JP2000052550A - Ink-jet type recording head and ink-jet type recording apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ink-jet type recording head and an ink-jet type recording apparatus in which an amount of deformation of a diaphragm is improved without deteriorating a durability of the diaphragm. SOLUTION: In the ink-jet type recording head having a passage formation substrate 10 where pressure generation chambers 12 communicating with nozzle openings are partitioned and piezoelectric elements 300 set to one face of the passage formation substrate 10 via a diaphragm, a beam part 100 of projections extending in a plan direction is set at least to an upper part of the diaphragm, whereby an amount of deformation and a durability of the diaphragm are improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a part of a pressure generating chamber which communicates with a nozzle opening for discharging ink droplets, which is constituted by a vibrating plate, and a piezoelectric element is formed on the surface of the vibrating plate. The present invention relates to an ink jet recording head and an ink jet recording apparatus that eject ink droplets by displacement.

[0002]

2. Description of the Related Art A part of a pressure generating chamber communicating with a nozzle opening for discharging ink droplets is constituted by a vibrating plate, and the vibrating plate is deformed by a piezoelectric element to pressurize the ink in the pressure generating chamber to pass through the nozzle opening. Two types of ink jet recording heads that eject ink droplets have been commercialized, one using a longitudinal vibration mode piezoelectric actuator that expands and contracts in the axial direction of the piezoelectric element, and the other using a flexural vibration mode piezoelectric actuator. ing.

In the former method, the volume of the pressure generating chamber can be changed by bringing the end face of the piezoelectric element into contact with the diaphragm, so that a head suitable for high-density printing can be manufactured. There is a problem in that a difficult process of cutting into a comb shape in accordance with the arrangement pitch of the openings and an operation of positioning and fixing the cut piezoelectric element in the pressure generating chamber are required, and the manufacturing process is complicated.

On the other hand, in the latter, a piezoelectric element can be formed on a diaphragm by a relatively simple process of sticking a green sheet of a piezoelectric material according to the shape of a pressure generating chamber and firing the green sheet. In addition, there is a problem that a certain area is required due to the use of flexural vibration, and that high-density arrangement is difficult.

On the other hand, in order to solve the latter disadvantage of the recording head, a uniform piezoelectric material layer is formed by a film forming technique over the entire surface of the diaphragm as disclosed in Japanese Patent Application Laid-Open No. 5-286131. A proposal has been made in which the piezoelectric material layer is cut into a shape corresponding to the pressure generating chambers by a lithography method, and a piezoelectric element is formed so as to be independent for each pressure generating chamber.

This eliminates the need for attaching the piezoelectric element to the vibration plate, which not only allows the piezoelectric element to be manufactured by a precise and simple method such as lithography, but also reduces the thickness of the piezoelectric element. There is an advantage that it can be made thin and can be driven at high speed. In this case, the piezoelectric element corresponding to each pressure generating chamber can be driven by providing at least only the upper electrode for each pressure generating chamber while the piezoelectric material layer is provided on the entire surface of the vibration plate.

[0007]

By the way, in the above-mentioned ink jet recording head, in order to improve the displacement efficiency of the diaphragm by driving the piezoelectric actuator, the diaphragm corresponding to both sides of the piezoelectric element is provided. A thinning structure has been proposed.

However, when the thickness of the portions corresponding to both sides of the piezoelectric element, that is, the so-called diaphragm arm portion, is reduced, the displacement is improved, but there is a problem that the strength and durability are reduced.

In view of such circumstances, an object of the present invention is to provide an ink jet recording head and an ink jet recording apparatus in which the amount of deformation of a diaphragm is improved without reducing the durability of the diaphragm. .

[0010]

According to a first aspect of the present invention, there is provided a flow path forming substrate in which a pressure generating chamber communicating with a nozzle opening is defined, and one surface of the flow path forming substrate. A piezoelectric element provided through a vibration plate to generate a pressure change in the pressure generating chamber, wherein at least an upper portion of the vibration plate has a beam portion formed of a ridge extending in a surface direction. Is provided in the ink jet recording head.

In the first aspect, the strength is improved while the weight of the diaphragm is reduced by the beams.

According to a second aspect of the present invention, in the first aspect, the beam portion is provided on at least both sides in the width direction of the piezoelectric element in at least a region of the diaphragm facing the pressure generating chamber. An ink jet recording head is characterized in that:

According to the second aspect, the durability of the diaphragm is improved without hindering the deformation of the diaphragm due to the driving of the piezoelectric element.

