A screw rotor is made out of polymer. The screw rotor includes a shaft with a rotor body on it. The polymer of the shaft is reinforced with fibers. The shaft features elements that engage the rotor body or corresponding elements on the rotor body, such that the elements prevent an axial and/or rotational movement of the shaft with respect to the rotor body.

A device and method coupled to a therapy garment to apply pressure and repetitive compression forces to a body of a person has a positive air pulse generator and a user programmable time, frequency and pressure controller operable to regulate the duration of operation, frequency of the air pulses and a selected air pressure applied to the body of a person. The air pulse generator has rigid displacers that are angularly moved with power transmission assemblies to draw air into the air pulse generator and discharge air pressure pulses to the therapy garment.

A vane assembly for use in a rotary vane actuator, the vane assembly comprising: a rotatable vane having a first side and a second side; a vane axle connected to the rotatable vane for converting pressure exerted on the rotatable vane into rotational motion; a vane seal on the first side of the rotatable vane, the vane seal being for sealing the rotatable vane; and a side-plate on the first side of the rotatable vane, the side-plate clamping the vane seal in position; wherein the side-plate comprises: an outer part providing an outer surface of the side-plate, the outer part defining an internal volume; and an inner part filling or substantially filling the internal volume defined by the outer part, the inner part being distinct from the outer part.

The present invention relates to an apparatus for pumping or compressing a fluid, the apparatus characterized by a compression chamber including an inlet and outlet, opposed front and rear vane members disposed inside said compression chamber, each vane member including at least one axially extending vane segment and at least one radially disposed open segment adapted to receive a vane segment of the opposed vane member, wherein adjacent vane segments of mating vane members form radial compartments there between. The assembly further includes a swing arm assembly for effecting equal and opposite rotational oscillation of the front and rear vane members such that adjacent vane segments oscillate toward and away from one another simultaneously, thereby creating a bellowing effect which draws fluid into the chamber via the inlet and discharges fluid out of the chamber via the outlet. The invention further relates to an assembly for translating rotational motion of an input shaft to oscillatory motion of the vane members.

A radial piston machine includes a rotor within a housing that is rotatable about an axis, a shaft coupled to the rotor, a distributor which surrounds the shaft and cannot rotate with the rotor and that contacts the rotor in an axial direction, a plurality of brake discs including first brake discs and second brake discs arranged side-by-side along the axis, wherein the first brake discs are coupled to the housing for torque transmission, and the second brake discs are coupled to the shaft for torque transmission, and an actuator configured to releasably exert a brake force in the axial direction on the brake discs. The distributor is located axially between the rotor and the actuator, and the brake discs are located axially between the distributor and the actuator. When the brake force is exerted the brake force is supported by the distributor in the axial direction.

A magnetic driver generates a magnetic field that rotates about an axis and induces nutation in a disc with an array of magnets (wobble plate). The magnetic driver can be a drive disc with an array of magnets and rotated by a drive motor, or can be electromagnetic coils sequentially energized, to provide the rotating magnetic field. The wobble plate nutates about the axis of the rotating magnetic field but is constrained from rotating about the axis. The wobble plate can be enclosed in a pump housing where nutation of the wobble plate causes pumping of a fluid to occur, such as in an implanted Left Ventricular Assist Device (LVAD) or a Total Artificial Heart (TAH). Driven in reverse, an input pumping fluid may induce nutation of the wobble plate which in turn induces rotary motion of a drive disc that drives a generator or a motor/generator.

An active gas regenerative refrigerator includes a plurality of compressor-expander units, each having a hermetic cylinder with a drive piston configured to be driven reciprocally therein, and a quantity of working fluid in each end of the cylinder. A piston seal in a central portion of the cylinder prevents passage of the working fluid between ends of the cylinder. Movement of the piston to a first extreme results in radial compression of one of the quantities of working fluid in a cylindrical gap formed between one end of the piston and an inner surface of the cylinder, while the other quantity is expanded in the opposite end of the cylinder. The piston includes a plurality of magnets arranged in pairs, with magnets of each pair positioned with like-poles facing each other. A piston drive is configured to couple with transverse magnetic flux regions formed by the magnets.

A cylinder is installed within a case, and an output shaft and an arm that is integrated thereto and extends in a radial direction are installed within the cylinder. A piston extending in an arc slides and is displaced in a circumferential direction of the cylinder within the cylinder. One end portion of the piston is rotatably connected to the arm. The cylinder is internally provided with a first pressure chamber in which the arm is housed and a second pressure chamber in which the other end portion of the arm is slidably installed. A pressure medium is fed into one of the first and second pressure chambers and discharged from the other, and the output shaft pivots in a rotational direction.

An active gas regenerative refrigerator includes a plurality of compressor-expander units, each having a hermetic cylinder with a drive piston configured to be driven reciprocally therein, and a quantity of working fluid in each end of the cylinder. A piston seal in a central portion of the cylinder prevents passage of the working fluid between ends of the cylinder. Movement of the piston to a first extreme results in radial compression of one of the quantities of working fluid in a cylindrical gap formed between one end of the piston and an inner surface of the cylinder, while the other quantity is expanded in the opposite end of the cylinder. The piston includes a plurality of magnets arranged in pairs, with magnets of each pair positioned with like-poles facing each other. A piston drive is configured to couple with transverse magnetic flux regions formed by the magnets.

The invention relates to a piston machine which comprises: a housing with a chamber with has a substantially circle sector-shaped cross-section; a pivotal piston which is designed as a pivoting element, is arranged in the housing and comprises a first working surface, wherein the housing and the piston define at least one first variable working chamber; a drive or output which is connected to the piston; and an outlet which is arranged in the working chamber for discharging a working fluid. The housing has a cooling opening in at least one housing wall, said opening leading to the chamber at least for convectively cooling a piston side opposite the first working surface by means of a coolant.