IPC Definitions - January 01, 2012
B62M 9/124 - Definition
This group covers:
Rear derailleurs comprising all or most of the following features: a fixed member connected to the bicycle frame, a base member, a linkage mechanism, a movable member and chain guides, cable receiving and connecting portions, springs or the like devices. The linkage mechanism insures proper lateral shift movement of the chain over the different rear sprockets by acting on the chain guide. The mechanism can comprise articulated linkages, plates, cams or telescopic shafts.