CRANE

Description

[0001] The present invention relates to a crane, in particular in the form of a tower crane, with a boom and a counter boom which are articulated to a boom pivot point, wherein the boom comprises an outer boom part which is pivotally connected to an inner boom part and held by a bracing.

[0002] To lift heavy loads on tower cranes with relatively large jibs (i.e., long boom lengths), it is common practice to guy the boom. Typically, one, two, or even three guy wires or bars are run from a tower top extending above the boom and attached to the boom. Depending on the boom length, the attachment points of the guy wires or bars can be located approximately in the middle of the boom, or in an inner third and / or an outer third. "Inner" refers to a boom section closer to the tower, while "outer" refers to a boom section that extends further out and is further away from the tower. For example, a first guy wire might be attached at about one-third of the total boom length, and a second guy wire at about two-thirds.

[0003] The "total" boom length refers to the boom without the counter boom, i.e., the part of the boom along which the trolley travels.

[0004] If a counter jib is present to support the ballast weight, the guying is usually also routed to the rear of this counter jib. On tower cranes without a counter jib, the guying is routed downwards via the rearward-leaning tower top or guy wire.

[0005] More recently, tower cranes that forgo such jib bracing have also become popular. Instead, the jib itself is reinforced to such an extent that it can absorb the forces as a flexed-beam jib. These topless tower cranes are sometimes called "flat-top" cranes or "hammerhead" cranes because they lack the tower top that extends above the jib. Key advantages of such topless tower cranes are essentially their lower overall height and a simpler assembly process.

[0006] Document EP 2 041 017 B1 describes such a topless tower crane and proposes an assembly method intended to facilitate its construction. Document DE 10 2005 018 522 B4 also describes such a topless tower crane, in which the entirely bracing-free jib is designed to have multiple bearing points to allow it to be mounted at different locations on the top of the tower, thus enabling the counter jib to have varying lengths. Another topless tower crane is described, for example, in document GB 14 93 715 or in the brochure "The EC-B Flat-Top Cranes" published by Liebherr-Werk Biberach GmbH.

[0007] A comparison between a guyed tower crane with a tower top and a flat top crane without a top is shown in document ES 22 64 334 A1. It proposes mounting the counter jib slightly higher than the jib to further simplify assembly.

[0008] Document SU 1 082 749 A1 discloses a tower crane according to the preamble of claim 1, on the tower of which a beam projecting symmetrically to both sides is attached, to the projecting ends of which a jib and a counter-jib are articulated. From an articulated guy wire, guy wires extend on one side to the articulated jib and the articulated counter-jib, and on the other side to the projecting ends of the beam symmetrically attached to the tower.

[0009] Further bracing for the booms of tower cranes is known from the documents CN 203 820 334 U and CN 2 261 415 Y.

[0010] Tower cranes with relatively short boom bracing are known, for example, from the Spanish company JASO under the type designation H-series, such as model variant J560. In these cranes, the boom is relatively massive up to the boom tip to absorb the bending forces and moments, which makes the crane relatively heavy and robust overall.

[0011] A general disadvantage of tower cranes without a top is that the high jib bending moments necessitate heavy components and jib sections with dimensions that are difficult to transport, especially for large cranes > 300 mt. To counteract these high jib bending moments, particularly in the inner jib section closest to the tower, these inner jib sections require a large jib height and massively dimensioned longitudinal chords.

[0012] Based on this, the present invention aims to create an improved crane of the type mentioned above, which avoids disadvantages of the prior art and advantageously develops the latter further. In particular, simpler assembly of the boom and the crane's bracing is to be achieved, especially by reducing the assembly weights, without having to accept any static disadvantages with regard to load-bearing capacity.

[0013] According to the invention, the aforementioned problem is solved by a crane according to claim 1. Preferred embodiments of the invention are the subject of the dependent claims.

