摘要 |
<p>A pulse drilling machine (1;1′) for the generating of shock wave pulses in a tool direction (R) has an impulse piston (4;4′) with a housing (2), and a device (8) for abruptly changing fluid pressure influencing the impulse piston to achieve a force resultant on the impulse piston in the tool direction to generate a shock wave pulse in a drill string (13; 13′) which is connected to the machine, a first fluid chamber (14;3′) inside the housing which in operation is arranged to exert a pressure in the tool direction on the impulse piston. The machine has a fluid flow channel (11; 18; 19), which includes a device for damping fluid flow flowing from the first fluid chamber through the fluid flow channel obtained when influencing the impulse piston (4; 4′) in a direction opposite to the tool direction (R) by rock reflexes in the drill string during drilling.</p> |