JPH0256546B2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention is installed in a gas combustion appliance, etc., and continuously controls the outlet side gas pressure (flow rate) according to the combustion load signal, that is, the hot water temperature, room temperature, etc. The present invention relates to a proportional control type pressure control valve that enables a desired temperature to be obtained, and particularly to improving the stability of control performance of a pressure control valve with a closing function, which has a function of shutting off fluid to the pressure control valve.

Conventional technology A pressure control valve with a closing function is designed to omit a dedicated closing solenoid valve by adding a closing function to the pressure control valve to shut off fluid, thereby making the gas passage more compact and lowering costs. It is something.

A conventional pressure control valve with a closing function of this type has a valve body 1, a valve seat 2, a fluid inlet 3, and a fluid outlet 4, as shown in FIG. Further, numeral 5 is a valve body having a valve portion 6 made of an elastic member at the contact portion with the valve seat 2, and 7 is a base cap, which is attached to the valve body 1 via a sealing material 8. Reference numeral 9 denotes a spring that biases the valve body 5 in the direction of closing the valve. A diaphragm 10 that operates in response to fluid pressure is integrally provided on the upper part of the valve body 5 with a shaft 12 and a fixing member 13 together with membrane plates 11a and 11b provided above and below. Reference numeral 14 designates an electromagnetic coil 15, a yoke 16, a yoke plate 17, a sliding pipe 18, a cap 19, and a plunger 2 that is movable up and down inside the sliding pipe 18.
0, and is attached to the valve body 1 via a diaphragm bracket 21.
22 is an electric control circuit that supplies a control input signal on which a dither signal is superimposed.

In the pressure control valve with a closing function configured as described above,
When the electromagnetic coil 15 is not energized, the valve body 5 is urged in the valve closing direction by the elastic member 9, and the valve portion 6 made of an elastic body contacts the valve seat 9 to cut off the fluid.
Also, when the electromagnetic coil 15 is energized, the plunger 20
receives an electromagnetic force in the direction of opening the valve body 5, overcomes the closing force of the elastic member 9, opens the valve body 5, and lifts the valve body 5 upward by the pressure on the fluid outlet 4 side. The valve opening degree is determined by the balance between the electromagnetic force and the electromagnetic force. That is, the pressure on the fluid outlet 4 side can be controlled according to the control input signal to the electromagnetic coil 15. Then, by the dither signal superimposed on the control input signal,
This eliminates dead zones and hysteresis caused by sliding friction between the plunger 20 and the sliding pipe 18. The principle of dithering is the same principle that applies small shocks in measuring instruments and indicators to eliminate dead zones and hysteresis caused by friction, and has been known for a long time, so it is not particularly new. However, in this case, the plunger of this shock is continuously vibrated slightly using a dither signal to eliminate static friction between the plunger and the sliding pipe.

Problems to be Solved by the Invention However, with the above configuration, the plunger can be slightly vibrated by a dither signal, but the plunger and the valve body of the governor section are not fixed and only touch, so the plunger does not vibrate slightly. The slight vibration caused by the dither signal is not effectively transmitted to the sliding friction between the valve seat and the valve body, and as shown in the control characteristics of the pressure control valve with a closing function shown in Fig. 5, the vibration occurs near the valve opening position. The problem was that hysteresis occurred in the characteristics.

The present invention solves such conventional problems,
The purpose is to stabilize the control characteristics of a pressure control device with a closing function near the valve opening position.

Means for Solving the Problems In order to solve the above problems, the gas pressure control device of the present invention includes means for magnetically attracting the contact portion between one end of the electromagnetically driven plunger and the valve body of the gas governor section. The configuration is as follows.

Effects According to the present invention, a magnetic attraction force acts on the abutting portion between one end of the plunger and the valve body due to the above-described configuration.
Therefore, the plunger and the valve body are integrally coupled by magnetic attraction, and the dither signal of the plunger allows the generated micro vibrations to be directly transmitted to the valve body. Therefore, the dither effect also acts on the contact portion between the valve seat and the valve body, reducing the frictional force, making the operation around the valve open position smoother, and reducing hysteresis.

Embodiments Hereinafter, embodiments of the present invention will be described based on the accompanying drawings. In FIG. 1, the same parts as in the conventional example are indicated by the same numbers, and the valve body 1 has a valve seat 2, a fluid inlet 3, and a fluid outlet 4. Further, numeral 5 denotes a valve body having a valve portion 6 made of an elastic member at its abutting portion with the valve seat 2, and 7 a base cap, which is attached to the valve body 1 via a sealing material 8. 9 is the valve body 5
This is a spring that biases the valve in the direction of opening the valve. A diaphragm 10 that operates in response to fluid pressure is integrally provided on the upper part of the valve body 5 with membrane plates 11a and 11b provided above and below, and a shaft 12 made of a magnetic material such as electromagnetic stainless steel and a fixing member 13. . 1
4 is an electromagnetic coil 15, a yoke 16, a yoke plate 17,
Sliding pipe 18, cap 19 and sliding pipe 1
The valve body 1 is an electromagnetic force generating section consisting of a plunger 20 that is movable up and down within the valve body 8 and is attached to the valve body 1 via a diaphragm bracket 21.

