Abstract: A roof support pin for insertion into a roof bore having an opening comprising an elongate tube for insertion into the bore, the tube being compressed prior to insertion of the tube into the bore opening so that the tube expands to frictionally engage the bore a distance from the bore opening. In one embodiment, a roof support plate has a hole with a diameter smaller than the diameter of the bore. The plate hole compresses the diameter of the tube upon insertion of the tube into the bore through the plate hole. In another aspect, a plurality of rings longitudinally spaced axially on and retain the tube compressed prior to insertion of the tube through the plate hole into the bore. The rings slidably engage the tube for retention at the plate for allowing the tube to expand within the bore. In yet another embodiment, a spiral strip wraps and retains the tube compressed prior to insertion into the bore. The spiral strip is stripped from the tube as the tube is inserted through the plate hole.

Abstract: A roof support pin for insertion into a roof bore having an opening comprising an elongate tube for insertion into the bore, the tube being compressed prior to insertion of the tube into the bore opening so that the tube expands to frictionally engage the bore a distance from the bore opening. In one embodiment, a roof support plate has a hole with a diameter smaller than the diameter of the bore. The plate hole compresses the diameter of the tube upon insertion of the tube into the bore through the plate hole. In one aspect, the tube includes adjacent opposed longitudinal edges forming a longitudinal slit. The tube edges engage and are turned resiliently inwardly of the tube at the longitudinal slit as the tube is circumferentially resiliently compressed, and resiliently coacting to provide an expansion force for frictional engagement of the tube with the bore.

Abstract: The stabilizer comprises an elongate support tube having a split extending generally lengthwise responsive to peripheral compression of the tube to cause contraction of cross-sectional dimension and cause frictional engagement with the surface of a bore in an earth structure for anchoring the tube within the bore. A sleeve located about and fixed to the driven end of the tube provides an impact surface for accepting insertion forces for driving the tube into the bore. A support plate having a hole with cross-sectional dimensions smaller than the cross-sectional dimensions of the bore is positioned relative to the earth structure with the hole substantially aligned with the opening of the bore. The plate hole compresses the tube upon insertion of the tube into the bore through the plate hole, the tube expanding after passage through the plate hole to frictionally engage the surface of the bore in spaced relation to the bore opening.

Abstract: A roof support pin for insertion into a roof bore having an opening comprising an elongate tube for insertion into the bore, the tube being compressed prior to insertion of the tube into the bore opening so that the tube expands to frictionally engage the bore a distance from the bore opening. In one embodiment, a roof support plate has a hole with a diameter smaller than the diameter of the bore. The plate hole compresses the diameter of the tube upon insertion of the tube into the bore through the plate hole. In another aspect, a plurality of rings longitudinally spaced axially on and retain the tube compressed prior to insertion of the tube through the plate hole into the bore. The rings slidably engage the tube for retention at the plate for allowing the tube to expand within the bore. In yet another embodiment, a spiral strip wraps and retains the tube compressed prior to insertion into the bore. The spiral strip is stripped from the tube as the tube is inserted through the plate hole.

Abstract: A roof support pin for insertion into the strata of the roof including an elongate rod having a non-circular cross-section to provide corners, the rod being twisted so that the corners provide longitudinal substantially helical fins for turning into and gripping the roof strata as the rod is inserted into the roof. A roof support plate is provided with an aperture having a cross-section with corners that engage the corners of the rod cross-section for turning the rod into the roof strata as the rod is moved longitudinally relatively through the aperture. The roof support plate grips the roof and precludes relative turning of the plate and roof as the rod is moved longitudinally through the plate aperture and is twisted into the roof strata.

Abstract: A roof pin particularly adapted for mine or tunnel roof support in which the strata-gripping assembly has a plurality of locking discs mounted on and carried by one end of an elongate rod, the locking discs being resilient and having a periphery adapted to engage the strata defining the roof pin hole. Spacers are mounted on and carried by the rod end, and are located between and engage each axially adjacent pair of locking discs, the spacers having a periphery located radially inward of the locking disc periphery. A retainer on the rod at opposite ends of the strata-gripping assembly holds the discs and spacers on the rod end. The locking discs have downturned peripheries adapted to engage the roof strata and flex resiliently downwardly and inwardly upon insertion of the pin, and expand upwardly and outwardly upon application of a load force on the pin during roof support.

Abstract: A point-attack bit retained for rotation in a block bore, and used for removing material from a mine face. The bit has an elongate shank, and a head integral and coaxial with the shank, the head including a plurality of peripherally spaced, laterally projecting vanes extending generally longitudinally of the bit. Each vane is substantially triangular with a narrow leading end and a wider trailing end, and has sides that extend from the leading end to the trailing end. One of the vane sides has a different angle with respect to the longitudinal axis of the bit than the other vane side to provide different transverse forces on the vane sides upon contact with material being mined to effect a positive turning of the bit upon picking of the mine face.

Abstract: A point-attack bit retained for rotation in a block bore, and used for removing material from a mine face. The bit has an elongate shank, and a head integral and coaxial with the shank, the head including a plurality of peripherally spaced, laterally projecting vanes extending generally longitudinally of the bit. Each vane is substantially triangular with a narrow leading end and a wider trailing end, and has sides that extend from the leading end to the trailing end. One of the vane sides has a different angle with respect to the longitudinal axis of the bit than the other vane side to provide different transverse forces on the vane sides upon contact with material being mined to effect a positive turning of the bit upon picking of the mine face.