JPH0726614Y2 - Coil spring lift type quick closing check valve - Google Patents

Description

[Detailed description of the device]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coil spring lift type quick-close check valve in which a valve body is pressed against a valve seat by a coil spring attached to the valve body via a spring retainer.

[0002]

2. Description of the Related Art An example of a conventional coil spring lift type quick-close check valve is shown in FIG. The valve body 3 is seated on the valve seat 2 mounted in the casing 1,
The valve body 3 is integrated with the valve rod 4 and is urged toward the valve seat 2 by a spring 5. The spring 5 is held by the spring retainer 6 in such a manner that the spring 5 can exert its elastic repulsive force.

A coil spring lift type quick-close check valve having a configuration as shown in FIG. 4 should be used in a vertically installed state (as shown in FIG. 4) in principle. Horizontal (Fig. 4
When it is mounted in a state in which the valve body 3 and the valve rod 4 are rotated by 90 degrees, the smooth operation of the movable body composed of the valve body 3 and the valve rod 4 is hindered. If the valve is small, there will be no problem in a short period of time, but if the valve is large or used for a long period of time, the operation of the movable body will be adversely affected. Therefore, as shown in FIG. 5, a coil spring lift type quick-close check valve having a structure in which a movable body (a member composed of a valve body and a valve rod) is supported at both ends of the valve rod has been proposed.

In FIG. 5, members having the same function are designated by the same reference numerals as those in FIG. The coil spring lift type quick closing check valve of FIG. 5 is provided with a guide portion 8 supported by a rib on the valve seat 2. Since the valve rod 4 is supported not only by its upper end but also by its lower end and its vicinity by the guide portion 8, it is movable even when a large valve is installed horizontally for a long period of time. It does not hinder the smooth operation of the body.

Here, a male screw portion 9 is formed on the outer peripheral surface of the valve seat 2 around the rib, and the male screw portion 9 is screwed into a female screw portion 10 of the casing 1. And valve seat 2
A convex portion 11 is formed above the male screw portion 9 of the
1 is fitted or abutted on the shoulder 121 of the casing 1.

[0006]

In a conventional coil spring lift type quick closing check valve as shown in FIG. 5, a valve seat 2 is provided.
It is necessary to prevent the working fluid from leaking from the connecting portion between the casing 1 and the casing 1 (the fitting portion between the convex portion 11 and the shoulder portion 12 and the screwing portion between the male screw portion 9 and the female screw portion 10). Therefore, a sealing agent is applied to the threaded portion between the male screw portion 9 and the female screw portion 10, or a gasket GS (FIG. 6) is interposed on the lower surface of the fitting portion between the convex portion 11 and the shoulder portion 12, The leak of working fluid is prevented.

However, with such a method, it is impossible to completely prevent loosening of the screwed portion between the male screw portion 9 and the female screw portion 10. Further, leakage of the working fluid due to damage to the gasket GS itself cannot be avoided.

The present invention has been proposed in view of the problems of the prior art as described above, and a coil spring lift type quick-close check valve capable of preventing the leakage of the working fluid from the connecting portion between the valve seat and the casing. The purpose is to provide.

[0009]

A coil spring lift type quick-close check valve of the present invention is a coil spring lift in which a valve body is pressed and urged against a valve seat by a coil spring attached to the valve body via a spring retainer. In the quick-closing check valve, in order to configure a mechanism for preventing fluid leakage from between the valve seat and the casing, a protrusion is formed at the portion of the valve seat that abuts the shoulder of the casing.

Here, it is preferable that the protrusion is a sharp protrusion. However, it is not necessary that the projection is a sharp one as long as it is in contact with the lower surface of the casing shoulder portion and is easily deformed by compression.

In the coil spring lift type quick check valve according to the present invention, a female screw portion is formed at a portion of the casing where the valve seat is attached, and a male screw portion which is screwed with the female screw portion is formed on the outer peripheral surface of the valve seat. It is provided with a mechanism for tightening a set screw from the outside of the casing to prevent the valve seat from being screwed.

In the practice of the present invention, the valve seat of the coil spring lift type quick-close check valve has a guide portion for guiding the valve rod supported by a plurality of ribs, and the ribs and the guide portion are integrated with the valve seat. It is preferably configured in a general manner.

[0013]

According to the coil spring lift type quick-close check valve of the present invention having the above-mentioned structure, when the valve seat is attached to the casing, the protrusion formed at the portion of the valve seat that abuts the casing is formed. It comes into contact with the shoulder portion of the casing and is compressed and deformed into a crushed state. As a result, the valve seat portion where the protrusion is formed and the shoulder portion of the casing come into close contact with each other, and a sealing mechanism is formed without a gasket.

Also, by providing a mechanism for tightening a set screw from the outside of the casing to prevent loosening of the screwing of the valve seat, the loosening of the screwing portion of the male screw portion of the valve seat and the female screw portion of the casing is prevented. Be seen. This prevents the working fluid from leaking due to loosening of the screwed portion.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. The same members as those in FIGS. 4 to 6 will be described with the same reference numerals.

