JPH07104730B2 - Pressure reducing / relief valve - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention connects a pressure-sensitive plate that senses and operates a secondary pressure to a pressure reducing valve that controls opening and closing of communication between the primary side and the secondary side. hand,
The present invention relates to a pressure reducing / releasing valve in which a pressure reducing valve configured to hold the pressure on the secondary side within a set pressure is incorporated with a relief valve that releases the pressure due to an abnormal increase in pressure on the secondary side.

[Prior Art] A pressure reducing valve which is connected to a pipe of a hot water supply facility such as a boiler and holds water or hot water supplied from the primary side within a predetermined set pressure and supplies it to the secondary side is Usually, when an abnormal pressure occurs on the secondary side, it is used in combination with a relief valve that releases the pressure to the outside. The pressure reducing valve for controlling the pressure on the secondary side below the set pressure and the relief valve for releasing the abnormal pressure generated on the secondary side to the outside have been manufactured and used separately in the past. At the time of, they are attached to each pipe while combining them.

As one in which a pressure reducing valve and a relief valve are incorporated in one valve box, for example, it is conventionally known as disclosed in Japanese Utility Model Laid-Open No. 58-54710, but this one has a pressure on the primary side. Is bypassed to the secondary side by a bypass passage and a relief valve that opens and closes the bypass passage, and not the pressure generated on the secondary side to the outside. As a countermeasure against abnormal pressure on the secondary side, a communication hole is provided at the bottom of the valve box that communicates with the secondary side, and a communication hole communicating with the outside is provided. The drain valve is biased toward the valve closing side by the closing spring, and when the drain valve receives a pressure higher than the spring pressure set in the closing spring through the communication hole, the drain valve Is designed to act as a relief valve that releases abnormal pressure on the secondary side to the outside.

[Problems to be Solved by the Invention] The above-mentioned conventional means includes a pressure reducing valve for controlling the pressure of hot water supplied from the primary side to the secondary side within a predetermined set pressure,
There is a problem in that mounting work is troublesome in a means for separately making a relief valve for releasing an abnormal pressure generated on the secondary side to the outside and connecting the relief valve to the pipe in combination. Also, in the valve box of the pressure reducing valve, a means for incorporating a bypass passage for releasing the primary pressure to the secondary side and a relief valve for opening and closing the bypass passage should be installed on the secondary side when used for piping of hot water supply facilities such as boilers. There is a problem that it cannot be used at all as a means for ensuring safety by releasing the generated abnormal pressure to the outside.

In addition, as disclosed in Japanese Utility Model Laid-Open No. 58-54710, a drain valve is provided at the bottom of the valve box in communication with the secondary side, and the drain valve is urged toward the valve closing side by a closing spring to The means that doubles as a relief valve for releasing abnormal pressure generated on the outside to the outside is that the pressure on the secondary side is transmitted to the drain valve through the communication hole that is the drain hole, and Since the pressure receiving area with respect to the pressure on the secondary side is remarkably reduced, the sensitivity of responding to the pressure change on the secondary side is low, which causes various problems. That is, when setting the spring pressure of the closing spring such that the relief valve opens when the pressure on the secondary side becomes higher than the set pressure with reference to the set pressure of the hot water set by the pressure reducing valve. If the spring of the closing spring is weakened so that the pressure at which the relief valve opens will be close to the set pressure set by the pressure reducing valve, this relief valve will be activated when the pressure on the secondary side is equal to or lower than the set pressure set by the pressure reducing valve. In some cases, the valve will open, impairing the function of the pressure reducing valve. Also, if the spring pressure of the closing spring is increased in consideration of safety, the relief valve may not open even when the pressure on the secondary side becomes much higher than the set pressure set by the pressure reducing valve. Then, there arises a problem that the device connected to the secondary side is damaged.

The present invention has been made in order to eliminate these problems that have occurred in the conventional means, and a relief valve that releases an abnormal pressure generated on the secondary side to the outside is incorporated in the valve box of the pressure reducing valve. When constructing a pressure reducing / relief valve,
A pressure relief plate with a wide pressure receiving area is used to make a relief valve with good sensitivity by connecting to the pressure sensitive plate so that opening and closing can be controlled by the operation of the pressure sensitive plate that performs decompression operation on the pressure reducing valve. Abnormal pressure does not interfere with the predetermined pressure reducing operation by the pressure reducing valve, and when the pressure on the secondary side further rises with reference to the set pressure set by the pressure reducing valve, it is sensitive It is an object of the present invention to provide a new means for forming a pressure reducing / releasing valve that detects it and allows it to be released to the outside correctly and promptly.

