Process and device for controlling a gearsift of an automatic gearbox

Abstract

The invention relates to a control process for an automatic gear box which permits gears to be shifted, in particular downshifted, with minimum interruption of tractive power. The phase in which the driving moment of the propulsion engine is reduced, the phase in which the frictional connection in the automatic gear box is interrupted, and the phase in which the rotational speed of the gear box input shaft is adapted to a suitable target rotational speed are designed in such a way that they overlap in time at least in part. In particular, when the frictional connection is interrupted in the automatic gear box, the propulsion engine transmits over the clutch a driving moment to the input shaft of the automatic gear box, causing a change in the rotational speed of the gear box input shaft (n_ge) which tends towards the synchronous rotational speed of the new gear.; The invention also relates to a device for carrying out this process.

Description

technical field

[0001] The invention relates to a method for controlling shifting of an automatic transmission according to the preamble of claim 1 and to a device for carrying out the method. Background technique

[0002] Automatic transmissions have long been used on different types of cars. In the case of a manual transmission, the driver coordinates several devices temporally and as the case may be when changing gears, while an automatic transmission frees the driver from these operations and thus allows him to concentrate better. focus on traffic conditions.

[0003] Of course, an experienced car driver executes shifting in a number of ways by timing the engagement of the clutch and accelerator pedals, by the timing and speed at which the shift lever is operated, and by the force applied to the shift lever at the same time. file process and optimize it corresponding to his then intentions. For example, if he wishes to change gears particularly comfortably and without...