JP2600763Y2 - Valve device - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE invention relates to a valve device for use in vacuum piping and other piping system.

[0002]

2. Description of the Related Art Conventionally, there have been manual and automatic valve devices used in vacuum piping and other piping systems.
The structure of the manual valve device usually has a structure shown in FIG. 7, and a shaft 54 having a screw 53 formed on a peripheral surface is rotatable on a valve body 52 installed opposite to a valve seat 51. And the shaft 54 is engaged with a screw hole 56 of a housing 55. By rotating the shaft 54 via an external handle 57, the valve body 52 is separated from the valve seat 51. I was in contact. On the other hand, automatic valve devices
As shown in FIG. 8, a female screw portion 58 of a shaft 54 rotatably connected to the valve body 52 and a male screw 61 connected to a drive shaft 60 of an electric motor 59 installed outside the housing 55 are engaged. With the structure or the structure in which the piston rod of the fluid pressure cylinder is connected to the shaft 54, the electric motor 5
By controlling the operation of the hydraulic cylinder 9 and the fluid pressure cylinder, the valve body 52 is moved toward and away from the valve seat 51.

A gasket 6 made of rubber or metal is provided on one of the opposing surfaces of the valve body 52 and the valve seat 51.
2, the gasket 62 is attached to the valve body 52 and the valve seat 5
1, the sealing performance is exhibited.

[0004]

In the above-described valve device, it is difficult to control the contact pressure between the sealing portion of the valve body 52 and the valve seat 51, and damage to the gasket 62 and insufficient sealing occur. There was a problem. In the manual valve device, the force for turning the handle 57 was manually adjusted, but there was an individual difference, and the contact pressure of the seal portion could not be controlled to a predetermined pressure. Therefore, by applying an excessive contact pressure, the gasket 62 may be damaged,
Insufficient sealing occurred due to too little contact pressure.
Instead of the handle 57, a shaft 5
Attempts to rotate the cylinder 4 have been known, but in a valve device used for a piping system that may be baked, the contact pressure against the gasket changes before and after baking, whereby a predetermined pressure is applied. There was a problem that contact pressure could not be obtained.

In the automatic valve device, the drive system (electric motor 59 and fluid pressure cylinder) of the valve body 52 is controlled by the position information of the valve body 52, so that the sealing portion between the valve body 52 and the valve seat 51 is provided. However, the optimum contact pressure was not always obtained. For this reason, the contact pressure becomes excessive and the gasket 62
Various problems have occurred, such as damage to the motor or overload of the electric motor 59. In FIG. 8, reference numeral 63 denotes a control device.

The present invention has been made in view of the above problems, and has as its object to provide a valve device capable of obtaining an appropriate contact pressure between a valve body and a valve seat.

[0007]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a valve device having a valve seat and a valve body opposed to the valve seat, the driving pressure for bringing the valve seat into contact with the valve body. with a position pair <br/> response to stress in the, from the flow path of the fluid
Between the drive shaft end of the valve body and the valve body
During the gasket groove receiving the contact pressure of the valve body gasket
Alternatively, a valve driving shaft and a driving force applied to the shaft
A conversion element for converting a mechanical strain generated by the shaft drive into an electric quantity is provided between the piston and the piston, and an output of the conversion element indicating the contact pressure. And / or a valve device provided to the control device of the valve body driving means.

In the above, the drive shaft for driving the valve body in the direction of moving the valve body toward and away from the valve seat is a shaft having no thread provided on its peripheral surface, and is used as a member for driving the drive shuff. Is, for example, a piston of a fluid pressure cylinder.

In the valve device as described above, an electric resistance component for converting a mechanical strain into an electric quantity, such as a semiconductor strain gauge, is used as the conversion element.

The valve drive means is an electric motor or a hydraulic cylinder.

