JP2559821Y2 - Cap nut with detection piston for container valve - Google Patents

Description

[Detailed description of the invention]

[0001]

The present invention relates to a cap nut which is screwed into a gas outlet (gas filling port) of a high-pressure gas container valve in a gas-tight manner, wherein a detection piston is provided on an inner surface of a top plate of the cap nut. The present invention relates to a cap nut with a detection piston of a container valve, which can detect gas leakage in a gas outlet passage at a glance by projecting an outer surface of a top plate of a piston rod of the detection piston.

[0002]

2. Description of the Related Art Conventionally, in a valve for a high-pressure gas container, after filling or using the gas, the valve is closed with a handle or the like, and a cap nut (cap nut) is provided at a gas outlet (gas filling port) (FIGS. 4 and 5). ) Is hermetically screwed in air-tight.

[0003] This is to serve as a double safety valve when gas leaks from the valve for some reason during subsequent storage or transportation of the gas container, and a gas outlet in which the valve and the cap nut are screwed. Therefore, even if gas leaks into the gas outlet passage between them, the gas is not leaked to the outside by the cap nut, so that it is safe for the time being.

However, recently, demands for various chemical special gases (so-called semi-material gases) used particularly in semiconductor manufacturing processes are rapidly increasing, and such special gases are used at high pressure. It is extremely expensive and very dangerous, such as radioactive gas, fire, for example, if it comes into contact with air, or the lethal amount of comma PPM, etc. More and more.

Therefore, even if the gas used for filling the container is
In the case of conventional LPG, Freon gas, carbon dioxide gas, etc., if gas leaks from the valve and accumulates in the gas outlet passage between the cap nut and the cap nut, if it does not leak out, it is sufficiently safe. Nature is secured,

In the case of the above-mentioned special gas, even if the external leakage can be prevented by the cap nut, the existence of a trace amount of gas remaining in the gas outlet passage between the cap nut and the valve poses a serious problem. It becomes.

That is, if the cap nut is removed to fill the gas or use the gas without knowing that there is a trace amount of gas leaking into the gas outlet passage, the special gas flows out and the operator This is because there is a great danger of causing personal injury, fire, explosion, and environmental pollution due to radioactive materials. Even if a gas leak of the valve is noticed and the valve is re-tightened, the above danger does not change at all if gas is already accumulated in the gas outlet passage.

[0008]

Therefore, it is necessary to surely know from the outside that a gas leak has occurred in the gas outlet passage by some method. The present invention has solved the above-mentioned problems by a cap nut with a detection piston of the present invention.

That is, a valve is constituted by contacting a valve stem with a valve seat formed between a gas inlet passage and a gas outlet passage in a valve body, and the valve stem is moved up and down by operating a handle or the like to open and close the valve. In a cap nut that tightly covers the gas outlet of a high-pressure gas container valve, the detection piston is slid on the inner surface of the top plate of the cap nut by the rising internal pressure in the outlet passage due to gas leakage from the valve. A piston for detecting the leakage of gas into the gas outlet passage by projecting the piston rod so that the tip of the piston rod projects to the outer surface of the top plate. The above problem has been solved by an attached cap nut.

[0010]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.

A valve stem 4 is brought into contact with a valve seat 3 formed between a gas inlet passage 2a and a gas outlet passage 2b in the valve body 1 to constitute a valve 5. The valve stem 4 is moved up and down by operating a handle 6 or the like. Move and valve 5
In the cap nut 7 that hermetically covers the gas outlet 2b 'of the high-pressure gas container valve A that opens and closes,

A detection piston 9 is provided on the inner surface of the top plate 8 of the cap nut 7, and a gas outlet passage 2b caused by gas leakage from the valve 5.
The piston rod 9a is slid by the rising internal pressure so that the tip of the piston rod 9a protrudes from the outer surface of the top plate 8.
A cap nut 7a with a detection piston of a container valve is provided so as to detect gas leakage into the gas outlet passage 2b by the protrusion of a.

The detection piston 9 is slidably and airtightly inserted through an O-ring 11 into a cylinder 10 protruding from the inner surface of the top plate 8.
It is provided so as to protrude to the outside through the small hole 12 (usually flush with the top plate 8).

