JP2996599B2 - Multilayer piezoelectric actuator type piezoelectric element valve - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a piezoelectric element valve using a laminated piezoelectric actuator. More specifically, the present invention relates to a laminated piezoelectric actuator type piezoelectric element valve suitable for a source gas injection valve in a source gas injection facility for a nuclear fusion device, a gas control valve in pressure adjustment of a vacuum test device, and the like.

[0002]

2. Description of the Related Art Conventionally, a piezo effect (piezoelectric effect) has been used as a source gas injection valve in a source gas injection facility for a fusion device and a gas control valve in pressure adjustment of a vacuum test device.
(A) a piezoelectric element valve using a bimorph type piezoelectric element, and (b) a piezoelectric element valve such as a laminated type piezoelectric element valve using a laminated type piezoelectric element and a flow control type piezoelectric element valve are used. Have been.

FIG. 6 shows an example (a) of a bimorph type piezoelectric element valve. As shown in FIG. 6, a valve seat (32) is fixed to the center of the upper surface plate of the outlet side flange (31), and a disk-shaped bimorph type piezoelectric element is mounted on the head of the valve seat (32). A seal member (34) disposed at the center of (33) is in contact with the seal member. The bimorph type piezoelectric element (33) is placed on an insulating plate (35) and fixed by a holding plate (36).
5) is fixed to the outlet side flange (31) via the adjustment seat (37). At the center of the bimorph type piezoelectric element (33), a seal member (34) made of viton, nitrile rubber or the like is fixed by an adhesive or the like. A spring (38) is in contact with the upper surface of the seal member (34), and the lower surface of the seal member (34) is in contact with the head of the valve seat (32) due to the downward biasing force, so that gas flows out. Not sealed. By applying a DC voltage to the bimorph-type piezoelectric element (33), the displacement is concentrated near the center of the bimorph-type piezoelectric element (33), and the bimorph-type piezoelectric element (33) is directed upward against the urging force of the spring (38). By deforming the element (33) into an arc shape and separating the valve seat (32) and the sealing member (34) to form a gap between the two, gas is passed through the gap to the inlet side flange (39). The gas can be discharged from the gas introduction pipe (39a) to the gas outlet pipe (31a) of the outlet flange (31).

(B) A multi-layer piezoelectric element valve and a flow control type piezoelectric element valve using a multi-layer piezoelectric element use a sealing member by expansion and contraction of the multi-layer piezoelectric element as shown in FIG. And a lift-type multi-layer piezoelectric element valve that moves the arm to and away from the valve seat, and transmits the expansion and contraction of the multi-layer piezoelectric element to the arm as shown in FIGS. It is roughly divided into a lever-type laminated piezoelectric element valve and a flow control piezoelectric element valve which are rotated so that the seal member comes into contact with and separate from the valve seat.

In the lift type laminated piezoelectric element valve shown in FIG. 7, a valve seat (42) is fixed to a center portion of an upper surface plate of an outlet side flange (41), and a head of the valve seat (42) is provided. A seal member (45) adhered to a valve body (44) provided on the lower bracket (43). The lower bracket (43) is connected to the upper bracket (47) by connecting bolts (46) and (46), and the upper bracket (47) is a laminated piezoelectric element (48) having a large generating force.
Alternatively, two or more laminated piezoelectric elements having similar characteristics are connected in series and supported by the upper end surface, whereby the lower bracket (43) is lifted. The lower end surface of the multilayer piezoelectric element (48) is disposed on the seat (49), and the upper bracket (47)
Is urged downward by a spring (50),
The head of the valve seat (42) and the seal member (45) provided on the lower bracket (43) are in contact with each other and sealed so that gas does not flow out. The receiving seat (49) is located on the outlet flange (4).
It is fixed to the upper panel of 1). For these reasons, the structure of the valve itself is large. Then, by applying a DC voltage to the laminated piezoelectric element (48), the laminated piezoelectric element (48) is expanded against the spring (50), and the upper bracket (47), the connecting bolts (46), (46) are extended. ),
By lifting the lower bracket (43) upward and separating the sealing member (45) from the head of the valve seat (42) to form a gap between the two, gas can be passed through the gap and the inlet-side flange (51). ) Can be allowed to flow out from the gas introduction pipe part (51a) to the gas outlet pipe part (41a) of the outlet side flange (41).

