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.

Date of Patent:
Jul. 15, 2008

Filed:

Jul. 14, 2004
Applicants:

Kazuyoshi Uchino, Saitama, JP;

Shigeyuki Miyazawa, Saitama, JP;

Inventors:

Kazuyoshi Uchino, Saitama, JP;

Shigeyuki Miyazawa, Saitama, JP;

Assignee:
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
F04B 49/00 (2006.01); F04B 1/06 (2006.01);
U.S. Cl.
CPC ...
Abstract

A variable displacement pump includes a control valve formed with a high-pressure chamber for introducing therein high-pressure fluid on the upstream side of a metering orifice, a pressure chamber for introducing therein pressure fluid on the downstream side of the metering orifice, a low-pressure chamber arranged between the high-pressure and pressure chambers for introducing therein low-pressure fluid, and a communication passage for providing fluid communication between one of the high-pressure and low-pressure chambers and a first fluid-pressure chamber of the pump. First and second recessed grooves are formed in the outer-peripheral surface of a spool of the control valve to provide fluid communication between the low-pressure and high-pressure chambers through the communication passage of the control valve when the spool carries out selective switching between the high-pressure and low-pressure chambers to supply fluid to the communication passage, thus restraining abrupt pressure rise in the first fluid-pressure chamber.


Find Patent Forward Citations

Uchino, Kazuyoshi. (2008). Variable displacement pump (U.S. Patent No. 7399166). U.S. Patent and Trademark Office. https://idiyas.com/patent/badge/7399166

Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile

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