| 摘要 |
<p>The adjustable mine support can be used behind a scraper conveyor at the coal face. It has a roof member supported by a swinging arm system above a floor member (12) by a telescopic piston and cylinder, the bottom (10) of the cylinder being rounded, with spigots (19) projecting sideways to act as hinge pins. These spigots fit into recesses (16) in side plates (11) forming part of the floor member. Each recess consists of a slot (18), sloping downwards, terminating in a larger recess whose base slopes at an angle to the floor. The slot is then closed by two keys (30). The upper key (20) has a lug (29) with a sloping face (27) against which locks the sloping tip of the other key (26). The end of the lug is shaped to fit partly around the spigot.</p> |
