EP3898492A1

EP3898492A1 - Assembly with a boom that can be luffed by two luffing cylinders, and correspondingly equipped vehicle crane

Info

Publication number: EP3898492A1
Application number: EP19832883.3A
Authority: EP
Inventors: Christian Moritz Urban
Original assignee: Tadano Demag GmbH
Current assignee: Tadano Demag GmbH
Priority date: 2018-12-21
Filing date: 2019-12-17
Publication date: 2021-10-27
Also published as: DE102018133493A1; JP2022516420A; US20220073321A1; WO2020127318A1

Abstract

The invention relates to an assembly (10) having a boom (4) that can be luffed between a storage position (P1) and a working position (P2) within a vertical luffing plane (WE) by at least two luffing cylinders (5a, 5b), the luffing cylinders (5a, 5b), which lie opposite one another on the luffing plane (WE), enclosing a spread angle (a) between their longitudinal axes (x1, x2) in the working position (P2), and the luffing cylinders (5a, 5b) acting on the boom (4) outside its ends. In order to achieve a design that is as compact as possible, particularly when the boom is in the storage position, according to the invention the longitudinal axis (x1, x2), projected onto the luffing plane (WE), of one luffing cylinder (5a, 5b) and a vertical direction (Z) extending within the luffing plane (WE) enclose an angle of inclination (b) therebetween when the boom (4) is in the storage position (P1).

Description

Arrangement with a boom that can be rocked over two luffing cylinders and

suitably equipped mobile crane

The invention relates to an arrangement with at least two luffing cylinders within a vertical luffing plane between a storage position and a working position luffing jib, the luffing cylinders lying opposite on the luffing plane in the working position enclosing a spreading angle between their longitudinal axes and the luffing cylinders attacking the jib outside of its ends. The invention also relates to a mobile crane with such a crane

Arrangement.

The performance of mobile mobile cranes required in operation is largely determined by their respective boom. Its mostly seesaw and

Telescopic arrangement on a rotating superstructure opens up correspondingly large work spaces within which the necessary transfer of loads can take place. The vertical alignment of the boom, which extends essentially horizontally in the process, between its storage position and a working position that is set up in relation thereto, takes place via at least one length-adjustable luffing cylinder.

From the British laid-open specification GB 843.024 A, a mobile crane with a boom emerges which has a total of two independently operating luffing cylinders. The mobile crane has an undercarriage on which the boom is supported in an articulated manner via its lower end. The luffing cylinders extending between the boom and the undercarriage are connected in an articulated manner to a region of the boom via their upper ends. The lower ends of the luffing cylinders are pivotally supported on the undercarriage in such a way that their longitudinal axes enclose an expansion angle between them. Because the two luffing cylinders can be controlled separately from one another, it is possible to pivot the boom within a vertical luffing plane and also to a limited extent horizontally relative to the undercarriage.

The A-shaped spread position of the two luffing cylinders relative to one another is based on the desire for a possibility for aligning the boom relative to the undercarriage of the mobile crane that goes beyond the vertical pivotability. Next the only limited lateral pivoting of the boom is due to its design in its storage position on the two in projection on the

Rocker plane vertically aligned rocker cylinders, which in particular during the process the advantage of the most compact vehicle dimensions

opposes. In view of these observations, the known arrangement still offers room for improvement.

From the patent US 2 996 196 is another mobile crane with a

Main boom and a luffing jib known. Here, the main boom consists of two main boom arms, which together at one upper end

Main boom head are mounted and extend from here in a V-shape towards the vehicle. With their lower ends, the two main boom arms are each mounted on the vehicle so that they can be rocked about horizontal axes. The

The main boom arms can be telescoped in opposite directions so that the main boom can be tilted to the left or right. For the bobbing of the two

The main boom arms are provided with a single telescopic luffing jib, which is also articulated to the main boom head and to a swivel frame on the vehicle. The two main boom arms and the luffing jib thus form a tripod starting from the main boom head. In connection with the luffing process of the two main boom arms, these are loaded under pressure and the luffing jib is subjected to tension. The U-shaped swivel frame is in turn articulated in the area of the horizontal axes of the main boom arms on the vehicle. In addition, the swivel frame can be swiveled from an erected operating position into a substantially horizontal transport position via a hydraulic cylinder, which is also supported on the vehicle. Together with the swivel frame, the two main boom arms with the luffing jib are thus moved from the other hydraulic cylinder from the operating position to the

Transport position swiveled.

