JPH0736550A - Pressure reducing valve - Google Patents

Abstract

PURPOSE:To prevent the deterioration and the breakage of the diaphragm of a pressure reducing diaphragm valve caused by the excess tension due to the high fluid pressure applied to the diaphragm and also to set the valve body on the valve sent with no biting. CONSTITUTION:A stopper 29 prevents a diaphragm 21 which senses the secondary fluid pressure from being displaced toward a control spring 32 by a fixed extent or more. So that the excess tension is not produced to the diaphragm 21. Furthermore a spindle 11 of a valve body 9 is connected to the diaphragm 21 with play secured in the opening/closing operation direction. Then the body 9 is set on a valve seat 3 only by the spring load of a valve opening spring 17.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pressure reducing valve in which a valve element opens and closes in conjunction with a diaphragm for detecting a secondary side fluid pressure, and mainly relates to water supply for individual houses and hot water supply facilities of apartment houses. Used to reduce the pressure of water and hot water.

[0002]

2. Description of the Related Art A secondary side fluid pressure is detected by a diaphragm, and when an imbalance with the opposing spring load of an adjusting spring occurs, the valve body opens and closes according to the displacement of the diaphragm to determine the primary side fluid. A pressure reducing valve for reducing pressure to a secondary fluid of pressure is widely known, and a valve element that blocks / communicates a primary passage and a secondary passage by contacting / separating from a valve seat is connected to a diaphragm by a spindle. The diaphragm chamber formed on the spindle side of the diaphragm communicates with the secondary passage, and the adjusting spring is arranged on the opposite side of the diaphragm.

When such a pressure reducing valve is incorporated into a pipe and a pipe pressure resistance test is performed, in a structure in which the valve body and the diaphragm are integrally connected by a spindle, the pressure applied to the primary side during use is adjusted. The primary side fluid pressure exceeding the set pressure is introduced into the pressure reducing valve that is applied to the diaphragm as it is, generating a strong valve closing force and pressing the valve body strongly against the valve seat load, and the disc part of the valve body to the valve seat. If it is bitten and deformed, the normal pressure reducing function may be hindered or the disc may be damaged. Further, if the primary fluid may leak into the diaphragm chamber during service, the disc portion of the valve body may be bitten into the valve seat.

As described above, when a fluid pressure significantly exceeding the secondary side adjusting pressure range in service is introduced into the diaphragm chamber, JP-B-46-5754 and JP-A-48-92.
No. 3, gazette of Japanese Utility Model Application Laid-Open No. 2-35207, and the like, which has a structure in which the spindle fixed to the valve body is not integrally connected to the diaphragm,
Even if the diaphragm is largely displaced, the valve body is not pulled by the diaphragm and is closed only by the load of the valve closing spring, so that the inconvenience that the disc portion bites into the valve seat is avoided.

However, since the diaphragm is displaced without limitation until the fluid pressure in the diaphragm chamber and the spring load of the adjusting spring reach a balanced position, as described above, the secondary side adjusting pressure range when in use When a fluid pressure exceeding a large value is introduced, the adjusting spring is compressed and largely displaced, which may cause excessive pulling, resulting in deterioration or damage.

When the fluid pressure in the diaphragm chamber rises and the diaphragm is displaced regardless of whether it is normal or abnormal, the valve element operates in the valve closing direction only by the spring load of the valve closing spring. In order to overcome the static friction force of the sliding parts of the spindle and the spindle to start the valve closing operation, the normal valve closing spring tends to have insufficient load and it is difficult to perform the normal valve closing operation. is there. However, if a valve spring having a large spring load is used as the valve closing spring, the initial valve closing operation can be reliably performed, but this is not suitable in practice because the disk portion may bite when seated on the valve seat. .

[0007]

SUMMARY OF THE INVENTION The problem to be solved by the present invention is that in a diaphragm type pressure reducing valve, when a fluid pressure that greatly exceeds the secondary side adjusting pressure range in service acts on the diaphragm, In the case where the diaphragm and the diaphragm are integrally connected, the disc part of the valve element may dig into the valve seat and interfere with the normal decompression function or be damaged. This is because the diaphragm may be pulled forcibly to cause deterioration or damage, and in addition to this, it is difficult to perform a normal valve closing operation.

