| 摘要 |
<p>Carriage (6) has a main frame (13) cooperating with the ladder and a secondary frame (14) which is free in translation relatively to the main frame between a high (A) and a low position (B). The secondary frame is attached to one end of the cable (12) so that the carriage is maintained in the high position by the cable tension until when the main frame reaches the lower position.</p> |
