Bolt anchors

Claim 2

An anchor device for attachment within a borehole in rock or the like comprising: a cylindrical member adapted to be received in said hole. at least one longitudinal slot in said cylindrical member and a cam surface associated with said slot; rock gripping means within said slot, having a biting edge and a curved surface, generally opposite said biting edge, in engagement with said cam surface and both movable and rollable along said cam surface; means within said slot for activating said rock gripping means, so that at least a portion of said rock gripping means, as it pivots, including said biting edge, is forced out of said slot and into the sides of said borehole in securing said device in said borehole, said activating means being resilient and compressible by said rock gripping means as said member is moved into said borehole; and such compression tending to cause said biting edge to move into said rock to assist said rock gripping means to be moved into said rock by moving along and turning on said cam surface.

Claim 3

An anchor device, as set forth in claim 1, wherein said rock gripping means is provided with a wing at each side having a curved surface and a cam surface is located at each side of said slot in position for engagement with said curved surface of the corresponding wing said slot.

Claim 4

An anchor device, as set forth in claim 1, wherein said slot is covered with a wrapper for holding said rock gripping means within said slot before insertion of said device into said hole.

Claim 5

An anchor device, as set forth in claim 1, wherein: said rock gripping means comprises a pair of wedges mounted within said slot, said slot extending through said member and said wedges having engaging longitudinally curved inner edges and longitudinally straight outer edges normally aligned with the outer surface of said member; and said cam surface is formed at the inner end of said slot for engagement by a curved end of each said wedge opposite said biting edge.

Claim 6

An anchor device, as set forth in claim 1, wherein: said cam surface associated with said slot comprises an inclined edge at each side of said slot; and said rock gripping means comprises a can wedge disposed in said slot and having a wing at each side engaging the respective inclined edge.

Claim 7

An anchor device as set forth in claim 5, wherein said resilient means is a ball formed of rubber-like material.

Claim 8

A anchor device, as set forth in claim 5, wherein the inside of said cam wedge is softer arcuate.

Claim 9

An anchor device, as set forth in claim 5, wherein the inside and outside of said cam wedge are inclined toward each other in a longitudinal direction away from the initial position of said resilient means.

Claim 10

An anchor device, as set forth in claim 5, wherein said cam wedge includes: a cylindrical top having a lateral curvature corresponding to that of said member, the outer surface of said wings being a continuation of said top; a transverse front face inclined at an angle away from a perpendicular to said top; a transversely arcuate underside longitudinally inclined towards said top in a direction away from said front face; and the underside of each wing is transversely concave to fit against transversely convex surfaces of said inclined edges.

Claim 11

A bolt anchor adapted for use within a borehole in a rock or concrete wall, comprising: a cylindrical member having a longitudinal slot extending from a point at least adjacent the inner end toward the opposite end, said slot having a base inclined from said inner end to a greater depth at a point spaced therefrom; a cam roller within said slot having a transverse biting edge and a generally arcuate convex surface opposite said biting edge adapted to roll along said inclined base of said slot; said cam roller having a concave surface on one side of said biting edge and a planar surface on the opposite side of said biting edge, said generally arcuate surface adjoining said planar surface; said cam roller also having a generally semicircular knob having a radius less than said generally arcuate surface, said knob merging at one side with said concave surface and at the other side forming a notch adjoining said generally arcuate surface; resilient means in the deeper portion of said slot which is compressed by said cam roller upon movement of said member into said borehole and which causes said biting edge to engage said rock whenever said member is moved outwardly said borehole; and means for moving said member outwardly in said borehole.

Claim 12

A bolt anchor adapted for use within a borehole in a rock or concrete wall, comprising: a cylindrical member having a longitudinal slot extending from a point at least adjacent the inner end toward the opposite end, said slot having a base inclined from said inner end to a greater depth at a point spaced therefrom; a cam roller within said slot having a transverse biting edge and a generally arcuate convex surface opposite said biting edge adapted to roll along said inclined base of said slot; said cam roller having a concave surface on one side of said biting edge and a planar surface on the opposite side of said biting edge, said generally arcuate surface adjoining said planar surface; said cam roller also having a generally semicircular knob having a radius less than said generally arcuate surface, said knob merging at one side with said concave surface and at the other side forming a notch adjoining said generally arcuate surface; resilient means in the deeper portion of said slot which is compressed by said cam roller upon movement of said member into said borehole and which causes said biting edge to engage said rock whenever said member is moved outwardly said borehole; and means for moving said member outwardly in said borehole.

Claim 13

An integral bolt anchor adapted for use within a hole in a concrete wall, comprising: a bolt threaded at its outer end for receiving a nut and having a longitudinal slot adjacent the inner end thereof, said slot having a concave base; a cam roller adapted to roll along said base and having a generally arcuate convex surface resting at one point on said inclined base, a planar surface at the front and above said generally arcuate surface, a concave surface on the top and a generally semicircular knob at the upper rear having a lesser radius than said generally arcuate surface, said planar surface and said concave surface intersecting at a front upper biting edge and said knob forming a notch on the underside at the rear edge of said generally arcuate surface; and a resilient block having a generally triangular shape with the larger end abutting said cam roller in said slot and being compressed by said cam roller as saId bolt is moved into said hole and causing said biting edge to bite into the concrete when said bolt is moved outwardly in said hole, said generally arcuate surface rolling along said slot base as said bolt is moved further outwardly in said hole until said knob also engages said base.

Claim 14

An integral bolt anchor adapted for use within a hole in a concrete wall, comprising: a bolt threaded at its outer end for receiving a nut and having a longitudinal slot adjacent the inner end thereof, said slot having a concave base; a cam roller adapted to roll along said base and having a generally arcuate convex surface resting at one point on said inclined base, a planar surface at the front and above said generally arcuate surface, a concave surface on the top and a generally semicircular knob at the upper rear having a lesser radius than said generally arcuate surface, said planar surface and said concave surface intersecting at a front upper biting edge and said knob forming a notch on the underside at the rear edge of said generally arcuate surface; and a resilient block having a generally triangular shape with the larger end abutting said cam roller in said slot and being compressed by said cam roller as saId bolt is moved into said hole and causing said biting edge to bite into the concrete when said bolt is moved outwardly in said hole, said generally arcuate surface rolling along said slot base as said bolt is moved further outwardly in said hole until said knob also engages said base.