| 摘要 |
PURPOSE:To secure a damping characteristic approximate to an ideal, by using this device for a supporting leg available in record players, etc., and detecting relative displacement relationships between a body and a leg seat as well as controlling a relative position between both members with electromagnetic force. CONSTITUTION:A coil 7 is secured to a body 1 via a bobbin 6, and each of yokes 9 and 10 making up a magnet 8 and its magnetic path 1 is secured to a leg seat 4 while the coil 7 is interlinked with the magnetic field formed by these yokes 9 and 10 and constituted so as to move around inside the magnetic path. A photointerrupter 12 varies its output current according to the quantity of light received from a light source 13 while the output current varies with change in the light receiving quantity by the vertical motion position of a shutter 14 secured to the leg seat 4 via the yoke 10. This output current is added to the coil 7 via a power amplifier 19, etc., and controlled so as to keep the relative position between the body 1 and the leg seat constant. |