In the lever type laminated piezoelectric element valve shown in FIG. 8, a valve seat (62) is fixed to the center of the upper surface plate of the outlet flange (61), and the valve seat (62) is attached to the head of the valve seat (62). Is in contact with a seal member (64) provided at the lower end of the valve body (63). The valve body (63) includes an arm (6) rotatable around a pivot pin (66) provided on a receiving seat (65).
7) is fixed to a substantially central portion by screws or the like, and
It protrudes downward through the valve body through hole of 5). The receiving seat (65) is fixed to the upper panel of the outlet flange (61). One end of the arm (67) and the lower end surface of one vertically stacked piezoelectric element (68) are connected via an element mounting plate (72) rotatable by a pin (69). The upper end of the multilayer piezoelectric element (68) has a seat (65).
Is fixed to an element mounting plate (72) provided on an element receiving seat (65) provided upright. The other end of the arm (67) is urged downward by a spring (73). Then, by applying a DC voltage to the laminated piezoelectric element (68), the laminated piezoelectric element (68) is extended, and the arm () is supported against the urging force of the spring (73) with the pivot pin (66) as a fulcrum. 67), and the sealing member (64) is rotated.
The head and the head of the valve seat (62) are separated from each other to form a gap therebetween, through which gas flows into the inlet flange (7).
4) From the gas introduction pipe part (74a) to the outlet side flange (6).
The gas can be discharged to the gas outlet pipe section (61a) of 1).

In the lever type flow control type piezoelectric element valve shown in FIG. 9, a valve seat (82) is fixed to the center of the upper surface plate of the outlet flange (81), and the head of the valve seat (82) is fixed. The seal member (84) adhered to the lower surface of the L-shaped arm (83) is in contact with. This L-shaped arm (83)
Is rotatable around a pivot pin (86) provided on a receiving seat (85) provided upright on the upper panel of the outlet flange (81). The vertical portion of the L-shaped arm (83) and one end surface of the laminated piezoelectric element (87) placed laterally are attached to an element mounting plate (8) rotatable by a pin (88).
9), and are connected via a multilayer piezoelectric element (87).
Is fixed to a U-shaped element receiving seat (90). The other end of the L-shaped arm (83) is urged downward by a spring (91). Valve seat (82)
Is provided with a pressure transducer (92). Then, by applying a DC voltage to the laminated piezoelectric element (87), the laminated piezoelectric element (87) is extended, and the L-shaped against the urging force of the spring (91) with the pivot pin (86) as a fulcrum. The mold arm (83) is rotated to separate the seal member (84) from the head of the valve seat (82) to form a gap between the two, and through this gap gas flows into the inlet side flange (93). The gas is discharged from the gas inlet pipe (93a) to the gas outlet pipe (81a) of the outlet flange (81). At this time, the flow rate is constantly monitored by a pressure transducer (92) provided laterally on the valve seat (82), and a DC voltage applied to the laminated piezoelectric element (87) is controlled so that a predetermined amount of gas flows out. be able to. Rubbers such as viton and nitrile rubber are mainly used as a seal member of the laminated piezoelectric element valve, and are fixed to a portion facing the valve seat with an adhesive or the like.