[0011]

According to the valve device of the present invention, the contact pressure of the contact portion between the valve seat and the valve body is changed to a position where a stress corresponding to the contact pressure is generated, that is, a drive for driving the valve body. It can be grasped as the amount of mechanical strain caused by the stress in the portion where the shaft for driving and the member for driving the driving shuff are opposed, and the amount of mechanical strain can be known from the electrical signal from the conversion element. This makes it possible to accurately grasp the contact pressure at the contact portion between the valve seat and the valve element.
As a result, an appropriate contact pressure can be realized at the contact portion between the valve seat and the valve element. Therefore, problems caused by excessive contact pressure and problems caused by insufficient contact pressure can be eliminated.

[0012]

FIG. 1 shows a valve device according to a first embodiment of the present invention, in which a valve body 3 is installed opposite a valve seat 2 formed inside a housing 1. The housing 1 has connection flanges 7 and 8 provided at the distal end and the side wall of the cylinder 4 via connection pipes 5 and 6, respectively.
Is provided. Then, through the screw holes 11 of the blank flange 10 fixed to the flange 9, a shaft 12 for driving the valve body 3 formed with screw 12a on the peripheral surface is inserted, the tip of the shaft 12, the valve body 3 Is rotatably connected to the hooking piece 13. Said Sha
A semiconductor strain gauge is provided between the tip of the shaft 12 and the valve body 3.
The conversion element 14 and the spacer 15 are
Shaft 1 corresponding to the contact pressure between the valve seat 2 and the valve body 3
The contact pressure of the second 2 against the valve body 3 can be detected by the conversion element 14.
That has become way.

The conversion element 14 includes a blank flange 1
0 and the lead wire 17 installed outside the
Connected by The contact pressure display device 16 has the circuit configuration shown in FIG. In the contact pressure display device 16, the output of the conversion element 14 is given to the arithmetic circuit 18, and the output voltage of the arithmetic circuit 18 corresponding to the contact pressure is compared with the reference voltage by the comparison circuit 19, When the voltage corresponding to the voltage is higher than the reference voltage, the output of the comparison circuit 19 operates the display circuit 20. Display circuit 20
Is composed of a blinking lamp and a numerical display circuit using a liquid crystal or the like.

In FIG. 1, reference numeral 21 denotes a handle attached to the base end of the shaft 12, reference numeral 22 denotes an annular gasket mounted on a surface of the valve body 3 facing the valve seat 2, reference numeral 23 denotes an annular gasket mounted on the flange 9, and reference numeral 24 denotes Metal bellows.

In the above embodiment, when the shaft 12 is rotated through the handle 21, the valve element 3 moves as indicated by an arrow 25, comes into contact with or separates from the valve seat 2, and flows between the flanges 7 and 8. Roads can be blocked or released. When the flow path is shut off, that is, when the valve element 3 is brought into contact with and pressed against the valve seat 2, a stress equal to the contact pressure between the valve seat 2 and the valve element 3 is applied to the conversion element 14. Contact pressure display device 16
By setting a reference voltage corresponding to an appropriate contact pressure in advance, it is possible to know that an appropriate contact pressure has been reached on the display circuit 20, and the contact pressure between the valve body 3 and the valve seat 2 can be determined. Can be managed.

FIG. 3 partially shows an embodiment in which the installation portion of the conversion element 14 is changed. In FIG. 3 ,
The conversion element 1 is provided at the bottom of the annular gasket mounting groove 26 of the valve body 3.
4 is installed. Next, in FIG. 4, the conversion element 14 is installed in the annular groove 27 formed in the valve seat 2, and
The diaphragm 28 is installed so as to cover the.
In addition, the periphery of the diaphragm 28 is welded to the inner wall of the cylindrical body 4 so that no leak occurs at the time of shutoff.

Next, an example in which the present invention is applied to an automatic valve device will be described.

FIG. 5 shows an embodiment in which the valve body 3 is driven by the electric motor 29. In this embodiment, the shaft for driving the valve element 3 is the shaft 30 having no thread on the peripheral surface, and the base end of the shaft 30 is made to pass through the through hole 31 at the center of the blank flange 10. It is. A female screw 32 is formed in the proximal end portion of the shaft 30 along the axial direction.
A male screw 34 connected to a drive shaft 33 of an electric motor 29 mounted on the vehicle is engaged. The electric motor 29 is the control device 3
5 is driven and controlled by the control unit 35.
6 , the display circuit 20 in the display device shown in FIG.
6. In the figure, reference numeral 37 denotes a rotation control circuit.

