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:
Jul. 07, 1998
Filed:
Aug. 31, 1995
Isamu Tanji, Hitachinaka, JP;
Yoshinori Ishizawa, Hitachinaka, JP;
Hitachi Koko Co., Ltd., Tokyo, JP;
Abstract
A percussion tool comprises a cylinder 3 communicated to a pressure accumulating chamber 16 storing pressurized air therein, and a piston 4 slidable in the cylinder 3 when pressurized air is introduced into the cylinder 3 from the pressure accumulating chamber 16 and pressure of the introduced air is applied on the piston 4. A circular groove 6 is recessed on a peripheral surface of the piston 4, the peripheral surface adjacently facing to an inside wall of the cylinder 3. A piston ring 10 is accommodated in the circular groove 6, so as to provide a hermetical sealing between the piston 4 and the cylinder 3. And, a ring bumper 11 made of resilient member is provided in the circular groove 6 adjacent to the piston ring 10 in a sliding direction of the piston 4.