A Hydromechanical Transmission Optimized for Automotive Application

The application of hydromechanical continuously variable transmission technology to a wide variety of automotive applications is made feasible by a unique design approach. Analysis indicates that the basic design scales readily to accommodate power inputs of under 7.5 KW to over 750 KW. The first prototype has been targeted to compete in the mid-range truck and bus market segments with transmission input torques in the order of 850 N.m to 1300 N.m and a maximum torque multiplication of approximately 10:l. The problems of high cost, poor efficiency and excessive noise which prevented prior hydromechanical units from gaining acceptance for automotive applications have been eliminated or reduced to acceptable levels in the new design.