| 摘要 |
<p>On top of the rotor arm are three metallised ribs (8, 9, 10) which are in the shape of concentric arcs of different lengths. The lengths of the arcs decrease as a function of the distance away from the centre of the rotor arm. The inner rib (8) makes an angle of about 150 [deg.] and the outer rib (10) an angle of 70 [deg.]. The ribs (8, 9, 10) are moulded when the rotor arm is fabricated and are made from a plastic material. The rib (9) is covered with a metallic conducting deposit. The ribs are approximately symmetrical w.r.t. the common axis perpendicular to the centre line of the main contact (6a). The outer rib (10) acts as a screen between the central zone of the rib (9) and the distributor terminals (7a, 7b, 7c). The inner rib (8) also forms a screen between the conducting path formed by the main contact (6a) and the median rib (9).</p> |
