| 摘要 |
PURPOSE:To improve the efficiency and to obtain a fixed driving force regardless of a movement of the magnet by providing a pair of movable magnets opposite to a coil wound around a yoke and by placing magnetic elements at both ends of the yoke. CONSTITUTION:The rollers 6, 7 installed on the moving body 4 run along a pair of guide rails 5a, 5b. A pair of magnets 8a, 8b is attached to the lower part of the moving body 4 on providing gaps between the magnets and the coil wound around the yoke 10, and the magnetic elements 12, 13 are placed at both ends of the yoke 10. When the coil 9 is energized, a force acts between the magnets and the coil, the magnets are horizontally moved and the tone arm 1 performs a tracking in a horizontal plane. Since two magnets are used, a greater driving force can be obtained even though less current flows in the coil, the efficiency can be improved. Moreover since the two attractions generated between the magnets 8a, 8b and the yoke 10 are the same in magnitude and reverse in direction, the two are canceled and the action is stabilized. |
