JPS5821959Y2 - Cylinder valve with cassette type automatic residual pressure valve - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a cylinder valve that incorporates a residual pressure valve that prevents outside air from entering an empty cylinder, and there is no need to add a pressure reducing valve or a joint.

The purpose is to provide a gas cylinder with a simple structure, easy to find a malfunctioning part, easy replacement and repair, and easy and accurate filling of gas into a cylinder.

Conventional pulp cylinders consisted of only a main valve, so if the main valve was left open after the cylinder was emptied, impurities such as outside air, dust, water, or oil could enter the cylinder. However, this contaminates the newly filled gas and causes a decrease in the purity of the gas.

In order to eliminate this drop in gas purity, it is necessary to wash empty cylinders collected from customers with water and dry them, and then perform gas replacement or vacuuming to expel impure gas (mixed air, etc.) inside the cylinder. The drawback is that it requires a lot of time, effort, and equipment.

In order to eliminate these drawbacks, the inventor of the present invention installed a residual pressure valve inside the gas outlet hole of the cylinder pulp, which automatically shuts off the gas expansion path when the pressure inside the cylinder drops below a certain value. Patent application 1978-8947) was first proposed (
(See FIG. 4A) However, this method has a primary drawback because the residual pressure valve is installed in the gas outlet hole.

(a) Since the depth L of the gas outlet hole H becomes shallower due to the inclusion of the residual pressure valve R, the screw fitting dimension of equipment such as a pressure reducer connected to the gas outlet hole H becomes shorter. If the connection strength is insufficient, existing equipment cannot be used.

In order to solve this problem, if the protrusion amount K of the gas outlet hole H is increased and the depth L of the gas outlet hole H is lengthened, the safety cap that is screwed onto the neck of the cylinder body and covers the cylinder valve will protrude too much. The gas outlet tube GKa fitting case cannot be screwed onto the cylinder body.

←) The residual pressure valve is a gas outlet hole H that is restricted by connected equipment, etc.
Since it is installed inside the gas outlet hole H, its outer diameter must be set to be equal to or less than the inner diameter d of the gas outlet hole H, and a sufficient cross-sectional area of the flow path within the gas outlet hole H must be ensured.

This may result in unreasonable design of the residual pressure valve or inability to obtain a sufficient gas flow rate.

(c) Since the peripheral wall portion of the gas outlet hole H constitutes the valve box of the residual pressure valve, the residual pressure valve body must be assembled within the narrow gas outlet hole H, making the assembly work cumbersome.

Then, we proposed a system in which a residual pressure valve was installed in the main valve chamber of the pulp cylinder body in combination with the main valve (Japanese Patent Laid-Open No. 49-911851).

(See FIG. 4B) However, in this case, since the residual pressure valve is installed in the main valve chamber in combination with the main valve, there are the following drawbacks.

B) Since the main valve V and the residual pressure valve R are organically combined within the narrow main valve chamber, the structures of both valves become complicated, making assembly difficult and increasing manufacturing costs.

(e) When a valve malfunctions, it may become unclear which of the main valve V or the residual pressure valve R has failed, making it difficult to accurately locate the malfunctioning location, and the main valve V or residual pressure valve R
Since they cannot be separated and both must be disassembled and reassembled at the same time, repair becomes difficult.

When repairing a malfunctioning residual pressure valve, the gas in the cylinder must be completely discharged, so there is a loss due to gas release, or it takes a lot of effort to replace the gas, and when one valve is disassembled. In addition, since outside air flows into the cylinder as impure gas, operations such as evacuation and gas replacement are required when refilling.

The present invention was proposed in view of these points, and takes advantage of the respective advantages of the above two conventional examples, and
In order to solve this problem, as a means to achieve this purpose, a residual pressure valve chamber is formed in the middle of the gas passage connecting the main valve chamber and the gas outlet hole in the valve box. The box is opened on a side different from the side where the gas outlet hole is formed, and a cassette type automatic residual pressure valve is removably inserted and fixed in the residual pressure valve chamber.
This cassette type automatic residual pressure valve automatically closes with a valve closing spring when the internal pressure of the cylinder falls below the residual pressure set value. The valve is characterized in that when a backflow occurs, the valve is automatically closed using the backflow gas pressure and a valve closing spring.

Embodiments of the present invention will be described below with reference to the drawings.

Figure 1 is a longitudinal sectional front view of the cylinder valve, Figure 2 is Figure 1A
-A sectional view.

