| 摘要 |
The disclosed device controls a cable associated with a bicycle gearshift and is particularity configured for securing the body of the device on the forward-facing end of racing bicycle handlebars. A cable winding bobbin, having an internally toothed crown, is provided in the device's body and a drive mechanism rotates the bobbin in the chosen direction to achieve predetermined angular positions. A ratchet mechanism, located between the lever and the toothed crown, includes opposite rocker arms with cam profiles curved away from each other, and a toothed sector for engaging the toothed crown. A pointer is located to be selectively engaged with at least one of the rocker arms so that engagement results in the rocker arm's toothed section being away from the toothed crown, and disengagement results in the rocker arm's toothed section being engaged with the toothed crown. |
| 主权项 |
1. An actuation device for a control cable for a bicycle gearshift, comprising:
a casing, configured for attachment on an end of a handlebar of the bicycle, a bobbin on which to wind the cable, angularly mobile in the casing around a main axis of the device, a drive mechanism, acting on the bobbin to rotate the bobbin in a first and in a second angular direction around the main axis of the device, indexing means to removably hold the bobbin in predetermined angular positions, the drive mechanism comprising: a lever that is biased towards a neutral position, angularly mobile with respect to the casing around the main axis of the device, in the first or in the second angular direction from the neutral position to obtain downward or upward gearshifting, an internally toothed crown, non-rotatably mounted to the bobbin and angularly mobile in the casing, elastic means acting between the lever and the casing that bias the lever into the neutral position, and a ratchet mechanism between the lever and the toothed crown that comprises: two opposite rocker arms, hinged on the lever according to two pivot axes parallel to one another and to the main axis of the device, each of said rocker arms having an arched shape wrapping around the main axis of the device and extending from a first end to a second end, wherein the first end of the first rocker arm is proximal to the first end of the second rocker arm and the second end of the first rocker arm faces towards the second end of the second rocker arm, a toothed sector, formed on each rocker arm on an outer side thereof, proximal to the respective second end, said sector having a toothing profile for engaging the toothing of the toothed crown, wherein the crown is in an axial position corresponding to that of the toothed sectors along the main axis of the device, a cam profile, formed on each rocker arm on an inner side thereof, adjacent to the respective first end, a thruster to thrust each rocker arm around a pivot axis of the rocker arm to thrust the second end of each of the rocker arms away from the main axis of the device, a pointer that is stationary with respect to the casing and facing radially outwards with respect to the main axis of the device, engaged with at least one cam profile on the rocker arms, each cam profile is configured such that: when the pointer is engaged with the cam profile of one of the rocker arms, the toothed sector of the one rocker arm is positioned away from the toothed crown, and when the pointer is disengaged from the cam profile, the toothed sector of the one rocker arm is thrust into engagement with the toothed crown by the thruster. |
