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:
May. 25, 2010
Filed:
Mar. 09, 2007
Isamu Tsubono, Ushiku, JP;
Mitsuo Sasaki, Hatano, JP;
Toru Takahashi, Hiratsuka, JP;
Masaaki Busujima, Atsugi, JP;
Masakazu Kurata, Yokohama, JP;
Yasuhito Nakakuki, Atsugi, JP;
Isamu Tsubono, Ushiku, JP;
Mitsuo Sasaki, Hatano, JP;
Toru Takahashi, Hiratsuka, JP;
Masaaki Busujima, Atsugi, JP;
Masakazu Kurata, Yokohama, JP;
Yasuhito Nakakuki, Atsugi, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
In order to realize cost reduction in a gear pump apparatus by reducing form accuracy of a gear while securing pump performance, a running-in coating is provided on a tooth sliding contact portion when forming a confinement area in at least one of gears of the gear pump apparatus. By this feature, the running-in coating is gradually worn away and deformed according to rotary drive of the pump, and thus it is possible to obtain an optimal gear form in meshing combinations of the gears. Further, it is possible to reduce leakage inside the pump to secure the pump performance even if the form accuracy of the gear is reduced for the sake of the cost reduction.