BICYCLE TRANSMISSION DEVICE

摘要

A bicycle transmission device basically includes an input rotational shaft, an output part, a transmission mechanism that accelerates a rotational input that is input from the input rotational shaft and outputted to the output part, and a switching mechanism that selectively engages and disengages the transmission mechanism between the input rotational shaft and the output part. The transmission mechanism has first, second, third and fourth rotating bodies. The first rotating body is rotatable with the input rotational shaft. The second rotating body rotates around a stationary center axis with respect to the input rotational shaft and to which the torque of the first rotating body is transmitted. The third rotating body rotates with the second rotating body. The fourth rotating body receives torque from the third rotating body and rotates with the output part.

主权项

1. A bicycle transmission device comprising:
an input rotational shaft; an output part; a transmission mechanism configured to accelerate a rotational input from the input rotational shaft and output the rotation input to the output part; and a switching mechanism configured to selectively switch between a first state, in which the output part and the input rotational shaft are operatively coupled together to transmit the rotational input via the transmission mechanism, and a second state, in which the output part and the input rotational shaft are operatively coupled together without accelerating the rotational input from the input rotational shaft to the output part via the transmission mechanism, the transmission mechanism comprising:
a first rotating body integrally rotatable with the input rotational shaft;a second rotating body rotatable around a center axis whose position does not change with respect to the input rotational shaft, and to which the torque of the first rotating body is transmitted;a third rotating body that is integrally rotatable with the second rotating body; anda fourth rotating body to which the torque of the third rotating body is transmitted and that is integrally rotatable with the output part.