| 摘要 |
<p>The coal pick for a rotary cutting head has a block (28) mounted on a stem (20) and a tungsten carbide tip (27) is mounted on the block, projecting forwards. The stem is made of angle section metal, and clipped onto the cutting head (40). The rear part of the stem is cut away (24) for the clip (42). Thus the stem is V-shaped, and its widest part is the same size as, or larger than, the width of the block (28). The block is inset into the head (40) and is stepped, with a lug (48) fitting into a corresponding groove in the block. In an alternative design, this lug is sloping sided. Alternative designs include blocks (28) which are fitted with dowels or securing screws.</p> |
