Valve device

Abstract

The present application provides a valve device capable of simply controlling a drive system, and even if there is a temperature change in a valve device main body, the change in flow characteristics is small. The valve device is provided with an actuator, a valve function module, and a housing. The actuator is provided with a base which is a base plate, a piezoelectric element whose one end is connected to a mounting surface of the base and extends in a first long side direction, a support member whose one end is installed on the mounting surface in parallel with the piezoelectric element and extends in a second long side direction which intersects the first long side direction, and an action part which is connected to the other end of each of the piezoelectric element and the support member and is displaced in a displacement direction which is different from both the first long side direction and the second long side direction to drive a valve part as the piezoelectric element expands and contracts. The housing is provided with a supply port which supplies fluid, a discharge port which discharges the fluid supplied from the supply port through separation of the valve part and a valve seat, and a holding part which ensures a gap between the valve function module and the housing and holds the valve function module.

Description

TECHNICAL FIELD

[0001] [RELATED APPLICATIONS]

[0002] This application claims priority to Japanese Patent Application for Utility Model No. 2020-031577 filed on February 27, 2020, entitled “Valve Device”, the disclosure of which is incorporated herein by reference in its entirety.

[0003] The present application relates to a valve device. BACKGROUND

[0004] In the past, a piezoelectric element (piezoelectric element) has existed as an element that generates a required displacement at a low voltage. The piezoelectric element is an element that has a structure in which a substance having a piezoelectric effect and a thin electrode are alternately stacked, and has a function of converting force into voltage or converting voltage into force. Since the piezoelectric element can be slightly stretched and contracted by voltage control, it is used for various fields such as a control mechanism of an inkjet mechanism of an inkjet printer, an actuator, and the like. The piezoelectric element is stretched and contracted when voltage is applied, but since the displacement generated is small, an actuator that amplifies the displacement of the piezoelectric element that is stretched and contracted and acts on an object is used.

[0005] For example, in Patent Literature 1, an actuator that can efficiently amplify and output the amount of displacement by displacing two piezoelectric elements is disclosed.

[0006] In addition, there is a technology that uses the displacement of a piezoelectric element to drive a valve portion to control contact / separation with a valve seat in a valve device that controls the passage and stop of a fluid. The valve portion driven by the piezoelectric element passes the fluid by separating from the valve seat, or stops the fluid by being in close contact with the valve seat.

[0007] For example, in Patent Literature 2, a piezoelectric valve device having a valve seat mounted on a valve body and a valve portion displaced by a piezoelectric element is disclosed. The displacement of the piezoelectric element is amplified by an actuator to drive the valve portion, and the valve portion is brought into contact / separation with the valve seat.

[0008] PRIOR ART DOCUMENTS

[0009] PATENT LITERATURE

[0010] Patent Literature 1: International Publication No. 2019 / 009035

[0011] Patent Literature 2: Japanese Patent Application Publication No. 2017-192192 SUMMARY

[0012] PROBLEMS TO BE SOLVED BY THE INVENTION

[0013] However, in the conventional actuator, since two piezoelectric elements are used, it is necessary to control the drive of each piezoelectric element, and there is a problem that it is difficult to control the drive system for obtaining a desired displacement.

[0014] In addition, the valve device main body can be disposed in various temperature environments, and the temperature of the displacement amplification function sometimes changes due to a change in the temperature of the valve device main body. Since the displacement amplification function amplifies a small displacement of the piezoelectric element, if the temperature of the displacement amplification function changes, sometimes the positional relationship or the contact pressure of the valve portion and the valve seat changes due to thermal expansion or thermal contraction of the displacement amplification function, so that the flow rate characteristics of the fluid greatly change.

[0015] Therefore, an object of the present application is to provide a valve device capable of simply controlling a drive system, and in which the change in flow rate characteristics is small even if the temperature of the valve device main body changes.

[0016] Solution to the problem

[0017] To solve the above problem, for example, the structure described in the claims is adopted. The present embodiment discloses at least the following:

[0018] (1) A valve device including: an actuator that drives a valve portion; a valve function module that has a valve seat that contacts / detaches from the valve portion; and a housing that houses the valve function module, wherein the actuator includes: a base that is a base plate; a piezoelectric element whose one end portion is attached to a mounting surface of the base and extends in a first long direction; a support member whose one end portion is attached to the mounting surface in parallel with the piezoelectric element and extends in a second long direction that intersects the first long direction; and an action portion that is connected to the other end portions of the piezoelectric element and the support member and is displaced in a displacement direction that is different from both the first long direction and the second long direction to drive the valve portion as the piezoelectric element is stretched and contracted, and the housing includes: a supply port that supplies a fluid; a discharge port that discharges the fluid supplied from the supply port through detachment of the valve portion from the valve seat; and a holding portion that secures a gap between the valve function module and the housing and holds the valve function module.

