| 摘要 |
A swinging-arm device (5) for an optical disk player comprises a swinging arm (16), which near one end (17) carries an optical scanning unit (6) and which is electromagnetically pivoted by means of coils (27, 28) arranged on the swinging arm and a permanent magnetic stator (29, 30, 49-52, 54) arranged on a stationary mounting of the device. The centre of mass (Z) of the pivotal assembly comprising, inter alia the swinging arm and the optical scanning unit is disposed on the pivotal axis and the two coils are disposed diametrically opposite one another on opposite sides of the pivotal axis and exert equal pivotal forces which act in one plane which is perpendicular to the pivotal axis and which extends through the centre of mass. The centre of mass is disposed midway between two ball-bearings (20, 21). |