In the figure, reference numeral 1 denotes a valve box, and a male screw 3 fixed to the cylinder 2 is formed at the lower part of the circumferential surface, a gas inlet hole 4 is opened at the lower end surface, and a main valve chamber 5 is formed in the upper half of the box. A residual pressure valve chamber 6 is formed with an opening facing upward, and a residual pressure valve chamber 6 is formed with a rightward opening on the right side of the intermediate height, and a gas outlet hole 7 is formed with a leftward opening on the left side of the intermediate height. A female thread 8 for fixing a pressure reducing valve or the like is formed on the inner peripheral surface of the hole 7, and a safety valve chamber 9 is formed at the rear side of the intermediate height in a backward opening shape, and this safety valve chamber 9 is screwed into this from behind. The safety valve 10 is closed.

A main valve chamber 5 is connected to the gas inlet 4 through an inlet hole 11, a residual pressure valve chamber 6 is connected to the main valve chamber 5 through an intermediate hole 1'2, and a gas outlet hole 7 is connected to the residual pressure valve chamber 6 through an outlet hole 13. Connected, cylinder 2
The gas inside passes through the gas port 4, the main valve chamber 5, the residual pressure valve chamber 6, and the gas outlet hole 7 in order to flow out to the outside.

The safety valve chamber 9 is connected to the inlet hole 11 through an outlet hole 14.

A main valve 15 is installed inside the main valve chamber 5;
A valve stem 17 is pivotally supported by a retaining nut 16 screwed to close the upper part of the main valve 15, and when the handle 18 is rotated to the left or right, the main valve 15 is rotated in the same direction via the valve stem 17. This main valve 15 is guided by a screw fitting part 19 and moves up and down to open and close a valve seat 20 at the entrance of the main valve chamber 5.

A cassette type automatic residual pressure valve 21 is removably inserted and fixed into the residual pressure valve chamber 6 by screw fitting 22 .

This cassette type automatic residual pressure valve 21 is constructed as shown in FIG.

That is, the reference numeral 23 is a cassette in the form of a horizontally placed cylinder with a bottom, into which a valve body 24 is inserted with an O-ring 25 so as to be slidable from side to side like a honeycomb.

This valve body 24 is pushed toward the open end side of the cassette 23 by a valve closing spring 26, and a valve face 27 made of an O-ring that is fitted and fixed in the middle part of the left end face of the valve body is pressed against the left end face of the residual pressure valve chamber 6. Exit hole 1
It is in closing contact with a taper valve seat 28 formed on the peripheral wall of the outlet opening of No. 3.

Reference numeral 29 is a valve opening pressure receiving surface, which opens the valve body 24 against the valve closing spring 26 by the gas pressure in the residual pressure valve chamber 6. It is shaped like an annular end face located in a step-like manner on the right side, and faces the residual pressure valve chamber 6.

A stopper pin 33 fixedly protruding from the open end side portion of the cassette 23 projects into a recessed portion 35 which is cut into the right side from a part of the valve opening pressure receiving surface 29.

Reference numeral 30 denotes a communication hole, which introduces the gas flowing back from the gas outlet hole 13 into the valve-closing back pressure chamber 31 formed on the back surface of the valve body 24 in the cassette 23. It is provided transparently on the inner side of the surface 2T.

The inner half 34 of the communication hole 30 is formed as a rotation operation hole with a square cross section, and the gas outlet hole 7 and the gas outlet hole 13 are connected to each other from the outside.
When the valve body 24 is pushed half a turn to the right from the closed state shown in FIG. is received by the stopper pin 33, the valve body 24 is kept in the open state, and gas can be filled into the cylinder 2. The valve body 24 is further rotated by half a turn to close it as shown in FIG. When placed in the valve state, the valve body 24 is configured to return to its original operating state.

Next, its effect will be explained.

When the main valve 15 is opened by operating the handle 18 from a state where the cylinder 2 is filled with gas, the gas in the cylinder 2 flows into the residual pressure valve chamber 6 via the main valve chamber 5, and the gas is applied to the valve opening pressure receiving surface 29. The valve body 24 is opened against the valve closing spring 26 by the valve opening force caused by the pressure, and the gas flows out through the gas outlet hole 13 and the gas outlet hole 7.

When the internal pressure of cylinder 2 drops to the set residual pressure that is close to empty,
The valve opening force due to the gas pressure applied to the valve opening pressure receiving surface 29 in the residual pressure valve chamber 6 is overcome by the valve closing spring 26, and the valve body 2475 closes with the set residual pressure remaining in the cylinder 2.

