JPS63266274A - Main valve for gas container - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a main valve for a gas container that is used by being attached to a gas container filled with liquefied gas, high pressure gas, or the like.

In recent years, ultrapure gases have been used in various industrial fields. For example, there are gases used in semiconductor manufacturing processes, and the purity of these so-called process gases has a significant impact on the quality of the manufactured products. Therefore, great care must be taken to maintain high purity of the gas. Furthermore, some of these process gases are highly toxic or have a high risk of explosion, so safety is required when handling them.

Incidentally, these process gases are normally filled into gas containers at a factory and supplied to users in that state.

At this time, both when filling the gas 2 and when the user uses the gas in the container, this is done through the main valve attached to the container.

(Prior Art) An example of a main valve conventionally used in such a gas container is shown in FIG.

In the figure, 51 is a main body between the main valves for the gas container. Inside the main body 51, a valve chamber 53 whose upper part is closed with a diaphragm 52 is formed, and between the valve bodies urged upward by a compression spring. It is stored. When the valve body 55 is pushed down by the spindle 56, it closes the upstream gas passage 57 and cuts off communication with the downstream gas passage 58. The main valve is attached to a gas container (not shown) with screws 59.

When filling with gas, the valve is in the open state shown in FIG. 3, and gas flows from the gas tank (not shown) from the downstream flow path to the container through the upstream channel 57. When filling is completed, the valve is closed. and disconnected from the gas tank.

When using gas, the downstream passage 58 between the valves is connected to various devices and then the valves are opened. The gas is released from the container through the upstream channel 57 and the downstream channel in a direction opposite to that during filling.

(Problems to be Solved by the Invention) In the gas container main valve configured as described above, when the outer end 58a between the downstream gas passages is open,
In other words, the inside of the valve chamber 53 is When exposed to the atmosphere, it becomes ＼. That is, as is clear from FIG. 2, air can enter the valve chamber 53 from the downstream gas passage 58 regardless of whether or not the valve body 55 closes the upstream gas passage 57.

If atmospheric components remain in the valve chamber 55 and gas is filled or used by connecting the downstream gas passage to a gas tank or various devices, the purity of the gas will naturally decrease.
Furthermore, when the gas is a natural gas, oxides are formed and a large amount of particles are generated.

If such a gas containing impurities is used, the quality of the product or yield will be reduced, and in some cases, the equipment may be damaged. Therefore, when attaching the main valve to the gas container, filling it with gas, or connecting various devices to use the gas, cleaning operations such as evacuation with a vacuum pump or purging with inert gas replacement are required. is repeated. However, since the valve body 55, spring 54, etc. are present in the valve chamber 53, cleaning the inside of the valve chamber by the above-mentioned operations, especially gas filling and inert gas replacement operations performed at the time of use, takes a long time. Replacement reliability is also low.

Furthermore, in the conventional main valve described above, the valve body 55 closes only the upstream passage 57, so if the diaphragm 52 is damaged during gas use, it is not possible to prevent gas from flowing out from the downstream side even if the valve is closed.

Further, when filling with gas, the inside of the container is made vacuum, and the gas flowing from the downstream side acts to press the valve body & into contact with the bottom wall surface 61 of the valve chamber 53. Therefore, in order to fill with gas, a strong spring is used to separate the valve body 55 from the bottom wall surface 61. This strong 7e force constantly applies a large compressive force to the diaphragm, which poses a risk of reducing the durability of the diaphragm.

(Means for Solving the Problems) The present invention has been made to solve the above-mentioned problems of the conventional main valve for gas containers.According to the present invention,
It is used by being attached to a gas container, and has an upstream gas flow path connected to the gas container at one end, a downstream gas path connected to an external device at one end, a valve chamber, and is movable up and down to the valve chamber. A main valve for a gas container, comprising: a valve body disposed in the upstream side and the downstream side gas flow path; A main valve for a gas container is provided, in which the other ends of the gas passages are opened at the bottom wall surface of the valve chamber, and the two other ends are opened and closed simultaneously by the valve body.

(Example) Hereinafter, the present invention will be explained in detail based on the drawings.

In FIG. 1, 1 is a main valve for a gas container according to the first embodiment of the present invention, 2 is a main body, and 3 is a screw threaded into an upper end opening 5 of a hole 4 formed in the upper half of the main body 2. This is the bonnet that is attached to the vehicle.

The lower end 3a of the bonnet 3 cooperates with a shoulder 4a provided in the hole 4 to clamp the outer peripheral edge 6a of the diaphragm 6. A lower portion of the hole 4 partitioned off by the diaphragm 6 forms a valve chamber 7 .

A valve body 8 is housed in the valve chamber 7 so as to be movable up and down.
It is urged upward by a compression spring 12 disposed between a flange 9 provided at the upper end of the valve body 8 and a bottom wall surface 11 of the valve chamber 7 .

