GF27.60-D-4013H Shift From 1 to 2, Function
GF27.60-D-4013H Shift From 1 to 2, Function
- TRANSMISSION 722.6
1st gear engaged
0 Oil sump drain
21 Multidisk brake B1
24 Multidisk clutch K1
28a 1-2/4-5 holding pressure shift valve
29a 1-2/4-5 shift pressure shift valve
30a Overlap regulating valve 1-2/4-5
31a 1-2/4-5 command valve
p-A Working pressure
p-Mod Modulating pressure
p-S Shift pressure
p-SV Shift valve pressure
Y3/6y3 1-2 and 4-5 shift solenoid valve
Shift phase
0 Oil sump drain
21 Multidisk brake B1
24 Multidisk clutch K1
28a 1-2/4-5 holding pressure shift valve
29a 1-2/4-5 shift pressure shift valve
30a Overlap regulating valve 1-2/4-5
31a 1-2/4-5 command valve
p-A Working pressure
p-Mod Modulating pressure
p-S Shift pressure
p-SV Shift valve pressure
Y3/6y3 1-2 and 4-5 shift solenoid valve
2nd gear engaged
0 Oil sump drain
21 Multidisk brake B1
24 Multidisk clutch K1
28 A 1-2/4-5 holding pressure shift valve
29 A 1-2/4-5 shift pressure shift valve
30 A Overlap regulating valve 1-2/4-5
31 A 1-2/4-5 command valve
p-A Working pressure
p-Mod Modulating pressure
p-S Shift pressure
p-SV Shift valve pressure
Y3/6y3 1-2 and 4-5 shift solenoid valve
Aim
Connect multidisk clutch K1, switch off multidisk brake B1
Function
1st gear engaged
The end face of the 1-2/4-5 command valve is held unpressurized via the 1-2- and 4-5 shift solenoid valve. Working pressure at the multidisk brake is applied via the 1-2/4-5 holding pressure valve B1. The multidisk clutch K1 is unpressurized.
Shift phase
Via the 1-2 and 4-5 shift solenoid valve the shift valve pressure is switched so that it acts on the end face of the 1-2/4-5 command valve. As a result the 1-2/4-5 command valve is displaced and the shift pressure, coming from the 1-2/4-5 shift pressure shift valve is lead via the 1-2/4-5 command valve to the multidisk clutch K1. Overlap pressure is applied simultaneously to the multidisk brake B1 from the 1-2/4-5 overlap regulating valve.
The pressure from the multidisk brake acting on the end face of the 1-2/4-5 shift pressure shift valve is superseded by the working pressureB1. The increasing shift pressure at the multidisk clutch K1 acts on the annular surface on the 1-2/4-5 overlap regulating valve and reduces the overlap pressure regulated by the overlap regulating valve 1-2/4-5. This switches over at a corresponding pressure level at the 1-2/4-5 holding pressure shift valve.
2nd gear engaged
Once the gear change is complete, pressure on the end face of the 1-5 command valve is reduced via the 1-2- and 4-5 shift solenoid valve 2/4- and this is pushed into the basic position.
Working pressure now reaches the multidisk clutch via the 1-2/4-5 holding pressure shift valve and the command valve 1-2/4-5 K1. The multidisk brake B1 is switched off (unpressurized). The spring in the shift pressure shift valve 1-2/4-5 pushes this into the basic position.
