Motion transmitting device

Abstract

A motion transmitting device for transferring rotary motion with high efficiency and very large speed ratios and at speed ratios very close to unity. A rigid cylindrical outer member contains a flexible, spring-like inner member having a larger outer circumference than the inner circumference of the outer member, thus causing at least one area of separation or disengagement where the flexible inner member is forced inwards away from the outer member. Drive means are provided by a third member which cause the area or areas of disengagement to move around the interface between the inner and outer members producing a rotation of the inner member in a precessing fashion in the same direction as the area of disengagement with respect to the outer member, but at a much reduced rate. The rate of movement of the inner member with respect to the outer member is proportional to the ratio of the difference between the outer circumference of the inner member and the inner circumference of the outer member to the inner circumference of the outer member. The mating surfaces of the inner and outer members may be provided with gear teeth of the same pitch with the inner member having a slightly larger number due to its larger size. The mating surfaces may also be smooth or roughened depending upon the friction desired to prevent slipping at least up to a predetermined torque.

Dependencies are inferred from the claim text.