[0019] (2) In addition, in the valve device of the embodiment, the holding portion can secure the gap from the valve function module by holding a first surface of the valve function module.

[0020] (3) In addition, in the valve device of the embodiment, the holding portion can hold the valve function module by fastening the valve function module to the holding portion with a fastening member.

[0021] (4) In addition, in the valve device of the embodiment, the actuator can further include a compression member connected to each of the base and the action portion, and compressing the piezoelectric element in the first longitudinal direction.

[0022] (5) In addition, in the valve device of the embodiment, the valve device can further include a driving portion that supplies a voltage or a current to the piezoelectric element to drive the piezoelectric element to expand and contract.

[0023] (6) In addition, in the valve device of the embodiment, at least one of one end portion or the other end portion of the piezoelectric element can be connected via a connection member having a higher thermal expansion coefficient than the support member.

[0024] (7) In addition, in the valve device of the embodiment, the connection member can be formed integrally with the base.

[0025] (8) In addition, in the valve device of the embodiment, the connection member can be formed integrally with the action portion.

[0026] (9) To solve the above problem, a valve device is provided that includes a plurality of actuators that individually drive a plurality of valve portions, a valve function module that has a plurality of valve seats that individually contact and separate from the plurality of valve portions, and a housing that houses the valve function module, wherein each of the plurality of actuators includes a base that is a base plate, a piezoelectric element that has one end portion mounted to a mounting surface of the base and extends in a first longitudinal direction, a support member that has one end portion mounted to the mounting surface in parallel with the piezoelectric element and extends in a second longitudinal direction that intersects the first longitudinal direction, and an action portion that is connected to the other end portions of the piezoelectric element and the support member and displaces in a displacement direction that is different from both the first longitudinal direction and the second longitudinal direction to drive the valve portion as the piezoelectric element expands and contracts, the housing includes a supply port that supplies a fluid, a plurality of discharge ports that individually discharge the fluid supplied from the supply port through the plurality of valve portions and the valve seats that individually contact and separate, and a holding portion that secures a gap between the valve function module and the housing and holds the valve function module.

[0027] (10) In addition, in the valve device of the embodiment, the holding portion can secure the gap with the valve function module by holding a first surface of the valve function module.

[0028] (11) In addition, in the valve device of the embodiment, the holding portion can hold the valve function module by fastening the valve function module to the holding portion using a fastening member.

[0029] (12) In addition, in the valve device of the embodiment, each of the actuators can further include a compression member that is connected to each of the base and the action portion and compresses the piezoelectric element in the first longitudinal direction.

[0030] (13) In addition, in the valve device of the embodiment, a driving portion that individually supplies a voltage or a current to the piezoelectric element included in each of the actuators to individually drive the piezoelectric element to expand and contract can be further included.

[0031] (14) In addition, in the valve device of the embodiment, at least one of one end portion or the other end portion of the piezoelectric element is connected via a connection member having a higher coefficient of thermal expansion than the support member.

[0032] (15) In addition, in the valve device of the embodiment, the connection member can be formed integrally with the base.

[0033] (16) In addition, in the valve device of the embodiment, the connection member can be formed integrally with the action portion.

[0034] Effects of Invention

[0035] According to an embodiment of the present application, a valve device is provided that includes an actuator that drives a valve portion, a valve function module that has a valve seat that contacts and separates from the valve portion, and a housing that houses the valve function module. The actuator includes a base that is a base plate, a piezoelectric element that has one end portion mounted to a mounting surface of the base and extends in a first longitudinal direction, a support member that has one end portion mounted to the mounting surface in parallel with the piezoelectric element and extends in a second longitudinal direction that intersects the first longitudinal direction, and an action portion that is connected to the other end portions of the piezoelectric element and the support member and displaces in a displacement direction that is different from both the first longitudinal direction and the second longitudinal direction to drive the valve portion as the piezoelectric element expands and contracts. The housing includes a supply port that supplies a fluid, a discharge port that discharges the fluid supplied from the supply port through the separation of the valve portion from the valve seat, and a holding portion that ensures a gap between the valve function module and the housing and holds the valve function module. Thus, a valve device that can simply control a driving system and has a small change in flow characteristics even when there is a temperature change in the valve device body can be provided. BRIEF DESCRIPTION OF DRAWINGS

[0036] Figure 1 is an example of a front view of the valve device of the embodiment.

