To provide an impeder core which can make a welding efficiency stable.
The impeder core 9 comprises seven ferrite cores 21. Each ferrite core 21 is rodlike and has a dodecagonal cross-section perpendicular to its longitudinal direction. The seven ferrite cores 21 are held in an impeder case 11 in a state of being inserted into the impeder case 11. The ferrite cores 21 are bunched so that each ferrite core 21 touches another ferrite core 21 on at least two lateral sides. When the seven ferrite cores 21 are bunched, spaces 23 which extend in the longitudinal direction of the ferrite cores 21 are formed by and among the lateral sides of respective ferrite cores 21 because of their dodecagonal cross-section perpendicular to their longitudinal direction.
COPYRIGHT: (C)2007,JPO&INPIT
ITO HIROAKI
Shiro Terasaki
Hiroaki Aoki