MOBILE CRANE WITH FOLDABLE AISLE

Description

[0001] The present invention relates to a mobile crane, in particular a crawler crane, according to the preamble of claim 1.

[0002] Mobile cranes are typically used when stationary cranes are unavailable at the work site or cannot be used for other reasons, or only with considerable effort. Mobile cranes can have a chassis with wheels or tracks and usually feature a rotating superstructure mounted on the chassis, to which a luffing main boom is attached. Typically, the superstructure also includes an operator's cab at the front for operating the crane and ballast at the rear.

[0003] Larger mobile cranes must be disassembled into smaller transport units for transport to the work site. To safely assemble such a mobile crane, especially a crawler crane, standard-compliant access to the operator's cab and the technical systems to be installed is essential. This often presents the operating personnel or assembly team with complex challenges regarding the installation and dismantling of access systems. These access systems, which may include access stairs, walkways, or platforms / platforms for lateral access, frequently require the use of auxiliary cranes and / or several people to attach them to the mobile crane. Sliding platforms underneath from the side is not possible due to the robust design of modern superstructures. Removing railings and platforms, on the other hand, is complex and typically requires several people and / or equipment.

[0004] A mobile crane with the features of the preamble of claim 1 is already described in CN 203 925 307 U. DD 130 365 A1 also shows a similar arrangement.

[0005] The object of the present invention is therefore to provide an easy-to-install access system for a mobile crane. The assembly and disassembly of the access system components should be quick and possible without external aids.

[0006] According to the invention, this problem is solved by a mobile crane with the features of claim 1. Accordingly, a mobile crane, in particular a crawler crane, is proposed, comprising an undercarriage with a chassis and a superstructure rotatably mounted on the undercarriage with a swiveling boom. At least two platforms are provided laterally on the superstructure, allowing access to the superstructure by operating personnel. The platforms are permanently attached to the superstructure, i.e., they always remain on the superstructure and are not removed for transport.

[0007] According to the invention, the at least two platforms each comprise a floor and a railing, which can be moved from a transport position to a working position and vice versa. In the transport position, the platforms, or rather the floor and railing of the platforms, rest against the superstructure and thus assume a space-saving position suitable for transport. In the working position, the platforms are accessible to operating personnel and secured by the railings. This means that in the working position, the floors are oriented so that they are accessible, and, moreover, the persons walking on the platforms are secured against falling by the railings.

[0008] Because the platforms and railings remain attached to the superstructure and can be moved from a folded or "folded" position for transport to a working position that allows access to the superstructure, a complex and time-consuming assembly and disassembly process is eliminated. The platforms are designed and positioned in such a way that they can be easily installed or moved into the working position from the ground by a single person without the need for an auxiliary crane or similar equipment. The railings do not need to be attached separately to the platforms. Ideally, installation and disassembly can be carried out without additional hand tools. Overall, this results in a more convenient, faster, and simpler assembly and disassembly process for the mobile crane.

[0009] According to the invention, the platforms can be pivoted into the working position about at least two pivot axes, preferably two of the at least two pivot axes not being parallel to each other. The platforms are therefore not moved into the working position by simply unfolding them about a single axis, for example a horizontal one, but rather an installation process consisting of several individual movements takes place. These individual movements can be performed simultaneously or sequentially.

[0010] According to the invention, the platforms are pivotable into the working position about two non-parallel, in particular two perpendicular, pivot axes, and the railings are pivotable, foldable, slidable and / or telescopically extendable into the working position. The movement sequence for the platform therefore differs from the movement sequence for the railing when moving the platform from the transport position to the working position and vice versa.

[0011] Advantageous embodiments of the invention will become apparent from the dependent claims and the following description.

[0012] In another possible embodiment, the platforms and railings are movable independently of each other. Preferably, the platforms and railings are also independently connectable to the platforms and railings of adjacent platforms.

[0013] In another possible embodiment, the platforms can be detachably connected to each other in their working positions. This results in a stable and continuous walkway for the upper carriage, which, compared to known walkways that, for example, comprise several spaced-apart platforms (i.e., separated from each other by gaps), ensures greater footing safety for the operating personnel.

[0014] Preferably, the platforms or parts thereof can be interlocked in their working positions and / or bolted and / or screwed together. Interlocking connections provide a particularly convenient way to connect the platforms without the need for additional tools.