According to a third aspect of the present invention, in the first or second aspect, the beam portion is provided over the entire upper portion of the diaphragm except for a region corresponding to the piezoelectric element. And an ink jet recording head.

In the third aspect, the strength of the entire diaphragm can be maintained while reducing the weight, and the reliability of the head is improved.

According to a fourth aspect of the present invention, in any one of the first to third aspects, the beam portion forms a geometric pattern, and at least a part of a region other than the beam portion in the thickness direction is removed. The ink jet recording head is characterized in that it has a concave portion formed.

In the fourth aspect, durability is maintained by the beam portion, and the formation of the concave portion reduces the weight of the diaphragm and improves characteristics such as the responsiveness of the head.

According to a fifth aspect of the present invention, in any one of the first to fourth aspects, the diaphragm comprises an elastic film and a lower electrode, and the beam portion is formed on the lower electrode. The feature is the ink jet recording head.

In the fifth aspect, the characteristics of the head can be improved without lowering the durability.

According to a sixth aspect of the present invention, in any one of the first to fourth aspects, the diaphragm includes a relatively hard hard material layer, and the beam portion is discontinuously connected to the hard material layer. An ink jet recording head is formed by providing the concave portion.

According to the sixth aspect, the strength of the diaphragm is improved, and deformation of the diaphragm due to driving of the piezoelectric element is not hindered.

According to a seventh aspect of the present invention, in the sixth aspect, the hard material layer is made of zirconium oxide, tantalum,
An ink jet recording head is selected from the group consisting of nickel and tungsten.

In the seventh aspect, the strength of the diaphragm can be reliably improved.

An eighth aspect of the present invention is the ink jet recording head according to any one of the first to fourth aspects, wherein the entire diaphragm including the beam is formed of the same material. It is in.

In the eighth aspect, for example, a beam portion is formed only on the upper portion of zirconium oxide or the like, and the piezoelectric element is patterned thereon.

According to a ninth aspect of the present invention, in any one of the first to eighth aspects, the pressure generation chamber is formed on a silicon single crystal substrate by anisotropic etching, and each layer of the piezoelectric active portion is formed. An ink jet recording head is formed by a film and a lithography method.

In the ninth aspect, an ink jet recording head having high-density nozzle openings can be manufactured in a large amount and relatively easily.

According to a tenth aspect of the present invention, there is provided an ink jet recording apparatus comprising the ink jet recording head according to any one of the first to ninth aspects.

According to the tenth aspect, there is provided an ink jet recording apparatus in which the durability of the head is improved and the reliability is improved.

[0030]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail based on embodiments.

(Embodiment 1) FIG. 1 is an exploded perspective view showing an ink jet recording head according to Embodiment 1 of the present invention, and FIG. 2 is a plan view and a cross section of one of the pressure generating chambers in the longitudinal direction. It is a figure showing a structure.

As shown in the figure, the flow path forming substrate 10 is a single crystal silicon substrate having a plane orientation of (110) in this embodiment. As the flow path forming substrate 10, usually 150 to 3
A thickness of about 00 μm is used.
Those having a thickness of about 0 to 280 μm, more preferably about 220 μm are suitable. This is because the arrangement density can be increased while maintaining the rigidity of the partition wall between the adjacent pressure generating chambers.

One surface of the flow path forming substrate 10 is an opening surface, and the other surface is formed with a 0.1 to 2 μm thick elastic film 50 made of silicon dioxide previously formed by thermal oxidation.

On the other hand, the opening surface of the flow path forming substrate 10 is anisotropically etched on a silicon single crystal substrate,
A nozzle opening 11 and a pressure generating chamber 12 are formed.

Here, in the anisotropic etching, when a silicon single crystal substrate is immersed in an alkaline solution such as KOH, it is gradually eroded, and the first (111) plane perpendicular to the (110) plane and the first (111) plane A second (1) which forms an angle of about 70 degrees with the (111) plane and forms an angle of about 35 degrees with the (110) plane.
11) plane, and the etching rate of the (111) plane is about 1/1 compared to the etching rate of the (110) plane.
This is performed using the property of being 80.
By such anisotropic etching, two first (11
Precision processing can be performed based on depth processing of a parallelogram formed by the 1) plane and two oblique second (111) planes, and the pressure generating chambers 12 can be arranged at high density. it can.

