Title:
VACUUM PUMP AND STATIONARY DISK PROVIDED IN VACUUM PUMP
Document Type and Number:
WIPO Patent Application WO/2018/061577
Kind Code:
A1
Abstract:
[Problem]
To alleviate the occurrence of localized high pressure in a helical plate in a vacuum pump.
[Solution]
A vacuum pump wherein holes are formed in a stationary disk, and the ratio of holes at the front edge (outer circumferential side/outer circumferential portion) of the stationary disk locally increases. More specifically, (1) holes of substantially the same size are arranged in parallel from the inner circumferential side of the stationary disk to the outer circumferential side, and the number of holes arranged in the outermost row is greater than in the innermost row, (2) holes of substantially the same size are arranged in parallel from the inner circumferential side of the stationary disk to the outer circumferential side, and a number of the holes arranged in the outermost row are joined to form a single hole, (3) T-shaped holes are arranged on the stationary disk, or (4) L-shaped holes are arranged on the stationary disk. By means of these configurations a high-pressure section is not likely to occur near the front edge of a helical plate, so it is possible to reduce deposition of reaction products due to liquefied or solidified gas.
Inventors:
KABASAWA TAKASHI (JP)
Application Number:
PCT/JP2017/030977
Publication Date:
April 05, 2018
Filing Date:
August 29, 2017
Export Citation:
Assignee:
EDWARDS JAPAN LTD (JP)
International Classes:
F04D19/04
Domestic Patent References:
| WO2009028099A1 | 2009-03-05 |
Foreign References:
| JP2015505012A | 2015-02-16 | |||
| JP2002285988A | 2002-10-03 | |||
| JPS5138113A | 1976-03-30 | |||
| JPS60188892U | 1985-12-14 |
Other References:
See also references of EP 3521629A4
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