MOBILE CRANE WITH A COUNTERWEIGHT DEVICE, COUNTERWEIGHT DEVICE AND METHOD FOR ASSEMBLING SUCH

Abstract

The disclosure relates to a mobile crane comprising a mobile undercarriage, an upper carriage mounted rotatably on the undercarriage and a counterweight device that can be coupled to the upper carriage and has a counterweight base plate, a carrier plate and at least two suspension weights that can be releasably connected to the carrier plate, wherein the carrier plate can be placed on the counterweight base plate and comprises first connecting elements for producing a first suspension connection with first connecting elements of the suspension weights. According to the disclosure, the carrier plate and the suspension weights are designed as a jointly liftable assembly unit, wherein the suspension weights have slinging means for lifting the entire assembly unit. The carrier plate comprises second connecting elements for establishing a second connection with second connecting elements of the suspension weights.

Claims

1. Mobile crane comprising a mobile undercarriage, an upper carriage mounted rotatably on the undercarriage and a counterweight device that can be coupled to the upper carriage and has a counterweight base plate, a carrier plate and at least two suspension weights that can be releasably connected to the carrier plate, wherein the carrier plate can be placed on the counterweight base plate and comprises first connecting elements for producing a first suspension connection with first connecting elements of the suspension weights, wherein the carrier plate and the suspension weights are designed as a jointly liftable assembly unit and the suspension weights have slinging means for lifting the entire assembly unit, wherein the carrier plate comprises second connecting elements for establishing a second connection with second connecting elements of the suspension weights, which carrier plate is designed to block a release of the first suspension connection when the assembly unit is lifted over the suspension weights.

2. Mobile crane according to claim 1, wherein the upper carriage comprises a ballasting device, which is designed to lift the counterweight device from a storage area of the undercarriage and deposit it thereon.

3. Mobile crane according to claim 2, wherein the counterweight device comprises at least one coupling element extending substantially perpendicular to the counterweight base plate and connected thereto for lifting and coupling the counterweight device to the upper carriage.

4. Mobile crane according to claim 3, wherein the at least one coupling element has a coupling portion at an end opposite the counterweight base plate, via which a coupling to the ballasting device, to a ballasting cylinder of the ballasting device, can be established.

5. Mobile crane according to claim 4, wherein the coupling portion comprises a receptacle, into which a coupling piece of a ballasting cylinder can be inserted.

6. Mobile crane according to claim 3, further comprising at least one further counterweight element that can be stacked on the counterweight base plate and that has at least one recess through which the at least one coupling element projects in the deposited state, wherein the further counterweight element is arranged between the counterweight base plate and the carrier plate in the ballasted state,.

7. Mobile crane according to claim 3, wherein the at least one coupling element comprises a centering means, by means of which the counterweight device can be automatically positioned in an assembly position when it is lifted on the upper carriage, and/or a fastening means, by means of which the counterweight device can be releasably connected to the upper carriage in an assembly position and which has a bolt receptacle for producing a bolt connection to the upper carriage.

8. Mobile crane according to claim 1, wherein the second connections form axes of rotation for the suspension weights and are thus designed such that the suspension weights pivot about the axes of rotation relative to the carrier plate when the assembly unit is lifted and thus spread apart laterally by a defined distance.

9. Mobile crane according to claim 1, wherein the first connecting element comprise suspension bolts arranged on the carrier plate and hook elements arranged on the suspension weights, wherein the hook elements comprise a recess open to one side.

10. Mobile crane according to claim 1, wherein the carrier plate has cavities within which the first and second connecting elements are arranged in such a way that they do not project beyond the outer contour of the carrier plate in plan view.

11. Mobile crane according to claim 1, wherein the counterweight device is designed such that in the set-down state of the carrier plate the suspension weights connected thereto are arranged laterally next to the counterweight base plate.

12. Mobile crane according to claim 1, wherein two spaced-apart coupling elements are connected to the counterweight base plate and have a flat shape.

