| 摘要 |
<p>An access trolley for use with an overhead power line, comprises: (i) a cradle (2) for an operator; (ii) one or more wheels (30) attached to the cradle for supporting the cradle on the line, the or each wheel being located above the cradle to allow the cradle to hang below the line, and having a pneumatic tyre (26, 28) for distributing the weight of the trolley on the line; and (iii) means (18) for driving the trolley along the line. Preferably the tyre of the or each wheel is inflated to a relatively low pressure, for example not more than 200 kPa to increase the linear distance and in order that the maximum pressure that the tyres exert on the line due to the weight of the trolley and load is not more than 20 kPa. By such means, damage to any optical line that may be wrapped along the line, due to the weight of the trolley, will be prevented or reduced.</p> |
