Abstract
A noble wedge ring type roller speed reducer with the speed ratio of 25 was developed. The normal force was given in accordance with the applied torque by producing a wedge between the loading ring and output ring, which enables to exclude the additional normal force mechanism. The power transmission performance was evaluated using the traction fluid under the test conditions such as step torque, step speed and sweep torque methods. As a result, the reduction speed ratio was stable under the test conditions, while the efficiency was about 90% at the maximum output torque.
