Circuit arrangement for a load power shift gear

摘要

The separating clutches (4, 5) of the two gear units (8, 10) of the power shift gear are arranged as a control point in autonomous servo-control circuits (14, 12, 4, 16 and 15, 13, 5, 17, respectively). The reference value inputs (18, 19) of the reference/actual value comparators (14, 15) of these control circuits are supplied by an electronic control unit (20) with desired value signals which run in opposite directions and increase or decrease over time. Initially, the closed clutch (4) is released except for a small degree of slip. From this time on, the clutch (5) which is to be closed is closed in a defined manner starting from the electrical image of the absolute value of the engine speed difference on both sides of this clutch by corresponding reference value stipulation (19) and simultaneously the first clutch (4) which has previously been released except for the slip is opened further in a manner defined in terms of timing by corresponding reference value stipulation (18), this procedure taking place in such a way that the sum of the absolute torques of the two clutches (4, 5) remains essentially constant. <IMAGE>