[0037] Figure 2 is an example of a side view of the valve device of the embodiment.

[0038] Figure 3is an example of a side view of the valve device of the first modification.

[0039] Figure 4 is an example of a front view of the actuator of the first embodiment.

[0040] Figure 5 is an example of a perspective view of the actuator of the first embodiment.

[0041] Figure 6 is an example of a front view of the compression member of the first embodiment.

[0042] Figure 7 is an example of a front view of the actuator of the second embodiment.

[0043] Figure 8 is an example of a front view of the compression member of the second embodiment.

[0044] Figure 9 is an example of a front view of the actuator of the third embodiment.

[0045] Figure 10 is an example of a front view of the compression member of the third embodiment.

[0046] Figure 11 is an example of a six view and a perspective view showing another modification of the actuator.

[0047] Figure 12 is an example of a six view and a perspective view in which the compression member is mounted in another modification of the actuator. DETAILED DESCRIPTION

[0048] Hereinafter, a valve device of an embodiment of the present application will be described in detail with reference to the drawings. In addition, in each drawing, the description of the same reference numeral will be omitted at times.

[0049] First, the valve device will be described using Figure 1 and Figure 2 . Figure 1 is a front view of the valve device of the embodiment.

[0050] In Figure 1 , the valve device 100 is provided with the actuator 1 of the first embodiment, the valve function module 2, and the housing 3.

[0051] The actuator 1 of the first embodiment drives the valve portion 11. The actuator 1 is provided with a base portion 12, a piezoelectric element 13, a support member 14, an acting portion 15, and a connecting member 16.

[0052] The base 12 is a portion that becomes a base disk of the actuator 1, and the actuator 1 is mounted on the valve function module 2 via the base 12. The base 12 has a mounting hole 122, and for example, a screw is passed through the mounting hole 122 and is mounted in a taphole provided on the valve function module 2 in correspondence with the mounting hole 122, whereby the actuator 1 can be mounted on the valve function module 2. The base 12 can be formed of, for example, stainless steel or the like.

[0053] As for the piezoelectric element 13, one end portion of the piezoelectric element 13 is connected to a mounting surface of the base 12. The piezoelectric element 13 is mounted to the base 12 via a mounting portion 121 formed in pair with the base 12 on the mounting surface of the base 12. The piezoelectric element 13 is formed in an elongated shape extending in the first long direction D1. As shown in FIG. 1, the piezoelectric element 13 can be formed in, for example, a cuboid. Figure 1

[0054] The piezoelectric element 13 contracts in the first long direction D1 by being supplied with a voltage or a current. As a main material constituting the piezoelectric element 13, a substance having a piezoelectric effect, that is, a piezoelectric body, such as PZT (lead zirconate titanate) can be used. The piezoelectric element 13 can also be a laminated structure in which a thin electrode and a thin piezoelectric body are alternately stacked. By being provided as such a laminated structure, a large displacement can be achieved even at a low voltage. Further, in the case where the piezoelectric element 13 is formed in a cuboid, as shown in FIG. 1, the shape is not limited to a cuboid. The piezoelectric element 13 can also be formed in a triangular prism shape or a cylindrical shape, for example. Figure 1

[0055] In the present embodiment, the piezoelectric element 13 is mounted to the base 12 via a connecting member 16. The connecting member 16 is used to compensate for the influence of thermal expansion of the piezoelectric element 13 on the actuator 1. The influence related to thermal expansion will be described later.

[0056] As for the support member 14, one end portion of the support member 14 is mounted to the mounting surface of the base 12 in parallel with the piezoelectric element 13. The support member 14 is mounted to the base 12 via the mounting portion 121. The support member 14 is formed in a cuboid extending in a direction along a second long direction D2 intersecting the first long direction D1, but the shape of the support member 14 is not limited thereto.

[0057] ​​The operation portion 15 is connected to the other end of each of the piezoelectric element 13 and the support member 14. The valve portion 11 is attached to the front end of the operation portion 15. The operation portion 15 is displaced in a displacement direction D4 different from both the first long side direction Dl and the second long side direction D2 by the expansion and contraction of the piezoelectric element 13 to drive the valve portion 11. For example, when the piezoelectric element 13 expands, the support member 14 is deformed accordingly, and thus the valve portion 11 attached to the front end of the operation portion 15 is moved in the downward direction of the drawing in the displacement direction D4. On the other hand, when the piezoelectric element 13 contracts, the support member 14 is deformed accordingly, and thus the valve portion 11 attached to the front end of the operation portion 15 is moved in the upward direction of the drawing in the displacement direction D4. The valve portion 11 attached to the front end of the operation portion 15 is moved in the displacement direction D4 by a predetermined stroke by the movement of the operation portion 15 caused by the expansion and contraction of the piezoelectric element 13. That is, the expansion and contraction of the piezoelectric element 13 in the first long side direction Dl is amplified as the stroke of the valve portion 11 in the displacement direction D4 according to the length of the operation portion 15 in the left-right direction of the drawing.

