Control Method for Output Speed during Velocity Ratio Change under High Rotational Speed Using an Uninterrupted Transmission System

Transmissions that can change their velocity ratio are used in various mechanical devices to achieve a wide range of torques or speeds. For machines with transmissions, such as transportation vehicles, it is required to keep the output speed or the output acceleration constant even during the velocity ratio changing process in order to transport the passengers or goods smoothly. Therefore, a method of velocity ratio change is required that can keep the output shaft at a constant speed or a constant acceleration. However, this is impossible in geared transmissions because they cause an interruption in the power transmission during the velocity ratio changing process. To solve this problem, a novel method of making the output shaft rotate at a desired speed even during the velocity changing process using an uninterrupted transmission system with noncircular gears is proposed in this study. Theoretical analysis is performed to clarify the appropriate input speed required to realize the desired output speed. A method of changing the velocity ratio under high rotational speed is proposed. An experimental device of the novel uninterrupted transmission system is constructed. An experiment to control the output speed during the velocity ratio change is performed under high rotational speed, and the effectiveness of the proposed method is verified.