Patent ID: 7442136
Filing Date: 2008-10-28
Classification: B62M,Y10T

Abstract:
1. A motorized bicycle front derailleur assembly comprising: a motor unit configured and arranged to rotate an output shaft in a first rotational direction and a second rotational direction that is opposite the first rotational direction; a front derailleur including a fixing body configured to be mounted to a bicycle frame, an inner link pivotally coupled to the fixing body at a first pivot point, an outer link pivotally coupled to the fixing body at a second pivot point and a chain guide pivotally coupled to the inner and outer links to move between an inner shift position and an outer shift position, the first pivot point being located laterally closer to a center plane of the bicycle frame than the second pivot point; and a motor linkage directly coupled to the output shaft of the motor unit and directly coupled to the inner link of the front derailleur to move the chain guide from the inner shift position to the outer shift position upon rotation of the output shaft in the first rotational direction and to move the chain guide from the outer shift position to the inner shift position upon rotation of the output shaft in the second rotational direction, with the outer link of the front derailleur being separate from the motor linkage, the motor linkage includes a drive link having a first drive link end operatively coupled to the output shaft of the motor unit and a second drive link end operatively coupled to the inner link of the front derailleur to move the chain guide from the inner shift position to the outer shift position when the first drive link end is pulled in a direction away from the second drive link end, the output shaft includes an eccentric drive pin that is offset from a rotational axis of the output shaft, the first drive link end of the drive link is pivotally coupled to the eccentric drive pin such that the eccentric drive pin is configured to selectively pull the first drive link end in the direction away from the second drive link end to shift the chain guide from the inner shift position to the outer shift position and to selectively push the first drive link end in a direction toward the second drive link end to shift the chain guide from the outer shift position to the inner shift position, the motor linkage includes a jamming protection connection arranged between the drive link and the inner link such that the drive link is permitted to move from an outer shift orientation to an inner shift orientation even if the chain guide is prohibited from moving to the inner shift position from the outer shift position, the jamming protection connection includes a biasing element configured and arranged to apply an urging force that normally maintains the jamming protection connection in a normally rigid state, the jamming protection connection includes a saver link having a first saver link end pivotally coupled to the second drive link end and a second saver link end pivotally coupled to the inner link, and the biasing element is arranged between the saver link and the inner link to apply the urging force that normally maintains the saver link and the inner link in the normally rigid state.