| 摘要 |
The invention relates to a control system for a percussion drive of an earth drilling unit having a housing, a drilling tool, a pulling or thrusting drive with pulling or thrusting means, a percussion piston, a pressure chamber belonging to the percussion piston and a pressure medium feed, which can be connected and disconnected, for the operation of the percussion piston, means being provided to connect and disconnect the pressure medium feed when the pulling or thrusting drive exceeds or falls below a specific pull or thrust.
|
