| 摘要 |
An infinitely variable differential hydrostatic transmission utilizing a fixed displacement pump/motor and a variable displacement pump/motor interconnected with appropriate valving, to provide a mechanical/hydraulic differential drive which is capable of achieving an overall efficiency in the 98 DEG -99 DEG range. In the preferred embodiment, which utilizes axial piston type pump motors, pistons in multiples of four are utilized in order that each piston will have a piston located 90 DEG from it to serve as its control valve. The fixed and variable displacement motor/pump are provided as an integral unit containing bearing mountings, cylinder barrels, valve ports, piston seal mountings, hydraulic flow passages, pressure reservoirs and manifolding by forming a series of individual segments and sealing them together into a single structural unit. A unique mounting arrangement is utilized to positively attach the pistons to an anti-friction swashplate which eliminates all side loads on the piston. Finally, a novel piston valve seal reduces hydraulic leakage and sliding friction, and a novel pumping device is utilized for pressurizing the pump motor units and replacing fluid lost through leakage. |
