JPS61101814A - Pressure reducing valve - Google Patents

Abstract

PURPOSE:To attain a pressure reducing valve with simple structure by obtaining a thrust in the closing direction with a hollow cylindrical piston valve part having ends with different pressure receiving areas and giving an elastic force against the thrust so as to attain balancing. CONSTITUTION:A fluid flowing from a high pressure side port 6 flows to the inside of a hollow cylindrical piston valve 14 from the upper end of the valve 14 facing a disc valve seat 10, reaches an extended pressure receiving face at a low pressure side and flows out of a low pressure port 24. Then a thrust corresponding to the difference between a force by the fluid pressure received at the high pressure receiving face of the valve 14 and the force due to the fluid pressure at the low pressure extended pressure receiving face is produced. Thus, the valve 14 receives the thrust in opposition to the flowing direction of the fluid. Since the valve 14 is pressed elastically in the same direction as the flowing of the fluid by a coil spring 17 and subject to a valve opening force, the opening of the valve depends on the balance between the opening and closing valve forces, a desired fluid pressure at the low pressure side is obtained regardless of the fluid pressure at the high pressure side.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a pressure reducing valve used for pressure reducing control of equipment using fluid pressure such as air pressure, hydraulic pressure, or water pressure.

(Description of Prior Art) In a conventional pressure reducing valve with automatic control operation, a chamber provided with a valve portion is placed in a controlled fluid path, and a control portion of the valve portion is
A diaphragm installed in a separate chamber from the chamber in which the valve part is placed is operated by control pressure detected from the low pressure side of the valve part, and the movement of the diaphragm is transmitted to the valve part. It had been. Therefore, delicate small parts, small diameter holes, links, etc. are required, and the mechanism becomes quite complex. There were problems with performance, ease of manufacture, economy, ease of maintenance, etc.

(Objective of the Invention) The object of the present invention is to solve the above-mentioned problems of the prior art.

That is, the object of the present invention is to simplify the structure of the pressure reducing valve, ensure reliable operation, robustness, and ease of manufacture:5.
The object of the present invention is to realize a pressure reducing valve that satisfies the requirements of easy quality control, easy maintenance such as inspection and maintenance, and being economical.

(Structure of the Invention) The pressure reducing valve of the present invention has a valve seat provided on the high pressure side connection port side of the body; An enlarged part is provided at one end so that the pressure receiving area is larger than the pressure receiving area at the other end so that a thrust acts in the direction of closing the valve during use, and the end with the smaller pressure receiving area is attached to the valve seat part. a piston valve part that faces each other and is arranged so that the end with a larger pressure receiving area faces the low pressure side connection port; a cylinder part that holds the piston valve part airtight; with respect to the piston valve part; It is characterized by comprising an elastic portion that applies an elastic force that opposes the thrust in the valve closing direction.

Hereinafter, the configuration, operating principles, effects, etc. will be specifically explained using examples.

(Example) FIG. 1 is a sectional view of a pressure reducing valve according to an embodiment of the present invention.

As shown in the figure, one end of the cylinder section 2 is connected to the high-pressure side body 1 via an O-ring 4, and the low-pressure side body 3 is connected to the other end of the cylinder section 2 via an O-ring 5. ing.

A high pressure side connection port 6 is provided on the side of the high pressure side body 1, and a valve seat holding part 8 that holds a valve seat part 7 is airtightly connected to the upper part as seen in the figure via an O ring 9. has been done. A plate-shaped valve seat 1 made of hard rubber or Teflon is located at the bottom of the valve seat part 7.
0 is formed, the connection between the valve seat part 7 and the valve seat part holding part 8 is performed by a threaded part 11, and the upper end of the valve seat part 7 is provided with a screw for turning it with a wrench or the like. An engaging portion 12 is formed. The relative position of the valve seat part 7 with respect to the valve seat part holding part 8 is arbitrarily determined by rotating the valve seat part 7 by its engaging part 12, and the determined relative position is fixed by a lock nut 13.

Although not shown, it is preferable to provide a protective cap to cover the engaging portion 12 and the lock nut 13. Although not shown, in order to protect the engaging portion 12 and the lock nut 13, a protective cap is preferably provided to cover these portions.

A piston valve 14 is connected to the cylinder portion 2 as shown in the figure. The piston valve 14 has a hollow cylindrical shape, and the valve portion 15 is located on the high pressure side (the upper end in the figure).

It faces the valve seat 1o inside the high pressure side body 1.

In the piston valve 14, on the low pressure side opposite to the high pressure side where the valve part 15 is located, an enlarged part 16 is formed to have a diameter larger than the diameter a of the valve part 15, and the lower surface thereof is an enlarged pressure receiving surface. is formed. Cylinder part 2 and piston valve 1
A coil spring 17 is provided between the piston valve 14 and the piston valve 14, and the piston valve 14 is pressed downward by the coil spring 17, and is brought into contact with the low pressure side body 3 in a standby state (not in use). On the side of the cylinder part 2,
A through hole 18 is provided so that the space between the cylinder portion 2 and the piston valve 14 has the same pressure as the outside air. An O-ring 19 is inserted between the inner wall of the cylinder part 2 and the outer wall of the piston valve 14.
°20 is provided. Further, by engaging the flange 21 of the piston valve 14 with the cylinder portion 2, and the enlarged portion 16 of the piston valve 14 engages with the flange 21 of the cylinder portion 2.
A stop for upward movement of the piston valve 14 is formed by engagement with the piston valve 14 .

The low pressure side body 3 has a chamber 2 on the side facing the piston valve 14.
3 is provided, and communicates with the chamber 23 to connect the low pressure side connection port 2.
4 are provided.

The operation of the pressure reducing valve configured as above when in use will be explained.

The fluid flowing in from the high pressure side connection port 6 flows from the upper end of the piston valve 14 facing the plate-shaped valve seat 10 to the piston valve 1
4, reaches the enlarged pressure receiving surface on the low pressure side, and flows out from the low pressure side connection port 24. In this flow, it corresponds to the difference between the loading force due to fluid pressure received at the pressure receiving surface on the high pressure side of the piston valve 14 and the loading force due to fluid pressure received at the enlarged pressure receiving surface on the low pressure side of the piston valve 14. The thrusts received by the piston valve 14 are proportional to the area of the pressure receiving surface, and the pressure receiving surface on the low pressure side has a larger area than the pressure receiving surface on the high pressure side. receives a thrust (valve closing force) that is opposite to the direction of fluid flow. The piston valve 14 is connected to the coil spring 1
7 applies pressure in the same direction as the fluid flow and receives the valve opening force, so the opening degree of the valve is determined by the balance between the valve closing force and the valve opening force, and the fluid pressure on the high pressure side is Control can be performed to obtain a desired fluid pressure on the low pressure side regardless of the situation. That is, when the pressure applied to the expanded pressure receiving surface downstream of the piston valve 14 increases due to the state of the load connected to the low pressure side, the opening degree of the valve becomes smaller, the flow rate is restricted, and the pressure decreases. On the other hand, when the downstream load decreases, the pressure applied to the enlarged pressure receiving surface decreases, and as a result, the valve opening degree is controlled to increase.

Also, the pressure that should be obtained on the low pressure side is the coil spring 17
By appropriately selecting the strength during manufacturing, it is possible to set the desired size. Therefore, by appropriately selecting the coil spring 17 depending on the application, various pressures can be applied over a wide range.

Flow rate products can be easily obtained.
4. Further, the position of the valve seat 10 can be arbitrarily adjusted by loosening the lock nut 13 and then rotating the engaging part 12 with a wrench or the like to turn the threaded part 11. Therefore, if it is necessary to change or adjust the set pressure on the low pressure side depending on the installation location, this can be done extremely easily.6 In particular, in the configuration of the embodiment shown in the figure, the high pressure side connection port 6 can be adjusted. This is because the structure is such that the direction and the direction of the axis of the valve seat portion 7 are at right angles, and the engaging portion 12 for adjustment is pulled out to the outside.

There is an advantage that the position of the valve seat can be easily adjusted from the outside while the pressure reducing valve is installed in the fluid path.

FIG. 2 is a cross-sectional view of an embodiment useful for use when the pressure on the low pressure side is low, and the same symbols are used for the same parts as in the embodiment of FIG.

The main difference compared to the embodiment shown in Figure 1 is that the area ratio between the pressure receiving surface on the high pressure side and the pressure receiving surface on the low pressure side is increased, so that a large thrust can be obtained even with a small pressure. .

In order to increase the area ratio, a diaphragm 25 is used in place of the enlarged portion 16 in FIG. The downstream part of the cylinder part 2 and the low pressure side body 3 connected to it facing the downstream part
One end is enlarged, and a diaphragm 25 is supported on the enlarged part. The center portion of the diaphragm is held between a collar portion 2C provided at the lower part of the piston valve 14 and a pressing plate 27. Since the diaphragm forms the pressure receiving surface on the low pressure side, the pressure receiving surface can be made extremely large without increasing the weight, and a relatively large thrust (valve closing force) can be obtained despite the low pressure. ing.

Note that there are other differences from the embodiment shown in FIG.

In the embodiment shown in FIG. 2, the valve seat holding portion 8 is not separable from the high pressure side body 1 as shown in FIG. 1, but is constructed integrally from the beginning. As in the embodiment shown in FIG.
Although it is not possible to remove the valve seat from the high-pressure side body 1 and adjust the position of the valve seat while visually observing the valve seat, the advantage is that the number of parts is reduced and manufacturing is easy because it is constructed in one piece.