In this embodiment, the long side of each pressure generating chamber 12 is formed by the first (111) plane, and the short side is formed by the second (111) plane. The pressure generating chamber 12 is provided on the flow path forming substrate 1.
It is formed by etching until it reaches the elastic film 50 almost through 0. The amount of the elastic film 50 that is attacked by the alkaline solution for etching the silicon single crystal substrate is extremely small.

On the other hand, each nozzle opening 11 communicating with one end of each pressure generating chamber 12 is formed narrower and shallower than the pressure generating chamber 12. That is, the nozzle opening 11 is formed by partially etching (half-etching) the silicon single crystal substrate in the thickness direction. In addition,
Half etching is performed by adjusting the etching time.

Here, the size of the pressure generating chamber 12 for applying the ink droplet ejection pressure to the ink and the size of the nozzle opening 11 for ejecting the ink droplet depend on the amount of the ejected ink droplet, the ejection speed, and the ejection frequency. Optimized. For example,
When recording 360 ink droplets per inch, the nozzle openings 11 need to be formed with a groove width of several tens of μm with high accuracy.

Further, each pressure generating chamber 12 and a common ink chamber 31 described later are connected to each pressure generating chamber 1 of the sealing plate 20 described later.
The ink is supplied from a common ink chamber 31 through the ink supply communication port 21 formed at a position corresponding to one end of the pressure generation chamber 12. Distributed to

The sealing plate 20 is provided with an ink supply communication port 21 corresponding to each of the pressure generating chambers 12 and has a thickness of, for example, 0.1 to 1 mm and a coefficient of linear expansion of 300 ° C. or less. , For example, 2.5-4.5 [× 10 ⁻⁶ / ° C.]. In addition, the ink supply communication port 21
Each of the pressure generating chambers 1 is, as shown in FIGS.
It may be one slit hole 21A crossing the vicinity of the second ink supply side end or a plurality of slit holes 21B. The sealing plate 20 is provided on one side with the flow path forming substrate 10.
, And also serves as a reinforcing plate for protecting the silicon single crystal substrate from impacts and external forces. Also, sealing plate 2
0 forms one wall surface of the common ink chamber 31 on the other surface.

The common ink chamber forming substrate 30 forms the peripheral wall of the common ink chamber 31, and is formed by punching a stainless steel plate having an appropriate thickness according to the number of nozzles and the ink droplet ejection frequency. . In the present embodiment, the thickness of the common ink chamber forming substrate 30 is 0.2 mm.

The ink chamber side plate 40 is made of a stainless steel substrate, and one surface thereof constitutes one wall of the common ink chamber 31. In the ink chamber side plate 40, a thin wall 41 is formed by forming a concave portion 40a by half etching on a part of the other surface, and an ink introduction port 42 for receiving ink supply from the outside is punched and formed. ing. The thin wall 41 is for absorbing pressure generated at the time of ink droplet ejection toward the side opposite to the nozzle opening 11, and is unnecessary for the other pressure generating chambers 12 via the common ink chamber 31. Prevents positive or negative pressure from being applied.
In the present embodiment, the ink chamber side plate 40 is made 0.2 mm in consideration of rigidity required at the time of connection between the ink introduction port 42 and an external ink supply means, and a part of the thickness is 0.02 mm.
The thickness of the ink chamber side plate 40 may be 0.02 mm from the beginning in order to omit the formation of the thin wall 41 by half etching.

On the other hand, the thickness of the elastic film 50 on the side opposite to the opening surface of the flow path forming substrate 10 is, for example, about 0.5 μm.
A lower electrode film 60, a piezoelectric film 70 having a thickness of, for example, about 1 μm, and an upper electrode film 80 having a thickness of, for example, about 0.1 μm are formed by lamination in a process to be described later.
0. Here, the piezoelectric element 300 refers to a portion including the lower electrode film 60, the piezoelectric film 70, and the upper electrode film 80. Generally, one of the electrodes of the piezoelectric element 300 is used as a common electrode, and the other electrode and the piezoelectric film 70 are patterned for each pressure generating chamber 12. Here, a portion which is constituted by one of the patterned electrodes and the piezoelectric film 70 and in which a piezoelectric strain is generated by applying a voltage to both electrodes is referred to as a piezoelectric active portion 320. In the present embodiment, the lower electrode film 60 is used as a common electrode of the piezoelectric element 300, and the upper electrode film 80 is used as an individual electrode of the piezoelectric element 300. However, there is no problem even if the upper electrode film 80 is reversed for convenience of a drive circuit and wiring. In any case, the piezoelectric active portion is formed for each pressure generating chamber. Also, here
The combination of the piezoelectric element 300 and the vibration plate whose displacement is generated by driving the piezoelectric element 300 is referred to as a piezoelectric actuator. In the example described above, the elastic film 50 and the lower electrode film 6
Although 0 functions as a diaphragm, the lower electrode film may also serve as an elastic film.

