The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 17, 1991
Filed:
Feb. 20, 1990
Hanns-Peter Berges, Cologne, DE;
Wolfgang Leier, Bergisch-Gladbach, DE;
Leybold Aktiengesellschaft, , DE;
Abstract
The invention is directed to a method for the operation of a twin shaft vacuum pump (1) having two rotors (4, 5; 6, 7; 8, 9) that rotate synchronously and in non-contacting fashion in a pump chamber, each being provided with a respective projection (38) and a recess (39), the one of said rotors controlling an admission opening (32, 35) and the other controlling a discharge opening (33, 37, 42); the invention is also directed to a twin shaft vacuum pump suitable for the implementation of the method; in order to be able to admit flushing gas into a twin shaft vacuum of this species during operation as well, it is proposed that flushing gas be admitted into the respectively diminishing pump volume via an orifice (45) that is controlled such by the rotor at the discharge side that the respective pump volume is closed both toward the admission opening (35) as well as toward the discharge opening (42) at the moment the flushing gas is supplied.