KR100816170B1 - Actuator device, liquid jet head and liquid jet device - Google Patents

Abstract

An actuator device, a liquid ejection head, and a liquid ejection device capable of obtaining a large distortion with a small driving voltage are provided.

A piezoelectric element provided through a diaphragm provided on one side of the substrate and comprising a lower electrode, a piezoelectric layer, and an upper electrode, wherein the ratio between the piezoelectric constant d ₃₁ of the piezoelectric layer and the elastic compliance S ₁₁ ^E of the piezoelectric layer d _31. / S ₁₁ ^E is greater than ₅ ^C / m ² , and the elastic compliance S ₁₁ ^E of the diaphragm is greater than 2 x 10 ^-8 m ² / N.

Description

ACTUATOR DEVICE, LIQUID-JET HEAD AND LIQUID-JET APPARATUS}

1 is an exploded perspective view of the liquid jet head according to the first embodiment of the present invention.

2 is a plan view and a sectional view of a liquid jet head according to Embodiment 1 of the present invention.

3 is a diagram showing a relationship between distortion and stress generated in an embodiment of the present invention.

4 is a schematic perspective view of an inkjet recording apparatus according to an embodiment of the present invention.

<Description of the code>

1O Euro Forming Substrate

12 pressure generating chamber

13 communication departments

With 14 ink supply

20 nozzle plate

21 nozzle opening

30 protective board

31 reservoir

32 Piezoelectric element holding part

33 through hole

40 Compliance Board

50 elastic membrane

55 insulator film

60 lower electrode film

70 Piezoelectric Layer

80 upper electrode film

90 lead electrodes

100 reservoir

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an actuator device including a piezoelectric element and a liquid jet head and a liquid jet device including an actuator device as a drive source for injecting droplets.

An actuator device including a piezoelectric element that is displaced by applying a voltage is, for example, mounted on a liquid jet head or the like for ejecting a droplet. As a liquid ejecting apparatus having such a liquid ejecting head, for example, a plurality of pressure generating chambers for generating pressure for ejecting ink droplets by a piezoelectric element or a heating element and a common supply of ink to the respective pressure generating chambers are provided. There is an inkjet recording apparatus having a reservoir and an inkjet recording head having a nozzle opening communicating with each pressure generating chamber. In this inkjet recording apparatus, a pressure generating chamber in communication with a nozzle corresponding to a printing signal is provided. The ejection energy is applied to the ink in the ink to eject the ink droplet from the nozzle opening.

As described above, the inkjet recording head is provided with a heat generating element such as a resistance line that generates Joule heat by a drive signal in the pressure generating chamber as the pressure generating chamber, and by the bubbles generated by the heat generating element. Two types of piezoelectric vibration type which discharges ink droplets from a nozzle opening, a part of a pressure generating chamber consists of a diaphragm, deforms this diaphragm by a piezoelectric element, and discharges ink droplets from a nozzle opening. do.

In addition, two types of piezoelectric vibrating inkjet recording heads are practically used, one using a piezoelectric actuator in an axial vibration mode in which the piezoelectric element is extended and contracted in the axial direction, and one using a piezoelectric actuator in a bending vibration mode.

The former makes the cross section of the piezoelectric element abut the diaphragm to change the volume of the pressure generating chamber, thereby making it possible to manufacture a head suitable for high density printing, while matching the piezoelectric element to the arrangement pitch of the nozzle opening. There is a problem that a difficult process of separating into a bladder phase and a job of positioning and fixing the separated piezoelectric element in a pressure generating chamber are required, and the manufacturing process is complicated.

On the other hand, the latter can attach the piezoelectric element to the vibration plate by a relatively simple process of attaching the green shee of the piezoelectric material to the shape of the pressure generating chamber and firing it. Due to the use of vibration, there is a problem in that a certain area is required, and high density arrangement is difficult.

On the other hand, in order to solve the disadvantage of the latter recording head, a uniform piezoelectric material layer is formed by a film forming technique over the entire surface of the diaphragm, and the piezoelectric material layer is subjected to pressure generation by lithography. It is proposed to separate the piezoelectric element into a shape corresponding to the seal and to form the piezoelectric element so as to be independent of each pressure generating chamber (see Patent Document 1).

