Patent ID: 9002603
Filing Date: 2015-04-07
Classification: F16H

Abstract:
1. A method of operating a transmission device ( 1 ) of a vehicle drive-train when there is a request for a gearshift from a currently engaged gear (“ 4 ” or “ 7 ”) to a target gear (“ 5 ” or “ 8 ”), the transmission device having a plurality of frictional shifting elements (B, C, D, E) and at least one interlocking shifting element (A, F), comprising first and second mating shifting element halves, which are selectively engaged or disengaged by an electro-hydraulic actuating device to obtain various gears (“ 1 ” to “R”), the actuating device sets actuating electrical currents for electrically operated actors to specify hydraulic actuating pressures (p_A, p_B, p_C, p_D, p_E, p_F) for actuating the frictional and the interlocking shifting elements (A to F), for carrying out the requested gearshift, the at least one interlocking shifting element (F or A) has to be disengaged and at least one of the frictional shifting elements (B or C) has to be engaged, and an engaged operating condition of the frictional and the interlocking shifting elements (A to F) is recognized by determining a value of an operating condition dependent actuating current, at which the shifting element (A to F) concerned is either changed to or maintained in the engaged operating condition, the method comprising the steps of: determining the actuating currents of all the frictional and the interlocking shifting elements (A to F) while the required gearshift is being carried out to determine current operating conditions of each of the frictional and the interlocking shifting elements (A to F); testing, with a sensor device, a plausability of the current operating condition of the interlocking shifting element (F or A) to be disengaged; recognizing a fault when both: