| 摘要 |
PURPOSE:To simplify the replacement of a stylus by realizing simple and lightweight structure and high power generating efficiency by extracting a signal of electromotive force generated through the movement of moving coils according to vibration of a cantilever. CONSTITUTION:Since magnetic gaps between opposite magnetic-pole parts of magnets 11a and 11b and foot part 9a1 of magnetic core 9a are smaller than those of foot part 9a2 when cantilever 2 moves upward, magnetic flux passing through coil 8a1 becomes more than that passing through coil 8a2 and a current is outputted in a fixed direction corresponding to a difference in magnetic flux. On the other hand, since the magnetic gap between the opposite magnetic parts and foot part 9a2 becomes smaller than those of foot part 9a1 when cantilever 2 moves downward, the magnetic flux passing through coil 9a2 becomes more than that of coil 8a1 and a current is outputted in the opposite direction to the fixed direction corresponding to this magnetic-flux direction. Then, since coils deviate from the center axis of the cantilever by a fixed distance, needed magnetic flux distribution is small and simple and lightweight structure and high power generating efficiency are realized, so that the replacement of a stylus will be simplified. |
