Gearbox for aligned shafts, used for bicycles

摘要

The gearbox is composed of a drive plate (2) and a driven plate (3) freely rotating about a common axis. The plates have opposite projecting toroidal surfaces (7) with circular and coaxial teeth (8). There is a central non rotating support. Several support cradles (5,9) for transmission of movement between the plates are pivoted on the central support and carry a pinion (4) meshing with the plate teeth. The support cradles rotate together by means of a connector (25). A speed selector controls pivoting of one of the cradles. The drive and receptor plates are separated by a constant distance. The hubs and rims of the plates have slots which favour transverse bending of their teeth. One of the plates is made of deformable elastic material and is mounted so that its periphery deforms elastically opposite the other plate.