Shift Actuator: Description and Operation

GF26.19-P-1005MCC Transmission Motor Selector Drum Drive Component Description

TRANSMISSION 717.480 /481 /482 /483







M17/3 Transmission motor 1
M17/4 Transmission motor 2

Location
The transmission motors are located in the transmission housing.

Task
Depending on the shift request from the automated manual transmission control unit (N15/6) the transmission motors adjust the selector drums via two-stage spur-gear unit. Actuation is pulse-width modulated by two output stages with four electronic switches each. The transmission motor is braked when the specified position is reached. It can, if necessary, be actuated with opposing voltage, if an overshoot beyond the specified position is to be prevented or reversed.

Actuation of the transmission motors is monitored by the incremental sensors, which are located on each motor shaft. These detect the rotation angle and direction of rotation of the respective transmission motor using an integrated system of Hall sensors.

Actuation of transmission motors is only required for carrying out shift operations . Upon reaching a specified position a bolt engages in the locking groove of the selector drum. This suffices to retain the selected gear.