| 摘要 |
<p>The drill for making test holes during mining operations employs a sleeve (2) with a drive block (3) inside, between front and rear torsion blocks (4) and/or an elastic layer (5) between the drive block and the sleeve. Hand grips extend sideways each side of the sleeve. This arrangement is used to establish the torque required for the drilling tool to be attached to the drive head (6) on the drive block. An indicator needle can be mounted on a carriage (7) which travels on a threaded spindle (8) parallel with the axis of the sleeve, which can trace a mark on a recording sheet (10) mounted in an opening in the sleeve. In an alternative design, a pointer can be externally mounted, which moves over a scale marked on the outside of the sleeve.</p> |
