| 摘要 |
The invention concerns an apparatus comprising a body ( 1 ) containing a cylinder wherein is mounted sliding an impact piston ( 1 ) of a tool, the motion of the piston being controlled by a distributor ( 15 ) which, arranged coaxial to the impact piston, is mounted inside a distribution box ( 3 ). The distribution box ( 3 ) comprises a part axially overlapping the piston ( 1 ) and arranged concentric thereto, and the distribution box ( 3 ) defines with the piston a control chamber ( 13 ) which, successively put under the high ( 9 ) and the low ( 12 ) pressure of the fluid, communicates through a passage ( 16 ) arranged in the distribution box ( 3 ) with a chamber controlling ( 14 ) the movement of the distributor ( 15 ), to generate alternately low pressure and high pressure. |
