摘要 |
<p>The break shield, hinged to the prop-supported cap on the backfilling side, and lemniscate gearing interposed between floor sill and cap, are incorporated in a shield block, esp. for use in extracting thick deposits by the disc or drawing-out process, in mining. The break shield (26) is divided into hinged sections, and its lower part (30) has at least one guide-rod (31) hinged to it and coupled to the lemniscate gear. The guide-rod may be bent or curved upwards. The bottom shield part can also have a telescopic component (36) fitted to it, for hydraulically extending downwards, pref. with a support roller (37), or similar at the bottom end.</p> |