[0014] It is therefore proposed to combine an articulated guyed boom with a bending beam boom and to construct the boom from two differently designed and differently supported boom sections. According to the invention, the inner boom section is designed as a bending beam, which is rigidly attached and held to the boom pivot point, while the outer boom section is pivotally connected to the bending beam and held by a guy wire. This hybrid design of the boom significantly simplifies the crane assembly. Firstly, the assembly effort for the inner boom section is considerably reduced, since the bending beam only needs to be attached to the pivot point and is thus already held securely.On the other hand, the effort required for attaching the guy wires is also reduced, since, compared to the usual double-guyed boom designs, only the outer boom section needs to be guyed, and the guying block of conventional guying systems can potentially be omitted. Furthermore, the assembly weight is also reduced, especially if the central section, or the pivot point, is designed in two parts. Finally, a statically determinate system is achieved.

[0015] The inner boom section remains completely unbraced and is held solely by the rigid connection to the boom section, so that the bracing only goes to the outer boom section and only the outer boom section is braced.

[0016] To effectively absorb and dissipate the different stresses, a further development of the invention may require the inner and outer boom sections to be designed differently with regard to their structure or profile. Advantageously, the inner boom section, which is designed as a bending beam, can comprise more longitudinal chords than the outer boom section. For example, the inner boom section can be constructed from four longitudinal chords, while the outer boom section is formed from only three longitudinal chords, so that the inner boom section has a rectangular or trapezoidal profile, while the outer boom section can have a triangular profile in cross-section.

[0017] Regardless of the number of longitudinal chords, both the inner and outer cantilever sections can be designed as truss structures in which longitudinal chords are rigidly connected to each other by transverse chords or struts.

[0018] Advantageously, the boom is designed as a trolley boom. In particular, the inner boom section and the outer boom section – regardless of their respective number of longitudinal chords – can have two longitudinal chords that maintain a constant distance along the boom length and / or form a continuous track across the interface between the inner and outer boom sections.

[0019] The boom sections differ in height – viewed in profile or cross-section – with the cross-sectional profile of the outer boom section being smaller than that of the inner boom section. If the inner boom section does not have a constant profile height along its length, for example, because a boom section with a decreasing and / or reduced profile height is provided at its outer end, at least one inner section of the inner boom section – i.e., a section of the inner boom section arranged with and / or attached to the pivot point – has a profile cross-sectional height greater than the maximum profile cross-sectional height of the outer boom section.

[0020] The bracing for the outer boom section can be designed in different ways, and it is advantageous to be able to provide different bracing variants for different boom lengths and / or load capacities.

[0021] In an advantageous embodiment of the invention, the bracing for the outer boom section can be designed as a single strand. In such a single-strand design, two parallel bracing cables or rods can also be provided, which can be attached to the outer boom section at the same distance from the pivot point. In particular, however, only a single bracing cable or rod can be led to the outer boom section.

[0022] The aforementioned bracing can be guided from the outer boom section inwards over the inner boom section in various ways and can optionally be attached directly to the pivot point to which the inner boom section, designed as a bending beam, is also attached, or be led to a bracing tip that is placed on the aforementioned pivot point.

[0023] In order to be able to configure the bracing variably, an advantageous further development can provide a detachable connection between the aforementioned boom tip and the pivot piece, so that different, in particular different height, bracing tips can be placed on the pivot piece, to which the inner boom part is rigidly attached, depending on how the bracing is to be routed back inwards from the outer boom part.

[0024] For example, the bracing from a bracing tip to the outer boom section can run at a consistently acute angle to the longitudinal axis of the boom and / or a bracing support or bracing block between the two pivot points of the bracing on the outer boom section on the one hand and on the bracing tip at the pivot point on the other hand can be omitted, so that the bracing is freely supported between the outer boom section and the bracing tip.

[0025] Alternatively, a shorter guy wire can be mounted on the pivot point and / or the guy wire can be guided over a guy wire support, so that the guy wire runs essentially or at least approximately parallel to the longitudinal axis of the inner boom section. In this case, the guy wire rises from its pivot point on the outer boom section at an acute angle towards the inner boom section until it meets the aforementioned guy wire support, at which point it runs inwards from the guy wire support approximately parallel to the longitudinal axis of the inner boom section.

