Global Patent Index - EP 0370117 B1

EP 0370117 B1 19940112 - Two-shaft vacuum pump and method of operation.

Title (en)

Two-shaft vacuum pump and method of operation.

Title (de)

Zweiwellenvakuumpumpe und Verfahren zu ihrem Betrieb.

Title (fr)

Pompe à vide avec deux arbres et méthode de fonctionnement.

Publication

EP 0370117 B1 19940112 (DE)

Application

EP 88117650 A 19881024

Priority

EP 88117650 A 19881024

Abstract (en)

[origin: JPH02153291A] PURPOSE: To effect pump scavenging reasonably by supplying scavenging gas to a suction volume transported to an opening of a scavenging gas conduit after an inlet opening of the vacuum pump is closed, and effecting supply control by using the rotors at the outlet side of the rotor pairs. CONSTITUTION: In a three-staged vacuum pump 1 with three pairs of rotors 6, 7 arranged axially on two shafts 2, 3, each pair of rotors 6, 7 comprises a protrusion 38 and a notch 39 respectively supported in a suction chamber 12 for rotating synchronously in a non-contact manner. The rotors 6 are controlled by an inlet opening 35 and the other rotors 7 are controlled by an outlet opening 42. In this case, scavenging gas (nitrogen gas, etc.), is supplied into a suction volume 44 transported to an opening 45 of a scavenging gas conduit leading to a gas bomb after the inlet opening 35 is closed. After that, the outlet opening 42 is opened, the supply of scavenging gas is controlled by using the rotors at the outlet side.

IPC 1-7

F04C 29/00; F04C 23/00

IPC 8 full level

F04C 25/02 (2006.01); F04C 29/00 (2006.01)

CPC (source: EP US)

F04C 18/123 (2013.01 - EP US); F04C 23/001 (2013.01 - EP US); F04C 29/0007 (2013.01 - EP US); F04C 2220/12 (2013.01 - EP US)

Designated contracting state (EPC)

CH DE FR GB LI

DOCDB simple family (publication)

EP 0370117 A1 19900530; EP 0370117 B1 19940112; DE 3887149 D1 19940224; JP 2755733 B2 19980525; JP H02153291 A 19900612; US 5049050 A 19910917

DOCDB simple family (application)

EP 88117650 A 19881024; DE 3887149 T 19881024; JP 27511889 A 19891024; US 48215190 A 19900220