FIG. 3 is a sectional view showing an embodiment in which the high pressure side connection port and the low pressure side connection port are in the same direction, and the high pressure side body 2
8. Low pressure side body 29, valve seat portion 30, piston valve 31
It consists of etc. The high pressure side body 28 is formed with a high pressure side connection port 32 at one end, a support section 33 for supporting a valve seat section in the middle, and a cylinder section 34 at the other end. The valve seat portion 30 is screwed to the support portion 33 so that its position can be adjusted, and the adjusted position is fixed by a lock nut 35.

The low pressure side body 29 has one end connected to the high pressure side body 2.
8, and its interior constitutes a cylinder portion. Further, a low pressure side connection port 39 is formed at the other end. The piston valve 31 is inserted into a cylinder portion formed in the body 28, 29, and is airtightly connected to the cylinder portion via a ring 36, 37. This piston valve 31 has a hollow cylindrical shape, and the diameter of the inlet facing the valve seat is smaller than the diameter of the outlet, and as described in the first embodiment, a thrust in the direction of valve closing is generated due to the difference in pressure receiving area. is configured to occur. A coil spring 38 is provided between the piston valve 31 and the high pressure side body 28, and its elastic force opposes the thrust force.

In use, the pressure reducing valve of this embodiment is inserted into a flow path after adjusting the position of the valve seat. In this case, the inflow and outflow directions of the fluid are the same, whereas the embodiments shown in Figures 1 and 2 differ in that the inflow and outflow directions are at right angles, but the operating principle of pressure reduction control is It's the same. In this embodiment, since the inflow and outflow directions are straight, it can be made compact and has the advantage of not taking up much space.

(Effects of the Invention) As described in detail above, the present invention provides a hollow cylindrical piston valve portion having different ends of a pressure receiving surface tank with a thrust force in the sliding valve closing direction, and an elastic force applied to the thrust force. The structure is extremely simple and easy to manufacture because the pressure and flow rate are controlled so that these forces are balanced.

Further, since the elastic portion such as a coil spring can be selected to have an appropriate strength depending on the application, it is possible to control pressure and flow rate over a wide range.

Furthermore, according to the present invention, there is no need for a delicate control unit configuration, and the number of parts is reduced, making quality control easier, making the product more robust, increasing operational stability, and making maintenance easier. Become.

Furthermore, it has a long life and is also excellent in economical efficiency.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a pressure reducing valve according to an embodiment of the present invention. FIG. 2 is a cross-sectional view of an embodiment useful for use when the pressure on the low pressure side is low. FIG. 3 is a sectional view showing an embodiment in which the high pressure side connection port and the low pressure side connection port are in the same direction. 1. 28...High pressure side body, 2...Cylinder part, 3. . 29...Low pressure side body, 4.5. ．． 9.19.2
0...O ring, 6,32...High pressure side connection 0.7
．． 30... Valve seat part, 8... Valve seat part holding part, lO...
-Valve seat, 11...screwing part, 12...engaging part, 13.
35...Lock nut, 14.31...Piston valve, 15...Valve part, 16...Enlarged part, 17.38...
Coil spring, 18, 40... Through hole, 21, 2
2...Protruding edge. 23... Chamber, 24... Low pressure side connection port, 25...
Diaphragm, 26...flange, 27...pressing plate.

Claims (4)

[Claims] (1) The valve seat provided on the high-pressure side connection port side of the body is hollow and cylindrical so that fluid can pass through, and the pressure-receiving area at one end of the cylindrical shape is the pressure-receiving area at the other end. An enlarged part is provided at one end of the valve so that thrust acts in the direction of closing the valve during use due to its larger size. a piston valve portion disposed such that its end portion faces the low pressure side connection port; a cylinder portion that airtightly holds the piston valve portion; and a cylinder portion that opposes the thrust force in the valve closing direction to the piston valve portion. A pressure reducing valve characterized by comprising an elastic part that imparts elastic force. (2) In order to adjust the relative positional relationship of the valve seat with respect to the cylinder and piston valve, screw threads are formed on the valve seat and the body, respectively, and screwed together to lock the adjusted position. The pressure reducing valve according to claim 1, wherein the pressure reducing valve is fixed with a nut. (3) The axial direction of the screw part for adjusting the position of the valve seat part is arranged so that the direction of the high pressure side connection port is almost perpendicular, and the head of the screw part is located outside the body. The pressure reducing valve according to claim (2), wherein the pressure reducing valve is adapted to project from the outside, and the position of the valve seat portion can be adjusted from the outside. (4) The pressure reducing valve according to any one of claims (1) to (3), wherein the enlarged portion of the piston valve portion is constituted by a diaphragm.