Suction and discharge valve mechanism for fluid displacement apparatus

摘要

A piston-type fluid displacement apparatus includes a housing enclosing a crank chamber, a suction chamber, and a discharge chamber. Discharge conduits are formed at a top dead center position of the piston. A control device includes valve members having suction apertures and discharge apertures for opening and closing the suction conduits and the discharge conduits. The control device further includes a driving mechanism joined to the valve members for driving the valve members to gradually open each of the suction conduits during the suction stage of the piston and to gradually close each of the discharge conduits during the discharge stage of the piston. Thus, the piston-type fluid displacement apparatus may prevent the valve assembly from stopping or sticking at the sliding contact surfaces of the suction and discharge holes to allow the pistons to reciprocate smoothly within each cylinder without reducing the compression efficiency. Further, the piston-type fluid displacement apparatus also improves the sealing performance between the valve assembly and the sliding contact surfaces of the suction and discharge holes.