[0015] The connections between the platforms can be designed to be reversibly locked, for example by means of a bolt or snap-fit ​​connection. This prevents the platforms from unintentionally coming loose.

[0016] In another possible embodiment, the shelves are provided with hook elements by which they can be suspended from the floor mounting elements of adjacent platforms in the working position. The shelves are pivotable about a horizontal axis, with the hook elements for the suspension connection being arranged on the side opposite the pivot axis. A particularly simple design results from the fact that the hook elements of one platform are placed or suspended on the pivot axis of the adjacent platform, with the openings of the hook elements facing downwards in the working position and resting on the pivot axis.

[0017] The horizontal pivot axes of the platforms are thus represented by the aforementioned floor mounting elements. They are preferably pivoted about a pivot axis, particularly a vertical one, when the platforms are moved from the transport position to the working position.

[0018] Alternatively or additionally, one or more platforms can be attached to floor mounting elements located on the superstructure. These could be platforms positioned, for example, at the ends or in bends or curves of the walkway. These platforms are attached directly to the superstructure.

[0019] The suspension connections can be reversibly locked via locking elements to prevent unintentional loosening of the suspension connections.

[0020] In another possible embodiment, the railings are designed to be pivotable, foldable, sliding, and / or telescopic, and connectable to adjacent railings and / or directly to the superstructure via railing fastening elements. This connection can be a hook-in type, which is preferably reversibly lockable.

[0021] The railing of each platform can comprise several articulated struts. By sliding, pivoting, unfolding, and / or telescoping one or more sections, the railings can be brought into the working position and connected to each other. The railing of one or more platforms can alternatively or additionally be connected directly to the superstructure or to railing mounting elements attached to it. These could be, for example, platforms located at the ends or in bends or curves of the walkway.

[0022] The railings can include foldable parts, which can be designed, for example, as individual pivoting struts or as parallelogram guides. In another possible embodiment, the superstructure includes a driver's cab in the area of ​​which at least one further platform is arranged, wherein preferably the at least three platforms, in the working position, form a continuous walkway along one side of the superstructure. This allows the driver's cab to be conveniently accessed via the walkway connection formed by the platforms according to the invention. The walkway can extend from the rear of the superstructure to the driver's cab.

[0023] In another possible embodiment, access to the superstructure walkway is provided at the rear of the superstructure opposite the driver's cab. Thus, unlike many conventional access systems, access is not at the front in the area of ​​the driver's cab.

[0024] In another possible embodiment, an access element with a floor and at least one railing can be attached to the superstructure in such a way that access to the superstructure, formed by the platforms in their working position, is possible via the access element. The access element can be attached to one of the folding platforms, directly to the superstructure, or to both. The railing of the access element can be connected to a railing of one of the platforms and / or directly to the superstructure. This preferably also applies to the floor of the access element.

[0025] In another possible embodiment, the access element comprises, in particular, a pivotable access staircase or fastening elements for attaching an access staircase. This allows access to the walkway formed by the platforms at a certain height on the superstructure. The access staircase can also be a ladder.

[0026] In another possible embodiment, the superstructure is provided with a superstructure ballast which can be lifted from the ground and placed on the ground by a lifting mechanism of the mobile crane. The lifting mechanism can be a self-loading system of the mobile crane. The access element is attached to, or can be attached to, the superstructure ballast, in particular to a ballast mounting plate of the superstructure ballast.

[0027] By raising the superstructure ballast using the lifting mechanism, the access element can be brought to the height of the superstructure walkway. This allows the access element to be conveniently attached to the superstructure ballast from the ground, for example, by hooking it onto the ballast, and then lifted to the appropriate height so that it can be connected to the walkway. This eliminates the need for an external lifting device. The self-loading system of the superstructure ballast automatically positions the access element at the correct walkway level.

[0028] It may be provided that the access element can be hooked into / onto corresponding fastening elements, which are arranged, for example, on the ballast mounting plate or a ballast element of the upper carriage ballast.

[0029] In another possible embodiment, the access element is pivotably mounted or can be mounted on the superstructure ballast. After being raised via the superstructure ballast or by means of the lifting mechanism, the access element can be connected to the superstructure walkway, in particular to a platform of the walkway, by pivoting it. Alternatively or additionally, the access element can be connected directly to a fastening element arranged on the superstructure by pivoting it. The rotation of the access element can be easily carried out by an operator from the ground. Here, too, a reversible locking mechanism for the access element on the walkway or on the superstructure can be provided.

