Reciprocating device and switching mechanism therefor.

摘要

A reciprocating device comprising a housing (13) having a chamber (15) and a reciprocable member (17) reciprocable in the chamber. First and second pressure valves (117 and 119) are connectible to a source of fluid under pressure (32) to drive the reciprocable member and first and second passages (95 and 97) lead from the first and second pressure valves (117 and 119) to the chamber (43 and 45) on opposite sides of the reciprocable member (17), respectively. First and second exhaust valves (113 and 115) are coupled, respectively to the first and second passages (95 and 97) at locations intermediate the associated pressure valve (117 and 119) and the chamber (43 and 45) and communicating with first and second vents (34 and 36), respectively. Actuators (75 and 77) are drivable by the reciprocable member (17) for switching the valves between first and second positions, and the fluid under pressure retains the valves in whichever of the positions they are placed.