Continuously variable transmission having speed control

摘要

A continuously variable transmission system is provided having an input driving member drivable in alternating motion by a source of input mechanical energy. A ratchet having a ratcheting member and an output driven member is provided, wherein the output driven member is rotationally driven in a continuous rotational direction. A drive spring and a drive linkage are drivingly linked between the input driving member and the ratcheting member, wherein a drive force applied to the input driving member is transmitted to the ratcheting member via the drive spring and drive linkage. A return spring is drivingly linked to the ratcheting member to apply a return force to the ratcheting member. A control apparatus is further configured to selectively vary a deflection curve of the drive spring, wherein the variation in the deflection curve generally determines one or more of a rotational speed and torque associated with the output driven member.

主权项

1. A continuously variable transmission system, comprising:
an input driving member which is drivable in alternating motion by a source of input mechanical energy; a ratchet comprising a ratcheting member and an output driven member, wherein the ratcheting member is con-figured to alternate directions of motion and to rotationally drive the output driven member in a continuous rotational direction about a driven axis; a drive spring and a drive linkage drivingly linked between the input driving member and the ratcheting member, wherein a drive force applied to the input driving member is transmitted to the ratcheting member via the drive spring and drive linkage; a return spring drivingly linked to the ratcheting member, wherein the return spring is configured to apply a return force to the ratcheting member, wherein the return force is in a direction generally opposite to the drive force applied by the drive spring and drive linkage; a backup wall interacting with the drive spring; and, a control apparatus configured to selectively vary a deflection curve associated with the drive spring, wherein the variation in the deflection curve generally determines one or more of a rotational speed and torque associated with the output driven member, wherein the control apparatus further comprises a motor generally fixed with respect to the ratcheting member, said motor having a rotational output, and a coupling that operably couples said output of the motor to at least one of the backup wall and drive spring, wherein a spring constant of said drive spring may be adjusted based on a rotation of the output of the motor with respect to the coupling, said motor having an output shaft driven by said rotational output, a length of said output shaft being continuously variable and having an output end bearing against said backup wall whereby to continuously adjust said deflection curve.