JPH0932943A - Umbrella valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To dispense with a different relief valve to arrange for release of a back pressure by a method wherein when a back pressure exceeding a specified value is exerted on an umbrella-form part arranged at the valve column of an umbrella valve, the valve column is moved to intercommunicate the front and the rear of a partition wall, and an external communication passage is opened. SOLUTION: An umbrella valve body 20 comprises a first umbrella-form part 21; and a second umbrella-form part 24 fitted in a shaft column 23 extending from the center of a thick section part 22. A back pressure exceeding a specified value is exerted on the umbrella valve body 20, the first umbrella-form part 21 continues closing of a relief groove 15 until a movement amount of the shaft column 23 exceeds a specified value and the second umbrella-form part 24 continues closing of the opening end part 19a of an external communication passage 19. When the movement amount of the shaft column 23 exceeds the specified value, the first umbrella-form part 21 is resiliently deformed along a taper-form inner wall 13a, and the end part of the relief groove 15 covered with the first umbrella-form part 21 is opened. In which case, the relief groove 15 communicates the with a relief passage through a communication hole 16 and fluid flows from the surface side of a first partition wall 12A to the back thereof.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an umbrella valve having a relief function and a backflow prevention function.

[0002]

[Prior art and its problems]

An umbrella valve in which an umbrella-like portion and a shaft column at the center thereof are integrally formed from an elastic material is widely used as a small, lightweight and inexpensive check valve (one-way valve). The partition wall of the flow path in which the umbrella valve body is mounted is provided with a shaft column support hole through which the shaft column is inserted and supported, and a circulation hole closed by the umbrella-shaped portion. In this umbrella valve, when a fluid pressure (positive pressure) acts on the umbrella-shaped portion through the circulation hole, the umbrella-shaped portion is deformed to separate from the partition wall and open the circulation hole to allow a fluid flow. Conversely, when a fluid pressure (reverse pressure) is applied to the umbrella-shaped portion in the direction of being pressed against the partition wall, the umbrella-shaped portion enhances the adhesion force with the partition wall and blocks the fluid flow.

The above-mentioned backflow preventing function is maintained regardless of the magnitude of the fluid pressure acting on the umbrella-shaped portion in the direction of being pressed against the partition wall. This function is an essential function as an umbrella valve in one aspect, but even if the back pressure becomes extremely large, a backflow preventing function works unless the umbrella-shaped portion is broken. Therefore, when the back pressure may be significantly large, it is necessary to provide a relief valve in parallel with the umbrella valve that opens when the back pressure exceeds a certain value.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to provide the umbrella valve itself with a relief function so that it is not necessary to separately provide a relief valve for releasing the back pressure. Further, it is an object of the present invention to obtain an umbrella valve in which the back pressure does not act on the forward pressure side flow passage as it is even when the relief function works.

[0006]

SUMMARY OF THE INVENTION According to the first aspect of the umbrella valve of the present invention, a valve column of the umbrella valve is provided with first and second umbrella-shaped portions that are separated from each other by a certain distance, and a partition wall that closes a flow passage,
A communication passage that is normally closed by the first umbrella-shaped portion and that is opened by deforming the first umbrella-shaped portion when positive pressure acts, and an external communication passage that is normally closed by the second umbrella-shaped portion. Further, a means for allowing the valve column to move when a back pressure above a certain level acts on the first umbrella-shaped portion, a relief means for communicating the front and rear of the partition when the valve column moves, and the valve column moves. In this case, a means for opening the external communication path by the second umbrella-shaped portion and for communicating the reverse pressure side flow path to the outside through the external communication path and the relief means is provided. It is preferable that the valve is further provided with a valve element that disconnects the communication between the back pressure side channel and the forward pressure side channel when the valve body moves.

