Under the switching device for automatic switching processes selection mode suppression of a mechanical gear unit with semi-automatic circuit.

摘要

A control system (104) for semi-automatically executing automatically and manually selected upshifts and downshifts of a mechanical transmission system (10) is provided. The control system includes a central processing unit (106) for receiving input signals indicative of transmission input shaft (16) and output shaft (90) speeds, from a driver control console (108) indicative of manual selection of upshifts or downshifts from a currently engaged gear ratio, or manual selection of operation in an automatic preselect mode, and from a sensor (150) to sense operator manual issuance of shift enable signals, 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 caused torque reversal of the transmission and manual substantial synchronization of the transmission in the selected ratio thereafter. Under certain conditions, such as relatively high or relatively low vehicle speed, implementation of automatically preselected shifts is prohibited until a shift enable signal is received.