Abstract: An exercise device is provided using, for example, handles, connected to cords that increase in tension as the handles are pulled. The tension may be provided using elasticity of the cords or by an actuator, for example powered by an electric motor. Pulleys allow adequate extension while remaining compact enough to fit in a standard height room and allowing accessibility to components. Upper and forward pulleys may be used. The upper pulleys may be displaced from potential obstacles, including the forward pulleys.

Abstract: An internal gear pump or motor includes inner and outer rotors that mesh together. An internal electric motor or generator may include a stator supported by a support element that passes through bearings of the outer rotor and the inner rotor may act as a rotor of the electric motor or generator. With or without the stator, the support element may support bearings of the inner rotor. Fluids may be supplied via the support element for cooling, lubrication or to flush a working fluid out of portions of the pump or motor, such as bearings. Flushing may also occur via channels in the housing. Axial faces of one of a pair of adjacent elements may include portions for improved axial sealing and wearing in of the other of the pair. Fluid may enter and exit chambers between the inner and outer rotors by radial ports.

Abstract: An energy return device for footwear has a flattenable conical disk with a ring spring arranged around the base of the conical disk. A rigid upper heel-receiving plate is connected to the apex of the flattenable conical disk. The heel-receiving plate may be rigidly or semi-rigidly attached to the apex of the conical disk to stabilize an angle of the heel-receiving plate. There may be a conical damping disk between a lower surface of the heel-receiving plate and an upper surface of the conical disk. There may be protrusions on the bottom of the heel-receiving plate which interact with pockets in the upper surface of the conical disk, for example distorting the conical damping disk. There may be viscoelastic inserts in the pockets, for example providing damping in place of or in addition to the damping disk.

Abstract: An internal gear pump or motor includes inner and outer rotors that mesh together. An internal electric motor or generator may include a stator supported by a support element that passes through bearings of the outer rotor and the inner rotor may act as a rotor of the electric motor or generator. With or without the stator, the support element may support bearings of the inner rotor. The support element may be, for example, an eccentric shaft. Fluids may be supplied via the support element, if present, for cooling, lubrication or to flush a working fluid out of portions of the pump or motor, such as bearings. Flushing may also occur via channels in the housing with or without the presence of the support element. Axial faces of one of a pair of adjacent elements, for example the inner rotor and the outer rotor, may include portions for improved axial sealing and wearing in of the other of the pair. Fluid may enter and exit chambers between the inner and outer rotors by radial ports.

Abstract: A positive displacement gear pump or gear hydraulic motor having at least a first rotor with first rotor teeth and a second rotor with second rotor teeth, the first rotor teeth meshing with the second rotor teeth. First rotor chambers are defined between first rotor teeth and second rotor chambers are defined between the second rotor teeth. As the rotors mesh, the first rotor chambers, second rotor chambers or both become enclosed or substantially enclosed to form what are referred to here as secondary chambers. Pressure variations in a secondary chamber are relieved by internal flow channels in the first rotor, second rotor or both, creating a fluid connection between the first rotor chambers and the second rotor chambers. The first rotor may be an internal gear rotor or both rotors may be external gear rotors.

Abstract: An energy transfer machine includes a piston and cylinder. The piston can have a rocking motion as it enters and exits the cylinder, for example due to one being on a rotor and the other on a stator. The piston and cylinder form a primary chamber, and as they move relative to each other can form a seal separating the primary chamber into first and second sub-chambers which then unseals before the piston exits the cylinder. The first sub-chamber may reach a maximum geometric compression ratio, for example for the purpose of compression ignition, before the unsealing of the sub-chambers.

Abstract: An exercise device is provided using, for example, handles, connected to cords that increase in tension as the handles are pulled. The tension may be provided using elasticity of the cords or by an actuator, for example powered by an electric motor. Pulleys allow adequate extension while remaining compact enough to fit in a standard height room and allowing accessibility to components. Upper and forward pulleys may be used. The upper pulleys may be displaced from potential obstacles, including the forward pulleys.

Abstract: An internal gear pump or motor includes inner and outer rotors that mesh together. An internal electric motor or generator may include a stator supported by a support element that passes through bearings of the outer rotor and the inner rotor may act as a rotor of the electric motor or generator. With or without the stator, the support element may support bearings of the inner rotor. The support element may be, for example, an eccentric shaft. Fluids may be supplied via the support element, if present, for cooling, lubrication or to flush a working fluid out of portions of the pump or motor, such as bearings. Flushing may also occur via channels in the housing with or without the presence of the support element. Axial faces of one of a pair of adjacent elements, for example the inner rotor and the outer rotor, may include portions for improved axial sealing and wearing in of the other of the pair. Fluid may enter and exit chambers between the inner and outer rotors by radial ports.

Abstract: An energy transfer machine includes a piston and cylinder. The piston can have a rocking motion as it enters and exits the cylinder, for example due to one being on a rotor and the other on a stator. The piston and cylinder form a primary chamber, and as they move relative to each other can form a seal separating the primary chamber into first and second sub-chambers which then unseals before the piston exits the cylinder. The first sub-chamber may reach a maximum geometric compression ratio, for example for the purpose of compression ignition, before the unsealing of the sub-chambers.

