Patent ID: 8303443

Claim:
A front derailleur for shifting a bicycle chain, comprising: an attachment mechanism configured for affixing the front derailleur to a bicycle frame member; a chain guide configured for surrounding and contacting a bicycle chain during shifting; and a movement mechanism supported by the attachment mechanism and supporting the chain guide, the movement mechanism configured for selectively positioning the chain guide above and behind selected chain rings, thereby causing the bicycle chain to shift gears, the movement mechanism further comprising seven pivot points and six links, the six links including: a first link formed between first and second pivot points, located adjacent to the chain guide; a second link beginning at the first pivot point and extending away from the chain guide and ending at a third pivot point; a third link beginning at the second pivot point and extending away from the chain guide and parallel to the second link, connected to a fifth pivot point at an intermediate position along the third link and ending at a fourth pivot point; a fourth link beginning at the fourth pivot point, connected to the third pivot point at an intermediate position along the fourth link and ending at a sixth pivot point; a fifth link extending from the fifth pivot point toward a seventh pivot point; and a sixth link fixed to the attachment mechanism extending between the sixth and seventh pivot points.