[0058] The valve portion 11 is brought into contact with and separated from the valve seat 21 formed on the valve function module 2 by moving in the displacement direction D4 by a predetermined stroke. The valve portion 11 is formed of, for example, rubber. The valve seat 21 has a contact surface corresponding to the shape of the valve portion 11. The shape of the valve seat 21 is formed, for example, by opening an exhaust hole in the flat portion of the valve function module 2. Alternatively, the shape of the valve seat 21 can be formed by providing a chimney-shaped protrusion on the valve function module 2. Further, by providing the shape of the valve seat 21 as a chimney-shaped protrusion, the contact area with the valve portion 11 is reduced, and the contact pressure can be increased. Alternatively, by providing the shape of the valve seat 21 as a chimney-shaped protrusion, the flow rate of the fluid can be stabilized, or the flow rate can be increased. By the contact and separation of the valve portion 11 and the valve seat 21, the valve function of cutting off the fluid or passing the fluid is achieved. The valve device 100 of the present embodiment illustrates an air valve when the fluid is air, but the fluid is not limited to air, and can be, for example, a liquid, a powder, a gel, or the like. Alternatively, the fluid can contain impurities such as a solid.

[0059] The valve portion 11 forms a closed state of the valve by being in contact with the valve seat 21, and is able to block the passage of air between the air pressure chamber 5 and the discharge port 24. The valve portion 11 is able to improve the blocking force of air by being in contact with the valve seat 21 at a prescribed contact pressure. On the other hand, the valve portion 11 forms an open state of the valve by being separated from the valve seat 21, and is able to allow the passage of air between the air pressure chamber 5 and the discharge port 24. Generally, a valve has a valve characteristic (flow rate characteristic) that is represented by the change in flow rate with respect to the opening of the valve. In the present embodiment, the flow rate characteristic is determined by the movement stroke of the valve portion 11 in the displacement direction D4, that is, the distance between the valve portion 11 and the valve seat 21. Therefore, the flow rate characteristic of the valve device 100 is determined by the movement of the acting portion 15 in the displacement direction D4.

[0060] The housing 3 houses the valve function module 2 in which the actuator 1 is installed. The housing 3 functions as a protective frame that protects the housed actuator 1 from dust and the like outside the valve device 100. The housing 3 has a holding portion 33. The holding portion 33 is a portion that holds the valve function module 2 and ensures the clearance 4 between the valve function module 2 and the housing 3. The holding portion 33 is in contact with the first face 22 of the valve function module 2, and holds the valve function module by being fastened to the valve function module 2 using a fastening member 331 (for example, a screw). The clearance 4 is able to increase the thermal resistance (reduce the thermal conduction) between the housing 3 and the valve function module 2, and makes it difficult for temperature changes in the housing 3 to be transmitted to the valve function module. Since the thermal resistance due to the contact between the holding portion 33 and the first face 22 is smaller (the thermal conductivity is larger) than the thermal resistance of the clearance 4, it is preferable that the contact area between the holding portion 33 and the first face 22 be small in order to reduce the thermal conduction. Therefore, the first face 22 can also use a shape (for example, a concave-convex shape or the like) that reduces the contact area. In addition, a member (heat insulating member) having a small thermal conductivity can be interposed between the holding portion 33 and the first face 22.

[0061] Since the actuator 1 moves the valve portion 11 by amplifying the expansion and contraction of the piezoelectric element 13, thermal expansion or thermal contraction due to temperature changes in each portion of the actuator can affect the movement amount of the valve portion 11, and the flow rate characteristic of the valve can change. By forming the clearance 4 between the housing 3 and the valve function module 2, the contact area between the housing 3 and the valve function module 2 is reduced, and the thermal conduction between the housing 3 and the valve function module 2 is reduced, and even if there are temperature changes in the housing 3, the temperature changes of the valve function module 2 in which the actuator 1 is installed are reduced, and it is also possible to reduce changes in the flow rate characteristic.

[0062] The first face 22 of the valve function module 2 has a discharge port 24 that discharges air that is discharged by the valve portion 11 being separated from the valve seat 21. The housing 3 has a discharge port 32 in the holding portion 33, which is opposed to the discharge port 24, to discharge the air that is discharged from the discharge port 24.