[0008]

However, the conventional bimorph-type piezoelectric element valve as shown in FIG. 6 controls the direct-current applied voltage to the bimorph-type piezoelectric element (33) as described above, so that the bimorph-type piezoelectric element (33) is controlled. The displacement is concentrated near the center of the piezoelectric element (33), and the bimorph-type piezoelectric element (33) is deformed upward in an arc shape against the urging force of the spring (38), thereby forming a valve seat (32) and a sealing member. (34)
Are separated from each other to form a gap therebetween, so that gas can be passed through the gap from the gas introduction pipe section (39a) of the inlet flange (39) to the gas outlet pipe section (31a) of the outlet flange (31). By releasing the applied voltage, the sealing member (34) is brought into contact with the head of the valve seat (32) by the urging force of the spring (38) to prevent the gas from flowing out. If the gas is flammable, the bimorph type piezoelectric element (33) may become the ignition source. Further, depending on the type, temperature, etc. of the gas used, the gas affects the characteristics of the bimorph type piezoelectric element (33), and the displacement of the bimorph type piezoelectric element (33) with respect to the applied voltage,
The generated force changes, and the gap between the head of the valve seat (32) and the seal member (34) changes due to the applied voltage,
There is a problem that the outflow becomes unstable.

In the multi-layer piezoelectric element valve shown in FIGS. 7, 8 and 9, when the gas is flammable, the displacement is caused by the residual strain of the multi-layer piezoelectric element or the shock due to the high-speed expansion and contraction of the multi-layer piezoelectric element. Then, the flammable gas may be ignited by the generated voltage at that time. Depending on the type of gas used, the temperature, etc., the gas affects the characteristics of the laminated piezoelectric element, the amount of displacement of the laminated piezoelectric element with respect to the applied voltage, the generated force, and the like change. The gap between the head and the sealing member is different from the initial one. As a result, there is a problem that the amount of outflow becomes unstable. In the multilayer piezoelectric element valve, the expansion and contraction and the generated force due to the applied voltage of the multilayer piezoelectric element are reduced by the lower bracket (4).
3) Since the power is transmitted to the arm (67) and the L-shaped arm (83) by surface contact, the contact surface with the laminated piezoelectric element becomes unstable due to a change in environment,
The expansion and contraction of the laminated piezoelectric element due to the applied voltage is caused by the valve body (44),
(63) is not transmitted uniformly and stably, and as a result, the gas flow rate becomes unstable.

The sealing member may be a valve body (44) provided on a central portion of the bimorph type piezoelectric element (33), a lower bracket (43), a valve body (63) provided on an arm (67), or , The lower surface of the L-shaped arm (83) is adhered and fixed, so that the high-speed contact or separation between the head of the valve seat and the seal member due to the deterioration of the adhesive or the high-speed expansion and contraction of the piezoelectric element, the spring The problem is that the contact position between the seal member and the head of the valve seat shifts or the seal member peels off due to the occurrence of vibration due to the high-speed response operation of the valve, and the gas seal leaks. was there.

In the laminated piezoelectric element valve, tetrafluoroethylene or polyimide resin is fixed to the lower bracket (43), arm (67), L-shaped arm (83) with a screw or the like as a seal member. However, there is a problem in that the screws and the like are easily loosened and the seal member must be replaced frequently, which makes the operation complicated. Therefore, the present invention has been made to solve the above-described drawbacks of the prior art, and changes the characteristics such as the amount of displacement and the generated force with respect to the applied voltage of the multilayer piezoelectric element due to the type of gas, temperature, and the like. It is possible to secure stable outflow of gas without disturbing, and it is possible to cut off the generated voltage even when displacement occurs due to residual strain of the multilayer piezoelectric element or shock due to high-speed expansion and contraction of the multilayer piezoelectric element. It is possible that there is no danger of igniting flammable gas, and furthermore, high-speed contact or separation between the head of the valve seat and the seal member due to high-speed expansion and contraction of the laminated piezoelectric element, and vibration of the spring due to high-speed response operation of the spring Lever type stacking with a small and simple structure that does not cause displacement of the contact position between the seal member and the head of the valve seat due to occurrence, peeling of the seal member, or occurrence of gas seal leak And its object is to provide a piezoelectric element valve.