22 is an electric control circuit that supplies a control input signal on which a dither signal is superimposed.

Reference numeral 23 denotes an indirect member made of a non-magnetic material fixed to the plunger 20, and a permanent magnet 24 is fixed to the side where it comes into contact with the shaft 12.
A magnetic attraction force is generated on the shaft 12, which is the abutting portion of the valve body 5. Note that the same effect can be expected even if the membrane plate 11a is made of a magnetic material.

In the above configuration, the pressure on the fluid outlet 4 side can be controlled by the same effect as in the conventional example. At this time, the shaft 12, which is integrated with the valve body 5, is always attracted to the magnet 24 due to the magnetic attraction force of the permanent magnet 24, and can be operated as if it were integrated with the plunger 20. Therefore, the slight vibration of the plunger caused by the dither signal is reliably transmitted to the valve body 5, making it possible to eliminate friction between the abutting portion of the valve body 5 and the valve seat 2, and as shown in FIG. This has the effect of reducing hysteresis caused by friction between the contact portion of the valve seat 5 and the valve body 2 near the valve, thereby providing stable control performance.

Furthermore, since the magnetic attraction force is generated using a permanent magnet, the plunger is attracted to the valve body even when the valve body is not energized, which has the effect of preventing the plunger from rattling and vibrating during transportation or handling.

Next, another embodiment of the present invention will be described with reference to FIG. The difference in FIG. 3 from the previous embodiment is that one end of the plunger is brought into direct contact with the valve body of the governor section, and as a means for magnetically attracting the contact section, the plunger is moved by electromagnetic force generated by energization of an electromagnetic coil. The structure is such that a magnetic pole of a spherical R-shaped convex portion is formed at one end, and the end surface made of a magnetic material is attracted to the abutting portion of the flat valve body. According to this structure, a permanent magnet is not used. Since the magnetic attraction is caused by electromagnetic force, the structure is simple and the purpose can be achieved without increasing costs.

In addition, since the shape of the abutting part between one end of the plunger and the valve body is formed so that the spherical R-shaped convex part and the flat surface come into contact with each other, even though the valve body is in suction with the plunger, the valve body The body can move freely, such as swinging its head, so slight changes during assembly may occur.
Even if misalignment of the axes between the plunger and the valve body occurs, smooth operation can be achieved and stable control performance can be achieved.

Effects of the Invention As described above, the gas pressure control device of the present invention provides the following effects.

(1) Since one end of the plunger and the valve body of the gas governor are brought into contact with each other directly or through an indirect member, and the abutting part is magnetically attracted by means of magnetic attraction, this occurs due to the dither signal of the control circuit. The micro-vibration of the plunger can be effectively transmitted to the valve body, reducing the friction between the contact part of the valve body and the valve seat, and eliminating the hysteresis near the opening of the control characteristic of the pressure control valve with a closing function. This has the effect of stabilizing the control characteristics.

(2) Since the friction between the contact area between the valve body and the valve seat is reduced, when the valve body is displaced to the valve closing position, the valve body can stably contact the valve seat, increasing the reliability of the closing function. It also has the effect of improving.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of a gas pressure control device according to an embodiment of the present invention, FIG. 2 is a control characteristic diagram of the same device, and FIG. 3 is a cross-sectional view of a gas pressure control device according to another embodiment of the present invention. FIG. 4 is a sectional view of a conventional gas control device, and FIG. 5 is a control characteristic diagram of FIG. 4. 1... Valve body, 2... Valve seat, 5... Valve body, 6
... Valve part, 10 ... Diaphragm, 12 ... Shaft,
14... Electromagnetic drive unit, 15... Electromagnetic coil, 16
... Yoke, 20 ... Plunger, 22 ... Control circuit.

Claims (1)

[Scope of Claims] 1. A valve body that forms a fluid passage, a diaphragm that receives the pressure of the fluid, a valve seat formed on the valve body, and a valve that faces the valve seat and is fastened to the diaphragm. an electromagnetic drive comprising: a gas governor section having a valve section made of an elastic member on either the valve body or the valve seat; a yoke; an electromagnetic coil; and a plunger movable in the axial direction of the electromagnetic coil. and a control circuit for supplying a control input signal in which a dither signal is superimposed to the electromagnetic coil, and means for magnetically attracting a contact portion between one end of the plunger and a valve body of the gas governor portion. Gas pressure control device. 2. The means for magnetic attraction is comprised of a permanent magnet fixed to the end of the joint part of the plunger and a magnetic body provided at the abutting part of the valve body.
Gas pressure control device as described in section. 3 The contact part between one end of the plunger and the valve body is a ball R.
2. The gas pressure control device according to claim 1, wherein the convex portion and the flat surface are in contact with each other.