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. 05, 2005
Filed:
Oct. 19, 2001
Yoshiaki Ogura, Sakai, JP;
Yoshiaki Ogura, Sakai, JP;
Sharp Kabushiki Kaisha, Osaka, JP;
Abstract
A free-piston type Stirling engine used for producing cold heat with the vibration center position of a piston accurately kept. A first space is formed on one side of a piston, and a second space is formed on the opposite side to spread up to a portion adjacent to a cylinder's side wall. A piston is provided with a vibration-direction first groove extending up to the first space and a circumferential-direction second groove, and a cylinder is provided with a hole penetrating the side wall thereof. The second groove of the piston, when coupled with the cylinder's hole during a piston vibration process, allows the first space to communicate with the second space. Accordingly, a short-time communication between the first and second spaces will balance pressures in the two spaces against each other to keep the vibration center position of the piston accurately.