[0012]

In order to solve the above-mentioned problems, the present invention has a pivot pin at an intermediate portion and an upper surface of an arm rotatable around the pivot pin. The working end of the laminated piezoelectric element is in contact with one of the above, and the elastic force applying means for return is in contact with the other on the upper surface side of the arm, and a seal member provided on the lower surface side of the arm The head of the valve seat is in contact with, and expands and contracts the laminated piezoelectric element by applying a voltage to the laminated piezoelectric element, and transmits this expansion and contraction to the arm via the working end of the laminated piezoelectric element, By rotating the arm with the pivot pin as a fulcrum and creating a gap between the seal member of the arm and the valve seat,
In the laminated piezoelectric element valve for allowing gas to flow out of the valve seat through the gap, a laminated piezoelectric actuator in which the laminated piezoelectric element is housed in a stretchable metal case that seals an inert gas is provided. (Claim 1).

Further, according to the present invention, in the above-mentioned piezoelectric element valve, the extendable metal case of the laminated piezoelectric actuator is a bellows, and a conical concave portion for contact with an arm is provided at the working end of the laminated piezoelectric actuator. The arm is provided with a conical convex portion that contacts the corresponding conical concave portion (Claim 2), and the seal member is disposed in the concave portion provided on the lower surface side of the arm. The seal member is fixed to the arm through a seal member holding plate provided with a hole for receiving the head of the valve seat (Claim 3). That aspect is that it is fixed at a position eccentric from the axis (claim 4).

[0014]

According to the invention as described above, the laminated piezoelectric actuator is expanded and contracted by applying a DC voltage to the laminated piezoelectric element, and the expansion and contraction is transmitted to the arm through the working end of the laminated piezoelectric actuator. By rotating the arm with the pivot pin as a fulcrum and creating a gap between the seal member of the arm and the valve seat, gas flows out of the valve seat through this gap, and application of the DC voltage is stopped. By doing so, the sealing member of the arm seals the head of the valve seat by the biasing force of the elastic force applying means for return, and the outflow of gas is stopped. At that time, since the multilayer piezoelectric element is housed in a stretchable metal case that seals an inert gas,
The laminated piezoelectric element no longer comes in direct contact with the gas,
It is possible to prevent a change in characteristics such as a displacement amount and a generated force with respect to an applied voltage of the laminated piezoelectric element due to a type of gas, a temperature, and the like.
While ensuring stable outflow of gas,
Even when displacement occurs due to residual strain of the laminated piezoelectric element or impact due to high-speed expansion and contraction of the laminated piezoelectric element, the generated voltage can be cut off. There is no danger of igniting combustible gas.

According to the second aspect of the present invention, the multilayer piezoelectric element is sealed in the inert gas by the bellows having a simple structure, and the expansion and contraction of the multilayer piezoelectric element can be performed without any trouble. According to the invention of claim 3, the seal member can be securely and firmly fixed to the arm by the seal holding plate. The contact position between the sealing member and the head of the valve seat is caused by the high-speed contact or separation between the head of the valve seat and the sealing member due to the high-speed expansion and contraction of the laminated piezoelectric element, and the occurrence of vibration due to the high-speed response operation of the spring. The sealability can be improved without displacement, peeling of the seal member, or occurrence of gas seal leak.

According to the fourth aspect of the present invention, since the valve seat is fixed at a position eccentric from the axis of the outlet flange of the upper surface plate of the outlet flange, the laminated piezoelectric actuator type piezoelectric element valve is provided. The whole can be reduced in size.

[0017]

The present invention will be described below in more detail with reference to examples. Of course, the present invention is not limited by the following examples. That is, FIG. 1 of the attached drawings is a cross-sectional view of a laminated piezoelectric actuator type piezoelectric element valve,
2 is a side view of the laminated piezoelectric actuator, FIG. 3 is a cross-sectional view of a valve seat, FIG. 4 is a side view of an arm, and FIG. 5 is a cross-sectional view of a seal member holding plate.

As exemplified in FIG. 1, the multilayered piezoelectric actuator type piezoelectric element valve (A) of the present invention has an upper surface of an outlet side flange (1) provided with a valve mechanism (B) using a multilayered piezoelectric actuator described later. The panel (1a) and the annular portion (2b) of the inlet side flange (2) having the casing portion (2a) capable of accommodating the valve mechanism are in contact with each other, and have a structure integrated by bolts and nuts. ing.

