Zf Friedrichshafen Ag

Otto Lutz

Franz Sorg

Peter Muschel

Roland Leibinger

Markus Eisele

Harry Nolzen

Torsten Buchner

In a gearbox control system () for detecting systematic errors and long-term changes, the behavior of a real gearbox () is compared to the behavior of an ideal gearbox (), which is implemented in the form of a gearbox model in the gearbox control system ().

Gearbox control system

A control valve () comprises a housing () manufactured by a pressure die casting process, whose housing edges of upper semicircular bore hole are located exactly vertically above housing edges of lower semicircular bore hole and for this reason, the mold slide that forms the control edges () no longer has any contact point with the housing () and, as a consequence, symmetrical control edges () arise.

Regulator valve

A method for determining characteristic parameter values within a transmission that includes, for example, hydraulically-operated shifting elements, hydro-dynamic brakes, and hydro-dynamic torque converters. Slip regulation is used to determine the actual slip at a transmission element, whose characteristic parameter values are to be determined, before engagement. This element to be adapted is activated by means of pressure application, and thus a specified slip is set that is clearly different from the actual slip at lower torques. The applied pressure or flow may be determined from the set slip, and occurrence of a set slip allows the occurring pressures to be determined.

Method for determination of characteristics of a transmission

Within the scope of the method for motor reduction while closing the lock-up clutch for automatic transmission of a motor vehicle, the starting value of the motor reduction is brought up via an adjustable ramp within the time period elapsed while laying on the disks of the lock-up bridge clutch, the motor reduction being adjustable with reference to a characteristic field.

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Meersburg, Germany

Otto Lutz