JPH0313652Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a check valve, and particularly to one having an umbrella-shaped valve body made of a rubber-like elastic material.

(Prior art) Conventionally, as this type of check valve, for example, a fourth check valve is used.
There is something like the one shown in the figure. That is, 100 is a housing, and the internal flow path is partitioned by a partition wall 101 into a first fluid chamber A and a second fluid chamber B. On the other hand, 102 is an umbrella-shaped seal made of a rubber-like elastic material, and consists of an umbrella-shaped valve body 103 at the head and a shaft portion 104 connected to the valve body 103, and the shaft portion 104 has a mounting hole provided in the partition wall 101. 105. Around the mounting hole 105 of the partition wall 101, there is a small hole 10 that communicates the first and second fluid chambers A and B.
6 is bored and opens into the valve seat 107, and is closed by the valve body 103 which is pressed against the valve seat 107. That is, the shaft portion 104 is provided with a locking portion 108 for preventing the valve from coming off, and the valve body 103 is locked in pressure contact with the valve seat 107. In the case of a check valve having such a configuration, the first fluid chamber A
When the pressure in the first fluid chamber A becomes greater than the pressure in the second fluid chamber B and reaches the set pressure, the valve body 103 bends upward and a gap opens between it and the valve seat 107, and the pressure in the first fluid chamber A increases to the second pressure. It is released to the fluid chamber B side. On the other hand, when the pressure in the first fluid chamber A decreases to below the set pressure, the valve body 103 closes to prevent backflow of fluid.

(Problems to be Solved by the Invention) However, in the case of such a conventional example, the valve body 103 is usually made of a rubber material and has stickiness, and the valve body 103 does not stay on the valve seat 107 for a long period of time. When the valve body 103 is in pressure contact, the valve body 103 sticks to the valve seat 107, and the adhesive force between the two causes the valve opening pressure to become larger than the set value. Therefore, the check valve does not operate at a predetermined valve opening pressure, resulting in a problem that various control devices controlled by fluid pressure cannot be accurately controlled.

The present invention was made in order to solve the problems of the prior art described above, and its purpose is to provide a check valve that can reduce as much as possible the adhesive force between the valve body and the valve seat when the valve is closed. The object of the present invention is to provide a valve opening pressure and prevent fluctuations in valve opening pressure.

(Means for Solving the Problems) In order to achieve the above object, the check valve according to the present invention includes a shaft portion that is attached to a mounting hole provided in a partition wall that partitions a fluid flow path, and a shaft portion that is attached to a mounting hole provided in a partition wall that partitions a fluid flow path. and a flexible valve body that closes a pore formed in the partition wall that opens in close contact with the valve seat provided at the periphery of the mounting hole. In a region of the valve seat inside the outer diameter of the valve body, the periphery of the pore is a seating area where the valve body comes into close contact, and a recessed portion with which the valve body does not come into contact is formed in an area other than the seating area. It consists of

(Function) In the present invention, since a recess is provided in the valve seat,
The contact area between the valve body and the valve seat when the valve body is seated is small, and even if they stick together, the adhesive force will be small.

(Example) The present invention will be explained below based on the illustrated example. A first diagram showing a check valve according to an embodiment of the present invention.
In the drawings to FIG. 3, reference numeral 1 denotes an umbrella-shaped seal consisting of an umbrella-shaped valve body 2 and a shaft portion 3, which are integrally molded from a rubber-like elastic body. This umbrella-shaped seal 1 is attached to a partition wall 5 that divides the flow path inside the housing 4 into first and second fluid chambers A' and B'. That is, the shaft portion 3 is inserted through a mounting hole 6 formed in the partition wall 5, and a locking portion 7 for locking the partition wall 5 and preventing it from coming off is provided in the middle of the shaft portion 3. Locking part 7
is formed by partially bulging the tip.