The valve mechanism (B) has a pivot pin (3) at an intermediate portion.
The working end of the laminated piezoelectric actuator (5) is brought into contact with one of the upper surfaces of the arm (4) rotatable about the pivot pin (3) as a fulcrum. A spring (6) is in contact with the other on the upper surface, and the head of a valve seat (8) is in contact with a seal member (7) provided on the lower surface of the arm (4).

The valve seat (8) is, as exemplified in FIG.
It has a tubular portion (8b) having a conical head with a gas outlet hole (8a) drilled in the axial direction, and a rectangular flange portion (8c) for easy processing and maintenance. This flange portion (8c) is placed on the upper surface plate (1a) of the outlet side flange (1) and fixed with bolts. The gas outlet hole (8a) of the valve seat is provided with a gas outlet hole (1b) drilled at a position eccentric from the axis of the outlet flange (1) of the upper panel (1a) of the outlet flange (1) by a predetermined amount. And the O-ring (1)
0), the valve seat (8) is fixed to the upper panel (1a) of the outlet side flange (1).

Further, the upper surface plate (1) of the outlet side flange (1) is provided.
A pair of support members (11) are provided upright in (a), and a block (12) having upright portions on both sides is laid on the support members (11) and fixed by bolts. A female screw hole (12a) is formed in the upper part of the block (12), into which a male screw part engraved on the lower periphery of the cover (13) for accommodating the laminated piezoelectric actuator (5) can be screwed. A pivot pin (3) of the arm (4) is erected.

The cover (13) for accommodating the laminated piezoelectric actuator (5) has a cylindrical shape, and an external thread is also engraved on the upper part of the outer periphery. The male screw at the bottom of the cover (13) is screwed into the female screw hole (12a) of the block (12), and the cover (13) is fixed to the block (12) by tightening the fixing nut (14). On the other hand, a cup-shaped adjusting nut (15) is screwed into the upper male screw, and the axial length of the laminated piezoelectric actuator (5) is adjusted by tightening the fixing nut (16). Is fixed to the cover (13). Terminal holes (15) for exposing the terminals (5a) and (5b) of the laminated piezoelectric element (5d) are provided at the top of the adjustment nut (15).
a) and (15b) are drilled. This terminal (5
(a) and (5b) are electrically connected to a current introducing terminal (not shown) provided on the outlet side flange (1) so that a DC voltage can be externally applied to the laminated piezoelectric element (5d). It has become.

As shown in FIG. 2, the laminated piezoelectric actuator (5) has a laminated piezoelectric element (5d) sealed together with an inert gas in a metal bellows (5c). The bellows (5c) can easily expand and contract in response to expansion and contraction due to application of a DC voltage to (5d). On the lower surfaces of the bellows (5c) and the multilayer piezoelectric element (5d), a conical concave portion (5) with which the conical convex portion (4a) of the arm (4) shown in FIG.
e) is provided. The terminals (5a) and (5b) of the laminated piezoelectric element (5d) protrude from the top surface of the bellows (5c), and are appropriately sealed so that the inert gas sealed in the bellows (5c) does not leak. Enclosed by means. In addition, He, Ar, Ne are used as the inert gas.
Etc. are available.

The arm (4) is rotatable by a pivot pin (3). The arm (4) is provided on the upper surface of the left arm (4) of the pivot pin (3) on the lower surface of the laminated piezoelectric actuator (5). A conical convex portion (4a) abutting the conical concave portion (5e) protrudes. Note that these concavo-convex portions are not limited to a conical shape, and may have another conical shape as long as the shape allows easy contact. Right arm (4) of pivot pin (3)
A circular concave portion (4b) with which the lower end of the spring (6) abuts is formed in the upper surface of the.