According to a more specific aspect of the present invention, in an umbrella valve including a valve main body made of an elastic material and a valve support portion in a flow path for supporting the valve main body, the valve main body has a first structure. An umbrella-shaped portion; a shaft pillar integrally formed with a shaft portion of the first umbrella-shaped portion; a second umbrella-shaped portion provided on the shaft pillar and paired with the first umbrella-shaped portion; a shaft pillar And a valve portion integrated with the valve support portion, and the valve support portion is formed between the forward pressure side flow passage and the reverse pressure side flow passage. And a communication hole that is opened and closed by the valve portion of the valve body; a partition that separates the backflow prevention chamber and the pressure-increasing passage; and a shaft support hole that is pierced in the partition and movably supports the shaft of the valve And; a flow hole closed by the first umbrella-shaped portion; and a back pressure of a certain amount or more in the direction of pressing the first umbrella-shaped portion against the partition wall. A recess that allows the first umbrella-shaped portion and the shaft column to move in the same direction when used; a relief passage that communicates the front and rear of the partition wall when the first umbrella-shaped portion moves into the recess; And an external communication passage having one end opening to the partition wall. The second umbrella-shaped portion of the valve body normally closes one end opening of the external communication passage, opens the one end opening when the shaft column moves due to back pressure, and the valve portion of the valve body always The communication hole is opened, and the communication hole is closed when the shaft column moves due to the back pressure. The relief passage can be composed of, for example, a relief groove bored in the inner surface of the recess and the communication hole communicating with the relief groove.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described below with reference to illustrated embodiments. In the flow path 11, first and second partition walls 12A and 12B are formed so as to block the flow path. The first partition 12A has a tapered recess 13, a shaft support hole 14,
A relief groove 15 and a communication hole 16 are formed. The tapered recess 13 has a tapered inner wall 13a whose diameter is gradually reduced from the front surface side (upper side in the drawing) of the partition wall 12 to the inner portion.
And a bottom wall 13b parallel to the surface of the first partition 12A, and a shaft support hole 14 is formed in the center thereof. The relief groove 15 is formed along the slope of the tapered inner wall 13a, and the upper end portion thereof has the first partition wall 12a.
It has reached the surface of A (reverse pressure side flow path 11B). In the illustrated example, four relief grooves 15 are formed at 90 ° intervals. One end of the communication hole 16 has the relief groove 1
5 communicates with the middle portion of the first partition wall 5, and the other end portion opens to the back surface of the first partition wall 12A. The relief groove 15 and the communication hole 16 are
It is a forward flow passage that flows from the back surface side to the front surface side of the first partition wall 12A, and is also a reverse flow relief passage that allows the fluid to flow from the front surface side to the back surface side when the back pressure exceeds a certain value.

A backflow preventing chamber 17 is formed between the first partition 12A and the second partition 12B. The backflow prevention chamber 17 and the forward pressure side flow passage 11A are communicated with each other by a communication hole 18 formed in the center of the second partition 12B. An end edge of the communication hole 18 on the backflow prevention chamber 17 side forms an annular valve seat 18a.

The first partition 12A has an external communication passage 19 whose one end opens to the backflow prevention chamber 17 and whose other end opens to the outside.
Are formed. Backflow prevention chamber 1 of this external communication passage 19
The opening end 19 a on the seventh side is located around the shaft support hole 14.

The umbrella valve body 20 is made of an elastic material such as rubber, and has a first umbrella-like portion 21, a thick portion 22 at the center thereof, and a shaft column 23 extending from the center of the thick portion 22. The second umbrella-shaped portion 24 fitted and fixed in the annular groove 23a of the shaft column 23.
And a valve body projection 25 that is integrally provided on the shaft post 23 from the top of the drawing. First umbrella-shaped portion 21 and second umbrella-shaped portion 24
Has an umbrella shape in which the tip portion thereof is in strong contact with the first partition wall 12A, and the diameter of the first umbrella portion 21 is the circumscribed circle of the diameter of the tapered concave portion 13 and the tip portion of the relief groove 15. The diameter of the second umbrella-shaped portion 24 is sufficiently larger than the diameter of the second umbrella-shaped portion 24 and is large enough to position the opening end portion 19a of the external communication passage 19 inside thereof.
When the valve body projection 25 is seated on the annular valve seat 18a of the communication hole 18, the forward pressure side flow passage 11A and the backflow prevention chamber 17 are provided.
Cut off communication with.

