| 摘要 |
An extendable boom assembly is mounted on a platform or a base for longitudinally pivotally moving a drill rod between a rod rack and a drill rig in a position in alignment with the drill string axis regardless of whether the drilling direction is vertical or is angularly positioned relative to the vertical direction. The boom assembly is mounted for pivotal movement with the track assembly and transverse movement relative thereto, the track assembly being mounted on a drill rig platform. The upper end of the boom assembly mounts a jaw assembly for releaseably gripping a drill rod, the jaw assembly being mounted for limited pivotal movement about a horizontal axis and is of a design not requiring the rods being in a particular spaced relationship relative to one another. The gripping assembly jaws and the limited pivotal movement results in the rod to be transferred being pivoted to a position parallel to the main boom arm central axis as the rod is being clampingly engaged and moved away from the rod stack. The controls are located at a location away from the path of movement of the clamped drill rod. |
