Patent attributes
A driving device of the invention has a clutch 40 and a continuously variable transmission 50. The clutch 40 couples and decouples a rotating shaft 24 or an output shaft of a motor 30 with and from a driveshaft 22. The continuously variable transmission 50 has an input shaft connected to the rotating shaft 24 and an output shaft connected to the driveshaft 22 via a gear mechanism 52. A spring 36 is attached to a rotor 31 of the motor 30 to apply a pressing force and cause the clutch 40 to couple the rotating shaft 24 with the driveshaft 22 in response to a relatively small output torque of the motor 30. With an increase in output torque of the motor 30, a thrust force produced in the motor 30 moves the rotating shaft 24 against the pressing force of the spring 36 to cause the clutch 40 to decouple the rotating shaft 24 from the driveshaft 22. The output torque of the motor 30 is then transmitted to the driveshaft 22 with a gear change of the continuously variable transmission 50.
