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:
Aug. 17, 1982
Filed:
Sep. 19, 1979
Gert Herrmann, Solingen, DE;
Pierburg Luftfahrtgerate Union GmbH, Neuss, DE;
Abstract
A self-sealing gear pump has seals formed between the end faces of the gear wheels and adjacent faces of a casing of the pump by thrust plates interposed between the end faces of gear wheels and the casing. The thrust plates have cavities formed behind them and are pressed against the end faces by the pumped fluid under pressure being admitted to the cavities. Each cavity is connected to both the high pressure side of the pump and the low pressure side of the pump by ports or nozzles, the flow section of the nozzle leading to the high pressure side being larger than that of the nozzle leading to the low pressure side. The surface area of each thrust plate exposed to its cavity is greater than its surface area exposed to the high pressure side of the pump and each cavity and the fluid connections to it are constructed as a hydraulic potentiometer which causes the pressure in the cavity and hence the sealing pressure of the plate against the gear wheels to be adjustable.