# US 4,398,761 A · Device for lifting and tilting concrete panels > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 4,398,761 A - Document ID: US4398761A - Status: Granted - Kind: A - Application number: 06/289,712 - Filed: 1981-08-03 - Granted: 1983-08-16 - Earliest claimed: 1980-07-15 - Assignees: Fabcon, Inc. - Inventors: David W. Hanson; Richard C. Nash; Richard R. Koehn - Web page: https://patentgrep.com/patent/US4398761A ## CPC - B66C 1/427: {by hydraulic or pneumatic motors} - B66C 1/425: {motor actuated (B66C1/44, B66C1/58 take precedence)} - B66C: CRANES; LOAD-ENGAGING ELEMENTS OR DEVICES FOR CRANES, CAPSTANS, WINCHES, OR TACKLES ({specially adapted for lifting invalids A61G7/10;} rope, cable, or chain winding mechanisms, braking or detent devices therefor B66D; specially adapted for nuclear reactors G21) ## Abstract A device for both lifting and dumping of core material from long hollow core concrete panels. The device utilizes a pair of retractable clamp members to engage the longitudinal groove in the side of the panel. ## Claims ### Claim 1 Apparatus for lifting concrete panels, said apparatus including two or more lifting clamps, each of which comprises: a first beam; a second beam; a first clamping head rigidly connected to said first beam; said first clamping head constructed and arranged to engage said panel on one sidewall thereof; a second clamping head rigidly connected to said second beam, said second clamping head constructed and arranged to engage said panel on an opposite sidewall thereof; means for moving said first beam relative to said second beam to selectively engage and disengage one or both of said clamping heads from the sidewall of said panel; and connection means connected to said apparatus and constructed and arranged for connection to a lifting cable, said connection means providing for pivotal movement of said apparatus and said first and second clamping heads about an axis through said panel below said beams. ### Claim 2 Apparatus for suspension from lifting cables depending from an overhead crane, said apparatus constructed and arranged to lift and tilt concrete panels, said apparatus including two or more lifting clamps, each of which comprises: a pair of extendable beams; a pair of clamping heads, one each of which is suspended from one end of each of said pair of extendable beams, each one of said pair of clamping heads constructed to engage said panel on a sidewall thereof; connection means connected to said apparatus and said lifting cable, said connection means providing for pivotal movement of said apparatus and said pair of clamping heads about an axis through said panel below said pair of extendable beams; and means for extending and retracting said pair of extendable beams relative to each other to position said pair of clamping heads to grip said panel on adjacent sides. ### Claim 3 (depends on 2) The invention of claim 2 wherein said pair of beams includes alignment guide means for setting the vertical height of said beams above the surface of said panel and for establishing the desired angular alignment of said lifting clamps to facilitate engagement of said clamping heads with the sidewalls of said panels. ### Claim 4 (depends on 3) The invention of claim 3 wherein each of said alignment guide means comprises: alignment plate means; and linking means attached to one of said pair of beams and to said alignment plate means, said linking means is constructed and arranged for adjustable movement of said alignment plate means for controlling the alignment and vertical spacing of said lifting clamps relative to the surface of said concrete panels. ### Claim 5 (depends on 4) The invention of claim 4 wherein said linking means comprises: at least one threaded rod rotatably attached to one end thereof to said alignment plate means; receiving means mounted on one of said beams, including a threaded opening therein for receiving one of said threaded rods; and means for introducing relative movement between said threaded rod and the threaded portion of said receiving means and thereby raising and lowering said alignment plate means. ### Claim 6 (depends on 5) The invention of claim 5 wherein said threaded rod has a ball bearing attached to one end thereof and wherein said alignment plate means includes means for engaging the end of said threaded rod and for permitting rolling movement of said rod relative to said alignment plate means and the surface of said plank panel. ### Claim 7 (depends on 5) The invention of claim 5 wherein said threaded rod has a ball bearing attached to one end thereof and wherein said alignment plate means includes means for engaging the end of said threaded rod and for permitting rolling movement of said rod relative to said alignment plate means and the surface of said panels. ### Claim 8 (depends on 4) The invention of claim 4 wherein said pivotally mounted clamping heads are spring biased to a normal position and move to a gripping position against the sidewalls of said panel as said pair of extendable beams is retracted. ### Claim 9 (depends on 2) The invention of claim 2 wherein said pair of clamping heads are pivotally mounted on said pair of extendable beams to facilitate alignment with non-vertical sidewalls of said panel. ### Claim 10 (depends on 2) The invention of claim 2 wherein the engagement face of said pair of clamping heads includes a projecting portion to engage a longitudinal groove in the sidewall of said panel. ### Claim 11 (depends on 2) The invention of claim 2 wherein said connection means is a link pivotally