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. 25, 2006
Filed:
Jun. 18, 2001
Timo Muuttonen, Siuro, FI;
Pekka Salminen, Tampere, FI;
Timo Muuttonen, Siuro, FI;
Pekka Salminen, Tampere, FI;
Sandvik Intellectual Property AB, Sandviken, SE;
Abstract
A rock drill includes a string of components interconnected by screw threads and connected to a shank. A percussion piston is reciprocated against the shank during a drilling operation, while a support device applies axial support to the rear of the shank, to enhance the drilling action. When the components are being unscrewed, the percussion piston is actuated to strike the rear end of the drill string, after the support device has at least partially released the axial support of the shank, to enable tensile stress to be generated in the components by the percussive impacts to facilitate unscrewing of the components.