Abstract: A gas compressor includes a housing, a separating element in the housing, and a piston guided for movement along the separating element by a drive mechanism between two dead center positions. Gas is compressed in a three-stage compression cycle by the piston in three separate gas chambers arranged in series in the housing. Pressure increases in the gas are easily feasible from very low to very high pressures, for instance from 5 to 400 bar, based on a relatively small installation. The gas compressor includes only a few wear parts for low manufacturing and maintenance costs and for fail-safe operation.

Abstract: A cam plate is mounted on a drive shaft in a crank chamber. A plurality of pistons are operably coupled to the cam plate. The rotation of the drive shaft is converted to a linear reciprocal movement to compress and discharge refrigerant gas containing oil mist. An extracting passage extracts the refrigerant gas from the crank chamber to remove an excessive pressure in the crank chamber. The extracting passage is open to an accommodating chamber which receives the refrigerant gas from the passage. A bearing is disposed in the accommodating chamber and receives an axial load acting on the drive shaft. A bolt absorbs an assembly tolerance of the bearing. A first protuberance is provided on the bearing protruding in a radial direction with respect to the drive shaft so as to become aligned with the passage. The first protuberance engages an inner surface of the accommodating chamber to prevent rotation of the bearing.

Abstract: A pump apparatus includes a pump having a suction port and a discharge port for discharging the fluid sucked from the suction port, a return passage connecting the discharge port with the suction port for returning a portion of the fluid discharged from the discharge port into the suction port, a return flow control valve disposed in the return passage for controlling an amount of the portion of the fluid returned to the suction port through the return passage and an expanded chamber formed in the return passage and located between the suction port and the return flow control valve. The expanded chamber has a sectional area larger than that of the return passage.

Abstract: A linear peristaltic pump of the type for removable engagement of a portion of a flexible tubing and having a plurality of sequentially actuated pumping elements which act along the engaged portion of the flexible tubing, with the pumping elements reciprocated in a first direction to collapse adjacent segments of the tubing and then in a second direction to release the adjacent segments of the tubing, each pumping element reciprocated in a sequence so that fluid in the flexible tubing is moved along the engaged portion of the tubing. The linear peristaltic pump further comprises a plurality of reshaping fingers, with each of the reshaping fingers interposed adjacent to one of the pumping elements in sequence along the engaged portion of the flexible tubing.

Abstract: A pump utilizing a shape memory alloy member which is connected to electric terminals to be contracted by the supply of electric power for lowering a piston, the piston mounted to slidably move within a cylinder to thereby introduce a fluid into the cylinder is raised by a biasing force of a bias spring to externally discharge the fluid introduced in the cylinder. The pump has a simple structure which is light and easily repaired and maintained.

Abstract: Disclosed is a pump that employs a magnetic coupling to connect the motor to the impeller. A simplified structure within the pump casing is employed to enable the easy removal of the pump's impeller and bushings and/or bearings. In one embodiment of the invention, the exterior surface of the impeller, including its attached magnets, is encased in a plastic bushing material. Surrounding the impeller is a tubular bushing that may at times come into contact with the bushing material of the impeller.