In FIG. 1, a coil spring lift type quick-close check valve according to the present invention, which is generally designated by the reference numeral 20, has a valve seat 2 housed in a casing 1, with respect to the valve seat 2. The valve body 3 is seated. This valve body 3 is a valve stem nut 2
It is integrally connected to the valve rod 4 by 2 and is pressed and urged by the spring 5 via the valve rod gasket 24. Further, the spring 5 is held at a predetermined position in the casing 1 by the spring retainer 6.

The valve seat 2 includes a valve seat disc 26, which is
Includes a plurality of ribs 30 arranged at equal intervals and a guide portion 8 supported by the ribs. And valve seat 2
Is in contact with or fitted to the shoulder 12 of the casing 1,
Moreover, a male screw portion 9 is formed on the outer peripheral surface thereof. The male screw portion 9 is screwed with a female screw portion 10 formed at the valve seat mounting portion of the casing 1. The location where the valve seat 2 abuts the shoulder 12 of the casing 1 is shown in FIG.
It will be described later with reference to FIG.

In FIG. 1, reference numeral 32 is a set screw for preventing loosening of the screw engagement between the male screw portion 9 and the female screw portion 10, and reference numeral 34 is a plug for accommodating the set screw. Reference numeral 36 indicates a bypass valve.

Next, referring to FIGS. 2 and 3, the valve seat 2
Will be described in more detail.

The upper end surface 2S of the valve seat 2 is a valve seat surface on which the valve element 3 (not shown in FIGS. 2 and 3) is seated. The lower end surface 26S of the valve seat base 26 has a projection 40 formed relatively sharply. The protrusion 40 may be a large number of protrusions arranged in the circumferential direction, or may be a single annular protrusion.

When assembling the valve seat 2 to the casing 1, first, the male screw portion 9 of the valve seat 2 is screwed with the female screw portion 10 of the casing 1 where the valve seat is attached. As a result of the screwing, the protrusion 40 formed on the lower end surface 26S of the valve seat base 26 comes into contact with the shoulder 12 of the casing 1, and when further screwed, the protrusion 40 comes into contact with the lower surface of the shoulder 12. Then, it is compressed and deformed to be crushed, and the lower end surface 26S of the valve seat base 26 and the shoulder portion of the casing are brought into close contact with each other. As a result, the sealing mechanism is formed without interposing the gasket.

When the male screw portion 9 and the female screw portion 10 are screwed together, as shown in FIG. 1, the male screw portion 9, that is, the valve seat 2 is pressed by the set screw 32 to prevent the screwing portion from loosening, and the plug is plugged. The set screw 32 may be fixed with 34.

[0023]

The effects of the present invention are listed below.

(1) It is possible to prevent the working fluid from leaking from the joint portion between the valve seat and the casing without interposing a gasket.

(2) By preventing the loosening, leakage from the screw threaded portion can be suppressed.

(3) The smooth operation of the movable body composed of the valve body and the valve rod is guaranteed.

(4) Rattling caused by loosening of the screw-threaded portion is prevented.

(5) Since the leakage of the working fluid can be prevented,
The reliability of the valve itself is improved.

(6) Since it is unnecessary to insert a gasket and apply a sealant, the manufacturing cost is reduced.

(7) The number of parts is reduced and the assembling work is facilitated.

[Brief description of drawings]

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

2 is a sectional front view of a valve seat used in the embodiment of FIG.

FIG. 3 is a plan view showing the valve seat used in the embodiment of FIG. 1 partially broken away.

FIG. 4 is a sectional front view of a conventional technique.

FIG. 5 is a sectional front view showing another conventional technique.

FIG. 6 is a partially enlarged view of the conventional technique of FIG.

[Explanation of symbols]

 1 ... Casing 2 ... Valve seat 2S ... Valve seat surface 3 ... Valve body 4 ... Valve rod 5 ... Spring 6 ... Spring retainer 9 ... Male screw part 10 ... -Female screw portion 12 ... Casing shoulder portion 20 ... Coil spring lift type quick-close check valve 26 ... Valve seat base 32 ... Set screw 34 ... Set screw plug 40 ... Protrusion Department

Claims (2)

[Scope of utility model registration request] 1. A coil spring lift type quick closing check valve in which a valve body is pressed and urged against a valve seat by a coil spring attached to the valve body via a spring retainer,
In order to configure a mechanism for preventing fluid leakage between the valve seat and the casing, a protrusion is formed at the valve seat where it abuts the shoulder of the casing. Stop valve. 2. A female threaded portion is formed at a location where the valve seat is attached to the casing, and a male threaded portion which is screwed with the female threaded portion is formed on the outer peripheral surface of the valve seat. The coil spring lift type quick-close check valve according to claim 1, further comprising a mechanism for preventing loosening of the screw engagement.