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:
Jan. 08, 2002
Filed:
May. 22, 2000
Shinichi Fujii, Obu, JP;
Seiji Murase, Obu, JP;
Aisan Kogyo Kabushiki Kaisha, Aichi-Ken, JP;
Abstract
An impeller has a plurality of blade grooves formed along a perimeter thereof. A pump casing has an inlet port , a discharge port , a first circumferential groove contiguous with the inlet port , a second circumferential groove contiguous with the discharge port and a partition between a groove inlet portion and the discharge port . An opening end face of the discharge port on the side of the pump casing that faces the impeller has a tapered portion and a damping portion . The tapered portion has an opening width W that gradually decreases along the direction of rotation of the impeller . The damping portion has an opening width that is substantially constant along the direction of rotation of the impeller. In one embodiment, a corner portion, which is defined by wall surfaces defining the tapered portion and the damping portion of the discharge port , respectively, and a lower surface of the pump casing , is chamfered.