At the time of assembly, the shaft column 23 of the umbrella valve body 20 is inserted into the shaft column support hole 14 from the tapered recess 13 side and pulled from the back surface of the first partition wall 12A. Then, the valve body projection 25 is deformed and enters the shaft support hole 14, and eventually protrudes to the back surface of the first partition wall 12A to return to the original shape and is prevented from coming off. The second umbrella-shaped portion 24, in this state, is the shaft 2
3 is fitted and locked in the annular groove 23a. A tapered surface 14 a that facilitates the deformation of the valve body projection 25 is formed at the entrance of the shaft support hole 14. FIG. 1 shows this assembled state, and the tip end portion of the first umbrella-shaped portion 21 covers the tapered concave portion 13 and the relief groove 15. The members forming the flow path 11 are
Although it is a single member in the figure, it has a divided structure as appropriate in order to enable the above assembly of the umbrella valve body 20.

In the umbrella valve having the above structure, the counter pressure P'in the counter pressure side passage 11B acts on the umbrella valve body 20. When this back pressure P'is smaller than a certain value, the first umbrella-shaped portion 21 is simply pressed against the surface of the first partition 12A to prevent backflow (FIG. 1). On the other hand, via the communication hole 18, the backflow prevention chamber 17, the communication hole 16 and the relief groove 15,
When the positive pressure P of the forward pressure side channel 11A acts on the back surface of the first umbrella-shaped portion 21, the first umbrella-shaped portion 21 elastically deforms to open the channel (FIG. 2). That is, a normal flow is made to flow. At this time, the valve body projection 25 of the shaft post 23 engages with the end of the shaft post support hole 14,
The movement of the thick portion 22 is prevented. The above is the function of the normal check valve (one-way valve) of the umbrella valve.

On the other hand, when the back pressure PP exceeding a certain value acts on the umbrella valve body 20, the thick portion 22 at the center thereof begins to fall into the tapered recess 13, as shown in FIG. However, until the movement amount of the shaft column 23 exceeds a certain value,
The first umbrella-shaped portion 21 continues to close the relief groove 15, and the second umbrella-shaped portion 24 continues to close the open end portion 19a of the external communication passage 19 (FIG. 3). When the amount of movement of the shaft column 23 exceeds a certain value, the first umbrella-shaped portion 21 moves to the tapered inner wall 13 as shown in FIG.
It elastically deforms along a, and the end of the relief groove 15 covered by the first umbrella-shaped portion 21 opens. Then, the relief groove 15 and the relief passage formed by the communication hole 16 communicate with each other, and the fluid flows from the front surface (reverse pressure side flow passage 11B) side of the first partition 12A to the rear surface (backflow prevention chamber 17) side. This first umbrella-shaped portion 21
Almost at the same time as the relief action by the umbrella valve body 20
The valve body projection 25 is seated on the annular valve seat 18a of the communication hole 18 to cut off the communication between the forward pressure side flow passage 11A and the backflow prevention chamber 17. In order to ensure the closed circuit by the valve body projection 25, the clearance c (when the valve body projection 25 is seated on the annular valve seat 18a) is provided between the lower surface of the thick portion 22 and the bottom wall 13b of the tapered recess 13. (Fig. 4) is set.

Therefore, the high-pressure fluid on the reverse pressure side flow passage 11B side is guided to the outside through the relief groove 15, the communication hole 16, the backflow preventing chamber 17 and the external communication passage 19, and the reverse pressure side flow passage 11B.
The large back pressure on the side does not act on the normal pressure side channel 11A side. Therefore, not only can the danger due to the pressure on the reverse pressure side flow channel 11B side exceeding a certain value be eliminated, but also the high pressure on the reverse pressure side flow channel 11B side can be prevented from reaching the normal pressure side flow channel 11A side. . Then, when the back pressure becomes equal to or less than a certain value, the umbrella valve body 20 returns to the state of FIG. 1 again due to the elasticity of the first umbrella-shaped portion 21.

The valve body projection 25 of the umbrella valve body 20 is preferably provided, but it can be omitted. When the backflow prevention chamber 17 communicates with the outside when the relief function of the umbrella valve body 20 is activated, it is possible to suppress the pressure increase on the forward pressure side flow passage 11A side. Further, when it is necessary to more reliably prevent the high-pressure fluid on the pressure-increasing side flow passage 11A side from flowing, it is possible to separately provide a normal umbrella valve on the second partition 12B.