The spring (6) rotates the arm (4) clockwise by the urging force.
A spring retainer (17) is in contact with the upper end of the spring (6), and an adjusting screw (18) is attached to the spring retainer (17).
Is provided, and the biasing force can be adjusted by rotating the adjusting screw (18). The adjusting screw (18) is bored in a bridge portion of a spring holder (19) which stands on the upper surface plate (1a) of the outlet side flange (1) across the arm (4) and the valve seat (8). Female screw (1
9a).

On the other hand, a recess (4c) is provided at a position on the lower surface of the arm (4) in contact with the head of the valve seat (8), and a seal member (7) is provided in the recess (4c). ing.
The sealing member (7) is fixed to the lower surface of the arm (4) by a holding plate (20). The holding plate (20) has a rectangular shape, and a circular hole (20a) into which the head of the valve seat (8) is inserted is formed substantially in the center, and is fixed to the lower surface of the arm (4). Screw holes are drilled. As illustrated in FIG. 5, since the circular hole (20a) receives the conical head of the valve seat (8), the diameter is slightly larger than the diameter of the conical head and the sealing member (7) is not dropped. It has a diameter and is tapered so as not to hinder the contact between the head of the valve seat (8) and the sealing member (7) and the flow of gas. Since the seal member (7) can be fixed without adhering to the arm (4), an appropriate material such as rubbers such as viton and nitrile rubber, tetrafluoroethylene, and polyimide resin can be selected and used.

A connection (2c) with a gas introduction pipe (not shown) connected to the cylindrical casing part (2a) of the inlet side flange (2) is connected to a gas supply source via the gas introduction pipe. A screw hole is provided so as to be connected. A concave annular portion (1e) is engraved around the upper surface plate (1a) of the outlet side flange (1), and a retainer ring (21) and a gasket (22) are embedded in the concave annular portion (1e). ing. Then, the valve mechanism (B) is disposed on the upper surface plate (1a) of the outlet side flange (1), the annular portion (2b) of the inlet side flange (2) is combined, and the inlet side flange (2) is screwed. And the outlet side flange (1) are integrated so that the laminated piezoelectric actuator type piezoelectric element valve (A) can be assembled. Outlet flange (1)
The gas outlet pipe portion (1c) is extended from the upper surface plate (1a), and a connection portion (1d) for connecting to a gas injection pipe is provided.

Since the laminated piezoelectric actuator type piezoelectric element valve is configured as described above, the laminated piezoelectric actuator (5) is extended by the DC voltage applied to the terminals (5a) and (5b) via the current introducing terminals. This extension is transmitted to the conical convex portion (4a) of the arm (4) via the conical concave portion (5e) of the laminated piezoelectric actuator (5), and the clock of the spring (6) is pivoted about the pivot pin (3). The arm (4) is rotated counterclockwise against the urging force in the direction to create a gap between the sealing member (7) and the head of the valve seat (8), and gas is introduced into the inlet side flange. From (2), the outlet hole (8a) of the valve seat and the gas outlet hole (1) of the outlet side flange (1).
b) Outflow from the supply side to the equipment side via the gas outlet pipe section (1c). At this time, since the multi-layer piezoelectric element (5d) is sealed in the bellows (5c) together with the inert gas, the multi-layer piezoelectric element (5d) does not directly contact the gas, and depends on the type and temperature of the gas. The displacement of the laminated piezoelectric element with respect to the applied voltage, and the change in the characteristics such as the generated force can be prevented, and the displacement of the piezoelectric element and the generated force can be made constant,
While ensuring stable outflow of gas,
Even when displacement occurs due to residual strain of the laminated piezoelectric element or impact due to high-speed expansion and contraction of the laminated piezoelectric element, the generated voltage can be cut off, and there is no danger of igniting the flammable gas. Then, when the application of the DC voltage is stopped, the laminated piezoelectric actuator (5) contracts, and the arm (4) is rotated clockwise by the urging force of the spring (6), so that the head of the valve seat (8) and the arm are moved. The sealing member (7) comes into contact with the
The outflow of gas is stopped.

