Abstract: A harmonic speed reducer is provided. The harmonic speed reducer includes a wave generator, a flexible gear, a first rigid gear, and a second rigid gear. The wave generator can be driven to rotate relative to a central axis. The flexible gear has a plurality of first outer gear structures, a division groove, and a plurality of second outer gear structures. The first rigid gear has a plurality of first inner gear structures configured to be engaged with the first outer gear structures. The second rigid gear has a plurality of second inner gear structures configured to be engaged with the second outer gear structures. A first intersection line is defined between each of the first inner gear structures and a sectional surface. An angle between the first intersection line and a first horizontal line is within a range from 0.1 degrees to 5 degrees.

Abstract: A harmonic speed reducer is provided. The harmonic speed reducer includes a wave generator, a flexible gear, a first rigid gear, and a second rigid gear. The wave generator can be driven to rotate relative to a central axis. The flexible gear has a plurality of first outer gear structures, a division groove, and a plurality of second outer gear structures. The first rigid gear has a plurality of first inner gear structures configured to be engaged with the first outer gear structures. The second rigid gear has a plurality of second inner gear structures configured to be engaged with the second outer gear structures. A first intersection line is defined between each of the first inner gear structures and a sectional surface. An angle between the first intersection line and a first horizontal line is within a range from 0.1 degrees to 5 degrees.

Abstract: A harmonic deceleration module, a dynamic power device, an automatic mobile vehicle, a transfer apparatus, a dynamic power supply system, and an electric bicycle are provided. The harmonic deceleration module includes a connecting member, a flexible bearing, a first frame, a first circular spline, a second frame, and a second circular spline. When the connecting member is driven, the connecting member rotates around a central axis. The connecting member has a cam part, and the cam part and the flexible bearing jointly form a wave generator. The wave generator is configured to be driven by the connecting member to drive a flexspline to continually and flexibly deform, and the flexspline drives the second circular spline and the second frame connected to the second circular spline to rotate. The second frame has a hollow channel penetrating through the second frame along the central axis.

Abstract: An electric motor includes a casing, a stator, a rotor and a first coolant guiding structure. The stator is stored in a storage space of the casing. The stator includes a stator yoke and winding sets. The stator yoke has first side, second side, annular external surface and guiding channel. The first coolant guiding structure is disposed close to the winding sets and an inlet channel. The first coolant guiding structure has first radially guiding channel and first axially guiding channel. Two ends of the first radially guiding channel respectively have a first radial inlet and a first radial outlet. The first radial inlet is connected to the first axially guiding channel in order to receive coolant from the first axially guiding channel. The first radial outlet is aligned with at least one of the winding sets in order to supply coolant to the winding sets.