| 摘要 |
<p>A travelling gantry has a chassis which is mounted on wheels to travel along rails, with a rotary connection on top on which is mounted the structure from which extends the jib of a crane. The chassis is supported on two bogies for each rail. Each bogie is supported on a pair of leading wheels and on a pair of trailing wheels. Between the leading and trailing sets is a pedestal which can be lowered to support the structure, instead of the wheels. Each bogie can swing about a vertical axis and the wheel sets on one rail are connected to the wheel sets on the other rail by bridging members between the bogies. An alignment monitoring system for the wheels is used.</p> |
