ENHANCEMENTS TO HYDRO-MECHANICAL VEHICLE TRANSMISSION USING FIXED-DISPLACEMENT PUMP/MOTORS

摘要

Improvements to a hydro-mechanical transmission based on fixed displacement pump/motors rather than variable displacement pump/motors are disclosed. These include rpm-changing gears on the input and the output pump/motors which allow the pump/motors to be operated at their maximum rated rpm and facilitate compact packaging. A novel selectable clutch configuration is part of the packaging arrangement. The addition of a two-speed all mechanical transmission on the output extends the useful range of a mechanical bypass of the hydraulic transmission intended for cruising.