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:
Jan. 14, 2003
Filed:
Mar. 28, 2001
Applicant:
Inventors:
Tapani Pöysti, Tampere, FI;
Jaakko Niemi, Tampere, FI;
Reijo Rämö, Toijala, FI;
Timo Muuttonen, Siuro, FI;
Assignee:
Sandvik Tamrock Oy, , FI;
Primary Examiner:
Int. Cl.
CPC ...
E21B 4/400 ;
U.S. Cl.
CPC ...
E21B 4/400 ;
Abstract
The invention concerns an arrangement for controlling a hydraulic rock drilling device. The arrangement includes a pressure ratio valve that is used for adjusting the relation between the pressures in the pressure channel leading to the percussion device and/or another actuator, such as a shank stabilizer, and the pressure channel leading to the feed mechanism. The pressure ratio valve is arranged to keep the relation between the pressures of the actuator and the feed mechanism constant over the normal drilling range.