[Means for Solving the Problem] In the present invention, as a means for achieving the above-mentioned object, a pressure reducing valve for controlling opening / closing of communication between a primary side and a secondary side provided in a valve box is provided. , The lower end side of a valve rod having a balancing piston on the upper end side is connected, and a vertically penetrating rod is slidably inserted into the axial center portion of the valve rod,
An upper end side of the rod is connected to a pressure sensitive plate that senses and operates a secondary pressure, and a relief valve is provided at a lower end portion of the rod protruding below the pressure reducing valve in a longitudinal direction of the rod. A stopper for restricting downward movement of the relief valve to the rod is provided at a predetermined position, and the spring for pushing the relief valve toward the stopper is connected to the relief valve. The valve opening for the relief valve, which is opened and closed by the relief valve, is provided outside at the bottom of the valve box,
The present invention proposes a pressure reducing / releasing valve in which the upper end side of the valve rod is butted against the lower surface of the pressure sensitive plate so as to freely come into contact with and come into contact with the lower surface of the pressure sensitive plate.

Example Next, an example will be described in detail with reference to the drawings.

FIG. 1 is a vertical sectional view of a pressure reducing / releasing valve A embodying the present invention. In FIG. 1, 1 is a valve box, and 20 is a communication between the primary side X and the secondary side Y in the valve box 1. A pressure reducing valve 3 provided to control opening and closing, a valve rod 3 having a balancing piston 30 on the upper end side and a lower end portion connected to the pressure reducing valve 20, and 4 is a vertical portion at the axial center portion of the valve rod 3. A pressure-sensitive plate 5 that senses and operates a secondary pressure, and a rod 60 for a relief valve that is slidably fitted in the lower end of the rod 4 in the longitudinal direction of the rod 4. A valve, S is a stopper for restricting a downward movable range of the relief valve 60 with respect to the rod 4, and 61 is a relief provided at the bottom of the valve box 1 so that the relief valve 60 is controlled to open. Reference numeral 70 denotes a valve opening for the valve, and 70 denotes a spring provided so as to push the valve 60 for the relief valve toward the stopper S.

The valve box 1 includes a valve box body 1a having an inlet side connecting pipe 10 on one side and an outlet side connecting pipe 11 on the other side, and the valve box body 1a.
And a spring case 1b assembled in a cap shape on the upper surface of the. Then, in the lumen of the valve box body 1a, the connection pipe on the inlet side
A partition wall 12 that separates a primary side X communicating with 10 and a secondary side Y communicating with the outlet side connecting pipe 11 is provided, and a cylindrical portion 13 whose axial direction is the up-down direction defines the body portion of the partition wall 12. It is installed so as to communicate with the primary side X, and in this cylindrical portion 13, the balancing piston 30 provided on the upper end side of the valve rod 3 is provided.
Is fitted in a watertight manner and is slidably inserted vertically.
The above-described pressure reducing valve 20 is integrally assembled to the lower end portion of the valve rod 3 which projects downward from the opening below the tubular portion 13. Further, a pressure reducing valve seat 21 facing the pressure reducing valve 20 is formed on the edge of the opening below the tubular portion 13.

A pressure-sensitive chamber W communicating with the secondary side Y is formed on the upper surface side of the valve box body 1a, and the pressure-sensitive plate 5 is attached so as to cover the pressure-sensitive chamber W. When the spring case 1b is fixed to the upper surface of the valve box main body 1a by a set screw, the peripheral edge of the pressure sensitive plate 5 is fixed to the spring case 1b and the valve box main body 1a.
It is assembled to the valve box 1 by inserting it into the joint part.
Then, the adjusting screw 80 screwed on the upper part of the spring case 1b
And a pressure reducing spring 2a stretched between the pressure sensing plate 5 and the upper surface of the pressure sensing plate 5 to push the pressure sensing chamber 5 toward the pressure sensing chamber W.

The rod 4 is the valve rod 3 fitted in the cylindrical portion 13 described above.
It is formed to be longer, and is inserted into the axial center portion of the valve rod 3 so as to vertically penetrate the valve rod 3 and slide freely in the vertical direction. An upper end portion 4a of the rod 4 protruding upward from the valve rod 3 is formed in a flat plate shape and abuts against the lower surface of the pressure sensitive plate 5, and is planted on the upper surface side of the upper end portion 4a. The pressure-sensitive plate 5 is integrally connected to the pressure-sensitive plate 5 by projecting the screw 4b to the upper surface side of the pressure-sensitive plate 5 and tightening the screw 4b.

