GF27.60-P-4014GZ Shifting N to D (1st Gear), Function

GF27.60-P-4014GZ Shifting N to D (1st gear), function
- Transmission 722.9


In the "N" position of the gear selector switch for DIRECT SELECT (S16/13) the multi-disk brake B3 and multi-disk clutch K3 are engaged. By shifting from position "N" to position "D" the supply to multi-disk brake B2 is released by the selector valve. The fully integrated transmission control (VGS) control unit (Y3/8n4) actuates the brake control solenoid valve B2 (VGS) (Y3/8y6) and the multi-disk brake B2 is filled with transmission oil.

The rpm difference (actual slip) of the engine speed relative to the turbine speed is used by the fully integrated transmission control (VGS) control unit to determine whether the multi-disk brake B2 is filled. The brake control solenoid valve B2 (VGS) actuates the regulating valve B2/BR which converts the applied working pressure into shift pressure and passes it on to the multi-disk brake B2.

The slip required (specified slip) for each gear is stored in the fully integrated transmission control (VGS) control unit. Depending on this the brake control solenoid valve B2 (VGS) changes the control pressure on the regulating valve B2/BR. The shift pressure produced by the regulating valve B2/BR depends on the geometry of the regulating valve B2/BR. The pressure in multi-disk brake B2 is then continually altered until the specified slip stored in the fully integrated transmission control (VGS) control unit is reached.