Percussion mechanism

Abstract

The fluid-actuated percussion mechanism includes a housing with an internal ylindrical space wherein a reciprocating piston, which divides the space into a working stroke chamber and an idle stroke chamber, is received. The mechanism further includes fluid distributing means and a distribution unit mounted in the housing for placing the chambers and a source of the working fluid in communication. The housing also accommodates a work-performing member adapted to receive impacts from the piston. The distribution unit includes at the inlet of at least one of the chambers a valve made in the form of a resilient annular element. The surface of the distribution unit has valve seats made in it, the number of which corresponds to that of the inlets for supplying the working fluid into the chambers. The resilient valve element is taut about the surface of the distribution unit in opposition to the inlets and encircles the periphery of the unit. The internal surface of the resilient element with the valve seat and the external surface of the resilient element with the housing each define at least one inlet passage for supplying the working fluid to the inlets. The disclosed structure of the valve, of the distribution unit and of the housing enables an increase in the total flow area of the passages through which the working fluid is supplied to the inlets of the chambers and thus an increase in the power output of the percussion mechanism.