Further, the lower end side of the rod 4 projects downward from the pressure reducing valve 20 for a long time, and the above-mentioned relief valve valve 6 is provided at the projecting portion.
Is slidably inserted in the axial direction (longitudinal direction) of the rod 4, and the movable range of the rod 4 is restricted by a stopper S formed of a retaining ring provided at the lower end of the rod 4. Escape from 4 is blocked.
The relief valve 60 is pushed toward a position where it abuts against the stopper S by a weak spring 70 stretched between the relief valve 60 and the lower end of the valve rod 3.

The opposing relief valve valve opening 61 of the relief valve valve 60 is formed at the bottom portion of the valve box body 1a so as to be opened to the outside at a portion located below the aforementioned cylindrical portion 13. Below that, a connecting pipe 14 for connecting a pipe for guiding the pressure discharged from the valve opening 61 serving as the escape port to a desired location is continuously installed. An annular valve seat 62 is formed on the edge of the valve opening 61 so as to come into contact with the relief valve 60 and come into contact with the relief valve 6 to form the relief valve 6.

Thus, the upper end side of the valve rod 3 projects into the pressure sensing chamber W from the open portion above the cylindrical portion 13 and the end face 3a of the upper end thereof is formed.
Is abutted against the lower surface of the flat plate-shaped upper end portion 4a of the rod 4 described above, so that the flat plate-shaped upper end portion 4a can be releasably abutted against the lower surface of the pressure sensitive plate 5 through the flat plate-shaped upper end portion 4a. is there.

In addition, the above-mentioned weak spring 70 linked to the valve 60 for the relief valve is
The spring pressure is set to an extremely weak one tenth to several tenths of the spring pressure of the pressure reducing spring 2a.

The embodiment apparatus configured as described above operates as follows.

When the pressure on the secondary side Y side, that is, the pressure in the pressure-sensitive chamber W is F1 and the spring pressure of the spring 70 linked to the relief valve 60 is F2. , F1−F2, the pressure sensing plate 5 is pushed downward by the spring pressure of the pressure reducing spring 2a, resulting in the state shown in FIG.

In this state, the relief valve 60 hits the relief valve valve seat 62 and pushes up the valve rod 3 with the spring pressure of the spring 70 linked thereto, so that the valve rod 3 is connected to the rod 4. In this state, the pressure sensitive plate 5 is integrally connected, and in this state, the pressure in the pressure sensitive chamber W decreases, so that the pressure sensing plate is pressed against the relief valve valve seat 62 while the relief valve valve 60 is pressed against the relief valve valve seat 62. 5, the rod 4, the valve rod 3, and the pressure reducing valve 20 attached thereto move integrally, and the opening degree between the pressure reducing valve 20 and the pressure reducing valve seat 21 is expanded or reduced to increase the pressure on the secondary side Y. It acts to keep it constant.

Next, when the pressure on the secondary side Y becomes larger than the value of F1-A2, the pressure reducing valve 20 comes into pressure contact with the pressure reducing valve seat 21 and the state shown in FIG. 1 is reached. Abnormally increased, F1
When it becomes larger than the value of + F2, as shown in Fig. 3, the pressure reducing valve 20
The pressure-sensitive plate 5 and the rod 4 rise while leaving the pressure reducing valve seat 2 in an abutting position, whereby the relief valve 60 is pulled up and the relief valve 6 is opened.

Next, FIG. 4 shows another embodiment.

In this embodiment, in addition to the spring 70 that pushes up the valve rod 3, the valve rod 3 is
Another spring 71 is stretched between the lower end of the valve body and the valve box body 1a, and the valve rod 3 is pushed up by the two springs 70, 71. The same components as those of the embodiment shown in the drawings are denoted by the same reference numerals and detailed description thereof will be omitted.

In this embodiment, when the spring pressure of the spring 71 is F3, a predetermined pressure reducing operation is performed when the pressure on the secondary side Y is smaller than the value of F1-F2-F3, and the pressure on the secondary side Y is F1 + F2. When it becomes larger, the relief valve 6 will open,
At this time, F3 is not involved. From this, F2 can be set to an extremely small spring pressure, and the relief valve 6
The valve opening operation of can be sharpened.

Next, FIG. 5 shows another embodiment.

