Start control device of power transmission system for vehicle and start control method

摘要

A start control device and a start control method of a vehicular power transmission system including a lock-up clutch and a start clutch are provided in which start-time lock-up slip control is performed, and neutral control is performed. When the start-time lock-up slip control is additionally executed during cancellation of the neutral control, the gradient of an output rotational speed of the hydraulic power transmission which is changed, through engagement of the start clutch, toward an input rotational speed of the automatic transmission at the time of completion of engagement of the start clutch is controlled, using at least one of a start clutch pressure that is increased so as to engage the start clutch, and a lock-up clutch pressure that is increased so as to bring the lock-up clutch into slip engagement.

主权项

1. A start control device of a power transmission system for a vehicle including a lock-up clutch capable of directly coupling input and output members of a hydraulic power transmission that transmits power of an engine to an automatic transmission, and a start clutch that transmits the power of the engine toward driving wheels when placed in an engaged state, comprising:
a controller that performs start-time lock-up slip control for bringing the lock-up clutch into slip engagement when the vehicle is started, and performs neutral control for placing the start clutch in at least one of a slipping state and a released state when the vehicle is stopped so as to bring a power transmission path between the engine and the driving wheels into a restricted power transmitting condition, wherein when the start-time lock-up slip control is additionally executed during cancellation of the neutral control, the controller controls a gradient of an output rotational speed of the hydraulic power transmission which is changed, through engagement of the start clutch, toward an input rotational speed of the automatic transmission at the time of completion of engagement of the start clutch, using at least one of a start clutch pressure that is increased so as to engage the start clutch, and a lock-up clutch pressure that is increased so as to bring the lock-up clutch into slip engagement.