JPH0276983A - Valve device - Google Patents

Abstract

PURPOSE:To facilitate assembly and to enable accurate setting of the length of a wire by a method wherein, in a valve device employing a wire formed by a shape memory alloy, a valve main body is removably mounted to a valve casing body. CONSTITUTION:In a valve device 1, a recessed part 31 formed in a valve casing body 3 is opened upwardly, and a valve main body 2 can be removably mounted through the recessed part. Thus, the valve main body 2 can be assembled independently from the valve casing body 3, assembly of the valve main body 2 is facilitated, and the length of a wire 10 can be set accurately. Since a valve seat member 15 and a lock metal 18 are positioned by means of a valve seat engaging part 32 and a lock metal engaging part 33 of the valve casing body 3, a distance between a tip surface 11a of a valve body 11 and a valve seat 17, i.e., the opening and closing motion state of the valve body 11 is decided according to a change in the length of the wire 10.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a valve device that controls the flow of fluid such as compressed air, and particularly to a valve device that opens and closes a valve using a shape memory alloy.

[Conventional technology and its problems]

2. Description of the Related Art Electromagnetic valves using solenoids have been commonly used as valve devices for controlling the flow of fluid such as compressed air.

However, solenoid valves have a complicated structure and large mechanical parts, including a solenoid that generates an electromagnetic field and converts the generated electromagnetic field into electromagnetic force that drives the valve body, resulting in solenoid burnout and whirring. There are many problems, such as the possibility of noise generation and the need for a more complicated structure in order to proportionally control the opening of the valve body, which increases the cost.

The present applicant previously proposed a valve device capable of solving the various problems of electromagnetic valves as described above in Japanese Patent Application No. 160342/1983.

The valve device is configured so that the valve body is driven by a wire made of a shape memory alloy that expands and contracts in response to changes in temperature, and the magnitude of the current flowing through the wire made of the shape memory alloy is controlled by By controlling the length of the wire, the position of the valve body, that is, the valve opening degree, is directly controlled, which simplifies the structure of the valve device and makes it easy to configure a proportional valve. is possible.

In a valve device using a shape memory alloy wire as described above, the position of the valve body relative to the valve seat is directly determined by the wire, so the length of the wire, that is, the length of the valve body connected to both ends of the wire, It is necessary to assemble the valve device with the distance between it and the stopper fitting accurately set.

However, in the valve device disclosed in the above-mentioned prior application, since the wire passes through the valve hole formed in the main body housing, the wire and the valve body connected to the wire,
It was not easy to assemble around the wire, and it was difficult to accurately set the length of the wire when assembling the valve device. Therefore, after assembling the valve device, a mechanism for adjusting the length of the wire is provided, which makes the structure that much more complicated.

In view of the above-mentioned problems, it is an object of the present invention to provide a valve device using a wire made of a shape memory alloy, in which assembly around the wire is easy and the length of the wire can be set accurately. The purpose is

[Means to solve the problem]

In order to solve the above problems, the present invention includes a wire made of a shape memory alloy that expands and contracts depending on temperature, a valve body engaged at one end of the wire, and a stopper engaged at the other end of the wire. , a valve seat member positioned between the valve body and the stop fitting and into which the wire is inserted, a valve body, and a valve housing to which the valve body is mounted, a valve housing body; The valve housing body is formed with a recess into which the valve main body can be removably attached and through which fluid can flow, and the valve body can slide in the recess. a valve chamber into which the stopper fits to position the stopper in the axial direction; and a valve seat fitting into which the valve seat member fits and positions the valve seat member in the axial direction. It is composed of a section and a section.

[For production]

The valve main body, which consists of a wire, a valve body and stopper engaged with both ends of the wire, and a valve seat member through which the wire is inserted, is assembled separately from the valve housing, and then installed in a recess in the valve housing body. After this and other necessary measures have been taken, the lid is attached and the assembly is completed.

The recess in the valve housing body is partitioned by the valve seat member, and by seating the valve body on the valve seat member, the valve chamber and the chamber on the opposite side of the valve seat member from the valve chamber are isolated from each other. , the valve body enters the closed state.