In this embodiment, as will be described in detail later, a plurality of recesses 61 are provided discontinuously in portions of the lower electrode film 60 corresponding to both sides in the width direction of the piezoelectric active portion, so that a continuous beam portion is provided therebetween. The weight is set to 100 to improve the characteristics of the head by reducing the weight without lowering the strength of the diaphragm.

Here, a process for forming the piezoelectric film 70 and the like on the flow path forming substrate 10 made of a silicon single crystal substrate will be described with reference to FIG.

As shown in FIG. 4A, first, a silicon single crystal substrate wafer serving as the flow path forming substrate 10 is
Thermal oxidation is performed in a diffusion furnace at 0 ° C. to form an elastic film 50 made of silicon dioxide.

Next, as shown in FIG. 4B, a lower electrode film 60 is formed by sputtering. Pt or the like is preferable as the material of the lower electrode film 60. This is because a piezoelectric film 70 described later, which is formed by a sputtering method or a sol-gel method,
After film formation, 600 to 10 in an air atmosphere or an oxygen atmosphere
This is because it is necessary to perform crystallization by firing at a temperature of about 00 ° C. That is, the material of the lower electrode film 60 must be able to maintain conductivity at such a high temperature and in an oxidizing atmosphere. In particular, when PZT is used for the piezoelectric film 70, the conductivity of the material by diffusion of PbO is increased. It is desirable that there is little change in sex, and Pt is preferred for these reasons.

Next, as shown in FIG. 4C, a piezoelectric film 70 is formed. In this embodiment, a so-called sol in which a metal organic substance is dissolved and dispersed in a solvent is applied, dried, and gelled,
Further, the film was formed using a so-called sol-gel method in which a piezoelectric film 70 made of a metal oxide was obtained by firing at a high temperature. As a material for the piezoelectric film 70, a lead zirconate titanate (PZT) -based material is suitable when used in an ink jet recording head. The piezoelectric film 70
The film forming method is not particularly limited, and may be formed by, for example, a sputtering method.

Further, a method of forming a PZT precursor film by a sol-gel method or a sputtering method and then growing the crystal at a low temperature by a high-pressure treatment in an alkaline aqueous solution may be used.

Next, as shown in FIG. 4D, an upper electrode film 80 is formed. The upper electrode film 80 only needs to be a material having high conductivity, and many metals such as Al, Au, Ni, and Pt, and a conductive oxide can be used. In the present embodiment, P
t is formed by sputtering.

Next, as shown in FIG.
The piezoelectric film 70 and the upper electrode film 80 are patterned.

First, as shown in FIG. 5A, the lower electrode film 60, the piezoelectric film 70 and the upper electrode film 80 are etched together to pattern the entire pattern of the lower electrode film 60. Next, as shown in FIG. 5B, only the piezoelectric film 70 and the upper electrode film 80 are etched to form the piezoelectric active portion 32.
0 patterning is performed.

After patterning the piezoelectric active part 320 in this manner, as shown in FIG. 5C, the diaphragm in the region corresponding to both sides in the width direction of the piezoelectric active part 320 is formed.
In the present embodiment, a predetermined portion of the lower electrode film 60 is
Then, patterning is performed by etching until reaching a plurality of concave portions 61, and a plurality of discontinuous concave portions 61 are formed. This allows
The space between these concave portions 61 becomes a lattice-shaped beam portion 100.

The above is the film forming process. After forming the film in this manner, as shown in FIG. 5D, the silicon single crystal substrate is anisotropically etched with the above-described alkali solution to form the pressure generating chamber 12 and the like. In addition,
In the series of film formation and anisotropic etching described above, a number of chips are simultaneously formed on one wafer, and after completion of the process, each of the flow path forming substrates 10 having one chip size as shown in FIG. To divide. Further, the divided flow path forming substrate 10 is sequentially adhered and integrated with the sealing plate 20, the common ink chamber forming substrate 30, and the ink chamber side plate 40 to form an ink jet recording head.

