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:
May. 29, 1979
Filed:
Sep. 09, 1977
Applicant:
Inventors:
Thomas W Weisgerber, Saginaw, MI (US);
Brian K Nelson, Frankemuth, MI (US);
Richard P Riefel, Saginaw, MI (US);
Assignee:
General Motors Corporation, Detroit, MI (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
F01M / ;
U.S. Cl.
CPC ...
1231 / ;
Abstract
An engine driven vacuum pump combining a two-stage, low noise demountable pump assembly with a camshaft driven eccentric drive arrangement having internal oil distribution and pumping means for lubricating the drive and pump pushrod elements. A check valve in the cover of the pump assembly defines a second stage pumping chamber which increases pump efficiency while at the same time cyclically closing the pump outlet to reduce external noise attributable to gas discharge from the primary pumping chamber.