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:
Oct. 31, 1989
Filed:
Jun. 24, 1988
Peter J Taylor, Hants, GB;
Plessey Overseas Limited, Ilford, GB;
Abstract
A rotary pump system for pumping a liquid which is delivered under pressure from a backing pump 8, in which a rotary pump 1 has a pump body which is required to be drained of liquid at times when the pump 1 is inoperative, wherein the backing pump 8 has a by-pass circuit between its inlet and outlet ports, the by-pass circuit comprisng a multiphase pump 13 which has a suction inlet 14 connected to a drain point 16 on the pump 1 body and a vortex chamber 17 through which liquid passes from the pump 13 outlet to the backing pump 8 inlet, a central outlet 18 of said vortex chamber being connected to an inlet port 6 of said pump 1. This allows automatic draining of the pump 1 body when use of this pump is not required.