To explain the umbrella-shaped seal 1 in detail, the shaft portion 3
It is formed by a tongue piece that bulges out from the base in the radial direction over the entire circumference, and the tongue piece has a downwardly tapered shape and has a substantially umbrella shape. When the fluid pressure on the first fluid chamber A' side is higher than the fluid pressure on the second fluid chamber B' side, the valve body 2 is pressed against the valve seat provided around the mounting hole 6 by the back pressure applied to the top surface of the valve body 2. 8. A small hole 9 is bored around the mounting hole 6 of the partition wall 5 to communicate the first fluid chamber A' and the second fluid chamber B', and opens into the valve seat 8.

As shown in FIGS. 2 and 3, the valve seat 8 is provided with a recess 10 in an area other than the periphery of the opening of the pore 9. That is, the pores 9 are symmetrically provided at four locations around the mounting hole 6 at predetermined intervals, a recess 10 is provided between each pore 9, and the shape of the seating area c of the valve seat 8 is similar to that of the mounting hole. It has a substantially cross shape extending from the periphery of 6 to the periphery of each pore 9. The corners of the recess 10 are formed at right angles to improve sealing performance when the valve body 2 is pressed into contact with the valve body 2. The recess 10 may be provided so as to leave at least the periphery of the opening of the pore 9.
The shape of the recess 10 is arbitrary. Further, the number and arrangement of the pores 9 are arbitrary.

In the case of the check valve having the above configuration, the first fluid chamber
When the pressure in A' is lower than the pressure in the second fluid chamber B', the valve body 2 is bent by the pressure and comes into pressure contact with the valve seat 8, thereby closing the opening of the pore 9. Valve seat 8 of valve body 2
The contact area with the recess 10 is reduced by the amount
The adhesive force with the valve seat 8 is small even when the valve seat 8 is in pressure contact with the valve seat 8 for a long period of time. Further, since the seating area c of the valve seat 8 is narrow, the contact surface pressure between the valve body 2 and the valve seat 8 is high, and good sealing performance is maintained.

On the other hand, when the pressure in the first fluid chamber A' becomes higher than the pressure in the second fluid chamber B', the valve body 2 is bent toward the second fluid chamber B', the opening of the pore 9 opens, and the first fluid chamber A The fluid flows out from ' to the second fluid chamber B' through the pore 9, the pressure in the first fluid chamber A' is released, and when the pressure in the first fluid chamber A' further drops to the set pressure, the valve body 2 is released again. is seated and the opening of the pore 9 is closed.
Even if the valve body 2 is pressed against the valve seat 8 for a long period of time and the valve body 2 sticks to the valve seat 8, the contact area between the valve body 2 and the valve seat 8 will be reduced by the recess 10. Therefore, the adhesive force is small and the increase in valve opening pressure is reduced (effect of the invention). , the contact area between the valve body and the valve seat is small when the valve body is seated, and the adhesive force between the valve body and the valve seat due to long-term contact is reduced as much as possible.
It is possible to prevent the valve opening pressure from increasing, and the reliability of the check valve is improved. Further, since the recess is provided on the valve seat side, there is no need to perform any processing on the valve body, and the predetermined opening/closing characteristics of the valve body can be maintained.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view of a check valve according to an embodiment of the present invention, FIG. 2 is a plan view of the valve seat of the device shown in FIG. 1, and FIG. 3 is a sectional view taken along the - line in FIG. FIG. 4 is a longitudinal sectional view of a conventional check valve. Explanation of symbols 2... Valve body, 3... Shaft, 5... Partition wall, 6... Mounting hole, 8... Valve seat, 9... Pore, 10... Recess, A'... First fluid chamber, B'... Second Fluid chamber, c...seating area.

Claims (1)

[Scope of Claim for Utility Model Registration] A shaft portion that is attached to a mounting hole provided in a partition wall that partitions a fluid flow path, and a shaft portion that is connected to the shaft portion and that is fully in close contact with a valve seat provided at the periphery of the mounting hole. In the check valve, the check valve is equipped with a flexible valve body that closes a pore formed in the partition wall that opens into the valve seat;
A check valve characterized in that the periphery of the pore is a seating area in which the valve element comes into close contact, and a recess with which the valve element does not come into contact is formed in an area other than the seating area.