JPH11311345A - Safety valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simplify the working while securing the air-tightness at the time of operation by arranging a ring-like seal member to be inserted between a valve element and a vale seat so as to secure the air-tightness in a space formed by a ring-like auxiliary member for surrounding the periphery of the valve element and the valve seat with the inner peripheral wall thereof, the valve element and the valve seat without fixing it. SOLUTION: Fastening condition of an adjustment screw 9 is adjusted so as to move a spring receiver 6', and compressing condition of a spring 7 is changed so as to adjust the energizing force. A valve rod 5 is pushed downward by the energizing force of the spring 7 through the spring receiver 6 so that the valve element 4 contacts with an O-ring 2 provided on a valve seat 16 of a main body 1 for seal. The 0-ring 2 is arranged without fixing it in a blow- out part as a space formed by the main body 1, the valve element 4 and a spring body 8 inside of a ring-like auxiliary ring 3 arranged so as to surround a side wall of a part of the valve seat of the main body 1 and the valve element 4. With this structure, reliability, safety and maintenance are improved, and a manufacturing process and a working process of a safety valve can be simplified.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a safety valve and, more particularly, to an airtight structure of a safety valve for improving airtightness of a seat portion and simplifying processing.

[0002]

2. Description of the Related Art A safety valve for protecting equipment such as a hydraulic circuit or a pipe from destruction needs to maintain a high degree of airtightness. The airtightness has been improved by using a synthetic resin or the like.

FIG. 3 shows some examples of a conventional airtight (seal) structure of a safety valve. In the structure shown in FIG. 3A, an annular groove is provided in a valve seat portion of the main body 1 in contact with the valve body 4,
The O-ring 2 is fitted in the groove. FIG.
In the structure shown in (b), an annular groove is provided on the valve body side that comes into contact with the valve seat of the main body 1, and the O-ring 2 is fitted into the groove. Next, a structure (c) shown in FIG. 3 is one in which an O-ring 2 is fitted into a groove of a tapered portion that comes into contact with the main body 1 in a valve body having a tapered vertical cross section. Further, FIG.
The structure shown in (d) is a diagram showing a configuration in which an annular groove is provided in a valve body seat portion that contacts the valve seat portion of the main body 1 and a ring-shaped sealing material is fitted into the groove.

[0004]

However, when an O-ring or a ring-shaped sealing member made of synthetic resin or the like is used, the self-pressure becomes a back pressure on the back side of the ring when the safety valve is operated, and the ring moves from the groove. There is a problem that it may jump out. That is, at the time of opening,
When the safety valve operates, the valve body 4 that has been in contact with the main body valve seat is separated from the main body valve seat by the pressure of the nozzle portion that is the primary chamber,
From the gap, the flow rate of the primary chamber is discharged from the discharge port through the secondary chamber, and sets the upper limit of the pressure of the primary chamber.
At that time, the secondary chamber side becomes back pressure (negative pressure), and the O-ring fitted in the groove of the valve body or the like jumps out from the open end side of the groove.

For this reason, the conventional safety valve can be used in the case where a very small amount of flow is discharged while the valve body is slightly separated from the main body, but it is possible to avoid the destruction of the equipment due to a sudden increase in pressure or the like. It is not suitable for satisfying the flow rate as a safety valve.

That is, in a safety valve in which a sudden change in pressure occurs, in the above-described hermetic structure, the O-ring pops out when the safety valve operates, and when the valve is closed again after the pressure control is completed, the O-ring Is not in a state where the groove is fitted, and can no longer be airtight, and cannot be used as a safety valve. And maintenance work is always required.

SUMMARY OF THE INVENTION Accordingly, the present invention has been made in view of the above problems, and an object of the present invention is to provide a safety valve having a structure that ensures airtightness during operation, simplifies machining, and facilitates maintenance. To provide.

[0008]

In order to achieve the above object, the present invention provides a ring type sealing member such as an O-ring inserted between a valve body and a valve seat for ensuring airtightness. A ring-shaped auxiliary member that surrounds the outer periphery of the valve seat with its inner wall, and is disposed without being fixed in a space defined by the valve body and the valve seat.

[0009]

Embodiments of the present invention will be described below. In a preferred embodiment of the safety valve according to the present invention, referring to FIG. 1, a valve body (1) screwed and fixed to a pipe or the like, a valve body (4), and a spring or the like from one side. And a valve rod (5) pressed by the biasing force of the elastic member (7). The valve body (1) penetrates the valve body from the mounting side and opens to the valve seat (16) end face side. A safety valve having a configuration in which a primary chamber (nozzle portion) (13) is provided, and when the valve is opened, the fluid in the primary chamber is guided to the secondary chamber from a gap between the valve body and the valve seat and discharged from the discharge port. A ring-shaped auxiliary member (3) is provided so as to surround a part of the outer periphery of the valve seat and the outer periphery of the valve body in the height direction, and an air-tight O-ring or seal member (2) is provided. On the valve seat, the auxiliary member inner wall, and freely disposed without being fixed in the space defined by the valve body It is intended.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a longitudinal sectional view showing the entire configuration of a safety valve according to one embodiment of the present invention, and FIG. 2 is an enlarged view of a main part of FIG.

