| 摘要 |
<p>A rotary actuator is provided for use as part of a servomechanism for positioning one or more data recording and/or recovering heads over selectable radii on one or more rotating data storage discs, the actuator 10 comprising a head arm 24 pivoted to rotate with a shaft 20 held between bearings 18 32 in a yoke 12, the actuator 10 being characterised by one of the bearings 18 being a composite bearing allowing both axial and rotational movement of the shaft 20 without play and by the other bearing 32 being a rotary bearing, the two bearings 18, 32, co-operating to fix the axial position of the shaft 20 whilst allowing free rotation and axial movement due to dimensional changes whenever the axial force exceeds a predetermined limit, thereby avoiding rotary bearing binding or undue play attendant upon prior art designs.</p> |
