Patent ID: 8025598

Claim:
A bicycle rear derailleur comprising: a base member; a movable member that supports a chain guide including a pulley that rotates around a pulley axis and a tension pulley, wherein the pulley has a pulley plane that bisects the pulley and is perpendicular to the pulley axis; and a linking member coupled between the base member and the movable member so that the chain guide moves laterally relative to the base member between a first lateral position and a second lateral position; wherein the base member has a frame mounting portion and a linking member coupling portion; wherein a linking member is coupled to the linking member coupling portion for rotation around a pivot axis; wherein a surface of the linking member coupling portion faces in at least one of a downward direction or a rearward direction; wherein a surface of the linking member coupling portion faces laterally; wherein a chain receiving space is defined by the intersection of (1) a projection of the laterally facing surface of the linking member coupling portion along the pivot axis with (2) a projection of the downward or rearward facing surface of the linking member coupling portion in the respective downward or rearward directions; wherein a phantom line corresponds to a position of a chain that engages the pulley and the tension pulley, wherein the phantom line extends from the pulley to the tension pulley such that one end of the phantom line terminates at the pulley and the other end of the phantom line terminates at the tension pulley; wherein the chain receiving space is dimensioned such that, while the chain guide is fixed in a same lateral position, the phantom line can move from outside the chain receiving space to inside the chain receiving space without intersecting the base member; and wherein the chain receiving space is dimensioned to receive at least a part of a chain that engages and extends from the pulley along the phantom line when the chain is operatively positioned on the derailleur.