MACHINE FOR DRIVING HOLES IN THE GROUND

摘要

MACHINE FOR DRIVING HOLES IN THE GROUND A machine for driving holes in the ground comprises a cylindrical housing, a hammer disposed inside the housing, and an air distribution mechanism. Longitudinal recesses and projections are provided on a portion of the outer surface of the housing at its head end section. The diameter of the cylindrical part of the housing is greater than the diameter of a circle described about the bottoms of the recesses and smaller than the diameter of a circle described about the tops of the projections.