The gap when the gas flows out of the gap between the sealing member (7) and the head of the valve seat (8) differs depending on the leverage ratio of the laminated piezoelectric actuator (5) and the arm (4) used. However, when used as a gas injection valve or a gas control valve, the seal member (7) provided on the lower surface of the arm (4) is peeled off from the holding plate (20) because it is about several tens of micrometers (μm). It is held stably without dripping.

[0030]

Since the present invention is configured as described in detail above, it has the following effects. (I) The working end of the multilayer piezoelectric element is in contact with one of the upper surfaces of the arm having a pivot pin at an intermediate portion and rotatable about the pivot pin, and the upper end of the arm. An elastic force applying means for return is in contact with the other, and the head of the valve seat is in contact with a sealing member provided on the lower surface side of the arm. The piezoelectric element is expanded and contracted, and the expansion and contraction is transmitted to the arm through the working end of the laminated piezoelectric element, and the arm is rotated with the pivot pin as a fulcrum, so that a gap is provided between the seal member of the arm and the valve seat. In the multilayer piezoelectric element valve configured to cause the gas to flow out of the valve seat through the gap, a multilayer piezoelectric actuator in which the multilayer piezoelectric element is housed in a stretchable metal case that seals an inert gas. To provide a multilayer piezoelectric element The laminated piezoelectric actuator is expanded and contracted by applying a DC voltage, the expansion and contraction is transmitted to the arm via the working end of the laminated piezoelectric actuator, and the arm is rotated with the pivot pin as a fulcrum. By forming a gap between the arm and the seat, the gas flows out of the valve seat through the gap, and by stopping the application of the DC voltage, the energizing force of the elastic force applying means for the return is used to seal the arm. Can seal the head of the valve seat and stop outflow of gas. At this time, since the multilayer piezoelectric element is housed in a stretchable metal case that seals an inert gas, the multilayer piezoelectric element does not come into direct contact with the gas, and the gas type, temperature, etc. Characteristics of the laminated piezoelectric element against applied voltage due to applied voltage, generated force, etc. can be prevented from changing, and by stabilizing the amount of displacement and generated force of the piezoelectric element, stable gas outflow can be ensured. In addition to the above, even when displacement occurs due to residual strain of the multilayer piezoelectric element or impact due to high-speed expansion and contraction of the multilayer piezoelectric element, the generated voltage can be cut off. It is safe without igniting flammable gas.

(Ii) The expandable and contractible metal case of the laminated piezoelectric actuator is a bellows, and the working end of the laminated piezoelectric actuator is provided with a conical concave portion for contact with an arm, and the arm has a conical concave shape for contact. By providing the conical convex portion in contact with the concave portion, the multilayer piezoelectric element is sealed in an inert gas by a bellows having a simple structure, and the expansion and contraction of the multilayer piezoelectric element can be performed without any trouble.

(Iii) The seal member is provided in a concave portion provided on the lower surface side of the arm, and the seal member is attached to the arm through a seal member holding plate having a hole for receiving the head of the valve seat. By fixing, the seal member can be securely and firmly fixed to the arm by the seal holding plate, and the high-speed contact or separation between the head of the valve seat and the seal member due to the high-speed expansion and contraction of the laminated piezoelectric element. The contact position between the seal member and the head of the valve seat is shifted or the seal member peels off due to the occurrence of vibration due to the high-speed response operation of the spring, or the gas seal leak occurs. , And the sealing performance can be improved.

Also, (iv) the valve seat is fixed at a position eccentric from the axis of the outlet flange of the upper surface plate (1a) of the outlet flange, so that the valve seat can be fixed to the upper surface plate (1) of the outlet flange.
Since it can be fixed at a position eccentric from the axis of the outlet side flange of a), the whole laminated piezoelectric actuator type piezoelectric element valve can be downsized.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an example of a laminated piezoelectric actuator type piezoelectric element valve of the present invention.

FIG. 2 is a side view of the laminated piezoelectric actuator used in the laminated piezoelectric actuator type piezoelectric element valve shown in FIG.