[0063] The housing 3 has a supply port 31 for supplying air. The pressure air supplied from the supply port 31 is introduced into the air pressure chamber 5 via the gap 4. The pressure air introduced into the air pressure chamber 5 is discharged from the discharge port 32 by the valve portion 11 being separated from the valve seat 21. In addition, the pressure air supplied from the supply port 31 can also form a flow path and be introduced into the air pressure chamber 5, for example, to cool the actuator 1, the piezoelectric element 13, or the support member 14.

[0064] The compression member 60 is connected to each of the base 12 and the action portion 15 and compresses the piezoelectric element 13 in the first long direction Dl. The compression member 60 can prevent damage to the piezoelectric element 13 by making it difficult to apply a load in the direction of stretching (Dl) to the piezoelectric element 13, which is easily damaged by a load in a direction other than the direction of stretching. Details of the shape of the compression member 60 will be described later.

[0065] The drive portion 70 supplies a voltage or a current to the piezoelectric element 13 and drives the piezoelectric element 13 to stretch and contract. The drive portion 70 drives the piezoelectric element 13 based on an input signal from a control device not shown, thereby being able to control the cut-off or discharge of the pressure air.

[0066] In addition, the valve device 100 can be normally closed in which the discharge of the pressure air is cut off in a state in which no voltage or the like is applied to the piezoelectric element 13, and on the other hand, can be normally open in which the pressure air is discharged in a state in which no voltage or the like is applied to the piezoelectric element 13. That is, the valve device 100 can implement both normally closed and normally open by the combination of the position of the valve portion 11 with respect to the valve seat 21 when the piezoelectric element 13 is energized and the direction of stretching of the piezoelectric element 13 when energized. The position of the valve portion 11 with respect to the valve seat 21 when not energized can be set at the time of screw fastening, for example, by increasing the size of the mounting hole 122. In addition, the direction of stretching of the piezoelectric element 13 when energized can be set by changing the polarity of the voltage or the like supplied from the drive portion 70.

[0067] Figure 2 is a side view of the valve device 100 according to the embodiment. In Figure 2 The valve device 100 has a housing 3 and a cover 35 mounted on the housing 3.

[0068] The housing 3 and the cover 35 can be made of aluminum die casting or a resin material such as PPS. The cover 35 closes the inside of the housing 3 by being mounted on the housing 3 and maintains the pressure of the introduced pressure air. For example, a rubber gasket can be interposed between the housing 3 and the cover 35.

[0069] The valve function module 2 is held to the holding portion 33 of the housing 3 on the first face 22 by the upper and lower fastening members 331. Thus, a gap 4 is created between the valve function module 2 and the housing 3. Therefore, the contact area of the housing 3 with the valve function module is reduced, the heat conduction between the housing 3 and the valve function module is reduced, the temperature change of the valve function module on which the actuator 1 is mounted is reduced even if there is a temperature change of the housing 3, and the change in the flow rate characteristic is reduced.

[0070] Next, a second modification example of the valve device 100 will be described. Figure 3 Figure 3 is a side view of the valve device of the second modification example.

[0071] The valve device 100a of the second modification example differs from the valve device 100 described in Figure 2 in that the valve function module 2a is in contact with the housing 3 on the second face 23. The valve function module 2a is in contact with the bottom of the housing 3 on both the first face 22 and the second face 23, and thus the mechanical strength can be improved, for example, the vibration of the actuator 1 with respect to vibration and the like is reduced. Further, the case where the position of the second face 23 in Figure 3 is set to the illustrated left end of the valve function module 2a is exemplified, but the position and the number of the second face 23 are arbitrary. For example, the position of the second face 23 can be set to the illustrated right end and in contact with the bottom of the housing 3. In addition, one or a plurality of second faces 23 can be set to be in contact with the housing 3 or the cover 35. Since the other portions in Figure 3 are the same as those of Figure 2 , the description thereof is omitted.

[0072] Next, the detailed description of the actuator 1 of the first embodiment described in Figure 4 and Figure 5 will be described. Figure 1 is a front view of the actuator 1 of the first embodiment. Figure 4

[0073] In Figure 4 , the acting portion 15 is displaced in the displacement direction D4 as the piezoelectric element 13 is expanded and contracted, to drive the valve portion 11 as described in Figure 1 . Thus, in the case where the piezoelectric element 13 is thermally expanded or contracted due to a temperature change, the position of the valve portion 11 or the contact pressure with the valve seat 21 is affected, and the flow rate characteristic is affected. Here, the compensation for the expansion and contraction of the piezoelectric element 13 with respect to the temperature change using the connecting member 16 will be described.

