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:
Mar. 20, 1990
Filed:
Nov. 01, 1988
Max Co., Ltd., Tokyo, JP;
Abstract
A percussion tool of the repeatedly operating type includes a housing, a striking cylinder received in the housing for movement therealong, and a driving piston received in the striking cylinder for movement therealong. The striking cylinder cooperates with the housing to provide a switch valve means which is responsive to the movement of the striking cylinder along the housing for selectively interrupting fluid communication between the interior of the striking cylinder and a discharge port and communicating the interior of said striking cylinder with a compressed air source when the striking cylinder is at its lower position to thereby move the striking piston to cause an associated striking driver to strike a driven element and for selectively interrupting the communication between the interior of the striking cylinder and the compressed air source and communicating the interior of the striking cylinder with the discharge port as the striking cylinder is moved from its lower to upper position. Air within that portion of the interior of the striking cylinder between a lower face of the driving piston and a lower end of the striking cylinder is compressed by the striking piston moving toward an ejecting portion receiving the driven element and is supplied to a return air chamber. The air thus compressed acts on the lower face of the piston to urge the same away from the ejecting portion.