Arrangement in a hydraulically operated rock drilling equipment
Number of patents in Portfolio can not be more than 2000
United States of America Patent
Stats
-
Jul 14, 1998
Grant Date -
N/A
app pub date -
Oct 4, 1996
filing date -
Apr 14, 1994
priority date (Note) -
Expired
status (Latency Note)
Importance
Abstract
Arrangement in a hydraulically operated rock drilling equipment comprising a feed motor (3), a percussion device (2), and a hydraulic pump (1) for feeding hydraulic fluid to the feed motor (3) and the percussion device (2). The arrangement comprises a pressure control valve (17) connected to be controlled on the basis of the control signal of the feed regulation valve (8) when starting the drilling so that when the value of the control signal is below a predetermined switching value, the pressure relief valve (18) is connected to the percussion pressure line (13) of the percussion device (2), and when the control signal exceeds the switching value, the pressure control valve (17) disconnects the pressure relief valve (18) from the percussion pressure line (13) and connects the pressure difference valve (20) in communication with the percussion pressure line (13).
First Claim
Other Claims data not available
Family
International Classification(s)
Cited Art Landscape
Patent Citation Ranking
- 11 Citation Count
- E21B Class
- 52.49 % this patent is cited more than
- 27 Age