DEUTZ-FAHR AGROTRON 106 MK3, Руководство по ремонту

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3. When the lift is lowered
•
During lifting or when the lift is stationary, the spool (8) is pushed to the right by the spring (9).
•
As a result, the passage between the chambers m and n is closed and the pressure in chamber p pushes the spool
(10) to the right.
When the lift is lowered, the electronic lift control energises the solenoid (7) that moves the spool (8) to the left.
The oil in chamber
n can flow into chamber m and the pressure in chamber p is reduced.
•
Now the force balance coming from the pressure in the chambers e and p influencing the spool (10), is disturbed and
moved to the left. Oil can flow now from e to m .
•
As a result, the oil in the lift cylinders is directed to the drain circuit and the lift is lowered.
•
As the solenoid is of the proportional type, the more current supplied, the more the spool (8) shifts to the left, thereby
allowing more oil to flow and the lift to descend more rapidly.
•
The electronic control obtains float position by energising the solenoid valve (7) and holding it fully open.
•
In this condition, the oil in the lift cylinders is sent to the drain circuit so that the lift is free to move up and down and
follow the contours of the terrain.
D0004950
7
8 9
p
10
e n m
R A
P
R A
HYDRAULIC SYSTEM AUXILIARY SERVICES CONTROL VALVE