Since the valve seat member and the stopper are positioned on the valve housing body, the distance between the valve body and the valve seat member, that is, the opening/closing state of the valve body is determined by the change in the length of the wire. By passing a current through the wire, the temperature of the wire changes, which changes the length of the wire and controls the opening/closing operation of the valve body.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is an exploded perspective view showing an embodiment of a valve device l according to the present invention, and FIG. 2 is a cross-sectional front view of the valve device l.

The valve device 1 of this embodiment functions as a normally open two-way valve.

The valve device 1 is assembled from a valve body 2, a valve housing body 3, a lid body 4, etc. that constitute a valve housing.

The valve body 2 includes a wire lO made of a shape memory alloy that expands and contracts depending on temperature, a valve body 11 connected by fitting a crimp fitting 12 crimped onto one end of the wire 10, and a wire lO crimped to the other end of the wire lO. The stopper 18, the valve body 11 and the stopper 1 are engaged with each other by the crimping fitting 19 so as not to come off.
8, a compression spring 13 through which a wire 10 is inserted;
It is composed of a washer 14 and a valve seat member 15.

The length from the tip end surface 11a of the valve body 11 to the inner end surface 18a of the stopper fitting 18 when it comes into contact with the crimp fitting 19 is set constant according to the dimensions of the recess 31 of the valve housing body 3, which will be described later. There is.

The valve seat member 15 is made of an elastic rubber material, and has a protrusion 16 that fits into a valve seat fitting portion 32, which will be described later, and a valve seat 17 provided with a valve hole 17a. The members of the valve body 2 other than the valve seat member 15 are made of a conductive material such as metal.

A recess 3I is formed in the valve housing body 3, into which the valve body 2 can be removably attached and through which fluid can flow.

The recess 31 includes a valve chamber 34 whose bottom is a circumferential surface and into which the valve body 11 can slide, a stop fitting fitting part 33 into which the stop fitting 18 is fitted and positions the stop fitting 18 in the axial direction, and a valve seat member 15. It has a valve seat fitting part 32 into which the valve seat member 15 is fitted to position the valve seat member 15 in the axial direction.

The valve seat member 15 fits tightly into the valve seat fitting portion 32, thereby partitioning the recess 31, and inserting the valve body 11 into the valve seat member 15.
By seating, the valve chamber 34 and the chamber 31a on the opposite side of the valve chamber 34 with respect to the valve seat member 15 are isolated from each other, and the valve body 11 enters a closing operation state.

The bosses 37 and 38 provided on the valve housing body 3 have a chamber 31a.
Also, the valve housing body 3 is provided with screw holes 39 for attaching screw electrodes 41, 42 for connecting a power source to the washer 14 and the stopper 18, respectively. .40. Screw holes 43, 43, . . . for attaching the lid 4 and a seal groove 44 for attaching the seal 58 are provided, respectively.

The lid body 4 has a screw 57°57 that is attached to the valve housing body 3.
. . , screw holes 51, 51 for ..., convex slope portions 52, 54 that fit into the valve chamber 34 and the chamber 31a, and a presser protrusion 55 that presses the stopper 18 that is fitted into the stopper fitting portion 33. The upper surface of the valve seat member 15 is pressed down by the flat portion 54 between the two convex plate portions 52 and 54 for sealing.

As can be understood from the above explanation, in this valve device l,
Since the recess 31 provided in the valve housing body 3 is opened upward and the valve body 2 can be detachably attached thereto, the valve body 2 can be assembled separately from the valve housing body 3. The valve main body 2 can be easily assembled, and the length of the wire 10 can be set accurately.

Since the valve seat member 15 and the stopper fitting 18 are positioned by the valve seat fitting part 32 and the stopper fitting fitting part 33 of the valve housing body 3, the tip surface 11a of the valve body 11 and the valve seat 17
The distance from the wire 10, that is, the opening/closing operation state of the valve body 11 is determined by the change in the length of the wire 10.

Therefore, next, the operation of the valve device 1 will be explained.