Furthermore, utility model DE 20 2005 015 044 U1 already describes a mobile crane with an undercarriage which can be moved on the road and on which an upper carriage which is pivotable about a vertical pivot axis is mounted. A telescopic boom with a basic box and several inner boxes that can be telescoped from it are mounted on the superstructure so that they can be rocked about a horizontal axis. The telescopic cylinder is rocked up and down by means of two hydraulic rocking cylinders which are arranged in parallel and at a distance from one another and which are located at their lower ends support on the superstructure and are articulated with their upper ends approximately in the area of the center and on the underside of the basic box of the telescopic boom.

The present invention is therefore based on the object of the previously known arrangement and a vehicle crane equipped in this way

to further develop that, particularly in the storage position of the jib, the most compact possible design can be achieved.

This object is achieved according to the invention in an arrangement with the features of claim 1. In the dependent claims 2 to 14 and 16 advantageous embodiments of the invention are given. Furthermore, this object is achieved by a mobile crane with the features of claim 15.

According to the invention, the invention proposes that in the case of an arrangement with a jib that can be rocked over at least two luffing cylinders within a vertical luffing plane between a storage position and a working position, the luffing cylinders lying opposite one another on the luffing plane including a spreading angle between their longitudinal axes and the luffing cylinders on the Attack the boom outside of its ends, in the preferred horizontal storage position of the boom the longitudinal axis of a luffing cylinder projected onto the luffing plane and a vertical direction or vertical direction extending within the luffing plane shoot an inclination angle between them. In other words, the two luffing cylinders are inclined in a side view of the boom as a result of said vertical vertical direction as soon as the boom is in its

Storage position is.

In connection with the present invention, the feature with regard to the luffing cylinders that engage the boom outside its ends is understood to mean that the luffing cylinders engage an area on the boom or the basic box that extends in the longitudinal direction of the boom or one Basic set of the

Boom seen at least 10%, preferably at least 20%, particularly preferably at least 30%, of the total length of the boom or

Basic box is spaced from the upper and also the lower end of the boom or the basic box. All in all, the luffing cylinders act more centrally on the extension arm or the basic box than on the head end. The resulting advantage lies in the fact that the over

Boom cylinder-supported booms are no longer raised over their entire component length remaining in the retracted state as soon as it is in its storage position. Compared to the alignment of the luffing cylinders that was previously vertical or parallel to the vertical direction, in the now possible, approximately or exactly horizontal alignment of the luffing cylinders, significantly less installation space is now required below the boom in the storage position to

To be able to accommodate luffing cylinders. According to the invention, the alignment of each individual luffing cylinder, which is always inclined to the vertical direction in the storage position of the boom, ensures that the position of its end connections, which have hitherto been superimposed, is offset from one another due to the horizontal and vertical components resulting from the inclination. Since the upper end connection of each inclined luffing cylinder is pivoted in a circular path around its lower end connection, the boom can be aligned correspondingly lower in its storage position.

According to a preferred development of the basic concept of the invention, the tilt angle of the luffing cylinder in relation to the vertical direction can be from 60 ° to 120 ° in the storage position of the boom. This makes it possible for each luffing cylinder to extend not only up to + 30 ° above a horizontal, but also down to -30 ° below the horizontal position of the boom. Depending on the arrangement of the lower end connections of the luffing cylinders and the pivotable mounting, the boom in its storage position can also incline upwards or downwards with respect to the horizontal and extend parallel to it.

