EP2976287A1

EP2976287A1 - Crane boom and crane

Info

Publication number: EP2976287A1
Application number: EP14711449.0A
Authority: EP
Inventors: Günter Lehner
Original assignee: Liebherr Werk Biberach GmbH
Current assignee: Liebherr Werk Biberach GmbH
Priority date: 2013-03-22
Filing date: 2014-03-19
Publication date: 2016-01-27
Anticipated expiration: 2034-03-19
Also published as: CN105143090B; CN105143090A; EP2976287B1; WO2014146791A1; DE102013005052A1; US20160068375A1

Abstract

The invention relates to a crane boom for a crane, said crane boom consisting of an upper beam and two lower beams which are connected to each other by means of latticework and form a triangular boom cross-section, the boom cross-section comprising, at least in sections, a triangular cross-sectional shape in which the upper beam extends eccentrically. The invention also relates to a crane having such a crane boom.

Description

Crane boom and crane

The invention relates to a crane boom for a crane with a triangular boom section and a crane with such a boom.

The invention is based on proven and torsionally rigid arms with triangular cross-section. For clarity, Figure 1 shows a sketch of a typical boom cross-section. This boom includes the two lower straps

B, C and the upper flange A. All straps are connected to each other via truss diagonals, the so-called gratings.

The usual triangular cross-sections, starting from the top flange A, are an isosceles triangle whose sections A-B (triangle side 1) and A-C (triangle side 2) have identical lengths. The top chord A is thus located above halfway B-C (triangle side 3) between the bottom chords B and

C. The bisecting line 4 cuts the distance BC in the middle. In addition, the angles α, ß of the lower chords B, C are identical or almost identical. For transport from and to the place of use, it is desirable in cranes of this type to reduce their geometric dimensions as much as possible, especially for road transport, in order, for example, to comply with the requirements of the Highway Code or to reduce the transport costs incurred. In the prior art, this can be found different solution variants. For example, the entire boom cross section is reduced until the geometric dimension meets the requirements of road transport. However, this procedure can lead to statically unfavorably small and thus heavy and elastic boom cross-sections.

From DE 20 42 335 a crane with two boom parts is known, which are pivoted to reduce the transport height about a horizontal axis against each other. Before pivoting, however, the boom parts must first be moved in the axial direction to each other. This increases the effort and possibly requires additional equipment components, such as a motorized sliding drive. The biggest disadvantage, however, is that the conventional cantilever form does not achieve a satisfactory minimization of the space required.

Furthermore, it is known to form boom parts to be placed relative to each other at least partially as a so-called "open U." The boom part designed as "open U" accommodates the folded boom area in the formed interior of the "U-shape", whereby the total transport height is reducible.

However, the U-shape of the cantilever system has some disadvantages compared to the conventional triangular shape. In particular, the U-shape requires two upper straps, resulting in an increase in boom weight and an increase in manufacturing cost. In addition, open cross-sections are extremely torsionally soft. These can be used in rapid-erecting cranes only in those boom areas, which during crane operation or during crane installation only small torsional forces, eg. B. caused by wind exposed are. As a consequence threatens a limitation of the maximum allowable wind speeds during crane operation or during crane installation, which would run counter the versatility of such cranes.

An alternative boom design as a telescopic boom is costly and generates extra weight, in particular by the overlapping in the telescopic boom arms parts. Furthermore, due to the overlap, the actually existing boom length can not be optimally utilized. In addition, special provisions must be made for telescopic jibs for the use of a trolley operation, since different telescopic shots, for example, require a lane change of the trolley.

Object of the present invention is therefore to develop a generic crane such that it can be positioned more compact to each other in the transport height and / or in the transport width and also no appreciable impairment of the proven and torsionally rigid boom section must be taken into account.

This object is achieved by a crane boom according to the features of claim 1. Further advantageous embodiments of the crane boom according to the invention are the subject of the dependent claims.

According to claim 1, a modified cantilever cross-sectional shape is proposed, whereby two cantilever parts are interleaved with each other to be positioned more compact to each other either in the transport height and / or in the transport width. The crane boom has two lower chords and a top chord, which are interconnected by means of gratings and form a triangular cross-sectional shape. The modified cantilever cross-sectional shape has, at least in sections, a triangular cross-sectional shape with an eccentrically extending upper flange. The triangular shape thus formed no longer corresponds to an isosceles triangle. The upper flange is not on the bisector of the The lower straps connect triangle side, but moves closer towards one of the two lower straps.

The largest space savings in crane transport results when the crane boom at least partially has a right-angled or nearly rectangular triangular shape.