[0074] ​​The piezoelectric element 13 is attached to the base 12 via the connecting member 16. Here, the connecting member 16 is made of a material having a higher thermal expansion coefficient than the support member 14. For example, in a case where the thermal expansion coefficient of the piezoelectric element 13 is αl and the length of the first long side direction Dl is LI, the change dLl in the length at the time of temperature rise of 1°C is dLl = αl x LI. Also, in a case where the thermal expansion coefficient of the connecting member 16 is α2 and the length of the first long side direction Dl is L2, the change dL2 in the length at the time of temperature rise of 1°C is dL2 = α2 x L2, and in a case where the thermal expansion coefficient of the support member 14 is α3 and the length of the second long side direction D2 is L3, the change dL3 in the length at the time of temperature rise of 1°C is dL3 = α3 x L3.

[0075] Since the thermal expansion coefficient αl of the piezoelectric element 13 is a negative value such as -4.32 PPM / °C, the change dLl + dL2 matching the piezoelectric element 13 becomes dLl + dL2 = α2 x L2 - αl x LI (αl is a positive value). Here, by designing the parameters so that dLl + dL2 = dL3, it is possible to compensate for displacement in the displacement direction D4. For example, if dLl + dL2 = dL3 is set, α2 x L2 - αl x LI = α3 x L3. Here, if LI + L2 = L3 is set, α2 / α3 = 1 + (LI / L2) x (1 + αl / α3) > 1, α2 > α3. That is, by setting the thermal expansion coefficient α2 of the connecting member 16 to a material having a higher thermal expansion coefficient than the thermal expansion coefficient α3 of the support member 14, it is possible to compensate for the flow characteristics with respect to thermal expansion of the actuator 1.

[0076] Further, the connecting member 16 can be provided to the other end portion of the piezoelectric element 13 instead of being provided to the one end portion of the piezoelectric element 13. That is, the connecting member 16 can connect the other end portion of the piezoelectric element 13 and the acting portion 15. Also, the connecting member 16 can be provided to both the one end portion and the other end portion of the piezoelectric element 13. That is, one of the connecting members 16 can connect the one end portion of the piezoelectric element 13 and the base 12, and the other of the connecting members 16 can connect the other end portion of the piezoelectric element 13 and the acting portion 15.

[0077] Figure 5 is a perspective view of the actuator 1 of the first embodiment. In Figure 5 The actuator 1 has two compression members 60. The two compression members 60 are provided at positions sandwiching the piezoelectric element 13 and the support member 14. By using the two compression members 60, it is possible to uniformly apply a compression force to the piezoelectric element 13, and it is possible to prevent damage to the piezoelectric element 13.

[0078] The compression member 60 can prevent damage to the piezoelectric element 13 by making it difficult for the load in the tensile direction ( D1 ) to be applied to the piezoelectric element 13 , which is easily damaged by the load in the tensile direction.

[0079] Next, use Figure 6 , the compression component 60 of the first embodiment will be described in detail. Figure 6 It is a front view of the compression member 60 of the first embodiment.

[0080] exist Figure 6 In a plan view, the compression member 60 extends along a third longitudinal direction D3 that intersects the first longitudinal direction D1 and the second longitudinal direction D2. The compression member 60 includes an expandable portion 61 and a fixed portion 62 that are expandable and contractible in the third longitudinal direction D3.

[0081] The telescopic portion 61 is formed in a bellows shape extending along the third long side direction D3 and repeatedly bent in a plan view. In the example shown in the figure, the structure is bent at three locations in the third long side direction, but it is not limited to this example, and the shape can be changed arbitrarily. The telescopic portion 61 is formed in the middle part of the compression component 60 in the third long side direction D3. The fixed portion 62 is formed at both ends of the compression component 60 in the third long side direction D3. The dimension of the fixed portion 62 in the direction orthogonal to the third long side direction D3, that is, the width dimension, is formed to be larger, such as Figure 5 As shown, the base 12 and the action part 15 are respectively connected.

[0082] Next, use Figure 7 and Figure 8 , the actuator of the second embodiment is described. Figure 7 It is a front view of the actuator of the second embodiment. Figure 8 It is a front view of the compression component of the second embodiment.

[0083] The actuator 1a of the second embodiment has a different position for mounting the compression member 60B from the actuator 1 of the first embodiment. Specifically, one of the two compression members 60B extends in the first longitudinal direction D1 along the piezoelectric element 13, and the other compression member 60B extends in the second longitudinal direction D2 along the support member 14. Furthermore, the compression member 60B extending in the first longitudinal direction D1 is formed with a Figure 8 The telescopic portion 61B shown is telescopic in the first longitudinal direction D1.

