| 摘要 |
Reciprocating drive means powered by a fluid such as compressed air comprising an elongate inner member (1) with a plurality of passageways (A to E) therein, an outer member (2) slidable on the inner member and a shuttle member (3) slidable with respect to the inner member and within the outer member, the passageways in the inner member being variously and intermittently so connected in use, by ports (a1 to e2) in the inner member, to each other by way of compartments (23 and 26 to 29) provided within the outer member and the shuttle that, upon connection of a determined one (1) of said passageways to a fluid pressure source or a vacuum source, the outer member (2) moves with reciprocating action with respect to the inner member. The elongate inner member has two fixed discs (11,12) thereon, between which discs the shuttle member (3) oscillates the discs having seals on their peripheral surfaces to seal against the inner wall of the outer member, the outer member is cylindrical with end walls (15,16) having seals alidable on the elongate inner member and cooparating with ports (d1 and e2) therein respectively and the shuttle member has axially spaced seals on its inner peripheral surface to cooperate with ports (b1 and c1) in the inner member and to seal against the elongate member and define one (23) of the compartments therebetween. Following movement of the outer member (2) in one direction, the shuttle member (3) is moved by pressure in an opposite direction to cause the outer member (2) to move in said opposite direction. |