[0030] In another possible embodiment, the upper surface of the superstructure is accessible and a railing is provided on the upper surface, particularly at the edge. Access to the upper surface of the superstructure is preferably via the platform formed by the platforms according to the invention, for example, via an access ladder or stairs. This allows the operating personnel to climb onto the upper surface of the superstructure and reach the technical systems or other crane components.

[0031] In another possible embodiment, at least one floor element is mounted on the upper side of the superstructure in a slidable and / or foldable or pivotable manner, preferably forming a walkable area on the upper side of the superstructure by a plurality of such floor elements. The slidability or pivotability of the floor elements allows the walkable area to be flexibly adjusted.

[0032] The floor elements are particularly self-supporting and of lightweight construction, for example as a grid. They are preferably attached to, or can be attached to, a base frame of the superstructure and / or to fastening elements arranged on it. Floor elements with different shapes, for example with different widths and / or lengths, can be provided. The floor elements, like the platforms, can also have hook elements by which they can be attached to or placed on corresponding fastening elements of the superstructure.

[0033] It is further conceivable that the superstructure comprises at least two platforms according to the invention on each side, i.e., has a superstructure walkway on each side. One of the two superstructure walkways or walkway connections can be longer and extend to the driver's cab.

[0034] The platforms and / or the access module floor are constructed using lightweight materials. This makes handling and installation of the platforms easier for the operator. The floors may be designed as grids.

[0035] Furthermore, the platforms can be modular in design or part of a modular access system. This allows the geometry of the upper carriage access to be adapted to the specific machine and, for example, expanded as needed.

[0036] Further features, details and advantages of the invention will become apparent from the exemplary embodiments explained below with reference to the figures. The figures show: Figure 1: the mobile crane according to an embodiment in a perspective overall view; Figure 2: a perspective view of three platforms according to an embodiment in the transport position; Figure 3: the platforms according to Figure 2, wherein a platform is pivoted about a first axis; Figure 4: the platforms according to Figure 3 , wherein the pivoted platform is pivoted about another axis; Figure 5: the platforms according to Figure 4 , with the railing of the pivoted platform unfolded; Figure 6: the platforms according to Figure 2 , with all platforms in the working position; Figure 7: an enlarged view of the upper structure of the mobile crane according to Figure 1 with lowered superstructure ballast; Figure 8: the mobile crane according to Figure 7 with raised superstructure ballast and attached access module; and Figure 9: a perspective view of several floor plates on the top of the superstructure according to an exemplary embodiment.

[0037] The Figure 1Figure 1 shows a perspective overall view of an embodiment of the mobile crane 10 according to the invention, which in this case is a crawler crane. The crawler crane 10 comprises an undercarriage 12 with two crawler tracks 13 and a superstructure 14 rotatably mounted on the undercarriage 12 about a vertical axis.

[0038] A main boom 16, pivotable about a horizontal axis, is attached to the front of the superstructure 14 (left in the image). The main boom 16 is braced via an A-frame 17, which is pivotably mounted on the superstructure 14. Also located in the front of the superstructure 14 is a driver's cab 18 for controlling the mobile crane 10. At the rear (right in the image) is a superstructure ballast 20, which comprises a ballast mounting plate 22 and a number of ballast elements 24 or ballast plates stacked on it.

[0039] On the side of the superstructure 14 where the driver's cab 18 is located, a superstructure access platform 31 in the form of a continuous walkway is arranged, which can be accessed via an access staircase in the area of ​​the superstructure ballast 20. The superstructure access platform 31 provides safe access for the operating personnel to the elevated driver's cab 18 and, via a ladder attached to the side of the superstructure 14, access to the top of the superstructure 14.

[0040] The upper carriage access 31 is formed by a multitude of modularly constructed and lightweight platforms 30, which, according to an exemplary embodiment, are arranged in the Figures 2-6The platform modules or platforms 30 according to the invention are shown in perspective in various positions. They are fixed, i.e., permanently attached to the superstructure 14 and are not removed or disassembled for transport. Instead, the platforms 30 can be moved into a space-saving transport position in which they lie flat against the side of the superstructure 14. This transport position is shown in the Figure 2 shown.

[0041] The platforms 30 according to the invention each comprise a pivotable base 32, which in this embodiment is designed as a substantially square grid, and a fold-out railing 34. The platforms 30 are firmly connected to the superstructure 14 or to a base frame of the superstructure 14 via brackets 37. A locking device (not shown) can be provided for each platform 30, which fixes the platforms 30 or bases 32 in the transport position so that they do not unfold unintentionally.

