| 摘要 |
PURPOSE:To utilize a magnetic circuit for a temperature monitor by providing an electric circuit as a variable inductance element by utilizing the magnetic circuit for varying a magnetic resistance by moving a magnetic unit by the deformation of an SMA with the element for varying the coupling degree of a coil with a core by the deformation of an SMA wire. CONSTITUTION:When an SMA5 is formed at an ambient temperature in the shape as shown in Fig. (a) and when the SMA5 is deformed at 40 deg.C or higher as shown in Fig. (b) due to the opening of the opposed parts of the both ends of a core 3, the magnetic resistance of the core 3 largely reduces in case of Fig. (a) as compared with the case of Fig. (b). Accordingly, a magnetic circuit which can vary its magnetic resistance by the temperature can be provided. When the magnetic circuit has the primary and secondary winding 1, 2, the electromagnetic coupling degree of the windings can be largely varied to be provided as a variable mutual inductance element. The inductance of the coil may be altered by changing the relative position of the magnetic unit and the coil without varying the magnetic resistance. An SMA wire is used as a coil, and a variable inductance element which alters the magnetic resistance of the magnetic circuit by the deformation may be provided. |
