Hypocycloidal Gear Train for Varying the Speed Between Two Shafts and a Bicycle Having Such a Hypocycloidal Gear Train

摘要

A hypocycloidal gear train for transmitting power between two coaxial shafts, one of which is the driving shaft (1) and the other the driven shaft (2), so that the input speed transmitted by the driving shaft (1) is different to the output speed transmitted to the driven shaft (2), and a bicycle having such a hypocycloidal gear train, where the hypocycloidal gear train comprises: ;a transmission element (3) to be rigidly connected to the driving shaft (1), ;at least one ring gear (4), having toothing inside and being fixed relative to all of the other components of the hypocycloidal gear train, ;a planetary gear (5), having several sets of toothing, one of these sets of toothing meshing with the ring gear (4) toothing, the planetary gear being rotatably connected to the transmission element (3) and under the action applied to it by the transmission element during driving shaft (1) rotation, the planetary gear rolls without sliding on the ring gear (4) toothing, so that the tips of its toothing are forced to move along a hypocycloid, ;a plurality of gears (6), each meshing on one side with a respective set of toothing of the planetary gear (5) and on the other side designed to be rigidly connected to the driven shaft (2), ;a slider part (8), inserted between the plurality of gears (6) and the driven shaft (2) and able to move along the longitudinal direction of the driven shaft (2) between a plurality of positions, in each of which it on each occasion rigidly connects one of the gears (6) and the driven shaft (2).