| 摘要 |
PCT No. PCT/SE93/00943 Sec. 371 Date Jul. 7, 1995 Sec. 102(e) Date Jul. 7, 1995 PCT Filed Nov. 9, 1993 PCT Pub. No. WO94/11160 PCT Pub. Date May 26, 1994A pressure medium operated reciprocating impact mechanism has at least one working member (7) and at least one stop member (15), which are axially movable with respect to each other, and a working chamber (22) for pressure medium is arranged in at least one of them and is opened towards the other member. One of the members has an opening (39) emerging into the working chamber for feeding pressure medium to the working chamber. The impact mechanism comprises an arrangement (21) for sealing the working chamber in the position in which the members are brought most together and allow pressure medium to escape out of the working chamber when a predetermined relative position of the members is reached during their movement apart. Furthermore, the impact mechanism comprises members (34, 35, 36) adapted to be actuated by the relative movement of the stop member and the working member and by this actuation during the movement of these members apart arrive to a state in which they obstruct the supply of compressed medium to the chamber and allow the supply during the movement of these members towards each other. |