[0026] The aforementioned bracing support can, in principle, be attached at various points on the boom, for example, in the area of ​​the inner boom section designed as a bending beam. In particular, it can be advantageous if the aforementioned bracing support is attached approximately in the area of ​​the interface between the inner and outer boom sections.

[0027] The aforementioned guy wire can extend beyond the maximum height of the inner boom section or its profile, for example, by an amount that approximately corresponds to the height of the inner boom section's profile. Depending on the boom's geometry and structure, other guy wire heights may also be appropriate.

[0028] As an alternative to running the bracing parallel to the inner boom section, the bracing can also be configured to slope downwards towards the pivot point and / or, in particular, can be led directly to the pivot point itself, to which the inner bending beam section of the boom is also attached. In particular, a bracing tip on the pivot point can be omitted entirely, in which case the bracing for the outer boom section leads directly to the pivot point.

[0029] The detachable connection between the guy wire and the pivot point allows for the simple implementation of various guying configurations. For example, a detachable bolt connection can be used as the connecting element between the guy wire and the boom pivot point. Advantageously, the detachable connecting elements between the pivot point and the guy wire are rigidly designed to ensure a secure, rigid connection between the guy wire and the pivot point.

[0030] Advantageously, in a further development of the invention, the counter boom can also be configured differently and / or adapted to the respective boom configuration. In particular, the aforementioned counter boom and / or a counter boom bracing can be adapted to the bracing of the boom and / or the bracing tip used and / or an unused bracing tip.

[0031] The aforementioned counter boom can advantageously also be designed as a hybrid boom and include an inner counter boom section, which can be designed as a bending beam that can be rigidly attached to the pivot point to which the boom is also attached.

[0032] Furthermore, the counter boom can include an outer counter boom section that is pivotally connected to the inner counter boom section and held in place by a counter boom bracing. This outer counter boom section can support the ballast weight and / or carry other functional components, such as the hoist winch for the hoist cable.

[0033] The counter boom bracing, which holds the outer part of the counter boom, can be adapted to the bracing of the boom and, at its inner end, can advantageously be attached where the bracing of the boom is also attached.

[0034] If a guy wire is provided on the pivot point, the counter boom bracing is advantageously attached to said guy wire. Depending on the height of the guy wire, the counter boom bracing can be routed back inwards from its pivot point on the outer counter boom section in various ways.

[0035] Advantageously, the counter boom bracing can be guided by a bracing support that extends above the maximum height of the inner counter boom section. Regardless of this, such a bracing support for the counter boom bracing can be located at various points, for example, in the area of ​​the inner counter boom section. In particular, the aforementioned counter boom bracing support can be located at the interface between the inner and outer counter boom sections.

[0036] Advantageously, the counter boom guy support can rise significantly above the counter boom in height and, for example, be designed to be comparable in height to the guy tip that is attached to the pivot piece, so that the counter boom guying has an approximately horizontal course in the area between the guy support and the guy tip.

[0037] The guy wire used on the counter boom can therefore advantageously be adjusted in height to the guy wire tip used.

[0038] Alternatively, the counter boom bracing can also be attached to the inner counter boom section, which is designed as a bending beam, in particular to an upper longitudinal chord of the inner counter boom section or to a bracing linkage section connected to it.

[0039] The invention is explained in more detail below with reference to a preferred embodiment and the accompanying drawings. The drawings show: Fig. 1 a side view of a crane in the form of a tower crane of an advantageous embodiment of the invention, Fig. 2 a side view of the boom of the crane made of Fig. 1 , which shows the inner boom section designed as a bending beam and the outer, braced boom section, with partial views A, B and C showing different bracing variants of the outer boom section with bracing tips of varying heights and without bracing tips, Fig. 3 a side view of the counter boom of the crane made of Fig. 1 , where partial views X, Y and Z show different bracing variants of the counter boom bracing.

[0040] As the figures show, crane 1 can be designed as a tower crane, comprising an upright tower 2. This tower 2 can be designed as a truss structure and, for example, have a rectangular cross-section.

