TOWER CRANE BOOM Russian patent published in 2004 - IPC

FIELD: mechanical engineering; materials handling facilities. SUBSTANCE: invention relates to tower cranes with articulated sectional booms and it can be used in cranes with elongated booms featuring complex kinematics of folding the boom into inoperative position and unfolding it into working position. Proposed tower crane boom includes root and end sections with lower chords for movement of trolley and cable mechanism for holding boom in working position and folding it at mounting and increasing the height of tower. Adjacent end faces of lower chords of boom sections are provided with cavities with formation of segment. Height of segment height of segment in cross section of cylinder is less than radius of cylinder. Each axle is installed in said cavities of end faces of lower adjacent chords of boom. Boom is provided with additional hinge joints in form of two pairs of shackle connected by pins with lower chords of sections. Lower chords of boom sections are provided with lugs with lugs from lower side which get one into the other, with mounting pin fitted in holes of lugs. Holes are made for free travel of mounting pin. EFFECT: provision of compact design of boom in folded up state, convenience of mounting and demounting. 7 dwg