13. Counterweight device for a Mobile crane according to claim 1, further comprising at least one counterweight element stackable on the counterweight base plate.

14. Method for assembling the counterweight device on the upper carriage of a mobile crane according to claim 1, having the following steps: placing the counterweight base plate on a storage area of the undercarriage, by means of a boom of the mobile crane, lifting the assembly unit including the carrier plate and the suspension weights connected to it via slinging means of the suspension weights, placing the assembly unit on the counterweight base plate, and lifting the entire counterweight device via a ballasting device of the mobile crane to the upper carriage, by coupling at least one ballasting cylinder to at least one coupling element connected to the counterweight base plate and projecting through the carrier plate.

15. Method according to the claim 1 wherein the second connections form axes of rotation for the suspension weights and are thus designed such that the suspension weights pivot about the axes of rotation relative to the carrier plate when the assembly unit is lifted and thus spread apart laterally by a defined distance, and where the suspension weights spread apart laterally when the assembly unit is lifted, such that the assembly unit forms a widened receiving area for the counterweight base plate when spread open and can be set down on it, wherein the suspension weights are arranged next to the counterweight base plate during lowering and pivot towards it.

16. Mobile crane according to claim 3, wherein the ballasting device comprises at least one hydraulic ballasting cylinder; and wherein the carrier plate has at least one recess, through which the at least one coupling element protrudes in the deposited state.

17. Mobile crane according to claim 5, wherein the coupling piece can be inserted by rotating the upper carriage about its axis of rotation.

18. Mobile crane according to claim 6, wherein the counterweight plate and the at least one further counterweight element also form a jointly liftable second assembly unit.

19. Mobile crane according to claim 8, wherein the rotary movements are limited by a stop of the first connecting elements.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0050] Further features, details and advantages of the disclosure result from the following exemplary embodiments explained with the help of the figures. In the drawings:

[0051] FIG. 1: shows a side view of the mobile crane according to the disclosure according to an exemplary embodiment;

[0052] FIG. 2: shows the counterweight device according to the disclosure during set-up with a view of its rear side;

[0053] FIG. 3: shows the counterweight device in the set-up state with a view of its rear side;

[0054] FIG. 4: shows a plan view of the counterweight device in the set-up state;

[0055] FIG. 5: shows a plan view of an enlarged section of the connection area of a suspension weight;

[0056] FIG. 6: shows a side view of the connection area according to FIG. 5; and

[0057] FIG. 7: shows the set-up counterweight device 10 with the attached assembly unit 11 being lifted by means of sling ropes with a view of its rear side.

DETAILED DESCRIPTION

[0058] FIG. 1 shows a side view of an exemplary embodiment of the mobile crane 1 according to the disclosure in the form of a crawler crane. The mobile crane 1 has an undercarriage 2 with a crawler chassis and an upper carriage 4 mounted on the undercarriage 2 so that it can rotate about a vertical axis of rotation 3. The upper carriage 4 comprises a telescopic boom 6 mounted to luff about a horizontal axis and a counterweight arrangement also referred to as upper carriage ballast.

[0059] In this exemplary embodiment, the upper carriage ballast comprises a ballast frame 7, which is connected to the steel structure of the upper carriage 4 via bolt connections and can be removed from the upper carriage 4 for transport. Two hydraulic ballasting cylinders 8 are mounted on the ballast frame 7, the piston rods of which can be extended downwards and each have a coupling piece. A counterweight device 10 can be lifted from a storage area 5 to the upper carriage 4 via the ballasting cylinders 8 and connected to it. Conversely, the counterweight device 10 can be placed back on the storage area 5 by extending the ballasting cylinders 8 and loaded from there onto a transport vehicle using an auxiliary crane or the boom 6 of the mobile crane 1.

