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:
Dec. 13, 1994
Filed:
Jun. 14, 1993
Applicant:
Inventor:
Kurt Andersson, Tyreso, SE;
Assignee:
Atlas Copco Rocktech AB, Stockholm, SE;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
E21B / ;
U.S. Cl.
CPC ...
175296 ; 173 78 ; 173 91 ; 173112 ;
Abstract
Hammer device comprising a machine housing (1) with a hammer piston (2) movable to-and-fro. The movement to-and-fro of the hammer piston is controlled by a valve body (6) movable to-and-fro in the machine housing. In order to speed up the turning of the hammer piston at its rear end position the machine housing is provided with a room (10) which by the hammer piston is separated from connection with the valve body (6) at the same time as the rear end surface (5) is supplied with pressure fluid via a connection (11) opened by the hammer piston to the pressure source (8) when the hammer piston approaches its rear end position.