In this paper, a polar coordinate drill-rod lifter was developed to strictly control drill rod in order to precisely locate the rod.

The long box assembly comprises a long box body, channel steel, a lifter, a cam mechanism, a pull and push plate, a supporting rod, etc.

As the camshaft turns, the CAM lobe comes around under the valve lifter. This raises the lifter, which in turn pushes upward on the push rod.