Depending on the configuration, it is considered advantageous if the luffing cylinders can extend almost parallel to the horizontal in the storage position of the boom, the angle of inclination of which relative to the vertical direction then being preferably from 80 ° to 100 ° or from 90 ° to 97 °.

The invention provides that the arrangement can comprise a base frame, on which the boom is rocked with its lower end. To one To obtain the most stable and self-contained arrangement possible, it is considered to be particularly advantageous if the rocker cylinders are also articulated on the base frame. For this purpose, lower bearing arrangements designed as universal joints or ball-and-socket joints, for example, can advantageously be provided, via which the rocker cylinders are correspondingly connected to the base frame.

As an alternative or in addition to this, the cantilever arm mounted on a base frame can comprise upper bearing arrangements, which are then each assigned to an upper end of one of the two Wpp cylinders. That way they are

Rocker cylinders are also articulated at their upper ends via the upper bearing arrangements on the boom. The upper bearing arrangements can preferably be designed as a universal or ball joint.

According to a particularly preferred embodiment of the invention, at least one of the bearing arrangements mentioned above can be relative to the base frame

or be movable to the boom in order to be positioned variably as required along an associated path that runs perpendicular to the wpp plane. For this purpose, said path can have a straight or curved course, at least in sections. The resulting displaceability of at least one of the two lower bearing arrangements and / or upper ones

Bearing arrangements enable a corresponding change in the spreading angle between the wrap cylinders, as a result of which the spreading angle enclosed between them can be opened downwards (A-shape) or upwards (V-shape). In other words, the two Wpp cylinders can have an A-shape or a V-shape with one another from a frontal view. In the case of said V-shape, the upper ends of the Wpp cylinders on the boom in the orthogonal direction to the luffing plane are further apart than their opposite lower ends on the base frame. The same applies vice versa for the A-shape. The V shape enables a more compact

Version close to the lower bearing arrangements of the luffing cylinders.

By means of said relocability of the lower and / or upper bearing arrangements, the position resulting from the A-shaped or V-shaped position, which stabilizes the arm in particular in its A-shape against lateral influences, can be obtained If necessary, increase the effect in an advantageous manner, for example. Regardless of this, the displacement of the bearing arrangement of at least one rocking cylinder enables even more compact dimensions of the arrangement according to the invention if required. Thus, the at least one bearing arrangement can preferably be shifted closer to the boom in the storage position by the lateral dimensions of the

At least temporarily reduce the arrangement accordingly. The spreading angle, which decreases at the same time, is able to reduce the lateral stability of the boom, but this is irrelevant anyway, particularly in its storage position.

With the help of the displacement and / or turning options, it is also possible to position the rocker cylinder relative to the boom

Modify base frame supporting swivel joint. As a result, the respective triangle, which includes the ends of the luffing cylinders on the base frame and on the boom and the swivel joint of the boom on the base frame, can be varied. The possible displacements allow for an improved flow of force, so that the components on the Wpp cylinder, base frame and boom can be optimized.

In a further development of the relocability shown above, it is considered particularly advantageous if the lower and / or upper ones

Bearing arrangements of the luffing cylinders simultaneously in opposite directions

Directions can be shifted towards or away from each other along the associated path. As a result, the inclination of the two luffing cylinders can be changed to the same extent, so that their connection to the boom always remains within the luffing plane, while the spreading angle between the longitudinal axes of the luffing cylinders is changed. This effectively prevents an undesired transverse displacement of the boom when the bearing arrangement (s) are moved.

The arrangement according to the invention can preferably be designed such that not only in the storage position but also in an assumed working position of the

Cantilever whose lateral stabilization can be increased if necessary by at least one of the two lower and / or upper bearing arrangements of the luffing cylinders being correspondingly displaceable in opposite directions. Overall, it is considered advantageous if the spread angle between the longitudinal axes of the two Luffing cylinder in the storage position and / or in the working position of the boom is changeable.

