oil AUDI A6 ALLROAD 1999 C5 / 2.G Pneumatic Suspension System

25
The rotor consists of a closed conductor loop
connected to the sender arm (rotates with the
sender arm). The conductor loop has the
same geometric shape as the receiver coils.
Construction/design
The angle sensor consists essentially of the
stator and the rotor.
The stator consists of a multilayer circuit
board comprising the exciter coil, three
receiver coils and the control/evaluation
electronics. The three receiver coils have an
angular geometrical star shape and are
arranged out of phase. The exciter coil is
mounted on the back of the circuit board.
243_035
Operating lever
Conductor loop/rotor
Front of multilayer circuit board
with view of the receiver coils
Circuit board
connectors
Rear of multilayer circuit board
with view of the exciter coil
Control/evaluation
electronics

26
System components
Function
The exciter coil is subjected to an alternating
current which produces an electromagnetic
alternating field, the induction of which is
penetrated by the rotor.
The current induced in the rotor produces a
second electromagnetic alternating field
around the conductor loop (rotor).
Both alternating fields, from the exciter coil
and from the rotor, act on the receiver coils
and induce corresponding alternating
currents in them.
While the induction of the rotor is
independent of its angle position, induction
of the receiver coils depends on their
distance from the rotor and thereby on its
angle position.
As the rotor, depending on its angle position,
overlaps differently with regard to each
receiver coil, their voltage amplitudes vary in
accordance with the angle position of the
rotor.
The evaluation electronics compensate the
alternating currents of the receiver coils,
amplify them and produce proportional
output voltages for the three receiver coils
(proportional measurement). After voltage
evaluation, the result is converted into output
signals for the level sensors and transmitted
to the control units for further processing.
0
0
0
243_036
243_037
Exciter coil
Stator
Rotor
3 receiver coils
Conductor loop
(induced current)
U
1
U2
U3
Voltage amplitudes depending on the position of
the rotor with regard to the receiver coil
(example of a rotor position)
U1
U2
U3
Time
Time
Time
1st magnetic
field at the
exciter coil
2nd magnetic
field in the
conductor loop