Abstract: A pump that has a flangeless valve plate, meaning that the valve plate has no flange through which bolts that secure the head to the pump extend. The pump has eccentrics and pistons that all have holes in them so that the pistons at opposite ends of the pump can be assembled to the shaft of the motor 180° out of phase. The pump further has a monolithic head that includes the two head members of the pump and the tube that connects them also has an integrally formed port. The pump is supported by elastomeric tubular members from its ports. The pump has a push-in fitting that can be pushed into a hole in a member such as the head, the housing or the base so that once pushed in, a ring around the fitting expands outwardly behind an edge of the body to trap the fitting in the opening.

Abstract: A pump that has a flangeless valve plate, meaning that the valve plate has no flange through which bolts that secure the head to the pump extend. The pump has eccentrics and pistons that all have holes in them so that the pistons at opposite ends of the pump can be assembled to the shaft of the motor 180° out of phase. The pump further has a monolithic head that includes the two head members of the pump and the tube that connects them also has an integrally formed port. The pump is supported by elastomeric tubular members from its ports. The pump has a push-in fitting that can be pushed into a hole in a member such as the head, the housing or the base so that once pushed in, a ring around the fitting expands outwardly behind an edge of the body to trap the fitting in the opening.

Abstract: A compact 180° opposed piston pump/compressor minimizes axial spacing between its pistons on the drive shaft and thereby reduces the shaking couple and noise from reciprocation. Each piston has its own eccentric element press-fit into the connecting rods so as not to occupy space between the pistons. The shaking couple can be further reduced for pistons of different masses by selecting the mass of the cup retainers to compensate for the difference in overall piston masses. The pump also includes an improved cylinder sealing arrangement having a circumferential groove in an angled surface at the end of the cylinder. The pump also has a special cover and seal for closing the open neck of the pump crankcase and an improved multi-lobed valve stop. The pump further uses tubular transfer members for transferring intake and/or exhaust air into the crankcase and/or between valve heads.

Abstract: A compact 180° opposed piston pump/compressor minimizes axial spacing between its pistons on the drive shaft and thereby reduces the shaking couple and noise from reciprocation. Each piston has its own eccentric element press-fit into the connecting rods so as not to occupy space between the pistons. The shaking couple can be further reduced for pistons of different masses by selecting the mass of the cup retainers to compensate for the difference in overall piston masses. The pump also includes an improved cylinder sealing arrangement having a circumferential groove in an angled surface at the end of the cylinder. The pump also has a special cover and seal for closing the open neck of the pump crankcase and an improved multi-lobed valve stop. The pump further uses tubular transfer members for transferring intake and/or exhaust air into the crankcase and/or between valve heads.

Abstract: A compact 180° opposed piston pump/compressor minimizes axial spacing between its pistons on the drive shaft and thereby reduces the shaking couple and noise from reciprocation. Each piston has its own eccentric element press-fit into the connecting rods so as not to occupy space between the pistons. The shaking couple can be further reduced for pistons of different masses by selecting the mass of the cup retainers to compensate for the difference in overall piston masses. The pump also includes an improved cylinder sealing arrangement having a circumferential groove in an angled surface at the end of the cylinder. The pump also has a special cover and seal for closing the open neck of the pump crankcase and an improved multi-lobed valve stop. The pump further uses tubular transfer members for transferring intake and/or exhaust air into the crankcase and/or between valve heads.

Abstract: A wobble piston usable in a cylinder comprising one or both of the confronting surfaces of wobble piston head or valve plate being convexly curved in the plane of the wobble motion and being straight in a plane that is transverse to the plane of the wobble motion.

Abstract: Intake or exhaust reed valves of a compressor or vacuum pump have T-shaped flappers which are received in similarly T-shaped pockets so as to be substantially flush with the valve plate. A dirt trap groove is formed in each pocket adjacent to the hinge line of the flapper, a corner relief groove surrounds lands which support the flappers in their associated pockets above the groove, and the extending-part of each pocket widens in the direction away from the cross-part of the pocket. The mating T-shapes of a flapper in a pocket restrain the flapper in the pocket without interfering with the opening and closing motion of the flapper.

Abstract: A valve plate assembly includes a flapper valve and restraint in recessed intake and outlet ports of a valve plate. The recessed ports have guides located therein corresponding to notched sections of the flapper valve and the restraint such that a foolproof method of assembly can be achieved. In addition, a screw clearance in the top of the piston is not required since the recessed portion allows for the screw to be at or below the surface of the valve plate.