Patent ID: 6048287
Filing Date: 2000-04-11
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 planet wheel gearshift mechanism (15, 16, 35) arranged in the shell (12) and connecting the actuator (7) and the shell (12) with at least one sun wheel (19, 20, 22, 23) rotatably seated on the shaft (1), a ring gear (24, 25, 39), a planet carrier (17, 37) and a planet wheel (18, 21, 38) rotatably seated on the latter, and a clutch device (26, 27, 28, 29) for providing at least two gear ratios between the actuator (7) and the shell (12), wherein the clutch device (26, 27, 28, 29) has a tooth arrangement (77), a selector ratchet (74) and a rotatably seated actuating member (76) intended for controlling the latter, which can be operated from the outside, in such a way that for selecting the gear ratios the selector ratchet (74) can be selectively put into engagement with the tooth arrangement (77) or disengaged therefrom, that the tooth arrangement (77) is provided on the sun wheel (19, 20, 22, 23), the shaft (1) has a section (1c), which is designed as a hollow body and receives the actuating member (76), and the selector ratchet (74) is seated in an opening (83) of an outer wall (81), delimiting the hollow body, of this section.