This eliminates the work of adhering the piezoelectric element to the diaphragm, and allows the piezoelectric element to be attached at a high density with a precise and simple method of lithography, and to reduce the thickness of the piezoelectric element. This has the advantage of being possible.

The distortion optimum condition of the piezoelectric element is that the angle θ between the polarization axis (dipole) of the piezoelectric element and the electric field is the same structure in either region of the piezoelectric body, that is, an engineered domain structure, In the rhombohedral system, the state in which the electric field E is applied in the direction of the plane direction 001 is considered to obtain the largest distortion, and the piezoelectric constants d ₃₁ and d _{33, which} are coefficients of easy distortion, The composition of the piezoelectric crystal as large as possible is improved, and a relaxor ferroelectric single crystal (PMN-P T) (see Patent Document 2), PZN-PT, and the like are known.

However, in such a ferroelectric, although d ₃₃ is more than 2500pC / N, it discovered that the maximum generated stress in the state which load is about 20MPa, but rather 35MPa of PZT is large.

[Patent Document 1] Japanese Patent Application Laid-Open No. H5-2861131

[Patent Document 2] Japanese Patent Application Laid-Open No. 2001-509312

In view of such circumstances, an object of the present invention is to provide an actuator device, a liquid jet head, and a liquid jet device that can obtain a large distortion with a small drive voltage.

Means for Solving the Invention

A first aspect of the present invention for solving the problems is arranged via a vibration plate provided on one surface of the substrate and having a piezoelectric element formed of a lower electrode, a piezoelectric layer and an upper electrode, the piezoelectric constant of the piezoelectric layer d ₃₁ And the ratio d ₃₁ / S ₁₁ ^E to the elastic compliance S ₁₁ ^E of the piezoelectric layer is greater than ₅ ^C / m ² , and the diaphragm elastic compliance S ₁₁ ^E is greater than 2 x 10 ^-8 m ² / N. Device.

In this first aspect, since the ratio d ₃₁ / S ₁₁ ^E between the piezoelectric constant d ₃₁ of the piezoelectric layer and the elastic compliance S ₁₁ ^E of the piezoelectric layer is larger than the predetermined value, and the elastic compliance of the diaphragm is larger than the predetermined value, sufficient distortion deformation Can be obtained.

According to a second aspect of the present invention, in the first aspect, the d ₃₁ / S ₁₁ ^E is larger than 7.5C / m ₂ , which is an actuator device.

In this second aspect, since the ratio d ₃₁ / S ₁₁ ^E between the piezoelectric constant d ₃₁ of the piezoelectric layer and the elastic compliance S ₁₁ ^E of the piezoelectric layer is larger than 7.5 C / m ² , sufficient distortion deformation is achieved even in a densified actuator. You can get it.

According to a third aspect of the present invention, in the first or second aspect, the piezoelectric layer is mainly composed of lead zirconate titanate (Pb (Zr, Ti) O ₃ ) and is selected from the group consisting of Y, Ce, and Nd. An actuator device characterized by mixing one kind of element as an additive.

In such a third embodiment, by mixing a predetermined element into PZT as an additive, the ratio between the piezoelectric constant d ₃₁ of the piezoelectric layer and the elastic compliance S ₁₁ ^E of the piezoelectric layer is further increased.

A 4th aspect of this invention is an actuator apparatus which contains as an additive at least 1 sort (s) of elements chosen from the group of Nb, Ta, Sb, and W in 3rd aspect.

In this fourth aspect, the desired properties can be further improved by further mixing the predetermined element into the PZT as an additive.

A fifth aspect of the present invention is the actuator device according to the third or fourth aspect, wherein the additive is contained in a total molar ratio of less than 10 at%.

In such a fifth aspect, by making the amount of the additive smaller than the predetermined value, it becomes easy to increase the ratio d ₃₁ / S ₁₁ ^E between the piezoelectric constant d ₃₁ of the piezoelectric layer and the elastic compliance S ₁₁ ^E of the piezoelectric layer.

