Lift system for tilt-up walls

Apparatus for putting up a tilt-up wall section comprising a hoisting cable, a shackle connected to the cable, a ring clutch interconnecting the shackle with an anchor emplaced in the wall section, the ring clutch comprising a ring having a split therein and an arcuate locking bolt rotatable relative to said ring between a locked condition extending across the split and a released condition removed from the split, said bolt having an elongated lever arm extending generally parallel to the wall section during lifting and in the direction of the upper end thereof, a release cable attached to the distal end of the lever arm to remotely operate the lever arm by rotating it outwardly and downwardly to a predetermined degree relative to the wall section to rotate the bolt to the released condition and disconnect the ring clutch from the anchor, and hoisting cable-controlled means to selectively block or allow rotation of the lever arm to said predetermined degree, said means being operated responsive to the application of lifting force to the hoisting cable to block rotation of the lever arm upon the application of lifting force to the hoisting cable and release the arm for rotation upon slacking off of the hoisting cable.