Valve for pneumatic drill - has inset trigger displacing piston rod which pivots conical plug located in air feed pipe

摘要

The trigger-operated valve may be incorporated in the handle (3) of a pneumatic drill and controls the incoming supply (25) of compressed air. The handle is of deformable material and has a slot-mouthed cavity (5) locating the trigger (6). The trigger floats and pivots within the cavity, is forcefully installed through the slot-mouth, and is depressed to displace a piston rod (8) which pivots a plug (10). The plug may be of a truncated cone form and locates in the feed pipe (9) at an axial reduction in dia. effected by a radial step. The plug end of largest dia. has a concentric demi-round section circular lip (14) which bears on the annular faces of the step to seal the inlet (15).