A sixth aspect of the present invention provides pressure generating means for generating an actuator device according to any one of the first to fifth aspects to generate pressure for discharging liquid in the pressure generating chamber from a nozzle opening to a pressure generating chamber formed in the substrate. It is provided with a liquid jet head characterized in that.

In this sixth aspect, since the ratio d ₃₁ / S ₁₁ ^E between the piezoelectric constant d ₃₁ of the piezoelectric layer and the elastic compliance S ₁₁ ^E of the piezoelectric layer is larger than the predetermined value and the elastic compliance of the diaphragm is larger than the predetermined value, sufficient distortion deformation It is possible to provide a liquid jet head capable of obtaining a large distortion with a small voltage.

According to a seventh aspect of the present invention, there is provided a liquid ejection head according to the sixth aspect.

In this seventh aspect, it is possible to provide a liquid ejecting apparatus having a liquid ejecting head which significantly improves the ejection characteristics of the droplets.

Preferred Mode for Carrying Out the Invention

EMBODIMENT OF THE INVENTION Below, this invention is demonstrated in detail based on embodiment.

(Embodiment 1)

1 is an exploded perspective view showing a schematic configuration of an inkjet recording head according to Embodiment 1 of the present invention, and FIG. 2 is a plan view of FIG. 1 and a cross-sectional view taken along line A-A 'thereof.

As illustrated, the flow path forming substrate 10 is made of a silicon single crystal substrate in this embodiment, and an elastic film 50 having a thickness of 0.5 to 2 μm, which is made of silicon dioxide previously formed by thermal oxidation, is formed on both surfaces thereof. have.

In this flow path formation substrate 10, by anisotropically etching from the other surface, pressure generating chambers 12 partitioned by a plurality of firewalls 11 are provided in parallel, and the pressure generating chambers are located outside the longitudinal direction. The communication part 13 which comprises a part of the reservoir 100 which becomes a common ink chamber of 12 is formed, and is provided through the longitudinal end part of each pressure generation chamber 12, and the ink supply path 14, respectively. In communication. The ink supply passage 14 is formed to have a narrower width than the pressure generating chamber 12, and maintains a constant flow path resistance of the ink flowing from the communicating portion 13 into the pressure generating chamber 12.

Moreover, the nozzle plate 20 provided with the nozzle opening 21 which communicates with the opening surface side of the flow path formation board | substrate 10 on the opposite side to the ink supply path 14 of each pressure generation chamber 12 is provided with the adhesive agent and the heat | fever. It adhere | attaches through adhesive layers 51, such as a welding film. Further, the nozzle plate 20 has a thickness of, for example, 0.01 to 1 mm, a linear expansion coefficient of 300 ° C. or less, for example, a glass ceramic having a thickness of 2.5 to 4.5 [× 10 ⁻⁶ / ° C.], stainless steel, or the like. Consists of. The nozzle plate 20 entirely covers one surface of the flow path forming substrate 10 from one surface, and also serves as a reinforcing plate that protects the silicon single crystal substrate from impact or external force. The nozzle plate 20 may be formed of a material having substantially the same thermal expansion coefficient as the flow path formation substrate 10. In this case, since the deformation | transformation by the heat of the flow path formation board | substrate 10 and the nozzle plate 20 becomes substantially the same, it can bond easily using a thermosetting adhesive etc.

On the other hand, on the side opposite to the opening surface of the flow path forming substrate 10, as described above, an elastic film 50 having a thickness of, for example, about 1.0 μm is formed, and the elastic film 50 is formed. On the top, an insulator film 55 having a thickness of, for example, about 0.4 μm, which is made of zirconium oxide (ZrO ₂ ) or the like, is laminated. On the insulator film 55, a lower electrode film 60 having a thickness of about 0.1 to 0.5 μm made of iridium (Ir), and a thickness made of lead zirconate titanate (PZT) or the like is about 1.0 μm, for example. The piezoelectric layer 70 and a thickness of, for example, about 0.05 μm upper electrode film 80 formed of gold, platinum, iridium, or the like are laminated and formed in the process described later to form the piezoelectric element 300. . Here, the piezoelectric element 300 refers to a portion including the lower electrode film 60, the piezoelectric layer 70, and the upper electrode film 80. In general, one of the piezoelectric elements 300 is formed by patterning one electrode as a common electrode and the other electrode and the piezoelectric layer 70 for each pressure generating chamber 12. Here, the patterned portion is composed of one electrode and the piezoelectric layer 70, and the portion where piezoelectric distortion occurs due to the application of voltage to the positive electrode is called the piezoelectric active portion 320.

