Abstract: A multi-level construction scaffold comprises a pair of H-shaped end frames spaced by horizontal guard rails. The guard rails are pivotally connected at opposed ends thereof to the end frame members, thereby allowing the guard rails to pivot in parallel when one of the frame member is lifted relative to the other. Each end frame includes a pair of uprights interconnected by a horizontal platform support located at a distance below the guard rails engaged with the end frames. In this way, the safety guard rails of a next level to be erected can be installed directly from the underlying level.

Abstract: An elevating platform assembly comprises a pair of laterally spaced, generally vertical masts and an elongated working platform extending generally horizontally between the masts. Hoist mechanisms act between the ends of the working platform the masts and are actuable to move the working platform along the masts to different elevations. At least one level sensor is provided on the working platform and detects when the working platform deviates from a generally horizontal orientation. At least one controller is responsive to the at least one level sensor and controls the hoist mechanisms to adjust movement of the working platform when the working platform deviates from the generally horizontal orientation thereby to return the working platform to the generally horizontal orientation.

Abstract: An elevating platform assembly includes a generally vertical mast having a generally vertical rack mounted thereon. A first trolley is coupled to the mast and is moveable therealong. A drive mechanism is carried by the first trolley and includes at least one pinion in mating engagement with the rack. An elongated elevating platform extends from the mast and has a second trolley mounted adjacent one end thereof. The second trolley couples the elevating platform to the mast and is moveable along the mast. The first trolley is coupled to at least one of the second trolley and elevating platform in a manner to maintain alignment of the at least one pinion and rack when loads are placed on the elevating platform that create moments at the mast.

Abstract: An elevating platform assembly includes a generally vertical mast having a generally vertical rack mounted thereon. A first trolley is coupled to the mast and is moveable therealong. A drive mechanism is carried by the first trolley and includes at least one pinion in mating engagement with the rack. An elongated elevating platform extends from the mast and has a second trolley mounted adjacent one end thereof. The second trolley couples the elevating platform to the mast and is moveable along the mast. The first trolley is coupled to at least one of the second trolley and elevating platform in a manner to maintain alignment of the at least one pinion and rack when loads are placed on the elevating platform that create moments at the mast.