The ink jet head of this embodiment takes in ink from the ink inlet 42 connected to external ink supply means (not shown),
After filling the inside with ink from the nozzle opening 11 to the nozzle opening 11, according to a recording signal from an external driving circuit (not shown),
By applying a voltage between the lower electrode film 60 and the upper electrode film 80 to bend and deform the elastic film 50, the lower electrode film 60 and the piezoelectric film 70, the pressure in the pressure generating chamber 12 increases and the nozzle opening 11 Ink droplets are ejected.

FIG. 6 is a plan view and a cross-sectional view showing a main part of the ink jet recording head of this embodiment.

As shown in FIGS. 6A and 6B, in the present embodiment, the piezoelectric active portion 320 including the piezoelectric film 70 and the upper electrode film 80 basically faces the pressure generating chamber 12. The piezoelectric film 70 and the upper electrode film 80 are provided in the region, and extend from one longitudinal end of the piezoelectric active portion 320 to the peripheral wall. The upper electrode film 80 is connected to an external wiring (not shown) near its end.

In the present embodiment, the lower electrode film 60 is completely removed in the thickness direction in regions corresponding to both sides in the width direction of the piezoelectric active portion 320 of the vibration plate. Are formed discontinuously in a predetermined arrangement,
Beam portions 100 formed of the lower electrode film 60 that are not removed between the concave portions 61 are formed.

As shown in FIG. 6C, such concave portions 61 have a substantially rectangular opening shape in the present embodiment, and are arranged in a grid pattern. That is, the beam portions 100 are formed in a lattice on the upper surface side of the diaphragm. This beam part 10
0 may be formed to such an extent that the diaphragm can maintain a predetermined strength in consideration of conditions such as the material of the diaphragm.

In the present embodiment, the recess 61 is formed by etching the lower electrode film 60 until the lower electrode film 60 reaches the elastic film 50. However, the present invention is not limited to this.
Further, a part of the elastic film 50 may be removed, or a part of the lower electrode film 60 in the thickness direction may be left. In any case, the depth of the concave portion 61 is preferably in the range of about 1/10 to 1/2 of the thickness of the diaphragm.

As described above, in the present embodiment, the plurality of concave portions 61 are discontinuously provided in the lower electrode film 60 constituting the diaphragm in the region opposed to both sides in the width direction of the piezoelectric active portion 320, so that the beam portion 100 is formed. Is formed, the weight of the diaphragm can be reduced without reducing the strength of the diaphragm. Therefore, it is possible to improve the characteristics of the head such as the response to the voltage application to the piezoelectric active portion 320.

In this embodiment, the opening of the recess 61 is rectangular and the beam 100 is formed in a lattice shape. However, the present invention is not limited to this. For example, as shown in FIG. The concave portion 61 may have a rhombic shape, and the beam portion 100 may be formed in an oblique lattice shape. Also, for example, FIG.
As shown in (b), the opening shape of the concave portion 61 may be circular, may be a honeycomb shape combining hexagons as shown in FIG. 7 (c), or may be a combination of other polygons. Further, a so-called truss combination in which triangles are combined as shown in FIG. In any case, a beam portion 100 having a geometric pattern is formed between the concave portions 61. As described above, the opening shape of the concave portion 61 and the pattern of the beam portion 100 are not particularly limited, but in any case, the beam portion 100 is formed substantially uniformly on the diaphragm to make the strength of the diaphragm approximately uniform. Is preferred.

In the present embodiment, the beam portion 100 is provided only in the region corresponding to both sides in the width direction of the piezoelectric active portion 320. However, the present invention is not limited to this. You may make it provide in the whole diaphragm other than the area | region which opposes.

(Embodiment 2) FIG. 8 is a plan view and a cross-sectional view of a main part of an ink jet recording head according to Embodiment 2.

In this embodiment, as shown in FIG. 8, between the elastic film 50 and the lower electrode film 60, a material harder than the lower electrode film 60, for example, zirconium oxide, tantalum,
A hard material layer 55 made of nickel, tungsten, or the like is provided. The second embodiment is the same as the first embodiment except that the lower electrode films 60 on both sides in the width direction of the piezoelectric active portion 320 are removed and the beam portions 100 are provided on the hard material layer 55.

