Abstract: A shackle for supporting a platform support on an, upright comprising a first side member and a second side member, an inner load bearing jaw and an outer load bearing jaw mounted on the first and second side members with the inner load bearing jaw for engaging a first surface of the upright and the outer load bearing jaw for engaging a second surface of the upright, and a locking jaw mounted on the side members and movable between an upright engaging condition to prevent the lowering of the shackle on the upright and an upright non-engaging condition to allow for the lowering of the shackle on the upright.

Abstract: A clamp for mounting an angle bracket on a tubular upright having a side member, an outer jaw and an inner jaw coupled to the side member, and coupling means permitting the side member to pivot relative to the angle bracket about a fixed or non-fixed pivot axis. The inner and outer jaws preferably feature contact surfaces that are portions of circular, cylindrical outer surfaces, but in any case are shaped to contact the cylindrical outer surface of the upright. The clamp is attached to the angle bracket and the jaws are pivotally mounted in the clamp so that the jaws have the necessary number of degrees of freedom with respect to the side member to permit them to contact the upright on extended areas.

Abstract: An angle bracket constructed from a single piece metal blank. The bracket is of a substantially triangular shape. In one embodiment of the invention the bracket has a U-shaped cross-section providing added stability. A method is disclosed for constructing the bracket from the metal blank. The method includes the steps of folding the metal blank along preformed fold lines to form its triangular shape. The method also includes the steps of folding the metal blank along additional preformed fold lines to form its U-shaped cross-section.

Abstract: A plurality of scaffolds stacked one above the other on a support and each scaffold supported on two laterally spaced self-locking scaffold brackets attached to the supports by load-activated locks. A hoisting mechanism is selectively connected to the scaffolds in such a way as to lift each of the scaffolds up sequentially into its final position. Mechanical jacks connected to the load activated locks are used for final small adjustment of the positions of the scaffolds. The jacks are disabled without removing them during the time that the scaffolds are being moved up or down.