MOBILE CRANE WITH TWO-PART JIB, AND METHOD FOR ALIGNING THE BOOM SYSTEM OF SUCH A MOBILE CRANE

Abstract

The invention relates to a mobile crane with a two-part jib and to a method for aligning the boom system of such a mobile crane. The invention relates to a mobile crane with a multi-part flight boom, wherein a first jib part is hinged to the main boom in a rockable manner, and at least one second jib part is secured to the first jib part in an articulated manner. A bracing which is guided from the upper chassis to the jib is provided for aligning the jib, said bracing running over at least one intermediate bracing support mounted on the first jib part to the at least one second jib part.

Claims

1. A mobile crane having a multi-part fly boom, wherein a first fly boom part is luffably connected to a main boom in an articulated manner and at least one second fly boom part is fastened to the first fly boom part in the articulated manner, and a guying guided from a superstructure up to the fly boom is provided for raising the fly boom, wherein the guying extends over at least one intermediate guying frame installed at the first fly boom part up to the at least one second fly boom part.

2. A mobile crane in accordance with claim 1, wherein the intermediate guying frame is fastened to the fly boom part with torque rigidity.

3. A mobile crane in accordance with claim 1, wherein the intermediate guying frame is connected to the fly boom in the articulated manner and is alignable or aligned in a torque-rigid manner via at least one separate frame guying or an abutment.

4. A mobile crane in accordance with claim 3, wherein the intermediate guying frame and the separate frame guying form a double crank that is fastened to the first fly boom part.

5. A mobile crane in accordance with claim 1, wherein the intermediate guying frame is installed at the first fly boom part in a region of a join for at least one fly boom part, in particular top flange of the fly boom part.

6. A mobile crane in accordance with one claim 3, wherein the guying frame and, optionally, the separate frame guying comprise an adjustment means for setting a guying frame length or guying length.

7. A mobile crane in accordance with claim 6, wherein the adjustment means comprises a telescopic mechanism.

8. A mobile crane in accordance with claim 1, wherein the guying is fastened to a head or to a head region of a second fly boom element.

9. A mobile crane in accordance with claim 3, wherein the guying and/or the frame guying is/are bolted to a free end of the guying frame.

10. A mobile crane in accordance with claim 1, wherein the intermediate guying frame can be moved into a transport position for a crane transport, and an intermediate frame can in particular be folded onto the fly boom for transport purposes.

11. A mobile crane in accordance with claim 8, wherein a latching device is provided at a connection point of fly boom parts that ensures an automatic latching during a raising procedure, the latching device is provided at the second fly boom part and ideally comprises a pivotable latch that automatically engages around a bolt of the first fly boom part.

12. A method of raising a boom system in a mobile crane in accordance with claim 11 comprising these steps: a. Assembly of the first fly boom part, including raising frames at the main boom, the guying, and the intermediate guying frame at the first fly boom part; b. luffing of the main boom and assembly of additional guying or guying bars; c. minimal luffing of the fly boom and assembly of the at least one second fly boom part and fastening of the additional guying to the head part of the fly boom; and d. luffing the fly boom up to a geometrical closing of a latch connection between the fly boom parts.

13. A method in accordance with claim 12, wherein the head of the fly boom is guided on ground on at least one trolley or roller during the raising procedure.

14. A method in accordance with claim 12, wherein, after the luffing up of the main boom, the intermediate guying frame installed in the articulated manner is luffed up and an optional frame guying is installed to ensure a required torque rigidity of the intermediate guying frame.

Description

[0026] Further advantages and properties of the invention will be explained in more detail in the following with reference to an embodiment shown in the Figures. There are shown:

[0027] FIG. 1: a sketched side view of a conventional mobile crane having a foldable fly boom;

[0028] FIG. 2: a sketched side view of the mobile crane in accordance with the invention with an installed intermediate guying frame and a completely raised or installed fly boom;

[0029] FIG. 3: a detail view of the join between the fly boom parts, including the intermediate guying frame;

[0030] FIG. 4: a detail view of the latching device for the join between the fly boom parts; and

[0031] FIGS. 5a-5f: a chronological sequence of the raising process for the fly boom of the mobile crane in accordance with the invention.

[0032] FIG. 2 shows a sketch of the mobile crane in accordance with the invention having a foldable fly boom 30. In a similar manner to the prior art, the mobile crane comprises a vehicle 10 and the telescopic boom 20 that is luffably installed at the vehicle 10 and that can be luffed up by luffing rams, not shown. The fly boom 30, that is in turn composed of the two fly boom parts 30a, 30b, is luffably installed at the head end of the telescopic boom 20.

[0033] The articulated connection between the fly boom parts 30a, 30b is marked by reference numeral 32. The intermediate guying frame 40, that is arranged in the end region of the first fly boom part 30a and that is additionally fixed in a torque-rigid manner to the first fly boom part 30a, can be recognized in the end region of the first fly boo part 30a. The guying 50 extends from the superstructure of the vehicle 10 along the main boom 20 over the raising frames 51 up to the intermediate guying frame 40. The guying 50 partly comprises stay poles, in particular in the region 50 between the raising frames 51 up to the intermediate guying frame 40 where they are fixedly bolted to the free end of the intermediate guying frame 40. In accordance with the invention, the guying 50 is extended from the intermediate guying frame 40 by the section 52 up to the head end of the fly boom part 30b and is there fixedly connected, in particular bolted, thereto. A complete guying of the fly boom 30 is thereby achieved in regular crane operation. A guyed boom system without a cantilever effectively results. The effect of the side stabilization by the guying up to the head of the fly boom to can be used, particularly with long fly booms, due to the torque-rigid intermediate guying frame 40.

