MR293R190_881




































ELECTRONICALLY CONTROLLED HYDRAULIC SYSTEMS
Bosch ABS
38
LOCATION AND COMPOSITION
•
Speed sensor (3) and target (4)
A magnetic sensor is composed of a permanent
magnet, a polar mass and a coil.
The magnet creates a magnetic flux which is
channelled by the polar mass.
This flux is disturbed by the variation in air gap
(when a tooth passes near the polar earth),
creating an electrical voltage at the terminals of
the coil.
The sensors deliver an alternating electrical
voltage. The frequency of the signal is
proportional to the speed of the wheel.
1
Magnet
2
Field lines
3
Polar mass
4
Target
The speed sensors are mounted on the stub axle
carriers and receive information via the toothed
targets (26 teeth at the front and the rear).
Front wheels
Targets embedded in the driveshafts.
Radial, non-adjustable sensors.
Rear wheels
Targets embedded in the hubs (cannot be
removed).
Tangential, non-adjustable sensors.
DI3888
94868R
96955S
38-91