Patent ID: 8137230

Claim:
A reduction gear comprising: a first planetary gear set reducing an output rotation speed of a power source, the first planetary gear set possessing a first ring gear, a counter gear set reducing an output rotation speed of the first planetary gear set, and a second planetary gear set reducing an output rotation speed of the counter gear set, the second planetary gear set possessing a second ring gear, wherein an output shaft and an input shaft coaxially disposed in the first planetary gear set are arranged in parallel with an output shaft and an input shaft coaxially disposed in the second planetary gear set, an input shaft of the counter gear set is common to the output shaft of the first planetary gear set, an output shaft of the counter gear set is common to the input shaft of the second planetary gear set, an output gear of the counter gear set and a wheel shaft are coaxial, and the first ring gear and the second ring gear are rotationally fixed relative to a case.