connected at one end to one of said pair of extendable beams with the other end of said link connected to the cable suspended from said overhead crane. ### Claim 12 (depends on 2) The invention of claim 2 wherein said means for extending and retracting said pair of extendable beams to position said pair of clamping heads comprises hydraulically actuated means constructed and arranged to apply a positive clamping force on said pair of clamping heads to forceably grip the sidewalls of said panel. ### Claim 13 Apparatus for suspension from lifting cables depending from an overhead crane, said apparatus constructed and arranged to lift and tilt concrete panels, said apparatus including two or more lifting clamps, each of which comprises: an extendable beam; a pair of clamping heads suspended from each end of said extendable beam, each of said clamping heads constructed to engage said panel on a sidewall thereof; connection means connected to said apparatus and said lifting cable, said connection means providing for pivotal movement of said apparatus and said pair of clamping heads about an axis through said panel below said beam; and means for extending and retracting said beam to position said pair of clamping heads to grip said panel on adjacent sides. ### Claim 14 Apparatus for suspension from lifting cables depending from an overhead crane, said apparatus constructed and arranged to lift and tilt concrete panels, said apparatus including two or more lifting clamps, each of which comprises: a pair of beams; a pair of clamping heads, one each of which is suspended from one end of each of said pair of beams, each one of said pair of clamping heads constructed to engage said panel on a sidewall thereof; connection means connected to said apparatus and said lifting cable, said connection means providing for pivotal movement of said apparatus and said pair of clamping heads about an axis through said panel below said pair of beams; and means for moving said pair of beams relative to each other to position said pair of clamping heads to grip said panel on adjacent sides. ### Claim 15 (depends on 14) The invention of claim 14 wherein said pair of beams includes alignment guide means for setting the vertical height of said beams above the surface of said panel and for establishing the desired angular alignment of said lifting clamps to facilitate engagement of said clamping heads with the sidewalls of said panels. ### Claim 16 (depends on 15) The invention of claim 15 wherein each of said alignment guide means comprises: alignment plate means; and linking means attached to one of said pair of beams and to said alignment plate means, said linking means is constructed and arranged for adjustable movement of said alignment plate means for controlling the alignment and vertical spacing of said lifting clamps relative to the surface of said concrete panels. ### Claim 17 (depends on 16) The invention of claim 16 wherein said linking means comprises: at least one threaded rod rotatably attached at one end thereof to said alignment plate means; receiving means mounted on one of said beams, including a threaded opening therein for receiving one of said threaded rods; and means for introducing relative movement between said threaded rod and the threaded portion of said receiving means and thereby raising and lowering said alignment plate means. ### Claim 18 (depends on 14) The invention of claim 14 wherein one each of said pair of clamping heads are pivotally mounted on one of said pair of beams to facilitate alignment with non-vertical sidewalls of said panel. ### Claim 19 (depends on 18) The invention of claim 18 wherein said pair of clamping heads are spring biased to a normal position and move to a gripping position against the sidewalls of said panel as said pair of beams are retracted. ### Claim 20 (depends on 14) The invention of claim 14 wherein said clamping head includes an engagement face having a projecting portion to engage a longitudinal groove in the sidewall of said panel. ### Claim 21 (depends on 14) The invention of claim 14 wherein said connection means is a link pivotally connected to one end of each beam of said pair of extendable beams with the other end of each of said links connected to the cable suspended from said overhead crane. ### Claim 22 (depends on 14) The invention of claim 14 wherein said means for moving said pair of beams relative to each other comprises jack screw means attached to the other ends of each of said beams of said pair of beams, said jack screw means constructed and arranged to apply a positive clamping force on said pair of clamping heads to forceably grip the sidewalls of said panel. ### Claim 23 Apparatus for suspension from lifting cables depending from an overhead crane, said apparatus constructed and arranged to lift and tilt concrete panels, said apparatus including two or more lifting clamps, each of which comprises: first and second beams, each of which has a clamping head suspended from one end thereof for engagement with opposite sidewalls of said panel; means connected between said first beam and the other end of said second beam for elevating the end of said second beam relative to said first beam to selectably pivot said second beam and clamping head suspended from it into and out of engagement with sidewalls of said panel; and connection means connected to said apparatus and said lifting cable, said connection means providing for pivotal movement of said apparatus and said clamping heads about an axis through said panel below said first and second beams.