[0008]

DISCLOSURE OF THE INVENTION The present invention provides a secondary side fluid pressure of a flow passage formed inside a valve body and a diaphragm on which a control spring for acting against the pressure is applied, and a valve seat provided in the flow passage. A spindle for contacting / separating a valve and a valve-closing spring that acts on the valve in a valve closing direction, and a spindle for interlocking the valve with the displacement of the diaphragm is fixed to the valve and not fixed to the diaphragm. The present invention provides two means for solving the above problems that the pressure reducing valve has.

That is, as a first means, a stopper is provided to prevent the diaphragm from being displaced toward the adjustment spring side beyond a certain level, whereby a fluid pressure that greatly exceeds the secondary side adjustment pressure range in use acts on the diaphragm. Even if it does not cause deterioration or damage.

As a second means, in addition to the first means, the spindle and the diaphragm are connected to each other with a play in the opening / closing direction of the valve body so that the valve is normally closed by following the displacement of the diaphragm. The operation was performed.

In the above two means, it is preferable that the adjusting screw for adjusting the spring load of the adjusting spring is provided with an extension portion to serve as a diaphragm stopper.

[0012]

When the fluid pressure acting on the diaphragm is within the range of the secondary side adjusting pressure during service, the diaphragm is displaced without hitting the stopper and cooperates with the valve closing spring to open and close the valve element. When the fluid pressure acting on the diaphragm greatly exceeds the above pressure range, the diaphragm is prevented from being displaced more than a certain amount by the stopper and is not forcibly pulled, and when the first means is adopted, the valve body closes. The valve load is closed by the spring load of the valve spring.

In the case of the second means, the valve element is operated in the valve closing direction until the diaphragm hits the stopper.
After that, the valve closing spring operates the valve element to seat it on the valve seat, and does not let the disc portion of the valve element bite into the valve seat.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the drawings. A valve seat 3 having a seat surface facing downward is provided at an intermediate portion of a flow passage 2 formed inside a valve body 1 and above the valve seat 3. The primary chamber 5 communicates with the primary passage 6 of the flow path 2 and is the secondary chamber 7 below.
Communicate with the secondary passage 8. A valve body 9 is inserted into the secondary chamber 7, and the valve body 9 is fixed to a spindle 11 extending upward through the valve seat opening 4 and the primary chamber 5, and the spindle 11 is fixed to the primary chamber. 5 and a diaphragm chamber 18 thereabove are connected to each other, and a spindle-shaped guide body 12 which is fitted in a liquid-tight manner is integrally provided in a spindle guide hole 13 formed in the valve body 1. A guide rod 14 formed by extending the spindle 11 below the valve body 9 penetrates the secondary chamber 7 and forms a guide hole 1 in the lower lid body 15 of the valve body 1.
6 is fitted in a liquid-tight manner. Further, the valve body 9 and the lower lid body 1
A valve closing spring 17 composed of a compression coil spring is disposed between the guide rod 5 and the valve 5 concentrically with the guide rod 14.

A spring case 20 is mounted above the valve body 1, and the diaphragm chamber 18 between the lower surface of the diaphragm 21 and the upper surface of the valve body 1, which are fixed by sandwiching the outer peripheral portion thereof, is a secondary passage 8. And a pressure detection path 19 for connection.

A connecting piece 23, which also serves as a nut, is fixed on the lower surface of the central portion of the diaphragm 21 by a bolt 22.
The connecting portion piece 22 is inserted into a connecting hole 25 formed by closing the upper portion of the guide body 12 whose upper portion projects into the diaphragm chamber 18. The connecting piece 23 has an engaging projection 24 on the outer peripheral surface of the intermediate portion, and the connecting hole 25 has a locking projection 26 on the inner peripheral surface of the opening, and the positions at which these protruding portions 24, 26 contact each other. The spindle 11 and the diaphragm 18 can freely move in the opening / closing direction of the valve body 9 between a position where the tip of the connecting piece 22 and the bottom of the connecting hole 25 contact each other. .

An adjusting screw 27 is arranged on the central axis of the spring case 20 so as to pass through the top wall of the spring case 20, and the upper end of the adjusting screw 27 protruding above the spring case 20 is fixed by a lock nut 28. In addition, the downwardly extending portion inside the spring case 20 is extended to a position approaching the head of the bolt 22 of the diaphragm 21 to form a stopper 29.

The spring case 20 is non-circular in plan view and is movable up and down by inscribing an upper spring bearing 30 screwed on the adjusting screw 27. The upper spring bearing 30 and the upper surface of the diaphragm 21 are superposed on each other and the bolt 22 is provided. An adjusting spring 32 formed of a compression coil spring is inserted between the lower spring receiver 31 and the lower spring receiver 31.