With this modified cross-sectional shape two cantilever parts can be nested together so that most favorable If the transport dimensions, in particular with respect to the height and / or width of the boom, only slightly larger than if only one boom part would be transported. As a result, the prescribed or desired transport heights and / or transport widths can be maintained more easily or more jib parts can be accommodated in the same space.

Ideally, at least those boom sections on the boom cross-sectional shape according to the invention, which are to be positioned next to each other for transport or each other.

In particular, at least two cantilever parts are interleaved or positioned next to one another in such a way that their longest triangular sides or, in the case of a right-angled triangle, their hypotenuses are placed against one another.

In a particularly advantageous embodiment of the invention, the longest side of the triangle or the hypotenuse of the boom cross-section connects the upper flange to a lower flange of the crane jib. As a result, the remaining sides of the triangle connect the top flange to the remaining bottom flange and the two bottom straps to each other. In particular, a catheter of the triangular shape formed leads from the top chord to the remaining chord and the second chord connects the two bottom chords of the jib. In this advantageous construction, the upper flange is approximately perpendicular above one of the lower chords of the triangular shape. The connection of the upper belt on the hypotenuse can be done either with the first or second Untergurt.

According to a first embodiment, the crane boom comprises at least two boom pieces, which are removable for road transport or the storage of the boom. The at least two boom pieces can therefore be positioned interleaved with each other so that most favorable case, the transport dimensions only slightly larger than the dimension of a single boom part fails. Prescribed or desired transport heights or transport widths are easier to comply with and more cantilever parts can be accommodated in the same space. This applies equally to road transport, where in particular legal provisions have to be observed, as well as for container transport, where often the maximum maximum is limited.

As a useful further embodiment of the invention, it is proposed that at least two boom sections are mounted pivotably relative to one another about a pivot axis, in particular a horizontal pivot axis. As a result, both boom areas can be pivoted relative to each other or folded together to minimize the resulting transport dimension of the crane during road transport can.

At best, the at least two boom sections can be swiveled by nearly 180 ° relative to each other, whereby the boom sections for crane transport can be applied to one another or one above the other, in particular their longest triangular sides or hypotenuses can be placed against one another.

Ideally, the upper chords of the at least two boom sections extend laterally offset relative to one another during crane operation. Particularly preferably, the boom areas are constructed mirror-inverted, ie the longest sides of the triangle or hypotenuses of the boom sections connect different lower straps to the upper strap. This gives rise to the possibility that these two cantilevers che with mutually offset boom upper belt against each other by 180 ° for transport are pivotable and can be applied to each other, so that the resulting cross-sectional shape and thus in particular increased height in interleaved boom sections during transport only insignificantly compared to the dimension of a single boom part. In particular, such an advantageous construction of the crane jib results in both boom areas being able to pivot against one another in such a way that the longest triangular sides or hypotenuses of the respective boom cross-sections lie against one another.

Depending on the desired height reduction, the horizontally oriented pivot axis is arranged in the range between half the system height of the crane jib and the plane of the upper chord. As a result, the boom parts can only be positioned relative to one another by pivoting this axle for transport in the sense of the invention.

Of course, the crane boom according to the invention is not reduced to such a modified boom cross-section. For example, there is a possibility of combining a wide variety of boom sections with the boom shape according to the invention. For example, in addition to a section with the shaping according to the invention, the cantilever may be designed with at least one cantilever triangular cross-sectional shape forming the cantilever region. The transition between different boom sections with different boom sections may require the integration of one or more transition pieces.

The solution according to the invention makes it possible in a simple way to integrate a cat operation on the boom. For this purpose, it may be advantageous if the two lower chords form a Katzfahrbahn.

The invention further relates to a crane, in particular a rapid-erecting crane or a top-slewing crane, with a crane boom according to the present invention or an advantageous embodiment of the invention. Obviously apply to the crane according to the invention the same advantages and properties as for the crane boom according to the invention, which is why at this point a repetitive description is omitted.