In this embodiment, the electric motor 29 is rotated forward or backward through the rotation control circuit 37, so that the shaft 30 and the valve body 3 are moved as indicated by an arrow 38 to shut off the flow passage. Or it can be opened and closed. When the pressure at which the valve element 3 contacts the valve seat 2 reaches an appropriate value when the flow path is shut off, the relay circuit 36 is turned off, and the electric motor 29 can be stopped.

FIG. 7 shows an automatic embodiment using a fluid pressure cylinder. A cylinder 39 is mounted outside the blank flange 10, and a piston 40 and the valve element 3 in the cylinder 39 are connected by a shaft 41. The conversion element 14 is provided at a portion where the stress corresponding to the contact pressure between the valve seat 2 and the valve element 3 appears, and the shaft 41 and the piston 40 are opposed to each other. Is given to

In this embodiment, when the fluid (eg, oil) flowing into the chambers 43, 44 partitioned by the piston 40 of the cylinder 39 is controlled by the fluid supply / discharge control device 42,
The piston 40 and the valve element 3 move as indicated by the arrow 45,
The flow path is blocked or released. When shutting off the flow path,
When the pressure at which the valve body 3 contacts the valve seat 2 reaches an appropriate value, the fluid supply / discharge control device 42 receiving a signal from the conversion element 14
Operates to stop the supply and discharge control of the fluid, and the valve seat 2 and the valve body 3
An appropriate contact pressure is maintained at the contact portion of the motor.

[0022]

According to the present invention, the contact pressure of the contact portion between the valve seat and the valve element is changed to a position where a stress corresponding to the contact pressure is generated, that is, a driving pressure for driving the valve element. It can be grasped as the amount of mechanical strain caused by the stress at the portion where the shaft and the member for driving the driving shuff are driven, and the amount of mechanical strain can be known from the electrical signal from the conversion element. This makes it possible to accurately grasp the contact pressure at the contact portion between the valve seat and the valve element. Therefore, there is an effect that a seal failure due to an excessively small contact pressure and a gasket damage due to an excessively large contact pressure can be prevented. Further, in an automatic valve device, since there is no possibility of applying an excessive contact pressure, it is possible to prevent an overload from being applied to the electric motor and other members beforehand, so that the life of the device can be significantly extended. is there.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a manual valve device embodying the present invention.
FIG.

FIG. 2 is a block diagram of the contact pressure display device of the embodiment of FIG .

FIG. 3 is a partial sectional view of an embodiment in which the installation position of the conversion element of the present invention is changed .

FIG. 4 is a partial longitudinal sectional view of another embodiment .

FIG. 5 is a cross-sectional view of another embodiment.

FIG. 6 is a block diagram of a control device according to the embodiment of FIG . 5;

FIG. 7 is a longitudinal section of another embodiment of the automatic valve device.
FIG.

Figure 8 is a longitudinal sectional view of a conventional manual type valve device.

FIG. 9 is a longitudinal sectional view of a conventional automatic valve device.

[Explanation of symbols]

 2 Valve seat 3 Valve 12 Shaft 14 Conversion element 16 Contact pressure display device 22 Annular gasket 29 Electric motor 30 Shaft 35 Control device 39 Cylinder 40 Piston 42 Fluid supply / discharge control device

Claims (1)

(57) [Scope of request for utility model registration] In a valve device having a valve seat and a valve body opposed to the valve seat, a driving pressure for bringing the valve seat into contact with the valve body is provided.
The position where the stress corresponding to the force occurs and the fluid flow
Drive shaft end and valve of valve body in position to isolate from road
Gasket that receives the contact pressure of the valve body gasket
A shaft for driving the valve body or the valve body, and a driving force applied to the shaft
Generated by shaft drive between the piston and
A conversion element for converting the amount of mechanical strain into an electric quantity is provided, and the output of the conversion element is provided to a control unit for displaying the contact pressure and / or a valve driving unit. A valve device characterized by the following.