| 摘要 |
<p>A bidirectional motorised gearing (20,19) controls the rotation of the boom support (6) when the boom (9) is raised towards the overhead wire (f). The collector shoe (25) of flexible or rigid material is jointed about an axis (26) with a shock absorber (27). The boom is raised and lowered by a pneumatic jack (17) and maintained in contact by a coil spring (12). The gear wheel (20) slides into mesh under the action of a fork (23) at the end of the shaft of an auxiliary jack (24). Rotation of the boom about a vertical axis is controlled by the motor so as to ensure that contact is re-established with the overhead wire. The collector shoe is oriented, by means of a remotely controlled aiming sight and retractable adjustment, in line with the wire regardless of the angular position of the boom w.r.t. the vehicle.</p> |
