Patent ID: 6258005
Filing Date: 2001-07-10
Classification: B62M

Abstract:
A multispeed gearshift mechanism for bicycles, comprising: a shaft (1), which can be mounted, fixed against relative rotation, on a bicycle frame, an actuator (7), rotatably seated on the shaft (1), a shell (12), rotatably seated on the shaft (1), a gearshift mechanism, which is provided with a first and a second planetary gear (15, 16, or respectively 80, 81), is arranged in the shell (12) and coupled with the actuator (7) and the shell (12), for making available several gear ratios between the actuator (7) and the shell (12), wherein the planetary gears (15, 16, or respectively 80, 81) at least have respectively two sun wheels (19, 20, 22, 23, or respectively 84, 85, 88, 89), which are coaxial in relation to the shaft (1), at least one planet carrier (17, 82, 86) with appropriately stepped planet wheels (18, 21, or respectively 83, 87), which are in engagement with the sun wheels (19, 20, 22, 23, or respectively 84, 85, 88, 89), and at least one ring gear (24, 25, or respectively 94), which is in engagement with the planet wheels (18, 21, or respectively 83, 87), and having a shifting device for selecting the gear ratios by the selective connection of the sun wheels (19, 20, 22, 23, or respectively 84, 85, 88, 89) with the shaft (1), characterized in that the the shifting device has means (31, 32 or, respectively, 95, 96) for the selective connection of the ring gear (24, 25) of the first and/or second planetary gear (15, 16) with one of the sun wheels 19, 22) of the same planetary gear (15, 16) or for the selective connection of the planet carrier (82, 86) of the first and/or second planetary gear (80, 81) with one of the sun wheels (84, 88) of the same planetary gear (80, 81).