A power train for a pedal vehicle includes a main output chainring and a secondary output chainring coupled to the crankset shaft by a first freewheel. The crankset shaft is coupled to the main output chainring via a deformable transmission element and an epicyclic gear.

A bicycle drive unit includes a housing, crankshaft and a propulsion assist motor. The housing is configured to be mounted on a frame of a bicycle. The housing includes a first portion and a second portion. The crankshaft is provided to the first portion of the housing. The propulsion assist motor is provided to the second portion of the housing and configured to assist propulsion of the bicycle. The propulsion assist motor includes a rotational axis extending in a direction intersecting a direction in which the crankshaft extends. The second portion has a maximum dimension of smaller than or equal to 75 mm in a direction orthogonal to the rotational axis of the propulsion assist motor.

A transmission for a bicycle includes an input shaft (1) which is rotationally fixable to a crankshaft (2), and an output shaft (3) which is rotationally fixable to an output gear. The transmission includes at least three planetary transmissions which are operatively connected to the input shaft and to the output shaft. A single one of the planetary transmissions includes a stepped planetary gear (4) with a first gear teeth section (5) having a first diameter and a second gear teeth section (6) having a second diameter.

A method for manufacturing a gear includes providing teeth which are shaped according to an epicyclic construction; wherein: locations on a respective tooth surface of each tooth are each determined by a radial distance from an axis as a function of a cycle angle; the radial distance is in turn determined by an equidistant to a gear trajectory; locations on the gear trajectory are respectively determined by the vector sum of a cycle vector and an epicycle vector; a tail of the cycle vector lies on the axis and a tail of the epicyclic vector lies in the tip of the cycle vector; an epicycle angle of the epicycle vector is n times as large as that cycle angle and a length of the cycle angle is greater than a length of the epicycle angle; and n is a number of the round engagement portions of the harmonic pin ring transmission which is at least three.

A power train of a pedal vehicle includes a crankset axle and a first output plate having a first axis of rotation. The first output plate is coupled with a transmission chain or belt so as to drive the rear wheel of the pedal vehicle. The coupling between the crankset axle and the transmission chain or belt extends through a planetary gear train which rotates about a second axis of rotation. The crankset axle is further coupled to the first output plate by a first free wheel (16) which is arranged to prevent the first output plate from rotating slower than the crankset axle when the crankset axle rotates in the normal pedalling direction.

A drive system, wherein: a drive shaft and an output shaft as well as a second motor, to-gether with the second rotor shaft thereof, are arranged coaxially in a first shafting; a multi-stage cross-drive steering transmission of the drive system, together with a sun gear, a ring gear and a planetary carrier, is designed solely as a three-shaft planetary gear stage, which is arranged in a second shafting parallel to the first shafting; and a first motor is arranged in a third shafting together with the first rotor shaft thereof, said third shafting being parallel to the first shafting and to the second shafting.

A multi-stage planetary transmission for a bicycle or a pedelec includes a transmission input shaft (1), a transmission output shaft (2), and at least three planetary gear sets (VRS, VR1, VR2, RS1, RS2, NRS, NR1, NR2). A first planetary gear set (RS1) and a second planetary gear set (RS2) are configured as a main gear set and at least one further planetary gear set (VRS, VR1, VR2, NRS, NR1, NR2) is configured as a front-mounted gear set and/or as a rear-mounted gear set. At least three free-wheel clutches (F1, F2, F3, F4) and at least three brakes (B1, B2, B3, B4) are provided for implementing at least eight gears (G1, G2, G3, G4, G5, G6, G7, G8, G9, G10, G11, G12, G13, G14, G15, G16). Moreover, the multi-stage transmission may be a bottom bracket transmission. In addition, a bicycle or pedelec with the multi-stage transmission is proposed.

A power train for a pedal vehicle includes a main output chainring and a secondary output chainring coupled to the crankset shaft by a first freewheel. The crankset shaft is coupled to the main output chainring via a deformable transmission element and an epicyclic gear.

A built-in motor for a bicycle and an electric powered bicycle are provided. The built-in motor includes: a motor shell, a motor inner stator fixed in the motor shell by means of an inner stator frame; a motor outer rotor is installed on the inner stator frame, the motor outer rotor and a motor body output shaft being connected into a whole; a first planetary gear mechanism arranged in the inner stator frame, and the first planetary gear mechanism being used for increasing input human force before outputting the same; a ring gear of the first planetary gear mechanism is connected with an elastic body, the elastic body being fixedly arranged in the inner stator frame; a torque sensor is arranged on the elastic body, the torque sensor being used for measuring the pedaling force provided by a rider to the bicycle.

Provided is a bicycle transmission using a variable speed motor and a planetary gear mechanism including: a first input rotary shaft (10) rotatably connected to a main power source (11); a second input rotary shaft (20) receiving a motor rotational power from a variable speed motor (21); a planetary gear mechanism (30) receiving first and second rotational power respectively from the first input rotary shaft (10) and the second input rotary shaft (20), wherein the planetary gear mechanism (30) includes a ring gear (33), a carrier (31), a plurality of planet gears (32), and a sun gear (34); an output shaft (40) receiving a third rotational power from the planetary gear mechanism (30); and a control unit (50) controlling the variable speed motor (21) and controlling a rotational direction and speed of the second input rotary shaft (20), wherein the first input rotary shaft (10) is arranged concentrically with the output shaft (40), the ring gear (33), the carrier (31), and the sun gear (34).