Self-retaining roof bolt
AssigneeChevron Research Company
InventorWilliam G. Toland
Life of this patent
Estimating the term…
Abstract
A self-retaining roof bolt comprising an elongated U-shaped member having a pair of spaced legs which support a flat plate fitted over the U-shaped member and are held under transverse tension at ambient temperature by a grouting which becomes malleable at elevated temperatures. The roof bolt is installed in a roof hole by momentarily heating the leg sections, which causes the grouting to soften, releasing the tension on the legs and allowing them to separate and wedge against the roof hole walls. Thus, the bolt retains itself in the roof hole while the grouting cools. Upon cooling, the grouting re-solidifies, firmly securing the bolt.
Claims9
A self-retaining roof bolt comprising:
- a. an elongated U-shaped member having a pair of spaced leg sections depending from the connection portion of said U-shaped member, said leg sections being formed to support a flat plate fitted over said U-shaped member;
- b. a grouting coated on said U-shaped member to maintain said leg sections under transverse tension at ambient temperature, said grouting being malleable at elevated temperatures;
- c. a flat plate having an opening therein positioned over said U-shaped member and supported by said leg sections, said opening being large enough to permit said leg sections to move transversely on release of said transverse tension a sufficient amount to maintain said U-shaped member in place in a roof hole;
- and
- d. a gasket abutting said flat plate member and in sealing engagement with the lower portion of said U-shaped member to prevent flow of said coating below said plate at elevated temperature.
Dependencies are inferred from the claim text.