[0041] A boom 3 is hinged to the upper end of tower 2, which is usually horizontal, in particular approximately horizontal. A counter boom 4 can be provided on the side of tower 2 opposite boom 3; this counter boom 4 can also be horizontal, in particular horizontal, and can carry a ballast weight 5.

[0042] A trolley 6 can be arranged longitudinally on the boom 3 in a manner known per se, in order to lower and raise the hoist cable 7 and the associated load hook closer to or further away from the tower 2. Advantageously, the hoist cable 7 can be lowered and raised by means of a hoist 16, which can be arranged on the counter boom 4 in the vicinity of the ballast weight 5.

[0043] How Fig.1 As shown, both the boom 3 and the counter boom 4 can be attached to a pivot point 8, which can be mounted or arranged at the upper end of the tower 2. If the crane is a top-slewing crane, the pivot point 8 can be mounted on the bearing ring of a slewing mechanism. If the crane is a bottom-slewing crane, the pivot point 8 can be rigidly connected to the tower 2 and / or form its uppermost section.

[0044] A guying point 9 can also be seated on the aforementioned pivot piece 8, to which the guyings for the boom 3 and the counter boom 4 can be attached, as will be explained in more detail below.

[0045] How Fig. 2 As shown, the boom 3 comprises an inner boom section 3i and an outer boom section 3a, which is hinged to the outer end of the inner boom section 3i. "Inner" and "outer" refer to the projection and distance from the tower 2, respectively. The inner boom section 3i is closer to the tower 2 than the outer boom section 3a.

[0046] How Fig. 2 As shown, the inner cantilever section 3i is designed as a bending beam, which is rigidly and securely attached to the aforementioned pivot point 8, for example by a bolting or other positive-locking connection of the upper and lower chords of the inner cantilever section 3i to the aforementioned pivot point 8. If the inner cantilever section 3i is pulled downwards or loaded by the trolley 6 or by its own weight, the upper chord(s) are subjected to tension and the lower chord(s) to compression, whereby the bending moment is introduced into the pivot point 8 or absorbed by the pivot point 8.

[0047] How Fig. 1 As shown, the inner cantilever section 3i, designed as a bending beam, can remain free of bracing.

[0048] The guy wire 10 can hold the outer boom section 3a on its own or can only be led to the outer boom section 3a, which is held by the aforementioned guy wire 10.

[0049] How Fig. 2 As shown, both the inner and outer cantilever sections 3i and 3a can each be designed as truss girders and / or be composed of several cantilever sections. Such a truss design can, in particular, consist of longitudinally extending upper and lower chords being rigidly connected to each other by transverse struts, thus forming a rigid truss structure.

[0050] The lower belts can form tracks for the trolley 6.

[0051] The inner and outer boom sections 3i and 3a can be designed differently. In particular, the inner boom section 3i can have a larger cross-sectional area and / or more longitudinal chords than the outer boom section 3a. For example, the boom sections of the inner boom section 3i can each have four longitudinal chords, while the boom sections of the outer boom section can have only three longitudinal chords. The inner boom section can have a rectangular or trapezoidal cross-sectional area with two upper chords and two lower chords, while the outer boom section can have a triangular cross-sectional area with one upper chord and two lower chords.

[0052] How Fig. 2 As shown, the bracing 10 for the boom 3 can be designed as a single strand.

[0053] According to training variant A of the Fig. 2 The guying 10 can be led directly from the outer boom section 3a to the guying tip 9 without intermediate guying supports.

[0054] Alternatively, the bracing 10 can also be guided via a bracing support 11, which projects above the top of the boom 3 between the two attachment points of the bracing 10. Such a bracing support 11 can, for example, be arranged in the area of ​​the joint 15 between the inner and outer boom sections 3 and, for example, be attached to the projecting end 12 of the inner boom section 3, which is designed as a bending beam. In principle, however, it would also be possible to arrange the aforementioned bracing support 11 further inwards towards the tower 2 or further outwards on the outer boom section 3a.

