Patent CA1039986A successfully refreshed from Google Patents.
CA1039986A
Expired / Lapsed
CA
⏱️ 0.0 years remaining
Rock bolt assembly
Assignee: NATIONAL HARDWARE SPECIALTIES Ltd
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Filing: 1976-06-21
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Granted: 1978-10-10
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Expires: 1996-06-21
Abstract
Abstract ABSTRACT An expansible shell formed of a deformable material and rock bolt assembly incorporating said shell is described. The shell comprises a one-piece casting formed of zinc, zinc alloy, aluminum, iron or plastics by die or gravity casting or by injection moulding. Each shell consists of a plurality of outwardly diverging leaves each with a transversely convex curved outer rock engaging face for defining a substantially cylindrical external surface when the shell is compressed to its operative shape. A planar face is formed on the inner side of each leaf inclined at a small angle of about 8° to the longitudinal centerline of the outer convex face whereby the leaf has a thin inner end and a thick outer end. The shell inner ends each have a thin, resilient arm formed as an inner extension which interconnect to form a central bail-like structure. In a preferred embodiment, the shell is adapted to fit over and engage a nut having a plurality of tapered planar faces corresponding with the planar inner faces of the leaves for expanding the leaves radially upon longitudinal axial movement of the nut relative to the shell. The shell and rock bolt assembly of the invention provide a simple structural combination wherein the shells can be nested for storage and shipment, easily adapted for use, and the rock bolt assembly readily installed to provide improved surface area contact with a drill hole wall and improved resistance to sleeve slippage.
Inventors
- 👤 Donald B. Haslam
- 👤 John W. Reynolds
Bibliographic Details
Application Number
—
Jurisdiction
CA
Data Source
google_patents
Last Synchronized
2026-10-26 18:34
CPC Classifications
E; E21; E21D; E21D21/00; E21D21/008; F; F16; F16B; F16B13/00; F16B13/04; F16B13/06; F16B13/063; F16B13/066
Claims Analysis
Total Claims: 26
Claim 1
Independent Claim
165 words
A shell for use in a bolt assembly for anchoring in a drill hole, comprising: a one-piece casting having at least six symmetrically disposed outwardly diverging deformable leaves each with a substantially transversely convex curved outer rock engaging face, said leaves collectively capable of defining a substantially cylindrical external surface having a large area of contact, and a planar face formed on the inner side of each leaf, said planar inner face inclined at a small angle to the longitudinal axis of the corresponding outer face, said angle opening outwardly from the leaf inner end towards the leaf outer end whereby said leaf has a thin inner end and a thicker outer end, and a plurality of thin, resilient arms formed as inner extensions of the thin inner end of said leaves interconnected to form a central breakable bail-like structure, said casting formed of a material deformable by the rock in which it is anchored whereby rock projections can be embedded in the shell leaves.
Claim 2
Dependent Claim
165 words
A shell for use in a bolt assembly for anchoring in a drill hole, comprising: a one-piece casting having at least six symmetrically disposed outwardly diverging deformable leaves each with a substantially transversely convex curved outer rock engaging face, said leaves collectively capable of defining a substantially cylindrical external surface having a large area of contact, and a planar face formed on the inner side of each leaf, said planar inner face inclined at a small angle to the longitudinal axis of the corresponding outer face, said angle opening outwardly from the leaf inner end towards the leaf outer end whereby said leaf has a thin inner end and a thicker outer end, and a plurality of thin, resilient arms formed as inner extensions of the thin inner end of said leaves interconnected to form a central breakable bail-like structure, said casting formed of a material deformable by the rock in which it is anchored whereby rock projections can be embedded in the shell leaves.
Claim 3
Dependent Claim
32 words
A shell as claimed in Claim 1, wherein said casting has a plurality of outwardly diverging leaves symmetrically disposed about a central bail-like structure whereby said shells can be stacked by nesting.
Claim 4
Dependent Claim
31 words
A shell as claimed in Claim 1, wherein said one-piece casting is formed of zinc, zinc alloy, iron or aluminum by gravity or die casting or of plastics by injection moulding.
Claim 5
Dependent Claim
39 words
A shell as claimed in Claim 1, 2 or 3, wherein said thin resilient arms are of reduced width relative to the leaves whereby radial openings are defined between adjacent resilient arms about the centre of the bail-like structure.
Claim 6
Dependent Claim
18 words
A shell as claimed in Claim 1, 2 or 3, wherein the small angle is about 8 degrees.
Claim 7
Dependent Claim
18 words
A shell as claimed in Claim 1, 2 or 3, wherein the central bail-like structure is cylindrically shaped.
Claim 8
Dependent Claim
44 words
A shell as claimed in Claim 1, 2 or 3, wherein the opposite side edges of the leaves are bevelled parallel with radii of the cylindrical surface definable by the leaves whereby the leaves are spaced from each other upon closure of the shell.
Claim 9
Dependent Claim
30 words
A shell as claimed in Claim 1, 2 or 3, wherein the planar inner face of each leaf has a concave central recess formed therein at the thicker outer end.
Claim 10
Dependent Claim
35 words
A shell as claimed in Claim 1, 2 or 3, wherein each leaf outer face has a flat central portion extending the length thereof providing two wide-area control zones on each said leaf outer face.
Claim 11
Dependent Claim
35 words
A shell as claimed in Claim 1, 2 or 3, wherein each leaf outer face has a concave central portion extending the length thereof providing two wide-area contact zones on each said leaf outer face.
