TELESCOPIC LADDER AND TOWER CRANE MEMBER MOVING UP AND DOWN THE LADDER Russian patent published in 2002 - IPC

FIELD: tower cranes. SUBSTANCE: invention relates to device combing telescopic extensible ladders with movable member moving up and down the ladders and designed for use on tower crane with telescopic mast. Telescopic mast consists of three members and it is furnished with telescopic extensible ladder also consisting of three members 14, 15 and 16. Corresponding member of telescopic ladder is coupled with corresponding member of said telescopic mast. Member 14 said ladder coupled with lower outer member of telescopic mast has two vertical uprights 22 of square or rectangular cross-section intercoupled by cross members 23. Member 16 of said ladder coupled with upper and inner members of telescopic mast is also provided with two vertical uprights 24 of square or rectangular cross-section intercoupled by cross members 25. Members 15 of said telescopic ladder coupled with intermediate member of telescopic mast has vertical uprights 26 with toothed cross-section enclosing vertical uprights 22, 24 of two other members 14, 16 of ladder. Movable member directed by said ladder has guide frame. Bearing structure 32 of guide frame has two identical systems of guide rollers arranged, respectively, in base of guide frame and on its top. First guide rollers 33 are arranged opposite to left-hand and right-hand side surfaces of said ladder, and other guide rollers 37, 38, 39, 40, 41 and 42 clamp, in pairs, vertical uprights 22, 24, 26 of members 14, 15, 16 of telescopic ladder passing in concave parts 27 of vertical uprights 26 of said member 15 of telescopic ladder. Said movable member is made, particularly, in form of control cab of said tower crane. EFFECT: provision of smooth non-interrupter transfer from one member of ladder to other member by reliable and fitted-to device of simple and compact design. 3 cl, 5 dwg