27-9170 Shift pressure
The shift pressure influences the shift quality when clutches K1 and K2 and brake band B1 are engaged and disengaged.
The shift pressure acts in the spring chambers of dampers K1, K2 and in damper B1.
The shift pressure is derived from the working pressure and is controlled at the shift pressure control valve (47).
The shift pressure acts on the end face (c) and pushes the control valve (47) against the modulating pressure "M1" into the control position. This causes the working pressure inlet at the control edge (a) to be restricted and the zero discharge to be opened to reduce the pressure.
The level of the shift pressure is determined by the modulating pressure "M1" and by the force of the spring.
This means:
low modulating pressure =low shift pressure
high modulating pressure =high shift pressure
Shift pressure system; valve in control position
47 Shift pressure control valve
A Working pressure
M1 Modulating pressure M1
SD Shift pressure
S2 Control pressure S2
0 Oil sump discharge
a Control edge
b Control surface
c End face
P27-5034-13