Anchoring screw with double heads and triple threads of different depths of thread

Abstract

An anchoring screw with triple threads of different depths of thread especially useful for coupling with a construction hole on a cement wall (or other construction boards and panels) includes a first bolt section, a tool driven section and a second bolt section. The second bolt section has a first screw thread, a second screw thread and a third screw thread of different depths of thread formed on the outer surface that are spaced from one another at 120 degrees. Thus, the screw threads can gather extruded cement debris when the screw is fastened into the construction hole to produce a stronger fastening effect. As there is no expansion incurred, the wall or board does not crack. Therefore, the interval between the construction holes may be shortened, and the number of construction holes may be increased in a given unit area. The anchoring screw of the invention also may be removed easily and conveniently to facilitate construction.

Dependencies are inferred from the claim text.