In the present embodiment, the lower electrode film 60 is used as the common electrode of the piezoelectric element 300 and the upper electrode film 80 is used as the individual electrode of the piezoelectric element 300. It does not interfere even if it is reversed. In either case, the piezoelectric active part 320 is formed in each pressure generation chamber 12. In addition, here, the piezoelectric element 300 and the diaphragm which a displacement generate | occur | produces by the drive of this piezoelectric element 300 are matched, and it is called an actuator apparatus. In addition, when the elastic film 50 and the insulator film 55 act as a diaphragm by the patterning of a thin film, the lower electrode film 60 which comprises the piezoelectric element 300 may also function as a diaphragm. .

Here, the piezoelectric layer 70 is a material in which the ratio d ₃₁ / S ₁₁ ^E between the piezoelectric constant d ₃₁ and the elastic compliance S ₁₁ ^E is larger than ₅ ^C / m ² , and preferably larger than 7.5 C / m ² . It is preferable. In addition, the elastic compliance S ₁₁ ^E of the diaphragm is preferably such that greater than ^{2 × 10 -8 m 2 / N} .

Thus it is that the ratio d ₃₁ / S ₁₁ ^E between the piezoelectric constant d ₃₁ and an elastic compliance S ₁₁ ^E of the piezoelectric layer 70 by more than a predetermined value, sufficient to increase the distortion deformation in the actuator device of the thin-film type, a liquid This is to ensure that a sufficient liquid discharge amount can be obtained when the injection head is used.

More specifically, in the thin film type actuator device, even if the piezoelectric constant is improved only in the related art, sufficient distortion deformation cannot be obtained, and the piezoelectric constant and elastic compliance ratio of the piezoelectric layer become important. That is, as the piezoelectric layer 70 for driving the diaphragm, the piezoelectric constant is of course somewhat large, but the present invention is completed based on the knowledge that sufficient distortion deformation cannot be obtained without a certain degree of rigidity. It became.

Of improving the piezoelectric characteristics in the case of the thin film is a point, without increasing the acoustic compliance than necessary, it is necessary to increase the d _31. For example, when additives are added at high concentrations, such as bulk materials, compliance is increased and no work is performed on the load. In the thin film, the distortion becomes a driving source, but in the bulk material, since the large voltage sensitivity of the distortion in the low voltage region becomes the driving source, the amount of the additive added as described later is completely different.

In the piezoelectric element 300 as described above, the generated stress at the time of driving is calculated by the following calculation when the voltage applied to the piezoelectric layer 70 is V and the thickness of the piezoelectric layer 70 is t _PZT . (I) become

Generated stress = (d ₃₁ / S ₁₁ ^E ) · (V / t _PZT )

Moreover, since this generated stress is E _PZT = (1 / S ₁₁ ^E ) when the elongation elastic modulus of the piezoelectric layer 70 is set to E _PZT , the generated stress is expressed by the following equation.

Generated stress = E _PZT · d ₃₁ · (V / t _PZT )

And this generated stress cannot discharge a liquid unless it is larger than the force which the distortion-deformed diaphragm tries to return. In addition, the force which a diaphragm tries to return, ie, the stress of a diaphragm, is represented by the following formula, when the elongation elastic modulus of a diaphragm is E _Sub , the thickness of a diaphragm is t _Sub , the width is W, and a displacement is delta.

Stress of diaphragm = [E _Sub · (t _Sub ) ² / W ² t _PZT ] · δ

Here, the condition that the ratio d ₃₁ / S ₁₁ ^E between the piezoelectric constant d ₃₁ and the elastic compliance S ₁₁ ^E of the piezoelectric layer 70 is larger than ₅ ^C / m ² is a condition that can obtain a bending displacement of about 300 nm. The liquid ejection head of the practical level can be obtained by the liquid ejecting head of. If it is larger than 7.5 C / m ² , the bending displacement of about 500 nm is obtained.