With such a configuration, the same effect as in the first embodiment can be obtained. Further, in the present embodiment, since the beam portion 100 is formed on the hard material layer 55 that is harder than the lower electrode film 60, the strength of the diaphragm is further improved as compared with the first embodiment. Here, in the present embodiment, the diaphragm includes the elastic film 50 and the beam portion 100 of the hard material layer 55. Therefore, even if the area of the concave portion 61 is increased, the predetermined strength can be maintained, and the diaphragm can be further reduced in weight, so that the characteristics of the head can be further improved. Also, in particular, the hard material layer 65
Is formed of a material having relatively high tensile strength such as tungsten described above, the bending of the elastic film 50 due to the internal stress of the piezoelectric active portion 320 and the diaphragm is suppressed, and the vibration of the diaphragm by the driving of the piezoelectric active portion 320 is suppressed. The effect that the amount of deformation can be improved is also obtained.

In this embodiment, the hard material layer 55 is provided on the elastic film 50, and the beam portion 100 is formed of the hard material layer. However, the present invention is not limited to this.
As shown in the figure, the diaphragm is constituted only by the hard material layer 55 without providing the elastic film 50, and the beam portion 1 is provided on the hard material layer 55.
00 may be provided. As a result, the strength of the diaphragm can be further improved, the manufacturing process can be simplified, and the manufacturing cost can be reduced.

(Other Embodiments) The embodiments of the present invention have been described above, but the basic configuration of the ink jet recording head is not limited to the above.

For example, in addition to the sealing plate 20 described above, the common ink chamber forming plate 30 may be made of glass ceramic, and the thin film 41 may be made of glass ceramic as a separate member. Changes are free.

In the above-described embodiment, the nozzle openings are formed on the end surface of the flow path forming substrate 10. However, the nozzle openings may be formed to project in a direction perpendicular to the surface.

FIG. 10 is an exploded perspective view of the embodiment configured as described above, and FIG. 11 is a sectional view of the flow path. In this embodiment, the nozzle openings 11 are drilled in the nozzle substrate 120 opposite to the piezoelectric vibrator, and these nozzle openings 11
A nozzle communication port 22 for communicating the pressure generating chamber 12 with the pressure generating chamber 12 is provided so as to penetrate the sealing plate 20, the common ink chamber forming plate 30, the thin plate 41A, and the ink chamber side plate 40A.

In this embodiment, the thin plate 41
A is basically the same as the above-described embodiment except that the ink chamber side plate 40A and the ink chamber side plate 40A are separate members, and the opening is formed in the ink chamber side plate 40. Is omitted.

Here, also in this embodiment, similarly to the above-described embodiment, by providing a plurality of recesses in the diaphragm discontinuously to reduce the weight of the diaphragm, characteristics such as the responsiveness of the head are improved. be able to.

In the above embodiment, the piezoelectric layer 70
In addition, the upper electrode film 80 is extended to the peripheral wall and connected to an external wiring in the vicinity of the end. However, the present invention is not limited to this. For example, the piezoelectric layer 70 and the upper electrode film 12, and a lead electrode may be provided through a contact hole formed in the insulator layer on the upper electrode film 80.

Of course, the present invention can be similarly applied to an ink jet recording head of a type in which a common ink chamber is formed in a flow path forming substrate.

In each of the embodiments described above, a thin film type ink jet recording head which can be manufactured by applying a film forming and lithography process is described as an example.
Of course, the present invention is not limited to this. For example, a piezoelectric film is formed by laminating substrates to form a pressure generating chamber, or a piezoelectric film is formed by attaching a green sheet or by screen printing, or a piezoelectric film formed by crystal growth. The present invention can be applied to ink jet recording heads having various structures, such as those that form a recording medium.

As described above, the present invention can be applied to ink jet recording heads having various structures, as long as the gist of the present invention is not contradicted.

The ink jet recording head according to each of the embodiments constitutes a part of a recording head unit having an ink flow path communicating with an ink cartridge and the like, and is mounted on an ink jet recording apparatus. FIG.
FIG. 2 is a schematic view illustrating an example of the ink jet recording apparatus.

As shown in FIG. 12, recording head units 1A and 1B having an ink jet recording head are
Cartridges 2A and 2B constituting ink supply means are detachably provided. A carriage 3 on which the recording head units 1A and 1B are mounted is provided on a carriage shaft 5 attached to the apparatus main body 4 so as to be movable in the axial direction. I have. The recording head units 1A and 1B are, for example,
Each of them ejects a black ink composition and a color ink composition.

