| 摘要 |
PROBLEM TO BE SOLVED: To prevent the vibration of the whole of a ferrite bead even though the frequency change of a magnetic flux approximates to the resonant frequency of the ferrite bead. SOLUTION: As shown in Fig. (A), the ferrite bead so has a doughnut-form sectional shape and so has a three-dimensional shape wherein either one of its inner diameter D2 and its outer diameter D1 changes continuously in its axial direction that its mean diameter 12d also changes continuously from its upper end surface 12b to its lower end surface 12c. Therefore, even when a magnetic-flux change is generated by the current flowing in a lead wire inserted into its through hole 12a, its mean diameter and its sectional area change continuously in all its axial positions. Thereby, even though the frequency of the magnetic-flux change approximates to the resonant frequency determined by the structure and material of the ferrite bead, the whole of the ferrite bead so generates no vibration determined by the resonant frequency as to be to able to prevent its destruction caused by the resonance of the ferrite bead. COPYRIGHT: (C)2006,JPO&NCIPI
|