First, when no current flows through the wire 10, as shown in FIG. 2, the valve body 11 is biased to the left in the figure by the compression spring 13, and there is a distance between the valve body 11 and the valve seat 17. , the valve body 11 is in an open state.

Therefore, when compressed air is supplied to the port 35, the compressed air flows out from the port 36 through the chamber 31a, the valve hole 17a, and the valve chamber 34.

When a power source 61 and a switch 62 are connected between the screw electrodes 41 and 42 and the switch 62 is turned on, the screw electrodes 41 and 42 are connected. Washer 14, compression spring 13, valve body 11, crimp fitting 12, wire lO1 crimp fitting 19, stopper fitting 18, and screw electrode 42
A current flows through the circuit configured by the wire 10, and the wire 10 generates heat. As a result, the wire 10 contracts, the valve body 11 moves to the right in FIG. 2 against the compression spring 13, and the tip surface 11
a contacts the valve seat 17 with an appropriate pressure to close the valve hole 17a.

In this state, compressed air supplied from port 35 is blocked by valve body 11 and does not flow out from port 36.

That is, by passing a current through the wire 10, the wire 10
As the temperature changes, the length of the wire 10 changes and the opening/closing operation of the valve body 11 is controlled.

By using the power source 61 as a variable power source and adjusting the magnitude of the current flowing through the wire 10, the length of the wire 10 changes according to the magnitude of the current, and the opening degree of the valve body 11 is controlled proportionally. .

In the above-mentioned embodiment, a shape memory alloy single wire was used as the wire 10, but this was used as a tread wire with a steel wire, and the shape memory alloy wire was used to maintain the tension that resists the elastic force of the compression spring 13 in the normal state. The life of the shape memory alloy wire may be extended by sharing the load with the steel wire.

In the above embodiment, a shape memory alloy that contracts as the temperature rises is used as the wire 10, but by simply replacing this with one that expands as the temperature rises, a normally closed valve device can be realized. .

The embodiments described above can also be applied to on-off valves and directional control valves using needle-type, spool-type, or poppet-type valve bodies. Further, the urging means for urging the valve body 11 is not limited to the compression spring 13, and can be changed as appropriate depending on the structure of the valve device. For example, differential pressure or the weight of the valve body can be used, or a double type can be used using the same wire as the I2 ear 10. The wire 10, the valve body 11, and the stopper fitting 18 may be engaged with each other in various ways other than using the crimp fittings 12 and 19. Valve seat member 15
, the stopper 18, and the structure, shape, size, material, etc. of each part can be changed in various ways. .

〔Effect of the invention〕

According to the present invention, in a valve device using a wire made of a shape memory alloy, assembly around the wire is easy and the length of the wire can be set accurately.

Furthermore, the valve device of the present invention has a simple structure, making it easy to downsize the valve device, and reducing costs by reducing the number of parts.

[Brief explanation of the drawing]

FIG. 1 is an exploded perspective view showing an embodiment of the valve device according to the present invention, and FIG. 2 is a sectional front view of the valve device shown in FIG. 1... Valve device, 2... Valve main body, 3... Valve housing main body,
4... Lid body, 10... Wire, 11... Valve body, 1
5... Valve seat member, 18... Stop fitting, 31... Recess, 32... Valve seat fitting part, 33... Stop fitting fitting part, 34... Valve chamber.

Claims (1)

[Claims] (1) A wire made of a shape memory alloy that expands and contracts depending on temperature, a valve body engaged at one end of the wire, a stopper engaged at the other end of the wire, and the valve body and the stopper. a valve seat member located between the valve seat member and the wire inserted therethrough; and a valve housing to which the valve body is mounted, comprising: a valve housing body and a lid body; A recess into which the valve main body can be removably mounted and through which fluid can flow is formed in the housing body, and the recess has: a valve chamber into which the valve body can slide; a stop fitting fitting part into which the stop fitting is fitted to position the stop fitting in the axial direction; and a valve seat fitting part into which the valve seat member is fitted and into which the valve seat member is positioned in the axial direction. Valve device.