On the other hand, in order to this, for the same actuator device For discharging the liquid by using the liquid-jet head, the elastic compliance S ₁₁ ^E of the diaphragm is preferably greater than ^{2 × 10 -8 m 2 / N} .

In the present invention, the ratio d ₃₁ / S ₁₁ ^E of the piezoelectric constant d ₃₁ and an elastic compliance S ₁₁ ^E of the piezoelectric layer 70 is greater than 5C / m ^2, preferably from one to greater than 7.5C / m ² As the piezoelectric layer 70, lead zirconate titanate (PZT) is preferable. When PZT is used, the piezoelectric layer 70 having a sufficiently high hardness and piezoelectric constant can be realized. In addition, PMN-PT and PZN-PT, which have been developed as having a significantly large piezoelectric constant, are too soft to satisfy the above-described conditions.

Here, the additive which improves a piezoelectric constant may be mixed in PZT without remarkably reducing hardness. As such an additive, at least 1 type of element chosen from the group which consists of Y, Ce, and Nd is mentioned. Y and Ce improve the crystallization rate, improve thermal stability, and Nd aims to uniformize the composition distribution, thereby improving the piezoelectric constant.

In addition to these elements, at least one element selected from the group of Nb Ta, Sb, and W may be included as an additive. Nb prevents oxygen vacancies, Ta increases compliance, making distortion easier, Sb decreases compliance, and W increases dielectric constant to improve linearity of displacement-voltage characteristics. It is effective in combination with Y, Ce and Nd.

Such additives are preferably contained in a total molar ratio of less than 10 at%. If it is added more than that, the piezoelectric layer 70 becomes soft, that is, the elongation elastic modulus becomes small, and the above-described conditions cannot be obtained. In addition, such an additive will exist in PZT in an oxide state.

In the present invention, the piezoelectric layer 70 is formed by using such a material to form a predetermined thickness, and the piezoelectric constant and the elongation modulus are set to a predetermined value. For example, the piezoelectric layer 70 is 0.5 to 2 m. It is formed in the thickness before and after.

In addition, it is preferable that the surface orientation of the piezoelectric layer 70 is (100). In order to form such a piezoelectric layer 70, as described in the related art, a titanium layer may be formed on the lower electrode film 60 to freely grow the piezoelectric layer 70, and the lower electrode film 60 may be (100). ), The piezoelectric layer 70 may be epitaxially grown, and the piezoelectric layer 70 may be provided on the lower electrode film 60 via a base layer, and such a configuration is not particularly limited. Do not.

On the other hand, each of the upper electrode films 80, which are individual electrodes of the piezoelectric element 300, is provided from the vicinity of the end portion on the side of the ink supply passage 14 and extends to the insulator film 55, for example, gold. The lead electrode 90 made of (Au) or the like is connected.

The reservoir 100 constitutes at least part of the reservoir on the flow path formation substrate 10 on which the piezoelectric element 300 is formed, that is, on the lower electrode film 60, the insulator film 55, and the lead electrode 90. The protective substrate 30 having the portion 31 is bonded through the adhesive agent 34. In this embodiment, the reservoir part 31 penetrates through the protective substrate 30 in the thickness direction and is formed over the width direction of the pressure generating chamber 12. As described above, the reservoir formation substrate 10 The reservoir 100 which communicates with the communication part 13 and becomes a common ink chamber of each pressure generation chamber 12 is comprised.

Moreover, the piezoelectric element holding part 32 which has a space of the grade which does not inhibit the movement of the piezoelectric element 300 is provided in the area | region which opposes the piezoelectric element 300 of the protective substrate 30. As shown in FIG. The protective substrate 30 may have a space which does not impede the movement of the piezoelectric element 300, and this space may or may not be sealed.

As such a protection substrate 30, it is preferable to use the material substantially the same as the thermal expansion rate of the flow path formation board 10, for example, glass, a ceramic material, etc. In this embodiment, the flow path formation board 10 and It formed using the silicon single crystal board | substrate of the same material.