[0060] In this exemplary embodiment, the storage area 5 is formed by a hinged storage device at the rear of the undercarriage 2, which comprises two pivoting hinged parts on which the counterweight device 10 can be stored. However, the storage area could also be located on the top of the undercarriage 2 or on the floor, for example.

[0061] The counterweight device 10 comprises a counterweight base plate 20, on which one or more plate-shaped counterweight elements 22 can be stacked. In addition, a plurality of suspension weights 50 is provided, which are described below. This allows the upper carriage ballast to be configured variably and adapted to the desired application. In the exemplary embodiment shown here, a single further counterweight plate 22 is provided (apart from the carrier plate 40 described later). A side view looking at the rear of the counterweight device 10 is shown in FIG. 3.

[0062] The counterweight device 10 is coupled to the ballasting cylinders 8 via coupling elements 30 projecting vertically upwards from the counterweight base plate 20, which have coupling portions 32 at their upper ends for reversible coupling to the coupling pieces of the ballasting cylinders 8 as well as fastening means 36 for fastening the counterweight device 10 to the ballast frame 7. The alignment or positioning of the counterweight device 10 in an assembly position on the ballast frame 7 to establish the connection via the fastening means 36 is carried out via centering means 34 of the coupling elements 30. The centering means 34 and fastening means 36 can be seen in a side view in FIG. 1 (these protrude above the top plate or carrier plate 40 of the counterweight device 10).

[0063] As can be seen in FIG. 2, which shows the counterweight device 10 being set up with a view of its rear side, the counterweight device 10 comprises a carrier plate 40 that forms the upper end of the ballast stack comprising the counterweight base plate 20 and the further counterweight element 22. Additional counterweight elements in the form of suspension weights 50 are attached to the side of the carrier plate 40, in the exemplary embodiment discussed here one suspension weight 50 per side.

[0064] The suspension weights 50 are arranged such that they extend to the lower counterweight base plate 20 when the counterweight device 10 is fully assembled (i.e. set up). In particular, the height of the suspension weights 50 corresponds to the height of the ballast stack of the counterweight device 10.

[0065] According to the disclosure, the carrier plate 40 and the suspension weights 50 form a common (first) assembly unit 11, which can be transported and lifted together (in this respect, it can also be referred to as a transport and assembly unit 11). This means that only a single stroke is required to lift the carrier plate 40 and suspension weights 50 to the storage area 5.

[0066] The counterweight base plate 20 and the further counterweight element 22 placed thereon optionally also form a common (second) assembly unit 12. For this purpose, the coupling elements 30 can have slinging means (not shown here) (for example in the form of corresponding recesses to which chains or ropes can be attached) in order to be able to lift the lower or second assembly unit 12 via the coupling elements 30.

[0067] A possible exemplary embodiment of a storage device 5 of the undercarriage 2 is shown in FIG. 1. The central ballast, which can be assembled directly on the undercarriage 2 via fastening elements, is extended by a hinged holder for the counterweight device 10. Two pivot parts are hinged to the side cheeks of the central ballast and have support surfaces on their upper sides on which the counterweight device 10 can be placed.

[0068] To set up the counterweight device 10, the lower assembly unit 12, comprising the counterweight base plate 20 and the counterweight element 22 already placed on it, is first lifted from a transport vehicle (e.g. a low-loader) and placed on the storage area 5. The lift may be carried out by means of the boom 6 of the mobile crane 1 in self-set-up mode, but could of course also be carried out by an auxiliary crane.

[0069] The upper assembly unit 11, comprising the carrier plate 40 and suspension weights 50, which have also already been assembled and transported separately, is now set down on the lower assembly unit 12 (e.g., using the boom 6). The state shortly before setting down is shown in FIG. 2. It can be seen that the space between the suspension weights 50 and below the carrier plate 40 forms a receiving area 13 for the counterweight base plate 20 and counterweight element 22, in which the latter components are received in the set-up state (see FIG. 3).