In this embodiment having such a configuration, when the secondary side fluid pressure is low, the diaphragm 21 is displaced downward in the drawing by the spring load of the adjusting spring 32, and the connecting piece 23 pushes the guide body 12 to cause the valve body to move. The disk portion 10 of 9 is separated from the valve seat 3 to connect the primary passage 6 and the secondary passage 8 (see A in FIG. 2).

When the secondary fluid pressure increases, the adjusting spring 32
The diaphragm 21 is displaced upward in the drawing by overcoming the spring load of FIG.
Move away from the bottom of 5. Therefore, the valve body 9 is closed by the spring load of the valve closing spring 17, but the guide body 12 of the spindle 11, the spindle guide hole 13, and the guide rod 14 are closed.
When the static frictional force of each sliding portion of the guide hole 16 is large and the valve closing operation cannot be started, the engaging projection 24 engages with the locking projection 26 to push up the guide body 12 to perform the valve closing operation ( See FIG. 2B).

In a normal state where the secondary side fluid pressure acting on the diaphragm 21 is high within the secondary side adjusting pressure range in service, the fluid pressure and the spring load of the adjusting spring 32 are set at a position where the bolt 22 does not contact the stopper 29. Are balanced, the diaphragm 21 stops, and the valve element 9 in the middle of the valve closing operation is closed by the valve closing spring 17
It operates by only the spring load of No. 2 and seats on the valve seat 3 to close the primary passage 6 and the secondary passage 8 (see C in FIG. 2).

When the fluid pressure acting on the diaphragm 21 greatly exceeds the secondary side adjusting pressure range in service, such as when performing a pipe pressure resistance test or when the primary side fluid leaks, the diaphragm 21 is The bolt 22 is stopped at the position where it comes into contact with the stopper 29, and further displacement toward the spring case 20 side is prevented. On the other hand, the valve body 9 is shown in FIG.
After the diaphragm 21 has stopped through the process indicated by B, the valve is further operated only by the spring load of the valve closing spring 17 and seated on the valve seat 3 (see D in FIG. 2).

That is, even if a fluid pressure that greatly exceeds the normal value during use acts on the diaphragm 21, the stopper 29
Since displacement above a certain level is prevented by this, an accident that the diaphragm 21 is forcibly pulled to be deteriorated or damaged is prevented.

Therefore, the structure in which the engaging projection 24 and the locking projection 26 are not provided so that the connecting piece 23 is pushed to the guide body 12 in the valve opening direction but completely free in the valve closing direction is set forth in claim 1. The object of the invention described, namely the protection of the diaphragm, can be achieved.

Further, as in the illustrated embodiment, the diaphragm 2
When 1 starts displacement from the valve opening position in the valve closing direction, the valve body 2
When the engaging projection 24 and the locking projection 26 for carrying 1 are provided, the valve body 21 can be surely closed even if the static friction force is large. In this case, the connecting piece 2
3 and the size of the play between the guide body 12, that is, the engagement protrusion 24
By properly setting the maximum gap between the locking projection 26 and the locking projection 26 in the opening / closing operation direction and the position of the stopper 29, the bolt 2
Even when the diaphragm 21 is displaced until the diaphragm 2 comes into contact with the stopper 29, the valve closing end is operated only by the spring load of the valve closing spring 17 to perform a normal valve closing operation and the disc portion 1
It is possible to achieve the object of the invention described in claim 2 in which 0 is seated without being caught in the valve seat 3.

The stopper 29 is formed by the adjusting screw 27, and the displacement amount of the diaphragm 21 can be adjusted very easily by changing the fixing height to the spring case 20.

The guide body 12 of the spindle 11 and the connecting portion piece 23 of the diaphragm 21 are the same even if the guide body 12 is fitted into the connecting portion piece 23 and connected to each other with play, and the stopper 29 is adjusted. Instead of lengthening and forming the screw 27, for example, a rod-shaped one may be formed so as to project from the tip of the adjusting screw 27.

Next, in the present invention, the displacement of the diaphragm 21 due to the high fluid pressure is limited by the stopper 29, so that the diaphragm 21 pushes the valve body 9 in the valve opening direction, but is completely free in the valve closing direction. In the case of the structure of the invention described in claim 1, the pipe can be built in the pipe from the beginning.