Moreover, the through hole 33 which penetrates the protective substrate 10 in the thickness direction is provided in the protective substrate 30. And the edge vicinity of the lead electrode 90 drawn out from each piezoelectric element 300 is provided so that it may expose in the through-hole 33. As shown in FIG.

Moreover, the drive circuit 110 for driving the parallel piezoelectric element 300 is fixed on the protective substrate 30. As this drive circuit 110, a circuit board, a semiconductor integrated circuit (IC), etc. can be used, for example. The drive circuit 110 and the lead electrode 90 are electrically connected to each other via a connection wiring 120 made of a conductive wire such as a bonding wire.

Moreover, the compliance board | substrate 40 which consists of the film | membrane 41 and the fixing plate 42 which seal and block is bonded on such a protection board | substrate 30. As shown in FIG. Here, the sealing film 41 is made of a material having a low rigidity of plasticity (for example, a polyphenylene sulfide (PPS) film having a thickness of 6 μm), and the sealing film ( 41) one side of the reservoir part 31 is sealed and blocked. In addition, the fixing plate 42 is formed of a hard material such as metal (for example, stainless steel (SUS) having a thickness of 30 μm). Since the area | region which faces the reservoir 100 of this fixing plate 42 becomes the opening part 43 removed completely in the thickness direction, the one surface of the reservoir 100 has the plasticity sealing sealing film 41. It is sealed with a bay.

Moreover, the ink introduction port 44 for supplying ink to the reservoir 100 is formed on the compliance board | substrate 40 of the center part outer side substantially in the longitudinal direction of this reservoir 100. As shown in FIG. The protective substrate 30 is provided with an ink introduction passage 35 communicating with the ink introduction port 44 and the side wall of the reservoir 100.

In the inkjet recording head of this embodiment as described above, ink is taken in from the ink inlet port 44 connected to an external ink supply means (not shown), and the ink is ejected from the reservoir 100 to the nozzle opening 21. After filling the inside with ink until the voltage is applied, the voltage is applied between each of the lower electrode film 60 and the upper electrode film 80 corresponding to the pressure generating chamber 12 in accordance with the recording signal from the driving circuit, thereby providing elasticity. By bending and deforming the film 50, the insulator film 55, the lower electrode film 60, and the piezoelectric layer 70, the pressure in each pressure generating chamber 12 is increased, and ink droplets are ejected from the nozzle opening 21. do.

(Example)

Ratio d ₃₁ of the piezoelectric constant d ₃₁ of the piezoelectric layer 70 and the elastic compliance S ₁₁ ^E The condition that / S ₁₁ ^E is greater than ₅ ^C / m ² is that when the electric field strength E = (V / t _pzT ) is 25 V / μm, the generated stress E _PZt · d ₃₁ · E must be greater than 12.5 MPa. On the other hand, when the displacement δ is 360 nm or more, 0.35% or more is required for distortion. The relationship between such distortion and generated stress is shown in FIG. 3 for three kinds of piezoelectric layers of PZT, Y-doped PZT (Y: 3 at% added), and PZN-PT.

As a result, in PZT and Y-PZT, although the range which can satisfy | fill the conditions of this invention is wide, it turned out that hardly the piezoelectric layer which satisfy | fills the conditions of this invention is obtained in PZN-PT.

(Example 1)

Composition _{(Pb 1 .05 Y 0 .03)} (Zr 0 .53 Ti 0 .44 X 0 .03) and a, X a Nb, Ta, Sb, at the time was changed to ^{_{W d 31 / S 11 E (}} C / m ² ). The results are shown in Table 1.

(Example 2)

Composition _{(Pb 1 .05 Ce 0 .03)} (Zr 0 .53 Ti 0 .44 X 0 .03) and a, X a Nb, Ta, Sb, at the time was changed to ^{_{W d 31 / S 11 E (}} C / m ² ). The results are shown in Table 1.

