| 摘要 |
A harvester of the type comprising a pick-up mechanism operative to gather harvested material from the ground and to supply the same to a conveying structure within the harvester is further provided with a metal detector located within the harvester between the pick-up mechanism and conveying structure. The metal detector comprises a non-conductive shield structure which is disposed adjacent the path of movement of material passing from the pick-up mechanism to the conveying structure and arranged to provide a surface over which said material passes, and sensor means mounted within the shield structure and operative to produce a field which penetrates said surface and extends transversely across the path of movement of material being supplied by the pick-up mechanism to the conveying structure. The sensor means preferably operates to generate a high frequency oscillating field which is interrupted by the presence of metal objects in the material being fed to the conveying structure, with the field interruption producing a signal which shuts the harvester down. |
