| 摘要 |
<p>The invention relates to a vibrator specifically for a hearing aid device of the bone conduction type, i.e. a hearing aid device by which the sound information is mechanically transmitted via the skull bone directly to the inner ear of a person with impaired hearing. The vibrator comprises a coil which is divided into two coil halves (1a, 1b) for generating a dynamic magnetic field and a permanent magnet (3) for generating a static magnetic field. The permanent magnet (3) is radially magnetized and arranged in such a way that the static and dynamic magnetic fields are coinciding in the air gaps (6a, 6b) formed between the coil and magnet arrangement and the casing (4), whereby the vibrator provides an axial force (7). Preferably, the entire coil and magnet arrangement is enclosed in a casing (4) which forms a part of the magnetic circuit and protects the vibrator and reduces magnetic leakage.</p> |
