| 摘要 |
PURPOSE:To measure and display variation of the total quantity of foreign matter particles and the quantity of large particles, by converting the force for attracting the foreign matter particles by a magnet, to a distortion. CONSTITUTION:In case of detecting a magnetic material, for instance, an iron particle, the iron particle 12 contained in oil is caught by attracting force of a magnet 5 and adheres to the surface of a thin plate 4. Subsequently, a distortion is generated in the thin plate 4 due to attracting force of the iron particle by the magnet 5. This distortion and weight of the iron particle are in a proportional relation. That is, the distortion of the thin plate 4 is detected by a strain gauge 6, resistance variation of the strain gauge 6 is measured by a Wheatstone bridge 9, this electric signal is amplified by an amplifier 10, and the total quantity of the iron particle and a size of the iron particle 12 are displayed 11. In such a way, variation of the total quantity of a foreign matter particle and the quantity of a foreign matter large particle can be measured and displayed. |
