Modular motorized electric wheel hub assembly for bicycles and the like

A motorized hub assembly comprising

• a sealed motor section having stationary first and second end walls and a stationary side wall extending between the end walls, stator windings fixed to and in intimate thermal contact with said side and end walls,
• a rotor rotatably mounted within the stator windings, a first shaft extending from the first end wall and a second shaft connected to said rotor and having an end extending through the second end wall, said second shaft being coaxial to but spaced axially from the first shaft, and
• a gear reduction section adjacent to the second end wall, said gear reduction section including a pinion at the end of the second shaft, a gear support connected to the second end wall, a plurality of nonorbiting planet gears rotatably mounted between the second end wall and the gear support in meshing engagement with the pinion, a hub having an interior surface closely surrounding the motor section side and first end walls and the planet gears, means including a third shaft for rotatably coupling the hub to the first shaft and the gear support, and a ring gear formed at the interior of the hub in meshing engagement with the planet gears so that when said windings are energized, the heat produced thereby is conducted by said side and first end walls to said hub and thence to the outside while the hub rotates relative to the first shaft a at speed less than that of the second shaft.