[0042] In each bracket 37, a floor mounting element 38, designed as a swivel bracket, is pivotably mounted about a vertical axis. This vertical axis forms a first pivot axis A1, as shown in the Figure 4 as indicated. The floor 32 and the railing 34 of the platform 30 are attached or supported on the swivel bracket 38.

[0043] As in the Figure 3As can be seen, the platforms 30 can be rotated from their transport position about the first pivot axis A1 by (at least) 90°. An optional stop can be provided here to block rotation beyond 90°. The individual platforms 30 can be moved or pivoted independently of one another. The floor 32 and the railing 34 are pivoted together about the first pivot axis A1.

[0044] The swivel bracket 38 comprises an elongated arm that is arranged perpendicular to the swivel axis A1 and forms a second swivel axis A2, since the base 32 is pivotably mounted on the elongated arm of the swivel bracket 38. As shown in the Figure 4As can be seen, the base 32 can be pivoted around the elongated arm of the swivel bracket 38 or around the second pivot axis A2 (but not the railing 34) and folded down so that it is horizontally aligned. The base 32 can therefore also be pivoted by (at least) 90° around the second pivot axis A2. The pivot axes A1 and A2 are perpendicular to each other. The second pivot axis A2 lies in a horizontal plane.

[0045] The short arm of the swivel bracket 38, forming the first pivot axis A1, and its long arm are connected by a stiffening angle element or angle plate. The swivel bracket 38 is rotatably mounted in the support 37 via two bearing points over the short arm. Of course, other arrangements or shapes of the bearings or supports 37 are also conceivable.

[0046] As in the Figure 5As shown, the railing 34 of the platform 30 can be unfolded. For this purpose, the railing 34 has a vertical section fixedly connected to the pivot bracket 38, on which a folding section 35 is pivotally mounted. The folding section 35 comprises two crossbars pivotally mounted on the vertical railing section, which are articulated at their ends spaced from the vertical railing section by a longitudinal strut. Thus, the folding section 35 forms a parallelogram linkage, which, in the fully unfolded state, forms a rectangle (i.e., the crossbars are perpendicular to the vertical railing section).

[0047] The right one in the Figure 5The platform 30 shown is fully extended and in the working position, in which it can be accessed by an operator, who is secured against falls by the extended railing 34. A lever 42 is provided to facilitate the unfolding of the folding section 35. In this embodiment, it is located in the area of ​​the articulated connection between the lower cross member and the longitudinal member of the folding section 35. Of course, other positions and / or shapes of such an actuating element are conceivable to facilitate the unfolding of the folding section 35.

[0048] The Figure 6Figure 1 shows three platforms 30 in the working position, which form a continuous walkway. The superstructure access 31 is constructed from a multitude of such platforms 30, which can differ in their dimensions. For example, some platforms 30 may have longer and / or angled floors 32. This allows the superstructure access 31 formed by the platforms 30 to be adapted to the geometry of the superstructure 14 and, for example, routed around one or more corners, so that a continuous connection or walkway exists from the rear to the driver's cab 18 (see Figure 1). Figure 1 ).

[0049] In contrast to many known superstructure access systems, the platforms 30 according to the invention connect directly to one another in the working position, creating a seamless, continuous superstructure access system 31. This minimizes the risk of falls and injuries. In addition to the foldable platforms 30 according to the invention, the superstructure access system 31 can also include permanently installed, i.e., immovable, parts, such as plates / floors rigidly attached to the superstructure 14, railing sections, or the like. Alternatively or additionally, it is conceivable that the superstructure access system 31 includes one or more foldable, telescopic, sliding, or otherwise movable parts. Such parts can be provided, in particular, in corner or curve areas or at the ends of the superstructure access system 31.

[0050] The platforms 30 are therefore connected to adjacent platforms 30 in the working position (cf. Figure 6For this purpose, the shelves 32 have two hook elements 36 on the sides opposite the swivel brackets 38. These hook elements can be placed or hooked onto the long arms of the swivel brackets 38 of the adjacent platforms 30 when the shelves are folded around the second swivel axes A2. The shelves 32 of the adjacent platforms 30 are thus detachably connected to one another by means of hook connections. Optionally, a locking mechanism can be provided here to lock the shelves 32 to the adjacent platforms 30. A snap-fit ​​or bolt connection would be conceivable, for example.

