GF27.60-P-4013SXA Shift From 1 to 2, Function

GF27.60-P-4013SXA Shift from 1 to 2, function
- Transmission 722.6

Component Identification:

Aim
Activate multi-disk clutch K1, deactivate multi-disk brake B1.

Function

1st gear engaged
The end face of the 1-2/4-5 command valve is kept depressurized via the 1-2 and 4-5 shift solenoid valve. The holding pressure shift valve 1-2/4-5 applies working pressure to the multi-disk brake B1. The multi-disk clutch K1 is unpressurized.

Shift phase
The 1-2 and 4-5 shift solenoid valve shifts the shift valve pressure such that it impinges on the end face of the command valve 1-2/4-5. In turn the command valve 1-2/4-5 is displaced and the shift pressure coming from the shift pressure shift valve 1-2/4-5 routed over the command valve 1-2/4-5 to the multi-disk clutch K1. At the same time the multi-disk brake (B1) is subjected to overlap pressure from the 1-2/4-5 overlap regulating valve.

The pressure acting on the end face of the shift pressure shift valve 1-2/4-5 from multi-disk brake B1 is replaced by the working pressure. The increasing shift pressure at the multi-disk clutch K1 acts on the ring surface on the overlap regulating valve 1-2/4-5 and reduces the regulated overlap pressure from the overlap regulating valve 1-2/4-5. At an appropriate pressure level on the 1-2/4-5 holding pressure shift valve this valve switches over.

2nd gear engaged
After gear change is complete, the pressure on the end face of the 1-2/4-5 command valve is reduced via the 1-2 and 4-5 shift solenoid valve and the command valve is pushed back into its original position. The working pressure is now routed from the holding pressure shift valve 1-2/4-5 and command valve 1-2/4-5 to the multi-disk clutch K1.

The multi-disk brake B1 is deactivated (unpressurized). The spring in the 1-2/4-5 shift pressure shift valve pushes this into its original position.