| 摘要 |
PURPOSE:To prevent dislodging of a part to be detected owing to the difference of coefficients of thermal expansion by mixing a granular magnetic material with a binder, casting the mixture into the hollow hole part of a member of a nonmagnetic material which performs periodic movement, setting said material and using this as the part to be detected. CONSTITUTION:A part 3 to be detected is buried on the outside circumferential surface of a rotating member 1. The part 3 is formed by packing and setting magnetic material particles 6 mixed with a binder 5 in a recessed part 4 pierced on the outside circumferential surface of the member 1. However, a bulging part is formed on the side face of the part 4 in order to prevent the dislodging of the part 3 surely despite the occurrence of peeling between the part to be detected and the inside circumferential wall of the part 4. An electromagnetic sensor 7 is mounted to a fixing member 8 in such a way as to face a part of the locus of the periodic movement of the part 3. It is possible to detect temp. if particles of tem. sensitive ferrite are used for the particles 6. |