In this context, the spreading angle opened downwards or upwards in the working position of the boom can be greater than 0 ° to 45 °. In particular, the spreading angle opened downwards or upwards in the working position of the boom can be from 2 ° to 30 °. In contrast, the value of the spreading angle opened downwards or upwards in the storage position of the boom can be particularly preferably from 0 ° to 45 ° or from 0 ° to 6 °, so that an at least approximately parallel alignment of the luffing cylinders, for example during the process, is one with the one according to the invention Arrangement equipped crane vehicle is enabled.

Even if the base frame can be a component that can be connected, for example, to a region of a mobile crane, it is considered to be advantageous if the base frame itself is part of one versus one

Undercarriage is a rotating superstructure of a mobile crane. Of course, the base frame itself can be an uppercarriage or can be designed as an uppercarriage. Alternatively, the base frame itself can be part of the

Be under a truck crane. It goes without saying that the base frame itself can be such an undercarriage, or as

Undercarriage can be formed.

With the arrangement according to the invention that is now presented, an extremely compact design can be achieved, particularly in the storage position of its boom.

This is made possible by the tilted alignment of the luffing cylinders in the delivery position of the boom. In combination with the displaceable bearing arrangements, the lateral stability of the cantilever given to one another due to the A-shaped alignment of the luffing cylinders can be increased again, which sometimes has a significant influence on the design of the pivotable mounting of the

Can have outrigger. Usually, this is to be designed in combination with luffing cylinders, which are generally aligned parallel to one another, in such a way that they absorb the lateral forces acting on the cantilever, which is in particular in the working position, and, for example, into one equipped with them

Mobile crane can forward. Because of the at least in the working position of the boom A-shaped or V-shaped alignment of the two luffing cylinders to one statically advantageous and extremely stable triangle, in particular in the A-shape, the forces acting laterally on the boom can now at least partially be absorbed and transmitted, which means that the pivoting mounting of the boom and the base frame itself with regard to the capacity of such forces can be absorbed much simplified. As a result, said pivotable structural mounting of the boom and the base frame can, for example, be made correspondingly cheaper and slimmer.

In a preferred embodiment it is provided that the boom is a

Telescopic boom with a basic box and telescopic in and out

Inner boxes is. Then the Wpp cylinders attack the basic box of the boom.

Exactly two Wpp cylinders are particularly advantageously provided.

Furthermore, the invention is directed to a mobile crane, which one

Undercarriage and an arrangement according to the invention as described above comprises.

The advantages resulting from the mobile crane according to the invention have already been explained in more detail in connection with the arrangement according to the invention, so that in order to avoid repetitions at this point refer to the previous ones

Reference is made to this.

It is particularly advantageous, in particular in an embodiment of the mobile crane with a rubber-tired and road-mobile undercarriage, that the boom is supported on the undercarriage in the storage position of the jib.

An embodiment of the invention will be explained in more detail with reference to the following description. Show it:

FIG. 1 shows the schematic representation of a mobile crane according to the invention in a perspective representation,

FIG. 2 shows a schematic representation of an arrangement according to the invention of the mobile crane from FIG. 1 in a perspective representation,

Figure 3 shows the arrangement of Figure 2 in an alternative embodiment in a schematic representation of his view,

FIG. 4 shows the schematic illustration of a mobile crane according to the invention in a front view in a first embodiment,

FIG. 5 shows the schematic illustration of a mobile crane according to the invention in a front view in a further embodiment,

Figure 6 is a schematic representation of a mobile crane according to the invention in an embodiment as a mobile crane.

FIG. 1 shows a mobile crane 1 according to the invention. By way of example, this is a mobile crane 1 with a chain drive, which is equipped with one with two caterpillar tracks 2a, 2b spaced parallel to one another

Has undercarriage 2. Of course, a tire undercarriage not shown here could also be used, for example. On the undercarriage 2, an upper carriage 3 with a driving cabin 3a and a boom 4 is rotatably arranged. In the usual way, the boom 4 is designed as a telescopic boom that hydraulically moves out of and in from an outer basic box 4a

there is a telescopic inner box 4b. The boom 4 is pivotally supported on its upper end on the superstructure 3, so that it can be rocked between a horizontal storage position P1, which is only indicated here, into the working position P2 shown here, which is erected in relation thereto. The inclination of the

Boom 4 relative to the horizontal in the working position P2 shown here is to be regarded as an example, since this can of course also assume all other values deviating from the orientation of the boom 4 in its storage position P1.

