| 摘要 |
<p>An extension arm (30) has a first section (58,60) to move on bearings on a side-thrust frame and a second section (70), which swivels on bearings on a vertical axis on the first section and on which there is placed a means (76) of bearing a load, operated by a hydraulic lifting cylinder (72). A swiveling device (66) for the second section operates on bearings on the first section.</p> |
