| 摘要 |
<p>For mining work the apparatus has a main frame (10) with heavy side walls (12) and (14) joined by transverse braces (18) to form a box-like configuration. The frame (10) is carried on endless tracks and acts as a counterweight to the forces developed at the excavating buckets (74). These are carried on a boom (36) swingable about vertical pivot (24) and horizontal pivot (80) by rams (48) and (50). The buckets (74) have hinge pins 68 whose enlarged ends engage sprockets (58) and (60) for supporting and driving the bucket chain. The buckets have replaceable excavating teeth (not shown).</p> |
