Abstract: A pump apparatus is provided which comprises a first displacement pump and a ceramic valve construction formed of a ceramic rotor, a ceramic stator having flat surfaces which are positioned in sealing relationship and a second displacement pump having check valves. The first displacement pump comprises a reciprocating first piston within a housing having an interior wall spaced apart from the piston. The position of the first piston and the position of the rotor are controlled to effect desired fluid flow through the stator. The first piston and a second piston of the second displacement pump are reciprocated by a common motor.

Abstract: A pump apparatus is provided which comprises a plurality of displacement pumps each connected to a check valve apparatus. The displacement pumps each comprises a reciprocating piston within a housing having an interior wall spaced apart from the piston. The check valve apparatus comprises two check valves that control fluid flow under pressure exerted by the reciprocating piston from a fluid reservoir to a point of use of the fluid. Pistons of the displacement pumps are driven by a common motor.

Abstract: A pump apparatus is provided which comprises a displacement pump and a check valve apparatus. The displacement pump comprises a reciprocating piston within a housing having an interior wall spaced apart from the piston. The check valve apparatus comprises two check valves that control fluid flow under pressure exerted by the reciprocating piston from a fluid reservoir to a point of use of the fluid.

Abstract: A pump apparatus is provided which comprises a plurality of displacement pumps each connected to a check valve apparatus. The displacement pumps each comprises a reciprocating piston within a housing having an interior wall spaced apart from the piston. The check valve apparatus comprises two check valves that control fluid flow under pressure exerted by the reciprocating piston from a fluid reservoir to a point of use of the fluid. Pistons of the displacement pumps are driven by a common motor.

Abstract: A pump apparatus is provided which comprises a first displacement pump and a ceramic valve construction formed of a ceramic rotor, a ceramic stator having flat surfaces which are positioned in sealing relationship and a second displacement pump having check valves. The first displacement pump comprises a reciprocating first piston within a housing having an interior wall spaced apart from the piston. The position of the first piston and the position of the rotor are controlled to effect desired fluid flow through the stator. The first piston and a second piston of the second displacement pump are reciprocated by a common motor.

Abstract: A door closing device including closing means for urging a door between said first open position and second closed position having a cable mounted in a housing said cable wound about periphery of a reel regulating the speed of movement of said door between the open position and closed position; a reservoir for containing viscous fluid; and a buffer for retarding the speed of movement of said door comprising an impeller immersed in the viscous fluid for use as a brake; whereby the impeller reduces rotational speed of said reel, thus reducing closing speed of said door.