| 摘要 |
A control system/method (104) for controlling execution of selected shifts of a mechanical transmission system (10) is provided. The control system includes a central processing unit (106) for receiving input signals indicative of engine or input shaft (11/98) speeds and of output shaft or vehicle speed (VS) speeds and from a driver control console (108) indicative of manual or automatic selection of upshifts or downshifts from a currently engaged gear ratio and processing the same in accordance with predetermined logic rule to issue command output signals to a transmission actuator (112, 70, 96) to implement the selected shifts upon a manually or automatically caused torque break of the transmission and manually or automatically caused substantial synchronization of the transmission thereafter. The predetermined logic rules include a strategy for sensing conditions indicative of a potentially dangerous downhill free-wheeling situation and for immediately causing the forced engagement of a gear ratio (GRFE) determined as a function of vehicle speed regardless of the presence or absence of substantially synchronous conditions. <IMAGE> |