In this embodiment, the relief valve 60 is provided with a manual opening / closing device a which is operated from the outer surface side of the valve box 1 to forcibly open the relief valve 60. The same components as those of the embodiment shown in FIGS. 1 to 3 are denoted by the same reference numerals and detailed description thereof will be omitted.

Then, the manual opening / closing device a has a valve opening at the bottom of the valve body 1a.
A push button-like push rod 9 whose inner end is pushed up by pushing the operation portion 90 projecting to the outer surface of the valve box 1 below the 61 is provided movably up and down. It is configured by abutting the inner end portion against the lower surface of the relief valve 60, and pushes up the relief valve 9 to push up the relief valve 60 against the bias of the spring 70. This acts to open the valve.

Also in the embodiment shown in FIG. 5, the spring 71 used in the embodiment shown in FIG. 4 may be provided as shown by the chain line in FIG.

[Effects of the Invention] As described above, in the pressure reducing / releasing valve according to the present invention, when the pressure higher than the set pressure is generated on the secondary side and the pressure sensitive plate 5 is pushed up, the pressure sensitive plate 5, the rod 4, and the spring. The pressure reducing valve 20 connected via 70 is pulled up and closed to cut off the communication with the primary side X, and then,
This pressure reducing valve 20 is left in the closed position, and the pressure sensitive plate 5 and the rod 4 are
Rise and the relief valve 60 is pulled up and the relief valve valve opening 61
Is opened to release the pressure on the secondary side to the outside, and the relief valve 6 provided to release the abnormal pressure generated on the secondary side to the outside in the valve box 1 performs the pressure reducing operation on the pressure reducing valve 20. Since the opening / closing control is performed by the operation of the pressure sensitive plate 5 having a wide pressure receiving area, the sensitivity of the relief valve 6 becomes extremely sensitive.
Therefore, the abnormal pressure generated on the secondary side does not interfere with the predetermined pressure reducing operation by the pressure reducing valve, and the pressure on the secondary side is further increased with reference to the set pressure set by the pressure reducing valve. When the pressure rises, it becomes possible to obtain a pressure reducing / releasing valve that can detect it with high sensitivity and release it correctly / quickly to the outside.

[Brief description of drawings]

FIG. 1 is a vertical sectional front view of a pressure reducing / releasing valve according to the present invention,
2 and 3 are explanatory views of the same operation, FIG. 4 is a vertical sectional front view of another embodiment, and FIG. 5 is a vertical sectional front view of a different embodiment. Explanation of drawing symbols A: Pressure reducing / releasing valve, a: Manual opening / closing device S: Stopper, W: Pressure sensing chamber X: Primary side, Y: Secondary side F1, F2, F3 ... Spring pressure 1 …… Valve box 1a …… Valve box main body, 1b …… Spring case 10 ・ 11 …… Connection pipe, 12 …… Differential partition 13 …… Cylindrical part, 14 …… Connection pipe 20 …… Decompression valve, 2a… … Decompression spring 21 …… Decompression valve seat, 3 …… Valve rod 3a …… End face, 30 …… Piston 4 …… Rod, 4a …… End 4b …… Screw, 4c …… Tightening net 5 …… Pressure-sensitive plate, 6 ... Relief valve 60 ... Relief valve valve 61 ... Relief valve valve opening, 62 ... Annular valve seat 70/71 ... Spring, 80 ... Adjusting screw 9 ... Push rod , 90 …… Operation part

Claims (1)

[Claims] 1. A lower end of a valve rod 3 provided with a pressure reducing valve 20 provided in a valve box 1 for controlling opening and closing of communication between a primary side X and a secondary side Y, and a balancing piston 30 provided on an upper end side. Connect the sides,
A rod 4 penetrating vertically is slidably inserted into the axial center portion of the valve rod 3, and the upper end side of the rod 4 is connected to a pressure sensitive plate 5 that operates by sensing a secondary pressure. The relief valve 60 is provided at the lower end portion protruding downward from the pressure reducing valve 20.
Is provided slidably in the longitudinal direction of the rod 4 and a stopper S for restricting the downward movement of the relief valve 60 with respect to the rod 4 to a predetermined position is provided. A spring 70 for pushing the valve S toward the stopper S is connected to the valve 60, and a valve opening 61 for the relief valve that is opened and closed by the valve 60 for the relief valve is provided at the bottom of the valve box 1 so as to be opened to the outside, and the valve rod is provided. A pressure reducing / releasing valve that is abutted against the lower surface of the pressure sensitive plate 5 on the upper end side of 3 so as to freely come into contact with and come into contact with it.