| 摘要 |
<p>A continuous crawler (10) comprises two platforms (12) and each platform (12) comprising two sliding carriages (14). Each sliding carriage (14) comprises engaging means (16) for engaging a surface (18) below the continuous crawler (10) and each sliding carriage (14) is arranged to slide forwards and backwards relative to their respective platform (12). Driving means (20) is provided for driving the sliding carriages (14) backwards and forwards and control means (22) is provided to control the engaging means (16) and driving means (20). The control means (22) is arranged to drive one sliding carriage (14) on each platform (12) backwards relative to the respective platform (12) while the engaging means (16) on these sliding carriages (14) are engaging the surface (18) and simultaneously drive the other sliding carriage (14) on each platform (12) forwards relative to the respective platform (12) while the engaging means (16) on these sliding carriages (14) are not engaging the surface (18). Once the sliding carriages (14) reach the full extent of their movement then their roles are reversed, with a short period of overlap while all of the sliding carriages (14) have their engaging means (16) engaging the surface (14).</p> |
