A linear energy harvesting device that includes a housing and a piston that moves at least partially through the housing when it is compressed or extended from a rest position. When the piston moves, hydraulic fluid is pressurized and drives a hydraulic motor. The hydraulic motor drives an electric generator that produces electricity. Both the motor and generator are central to the device housing. Exemplary configurations are disclosed such as monotube, twin-tube, tri-tube and rotary based designs that each incorporates an integrated energy harvesting apparatus. By varying the electrical characteristics on an internal generator, the kinematic characteristics of the energy harvesting apparatus can be dynamically altered. In another mode, the apparatus can be used as an actuator to create linear movement. Applications include vehicle suspension systems (to act as the primary damper component), railcar bogie dampers, or industrial applications such as machinery dampers and wave energy harvesters, and electro-hydraulic actuators.

This internal gear pump accommodates: a ring-shaped internally toothed gear provided with internal teeth, and an externally toothed gear provided with external teeth which internally mesh with the internal teeth of the internally toothed gear, said externally toothed gear being eccentrically disposed inside the internally toothed gear. The number of internal teeth is one greater than the number of external teeth. In any one of the external teeth and the internal teeth, a tooth tip section and a meshing section are formed by a curve having one continuous curvature. The curve is formed by an equation with which the maximum curvature is at the apex of the tooth tip, and the curvature gradually reduces towards the tooth bottom section.

A linear energy harvesting device that includes a housing and a piston that moves at least partially through the housing when it is compressed or extended from a rest position. When the piston moves, hydraulic fluid is pressurized and drives a hydraulic motor. The hydraulic motor drives an electric generator that produces electricity. Both the motor and generator are central to the device housing. Exemplary configurations are disclosed such as monotube, twin-tube, tri-tube and rotary based designs that each incorporates an integrated energy harvesting apparatus. By varying the electrical characteristics on an internal generator, the kinematic characteristics of the energy harvesting apparatus can be dynamically altered. In another mode, the apparatus can be used as an actuator to create linear movement. Applications include vehicle suspension systems (to act as the primary damper component), railcar bogie dampers, or industrial applications such as machinery dampers and wave energy harvesters, and electro-hydraulic actuators.

A gas-cycle system operable using a Bell-Coleman cycle, the gas-cycle system comprising an expander (23) and a compressor (27) incorporated in a flow path (13). The expander (23) and compressor (27) are integrated in a rotary machine (41), and each comprises a rotor assembly (70) configured to define one or more zones (80) each of which changes continuously in volume during a rotation cycle of the rotor assembly. The expander (23) and compressor (27) are drivingly interconnected whereby rotational drive applied to one is transmitted directly to the other. Each rotor assembly (70) comprises an inner rotor (73) and an outer rotor (75) adapted to rotate about parallel axes at different rotational speeds. The inner rotors (73) are each drivingly connected to a common shaft for rotation therewith. The two outer rotors (75) are coupled together such that rotational drive applied to one is transmitted directly to the other. An air-cycle system and an air conditioning system (10) based on the gas-cycle system are also disclosed.

In a rotor in rotor configuration, a pump has inward projections on an outer rotor and outward projections on an inner rotor. The outer rotor is driven and the projections mesh to create variable volume chambers. The outer rotor may be driven in both directions. In each direction, the driving part (first inward projection) of the outer rotor contacts a sealing surface on one side of an outward projection of the inner rotor, while a gap is left between a sealing surface of the other side of the outward projection and a second inward projection. The gap may have uniform width along its length in the radial direction, while in a direction parallel to the rotor axis it may be discontinuous or have variable size to create flow paths for gases.

A linear energy harvesting device that includes a housing and a piston that moves at least partially through the housing when it is compressed or extended from a rest position. When the piston moves, hydraulic fluid is pressurized and drives a hydraulic motor. The hydraulic motor drives an electric generator that produces electricity. Both the motor and generator are central to the device housing. Exemplary configurations are disclosed such as monotube, twin-tube, tri-tube and rotary based designs that each incorporates an integrated energy harvesting apparatus. By varying the electrical characteristics on an internal generator, the kinematic characteristics of the energy harvesting apparatus can be dynamically altered. In another mode, the apparatus can be used as an actuator to create linear movement. Applications include vehicle suspension systems (to act as the primary damper component), railcar bogie dampers, or industrial applications such as machinery dampers and wave energy harvesters, and electro-hydraulic actuators.

A piston is arranged to move in a cylinder to define a variable volume chamber, and can expand in two directions under the influence of pressure in the variable volume chamber to provide sealing against the cylinder. The piston can comprise a primary foot and a secondary foot arranged to move relative to each other in a first direction. The primary foot and the secondary foot can each comprise plural segments arranged to move relative to each other in a second direction. The piston may be suitable for use in an inner rotor, where it forms the end of a projection of the inner rotor and fully exits and reenters the cylinders.

A linear energy harvesting device that includes a housing and a piston that moves at least partially through the housing when it is compressed or extended from a rest position. When the piston moves, hydraulic fluid is pressurized and drives a hydraulic motor. The hydraulic motor drives an electric generator that produces electricity. Both the motor and generator are central to the device housing. Exemplary configurations are disclosed such as monotube, twin-tube, tri-tube and rotary based designs that each incorporates an integrated energy harvesting apparatus. By varying the electrical characteristics on an internal generator, the kinematic characteristics of the energy harvesting apparatus can be dynamically altered. In another mode, the apparatus can be used as an actuator to create linear movement. Applications include vehicle suspension systems (to act as the primary damper component), railcar bogie dampers, or industrial applications such as machinery dampers and wave energy harvesters, and electro-hydraulic actuators.

In a rotor in rotor configuration, a pump has inward projections on an outer rotor and outward projections on an inner rotor. The outer rotor is driven and the projections mesh to create variable volume chambers. The outer rotor may be driven in both directions. In each direction, the driving part (first inward projection) of the outer rotor contacts a sealing surface on one side of an outward projection of the inner rotor, while a gap is left between a sealing surface of the other side of the outward projection and a second inward projection. The gap may have uniform width along its length in the radial direction, while in a direction parallel to the rotor axis it may be discontinuous or have variable size to create flow paths for gases.

A gas-cycle system operable using a Bell-Coleman cycle, the gas-cycle system comprising an expander (23) and a compressor (27) incorporated in a flow path (13). The expander (23) and compressor (27) are integrated in a rotary machine (41), and each comprises a rotor assembly (70) configured to define one or more zones (80) each of which changes continuously in volume during a rotation cycle of the rotor assembly. The expander (23) and compressor (27) are drivingly interconnected whereby rotational drive applied to one is transmitted directly to the other. Each rotor assembly (70) comprises an inner rotor (73) and an outer rotor (75) adapted to rotate about parallel axes at different rotational speeds. The inner rotors (73) are each drivingly connected to a common shaft for rotation therewith. The two outer rotors (75) are coupled together such that rotational drive applied to one is transmitted directly to the other. An air-cycle system and an air conditioning system (10) based on the gas-cycle system are also disclosed.