| 摘要 |
A mineral cutting pick of the type adapted to be traversed relative to a mineral face and having a leading cutting edge and an outer cutting edge incorporated in a hard metal insert mounted in a rebate formed by a pair of seating surfaces at the end of a pick body remote from a shank for use in securing in a socket of a chain or drum or the like, wherein at least one end of the leading cutting edge adjacent the outer cutting edge has negative rake with respect to the shank, and the leading cutting edge is defined by surfaces the angle between which increases from the position at which it will make foremost contact with the mineral face to the end of the leading cutting edge adjacent the outer cutting edge, whereby a sharper angle for the leading cutting edge is provided where it will attack the mineral face and a blunter angle is provided towards the end adjacent the outer cutting edge to afford greater strength as the insert decreases in transverse width towards the outer cutting edge.
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