| 摘要 |
<p>Overhead access platform comprises a wheeled base 10, an extendable mast 16 comprising at least two sections 17, 18 connected together for relative sliding movement, a lower section 17 of the mast being mounted on the base 10, a platform 26 attached to an upper section 18 and a counterweight 31 assembly. Each section may comprise a pair of rails 20, 22 with rungs 21, 23 therebetween, at least one of the rails of the lower section may be hollow to receive the counterweight 31 assembly. A flexible tension member 29 which may be a metal cable or chain, with a guide such as a pulley, interconnects the second section to the counterweight. The second section 18 of the mast is narrower than the first section 17, there may be at least one intermediate section being slidably arranged with respect to the existing sections, corresponding counterweight assemblies may be provided between the sections. The base may have outriggers 13. Releasable pawls, dogs, pins or rung locks 32 may be arranged between the sections. Struts (35, figure 6) may be provided between the base and the rails and rungs (37) may extend therebetween. The work platform may be provided with a handrail 27 and gate 28.</p> |