Further advantages and details of the invention will become apparent from the exemplary embodiments illustrated in the drawings. Show it:

FIG. 1 shows a sketch of the triangular cross section of a crane jib known from the prior art,

FIG. 2: a sketch of the triangular cross section according to the invention for a

Boom,

FIG. 3 shows a sketch of two boom parts known from the prior art during crane transport,

FIG. 4 is a sketch of two crane boom parts according to the invention during crane transport;

FIG. 5 shows a sketch of the collapsed crane jib of a fast-erecting crane according to the prior art,

FIG. 6 shows a sketch of the folded crane jib of a quick-erecting crane according to the invention,

FIG. 7 shows perspective detailed views of the crane jib according to the invention for a rapid-erecting crane,

FIG. 8: detailed cross-sectional views of the crane boom according to the invention from FIG. 7 for a rapid-erecting crane, FIG. 9 shows a sketch of the triangular cross-section according to the invention for a crane boom according to an alternative embodiment,

FIG. 10 shows a sketch of two crane boom parts according to the invention according to FIG. 9 during crane transport and FIG

FIG. 11: a sketch of a collapsed crane boom of a quick-erecting crane according to the invention according to an alternative embodiment comprising crane boom parts according to FIG. 9.

Reference has already been made in detail to FIG. 1 in the introductory part, which is why no repeated explanation is given here. Figure 2 shows the opposite a sketched cross-sectional view of the crane boom according to the invention, which is characterized by a modified triangular cross-section.

The invention is based on the proven and torsionally rigid boom structure with triangular cross-section. Analogous to the prior art, this cantilever shape has two lower chords B, C and a top chord A, wherein all straps are interconnected by means of truss diagonals, the so-called grating.

Unlike the embodiment of FIG. 1, the modified cantilever cross-section does not form an isosceles triangle, but a right-angled or approximately right-angled triangle with the straps A, B and C as corners. A first catheter as a distance AC (triangle side 20) runs from the upper belt A to lower belt C, while the second catheter runs as a distance BC (triangle side 30) from the lower belt B to the lower belt C. The distance AB (triangle side 0) then forms a hypotenuse from the upper belt A to the second lower belt B. The upper belt A is therefore located approximately vertically above the lower belt C. The right angle is located at the lower belt C. The cantilever shape according to the invention is of course not limited to the illustration according to FIG. The structure of the cantilever may as well be mirrored so that the hypotenuse is formed by the distance AC.

With this cross-sectional shape, two cantilever parts can be nested together so that at best the transport dimension with respect to their height or width is only slightly larger than when only one boom part is transported. To clarify this advantage, reference is made to the figure representation of Figures 3 and 4. Both figures show a crane boom, which consists of at least two separate boom parts 5, 6, 50, 60, which are dismantled for crane transport and positioned side by side on a means of transport, not shown.

Figure 3 corresponds to a known from the prior art crane boom with the usual triangular cross-section. The illustration shows a cross section through the longitudinal axis of the adjacently positioned boom parts 5, 6. A first boom part 5 is placed with its lower straps B, C on the transport surface of the transport, whereas the second boom part 6 rotated about its longitudinal axis with the upper flange A 'on the transport surface is stored. As can be seen from FIG. 3, the transport width Br increases at least by more than half the system width of the boom pieces 5, 6.

FIG. 4 shows the advantages of the cross-sectional area according to the invention of the cantilever according to the invention. The boom or individual lattice pieces of the jib have the same height and width as the boom according to Figure 3 in crane operation. Due to the rectangular triangular cross-sectional area, however, the two cantilever parts 50, 60 with their hypotenuses (distances AC and A'-C) can be placed against each other, so that neither the transport height H nor the transport width Br is significantly greater than the geometric dimension of a single cantilever piece 50, 60 increased. As a result, the prescribed or desired transport heights or transport widths can be more easily met or more jib parts can be accommodated in the same space. this applies equally for road transport, which is bound by legal regulations, as well as for container transport, for which maximum maximum dimensions are often valid.

Another embodiment can be taken from FIGS. 5 and 6, which respectively show sketched cross-sectional views through two cantilevered jib parts of a crane jib for a rapid-erecting crane. In this crane, the crane boom or at least two crane arm parts can be pivoted about a horizontally extending pivot axis 100 against each other for transport from and to the point of use, so that they are folded together during crane transport to reduce the entire crane length.

FIG. 5 shows a schematic representation of a conventional crane jib whose cross section has an isosceles triangle. The crane jib tip 7 is thereby folded over the pivot axis 100 by 180 ° upwards and backwards relative to the remaining stationary crane jib part 8, so that the two crane jib parts 7, 8 lie on one another. In particular, the two upper straps A, A 'of the crane arm parts 7, 8 run parallel and lie against each other. As can be seen from FIG. 5, the transport height H of the resulting collapsed crane jib is thereby at least doubled by the system height of the individual crane jib part 7, 8.

