Yieldable roof support system
AssigneeDyckerhoff & Widmann AG of Munich
InventorsKhaled Shawwaf, Johann Wlodkowki, Thomas Herbst, Ray Brandon
Life of this patent
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Abstract
A support includes a base member having an open end and a hollow interior, a forcing member having an end extending through the open end of the base member into the hollow interior thereof and having threads thereon and a mandrel or sliding nut capable of engaging the threads of the forcing member at an adjustable position and providing an interfering relationship between the base and forcing members as a compressive load is applied thereto. The support is particularly adapted for use in supporting the roof of a mine.
Claims29
A support, comprising:
- a base member having an open end and an inner wall of a first cross-sectional size defining a hollow interior;
- a forcing member having an end extending through the open end of the base member into the hollow interior thereof and having threads thereon;
- and
- a further member having a portion of a second cross-sectional size larger than the first cross-sectional size and capable of engaging the threads of the forcing member at an adjustable position wherein the portion is movable into the interior of the base member for expanding the inner wall outwardly at a point of contact of the portion with the inner wall of the base member as a compressive load is applied to the forcing member.
A roof support for a mine, comprising:
- a pipe having first and second ends and a wall defining a channel therethrough of circular cross-section having a substantially constant diameter over its length;
- a bar having first and second ends and threads about an outer periphery thereof;
- a mandrel having a threaded bore therethrough in engagement with the threads on the bar whereby the mandrel may be positioned at a desired point on the bar by turning the mandrel relative to the bar, the mandrel further including an outer surface of first diameter smaller than the substantially constant diameter at a first end thereof and of second diameter larger than the substantially constant diameter at a second end thereof opposite the first end;
- wherein the first end of the bar extends through the first end of the pipe and the mandrel is disposed at least partially within the pipe channel such that the outer surface thereof is in interfering contact with the walls of the pipe and wherein the second end of the mandrel is moved into the pipe and the pipe wall is deformed radially outwardly at a point of contact of the second end of the mandrel with the pipe wall when a load of a certain magnitude is applied to the bar;
- and
- top and bottom plates disposed on the second ends of the bar and pipe, respectively, and adapted to engage a roof and a floor, respectively, of a mine.
A roof support for a mine, comprising:
- a support structure having a support surface and an aperture therethrough;
- a bar having first and second ends and a projection about an outer periphery thereof, the projection having a first shear strength;
- a sliding nut having a bore therethrough and having a portion in engagement with the projection on the bar whereby the portion of the sliding nut has a second shear strength greater than the first shear strength;
- wherein the first end of the bar extends into the aperture and the sliding nut is disposed in contact with the support surface of the support structure;
- and
- top and bottom plates disposed on the second ends of the bar and support structure, respectively, and adapted to engage a roof and a floor, respectively, of a mine whereby loads applied to the top and bottom plates place the bar and support structure in compression.
Dependencies are inferred from the claim text.