[0084] Fixed portions 62B are formed at both ends of the compression member 60B in the first longitudinal direction D1. The fixed portions 62B are formed to have a larger width dimension in a direction perpendicular to the first longitudinal direction D1. Figure 8 The dimension L3 of the two fixing portions 62B in the third longitudinal direction D3 is greater than that of the fixing portions 62B formed in the embodiment shown in FIG. Figure 7The fixing slits of the action portion 15 and the base portion 12 are short in the third longitudinal direction D3.

[0085] Therefore, when the compression member 60B is fitted into the fixing slits of the action portion 15 and the base portion 12, the compression member 60B is stretched in the first longitudinal direction Dl and fitted in an elastically deformed state with a slight elongation. Thus, after the compression member 60B is fitted into the slits, the compression force from the compression member 60B can be applied to the piezoelectric element 13 via the action portion 15 and the base portion 12 by performing a recovery deformation in the third longitudinal direction D3.

[0086] Next, the actuator of the third embodiment will be described using Figure 9 and Figure 10 . Figure 9 is a front view of the actuator of the third embodiment. Figure 10 is a front view of the compression member of the third embodiment.

[0087] In the actuator lb of the third embodiment, the shape of the compression member 60C is different from that of the compression member 60 of the actuator 1 of the first embodiment. That is, the compression member 60C of the actuator lb of the third embodiment does not have a portion corresponding to the stretchable portion 61 in the actuator 1, and extends straight in the third longitudinal direction D3 as a whole. Figure 10 The two fixing portions 62 illustrated are different in the third longitudinal direction D3 from each other in the dimension L5. Figure 9 The fixing slits of the action portion 15 and the base portion 12 illustrated are different in the third longitudinal direction D3 from each other in the dimension L2.

[0088] Therefore, when the compression member 60C is fitted into the fixing slits of the action portion 15 and the base portion 12, the compression member 60C is stretched in the first longitudinal direction Dl and fitted in an elastically deformed state with a slight elongation. Thus, after the compression member 60C is fitted, the compression force from the compression member 60C can be applied to the action portion 15 and the base portion 12 by performing a recovery deformation in the third longitudinal direction D3.

[0089] In addition, as another embodiment, a hinge member that promotes deformation in the displacement direction D4 can be provided to at least one of the piezoelectric element 13 at one end portion in the first longitudinal direction Dl and the support member 14 at one end portion in the second longitudinal direction D2. Such a hinge member can also be provided to at least one of the other end portion of the piezoelectric element 13 in the first longitudinal direction Dl and the other end portion of the support member 14 in the second longitudinal direction D2.

[0090] Figure 11 is an example of six views and perspective views showing another modified example of the actuator.

[0091] In the actuator 1, it is aimed to convert the expansion and contraction deformation energy of the PZT into the energy in the displacement direction D4 of the acting portion 15 without waste as much as possible. However, in order to convert the expansion and contraction deformation of the PZT into the displacement direction D4 (up and down movement) of the acting portion 15, the PZT and the support member 14 must be deformed like bending up and down.

[0092] Although energy is required in order to perform the bending deformation, there is much waste in the energy used for the bending deformation. By forming a thin portion (hinge portion 30) in the central portion of the support member 14, the energy accompanying the bending deformation can be reduced, the up and down movement energy of the acting portion can be correspondingly increased, and the bending deformation can easily occur.

[0093] On the other hand, if the width of the hinge portion 30 is excessively reduced, the rigidity of the support member 14 is reduced, and the occurrence force of the up and down movement of the acting portion 15 is reduced. Consequently, the up and down movement energy of the acting portion 15 extracted to the output is also reduced. Therefore, the hinge width and length have an appropriate range. As one example, it is desirable to set the width of the hinge portion 30 to be about 30% or less of the thickness of the support member 14, and to set the length to be about 5% or more of the length of the support member 14. By setting to this structure, as compared with the structure without the hinge portion 30, the following effects are expected: the up and down movement amplitude of the acting portion 15 is increased by about 10% or more, and the up and down movement energy of the acting portion 15 that can be extracted is increased by about 5% or more.

[0094] In the structure of Figure 11 In the structure of

[0095] Figure 12 is an example of a six view and a perspective view of another modified example of the actuator in which a compression member is installed.

[0096] As described above, according to the actuator 1 to 1b of the present embodiment, a piezoelectric element and a support member are installed on a base portion, and an acting portion is installed on the piezoelectric element and the support member. Therefore, by displacing the piezoelectric element in the first long side direction, the acting portion can be displaced in the displacement direction. Thus, since the actuator is configured using only one piezoelectric element, as compared with the case where two piezoelectric elements are used, the driving system can be simply controlled.