[0051] The railings 34 of the adjacent platforms 30 can also be connected to each other in the working positions. For this purpose, the upper crossbars of the folding sections 35 each have a railing fastening element 40 at the end opposite the vertical railing section, which can be reversibly connected to a corresponding fastening element at the top of the vertical section of the railing 34 of the adjacent platform 30, in particular by means of a hook-in connection. A reversible locking mechanism, for example by means of a snap-fit ​​or bolt connection, can also be provided here.

[0052] Since the platform modules 30 are of lightweight construction and can be moved directly between their transport and working positions without the need for additional parts such as railings, the installation of the superstructure access platform 31 can be carried out quickly and conveniently by a single operator from the ground. Due to its modular design, the superstructure access platform 31 can be adapted or extended as needed. This allows the platforms 30 according to the invention to be used on any superstructure geometry.

[0053] The Figure 7Figure 1 shows an enlarged section of the superstructure 14 of the mobile crane 10 according to the invention. The superstructure ballast 20 can be lifted from the ground or lowered from the superstructure 14 onto the ground by means of a lifting mechanism of the mobile crane 10, which can also be referred to as a self-loading system. This allows the ballast receiving plate 22 on the ground to be loaded with ballast elements 24, and the fully assembled or stacked superstructure ballast 20 to then be lifted onto the superstructure 14 by means of the lifting mechanism.

[0054] The lifting mechanism is also used here to set up access to the superstructure walkway 31. Access is provided at the rear via an access element 50 or access module, also constructed of lightweight materials, which has a floor 52 (in particular a grid floor) and two railings 54 on both sides. The access element 50 is pivotally attached to the ballast mounting plate 22, in particular via a hook connection. Assembly takes place with the superstructure ballast 20 detached, as shown in the Figure 7 to see.

[0055] By raising the superstructure ballast 20 using the lifting mechanism, the access module 50 is automatically positioned at the correct height – namely, at the level of the superstructure walkway 31. At the rear, the superstructure walkway 31 has a gap in the railing to which the access element 50 is attached. This gap can be provided, for example, by a special platform 30 (such as a simple folding floor) or by a platform permanently connected to the superstructure 14. As shown in the Figure 8 As shown, the access element 50 is rotated by an operator from the ground to the upper carriage access point 31 (see arrows 70, which indicate the lifting and rotation directions) and connected to the upper carriage access point 31. A locking mechanism may be provided here.

[0056] An access staircase 56 can now be attached to special fastening elements of the access element 50, in particular hooked onto it, so that the elevated upper carriage access 31 can be climbed by an operator.

[0057] In the area of ​​the (attached) access element 50 there is a ladder 28, which is particularly extendable (see Figure 7 ), via which the upper surface of the superstructure 14 can be accessed. For safety, superstructure railings 26 are attached to the edges of the upper surface of the superstructure 14.

[0058] The superstructure 14 is accessed via self-supporting, lightweight profiled floors or floor elements 60. An embodiment of a walkable area of ​​the superstructure 14 formed by such floor elements 60 is shown in the Figure 9The floor elements 60 are easily movable on the existing base frame of the superstructure 14 and are also foldable. For this purpose, they have hook elements 62 on their sides, which allow them to rest on corresponding fastening elements on the base frame. The floor elements 60 are shaped differently, i.e., they vary in length and width, and can therefore be flexibly adapted to the geometry of the superstructure and to objects or obstacles installed on its upper surface. Such a walkable area made of profiled floors or floor elements 60 can be used not only on the superstructure but also in other areas, for example, instead of the grid floors in the folding platforms.

[0059] The platforms 30 according to the invention enable quick and easy installation of the upper carriage access 31 from the ground and by a single operator, without external aids such as an auxiliary crane or hand tools. Although they are primarily made of metal, they are of a lightweight construction and therefore easy to handle. Reference symbol list:

[0060] 10 Mobile crane 12 Undercarriage 13 Crawler undercarriage 14 Superstructure 16 Main boom 17 A-frame 18 Operator's cab 20 Superstructure ballast 22 Ballast mounting plate 24 Ballast element 26 Superstructure railing 28 Access ladder 30 Platform 31 Superstructure access 32 Floor 34 Railing 35 Folding section 36 Hook element 37 Bracket 38 Floor mounting element (swivel bracket) 40 Railing mounting element 42 Handle 50 Access element 52 Floor 54 Railing 56 Access stairs 60 Floor plate 62 Hook element 70 Direction of movement A1 First slewing axis A2 Second slewing axis

