PROCESSO E DISPOSITIVO PARA DISTINGUIR ENTRE DE UM LADO TUBERCULOS VEGETAIS E DE OUTRO LADO PEDRAS E TORROES OU GRUMOS DE TERRA

A method and apparatus for distinguishing and separating both stones and soil clods from field crops, in which a sensor (5) is simultaneously responsive to both impact and influence on a sensor-generated magnetic field and generates output signals characteristic of field crops, stones and clods. The output signals are fed to electronic circuitry (12) that distinguishes output signals produced by mechanical impact of stones and those produced by passage of clods through the magnetic field from signals generated by crops. An ejector cylinder (15) and ejector (16) separates stones and clods from crops upon receipt of a signal from the electronic circuitry.