摘要 |
A hybrid transmission system for use in internal combustion engine vehicles provides two modes of vehicle operation. In the first or city mode, the vehicle is propelled by one or more reversible hydraulic motor/pumps which operate as a function of vehicle accelerator pedal displacement and of brake pedal displacement and which are driven by fluid pressure stored in an accumulator. In the second or highway mode, the vehicle is propelled by its internal combustion engine through a mechanical transmission. During the city mode operation, the accumulator is automatically and intermittently charged by a reversible hydraulic motor/pump driven by the internal combustion engine. Also, during the city mode, the internal combustion engine operates only during intermittent charging of the accumulator. The hybrid transmission system has automatic regulating units to control the accumulator charging process, to regulate the brake fluid pressure within the master brake cylinder to insure that vehicle braking is solely a function of brake pedal displacement, and to control which reversible hydraulic motor/pump(s) is (are) utilized during the city mode operation. Additionally, the hybrid transmission system utilizes a manually operated mode/selection device to allow the vehicle operator the choice of first or second mode vehicle operation. |