphery of the region to be a portion, and forming an etching protective film having a window corresponding to the outer periphery of the region to be a thin portion on the surface of the other metal plate, Forming a concave portion in the metal plate by the etching; and a method of manufacturing an elastic plate of an ink jet recording head. 21. A spacer that partitions a pressure generation chamber, an ink supply port, and a common ink chamber and communicates with a nozzle opening, and an elasticity that seals an opening surface of the spacer to expand and contract the pressure generation chamber. An ink jet recording head comprising a plate, a piezoelectric vibrator in a longitudinal vibration mode in contact with the elastic plate, and a head case for fixing the piezoelectric vibrator, the spacer, and the elastic plate, wherein the elastic plate generates the pressure In the direction in which the chambers are arranged, a plurality of island portions are provided with which the piezoelectric vibrator abuts with a thin portion serving as an elastically deformable region interposed therebetween. An ink jet recording head formed by forming a middle portion thinner than the thin portion and thicker than the thin portion.