In addition, when two or more types of gas taken out from two or more cylinders 2 are mixed and taken out in the gas outlet path before the residual pressure drops to the set residual pressure, the difference in residual pressure between the cylinders 2 causes the difference between the cylinders on the low pressure side. When the mixed gas starts to flow back, the backflow gas is forced into the valve-closing back pressure chamber 31 from the outlet hole 13 through the communication hole 30, acts as a valve-closing force, and works together with the valve-closing spring 26. The valve body 24 is automatically closed.

In this case, as the backflow gas pressure is high and the backflow is likely to occur at a high speed, the valve closing force in the valve-closing back pressure chamber 31 due to the backflow gas pressure increases, so that the valve body 24 rapidly becomes stronger. Since it is closed, the backflow is reliably prevented.

When collecting the empty cylinder 2 and refilling it with gas, turn the valve body 24 half a turn using the valve opening tool 32 to open the valve, and then connect the gas filling port of the gas filling device to the gas outlet. hole 7
, the main valve 15 is opened, and the filling gas is pumped toward the cylinder 2.

Then, the filling gas passes through the outlet hole 7, the outlet hole 13, the residual pressure valve chamber 6, and the main valve chamber 5, flows into the cylinder 2, and is filled.

After this gas filling is completed, close the main valve 15, remove the gas filling port from the gas outlet hole 7, and use the valve opening tool 32 to open the valve body 2.
4 by half a turn to return to the valve closed state, that is, the valve operating state.

As explained above in the embodiments, the present invention forms the residual pressure valve chamber in the valve box separately from the outlet hole and the main valve chamber, and connects the gas inlet opening at the bottom of the valve box and the lower part of the main valve chamber to the inlet. The main valve chamber and the residual pressure valve chamber are connected through a hole, the main valve chamber and the residual pressure valve chamber are connected through an intermediate hole, the residual pressure valve chamber and a gas outlet hole opened on the circumferential surface of the valve box are connected through an outlet hole, and the main valve is connected to the main valve chamber. A valve seat is formed at the end of the main valve chamber on the gas inlet hole side, and the residual pressure valve chamber is opened on a side different from the side where the gas outlet hole is formed in the valve box. The automatic residual pressure valve is removably inserted and fixed, and the cassette type automatic residual pressure valve consists of a bottomed cylindrical cassette, a valve body slidably inserted into the cassette, and a valve closing spring, and the valve body closes. The valve spring pushes the cassette toward the opening end, and the valve surface is brought into closing contact with the valve seat formed at the outlet opening of the outlet hole of the residual pressure valve chamber, and the valve element is opened against the closing spring. A valve opening pressure receiving surface 9 is placed in the residual pressure valve chamber on the outer periphery of the valve body from the valve seat, and a closing valve formed on the back surface of the valve body is formed in the cassette to prevent gas flowing backward through the gas outlet hole. A communication hole leading to the back pressure chamber is provided inside the valve surface of the valve body, and the pressure receiving surface in the closed back pressure chamber is determined from the area inside the valve surface of the valve body exposed to the gas outlet hole. Since the valve body is formed wide and the valve body can be operated to the open state by a valve opening operating tool inserted from the outside through the outlet hole, the following effects are achieved.

B. Due to the presence of the residual pressure valve, when the internal pressure of the cylinder drops below the set residual pressure, the residual pressure valve will close and the main valve will open. It is possible to reliably prevent impurities from entering the cylinder, and it is possible to prevent a decrease in gas purity and contamination within the cylinder.

Since the residual pressure valve is installed in a residual pressure valve chamber formed in a different location from the gas outlet hole of the valve box, unlike conventional valves installed inside the gas outlet hole, the depth dimension of the gas outlet hole cannot be adjusted. It can be taken deep enough.

As a result, the screw fitting dimension of the pressure reducing valve connected to the gas outlet hole can be sufficiently increased, and the connection can be made firmly.

The amount of protrusion of the gas outlet hole forming portion can be reduced, and the cylinder valve can be protected with a conventionally used cylinder pulp cover.

Therefore, it can be easily applied to a cylinder body that is not equipped with a cylinder valve equipped with a residual pressure valve.

C.Also, since the residual pressure valve chamber is formed between the main valve chamber and the gas outlet hole in the valve box, its size can be freely formed, and the residual pressure valve is located between the main valve chamber and the gas outlet hole. The size can be freely formed without being restricted by the size or the size of the gas outlet hole.

As a result, the design of the residual pressure valve is not unreasonable and its operating accuracy can be maintained at a high level, and the cross-sectional area of the gas flow path can also be formed sufficiently large to reduce the gas flow resistance. .

