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. 16, 2012
Filed:
Aug. 24, 2009
Hironao Yokoi, Aichi-ken, JP;
Shigeru Suzuki, Aichi-ken, JP;
Katsumi Yamashita, Aichi-ken, JP;
Toshiro Fujii, Aichi-ken, JP;
Hironao Yokoi, Aichi-ken, JP;
Shigeru Suzuki, Aichi-ken, JP;
Katsumi Yamashita, Aichi-ken, JP;
Toshiro Fujii, Aichi-ken, JP;
Abstract
A variable displacement rotary pump includes a main pump unit, an auxiliary pump unit, a discharge passage, a bypass passage, a suction passage, a check valve and a control valve. The suction passage is in communication with the discharge passage through the bypass passage and a second discharge port. The check valve is disposed in the discharge passage for preventing fluid in a first discharge port of the main pump unit from flowing into the bypass passage. The control valve is operable for opening and closing the bypass passage. When the control valve opens the bypass passage and the check valve closes the discharge passage, flow rate of the fluid discharged from the discharge passage is reduced. A throttle passage is provided in the bypass passage or the control valve for regulating flow of the fluid in early phase of operation of the control valve to open the bypass passage.