[0034] The guying 50 can still be used to raise the fly boom 30 despite the extended guying 52 up to the free end of the fly boom 30. Accordingly, no additional actuators or drives within the guying are required. The intermediate guying frame 40 required for this purpose is formed by a bar that is rigid in compression and is configured either with torque rigidity at the rear fly boom part 30a of the boom 30 oras shown in detail in FIG. 3is installed in an articulated manner at the fly boom part 30a. An additional guying 41 is provided between the intermediate guying frame 40 and the fly boom part 30a to ensure the required torque rigidity. The double crank thereby formed prevents an unwanted folding over of the intermediate guying frame 40 to the rear in the direction of the telescopic boom 20 on an exertion of force on the guying 50. Alternatively, instead of the guying 50, a support could also be installed that is fastened to the fly boom part 30a on the other side of the intermediate guying frame 40, that is closer to the telescopic boom 20.

[0035] The specific design of the double crank can be seen from the detailed illustration in FIG. 3 that is formed by the intermediate guying frame 40 having compressive rigidity and fastened in an articulated manner to the first fly boom part 30 and the additional linkage 41. A folding down of the intermediate stay pole 40 to the rear in the direction of the telescopic boom 20 is thereby prevented due to the geometry. The stay pole 50, that starts from the raising frame 51 and that is bolted to the stay pole 40 at the end side, is equally recognizable in the detailed illustration of FIG. 3. The same applies to the additional stay pole 52 that is bolted to the intermediate stay pole 40, on the one hand, and to the most extreme end of the second fly boom part 30b, on the other hand.

[0036] The pivot joint 32 between the two fly boom parts 30a, 30b and the mount 31 for the reception of the matching counterpart at the first fly boom part 30a can equally be seen from the detailed illustration.

[0037] To raise the fly boom 30, the guying winch at the superstructure of the vehicle 11 is wound up, whereby the rope arrangement disposed between the first raising frame 51 and the guying winch is shortened. The tension thereby applied is transmitted from the raising frames 51 up to the intermediate guying frame 40 to the first fly boom part 30a, whereby the latter is upwardly pivotable about a horizontal axis with respect to the main boom 20. The front part 30b having the still non-guyed guying 52 dan, as with the previous cantilever system, fold down until the joins 31 engage into one another and the latching device latches. When a load is suspended, new conditions are adopted that lead off some of the forces over the guying 50 at the head of the front part 30b. For this purpose, the length ratios of the guying 50 and of the lattice pieces of the fly boom 30 have to be coordinated with one another. Only in this way can a distribution of the forces and torques be achieved that is as good as possible.

[0038] The latching device can be seen in detail from FIG. 4. The first fly boom part 30a and the second fly boom part 30b can be seen here. The latter carries the latching device having the latch 36 that is pivotably supported at the fly boom part 30b by means of a pivot joint 37. On the closing of the join 31 between the fly boom parts 30a, 30b, the latch 36 pivots up and engages around the bolt 38 of the first fly boom part 30a, whereby the join 31 is additionally secured against tension forces. A sensor system 39 detects the latch state and reports it to the crane control.

[0039] To ideally support a spectrum of conceivable fly boom conditions that is as wide as possible with the intermediate guying frame 40, this frame 40 can be adjustable in length. This can be implemented, for example, by pipes that are guided into one another and that can be bolted to one another at different positions. An adaptation of the length of the guying 41 between the intermediate guying frame 40 and the fly boom part 30a is equally optionally required. The most varied configurations of the fly boom 30, in particular different combinations of standard lattice pieces, can thereby be ideally used simply and without any additional parts or only minimally more parts.

[0040] The progression of the raising procedure of the boom system of the mobile crane in accordance with the invention will be briefly explained with reference to the illustrations of FIGS. 5a-5f: that reproduce the individual method steps chronologically.

[0041] In the first step, the assembly of the first fly boom part 30a at the main boom 20 takes place close to the ground. The head of the first fly boom part is supported either on rollers or on a trolley 70 in this process. At the same time, he attachment of the intermediate guying frame 40 to the first fly boom part 30a can take place and the stay poles 50 can be installed. This is shown in FIG. 5a.

[0042] In the second method step in accordance with FIG. 5b, the telescopic boom 20 is first luffed up by means of the luffing ram and the frame guying 41 and the extended guying region 52 can be assembled starting from the intermediate guying frame 40 in the direction of the not yet assembled second fly boom part 30b.

[0043] In the next step, the intermediate guying frame 40 can be luffed up and can be luffed up into the required position perpendicular or almost perpendicular to the longitudinal axis of the fly boom 30a. The separate frame guying 41 is then suspended for the fixing of the intermediate guying frame 40 (FIG. 5c).

[0044] In the next step in accordance with FIG. 5d, the first fly boom part 30a is luffed up a little via the guying 50 to be able to assemble the second fly boom part 30b at the pivot point 32. The roller/trolley 71 then serves the support of the tip of the fly boom part 30b.

[0045] The assembly of the guying 52 at the head of the fly boom 30b then takes place. Work continues with the luffing up of the first fly boom part 30a (FIG. 5e) until the second fly boom part 30b lowers down due to gravity and the join 31 between the fly boom parts 30a, 30b is completely closed. This likewise comprises the latching of the latching device by pivoting the latch arm 36 inward. Finally, the assembled fly boom 30 is then fully luffed up (FIG. 5f).