2.Repairs of the residual pressure valve can be carried out with the main valve closed and gas outflow from the cylinder stopped, which eliminates the loss caused by gas discharge inside the cylinder and the large amount of effort required to replace the gas. Moreover, it also prevents outside air from entering the cylinder.

E. A cylinder valve with a malfunctioning residual pressure valve can be easily and quickly repaired by anyone, anytime, anywhere by simply replacing the malfunctioning residual pressure valve with a new residual pressure valve.

When two or more types of gas taken out from two or more cylinders are mixed in the gas outlet path and increased to the outside, the mixed gas may leak into the low-pressure cylinder due to residual pressure difference between the cylinders or backfire. When the gas is about to start flowing back, the backflow gas is forced into the valve-closing back pressure chamber from the outlet hole through the communication hole, acts as a valve-closing force, and works with the valve-closing spring to close the valve body. Since the cylinder is automatically closed, it is possible to reliably prevent the mixed gas and flashback from flowing back into the cylinder.

This makes it possible to prevent the purity of the gas in the cylinder from decreasing or from fire entering the cylinder and causing an explosion.

! ,When this backflow occurs, the backflow gas pressure is high,
As the backflow occurs at high speed, the valve closing force in the valve-closing back pressure chamber due to the backflow gas pressure becomes stronger, and the valve body is rapidly and strongly closed, so no high-pressure backflow occurs. It is also possible to reliably block the backflow.

[Brief explanation of drawings]

1 to 3 show an embodiment of the present invention, FIG. 1 is a vertical front view, FIG. 2 is a sectional view taken along the line A-A in FIG. 1, and FIG. 3 is an enlarged view of part B in FIG. 1. FIGS. 4A and 4B are longitudinal cross-sectional views of the main parts of the previously proposed device, respectively. 1...Valve box, 2...Cylinder, 4...
...Gas inlet, 5...Main valve chamber, 6...
・Residual pressure valve chamber, 7...Gas outlet hole, 11...
...Inlet hole, 12... Meson L 13...
...Outlet hole, 15...Main valve, 20...
Valve seat, 21... Automatic residual pressure valve, 23...
Cassette, 24... Valve body, 26... Valve closing spring, 27... Valve surface, 28... Valve seat, 29... Valve opening pressure receiving surface, 30...Communication hole, 32...Valve opening operating tool.

Claims (1)

[Scope of utility model registration request] A gas valve 4, a main valve chamber 5, a residual pressure valve chamber 6, and a gas outlet hole 7 are formed in a valve box 1 screwed onto the neck of a cylinder 2, respectively,
The gas port 4 opened at the bottom of the valve box 1 and the lower part of the main valve chamber 5 are connected by an inlet hole 11, the main valve chamber 5 and the residual pressure valve chamber 6 are connected by an intermediate hole 12, and the residual pressure valve chamber 6 and The main valve 1 is connected to the gas outlet hole 7 opened on the circumferential surface of the valve box through an outlet hole 13, and the main valve 1 is connected to the main valve chamber 5.
5 is internally operated so that it can be manually operated, and the gas inlet hole 11 of the main valve chamber 5
A valve seat 20 is formed at the side end, and the residual pressure valve chamber 6 is opened on a side of the valve box 1 that is different from the side where the gas outlet hole 7 is formed, and a cassette type automatic residual pressure valve 21 is removably inserted into this opening. The cassette-type automatic residual pressure valve 21 is fixed and has a bottomed cylindrical cassette 23 and a valve body 2 inserted into the cassette 23 in a sealed and slidable manner.
4 and a valve-closing spring 26, the valve body 24 is brought to the open end side of the cassette 23 by the valve-closing spring 26, and the valve surface 2
7 is brought into closing contact with the valve seat 28 formed at the outlet opening of the outlet hole 13 of the residual pressure valve chamber 6, and the valve opening pressure receiving surface 29 which opens the valve body 24 against the valve closing spring 26 is brought into contact with the valve body 24. The residual pressure valve chamber 6 is formed on the outer periphery of the valve seat 27 of the gas outlet hole 13.
A communication hole 30 is connected to the valve body 2 through a communication hole 30 for introducing the gas flowing backward into the valve-closing back pressure chamber 31 formed on the back surface of the valve body 24 within the cassette 23.
4, and the pressure-receiving area in the valve-closing back pressure chamber 31 is made larger than the area inside the valve surface of the valve body 24 exposed to the gas outlet hole 13; This is a cylinder valve with a cassette type automatic residual pressure valve, in which a valve body 24 can be operated to an open state with a valve opening operating tool 32 inserted from the outside through an outlet hole 7 and an outlet hole 13.