JPH02298677A - Relief valve exhausting structure of cryo-pump - 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] This invention relates to a relief valve exhaust structure for a cryopump.

[Prior Art] FIG. 2 is a longitudinal sectional side view showing a relief valve exhaust structure of a conventional cryopump. In the figure, (1) is the relief valve port, (2) is the duct connector, (3) is the screw that connects the relief valve port (1) and the duct connector (2), (4) is the exhaust duct, and (5) is the screw that connects the relief valve port (1) and the duct connector (2). ) is a relief valve with an inner cylinder (5a), an O-ring (5b), and a hole (5g
) with outer cylinder (5c), O-ring (5d), core (
5e) and a spring (5f).

Next, the operation will be explained.

Cryopumps move gas molecules to a cryogenic surface (below 20°K).
This is a storage vacuum pump (not shown) that does not have the usual exhaust to supplement the condensation or adsorption. Therefore, when it accumulates more gas molecules than it can, the temperature is raised to release the gas (this is called cryo-regeneration). At this time, the internal pressure of the pump increases, so it is necessary to release it as exhaust gas using the relief valve (5). In Figure 2, normally the point (X) on the cryo body side is in a vacuum state, and (Y)
) is the state of the atmosphere. The core (5e) is pressurized by a spring (5f), and the inner cylinder (5a) is sealed with an O-ring (5d) and an O-ring (5b).

Now, when the gas captured during cryo regeneration or abnormality is released, the internal pressure of the cryopump body increases and becomes a large value due to the atmospheric pressure plus pressurization of the spring (5f), the relief valve (5) The core (5e) moves against the spring (5f) and opens, gas flows along the arrow, and the outer cylinder (
5C) is discharged through the hole (5g).

At this time, foreign matter often gets caught in the O-ring (5d), causing a leak when the cryopump is operated again. At this time, loosen the four screws (3) and clean the inside of the relief valve (5). and screws (3
) and reassemble it.Also, when carrying out regular overhauls every 100,008 hours, remove the screws (3) and replace with the spare cryopump and reassemble.

[Problem to be solved by the invention] In the conventional cryopump relief valve exhaust structure as described above, the duct connector (2) is attached using the screw (3).
It is a little difficult to install the duct connector (2) because the screws (3) are lost, and the cryopumps are mixed with domestic and imported products, so the installation pitch is the same and the screw size is the same. Because the metric threads and inch threads are different, it is difficult to manage the threads, which can crush the threads of the female threads and cause poor tightening, resulting in the duct connector (2) not being completely fixed to the relief valve port (1), or in the worst case, tightening. There are cases where it is used with the relief valve (5) removed because it is troublesome to attach it, but in such a case, as long as the relief valve (5) is operating normally, there is no problem with the device. It is difficult to detect abnormalities in the tightening work because of the long intervals between periodic overhauls, and if the exhaust gas is harmful, it may fill the area around the exhaust bomb and cause a human accident.

This invention was made to solve the above-mentioned conventional problems, and provides a cryopump relief valve that allows the duct connector to be easily and securely attached to and removed from the relief valve port without tightening screws, and improves safety. The purpose is to obtain an exhaust structure.

[Means for Solving the Problems] In order to achieve the above object, a relief valve exhaust structure for a cryopump according to the present invention connects a relief valve for regenerating a Taraio bomb and this relief valve to the exhaust side of the cryopump. a relief valve port, a mounting seat formed integrally with the relief valve port or fixed with a screw, and a positioning pin protruding from a mating surface of the mounting seat;
a duct for discharging exhaust gas from the relief valve; a duct connector connected to the duct and having a pin hole on a mating surface into which the positioning pin is fitted; and a sealing material interposed between the mating surfaces; The relief valve port is equipped with a chest-type fixture that allows the duct connector to be attached and detached with a single touch.

[Function] In this invention, since the chest-type fixing device is provided, the duct connector can be attached to and detached from the relief valve port with one touch, and both are securely fixed.

[Embodiment 1] An embodiment of the present invention will be described with reference to FIG. FIG. 1 is a longitudinal sectional side view, and the same or corresponding parts as those of the conventional device are designated by the same reference numerals and the explanation thereof will be omitted. In the figure, (6) is the flange part (1a) of the relief valve port (1).
) is a mounting seat fixed by a screw (3), (7) is a positioning pin planted on the mating surface (6a) of the mounting seat (6),
(8) is a pin hole drilled in the mating surface (2a) of the duct connector (2), and is arranged to correspond to the positioning pin (7). (9) are both mating surfaces (2a), (6a
), (10) is a chest-type fixation device,
One hook-shaped member (10a) is attached to the outer peripheral surface of the mounting seat (6), and the other annular member (10b) is attached to the lever (10).
With the chest type fixing device (lO) attached to the outer circumferential surface of the duct connector (2) by c), the duct connector (2) can be connected to the relief valve port (1) by one-touch operation using the lever (10c). It can be attached and detached, and the two are firmly and securely fixed. When attaching the duct connector (2) to the relief valve port (1), the positioning pin (7) positions the duct connector (2), so the annular member (10) is attached to the hook-shaped member (10a).
The position of b) is automatically determined and does not interfere with the operation of the chest fixation device (10).

In the above embodiment, the mounting seat (6) is separately fixed to the flange portion (1a) of the relief valve port (1) with screws (3). It may be formed integrally with the port (1), that is, the flange portion (1a) may be used as the mounting seat (6).
In this case, the structure is simplified, the size is smaller, and work can be done reliably even in narrow spaces.

[Effects of the Invention] As described above, according to the present invention, a conventional relief valve port is used, and screws that cause trouble are not used for connection with the duct connector, so that the relief valve port of the duct connector can be connected to the relief valve port of the duct connector. The work of attaching and detaching the duct connector can be done easily, and any defects in the attachment of the duct connector can be eliminated, resulting in the effect of ensuring safety.

[Brief explanation of drawings]

FIG. 1 is a longitudinal side view showing an embodiment of the present invention, and FIG. 2 is a longitudinal side view showing a conventional relief valve exhaust structure. In the figure, (1) is the relief valve port, (2) is the duct connector, (2a) is the mating surface, (3) is the screw, and (4) is the duct connector.
) is the duct, (5) is the relief valve, (6) is the mounting seat, (
6a) is a mating surface, (7) is a positioning pin, (8) is a pin hole, (9) is a sealing material, and (lO) is a chest type fixture. Note that the same reference numerals in the figures indicate the same or corresponding parts.

Claims (1)

[Claims] (1) A relief valve for cryopump regeneration, a relief valve port that connects this relief valve and the exhaust side of the cryopump, a mounting seat formed integrally with this relief valve port or fixed with a screw, and this installation. a locating pin protruding from the mating surface of the seat; a duct for discharging exhaust gas from the relief valve; a duct connector connected to the duct and having a pin hole on the mating surface into which the locating pin is fitted; A relief valve exhaust structure for a cryopump, comprising a sealing material interposed between surfaces, and a hook-type fixture that allows the duct connector to be attached to and detached from the relief valve port with a single touch.