The boom 4 can only be luffed within a vertical luffing plane WE, the orientation of which can be changed in a manner not shown by the possibility of a rotation of the uppercarriage 3 relative to the undercarriage 2 if required. The drive required for luffing and supporting the boom 4 takes place via two, preferably exactly two, opposite one another on the luffing plane WE

Rocker cylinder 5a, 5b. It can be seen that the two luffing cylinders 5a, 5b are arranged with respect to one another in such a way that their longitudinal axes x1, x2 in the working position P2 of the boom 4 shown here enclose a spreading angle a which is open at the bottom. In addition, the luffing cylinders 5a, 5b engage the boom 4 outside of its ends. Figure 2 shows an arrangement 10 according to the invention, which some of the already in Figure

I includes parts of the mobile crane 1 shown. Specifically, the arrangement 10 has the boom 4, which is reduced here to its basic box only for reasons of clarity, and the two luffing cylinders 5a, 5b, all of which are supported on a base frame 11 of the arrangement 10 via their lower ends. The boom 4 can be rocked about a horizontal pivot axis S on the base frame

I I mounted, wherein the two Wpp cylinders 5a, 5b are articulated on the base frame 11. For this purpose, two indicated lower bearing arrangements 12a, 12b are provided on the base frame 11 and two indicated upper bearing arrangements 13a and 13b on the boom 4, which are each arranged on the two wrap cylinders 5a, 5b. Each of these bearing arrangements 12a, 12b; 13a, 13b is designed in a manner that cannot be seen in more detail as a universal joint or ball joint, around the two Wpp cylinders 5a, 5b, which is necessary when the boom 4 is wobbled

To allow freedom of movement.

In addition, with reference to the rocker cylinders 5a, 5b from FIG. 1, it can be seen that the rocker cylinders 5a, 5b, which are designed as hydraulic cylinders, are preferably articulated with the upper ends of their piston rods on the basic box 4a outside of its upper and lower ends. The two rocker cylinders 5a, 5b engage approximately in the middle of an upper half of the basic box 4a on the basic box 4a. It is preferably provided that the two Wpp cylinders 5a, 5b engage in an area on the basic box 4a of the boom 4 which extends in the longitudinal direction of the

Basic box 4a seen at least 10%, preferably at least 20%, particularly preferably at least 30%, of the total length of the basic box 4a is in each case spaced from the upper and also the lower end of the basic box 4a.

In principle, it is possible for the base frame 11 shown here to be part of the superstructure 3 of the mobile crane 1 from FIG. 1 which is rotatable relative to the undercarriage 2, or else the superstructure 3 itself. As an alternative to this, it is conceivable that said base frame 11 is part of the undercarriage 2 of the mobile crane 1 from FIG. 1 or else the undercarriage 2 itself. FIG. 3 shows the arrangement 10 from FIG. 2 in a side view remove. In the present case, the horizontal storage position P1 of the boom 4, which is also reduced to its basic box only for reasons of clarity, is shown, while its working position P2 is indicated by broken lines. The boom 4 extends in its storage position P1, for example, parallel to a horizontal direction X, while the two are on the luffing plane WE

opposite rocker cylinders 5a, 5b, which are spaced apart in a transverse direction Y, lie one on top of the other in this illustration. Consequently, only the rocking cylinder 5b lying in the foreground can be seen, while the rocking cylinder 5a behind it is covered by it. The change in the inclination of the wpp cylinders 5a, 5b in the working position P2 of the boom 4 is also indicated accordingly by the use of broken lines.

