Method and apparatus for verifying the presence of ferromagnetic components in an assembly

摘要

An apparatus is provided for verifying the presence or, conversely, determining that one or more ferromagnetic components is missing from an inspected assembly. The apparatus includes a scanning head that creates a magnetic field. An assembly having one or more ferromagnetic components is located in a predetermined position relative to the magnetic field. A load cell subassembly of the scanning head produces an output signal representative of its movement, which movement is proportional to the number and location of ferromagnetic components in the assembly. The apparatus further includes a processing network that processes the output signal in order to provide an indication as to whether or not one or more ferromagnetic components is missing from the assembly. In conjunction with such processing, previously obtained reference values are compared with the determined magnitude obtained by processing the output signal from the load cell subassembly.