(Example 3)

Composition _{(Pb 1 .05 Ce 0 .03 Y} 0 .02) (Zr 0 .53 Ti 0 .44 X 0 .03) to, and an X (Nb + Ta), ( Nb + Sb), (Nb + W ), (Ta + Sb), was determined to ^{_{d 31 / S 11 E (C}} / m 2) at the time was changed to (Ta + W). The results are shown in Table 1.

As a result, in PZT mixed with additives, it has been found that a piezoelectric layer applicable to the present invention can be widely manufactured.

(Other embodiment)

As mentioned above, although embodiment of this invention was described, the structure of this invention is not limited to what was mentioned above.

The liquid jet head of the present invention constitutes a part of the recording head unit having an ink flow path communicating with an ink cartridge or the like, and is mounted on the liquid jet device. 4 is a schematic view showing an example of the liquid ejecting apparatus.

As shown in Fig. 4, the recording head units 1A and 1B having the liquid ejecting heads are provided with a detachable cartridge 2A and 2B constituting the ink supply means, and a carriage having the recording head units 1A and 1B mounted thereon ( 3) is freely moved in the axial direction on the carriage shaft 5 attached to the apparatus main body 4. The recording head units 1A and 1B are each for discharging the black ink composition and the color ink composition, for example.

Then, the driving force of the drive motor 6 is transmitted to the carriage 3 via a plurality of gears and timing belts 7, not shown, so that the carriage 3 on which the recording head units 1A and 1B are mounted is provided. It moves along the shuttle shaft 5. On the other hand, a platen 8 is provided along the reciprocating shaft 5 in the apparatus main body 4, and the recording sheet S, which is a recording medium such as paper fed by a paper feeding roller or the like, is played. It is to be conveyed on the tongue 8.

Here, in the above-mentioned embodiment, although the liquid jet head was demonstrated as an example of the liquid jet head of this invention, the basic structure of a liquid jet head is not limited to what was mentioned above. The present invention broadly covers the first half of a liquid jet head, and for example, various heads used in image recording apparatuses such as printers, color material jet heads used for the manufacture of color filters such as liquid crystal displays, and organic materials. The present invention can also be applied to an electrode material injection head used for forming an electrode such as an EL display, a FED (surface light emitting display), and a bioorganic injection head used for manufacturing a biochip.

Of course, the liquid ejection apparatus equipped with such a liquid ejection head is also particularly limited.

Further, the present invention can be applied not only to the actuator device mounted on the liquid jet head as a pressure generating means, but also to the actuator device mounted on all devices. For example, the actuator device can be applied to a sensor or the like in addition to the head described above.

As described above, the present invention has the effect of providing an actuator device, a liquid jet head, and a liquid jet device that can obtain a large distortion with a small driving voltage.

Claims (7)

A piezoelectric element provided through a diaphragm provided on one side of the substrate and comprising a lower electrode, a piezoelectric layer and an upper electrode, The ratio d ₃₁ / S ₁₁ ^E between the piezoelectric constant d ₃₁ of the piezoelectric layer and the elastic compliance S ₁₁ ^E of the piezoelectric layer is greater than ₅ ^C / m ² , and the elastic compliance S ₁₁ ^E of the diaphragm is 2 × 10 ^-8 m. Actuator device, characterized in that greater than ² / N. The method of claim 1, Actuator device, characterized in that d ₃₁ / S ₁₁ ^E is greater than 7.5C / m ² . The method of claim 1, The piezoelectric layer is composed of a zirconate titanate (Pb (Zr, Ti) O ₃ ) mainly and an actuator device characterized in that at least one element selected from the group consisting of Y, Ce and Nd is mixed as an additive. . The method of claim 3, wherein At least one element selected from the group of Nb, Ta, Sb, and W is contained as an additive, The actuator apparatus characterized by the above-mentioned. The method of claim 3, wherein In the case where the additive is mixed, the additive is contained less than 10 at% in the total molar ratio. The actuator device according to any one of claims 1 to 5 is provided as a pressure generating means for generating a pressure for discharging the liquid in the pressure generating chamber from the nozzle opening in the pressure generating chamber formed in the substrate. Liquid injection head. A liquid ejecting apparatus comprising the liquid ejecting head of claim 6.

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