A spindle 13 is screwed into the bonnet 3 so as to be movable up and down, and a plate 14 buried in the lower end of the spindle 13 is connected to a diaphragm 6.
It is in contact with the outer surface of the Rotation of the handle 15 lowers the spindle 13, thereby moving the valve body 8 downwardly through the diaphragm 6 from the position shown in FIG. When the handle 15 is rotated in the opposite direction, the valve body 8 is moved downward by the spring 12 and returns to the state shown in FIG.

A circular valve seat 16 is formed approximately in the center of the bottom wall surface 11 of the valve chamber 7 and is raised one step higher than the bottom wall surface 11.

A tapered screw is carved into the outer circumference of the container attachment part 17 formed in the lower part of the main body 2 so that it can be attached to a gas container (not shown). A side gas passage 18 is formed to penetrate vertically, and its upper end 18a opens into the valve chamber 7 at approximately the center of the valve seat 16. The upstream gas flow path 18 serves as a gas flow path that communicates the valve chamber 7 with the inside of the gas container. Further, a downstream gas flow path 19 is formed to extend laterally inside a piping attachment portion 21 provided at approximately the center in the height direction of the main body 2, and one end thereof 1
9a is an annular opening surrounding the upper end 18a of the upstream gas passage 18 and opens into the valve chamber at the valve seat 16, and the other end 19b opens at the outer end of the piping attachment part 21. The downstream gas flow path 19 serves as a gas flow path that communicates the valve chamber 7 with a gas tank or various devices.

Figure 1 shows the open state of valve 1.
5 is rotated to move the valve body 8 downward, and when the sheet lateral movement ρ embedded in the lower end of the valve body 8 is pressed against the valve seat 16,
Due to the lateral movement n of the seat, both the upper end 18a of the upstream gas flow path and one end 19a of the downstream gas flow path, which are open to the valve chamber 7, are closed.

Note that a side flow path n is provided in the middle of the upstream gas flow path 18,
A safety plug is installed in the opening. U is a packing, 5 is a safety plate, and A is a fusible alloy.

Note that in this embodiment, the end of the downstream gas flow path that opens into the valve chamber is formed into an annular shape so as to surround the end of the upstream gas flow path, but it is not necessarily shaped like this. This is not necessary, and can be done by configuring both ends to be opened and closed simultaneously by the valve body.

(Effects of the Invention) According to the present invention, as described above, one end of each of the upstream gas flow path and the downstream gas flow path of the main valve for gas appliances is opened to the valve chamber, and the gas flow path is disposed within the valve chamber. The valve body is configured to open and close not only the upstream end but also the downstream end at the same time, so once the valve is closed, even if the other end of the downstream gas flow path is open, it will not work as usual. Unlike the main valve, the inside of the valve chamber is not exposed to the atmosphere. Therefore, it is possible to prevent the conventional problem of stagnation of air in the valve chamber or the generation of oxides due to natural gas and atmospheric components, and it is possible to maintain the gas at a high purity.

Further, only the downstream flow path is exposed to the atmosphere, and the inside of the flow path has a simple shape and there are no obstacles like the inside of the valve chamber. Therefore, vacuuming, inert gas ξ
Cleaning work such as - can be easily carried out, and the working time required can be significantly shortened.

According to the main valve for a gas container according to the present invention, not only the upstream side but also the downstream gas flow path can be closed by closing the valve, so if the diaphragm breaks during gas use, etc. It is also possible to prevent gas from flowing out from the downstream gas flow path, which could not be prevented with conventional main valves. This is especially important if the gas being used is toxic.

Further, in the valve according to the present invention, when filling with gas, gas is ejected from the downstream gas flow path into the valve chamber in a direction that pushes the valve body upward. Therefore, it is no longer necessary to use an extremely strong spring to bias the valve body upward as in the past; a weak spring is sufficient. This reduces the compressive force acting on the diaphragm between the valve body and the plate, ensuring the durability of the diaphragm and improving safety.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a gas container main valve according to an embodiment of the present invention, and FIG. 2 is a sectional view of a conventional main valve. 1... Main valve for gas container 2... Main body 3... Bonnet 6... Diaphragm 8... Valve body 18... Upstream gas flow path 19... Downstream gas flow path

Claims (1)

[Claims] An upstream gas passage that is attached to a gas container and has one end connected to the inside of the gas container, a downstream gas passage that has one end connected to an external device, a valve chamber, and a valve chamber that is vertically movable within the valve chamber. In the gas container main valve, the gas container main valve is provided with a valve body that communicates with and shuts off the other ends of the upstream and downstream gas passages by the valve body. A gas container main valve characterized in that both of its other ends are opened at the bottom wall surface of the valve chamber, and the two other ends are opened and closed simultaneously by the valve body.