Patent attributes
An electric derailleur has a motor unit having a derailleur motor with an output shaft, a position control mechanism and a controller. The output shaft is rotated through a moveable range including a first derailleur shift position and a second derailleur shift position. The position control mechanism is configured and arranged to provide a position signal indicative of an angular position of the output shaft. The controller detects a predetermined lockup position of the derailleur motor occurring at one of the first and second derailleur shift positions. The controller also sets a predetermined stop position for the derailleur motor that is calculated distance prior to the lockup position based on the position signal of the position control mechanism. Thus, the derailleur motor can be calibrated such that a new stop position is set that prevents an overcurrent from occurring in the motor.