[0055] If such a guy wire support 11 is provided, the guy wire tip 9 provided on the tower 2 can have a lower height, as shown in partial view B of the Fig. 2 shows. In particular, the guy wire support 11 and the guy wire tip 9 can rise essentially the same distance above the boom 3, so that the guy wire 10 can run approximately parallel to the longitudinal axis of the boom 3, more precisely, of the inner boom section 3i, and only dips outwards from the guy wire support 11 at an acute angle to the outer boom section 3a, cf. Fig. 2B .

[0056] Furthermore, it is possible, as shown in partial view C of the Fig. 2 This shows that the guy wire tip 9 can be omitted entirely and the guy wire 10 can be attached directly to the pivot point 8. In this case, the guy wire 10 descends from the guy wire support 11 inwards towards the tower 2 at an acute angle to the longitudinal axis of the boom 3.

[0057] To facilitate the provision and interchangeability of different guying configurations, the guying tip 9 and the connecting piece 8 can advantageously be designed separately and detachably connected. For example, the guying tip 9 can be rigidly connected or locked to the connecting piece 8, for instance, by a bolted connection or a similar positive-locking connection. Once the bolts or connecting elements are loosened, the guying tip 9 can be removed and replaced with another guying tip or eliminated entirely.

[0058] How Fig. 3 As shown, the counter boom 4 can also have an inner counter boom section 4i, which is designed as a bending beam and can be rigidly attached to the pivot piece 8, for example by a rigid connection, such as a bolted connection of the upper and lower chords of the inner counter boom section 4i to the aforementioned pivot piece 8.

[0059] The inner counter-cantilever section 4i can also be designed as a truss girder with upper and lower chords, cf. Fig. 3 .

[0060] An outer counter boom section 4a can be articulated to the aforementioned inner counter boom section 4i and held by a counter boom bracing 13.

[0061] The aforementioned counter-jib bracing 13 can also be single-strand, although a multi-strand counter-jib bracing would also be possible.

[0062] How Fig. 3 As shown, the counter boom bracing 13 can extend from an outer end section of the counter boom 4 to the bracing tip 9, to which the bracing 10 for the booms 3 is also attached. The counter boom bracing 13 can advantageously be guided via a bracing support 14, which is provided, for example, in the area of ​​the hinge 15 between the inner and outer counter boom sections 4i and 4a, although it would also be possible to position the bracing support 14 further outwards or further inwards. As shown in Figs. 3a and 3b, the aforementioned bracing support 14 can, in particular, be hinged to the outer end section of the inner counter boom section 4i.

[0063] The aforementioned guying support 14 can be adjusted in height above the counter boom 4 to the height of the guying tip 9, in particular such that the counter boom guying 13 is guided approximately horizontally and / or parallel to the longitudinal axis of the inner counter boom part 4i.

[0064] As Fig. 3c shows, the counter-jib bracing 13 can also be attached directly to the inner counter-jib part 4i, which is designed as a bending beam, in particular to the upper chord of the inner counter-jib part 4i or a bracing beam connected to it.

[0065] The design of the counter-jib bracing 13 according to partial views A and B of the Fig. 3 match the design of the bracing 10 of the boom 3, as shown in partial views A and B of the Fig. 2 shown.

[0066] The variant of the counter-jib bracing 13 according to partial view C of the Fig. 3 However, it can be used for all variants or regardless of the design of the bracing 10 of the boom 3, i.e., the counter boom bracing 13 according to Fig. 3c fits all variants as shown by the Fig. 2 in their partial views A, B and C.

[0067] The bracing options for the outer boom section 3a, as they Fig. 2 As shown in its various partial views, suitable options can be selected for different variants, projections, and / or load capacities of the boom 3. For shorter booms 3, the bracing 10 can potentially be omitted entirely, and the outer boom section 3a can be rigidly attached to the inner boom section 3i, in particular by positively interlocking the upper chords.

