JPS62118587A - Replacing method for sealed gas in container - Google Patents

Abstract

PURPOSE:To obtain a simple gas replacing method, which ensures the accuracy of a mixing ratio in repeating control and can change the mixing ratio freely and accurately, by providing a gas system along a path from a container to a differential pressure gage, a minitank, a valve and again to the container, and supplying the new gases based on the indication of the differential pressure gage. CONSTITUTION:The pressure of mixed gases 2, which are sealed in a container 1 is measured by a pressure gage 3. A pipe, which is directly communicated to the container 1, is connected to one side of a differential pressure gage 12. From a pipe, which is communicated to the other side of the differential pressure gage 12, a gas system is provided along a path covering a minitank 13, a valve 14 and the container 1. When the gages are replaced, the new gases are supplied based on the indication of the differential pressure gage 12. For example, when the sealed gases are partially replaced, at first, the valve 14 is closed, then a discharge valve 4 is released, a required amount of the sealed gases 2 are discharged and the discharge valve 4 is closed. Then, the differential pressure gage 12 indicates the value corresponding to the pressure difference. Then, a feeding valve 5 is opened. Thereafter, opening and closing of valves 9-11 are controlled, and various gases are supplied from cylinders A, B and C at a required mixing ratio until the indication of the differential pressure gage 12 becomes zero.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for exchanging a mixed gas sealed in a container in, for example, an excimer laser device.

[Conventional technology]

FIG. 2 is a schematic diagram illustrating a method of exchanging gas within a container in a conventional FT. In the figure, (1) is a container, (2) is a gas sealed in the container (1), (3) is a pressure gauge that measures the pressure of the sealed gas (2), (
4) is the gas (2) release valve, (5) is the gas (2)
supply valves (6) to (8) supply gas A to the container (1).
, B, and C, and opening/closing valves (6) to (8) to the cylinders for bagasse A, B, and C (9) to α1).

Next, a gas exchange method in the above conventional configuration will be explained. First, fully open the discharge valve (4) and open the container (1).
) After releasing the necessary amount of gas (2) sealed in the gas tank (2) with the pressure gauge (3), the release valve (4) is completely closed. Next, open the supply valve (5), open and close the valve (9) to α℃ for a total of 11 times, and check the pressure gauge (
Since the measurement in step 3), all gases are co-supplied to the container (1) at a predetermined mixing ratio up to the original pressure.

[Problem that the invention seeks to solve]

Since the conventional gas exchange method is configured as described above, the accuracy of the mixture ratio is determined by the pressure accuracy of 6f when partially exchanging the mixed gas sealed in the container. Therefore, in the case of gases with a small mixing ratio, repeatability cannot be guaranteed.

In addition, in order to ensure the precision of the mixing ratio, if a mixed gas cylinder made in advance with a predetermined mixing ratio is used, the repeatability is guaranteed, but there is a problem that the mixing ratio cannot be changed. there were.

This invention was made to solve the above-mentioned problems, and it not only guarantees the accuracy of the mixing ratio in repeated control in partial gas exchange of the mixed gas sealed in a container, but also allows the mixing ratio to be changed freely. can be changed with high precision to
``The purpose is to obtain a gas exchange method that can be delivered easily.

[Means for solving problems]

In the gas exchange method according to the present invention, in addition to a pressure gauge that measures the total pressure of a mixed gas sealed in a container, the pressure gauge is connected to one side of a piping #'fr differential pressure gauge that directly communicates with the container; The pipe R that communicates with the opposite side of the pressure gauge is a new gas system that connects to the container via a mini-tank and a valve.

[Effect]

The partial gas exchange method according to the present invention is such that in a carefully installed gas system, the valves in the system are always kept open so that the pressure on both sides of the differential pressure gauge is fully balanced, and during gas exchange, the pressure on both sides of the differential pressure gauge is balanced. The valve is fully closed and the gas sealed in the container is released by the replacement amount. As a result, a pressure difference occurs on both sides of the differential pressure gauge. Therefore, place both the differential pressure gauges in a new gas container so that the pressure difference on both sides disappears.

[Embodiments of the invention]

Hereinafter, the schematic configuration diagram of one embodiment of the present invention shown in FIG. 1 will be explained. In the figure, one end (E) is at a2.
11 is a differential pressure gauge connected to the piping that communicates with the contact vessel (1), (1 and 9 are distributed to one side (F) of the differential pressure gauge (2) and connected to the reta mini tank, α4 is this mini tank αJ and the container ( 1
) is the valve installed at rC between In addition, code (1) ~
The portion reduced at α℃ is the same as that of the conventional configuration shown in Fig. 2, so the explanation will be omitted.Now, by keeping the valve α4) fully open at all times,
There is no pressure difference on both sides of the differential pressure gauge (6) because it is that of the gas (2) sealed in the container (1), which is a so-called zero indication. Next, when performing partial gas exchange of the sealed gas (2) in the container (1), first close the valve α4, then fully open the outflow valve (4), and fill the container (1) with the gas. Gas (2) is released in the required exchange amount. Then the release valve (4)
By fully closing, the mini tank side (F
) is maintained at the pressure before gas release, while the other (g) is the pressure of the sealed gas (2) in container (1) after release of σ gas, so the differential pressure gauge (a) is Instruct the debt corresponding to that pressure difference. Next, the supply valve (5
) After fully releasing the pressure, control the opening and closing of valves (9) to αη while monitoring the indication from the differential pressure gauge (2).
Each gas is supplied from gas cylinders A, B, and C at the required mixing ratio until the pressure in the so-called container (1) becomes zero, which is the original pressure.

Here, the limit of the pressure gauge (3) and the differential pressure gauge (6) at 8 degrees is 061% of the full scale value, and the range is about 1/10 of the pressure gauge (3). By using the differential pressure gauge α2, the precision of the gas exchange method using the conventional structure is more than 10 times higher, and the partial gas exchange control function described above becomes possible. In addition, all the sealed gas (
2) When replacing the entire valve α4 until the release is -1,
By controlling using only the pressure gauge (3) without using the entire indication of the differential pressure gauge (c), the same accuracy as the conventional device can be obtained.

[Effects of the Invention] As described above, according to the present invention, the full scale value of the pressure gauge is 115 to . ．． By using a differential pressure gauge with a full range of 1/1[], it is possible to easily and accurately partially replace the sealed gas in the container.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing the entire gas exchange system according to an embodiment of the present invention, and FIG. 2 is a schematic diagram showing the conventional gas exchange system. In the figure, (1) is a container, (2) is a gas, (3) is a pressure gauge,
(4) is a discharge valve, (5) is a UTtC supply valve, (
6)~(8) Bagasse cylinder, (9)~α]) valve,
(2) is a differential pressure gauge, a CI3 hamini tank, and a valve at α4. Note that the same or corresponding parts are indicated by the same reference numerals in the valley diagram.

Claims (1)

[Claims] In addition to the pressure gauge that measures the pressure of the mixed gas sealed in the container, a pipe that directly communicates with the container is connected to one side of the differential pressure gauge, and a mini tank and valve are connected from the pipe that communicates to the other side of the differential pressure gauge. A method for exchanging gas sealed in a container, characterized in that a gas system is installed to return the gas to the container via the container, and at the time of gas exchange, new gas is supplied according to instructions from the differential pressure gauge.