JPH04327079A - Selector valve - Google Patents

Abstract

PURPOSE:To reduce an impact sound by opening a valve by constituting an elastic body in the pressure chamber of a switching diaphragm in a selector valve to have non-linear elastic characteristic such that its elastic coefficient is greater after the opening of the switching diaphragm than in the opening initial stage. CONSTITUTION:A selector valve 1 has a first switching diaphragm 8 for opening and closing a valve hole 6 between an input passage 3 and a first output passage 4 and a second switching diaphragm 18 for opening and closing a valve hole 16 by the internal pressure of a pressure chamber 20 and the pressing force of elastic bodies 24, 25 in the pressure chamber 20 between the input passage 3 and a second output passage 5. The pressure of the first output passage 4 is introduced to the pressure chamber 20 by a back pressure guide passage 19. An inner spring offset regulating screw 22 is provided on a communicating hole 27 different from the back pressure guide passage 19, and an outer spring 24 having weak spring force is disposed between the second switching diaphragm 18 and an upper wall 23. An inner spring 25 having strong spring force and a free end on a taper part 22-2 side is disposed between the second switching diaphragm 18 and the taper part 22-2 of the.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a switching valve for switching a fluid flow path.

0002

2. Description of the Related Art FIG. 2 shows a longitudinal sectional view of a conventionally used switching valve. The switching valve 101 has an input flow path 3 formed on one side of the casing 2, and a first output flow path 4 and a second output flow path 5 are formed in parallel with each other at intervals in a direction perpendicular to the input flow path 3. ing. The input channel 3 and the first
A first valve hole 6 is formed between the output passage 4 and the first valve hole 6, and a valve seat 7 is formed around the upper opening of the first valve hole 6. A first switching diaphragm 8 that opens and closes the first valve hole 6 is disposed on the valve seat 7 so as to be able to come into and out of it. The outer peripheral portion of the first switching diaphragm 8 is held between the casing 2 and a case 9 fitted in a recess 2a on the casing 2.

A solenoid 10 is disposed on the case 9, and a bobbin 12 around which a coil 11 of the solenoid 10 is wound.
A guide sleeve 13 integral with the case 9 is inserted inside. The guide sleeve 13 includes a plunger 15 that urges the first switching diaphragm 8 downward with a spring 14.
is stored. The input channel 3 and the second
A second valve hole 16 is formed between the output flow path 5 and the second output flow path 5 in a direction perpendicular to the second output flow path 5, and a valve seat 17 is formed around the left end opening of the second valve hole 16. There is. This valve seat 17
A second switching diaphragm 18 that opens and closes the second valve hole 16 is disposed in a manner that it can be moved toward and away from the second valve hole 16 .

A pressure chamber 20 is formed on the left side of the second switching diaphragm 18 facing the second valve hole 16 and communicates with the first output flow path 4 via a back pressure guide path 19. The pressure introduced from the passage 4 drives the second switching diaphragm 18 to open and close the second valve hole 16. Further, a spring 21, which is an elastic body, is provided in the pressure chamber 20 to press the second switching diaphragm 18 against the second valve hole 16 to close it. In this configuration, when the solenoid 10 is not energized, the plunger 15 is urged by the pressing force of the spring 14, the first switching diaphragm 8 is pressed against the first valve hole 6, the first valve hole 6 is closed, and the first valve hole 6 is closed. No fluid flows through the output flow path 4. On the other hand, the fluid flowing in from the input channel 3 presses the second switching diaphragm 18 in the direction of the pressure chamber 20 against the spring 21.
When the pressure becomes greater than the internal pressure of the pressure chamber 20, the second valve hole 16 opens and the fluid flows out from the second output flow path 5.

When the solenoid 10 is energized, the plunger 15 is attracted to the solenoid 10 against the spring 14, and the first switching diaphragm 8 is separated from the valve seat 7. Therefore, the first valve hole 6 opens and fluid flows out into the first output flow path 4. A part of this fluid is transferred to the pressure chamber 20 via the back pressure guide path 19.
The second switching diaphragm 18 is pressed against the valve seat 17 with the biasing force of the spring 21 to close the second valve hole 16.
No fluid is allowed to flow through the output channel 5.

[0006]

However, in such a switching valve, the spring force of the spring 21 is weak (the spring constant is small) when switching the water supply from the first output flow path 4 to the second output flow path 5. ), the second switching diaphragm moves quickly and the upper wall 2
3 and generates an impact sound. On the other hand, when the spring force is strong (the spring constant is large), no impact noise is generated due to collision with the upper wall 23, but the switching performance of the switching valve deteriorates. The present invention has been made to solve such problems, and its purpose is to obtain a switching valve that reduces abnormal noise when switching water supply from the first output flow path 4 to the second output flow path 5. be.

[0007]

[Means for Solving the Problems] In order to solve the above-mentioned problems, the switching valve according to the present invention has an elastic body provided in the pressure chamber whose elastic coefficient after the valve is opened is compared with the elastic coefficient of the second switching diaphragm at the initial stage of valve opening. The structure is designed to have non-linear elastic properties such that .

