The metal detector is used to detect foreign metal objects by using the principle of electromagnetic induction. It is widely used in food, medicine, toys, clothing, shoes, plastics and other industries to quickly and efficiently detect whether raw materials or finished products contain Stainless steel, iron, copper, lead and other metal impurities, and the optional automatic rejection system will separate the products containing metal foreign matter, thus providing a strong guarantee for the safety of the product.
The working principle of the metal detector is very simple, a central transmitting coil and two equal receiving coils, all three coils are housed in a probe. The oscillator emits a high-frequency magnetic field through the transmitter coil in the middle, which is connected to the two receiver coils, but with opposite polarities. When the magnetic field is not disturbed by the outside world, the voltage output signals generated by them cancel each other out. Once the metal impurities enter the magnetic field area, the signals output by the two output coils cannot be canceled, prompting the alarm system to issue an audible and visual alarm, indicating that the presence of metal is detected.