| 摘要 |
<p>1448527 Variable capacitors PHILIPS ELECTRONIC & ASSOCIATED INDUSTRIES Ltd 19 Dec 1974 [22 Dec 1973] 54895/74 Heading H1M A variable capacitor comprises an endless belt 15 movable around drums 7, 11 and having a metal coating on its inside surface to provide one of the electrodes, the other being constituted by the drum 7 or a conductive portion of its surface, there being interposed dielectric material, the belt being formed from metal-coated plastics strip by securing an end A thereof to an intermediate portion B, leaving a tail portion to provide a flexible connection to the belt. As shown in Fig. 2, separate electrodes 17<SP>1</SP> with lead portions 1711 are supported on the belt, and rotation of drum 5 moves portions 17<SP>1</SP> into or out of capacitive relationship with the second electrode. The dielectric may be polyparaxylylene deposited on the inside surface of the belt or on drum 5. The axis of drum 11 is adjustable whereby springs 23 can act to keep the belt taut.</p> |
