| 摘要 |
<p>An operating element rotatable about an axis (X-X) perpendicular to the base (34) carries contacts (19a, 19b, 19c) which connect with certain components on the printed circuit (36, 60, 62), so that the circuit is selectively controlled, and the load supplied with corresponding ratings of electric energy. The connection between the operating element and the contacts is effected via a resistor section in the form of circular strips. The variable resistance thus created constitutes a relatively long track along which the associated contact can be moved. The accuracy of regulation is thereby improved. The simplicity of working enables a compact construction to be realised.</p> |
