METAL-DETECTING METHOD AND APPARATUS

摘要

PROBLEM TO BE SOLVED: To solve the problem that accuracy for detecting mixed metal foreign objects varies due to the difference in the size of a non-metal product. SOLUTION: The metal-detecting apparatus 1 comprises a belt conveyor 3, a detection frame 4 that incorporates a metal detection coil for magnetically detecting metal foreign objects that are mixed into a target 8 to be detected, and a dimension-measuring sensor 6 that is a dimension-measuring means 5 for measuring height dimensions on the belt conveyor 3 of the target 8 to be detected at the upstream side. The metal-detecting apparatus also has an elevation means 7 for elevating the detection frame 4 so that the upper and lower gaps between the detection frame 4 and the target 8 to be detected become nearly equal when the target 8 to be detected passes the detection frame 4.