BMW E61 Sports Wagon 530xiT, Руководство пользователя

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Adjusting Levers
The actuator drive unit operates such that the drive pinion rotates and engages via the
gearing in the control cam. In turn, the control cam is rotated and the control lever
pressed apart.
The rotary motion is converted into an axial force by the ball ramps in the control lever.
The axial force that compresses the disc package in the multi-disc clutch is proportional
to the transmitted torque of the multi-disc clutch.
The position of the control lever is infinitely variable and allows exact regulation of the
control cam by the actuator drive unit.
Servomotor with Motor Position Sensor
The actuator drive unit is a DC motor with worm drive. It also features a Hall sensor that
serves the purpose of determining the position and the adjustment speed of the motor
shaft. The position of the motor shaft determines the closing rate of the multi-disc clutch.
There is also a temperature sensor installed in the motor that signals the temperature to
the transfer case control unit (VGSG). A temperature model is calculated in the VGSG for
the purpose of protecting the motor from overload. For this purpose, the maximum clos-
ing rate is reduced in various stages.
If these measures are not sufficient to protect the motor from overload, the control is
interrupted and the clutch completely opened so that only rear axle drive is now possible.
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E61 Sports Wagon
Index Explanation
1
Magnetic ring
2
Motor position sensor (Hall sensor)