As can be seen, the longitudinal axis x1, x2 of the luffing cylinders 5a, 5b projected onto the luffing plane WE and a vertical direction Z which extends orthogonally to the horizontal direction X within the luffing plane WE form an inclination angle b between them as soon as the boom 4 is in its storage positions P1 . In other words, the two Wpp cylinders 5a, 5b are inclined in the storage position P1 of the boom 4 with respect to the vertical direction Z. In the present case, said angle of inclination b in the storage position P1 of the boom 4 is approximately 75 °. Depending on

Embodiment of the arrangement 10, the angle of inclination b in the storage position P1 of the boom 4 can also be so large that the wupping cylinders 5a, 5b can preferably also extend parallel to below the horizontal direction X in a manner not shown here.

FIG. 4 illustrates the structure of the arrangement 10 from FIGS. 2 and 3 using an alternative embodiment. As can be seen in the view of the arrangement 10 shown here, the upper bearing arrangements 13a, 13b of the two

Luffing cylinders 5a, 5b can of course also be arranged laterally on the basic box of the boom 4. In the present case, the two lower bearing arrangements 12a, 12b can be displaced in a manner not shown along a path P running perpendicular to the Wpp plane WE. Said path can have a straight and / or curved course, at least in sections, which is indicated here by way of example as curved. It is provided that the two bearing arrangements 12a, 12b simultaneously along path P in opposite directions R1, R2 towards or away from each other are relocatable. Due to the displaceable structure of the bearing arrangements 12a, 12b, it is possible to move the between the longitudinal axes x1, x2 of the two

Rocker cylinders 5a, 5b to change the included spreading angle a. The change of the spreading angle a which is open downwards or towards the base frame 11 can take place in the storage position P1 and / or in the working position P2 of the boom 4. The spread angle a can assume values of greater than 0 ° to 45 °, which can preferably be greater in the working position P2 than in the storage position P1 of the boom 4. Thus, the spreading angle a in the storage position P1 of the boom 4 can be, for example, from 0 ° to 6 °, so that the two luffing cylinders 5a, 5b run almost parallel to one another in order, for example, to obtain dimensions that are as compact as possible during the movement of the vehicle 1 equipped in this way.

FIG. 5 illustrates a further alternative embodiment of the arrangement 10 according to the invention. The lower bearing arrangements 12a, 12b can be seen here relative to the upper bearing arrangements 13a, 13b in such a way that the spreading angle a enclosed between the two rocking cylinders 5a, 5b is now open upwards. In other words, the arrangement of the two rocking cylinders 5a, 5b tapered towards the base frame 11. In the present case, the upper bearing arrangements 13a, 13b can also be changed in their respective positions along a path P, which results in a corresponding variability in the spreading angle a open at the top.

Of course, it is conceivable that the upper and lower bearing arrangements 12a, 12b; 13a, 13b are displaceable such that the spread angle a can be opened upwards or downwards if necessary.

FIG. 6 is a schematic representation of an inventive one

Mobile crane 1 is shown in training as a mobile crane which can be moved on public roads and which accordingly has an undercarriage 2 with rubber tires

Wheel tire 2c issued on four axes, for example. On the undercarriage 2, a superstructure 3, which can be pivoted about a vertical axis of rotation, is mounted with the luffing jib 4 in the usual manner. It can be seen that in the substantially horizontal storage position P1 of the boom 4 already described for FIG. 3, the boom 4 is supported on the undercarriage 2 via a support 14. For this purpose, the support 14 extends from an upper side of the undercarriage 2 to the lower side of a basic box 4a of the boom 4 vertically and comes to rest there.