[0068] The ratio of the lengths of the inner boom section 3i and the outer boom section 3a can generally be chosen differently, whereby generally favorable conditions result if the length of the inner boom section is in the range of 25% to 75% or 30% to 60% or 35% to 50% of the total length of the boom and the length of the outer boom section 3a is 75% to 25% or 70% to 40% or 65% to 50% of the total length of the boom 3.

Claims

1. A crane, in particular a revolving tower crane, having a boom (3) and a counterboom (4) that are connected in an articulated manner to an articulation piece (8), wherein the boom (3) comprises an outer boom part (3a) that is pivotally connected in an articulated manner to an inner boom part (3i) and is held by a guying (10), wherein the inner boom part (3i) is configured as a bending beam that is flexurally rigidly fastened to the articulation piece (8); wherein the inner boom part (3i) is held without guying and the boom (3) is only guyed at the outer boom part (3a), characterized in that the inner boom part (3i) has a profile cross-sectional height that is larger than a maximum profile cross-sectional height of the outer boom part (3a) and / or has a profile cross-sectional area that is larger than the maximum profile cross-sectional area of the outer boom part (3a).

2. A crane in accordance with the preceding claim, wherein the inner boom part (3i) comprises more longitudinal webs than the outer boom part (3a), in particular with the inner boom part (3i) having four longitudinal webs and one rectangular or trapezoidal profile cross-section and the outer boom part (3a) having three longitudinal webs and one triangular profile cross-section.

3. A crane in accordance with one of the preceding claims, wherein the guying (10) of the boom (3) is configured as a single strand..

4. A crane in accordance with one of the preceding claims, wherein a guying tip (9) is preferably releasably fastened to the articulation piece (8) to which guying tip (9) the guying (10) for the outer boom part (3a) is lashed.

5. A crane in accordance with the preceding claim, wherein different guying tips having different heights can be placed on and rigidly fastened to said articulation piece (8).

6. A crane in accordance with one of the preceding claims, wherein the guying (10) is guided continuously free of support from the outer boom part (3a) at an acute angle over the inner boom part (3i) increasing toward the guying tip (9).

7. A crane in accordance with one of the preceding claims, wherein the guying (10) is guided from the outer boom part (3a) over a guying support (8) and is connected in an articulated manner at an inner articulation point (10) via or at the articulation piece (8).

8. A crane in accordance with the preceding claim, wherein the guying (10) is guided from said guying tip (11) approximately in parallel with the longitudinal axis of the inner boom part (3i) inwardly to the / a guying tip (9) seated on the articulation piece (8).

9. A crane in accordance with claim 8, wherein the guying (10) is guided inwardly from said guying support (11), falling toward the articulation piece (8), at an acute angle to the longitudinal axis of the inner boom part (3i) and is lashed to the articulation piece (8).

10. A crane in accordance with one of the preceding claims 8 to 10, wherein the guying support (11) is arranged in the region of the joint between the inner and outer boom parts (3i, 3a) and projects over the inner boom part (3i) by a height that is in the range from 25% to 200% or 50% to 200% or 75% to 150% of the height of the profile of the inner boom part (3i).

11. A crane in accordance with one of the preceding claims, wherein the counterboom (4) comprises an inner counterboom part (4i) that is configured as a bending beam that is flexurally rigidly fastened to the articulation piece (8).

12. A crane in accordance with the preceding claim, wherein the counterboom (4) comprises an outer counterboom part (4a) that is pivotally connected in an articulated manner to said inner counterboom part (4i) and is held by a counterboom guying (13) that is lashed to the guying tip (9) to which the guying (10) for the boom (3) is also lashed, with the inner counterboom part (4i) being held free of guying.

13. A crane in accordance with the preceding claim, wherein the counterboom guying (13) is guided over a guying support (14) whose height at least approximately corresponds to the height of the guying tip (9) so that the counterboom guying (13) extends at least approximately horizontally between the guying support (14) and the guying tip (9).

14. A crane in accordance with one of the preceding claims, wherein the counterboom guying (13) is lashed to the inner counterboom part (4i).