PTO SHAFT MONITORING APPARATUS

摘要

A tractor is disclosed having a PTO shaft and different types of stub shaft for connecting the PTO shaft to different types of implement to be driven by the PTO shaft, A circumferentially discontinuous tone wheel is provided on the PTO shaft and a sensor is associated with the tone wheel for generating, in response to rotation of the tone wheel, an electrical signal having a waveform that repeats with a frequency indicative of the speed of rotation of the PTO shaft. In the invention, different formations are provided on different stub shaft types, and the formation on at least one type of stub shaft is detectable by the sensor associated with the tone wheel and serves to modify the repeating waveform generated by the sensor in a manner indicative of the type of the stub shaft.