Abstract: A positive displacement gear pump or gear hydraulic motor having at least a first rotor with first rotor teeth and a second rotor with second rotor teeth, the first rotor teeth meshing with the second rotor teeth. First rotor chambers are defined between first rotor teeth and second rotor chambers are defined between the second rotor teeth. As the rotors mesh, the first rotor chambers, second rotor chambers or both become enclosed or substantially enclosed to form what are referred to here as secondary chambers. Pressure variations in a secondary chamber are relieved by internal flow channels in the first rotor, second rotor or both, creating a fluid connection between the first rotor chambers and the second rotor chambers. The first rotor may be an internal gear rotor or both rotors may be external gear rotors.

Abstract: An energy transfer machine includes a piston and cylinder. The piston can have a rocking motion as it enters and exits the cylinder, for example due to one being on a rotor and the other on a stator. The piston and cylinder form a primary chamber, and as they move relative to each other can form a seal separating the primary chamber into first and second sub-chambers which then unseals before the piston exits the cylinder. The first sub-chamber may reach a maximum geometric compression ratio, for example for the purpose of compression ignition, before the unsealing of the sub-chambers.

Abstract: An internal gear pump or motor includes inner and outer rotors that mesh together. An internal electric motor or generator may include a stator supported by a support element that passes through bearings of the outer rotor and the inner rotor may act as a rotor of the electric motor or generator. With or without the stator, the support element may support bearings of the inner rotor. The support element may be, for example, an eccentric shaft. Fluids may be supplied via the support element, if present, for cooling, lubrication or to flush a working fluid out of portions of the pump or motor, such as bearings. Flushing may also occur via channels in the housing with or without the presence of the support element. Axial faces of one of a pair of adjacent elements, for example the inner rotor and the outer rotor, may include portions for improved axial sealing and wearing in of the other of the pair.

Abstract: An energy transfer machine includes a piston and cylinder. The piston can have a rocking motion as it enters and exits the cylinder, for example due to one being on a rotor and the other on a stator. The piston and cylinder form a primary chamber, and as they move relative to each other can form a seal separating the primary chamber into first and second sub-chambers which then unseals before the piston exits the cylinder. The first sub-chamber may reach a maximum geometric compression ratio, for example for the purpose of compression ignition, before the unsealing of the sub-chambers.

Abstract: A torque transfer device has plural planets arranged for planetary rotation about one or more sun gears and within one or more ring gears. Each planet includes at least one planetary gear set comprising plural planetary gears connected to rotate together, but having a different diameter to form a differential gear system. To improve load sharing, the plural planetary gears of each planetary gear set may have a different helical angle, the plural planetary gear sets being axially movable with respect to one another. Alternatively or in addition, the planetary gears may be made flexible with respect to radial forces.

Abstract: A displacement device including an inner rotor and an outer rotor with meshing projections. Points on each rotor trace a hypotrochoidal path relative to the other. The tips of the outer rotor projections may contact the inner rotor at Top Dead Center (TDC) and Bottom Dead Center (BDC) to form higher and lower pressure regions. Various elements may shape other elements to form seals.

Abstract: A displacement device including an inner rotor and an outer rotor with meshing projections. Points on each rotor trace a hypotrochoidal path relative to the other. The tips of the outer rotor projections may contact the inner rotor at Top Dead Center (TDC) and Bottom Dead Center (BDC) to form higher and lower pressure regions. Various elements may shape other elements to form seals.

Abstract: A planetary gearbox with two rows of planets, at least some of the planets including magnets. The planets are driven by a stator to drive the gearbox as a motor. The planets may be geared with axial portions with different helix angle to position the gears and avoid the need for a planet carrier or bearings. Gears with small heights and/or high pressure angles may be used to avoiding or reduce negative effects of conventional gearing.

Abstract: A torque transfer device has a ring gear and inner and outer planet gear sets, which may not be orbiting but rotating in fixed positions relative to a housing. One of the gear sets may comprise compound gears. There may also be a sun gear connected to a planet gear set. The sun gear may be an input and the ring gear an output for a reducing gear system to act as a torque amplifier. The gears may be tapered and there may also be an axial force applied to one of the gear sets to tighten the meshing between the tapered gears. One of the gear sets, for example a gear set to which an axial force is applied, may be floating.

Abstract: A planetary gearbox with two rows of planets between an inner race and a coaxial outer race. An input gear may also mesh with the inner planets or the outer planets. To avoid unmeshing of the gears due to twisting from the applied torque, a camming effect may be used in which applied torque generates a radial preload. The gears that mesh with the input gear may do so at portions of the gears that also mesh with a corresponding one of the inner or outer race. The planets may be geared with axial portions with different helix angle. The inner race or outer race may be formed of two components geared with different helix angle to mesh with the different axial portions of the planets. By using these different components, assembly is eased as the components can be slid onto the planets axially.