Patent ID: 8979707
Filing Date: 2015-03-17
Classification: F16H,Y10T

Abstract:
1. A method of operating a drive-train of a motor vehicle in which the drive-train comprises an automated shift transmission, between a drive aggregate and an axle drive, with at least one unsynchronized main transmission and a synchronized downstream group, drivingly coupled downstream from the main transmission, and an input shaft of the automated shift transmission being connected with the drive aggregate by way of a controllable separator clutch and an output shaft of the automated shift transmission being connected to the axle drive, the method comprising the steps of: when the motor vehicle is being driven and the main transmission adopts a neutral position and if a malfunction develops in the drive aggregate such that the aggregate stops or cannot be controlled, then operating the drive-train to engage a gear, on the one hand, by bringing the downstream group to a non-power-flow transmitting position such that the downstream group coasts to a stop, and, on the other hand, applying a shifting impulse to a shifting cylinder of the main transmission such that shifting elements of the main transmission ratchet over one another until the shifting elements mesh due to the decreasing rotational speed difference and thereby engaging the main transmission, and bringing the downstream group to a power-flow-transmitting position once the main transmission is engaged.