If necessary, a spring for returning the detection piston 9 to its original position after releasing the rising internal pressure in the gas outlet passage 2b is elastically provided between the top plate 8 and the detection piston 9 in the cylinder 10. I do. (Not shown)

It is necessary that the tip of the piston rod 9a projecting to the outer surface of the top plate due to gas leakage into the gas outlet passage 2b be clearly visually detected from the outside. Therefore, the tip of the piston rod 9a is colored in red or the like so as to be conspicuous, or a seal is stuck on the outer surface of the top plate so that the piston rod 9a can be immediately detected when the seal is broken by the protrusion of the piston rod 9a. Take.

[0016]

After the gas is filled and used, the valve is closed, and the kip nut 7a with the detection piston is screwed into the gas outlet 2b '. When gas leaks out of the valve 5 and accumulates in the gas outlet passage 2b due to a cause, the internal pressure in the passage 2b increases, and the detection piston 9 pressed by the increased internal pressure slides in the cylinder 10, and The tip of the piston rod 9a projects outside from the small hole 12 of the top plate 8.

Therefore, the worker or the like can use the piston rod 9a projecting from the outer surface of the top plate of the cap nut 7a with the detection piston.
By visually detecting the tip, it is possible to immediately know that there is gas leakage.

The container which has detected the gas leakage is treated by a safe means such as a collection by a professional worker or a factory.

Therefore, the operator can check the presence or absence of gas leakage from the container by the simplest and most reliable visual inspection.
Work safety can be expected.

Means that make the end of the piston rod protruding to the outside of the top plate red or other color, or that a sticker is attached to the outer surface of the top plate so that the piston rod penetrates through the seal, etc. By taking this measure, the effect of visual detection can be further improved.

Since the cylinder housing the detection piston protrudes from the inside of the top plate, the volume of the space in the gas outlet passage 2b can be reduced by that much as compared with the prior art, so that the gas leaks out and is stored there. Gas volume can be reduced. Further, unlike the case where the cylinder is protruded from the outer surface of the hand plate, there is also an effect that it does not hinder the fitting of the valve cover cap 14 of the container 13.

If necessary, a spring for restoring the detection piston is interposed between the detection piston in the cylinder and the top plate, so that when the cap nut with the detection piston is reused, the detection piston that has slid and protruded one by one must be manually operated. There is an advantage that the trouble of restoring is unnecessary.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional front view of a high-pressure gas container valve in which a cap nut with a detection piston is screwed to a gas outlet according to an embodiment of the present invention.

FIG. 2 is a longitudinal sectional front view of a cap nut with a detection piston according to the embodiment of the present invention;

FIG. 3 is a plan view of FIG. 2;

FIG. 4 is a longitudinal sectional front view of a conventional cap nut.

FIG. 5 is a plan view of FIG. 4;

[Explanation of symbols]

 A container valve 1 valve body 2a gas inlet passage 2b gas outlet passage 2b 'gas outlet 3 valve seat 4 valve stem 5 valve 6 handle 7 cap nut 7a cap nut with detection piston 8 top plate 9 detection piston 9a piston rod 10 cylinder 11 O-ring 12 Small hole 13 High-pressure gas container 14 Valve cover cap 15 Packing

Claims (4)

(57) [Scope of request for utility model registration] A valve is constituted by contacting a valve stem with a valve seat formed between a gas inlet passage and a gas outlet passage in a valve body, and the valve stem is moved up and down by operating a handle or the like to open and close the valve. In the cap nut that seals the gas outlet of the high-pressure gas container valve that is to be performed, the detection piston is mounted on the inner surface of the top plate of the cap nut, and the rising internal pressure in the gas outlet passage due to gas leakage from the valve The piston rod is slid so that the tip thereof protrudes to the outer surface of the top plate, and gas leakage into the gas outlet passage is externally detected by the protrusion of the piston rod,
Cap nut with detection piston for container valve. 2. A cap nut with a detection piston for a container valve according to claim 1, wherein a detection piston is provided in an airtight and slidable manner via an O-ring in a cylinder protruding from an inner surface of the top plate. 3. The container valve according to claim 1, wherein a spring for returning the detecting piston to its original position after the rising internal pressure in the gas outlet passage is released is elastically provided between the top plate and the detecting piston in the cylinder. Cap nut with detection piston. 4. The container according to claim 1, wherein the tip of the piston rod protruding from the outer surface of the top plate is clearly visually detected by coloring the tip of the piston rod or attaching a seal to the outer surface of the top plate. Nut with detection piston for valve.