DAF CF65, CF75, CF85 Series . Manual - part 263
©
200324
3-7
Description of components
XE ENGINE COOLING SYSTEM
CF65/75/85 series
2
9
The coil (10) fitted to the drive shaft (4) with
bearings generates a magnetic field. Depending
on the variables mentioned earlier, the PWM
signal to the coil (10) will be adapted. This will
cause changes in the magnetic field and the
valve (9) will be attracted either more or less
frequently.
In static condition all silicone fluid will flow out of
the supply chamber (6), while in dynamic
condition the silicone fluid will remain in the
supply chamber (6) as a result of the centrifugal
force.
When the engine is being started, the fan will
always run for a short time, because the silicone
fluid that has settled at the bottom will be forced
outwards by the centrifugal force. Some of the
silicone fluid will first flow into the working area
(5). The silicone fluid causes friction between the
rotor (3) and the working area (5). As a result, the
difference in rotating speed (slip) between the
working area (5) and the rotor (3) will decrease.
The fan will be more and more engaged.
The silicone fluid will flow through the return
bores (11) of the working area (5), back to the
supply chamber (6).
If the valve (9) releases the opening (8) with a
certain frequency, a certain quantity of silicone
fluid will flow from the supply chamber (6) to the
working area (5). The quantity of silicone fluid
flowing through the working area, determines the
difference in rotating speed (slip) between the
working area (5) and the rotor (3).
If the valve (9) releases the opening (8) with a
higher frequency, the quantity of silicone fluid
flowing through the working area (5) will increase.
The friction between the working area (5) and the
rotor (3) will increase and the difference in
rotating speed (slip) between the working area (5)
and the rotor (3) will decrease.
M201063
10
11
4
3
8
1
2
9
7
6
5