This patent discloses compact size drive mechanism for bikes and reverse trikes. Drive mechanism comprises a pair of drive assemblies mounted on the ends of the hub of the wheel. Each drive assembly comprises a special type of planetary gearbox in which plurality of planetary gears and a gear ring are arranged in such a way that gear ring can be rotated via pedal which in turn rotates planetary gears. Hub of the wheel at each end is coaxially connected to a planetary gear of the gearbox via one way ratchet ball bearing. Planetary gear on rotation rotates the wheel. Larger radius of the gear ring than planetary gears accounts for gear ratio. Drive mechanism doesn't come in contact with clothing of the rider. Specially designed rear wheel support system secures the wheel to the frame, provides reinforcement to drive assembly position and is aligned to promote forward motion.

A system for assisting a user in moving a device relative to a structure comprises a magnetorheological (MR) fluid actuator unit including at least one torque source and at least one MR fluid clutch apparatus having an input coupled to the at least one torque source to receive torque from the at least one torque source, the MR fluid clutch apparatus controllable to transmit a variable amount of assistance force via an output thereof. An interface is configured for coupling the output of the at least one MR fluid clutch apparatus to the device or surrounding structure. At least one sensor provides information about a movement of the device. A processor unit for controlling the at least one MR fluid clutch apparatus in exerting the variable amount of assistance force as a function of said information, wherein the system is configured for one of the MR fluid actuator unit and the interface to be coupled to the structure, and for the other of the MR fluid actuator unit and the interface to be coupled to the device for the assistance force from the MR fluid actuator unit to assist in moving the device.

Aspects of the present disclosure relate to a gymnastic apparatus and method for cycling simulation having a transmission portion driven by pedals, through which a user may perform cycling training. The transmission portion may comprise a flywheel and a braking portion, which may apply a braking force to the flywheel. The apparatus may further comprise a control logic unit, through which training parameters may be set, and a sensor coupled to the control logic unit. The sensor may detect a signal relating to the torque acting on the flywheel and thereby send a signal to the control logic unit; the control logic unit may be configured to adjust the braking force of the braking portion applied to the flywheel, thereby adjusting the resistance to the pedals as a function of parameters set, as appropriate, and communicate information and adjust such changes via a feedback signal from the sensor.

A system for assisting a user in moving a device relative to a structure comprises a magnetorheological (MR) fluid actuator unit including at least one torque source and at least one MR fluid clutch apparatus having an input coupled to the at least one torque source to receive torque from the at least one torque source, the MR fluid clutch apparatus controllable to transmit a variable amount of assistance force via an output thereof. An interface is configured for coupling the output of the at least one MR fluid clutch apparatus to the device or surrounding structure. At least one sensor provides information about a movement of the device. A processor unit for controlling the at least one MR fluid clutch apparatus in exerting the variable amount of assistance force as a function of said information, wherein the system is configured for one of the MR fluid actuator unit and the interface to be coupled to the structure, and for the other of the MR fluid actuator unit and the interface to be coupled to the device for the assistance force from the MR fluid actuator unit to assist in moving the device.

A bicycle includes an electrical auxiliary drive, including an electric motor, a battery for storing electrical energy, which battery is connected to the electric motor, a crank mechanism having pedal cranks, which are mounted on a pedal crankshaft disposed about a crank axis, so as to be able to rotate, and a planetary gear for driving the bicycle both by the electric motor and by the muscle power of a driver, the planetary gear and the electric motor being disposed about the pedal crankshaft of the crank mechanism.

A centerless wheel assembly may include a centerless rim configured to rotate about a point. The centerless wheel assembly may also include a centerless flywheel that may be configured to indirectly couple with the centerless rim and to rotate about a point. The centerless wheel assembly may additionally include a device for rotating the centerless rim in a first direction and in a second direction. The centerless wheel assembly may also include a one-way bearing that may be disposed between the centerless rim and the centerless flywheel. The one-way bearing may be positioned such that as the centerless rim may rotate in the first direction, the centerless flywheel may be caused to rotate in the first direction and as the centerless rim may rotate in the second direction, the centerless flywheel may not be caused to rotate.

Traction planets and traction rings can be operationally coupled to a planetary gearset to provide a continuously variable transmission (CVT). The CVT can be used in a bicycle. In one embodiment, the CVT is mounted on the frame of the bicycle at a location forward of the rear wheel hub of the bicycle. In one embodiment, the CVT is mounted on and supported by members of the bicycle frame such that the CVT is coaxial with the crankshaft of the bicycle. The crankshaft is configured to drive elements of the planetary gearset, which are configured to operationally drive the traction rings and the traction planets. Inventive component and subassemblies for such a CVT are disclosed. A shifting mechanism includes a plurality of pivot arms arranged to pivot about the centers of the traction planets as a shift pin hub moves axially.

A bicycle crank transmission apparatus includes: a hollow shaft member; a base plate coupled to the shaft member on one side and installed securely on a bottom bracket featuring a spindle on the other side; a chainring housing coupled to the shaft member in a way that allows its rotation and having a ring gear installed securely inside; a reduction gear unit arranged in the middle of the ring gear; a directly-coupled ratchet unit installed on the ring gear; a crank cover where a coupling shaft coupled to the spindle is perpendicularly provided in the center and where clutch ratchet teeth, which are engaged with the directly-coupled ratchet unit, and directly-coupled ratchet teeth are vertically stacked on the internal wall surface; and a sun gear installed on the coupling shaft in such a way that it only rotates in clockwise direction and partially engaged with the reduction gear unit.

A powertrain for a pedal vehicle includes a crank axle and an output sprocket rotating around a first rotation axis. The coupling between the crank axle and the output sprocket goes through an epicyclic gear system that includes a ring gear, a planet carrier, and a sun gear (13) which rotate around a second rotation axis that is spatially offset from the first rotation axis.

A gear (10) for a bicycle transmission (20) is described, having an external contour (11) with teeth (12a, 12b) formed thereon, wherein the external contour (11) is defined by a maximum pitch diameter (.sub.max) and a minimum pitch diameter (.sub.min), does not have any axes of symmetry and is formed exclusively with point symmetry with respect to its centre of symmetry (M). The invention was therefore based on the problem of developing a gear (10) which improves the pedaling feel of a bicycle transmission (20). The problem is solved in that the external contour (11) exhibits a change in its curvature at every point.