Claims

1. A mobile crane (10), in particular a crawler crane, comprising an undercarriage (12) having a chassis (13) and a superstructure (14) rotatably supported on the undercarriage (12) and having a pivotable boom (16), wherein at least two platforms (30) are permanently arranged laterally at the superstructure (14) via which the superstructure (14) is walkable, wherein the platforms (30) each comprise a base (32) movable from a transport position in which they contact the superstructure (14) into a work position in which the bases (32) are walkable, movable, and vice versa, characterized in that the platforms each also comprise a railing (34) in which the bases (32) are secured in a working position by the railings (34) so that the platforms (30) are pivotable about at least two pivot axes (A1, A2) into the work position, with two of the at least two pivot axes (A1, A2) preferably not being in parallel with one another and so that the bases (32) are pivotable into the work position about two non-parallel pivot axes (A1, A2), in a particular two pivot axes (A1, A2) perpendicular to one another and the railings (34) are pivotable, foldable, displaceable, and / or telescopable into the work position.

2. A mobile crane (10) in accordance with one of the preceding claims, characterized in that the bases (32) and the railings (34) of the platforms (30) are movable independently of one another and are preferably connectable independently of one another to bases (32) / railings (34) of adjacent platforms (30).

3. A mobile crane (10) in accordance with one of the preceding claims, characterized in that the platforms (30) are releasably connectable to one another in their work positions, in particular hookable into one another and / or pinnable and / or screwable to one another4. A mobile crane (10) in accordance with one of the preceding claims, characterized in that the bases (32) have hook elements (36) via which they can be hooked to base fastening elements (38) of adjacent platforms and / or to base fastening elements at the superstructure (14) in the work position.

5. A mobile crane (10) in accordance with one of the preceding claims, characterized in that the railings (34) are pivotable, foldable, displaceable, and / or telescopable and are connectable to adjacent railings (34) and / or to the superstructure (14) via railing fastening elements (40).

6. A mobile crane (10) in accordance with one of the preceding claims, characterized in that the superstructure (14) comprises an operator's cabin (18) in whose area at least one further platform (30) is arranged, with the at least three platforms (30) preferably forming a continuous superstructure walking platform (31) along one side of the superstructure (14) in the work position.

7. A mobile crane (10) in accordance with claim 6, characterized in that access to the superstructure walking platform (31) takes place in the region of the rear of the superstructure (14) disposed opposite the operator's cabin (18).

8. A mobile crane (10) in accordance with one of the preceding claims, characterized in that an access element (50) having a base (52) and a railing (54) is attachable to the superstructure (14) such that a superstructure walking platform (31) formed by the platforms (30) located in the work position is accessible via the access element (50).

9. A mobile crane (10) in accordance with claim 8, characterized in that the access element (50) comprises access steps (56) that are in particular pivotable or fastening elements for fastening access steps (56).

10. A mobile crane (10) in accordance with claim 8 or claim 9, characterized in that the superstructure (14) has superstructure ballast (20) that can be raised from the ground and placed on the ground via a lifting mechanism of the mobile crane (10), with the access element (50) being fastened or fastenable to the superstructure ballast (20), in particular to a ballast receiving plate (22) of the superstructure ballast (20) and can be moved to the height of the superstructure walking platform (31) by raising the superstructure ballast (20).

11. A mobile crane (10) in accordance with claim 10, characterized in that the access element (50) is pivotably supported or supportable at the superstructure ballast (20), with the access element (50) raised via the superstructure ballast (20) being connectable to the superstructure walking platform (31), in particular to a platform (30), by pivoting.

12. A mobile crane (10) in accordance with one of the preceding claims, characterized in that the upper side of the superstructure (14) is walkable; and in that a superstructure railing (26) is provided at the upper side of the superstructure (14), with access to the upper side of the superstructure (14) preferably taking place starting from a superstructure walking platform (31) formed by the platforms (30) located in the work position via an access ladder (28) or access steps.

13. A mobile crane (10) in accordance with claim 12, characterized in that at least one base element (60) is displaceably and / or foldably supported at the upper side of the superstructure (14), with a walkable region preferably being formed by a plurality of such base elements (60) at the upper side of the superstructure (14).