PURPOSE: To prevent generation of noise during operation and to increase the riding comfortableness by increasing machining preciseness as well as reducing the production cost of the differential device and by setting a ratio of a man power to an auxiliary power near 1 to 1 without impairing power transmission efficiency, also by making accurate the input timing of the man power and auxiliary power.
CONSTITUTION: An auxiliary power generating means (electric motor 53) is arranged coaxially with a differential device 54 which outputs a combined power of the power from a crank shaft 33 and an auxiliary power to drive wheel side, and the auxiliary power is so constituted as to input into the differential device 54 through gears (66, 79, 90, and 91). Also the input parts of the differential device 54 are a man power input gear 69 provided rotatably with the crank shaft 33 and an auxiliary power input gear 72 provided rotatably. Then a first planetary gear 76 meshed with the man power input gear 69 and a second planetary gear 77 meshed with the auxiliary power input gear 72 are held rotatably on a differential carrier 74 on which an output part is provided rotatably around the crank shaft 33 under the condition that they are meshed with each other.
TSUTSUMIGOSHI SHINOBU
NAGAI HISAO
MATSUURA TADASHI
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