Reference list

1 mobile crane

2 undercarriages

2a caterpillar drive

2b caterpillar drive

2c wheel tires

3 superstructures

3a driving cabin

4 outriggers

4a basic set

4b inner box

5a rocker cylinder

5b rocker cylinder

10 arrangement

11 base frame

12a bearing arrangement, below

12b bearing arrangement, below

13a bearing arrangement, top

13b bearing arrangement, top

14 Support a Spread angle b Tilt angle P Path

P1 storage position P2 working position R1 direction

R2 direction

S Swivel axis WE rocker level

x1 longitudinal axis x2 longitudinal axis

X horizontal direction Y transverse direction Z vertical direction

Claims

1. Arrangement (10) with a boom (4) which can be rocked over at least two luffing cylinders (5a, 5b) within a vertical wupping plane (WE) between a storage position (P1) and a working position (P2), the boom (4 ) opposite wpp cylinders (5a, 5b) in the working position (P2) enclose a spreading angle (a) between their longitudinal axes (x1, x2) and engage the wpp cylinders (5a, 5b) on the boom (4) outside its ends, characterized in that in the storage position (P1) of the boom (4), the longitudinal axis (x1, x2) of a rocking cylinder (5a, 5b) projected onto the luffing plane (WE) and a vertical direction (Z) extending within the luffing plane (WE) an inclination angle (b ) shoot between them.

2. Arrangement (10) according to claim 1, characterized in that in the

Storage position (P1) of the boom (4) the angle of inclination (b) is from 60 ° to 120 °, preferably from 80 ° to 100 °, particularly preferably from 90 ° to 97 °.

3. Arrangement (10) according to any one of the preceding claims, characterized

characterized in that the boom (4) is mounted on a base frame (11) so that it can be rocked, the base frame (11) each having lower bearing arrangements (12a, 12b) in the form of a universal or ball joint, via which the rocking cylinders (5a, 5b) the base frame (11) are articulated.

4. Arrangement (10) according to any one of the preceding claims, characterized

characterized in that the boom (4) is mounted on a base frame (11) so that it can be rocked, the boom (4) each having upper bearing arrangements (13a, 13b) in the form of a universal or ball joint, via which the rocking cylinders (5a, 5b) the boom (11) are articulated.

5. Arrangement (10) according to claim 3 and 4, characterized in that at least one of the bearing arrangements (12a, 12b; 13a, 13b) can be variably positioned along a path (P) running perpendicular to the seesaw plane (WE), the path ( P) has a straight or curved course, at least in sections.

6. Arrangement (10) according to claim 5, characterized in that the

Bearing arrangements (12a, 12b; 13a, 13b) can simultaneously be displaced in opposite directions (R1, R2) towards or away from each other along the path (P).

7. Arrangement (10) according to any one of the preceding claims, characterized

characterized in that the spreading angle (a) between the longitudinal axes (x1, x2) of the two luffing cylinders (5a, 5b) in the storage position (P1) and / or in the working position (P2) of the boom (4) can be changed.

8. Arrangement (10) according to claim 7, characterized in that the spread angle (a) in the working position (P2) of the boom (4) is greater than 0 ° to 45 °, preferably from 2 ° to 30 °.

9. Arrangement (10) according to claim 7 or 8, characterized in that the spread angle (a) in the storage position (P1) is from 0 ° to 45 ° or from 0 ° to 6 °.

10. Arrangement (10) according to any one of claims 3 to 9, characterized in that the base frame (11) is part of an upper carriage (3) which is rotatable relative to an undercarriage (2) of a mobile crane (1) or the upper carriage (3) itself.

11. The arrangement (10) according to any one of claims 3 to 8, characterized in that the base frame (11) is part of an undercarriage (2) of a mobile crane (1) or the undercarriage (2) itself.

12. Arrangement (10) according to any one of the preceding claims, characterized

characterized in that the boom (4) is a telescopic boom with a basic box (4a) and telescopic inner boxes (4b).

13. Arrangement (10) according to claim 12, characterized in that the

Grip the luffing cylinder (5a, 5b) on the basic box (4a) of the boom (4).

14. Arrangement (10) according to any one of the preceding claims, characterized

characterized in that exactly two rocker cylinders (5a, 5b) are provided.

15. Mobile crane comprising an undercarriage (2) and an arrangement (10) according to one of the preceding claims.

16. The arrangement (10) according to claim 1 or 2, characterized in that in the storage position (P1) of the boom (4) the boom (4) is supported on the undercarriage (2).