Claim 12
Dependent Claim
275 words
A rock bolt assembly for anchoring in a drill hole comprising, in combination: a shell comprising a one-piece casting having at least six symmmetrically disposed outwardly diverging deformable leaves each with a substantially transversely convex curved outer, rock-engaging face, said leaves collectively capable of defining a substantially cylindrical external surface having a large area of contact, and a planar face for receiving expansion means formed on the inner side of each leaf, said face inclined at a small angle to the longitudinal axis of the corresponding outer face, said angle opening outwardly from the leaf inner end towards the leaf outer end whereby said leaf has a thin inner end and a thicker outer end, and a plurality of thin, resilient arms formed as inner extensions of the thin inner end of said leaves interconnected to form a central breakable bail-like structure; expansion means having planar faces corresponding with the planar inner faces of the leaves and oppositely inclined at the same small angle to its principal axis adapted to fit within said shell, said expansion means operatively connected to a bolt; means for moving said expansion means longitudinally relative to said shell whereby said shell leaves expand by movement of the shell inclined planar faces on said oppositely inclined planar faces of said expansion means to bring the shell convex outer faces into engagement with said drill hole wall while retaining the shell planar inner faces in large area contact with the planar faces of the expansion means, said shell casting formed of a material deformable by the rock in which it is anchored whereby rock projections can be embedded in the shell leaves.
Claim 13
Dependent Claim
275 words
A rock bolt assembly for anchoring in a drill hole comprising, in combination: a shell comprising a one-piece casting having at least six symmmetrically disposed outwardly diverging deformable leaves each with a substantially transversely convex curved outer, rock-engaging face, said leaves collectively capable of defining a substantially cylindrical external surface having a large area of contact, and a planar face for receiving expansion means formed on the inner side of each leaf, said face inclined at a small angle to the longitudinal axis of the corresponding outer face, said angle opening outwardly from the leaf inner end towards the leaf outer end whereby said leaf has a thin inner end and a thicker outer end, and a plurality of thin, resilient arms formed as inner extensions of the thin inner end of said leaves interconnected to form a central breakable bail-like structure; expansion means having planar faces corresponding with the planar inner faces of the leaves and oppositely inclined at the same small angle to its principal axis adapted to fit within said shell, said expansion means operatively connected to a bolt; means for moving said expansion means longitudinally relative to said shell whereby said shell leaves expand by movement of the shell inclined planar faces on said oppositely inclined planar faces of said expansion means to bring the shell convex outer faces into engagement with said drill hole wall while retaining the shell planar inner faces in large area contact with the planar faces of the expansion means, said shell casting formed of a material deformable by the rock in which it is anchored whereby rock projections can be embedded in the shell leaves.
Claim 14
Dependent Claim
44 words
A rock bolt assembly as claimed in Claim 11, wherein said expansion means comprises a nut threaded onto said bolt for longitudinal movement thereon, said nut having planar faces formed symmetrically thereon corresponding to planar inner faces of the leaves for engaging said leaves.
Claim 15
Dependent Claim
65 words
A rock bolt assembly as claimed in Claim 12, wherein said nut has a castellated end defining recesses and lugs and said shell thin resilient arms are of reduced width relative to the leaves defining radial openings between adjacent resilient arms about the centre of the bail-like structure whereby the nut lugs can project into the shell radial openings to locate and retain said arms.
Claim 16
Dependent Claim
37 words
A rock bolt assembly as claimed in Claim 13, wherein outer edges of said lugs are bevelled such that the lugs will not project beyond the outer face of the shell when said lugs engage the shell.
Claim 17
Dependent Claim
32 words
A rock bolt assembly as claimed in Claim 12 or 13, wherein said shell has six leaves symmetrically disposed about the central bail-like structure and said nut has a correspond-ing hexagonal shape.
Claim 18
Dependent Claim
40 words
A rock bolt assembly as claimed in Claim 11, said expansion means comprising a plug formed integral with said rod, said plug having a plurality of flat tapered faces formed symmetrically thereon corresponding to planar inner faces of the leaves.
Claim 19
Dependent Claim
40 words
A rock bolt assembly having a shell as claimed in Claim 11, 12 or 13, wherein said one-piece shell casting is formed of zinc, zinc alloy, iron or aluminum by gravity or die casting or of plastics by injection moulding.
Claim 20
Dependent Claim
32 words
A rock bolt assembly as claimed in Claim 12 or 13, wherein the small angle of inclination of the shell planar faces and of the nut planar faces is about 8 degrees.
Claim 21
Dependent Claim
23 words
A rock bolt assembly having a shell as claimed in Claim 11, 12 or 13, wherein the central bail-like structure is cylindrically shaped.
Claim 22
Dependent Claim
46 words
A rock bolt assembly having a shell as claimed in Claim 11, 12 or 19, wherein said arms of said bail-like structure permit initial resilient engagement of the leaves with the faces of the expansion means without breakage and can break during tightening of the bolt.
Claim 23
Dependent Claim
49 words
A rock bolt assembly having a shell as claimed in Claim 11, 12 or 13, wherein the opposite side edges of the leaves are bevelled parallel with radii of the cylindrical surface definable by the leaves whereby the leaves are spaced from each other upon closure of the shell.
Claim 24
Dependent Claim
40 words
A rock bolt assembly having a shell as claimed in Claim 11, 12 or 13, wherein the planar inner face of each leaf has a concave central recess formed therein at the thicker outer end to receive the bolt therein.
Claim 25
Dependent Claim
40 words
A rock bolt assembly having a shell as claimed in Claim 11, 12 or 13, wherein each leaf outer face has a flat central portion extending the length thereof providing two wide-area control zones on each said leaf outer face.
Claim 26
Dependent Claim
40 words
A rock bolt assembly having a shell as claimed in Claim 11, 12 or 13, wherein each leaf outer face has a concave central portion extending the length thereof providing two wide-area contact zones on each said leaf outer face.
References Cited (Backward Citations)
No citation records indexed.
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