Internal Transmission Speed Rpm Sensor, Component Description - GF27.19-D-1114HAG
TRANSMISSION 722.9 in MODEL 906
Electric controller unit (Y3/8) viewed from left
Location
The internal transmission RPM sensor is positioned on the electric controller unit.
Task
The internal transmission RPM sensor acquires the RPM of the sun gear of the Ravigneaux gear set via the external plate carrier of the multidisk clutch K1. Together with the information from the turbine wheel RPM sensor and from the output speed sensor this is processed as input signals by the control unit (Y3/8n4). This contributes to shortening the reaction time during shift operations.
Design
The internal transmission speed RPM sensor is firmly fixed to the electric controller unit and cannot be replaced individually.
Function
A permanently magnetized pole wheel (cylinder flange with integrated ring magnet) and the internal transmission speed RPM sensor, which consists of magnetoresistive elements, are used to detect the internal transmission speed. A magnetoresistive element changes its resistance under the influence of a magnetic field. The cylinder flange with integral ring magnet is connected to the ring gear of the rear single planetary gear set. Magnetic field changes occur due to the rotary motion of the ring gear and as a result a resistance change occurs in the magnetoresistive elements. An electronic analysis system forwards this information to the control unit. By using this speed recording system the measurement can take place over a greater distance than with the Hall sensor.