Patent ID: 6012905
Filing Date: 2000-01-11
Classification: F04B

Abstract:
A piston-type fluid displacement apparatus comprising:a housing enclosing a crank chamber, a suction chamber, and a discharge chamber;a plurality of cylinders formed inside said housing;a plurality of pistons, wherein each piston is slidably disposed within one of said cylinders such that said piston reciprocates within said cylinder;a plurality of suction conduits formed at a top dead center position of said piston;a plurality of discharge conduits formed at said top dead center position of said piston;a drive shaft rotatably supported in said housing, wherein said drive shaft is coupled to said pistons for driving said pistons, such that a rotary motion of said drive shaft is converted into a reciprocating motion of said pistons within said cylinders; andcontrol means comprising a plurality of valve members, each valve member having a suction aperture and a discharge aperture for opening and closing said suction conduit and said discharge conduit, wherein said control means further comprises a driving mechanism connected to said valve members for driving said valve members to gradually open each of said suction conduits during a suction stage of said piston.