The driving force of the driving motor 6 is transmitted to the carriage 3 via a plurality of gears and a timing belt 7 (not shown), so that the carriage 3 on which the recording head units 1A and 1B are mounted moves along the carriage shaft 5. Moved. On the other hand, the apparatus main body 4 is provided with a platen 8 along the carriage 3. The platen 8 can be rotated by a driving force of a paper feed motor (not shown), and a recording sheet S as a recording medium such as paper fed by a paper feed roller is wound around the platen 8 and conveyed. It has become so.

[0081]

As described above, according to the present invention,
By providing a plurality of recesses discontinuously in at least the diaphragm corresponding to both sides in the width direction of the piezoelectric active portion, a reduction in the strength of the diaphragm can be suppressed, and the weight of the diaphragm can be reduced. As a result, it is possible to improve the characteristics such as the responsiveness of the head and to maintain the durability.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of an ink jet recording head according to a first embodiment of the present invention.

FIG. 2 is a plan view and a cross-sectional view of the inkjet recording head according to the first embodiment of the present invention, showing the same.

FIG. 3 is a view showing a modification of the sealing plate of FIG. 1;

FIG. 4 is a diagram showing a thin film manufacturing process according to the first embodiment of the present invention.

FIG. 5 is a diagram illustrating a thin film manufacturing process according to the first embodiment of the present invention.

FIG. 6 is a plan view and a cross-sectional view illustrating a main part of the inkjet recording head according to the first embodiment of the present invention.

FIG. 7 is a diagram schematically illustrating an example of a shape of a beam portion formed on a diaphragm.

FIG. 8 is a plan view and a cross-sectional view illustrating a main part of an ink jet recording head according to a second embodiment of the present invention.

FIG. 9 is a cross-sectional view illustrating a modified example of the ink jet recording head according to the second embodiment of the present invention.

FIG. 10 is an exploded perspective view of an ink jet recording head according to another embodiment of the present invention.

FIG. 11 is a cross-sectional view showing an ink jet recording head according to another embodiment of the present invention.

FIG. 12 is a schematic view of an ink jet recording apparatus according to an embodiment of the present invention.

[Explanation of symbols]

 Reference Signs List 10 flow path forming substrate 11 nozzle opening 12 pressure generating chamber 50 elastic film 55 hard material layer 60 lower electrode film 61 concave portion 70 piezoelectric film 80 upper electrode film 100 beam portion

Claims (10)

[Claims] 1. A flow path forming substrate in which a pressure generating chamber communicating with a nozzle opening is defined, and a pressure change is generated in the pressure generating chamber provided on one surface of the flow path forming substrate via a vibration plate. An ink jet recording head comprising a piezoelectric element to be formed, wherein at least an upper portion of the vibration plate is provided with a beam portion formed of a ridge extending in a plane direction. 2. The ink jet recording head according to claim 1, wherein the beam portion is provided at least on both sides in a width direction of the piezoelectric element in a region of the diaphragm facing the pressure generating chamber. . 3. The beam according to claim 1, wherein:
An ink jet recording head, wherein the ink jet recording head is provided over the entire upper portion of the diaphragm other than a region corresponding to the piezoelectric element. 4. The device according to claim 1, wherein the beam portion has a geometric pattern, and a region other than the beam portion is a concave portion in which at least a part in a thickness direction is removed. An ink jet recording head characterized by the following. 5. The ink jet recording head according to claim 1, wherein said diaphragm comprises an elastic film and a lower electrode, and said beam portion is formed on said lower electrode. 6. The vibration plate according to claim 1, wherein the diaphragm includes a relatively hard layer of hard material, and the beam portion is formed by providing the recess in the hard material layer discontinuously. An ink jet recording head, comprising: 7. The method according to claim 6, wherein the hard material layer comprises:
An ink jet recording head selected from the group consisting of zirconium oxide, tantalum, nickel and tungsten. 8. The ink jet recording head according to claim 1, wherein the entire diaphragm including the beam portion is formed of the same material. 9. The pressure generating chamber according to claim 1, wherein the pressure generating chamber is formed on a silicon single crystal substrate by anisotropic etching, and each layer of the piezoelectric element is formed by film formation and lithography. An ink jet recording head, comprising: 10. An ink jet recording apparatus comprising the ink jet recording head according to claim 1.