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:
Apr. 10, 2001
Filed:
Mar. 19, 1999
Hirokatsu Kohsokabe, Ibaraki-ken, JP;
Masahiro Takebayashi, Tochigi-ken, JP;
Shunichi Mitsuya, Shizuoka-ken, JP;
Hiroaki Hata, Tochigi-ken, JP;
Yasuhiro Ohshima, Tochigi-ken, JP;
Kenji Tojo, Ibaraki-ken, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A conventional displacement type fluid machine is featured by a low sliding rate and in low vibrations and pulsations, but has a problem, that the radial gap in a displacer sliding portion is enlarged by the clearance of a shaft drive system and a rotating moment acting on a displacer so that the internal leakage of a working fluid is increased to lower the performance and the reliability. To eliminate this problem, the sliding contact portion between a cylinder,and a displacer,is made into a predetermined section, and the cylinder and the displacer are so contoured that when they are made concentric, the normal distance in the sliding contact section between the cylinder contour and the displacer contour may be smaller than that of the remaining section, thereby to decrease the radial gap to lower the internal leakage of the working fluid and to improve the performance and the reliability.