Patent attributes
A hybrid vehicle powertrain assembly includes a combustion engine, an electric machine, an input shaft, a ratchet mechanism, and a controller. The input shaft selectively couples the engine and electric machine. The ratchet mechanism includes a base integrated with a transmission housing, a camwheel fixedly coupled to the input shaft, a pawl, and an actuator to move the pawl. The controller is programmed to, in response to receipt of an engine brake command, output an engagement command to the actuator to move the pawl toward the camwheel for engagement to prevent the input shaft from spinning. A method for controlling a hybrid vehicle powertrain is also provided herein. The method includes, responsive to receipt of an engine brake command, outputting via a controller a command for a ratchet mechanism to engage an input shaft coupled to an engine to prevent the input shaft from spinning.