1 and 2, reference numeral 1 denotes a valve body, which has a nozzle portion 13 opened in the center.
A thread groove for screwing to a device to be pressure-controlled, such as a pipe or a pump through which fluid is pumped, is provided on the outer periphery. 2 is an O-ring for airtightness, 3 is an auxiliary wheel, 4 is a valve body, 5 is a valve stem, 6 is a spring receiver, 7 is a spring (spring), 8 is a spring box, 9 is an adjusting screw, 10 is a lock nut, 11 is a cap and 12 is a bolt.

By adjusting the degree of tightening of the adjusting screw 9,
The spring receiver 6 'moves in the vertical direction in the figure, and the degree of compression of the spring 7 is varied to adjust the urging force. The urging force of the spring 7 causes the valve shaft (shaft) 5 to move through the spring receiver 6 as shown in FIG. , The valve body 4 comes into contact with the O-ring 2 on the valve seat 16 of the main body 1 to be airtight.

The airtight O-ring 2 is not fixed as in the conventional structure shown in FIG. 3, but is freely disposed inside the auxiliary wheel 3. That is, the main body 1 and the valve body 4
And in the blowing part 14 which is a space defined by the spring box 8,
The O-ring 2 is freely disposed in a state where the O-ring 2 is not fixed inside the ring-shaped auxiliary wheel 3 disposed so as to surround the valve seat portion of the main body 1 and a part of the side wall of the valve element 4. .

When operating as a safety valve, the pressure of the nozzle portion 13, which is the primary chamber, rises and pushes the valve body 4 upward in the drawing against the urging force of the spring 7, and the fluid from the nozzle portion 13 It flows out to the blowing part 14 through the gap 4 (flow path) between the body 4 and the auxiliary wheel 3 and is discharged from the discharge port 15. that time,
Pressure acts on the entire O-ring 2 so that it is not pushed in one direction.

That is, when the valve element 4 rises when the safety valve is operated, the O-ring 2 is disposed below the valve seat 16 of the main body 1 due to the outflow (pressure) of the fluid from the nozzle portion 13 to the blowing portion 14. The outer peripheral side wall performs the vertical movement in the space defined by the valve body 4 according to the flux, while the upper side performs the vertical movement in the space defined by the valve body 4. The valve body 4 is in contact with the valve seat 16 via the O-ring 2 to maintain airtightness. The auxiliary wheel 3 is, for example, a valve seat 16 of the main body 1.
It is fixed by attaching it to the like. The fixing method is not limited to screwing, fastening with bolts, etc., as long as a flow path from the nozzle portion 13 to the blowing portion 14 is provided.

According to this embodiment, as shown in FIG.
There is no need to provide a groove for arranging an O-ring in the valve body or valve seat, which simplifies the manufacturing and processing steps of the safety valve. Further, according to the present embodiment, when the safety valve is activated, O
Since the problem that the ring protrudes and the safety valve becomes unusable is avoided, maintenance is particularly facilitated.

[0017]

As described above, according to the present invention,
The airtight O-ring or the sealing member does not fly out during operation, thereby improving reliability and safety, improving maintainability, and simplifying the manufacturing process and processing process of the safety valve.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing an overall configuration of an embodiment of the present invention.

FIG. 2 is a sectional view showing a main part of one embodiment of the present invention.

FIG. 3 is a view for explaining a conventional airtight mechanism of a safety valve.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Valve main body 2 O-ring 3 Auxiliary wheel 4 Valve body 5 Valve rod (shaft) 6, 6 'Spring receiver 7 Spring 8 Spring box (case) 9 Adjusting screw 10 Lock nut 11 Cap 12 Bolt 13 Nozzle part 14 Blow-out part 15 Release Exit 16 valve seat

Claims (3)

[Claims] A ring-type sealing member inserted between a valve body and a valve seat for ensuring airtightness; a ring-type auxiliary member surrounding an outer periphery of the valve body and the valve seat with an inner wall thereof; A safety valve characterized by being freely disposed without being fixed in a space defined by a body and a valve seat. 2. An O-ring inserted between the valve body and the valve seat for ensuring airtightness, a ring-type auxiliary member surrounding the outer circumference of the valve body and the valve seat with its inner wall, A safety valve characterized by being freely disposed without being fixed in a space defined by a valve seat. 3. A valve body which is screwed and fixed to a pipe or the like, a valve body, and a valve stem which presses the valve body from one side by an urging force of an elastic member. A primary chamber is provided which penetrates a valve body and opens on the valve seat end face side facing the valve element, and when the valve is opened, a fluid from the primary chamber side is provided between the valve element and the valve seat. A safety valve that is guided to a secondary chamber through a discharge port as a flow path, and is disposed in the secondary chamber so that a part of the valve seat and the valve body outer peripheral side wall in a height direction is surrounded by an inner wall thereof. A ring-shaped auxiliary member is provided, and an air-tight O-ring or a seal member is disposed on the valve seat without being fixed in a space defined by the auxiliary member inner wall and the valve body. Characterized by a safety valve.