In contrast, a significant gain in space can be achieved by the modified boom cross-section in a fast-erecting crane according to Figure 6. Again, the boom or individual lattice pieces in crane operation the same height and width as the boom according to Figure 5. Due to the modified boom cross-section, however, the total transport height H is only slightly increased compared to a single boom part 70, 80. The resulting transport width remains virtually unaffected.

Analogous to FIG. 5, the cantilever tip 70 is also folded over a horizontally extending pivot axis 100 by 180 ° upwards or rearwards. The hypo- Nusen (distances AB, A'-C) of the boom sections of both boom parts 70, 80 are adjacent to each other, similar to the representation of Figure 4.

In order to achieve the best possible gain in space for transport, the two boom parts 70, 80 to be nested for transport are connected in the operating position to staggered boom upper belts A, A '. Both cantilever segments 70, 80 are constructed mirror-inverted, i. the hypotenuse is formed at the cantilever tip 70 by the distance A'-C, whereas at the cantilever portion 80 the distance A-B represents the hypotenuse.

The horizontal offset of the upper belts A, A 'during crane operation is illustrated in FIGS. 7a, 7b and 8a, 8b. Figure 7a shows the crane boom according to the invention in a perspective side view during the operating position and Figure 7b shows a perspective side view of the boom in the transport position. Figures 8a, 8b show the figures 7a, 7b associated cross-sectional views of the crane jib in the region of the pivot axis 00th

The arrangement of the horizontal pivot axis 100 can be arranged depending on the desired height reduction between half the system height of the boom 80 and the plane of the upper flange A. As a result, the boom parts 70, 80 can be positioned with reduced height relative to each other only by pivoting about the axis 100 for transport in the sense of the invention.

Figures 9, 10 and 11 show an alternative embodiment of the crane boom according to the invention. Unlike in the embodiment according to the invention according to FIGS. 2, 4 and 6 to 8, no right-angled triangular shape is selected, but an intermediate shape between an isosceles and right-angled or nearly right-angled triangle is selected. The angle ratio of the angles .alpha. And .beta. In the lower chords is adjusted in such a way that the upper chord A lies outside, ie it does not lie on the side bisector of the triangle side BC. In the embodiment of Figure 9, the angles are selected according to the following rule a <β <90 °.

The greater the angular difference between the angles α and β is chosen, the greater the space saving during crane transport or during disassembly of a fast-erecting crane. Alternatively, the angle α can be dimensioned larger than the angle ß.

FIGS. 10, 11 show the alternative boom embodiment according to FIG. 9 during the road transport analogous to FIG. 4 and in the folded state analogous to FIG. 6. This alternative embodiment leads to a not quite optimal space utilization, in particular with regard to the resulting height dimension, during the transport state, however This cross-sectional shape may be sufficient for many applications, since still a satisfactory gain in space over the known from the prior art solution is possible. Furthermore, the proposed solution may have constructive advantages in terms of boom statics over the right triangular shape.

Claims

Patent claims

Crane boom for a crane consisting of an upper chord and two lower chords, which are connected to each other by means of a lattice and form a triangular boom cross section,

characterized,

that the boom cross section comprises, at least in sections, a triangular cross-sectional shape with an off-center top flange.

Crane boom according to claim 1, characterized in that the triangular cross section is at least partially rectangular or almost rectangular.

Crane boom according to one of the preceding claims, characterized in that the longest triangular side of the boom cross section, in particular whose hypotenuse connects the upper chord with a lower chord of the crane boom.

4. Crane boom according to one of the preceding claims, characterized in that the boom consists of two or more boom pieces that can be dismantled for road transport.

5. Crane boom according to one of the preceding claims, characterized in that at least two boom areas are mounted so that they can pivot relative to one another about a pivot axis, in particular a horizontal pivot axis.

6. Crane boom according to claim 5, characterized in that the at least two boom areas can be pivoted through 180 ° to one another, whereby the boom areas, in particular their longest triangular side or hypotenuses, can be placed sideways against one another for crane transport.

7. Crane boom according to one of the preceding claims, characterized in that the upper chords of the at least two boom areas are laterally offset from one another.

8. Crane boom according to one of claims 5 to 7, characterized in that the pivot axis is arranged in a region between half the system height of the boom and the plane of the upper chord.

9. Crane boom according to one of the preceding claims, characterized in that the boom comprises at least one boom area with a boom cross section forming an isosceles triangle, wherein boom sections with different boom cross sections are optionally connected to one another by means of a transition piece.

10. Crane boom according to one of the preceding claims, characterized in that the lower chords form a trolley track.

1 . Crane, in particular a quick-erecting crane or top-slewing crane, with a crane boom according to one of claims 1 to 10.