FR2539731A1 - LIFTING MECHANISM FOR CONSTRUCTION CRANES - Google Patents

Abstract

THE INVENTION RELATES TO A LIFTING MECHANISM FOR CONSTRUCTION CRANES INCLUDING A CABLE DRUM AND A LOAD RECEIVER. TO OBTAIN A RELATIVELY FAVORABLE CABLE DEFLECTION ANGLE, THE CABLE RETURN PULLEY 6 WHICH IS CLOSEST TO THE LIFT DRUM IS MOUNTED SO THAT THEY CAN BE SWIVEL INDIRECTLY AROUND A HORIZONTAL AXIS ORIENT HORXENDICALLY CENTRAL AND PERIODICALLY. LONGITUDINAL OF A HORIZONTAL PIN 11 OF A SUSPENSION CARRIER PART 9, THE POSSIBILITY OF PIVOTING OF THE CABLE RETURN PULLEY 6 BEING ESTABLISHED BY A CLASSIC HINGED BEARING 13, 15. APPLICATION TO ROTATING LATHE CRANES.

Description

The present invention relates to a lifting mechanism for cranes

  construction, in particular tower cranes, having a lifting drum for a large accumulation of cable and cable return pulleys between the lifting drum and an absorption means

charge.

  In tower cranes

  high rise or in construction cranes.

  similar with relatively high lifting heights, for example 50 m and more - it is necessary to achieve a large accumulation of cables, first of all to choose a cable drum having

  a relatively large diameter and a relative length

  large, and secondly to wind the hoisting rope in several layers Because, due to the construction of the crane, the spacing between the hoist drum and the nearest cable pulley, which is mounted on a fixed shaft supported in corresponding recesses of the crane frame, is more or less fixed, we obtain, for a relatively long lifting drum, relatively large cable deflection angles, which is

  unfavorable with regard to the hoisting behavior

cable.

  The object of the invention is to improve a mechanism

  crane lifting device of the type defined above so that also when using a relatively long lifting drum, having a relatively large diameter and a relatively small cable receiving notches, it is can obtain, without having to modify on the crane frame the spacing, predetermined by the construction of the crane, between the lifting drum and the nearest cable pulley, deflection angles

relatively favorable cable.

  This problem is solved according to the invention in that the cable pulley closest to the lifting drum can pivot indirectly about a horizontal axis placed perpendicular to the longitudinal central axis of a horizontal pin

a suspended carrier.

  By the means according to the invention, the hoisting rope remains, due to the automatic adjustment (inclined position) of the cable pulley, completely on its line of action in the bottom of the cable notch The deflection of the lifting cable with respect to the mounted rope pulley

in an articulated way is minimal.

  An economically favorable structure providing the possibility of pivoting is obtained when, in accordance with another characteristic of the invention, an articulation bearing is used.

Trade.

  According to another advantageous arrangement of the crane lifting mechanism according to the invention, in which the carrier part is provided with a forked shape at its end facing the

  cable pulley and has trans-

  versaux for receiving the shaft on which is mounted rolling the cable pulley, is that the carrier portion comprises at its end opposite the cable pulley pulley, a horizontal transverse hole whose diameter is substantially larger than the diameter of the spindle through the hole

  transversal and is supported in corresponding recesses

  of a frame part of the crane, and in that it is provided in the annular volume existing between the

  pin and the wall of the transverse hole the inner ring

  and the outer ring-of a hinge bearing.

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  The use of the hinge bearing without

  and the rolling bearing with permanent lubrication

  In addition, it is possible to have a relatively short spacing between the positions of the bearings of the spindle, which has a favorable influence on the design of the spindle.

spindle diameter.

  Other features and advantages of the invention will be highlighted in the following

  description, given as a non-standard example

  limiting, with reference to the accompanying drawings in the-

  Figure 1 is a side view of the top of a tower crane, and Figure 2 shows the cable return pulley, including its suspension, partly in section.

and on an enlarged scale.

  The tower crane comprises among others an arrow 1, a counterweight arrow 2 and

an upper part of the tower 3.

  On the arrow-to-counterweight 2 is arranged a

  lifting drum 4 can be driven by motor.

  The lifting drum 4 is arranged in the form of an accumulation drum of the lifting cable 5 to be wound up in several layers; thus there is provided a lifting drum 4 having a relatively large diameter, a relatively long length and a relatively small cable receiving notches slot. The lifting cable 5 from the lifting drum 4 passes on a first

  pulley 6 (the nearest), that is.

  pivotally suspended from the frame of the upper part

  3 to a level higher than that of the lifting drum, then it passes on a second deflection pulley 7, placed in a fixed position near the end of arrow 1 placed on the tower side, then if necessary on other pulleys or rope pulleys to reach a fixed point on the support

lifting hook.

  The cable return pulley which is closest to the lifting drum 4 is mounted in a known manner via bearings 17 on a non-rotating shaft 8 The shaft 8 is supported in corresponding holes of a part carrier 9 arranged with a forked shape at this end 9a, or in a similar manner The bar-shaped end 9b, opposite the shaft 8, of the carrying part 9 has a transverse hole 10 through which is

  guided a horizontal pin it of a sensible diameter-

  smaller and which rests on each side in a recess formed in corresponding flanges 12 or the like, which are fixed on the frame of the part

  3 The spindle is fixed without possibility

bility of axial translation.

  On the spindle There is arranged in the middle the inner ring 13 of a hinge bearing which has a spherical outer surface of convex profile The axial attachment of the inner ring 13 is provided by means of two spacing sleeves 14a , 14b, which bear at one end against the front surfaces of the inner ring 13 and

  the other end against the integral side surfaces

  The inner ring 13 clings around an outer ring 15 having a cylindrical outer surface adapted to the diameter of the transverse hole 10 and a concave spherical inner surface. The outer ring 15 is fixed axially in a known manner by example by means of rings of

  corresponding security 16 (rings of the Seeger type).

  The outer ring 15 and the inner ring 13

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  constitute what is called a hinge bearing, which allows a rotation of the cable pulley 6 around the longitudinal central axis of the pin Il and a limited pivoting of the carrier part 9, including the pulley of cable return

  6, about a horizontal axis, oriented perpendicular-

  to the central longitudinal axis of spindle II.

Claims (3)

  1 Lifting mechanism for construction cranes, especially tower cranes, having a lifting drum for a large accumulation of cable and cable return pulleys between the lifting drum and a load-absorbing means, characterized in that the rope pulley (6) closest to the lifting drum (4) can pivot indirectly about a horizontal shaft placed perpendicularly to the longitudinal central axis of a horizontal spindle   (11) a suspension carrying part (9).   Lifting mechanism for cranes according to claim 1, characterized in that the possibility of pivoting of the rope return pulley (6) is established by a conventional type hinge bearing. (13, 15).   3 crane lifting mechanism according to claim 1, o the carrier portion is arranged with a forked shape at its end facing the cable pulley and has transverse holes for receiving the shaft on which the pulley of return is mounted with bearing, characterized in that the carrier part (9) has, at its end opposite to the cable return pulley (6), a horizontal transverse hole (10) whose diameter is substantially larger than the diameter of the pin (11), passing through the transverse hole (10) and supported   in corresponding recesses of a part of   of the crane, and in that the inner ring (13) outer ring (15) of a hinge bearing.