[0097] In addition, since the actuator 1 to 1b is provided with the compression member, it is possible to impart a pre-compression in the compression direction to the piezoelectric element. Thus, it is possible to make it difficult to apply a load in the stretching direction to the piezoelectric element which is easily damaged by a load in the stretching direction.

[0098] The above-described embodiments should be considered in all respects as illustrative and not restrictive. The above-described embodiments can be omitted, replaced, or changed in various ways without departing from the scope and spirit of the present application.

[0099] For example, the actuator of one embodiment of the present application can be used in combination by being connected in series or in parallel. At this time, a method of connecting a plurality of actuators in series can be used, and the base portion of an actuator can be connected to the operation portion of another actuator, whereby the displacement can be further amplified. Such a method is more effective particularly in a space where the space is severely limited. In addition, a variation of the connection method in which two actuators are connected such that the angle of connection is 90° or the like can be considered.

[0100] In the above-described embodiments, a piezoelectric element is used as the expansion and contraction element, but any element having expansion and contraction function can be used without limitation, and a magnetostrictive element or a shape memory alloy or the like can be used.

[0101] Explanation of Reference Numerals

[0102] 1: actuator

[0103] 11: valve portion

[0104] 12: base portion

[0105] 121: mounting portion

[0106] 122: mounting hole

[0107] 13: piezoelectric element

[0108] 14: support member

[0109] 15: operation portion

[0110] 16: connection member

[0111] 2: valve function module

[0112] 21: valve seat

[0113] 22: first surface

[0114] 23: second surface

[0115] 24: discharge port

[0116] 3: housing

[0117] 31: supply port

[0118] 32: discharge port

[0119] 321: first discharge port

[0120] 322: second discharge port

[0121] 33: holding portion

[0122] 331: fastening member

[0123] 34: lid mounting portion

[0124] 35: lid

[0125] 4: gap

[0126] 5: air pressure chamber

[0127] 60: compression member

[0128] 61: extension portion

[0129] 62: fixed portion

[0130] 70: drive portion

[0131] 100: valve device

Claims

1. A valve device comprising: an actuator that drives the valve portion; a valve function module having a valve seat that contacts / separates from the valve portion; and A housing for receiving the valve function module, wherein: The actuator comprises: The base is the base plate; a piezoelectric element, one end of which is connected to the mounting surface of the base and extends along the first long side direction; a supporting member, one end of which is mounted on the mounting surface in parallel with the piezoelectric element and extends along a second longitudinal direction intersecting the first longitudinal direction; an action portion connected to the other end of each of the piezoelectric element and the support member, and displaced in a displacement direction different from both the first long side direction and the second long side direction as the piezoelectric element expands and contracts to drive the valve portion; and a compression member connected to each of the base portion and the action portion to compress the piezoelectric element along the first long side direction; The first long side direction and the second long side direction intersect at the action portion side, The compression member is not arranged in a space surrounded by the piezoelectric element, the support member, and the base. The housing comprises: a supply port for supplying a fluid; a discharge port that discharges the fluid supplied from the supply port by separation of the valve portion and the valve seat; and a holding portion that ensures a gap between the valve function module and the housing and holds the valve function module; A cover is installed on the housing, and the valve function module is accommodated in the housing.

2. The valve device according to claim 1, wherein The holding portion secures a gap between the holding portion and the valve function module by holding the first surface of the valve function module.

3. The valve device according to claim 1 or 2, wherein: The holding portion holds the valve function module by fastening the valve function module to the holding portion using a fastening part.

4. The valve device according to any one of claims 1 to 3, wherein: The support member of the actuator is formed integrally with the base portion and the action portion.

5. The valve device according to any one of claims 1 to 4, wherein: A driving unit is further provided for supplying a voltage or a current to the piezoelectric element to drive the piezoelectric element to expand and contract.

6. The valve device according to any one of claims 1 to 5, wherein: At least one of one end portion and the other end portion of the piezoelectric element is connected via a connection member having a higher thermal expansion coefficient than that of the support member.

7. The valve device according to any one of claims 1 to 6, wherein: A connecting member is provided to connect the one end portion of the piezoelectric element and the base portion, The connecting member is formed integrally with the base.

8. The valve device according to any one of claims 1 to 7, wherein: A second connecting member is provided to connect the other end portion of the piezoelectric element and the action portion, The second connecting member is formed integrally with the acting portion.

9. The valve device according to any one of claims 1 to 8, characterized in that The front end of the action portion is a flat surface.

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