Patent ID: 7892144
Filing Date: 2011-02-22
Classification: F16H,Y10T

Abstract:
1. A method of operating of a drivetrain of a motor vehicle having at least a drive motor and an automatic transmission with at least five shift elements, the method improving a shift speed of at least one of a successive upshift and a successive downshift, such that during a first upshift or a first downshift, at least one shift element, required for the respective successive upshift or the successive downshift, is prepared such that when a synchronization point of the first upshift or the first downshift in progress is reached, the successive upshift or the successive downshift can be immediately carried out, the method comprising the steps of: requiring, at most, two of the at least five shift elements to be disengaged and a remainder of the at least five shift elements to be engaged, in each of a plurality of forward and reverse gears, for transferring torque and force, and two respective consecutive upshifts or two respective consecutive downshifts are accomplished with at least some overlap; defining the first upshift and the first downshift as a multiple gearshift; preparing the successive upshift or the successive downshift during the first upshift or the first downshift, the successive upshift or the successive downshift being one of a single gearshift or a multiple gearshift; disengaging a first of the at least five shift elements and engaging a second of the at least five shift elements during the first upshift or the first downshift; preparing a third of the at least five shift elements, during the first upshift or the first downshift, for disengagement in the successive upshift or the successive downshift; preparing a fourth of the at least five shift elements, during the first upshift or the first downshift, for engagement in the successive upshift or the successive downshift; at least partially retaining at least a fifth of the at least five shift elements during the first upshift or the first downshift and during the successive upshift or the successive downshift; and one of increasing and decreasing a torque of the drive motor, relative to a torque of the drive motor derived from a driver's wish, during at least one of the first upshift or the first downshift and the successive upshift or the successive downshift to assist in overlapped implementation of the successive upshift or the successive downshift.