Deere & Company
Multi-mode starter-generator device transmission with single valve control

Abstract:

A power control system is provided for a work vehicle with an engine. A combination starter-generator device has an electric machine and a gear set configured to receive rotational input from the electric machine and the engine and to couple the electric machine and the engine in two power flow directions. The gear set operates in one of multiple relatively high-torque, low-speed start gear ratios in one direction, including a first start gear ratio corresponding to a cold engine start mode and a second start gear ratio corresponding to a warm engine start mode, and in a relatively low-torque, high-speed gear ratio in another direction corresponding to a generation mode. First and second clutch assemblies are selectively coupled to the gear set to effect the start gear ratios during the engine start modes. A control valve is fluidly coupled to selectively apply a fluid pressure to the clutch assemblies.