3 is a sectional view of a valve seat of the laminated piezoelectric actuator type piezoelectric element valve shown in FIG. 1;

FIG. 4 is a side view of an arm of the laminated piezoelectric actuator type piezoelectric element valve shown in FIG. 1;

5 is a cross-sectional view of a sealing member pressing plate of the laminated piezoelectric actuator type piezoelectric element valve shown in FIG.

FIG. 6 is a sectional view showing an example of a conventional bimorph type piezoelectric element valve.

FIG. 7 is a cross-sectional view showing an example of a conventional lift-type laminated piezoelectric element valve.

FIG. 8 is a sectional view of a conventional lever-type laminated piezoelectric element valve.

FIG. 9 is a sectional view showing an example of a lever type flow control type piezoelectric element valve.

[Explanation of symbols]

 Reference Signs List A Multilayer piezoelectric actuator type piezoelectric element valve B Valve mechanism 1 Outlet flange 1a Upper panel 1b Gas outlet hole 1c Gas outlet tube portion 1d Connecting portion 1e Concave annular portion 2 Inlet flange 2a Casing portion 2b Annular portion 2c Connecting portion 3 Pivot Pin 4 Arm 4a Conical convex part 4b Circular concave part 4c Concave part 5 Multilayer piezoelectric actuator 5a, 5b Terminal 5c Bellows 5d Multilayer piezoelectric element 5e Conical concave part 6 Spring 7 Seal member 8 Valve seat 8a Gas outlet hole 8b Tubular part 8c Flange part Reference Signs List 9 retainer ring 10 O-ring 11 support member 12 block 12a female screw hole 13 cover 14 fixing nut 15 adjustment nut 15a, 15b terminal hole 17 spring retainer 18 adjustment screw 19 spring holder 19a female screw 20 retainer plate 20a square hole 21 retainer ring 22 gasket

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-4-366076 (JP, A) JP-A-1-266375 (JP, A) JP-A-61-105383 (JP, A) 109084 (JP, U) JP 2-76859 (JP, U) JP 53753 (JP, U) JP 63-141379 (JP, U) (58) Fields surveyed (Int. Cl. ⁷ , DB name) F16K 31/00-31/05 H01L 41/083

Claims (4)

(57) [Claims] An intermediate end has a pivot pin, and the working end of the laminated piezoelectric element is brought into contact with one of the upper surfaces of an arm rotatable about the pivot pin, and An elastic force applying means for return is in contact with the other side of the upper surface of the arm, and the head of the valve seat is in contact with a seal member provided on the lower surface of the arm. Is applied to expand and contract the laminated piezoelectric element, the expansion and contraction is transmitted to the arm via the working end of the laminated piezoelectric element, and the arm is rotated with the pivot pin as a fulcrum. In the laminated piezoelectric element valve in which a gas flows out of the valve seat through the gap by generating a gap between the valve and the seat, the laminated piezoelectric element is housed in a stretchable metal case that seals an inert gas. That the laminated piezoelectric actuator is provided. Characterized by a laminated piezoelectric actuator type piezoelectric element valve. 2. The expandable and contractible metal case of the laminated piezoelectric actuator is a bellows, and the working end of the laminated piezoelectric actuator is provided with a conical concave portion for contact with an arm,
2. The laminated piezoelectric actuator type piezoelectric element valve according to claim 1, wherein the arm is provided with a conical convex portion abutting on the corresponding conical concave portion. 3. A seal member is provided in a concave portion provided on the lower surface side of the arm, and the seal member is attached to the arm through a seal member holding plate having a hole for receiving a head of a valve seat. 3. The laminated piezoelectric actuator type piezoelectric element valve according to claim 1, wherein the piezoelectric element valve is fixed. 4. The multilayer piezoelectric actuator type piezoelectric element according to claim 1, wherein the valve seat is fixed at a position eccentric from an axis of the outlet flange of the upper surface plate of the outlet flange. valve.