摘要 |
Improved automatic surface-treating apparatus of the type supported by and traversing a horizontal surface unattended. The apparatus includes mobility members for movement in a principal direction and side-step members having rotational axes a given distance above the surface. Each side-step member has a first sector with a far periphery spaced from its axis by more than the given distance, and a second sector with a near periphery spaced from its axis by less than the given distance. This arrangement allows a single rotation of the side-step members to accurately lift and move the apparatus laterally through a predetermined distance, to a new surface-treatment path. |