DEVICE FOR SAFE OPERATION AT HEIGHT Russian patent published in 1994 - IPC

FIELD: construction. SUBSTANCE: device consists of base, working platform, and cross-piece, which are detachably connected to one another and tied by two lines of guide rope. With flat drum of base unlocked, working platform with operator is lifted by crane hook up to boom head. Installed on stops of working platform is cross- piece; arresters, in this case, are released under the action of shackle through levers. Crane hook is engaged in shackle. Operator turns ring of cross-piece and suspends its ties on ends of boom head axle. Turning of ring results in change of angle of turning of working platform in vertical plane relative to plane of location of crane boom. Further, working platform is lowered on base carrying balance weight. Working platform is displaced by crane hook over lines of guide rope stretched between base and cross-piece. EFFECT: higher efficiency. 20 dwg