Further, in the above embodiments, the relief groove 15 and the communication hole 16 are provided with the relief passage, but the relief passage may be provided independently of the communication hole 16. For example, even if the relief passage 15 ′ is provided at the position shown by the chain line in FIG. 1 and the relief groove 15 is abolished, the same effect can be obtained.

[0018]

As described above, the umbrella valve of the present invention has the function of a check valve up to a certain back pressure and acts as a relief valve when the back pressure exceeds a certain value, so that it is a special relief valve. There is an advantage that the relief action can be obtained without providing the above, and the back pressure does not directly act on the forward pressure side flow path even if the relief action works.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of an assembled state showing an embodiment of an umbrella valve according to the present invention.

FIG. 2 is a cross-sectional view of the umbrella valve of FIG. 1 in a state where the umbrella valve is opened by positive pressure.

FIG. 3 is a cross-sectional view of the umbrella valve of FIG. 1 in a state in which a valve column has started to move due to back pressure.

FIG. 4 is a cross-sectional view of the umbrella valve of FIG. 1 in a state where a relief action is generated by back pressure.

[Explanation of symbols]

 11 Flow Path 11A Normal Pressure Side Flow Path 11B Reverse Pressure Side Flow Path 12A First Partition Wall 12B Second Partition Wall 13 Tapered Recess 14 Shaft Support Hole 15 Relief Groove 15 'Relief Passage 16 Communication Hole 17 Backflow Prevention Chamber 18 Communication Hole 20 Umbrella Valve Body 21 First umbrella-shaped portion 22 Thick-walled portion 23 Shaft column 24 Second umbrella-shaped portion 25 Valve body projection

Claims (4)

[Claims] 1. A valve column of an umbrella valve is provided with first and second umbrella-shaped portions that are separated by a certain distance, and a partition wall that blocks a flow path is normally closed by this first umbrella-shaped portion and positive pressure is applied. When the first umbrella-shaped portion is deformed and opened, a communication passage and an external communication passage that is normally closed by the second umbrella-shaped portion are provided. A means for allowing the valve post to move when a back pressure is applied, a relief means for communicating the front and back of the partition when the valve post moves, and a second umbrella-shaped part for opening the external communication passage when the valve post moves. A means for communicating the reverse pressure side flow path to the outside via the external communication passage and the relief means. 2. The umbrella valve according to claim 1, further comprising a valve body that interrupts communication between the reverse pressure side passage and the positive pressure side passage when the valve body moves. 3. A valve main body made of an elastic material, and a valve support portion in a flow path for supporting the valve main body, wherein the valve main body has a first umbrella-shaped portion; and a shaft portion of the first umbrella-shaped portion. A shaft pillar integrally formed with the shaft pillar; a second umbrella-shaped portion provided on the shaft pillar and forming a pair with the first umbrella-shaped portion; a valve portion integrated with the shaft pillar; The support portion is a backflow prevention chamber formed between the flow passage on the normal pressure side and the flow passage on the reverse pressure side; a communication that connects the backflow prevention chamber and the flow passage on the pressure compression side and is opened and closed by the valve portion of the valve body. A hole; a partition wall separating the backflow prevention chamber and the pressure-increasing side passage; a shaft column support hole formed in the partition wall to movably support a shaft column of the valve body; and a flow hole closed by the first umbrella-shaped portion. A recess that allows the first umbrella-shaped portion and the shaft column to move in the same direction when a back pressure of a certain amount or more in the direction of pressing the first umbrella-shaped portion against the partition wall is applied. When; first cone-shaped part is when moved into the recess, a relief passage and which communicates the front and rear of the partition wall; communicating the backflow prevention chamber to the outside,
An external communication passage having one end opening to the partition wall; and the second umbrella-shaped portion of the valve body normally closes the one end opening of the external communication passage, and the one end opening when the shaft column moves due to back pressure. An umbrella valve, characterized in that the valve section of the valve body is always opened, and the communication hole is closed when the shaft column is moved by a back pressure. 4. The umbrella valve according to claim 3, wherein the relief passage includes a relief groove formed on an inner surface of the recess and the communication hole communicating with the relief groove.