Patent ID: 9108312
Filing Date: 2015-08-18
Classification: B25F

Abstract:
1. A multi-stage planetary transmission powered by an electric motor having an output pinion, the transmission comprising: a transmission housing; a first planetary stage at least partially positioned in the transmission housing and including a second planetary stage positioned downstream of the first planetary stage to receive torque from the first planetary stage; a third planetary stage positioned downstream of the second planetary stage to receive torque from the second planetary stage, the second and third planetary stages sharing a one-piece common ring gear; and a shift mechanism operable to move the first stage ring gear between a first position, in which the first stage ring gear is rotatably fixed relative to the transmission housing for enabling the first planetary stage, and a second position, in which the first stage ring gear is coupled for co-rotation with the first stage carrier about a central axis for disabling the first planetary stage, wherein an axial position of the common ring gear along the central axis remains unchanged when the first stage ring gear is moved between the first position and the second position.