| 摘要 |
PROBLEM TO BE SOLVED: To detect a matter, accurately, from a small metal, solid foreign matter, and air bubble, regardless of whether the matter is a magnetic matter or non-magnetic matter, with a simple and inexpensive structure.SOLUTION: A foreign matter detection device comprises: magnetic field generation means for generating a magnetic field; magnetic force change detection means 14 disposed in the magnetic field and detecting change of the magnetic force; movement means for moving an object to be inspected to an adjacent place of the magnetic force change detection means 14 from a distant place, and moving it to the distant place from the adjacent place; and means for detecting a metal, solid foreign matter and air bubble, based on magnetic field variation, after determining the magnetic field variation based on a signal detected by the magnetic force change detection means 14. |
