Metal detector for monitoring unwanted metallic particles in product e.g. food, flow, has circuit stage assigned to sensor signal, and reducing amplification to small valve during exceeding of value dependent on permissible maximum value

摘要

The detector has individual sensors whose signals are controlled by a sensor signal-operational amplifier (OP). A conditional run time difference between the signals is balanced by distance of the sensors and the conveying speed of a product flow. A summation circuit is provided for arithmetic addition of signal rates that depend on a metallic conducting particle in a conveying material flow. A circuit stage is assigned to the individual signal and reduces the over all amplification to a smaller valve during exceeding of the value dependent on a permissible maximum value.