VACUUM PUMP - EDWARDS JAPAN LTD

Title:

VACUUM PUMP

Document Type and Number:

WIPO Patent Application WO/2010/007975

Kind Code:

A1

Abstract:

Provided is a vacuum pump which can detect precisely the physical contact between a rotary portion and a stationary portion and the arrival of the accumulation of a solid product at the clearance between the rotary portion and the stationary portion. A vibration sensor is mounted by making use of a clearance on the outer circumference of a thread groove spacer. The occurrence of a contact between the rotary portion and the stationary portion is decided, if specific vibrations to be caused by the contact between the rotary portion and the stationary portion exceed a predetermined threshold level. The vibration sensor is mounted on the outer circumference of the thread groove spacer at the end of the side of an exhaust port. The thread groove spacer is fixed on an armor through an elastic member (an O-ring) having attenuating characteristics of a cut-off frequency (fc1). A vibration signal outputted from the vibration sensor is converted into a digital vibration signal, and is inputted to a digital filter having a passing band of fc1 to fc2 [Hz]. If the vibration level of the vibration signal having passed through the digital filter exceeds a predetermined threshold value, it is detected that the contact between the rotary portion and the stationary portion has occurred in a turbo-molecular pump.

Inventors:

OHTACHI YOSHINOBU (JP)
NONAKA MANABU (JP)
MAEJIMA YASUSHI (JP)

Application Number:

PCT/JP2009/062708

Publication Date:

January 21, 2010

Filing Date:

July 14, 2009

Export Citation:

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Assignee:

EDWARDS JAPAN LTD (JP)
OHTACHI YOSHINOBU (JP)
NONAKA MANABU (JP)
MAEJIMA YASUSHI (JP)

International Classes:

F04D19/04

Foreign References:

JPH06330885A	1994-11-29
JP2003097554A	2003-04-03
JP2004150340A	2004-05-27
JPH06330885A	1994-11-29
JPH06101655A	1994-04-12
JP2004117091A	2004-04-15

Other References: