SU1227594A1 - Cargo handling crane telescopic jib - Google Patents

Description

This invention relates to a lifting and transport engineering and can be used in jib cranes.

The purpose of the invention is reliability.

FIG. 1 shows schematically a telescopic boom of a crane in the extended state, general view; in fig. 2 - the same, folded; in fig. 3 is a section A-A in FIG. one; in fig. 4 - section BB-n FIG. 2

The telescopic boom contains a stationary section of the box section, consisting of the lower flange 1 (Fig. 0, parallel to the longitudinal axis of the boom, side walls 2, made with a bevel along the upper edge, forming an angle about the axis of the boom axis, while the apex of the triangular side walls 2 cut in the transverse dimension b, and the upper flange 3; In the upper part of the fixed section on the lower shelf a pair of roller carriages 4 (Fig. 1 and 3) are hinged; they serve as supports for the movable section 5, which is inserted during assembly. The cut is at its base, since the size L of the latter exceeds the size B of the head of the movable section 5, At the interface between the sections, besides the roller carriages 4, there are rollers 6 (Figs 1 and 4) and a shaft 7 mounted in the openings of the side walls above the base of the movable section 5 with the possibility of rotation in the hubs 8 (Fig. 4), whose aperture is offset by an eccentric S relative to the external mounting diameter. The hubs 8 could be tangentially rotated in the aperture of the movable section 5 to the maximum of the eccentricity S followed by rigid fixation of the polo screws 9. At this point, the side walls of the movable section 5 are reinforced with overlays 10. On the shaft 7 in the groove 11. one end of the tape 12 is fixed, and the other end of which is attached by a strap 13 (FIG. 1) to the base of the upper shelf 3 of the fixed section. The tape 12 can be made as a conveyor of rubberized fabric cord reinforced for strength and rigidity with flexible steel wire mesh. It is also possible to use a strap tape, including a set along the length of the shaft 7 (Fig. 4) from individual coils of smaller width.

Selection of the thickness of the tape produced

on the basis of the boom design, depending on the length of the spacing of the section and the bevel of their side walls. The tape 12 is wound on the shaft 7 to install the sections with a minimum eccentricity

S, and after installation, increasing the eccentricity, press it. In the upper part of the fixed section (Figs. 2 and 3), the bolts 14 install, after assembling the sections, the guides 14, which interact with the keys 15 welded -DON the movable section 5. The gap q in this interface supports the movable section 5 on the roller carriages 4, and the interface itself prevents the vertical section of the movable section in the transport position of the truck crane. The hydraulic extension of the boom sections is served by the hydraulic cylinder 16- (Fig. 1), mounted on the fingers 17 in the walls of the sections reinforced with the pads 18.

The device works as follows.

At inclusion of a hydraulic cylinder 16

The boom extends from the position in FIG. 2 to the position in FIG. 1, the shaft 7, turning, smiling, removes the tape 12; the radius of this rolling support decreases, and the axis of the shaft 7 follows parallel to the boom axis when there is constant contact of the upper flange of the fixed section with the movable section 5. The stiffness of the tape 12 prevents the movable section 5 from bending relative to the boom axis, and the slight damping of the tape 12 contributes to a smooth load of the metal structure arrows. When the movable section 5 is pulled in due to the preliminary compression of the tape 12 by rubbing it onto the upper shelf 3, it is wound onto the shaft 7. The length of the tape 12 must be such as to ensure at least 2-3 turns on the shaft 7 with the full extension of the movable section. To ensure effective friction between the tape 12 and the lower plane 3, the latter can be processed by an electric spark

sprayed or made of corrugated steel.

(rig. 3

16 j

15

Editor A. Ogar

Compiled by L. Makeeva Tehred N. Bonkalo

Order 2257/24 Edition 799 Subscription

VNIIPI USSR State Committee

for inventions and discoveries 113035, Moscow, F-33, Raushsk nab., 4/5

Production and printing company, Uzhgorod, st. Project, 4

Proofreader S. Shekmar

Claims (1)

TELESCOPIC BOOM OF A LOADING CRANE containing rolling bearings for a retractable section, including each roller carriage and an extension drive made by box sections in cross section. characterized in that, in order to increase reliability, it is equipped with a shaft installed in the upper part of the base of the side walls of the drawer section, and a tape, one end of which is mounted on the shaft and the other in the upper part of the base of the previous section, while the boom section and the housing of each roller carriage is made with decreasing height to the tip. phi. " 1