| 摘要 |
PROBLEM TO BE SOLVED: To solve the problem in a conventional magnetic circuit for a speaker, that a price is high since magnets with high magnetic characteristics including expensive rare earth, etc. have been used in order to obtain a large magnetic flux density.SOLUTION: The present invention includes: a first plate 2A and a yoke 2B that are joined with magnets 11; and a magnetic gap 4. The magnets 11 includes: a first magnet part 11A; and a second magnet part 11B with magnetic characteristics lower than those of the first magnet part 11A. The first magnet part 11A is arranged close to the magnetic gap 4 and the second magnet part 11B is arranged at a position further separated from the magnetic gap 4 compared with the first magnet part 11A. The first magnet part 11A and the second magnet part 11B are connected in parallel. By the configuration, the contribution level of the second magnet part 11B becomes smaller. Thus, it is adequate to lower the magnetic characteristics of the second magnet part 11B, and an inexpensive magnet can be used for the second magnet part 11B. |
