BOOM CRANE Russian patent published in 1995 - IPC

FIELD: materials handling equipment engineering. SUBSTANCE: boom crane has running gear on which turnable is installed. Boom is installed on turnable for turning around horizontal axis. Fitted in upper part of boom is jib with load gripper. Power hydraulic cylinder provides turning of jib relative to boom. Hinge-mounted on boom is bracket which carries operator's cabin. Bracket, tie-rod and sections of boom and turnable form articulated parallelogram; owing to this cab preserves its position independent of angle of tilting of the boom. Tie-rod is made in form of two parallel links hinge-connected on turnable and bracket to form articulated parallelogram. Hinge-connected steps are arranged over entire length of links. Length L of steps is equal to distance H between steps on link. Thanks to it the steps, with boom in horizontal position, form solid floor convenient for moving along. EFFECT: enlarged operating capabilities. 3 cl, 3 dwg