US 5,102,372 A · Bicycle derailleur cable actuating system

Abstract

A bicycle derailleur gear shifting system having a rotatable handgrip actuator cam which is coupled with the derailleur shifting mechanism through a control cable system so as to control the derailleur mechanism. Separate actuator cams are associated with the front and rear derailleurs. For the down-shifting direction, at least the rear derailleur cam is configured so as to substantially compensate for increasing force of the derailleur return spring; so as to substantially compensate for numerous cumulative lost motions in the derailleur shifting mechanism and cable system; and so as to overshift the chain a sufficient amount beyond the destination freewheel sprocket so that the chain will approach the destination sprocket in the same direction as it would in the up-shift direction, but not sufficient to cause a double shift, or derailling from the #1 sprocket. A front derailleur cam is configured to provide fine-tuning for "cross-over" riding.

Claims18

Dependent claims

A bicycle gear shifting system, which comprises:

derailleur shifting means having return spring means operatively associated with the rear wheel of the bicycle;
handgrip shift actuator means comprising a rotatable portion mounted on the bicycle handlebar generally coaxially of the handlebar;
cam means on said rotatable portion of said shift actuator means;
control cable means having one end fixedly secured relative to said handlebar and the other end operatively connected to said derailleur shifting means, said cable means being biased toward said derailleur shifting means by said return spring means;
said cam means comprising cam lobe means over which said cable means is looped;
said cam lobe means being configured so that movement thereof in one direction will cause said cam lobe means to pull said cable means against the biasing force of said spring means so as to cause down-shifting of said shifting means, and rotation thereof in the opposite direction will release said cable means in the direction of the biasing force of said spring means so as to cause up-shifting of said shifting means.

3 more elements

Dependencies are inferred from the claim text.

Bicycle derailleur cable actuating system

Life of this patent

Bicycle derailleur cable actuating system

Life of this patent

Abstract

Claims18