Heavy-calibre cryopump for pumping away xenon

Abstract

The invention discloses a heavy-calibre cryopump for pumping away xenon. By means of the cryopump, the xenon can be pumped away at the high pumping speed, and the device is sputtering-resistant and free of oil vapor pollution. The cryopump comprises a cryo refrigerator, an absorption array, a thermal shroud, a radiation protection screen, a pump casing, a baffle, a baffle temperature measurer, an absorption array temperature measurer and a first-grade cold shield, wherein the absorption array is composed of multiple oblong shells, the upper surface and the lower surface of each oblong shell are open, and fins are arranged on the side faces of each oblong shell; the baffle is fixedly installed on the thermal shroud at a cryopump opening, the baffle is of a plate-shaped structure, the primary optical shielding is achieved for the absorption array in the perpendicular direction of the baffle, and a graphite coating is sprayed on the surface of the baffle. The cryopump is capable of pumping away the xenon at the pumping speed which is one and a half times of that of a common cryopump, no pollution is caused, the sputtering resistance is achieved, the cryopump is applicable to an severe environment of high temperature plasma, and liquid nitrogen or mechanical refrigerant can be adopted for refrigeration so that the cost can be lowered.

Description

technical field [0001] The invention relates to the technical field of vacuum pumping, in particular to a cryogenic pump for pumping xenon gas with a large diameter. Background technique [0002] The performance or reliability test of a large xenon working medium thruster needs to be tested in a high vacuum environment, and the baffle of the pump body is easily corroded by the thruster beam sputtering, which affects the performance of the thruster and cryopump. Moreover, during the test of the xenon gas thruster, the amount of gas released is large, ranging from a few sccm to hundreds of sccm, which requires a high-vacuum pump with a strong xenon pumping capacity. In the past, oil diffusion pumps were generally used to pump xenon. , but on the one hand, the diffusion pump will bring oil vapor pollution to the test, and the diffusion pump can only be installed vertically, and the vertical installation position on the test container is very limited. With the rapid development...

AI Technical Summary

Problems solved by technology

However, the current common large-diameter cryopumps are all designed for pumping out air, and their pumping speed for xenon gas is relatively small, and the front baffle cannot withstand long-term ion thruster beam sputtering

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