Fault detection in automatic gearboxes - includes testing vehicle on rolling road and recording conditions under which gear change occurs

摘要

A method of detecting faults in automatic gearboxes in motor vehicles includes measuring the gear box switch times when changing gear. This is carried out by monitoring rotary speeds and comparing the results against those from a known good unit. The testing takes place on a rolling road with a large moment of inertia. Engine rotary speed is measured from a transmitter connected to the distributor via a gear wheel. Gear box rotary speed is measured at the box input and output using built in transmitters connected via slip rings and gear wheels. Transmitter outputs are passed to a single channel linear pen recorder to give graphical presentation of rotary speed with elapsed time.