JPS616472A - Leak apparatus - Google Patents

Abstract

PURPOSE:To prevent the dust frmation in a vacuum container by introducing leaked gas little by little into the vacuum container at the initial stage of leak of the vacuum container. CONSTITUTION:When a valve 28 is opened, the leaked gas branched from a leaked-gas introducing line 26 into a branched line 27 is introduced into a space B. The leaked gas is introduced little by little into a vacuum container 10 from the space B through a gas introducing slit 31. When the force due to the pressure difference between the spaces A and B reduces than the force of a coil spring 30, an orifice 23 is opened gradually. The amount of the leaked gas introduced into the vacuum container 10 from the space B increases because of the increase of the area of the opening.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a leak device, and particularly to a leak device suitable for leaking a vacuum container.

[Background of the invention]

As a technique for leaking gas by introducing it into a vacuum container, for example, as shown in Japanese Utility Model Application Publication No. 58-150836, there is a technique for leaking by introducing a leak gas into a vacuum container, as shown in FIG. A technique is known in which leak gas is introduced into a vacuum container by adjusting the pressure within the container.

With this technique, a large amount of leak gas is rapidly introduced into the vacuum container at the initial stage of leakage of the vacuum container, so there is a problem in that dust is generated within the vacuum container.

[Purpose of the invention]

The purpose of the present invention is to introduce leak gas into the vacuum container little by little at the initial stage of leakage in the vacuum container, so that -'
It is an object of the present invention to provide a leak device capable of preventing dust generation within a vacuum container.

[Summary of the invention]

The present invention provides a leak device including a valve body having a valve hole communicating with a leak hole of a vacuum container, a valve box airtightly provided in the valve body, and an orifice inserted into the valve hole with a variable opening area. An orifice installed inside the valve box via the support and the bellows flange, a leak gas introduction line that communicates with the inside of the bellows flange and is connected to the valve box, and a leak gas introduction line that branches from the line and connects to the inside of the valve box outside the bellows flange. an elastic member provided between the valve body and the orifice support so as to be able to expand the opening area;
It is characterized by a gas introduction slit or a gas introduction hole that introduces leak gas introduced into the valve box outside the bellows flange from the leak gas introduction branch line into the vacuum vessel from inside the valve box little by little. The leak gas is introduced little by little at the beginning of leakage from the container.

[Embodiments of the invention]

An embodiment of the present invention will be described with reference to the drawings.

In the drawing, a funnel-shaped hole is bored in the side wall of the vacuum vessel 10, which in this case is a leak hole and also a valve hole. Therefore, in this case, the vacuum container 10
The side wall of the valve body 21 serves as a valve body 21, and a valve box n is airtightly provided on the valve body 21. An orifice n having a shape corresponding to that of the hole, that is, a truncated cone, is inserted into the hole so that its opening area can be changed, and is installed in the valve body ρ via the orifice support U and the bellows flange b. The valve box η is connected to the leak gas introduction line in communication with the inside of the bellows flange δ, that is, the space A formed by the side wall of the valve case n, the orifice support row, and the bellows flange δ. The more branched leak gas introduction branch line n is
It is connected to the inside of the valve box n outside the bellows flange δ, that is, to the space B that is blocked off from the space A so as to be able to communicate with it. in this case,
The leak gas introduction branch line n is provided with a valve, and a filter 4 is provided on the downstream side of the valve. An elastic body, such as a coil spring (9), is provided between the valve body 21 and the orifice support row so as to be able to expand the opening area. The leak gas introduced into the space B from the leak gas introduction branch line n is introduced little by little into the vacuum container 10 from the space B. In this case, the gas introduction slit 31
is formed on the surface of the orifice that contacts the hole.

The drawing shows a state in which the orifice Z is closed and the inside of the vacuum vessel IO is at a predetermined vacuum pressure, and the vacuum vessel IO is leaked from this state as follows.

In the drawing, when the valve Z is opened, the leak gas that is diverted from the leak gas introduction line to the leak gas introduction branch line is introduced into the space B after being purified by the filter 4. The leak gas introduced into the space B is introduced little by little into the vacuum container 10 from the space B via the gas introduction slit 31.

As a result, the pressure inside the vacuum container 10 gradually increases. After that, when the force that presses the orifice n against the hole hole due to the pressure difference between space A and space B becomes smaller than the spring force of the coil spring, this pressing is done due to the difference between the force and the spring force. The orifice n is gradually opened and the opening area is expanded. Due to this enlargement of the opening area, the amount of leak gas introduced into the vacuum container 10 from the space B increases, so that the inside of the vacuum container 10 is quickly leaked.

A leak device like this embodiment provides the following effects.

(1) At the initial stage of leakage in the vacuum container, leak gas is introduced into the vacuum container little by little through the gas introduction slit.
Dust generation inside the vacuum container can be prevented.

(2) Since the amount of leak gas introduced into the vacuum container increases after the initial stage of leakage, the time required for leakage of the vacuum container can be shortened.

In this embodiment, the gas introduction slit is formed in the orifice, but the gas introduction slit may be formed in the hole. Further, the gas introduction hole may be formed in another member to communicate the inside of the vacuum container and the space B.

〔Effect of the invention〕

As explained above, the present invention provides a leak device including a valve body having a valve hole communicating with a leak hole of a vacuum container, a valve box airtightly provided in the valve body, and an opening in the valve hole. An orifice inserted in a variable area and installed inside the valve box via an orifice support and a bellows flange, a gas introduction line that communicates with the inside of the bellows flange and is connected to the valve box, and from the line, a leak gas introduction branch line that is branched and connected to the valve box so that it can communicate with the inside of the valve box outside the bellows flange; an elastic body that is provided between the valve body and the orifice support so that the opening area can be expanded; By constructing a gas introduction slit or gas introduction hole that introduces leak gas introduced into the valve box outside the bellows flange from the leak gas introduction branch line into the vacuum container from inside the valve box little by little, it is possible to prevent the initial leakage of the vacuum container. Since the leak gas can be introduced into the vacuum container little by little, dust generation within the vacuum container can be prevented.

[Brief explanation of the drawing]

The drawing is a sectional view showing an embodiment of a leak device according to the present invention.

Claims (1)

[Claims] 1. A valve body having a valve hole communicating with the leak hole of the vacuum container, a valve box airtightly provided to the valve body, an orifice support body and a bellows flange inserted into the valve hole so as to have a variable opening area. an orifice installed in the valve box via a leak gas introduction line that communicates with the inside of the bellows flange and is connected to the valve box, and a leak gas introduction line that branches from the line and connects to the inside of the valve box outside the bellows flange. a leak gas introduction branch line connected to the valve box in a communicable manner; an elastic body provided between the valve body and the orifice support so that the opening area can be expanded; and a leak gas introduction branch line connected to the valve box; A leak device comprising a gas introduction slit or a gas introduction hole for introducing lease gas introduced into the valve box outside the flange into the vacuum container from inside the valve box little by little.