That is, when the piping is completed and initial water is passed to remove and remove residual solid foreign matter, a substitute pipe is inserted into the pipe so as not to be caught by the pressure reducing valve and damage its normal function. Then, after the cleaning is completed, the substitute pipe is removed and the pressure reducing valve is installed, but according to the present invention, such troublesome work can be eliminated.

FIG. 3 shows an example of a forced valve opening mechanism for holding the valve element 9 in the valve opening position at the time of initial water passage, in which the guide rod 14 penetrates the lower lid body 15 and is projected to the outside. The lever 33 is rotatably attached to the protruding end. The guide rod 1 at a position where the lever 33 is rotated by pressing the tip of the lever 33 against the lower surface of the lower lid body 15 to generate no rotational moment.
4 is left on the same axis as 4 to hold the solid foreign matter at the maximum opening position so that solid foreign matter is not caught on the valve body 9 or the valve seat 3. Even if the diaphragm 21 is displaced by the water pressure of the initial water flow, the stopper 1
Since it is not displaced until excessive pulling is caused by 9, the safety of the diaphragm 21 is secured as in the pipe pressure resistance test.

[0031]

As is apparent from the above description, according to the present invention in which the displacement of the diaphragm due to high fluid pressure is limited by the stopper in the structure in which the spindle of the valve body is not fixed to the diaphragm, the diaphragm is largely displaced. It is possible to prevent the accident of being forcibly pulled and deteriorated or damaged, and to accurately detect the secondary side fluid pressure to exert a predetermined pressure reducing function.

In addition to the above, according to the present invention, in which the spindle and the diaphragm are connected by giving a play in the opening / closing direction, the diaphragm operates the valve element in the initial stage of valve closing, and the spring load of the valve closing spring is applied to the valve seat. The valve element is seated only by the valve seat, and the disk portion of the valve element is seated by the normal valve closing operation without digging into the valve seat, and the normal pressure reducing function can be maintained.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of an embodiment of the present invention.

FIG. 2 is an explanatory diagram of an opening / closing operation of the embodiment of FIG.

FIG. 3 is a vertical sectional view of an embodiment of a forced valve opening mechanism.

[Explanation of symbols]

1 valve body, 2 flow passages, 3 valve seats, 6 primary passages, 8 secondary passages, 9 valve bodies, 10 disc parts,
11 spindle, 17 valve closing spring, 21 diaphragm, 23 connecting piece, 24 engaging projection, 2
5 connection holes, 26 locking protrusions, 27 adjusting screws, 2
9 stoppers, 32 adjusting springs,

Continued Front Page (72) Inventor Akihiro Kitagawa 2-21-13 Tamagawa, Ota-ku, Tokyo Ben Corporation (72) Inventor Fumitaka Kato 13-1 Yoshima Industrial Park, Iwaki, Fukushima Ben Iwaki Inside the Technology Center (72) Inventor Minoru Sasaki 13-1 Stock Company, Yoshima Industrial Park, Iwaki City, Fukushima Ben In the Iwaki Technology Center (72) Inventor Takashi Kitada 13-1 Stock Company, Iwaki City, Fukushima Prefecture Ben Iwaki Technical Center

Claims (3)

[Claims] 1. A diaphragm on which a secondary side fluid pressure of a flow passage formed inside a valve main body and an adjusting spring that opposes the fluid pressure act, and a valve element which comes into contact with and separates from a valve seat provided in the flow passage. A pressure-reducing valve having a valve closing spring acting on the valve element in a valve closing direction, wherein a spindle for interlocking the valve element with the displacement of the diaphragm is fixed to the valve element and not fixed to the diaphragm. A pressure reducing valve comprising a stopper for preventing a certain amount of displacement toward the adjustment spring side. 2. A diaphragm on which a secondary side fluid pressure of a flow passage formed inside the valve main body and an adjusting spring that counteracts the pressure is applied, and a valve body which comes into contact with and separates from a valve seat provided in the flow passage. A pressure-reducing valve having a valve closing spring acting on the valve element in a valve closing direction, wherein a spindle for interlocking the valve element with the displacement of the diaphragm is fixed to the valve element and not fixed to the diaphragm. A stopper is provided to prevent a certain amount of displacement toward the adjustment spring side,
The valve and the valve are characterized in that the spindle and the diaphragm are connected to each other with a play in the opening / closing direction of the valve body. 3. The pressure reducing valve according to claim 1, wherein the adjusting screw for adjusting the spring load of the adjusting spring has an extension extending until it approaches the diaphragm, and the extension is a stopper.