[0008]

[Operation] Since the elastic body provided in the pressure chamber is configured to have non-linear elastic characteristics depending on the opening degree of the second switching diaphragm, the The two-switch diaphragm opens quickly at first and then opens forcefully and slowly.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Examples of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a longitudinal cross-sectional view of a switching valve according to a first embodiment of the present invention, and the same parts as those of a conventional switching valve are given the same reference numerals and explanations will be omitted.

In this embodiment, apart from the back pressure guide path 19, a female threaded portion 27-1 is formed on the inner circumference of the communication hole 27 that communicates the first output flow path 4 and the pressure chamber 20. A male threaded portion 22-1 is provided on the outer peripheral surface which is screwed into the female threaded portion 27-1.
An inner spring offset adjustment screw 22 is provided having an inner spring offset adjustment screw 22 on one side. The other side of the inner spring offset adjusting screw 22 has a tapered portion 22-2 having a tapered shape, and a tip portion 22-3 thereof faces a convex portion 18-1 provided on the second switching diaphragm 18. An outer spring 24 with a weak spring force is arranged between the second switching diaphragm 18 and the upper wall 23, and an inner spring 24 with a strong spring force is arranged between the second switching diaphragm 18 and the tapered part 22-2.
5 is disposed with the tapered portion 22-2 side as a free end. Note that a notch (not shown) is formed at the tip of one side and/or the other side of the inner spring offset adjusting screw 22, and by turning this notch to the right or left, the inner spring offset adjusting screw 22 can be adjusted. 22 can be moved forward or backward relative to the second switching diaphragm 18, thereby adjusting the clearance between the internal spring and the step 26 of the internal spring offset adjustment screw 22.

In the above configuration, the water supply from the first output flow path 4 to the second output flow path 5 is switched by stopping the energization of the solenoid 10 to prevent fluid from flowing into the first output flow path 4. Do it by doing this. As a result, the fluid flowing in from the input channel 3 presses the second switching diaphragm 18 in the direction of the pressure chamber 20 . This pressing force first presses the outer spring 24, which has a weak spring force, and quickly moves the second switching diaphragm 18 toward the pressure chamber 20, thereby opening the valve hole 16. Further, as the outer spring 24 is pressed, the free end of the inner spring 25 located at the tapered portion 22-2 comes to abut against the stepped portion 26 of the inner spring offset adjustment screw 22, and the second switching diaphragm 18 The movement gradually becomes slower due to the strong spring force of the inner spring 25. Therefore, the second switching diaphragm 18 does not violently collide with the upper wall 23.

[0012] Also, the second switching diaphragm 18 is connected to the valve seat 1.
7, a clearance is provided between the inner spring 25 and the stepped portion 26 of the inner spring offset adjustment screw 22, so that the inner spring 25 does not affect the switching performance of the switching valve 1. There isn't. In addition, in this example, the elastic body having nonlinear elastic characteristics was composed of two springs.
A single spring may have nonlinear elastic characteristics,
Furthermore, it goes without saying that any elastic body having such characteristics may be used.

[0013]

[Effects of the Invention] As explained above, according to the switching valve of the present invention, the elastic coefficient of the elastic body provided in the pressure chamber after the valve is opened is larger than the elastic coefficient of the second switching diaphragm at the initial stage of valve opening. With this configuration, even if a large pressing force is generated when the water supply is switched from the first output flow path to the second output flow path, the second switching diaphragm and the upper wall will not collide violently and produce an impact sound. have a profit.

[Brief explanation of drawings]

[Fig. 1] Longitudinal cross-sectional view of a switching valve according to the present invention

[Figure 2] Longitudinal cross-sectional view of a conventional switching valve

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1...Switching valve, 2...Casing, 2a...Recess, 3...Input channel, 4...First output channel, 5...Second output channel, 6...First valve hole, 7...Valve seat, 8... First switching diaphragm, 9... Case, 10... Solenoid, 11... Coil, 12... Bobbin,
13...Guide sleeve, 14...Spring, 15...Plunger, 16...Second valve hole, 17...Valve seat, 18...Second switching diaphragm, 18-1...Protrusion, 19...Back pressure guiding path, 20...
...Pressure chamber, 21...Spring, 22...Inner spring offset adjustment screw, 22-1...Male thread, 22-2...Tapered portion, 22-3...
Tip, 23...Top wall, 24...Outer spring, 25...Inner spring, 2
6...Stepped portion, 27...Communication hole, 27-1...Female screw.

Claims (1)

[Claims] 1. A first output flow path and a second output flow path that communicate with an input flow path, and a first switching diaphragm that opens and closes a valve hole provided between the input flow path and the first output flow path. , a second switching diaphragm that opens and closes a valve hole provided between the input flow path and the second output flow path using the internal pressure of the pressure chamber and the pressing force of an elastic body provided in the pressure chamber; and the pressure of the first output flow path. In this switching valve, the elastic body provided in the pressure chamber has an elastic coefficient after opening of the second switching diaphragm compared to an elastic coefficient at the initial stage of opening of the second switching diaphragm. A switching valve characterized by having a nonlinear elastic characteristic that increases in size.