A drive arrangement for a bicycle or pedelec includes a manual drive shaft (1) in a housing (2). A rotor (3) of a first electric drive (EM 1) is arranged axially parallel to the manual drive shaft (1), and a rotor (4) of a second electric drive (EM2) is arranged coaxially to the manual drive shaft (1). The rotor (3) of the first electric drive (EM 1) is coupled to a first planetary gear set (PS 1) as a superposition gearbox via a first fixed ratio. The rotor (4) of the second electric drive (EM 2) is coupled to the manual drive shaft (1) via a second fixed ratio. The manual drive shaft (1) is coupled to the first planetary gear set (PS 1) as the superposition gearbox, and the first planetary gear set (PS 1), as the superposition gearbox, is coupled to an output (5).

A transmission for a bicycle includes at least four shift elements, an input shaft (1), a first planetary gear set (PS1) which is operatively connected to the input shaft (1), a second planetary gear set (PS2) which is operatively connectable to the input shaft (1), and an output shaft (2). The input shaft (1) is rotationally fixed to a ring gear of the first planetary gear set (PS1), and the output shaft (2) is rotationally fixed to a carrier of the first planetary gear set (PS1).

A transmission for a bicycle includes at least four shift elements, an input shaft (1), a first planetary gear set (PS1) which is operatively connected to the input shaft (1), a second planetary gear set (PS2) which is operatively connectable to the input shaft (1), and an output shaft (2). The input shaft (1) is rotationally fixed to a ring gear of the first planetary gear set (PS1), and the output shaft (2) is rotationally fixed to a carrier of the first planetary gear set (PS1).

A bicycle gear hub includes an axle, planetary gear modules, one-way clutches and a shift mechanism. The planetary gear modules are connected in series at the axle. The shift mechanism includes a shift actuator and control pawls movably disposed at different positions of the axle. The shift actuator includes recess portions to control opening and closing of a control protrusion of one control pawl, and further to control a sun gear of the corresponding planetary gear module to the axle. When a high gear is shifted to a low gear, a rotational direction of the shift actuator is identical to a rotational direction for closing the control pawl.

A bicycle gear hub includes an axle, planetary gear modules, one-way clutches and a shift mechanism. The planetary gear modules are connected in series at the axle. The shift mechanism includes a shift actuator and control pawls movably disposed at different positions of the axle. The shift actuator includes recess portions to control opening and closing of a control protrusion of one control pawl, and further to control a sun gear of the corresponding planetary gear module to the axle. When a high gear is shifted to a low gear, a rotational direction of the shift actuator is identical to a rotational direction for closing the control pawl.

A transmission for a bicycle includes at least four shift elements, one input shaft (1), a first planetary gear set (PS1) which is operatively connected to the input shaft (1), and a second planetary gear set (PS2). A carrier of the first planetary gear set is rotationally fixed to a carrier of the second planetary gear set (PS2).

A transmission for a bicycle includes at least four shift elements, one input shaft (1), a first planetary gear set (PS1) which is operatively connected to the input shaft (1), and a second planetary gear set (PS2). A carrier of the first planetary gear set is rotationally fixed to a carrier of the second planetary gear set (PS2).

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.

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.

A bicycle gear change mechanism includes a first gear including first teeth and a second gear including second teeth. Each of the first teeth includes a first surface and a second surface. The first surface defines a first pressure angle. The second surface defines a second pressure angle. The first pressure angle differs from the second pressure angle. Each of the second teeth includes a third surface and a fourth surface. The third surface defines a third pressure angle. The fourth surface defines a fourth pressure angle. The third pressure angle differs from the fourth pressure angle. The second gear engages the first gear.