[0070] As can be seen in FIG. 3, the coupling elements 30 connected to the counterweight base plate 20 have such a length that they protrude beyond the top of the carrier plate 40 in the set-up state. For this purpose, both the further counterweight element 22 and the carrier plate 40 have correspondingly shaped recesses through which the coupling elements 30 protrude. The coupling elements 30, which could also be referred to as connecting levers, are in particular one-piece sheet metal structures that have a flat basic shape and are connected to the counterweight base plate 20.

[0071] The directions up and down used here refer to the case where the counterweight base plate 20 (and the mobile crane 1) are standing on a level surface and the coupling elements 30 are aligned vertically.

[0072] FIG. 4 shows a plan view of the carrier plate 40 with the suspension weights 50 attached to it. The essentially slot-shaped recesses 44, in which the coupling elements 30 are arranged, can be seen running parallel to one another.

[0073] The coupling elements 30 serve both to pick up and lift the counterweight device 10 and to center it on and attach it to the ballasting device (or to the ballast frame 7). For this purpose, the coupling elements 30 have a coupling portion 32 at their end opposite the counterweight base plate 20 (see FIG. 2).

[0074] The coupling portion 32 comprises, in particular, an upwardly open, clamp-shaped recess 33 (see FIG. 4), into which a specially shaped (in particular mushroom-shaped) end or coupling piece of the corresponding ballasting cylinder 8 can enter laterally. In the final position, in which the counterweight device 10 can be safely lifted, the coupling pieces of the ballasting cylinders 8 are located in the center of the respective recesses 33, which, thanks to their shape, enable the counterweight device 10 to be lifted in a form-fitting manner by retracting the ballasting cylinders 8.

[0075] In the exemplary embodiment shown here, the ballasting cylinders 8 are coupled to the coupling elements 30 by rotating the upper carriage 4 about its axis of rotation 3. For this reason, the recesses 44 are widened in the center area to one side (to the left in FIG. 4) so that the coupling pieces of the ballasting cylinders 8 next to the coupling elements 30 can be moved downwards into the widened portions 45 of the recesses 44 until the coupling pieces are at the level of the recesses 33. Coupling can then be established by rotating the upper carriage 4. In the exemplary embodiment shown here, the widened portions 45 have a rectangular shape and are arranged slightly offset from one another (i.e. not at the same height in plan view) in order to take into account the circular path of the ballasting cylinders 8 when the upper carriage 4 rotates. Other shapes and arrangements of the recesses 45 are also conceivable.

[0076] After lifting the counterweight device 10 to the upper carriage 4 or ballast frame 7, the coupling elements 30 are bolted to the ballast frame 7. This relieves the ballasting cylinders 8 during crane operation. Therefore, the coupling elements 30 have fastening means 36 in the area of the coupling portions 32 (see FIGS. 1 and 3), that enable a stable connection of the counterweight device 10 to the ballast frame 7. The fastening means 36 are in particular designed as bolt receptacles through which corresponding fastening bolts can be inserted in the assembly position.

[0077] The coupling elements 30 may also comprise centering means 34 in the area of the fastening means 36 (see FIGS. 1 and 3), in the exemplary embodiment shown here in the form of a projection or mandrel projecting upwards and tapering in the longitudinal direction of the coupling element 30, via which the counterweight device 10 is brought into the desired mounting position when the ballasting cylinders 8 are retracted. The centering means 34 interact with counter-centering means not shown on the ballast frame 7 and ensure that the counterweight device 10 is automatically aligned when it is moved towards the ballast frame 7.

[0078] The suspension weights 50 are detachably attached to the carrier plate 40 via two connections 100, 200. A first suspension connection 100 is produced by means of first connecting elements 41, 51 and enables uncomplicated suspension of the suspension weights 50 on the carrier plate 40. For this purpose, the suspension weights 50 have lateral connecting plates 54 in the area of the end face facing the carrier plate 40, which form hook elements 51 in their front sections. The arrangement of the connecting plates 54 can be seen in the plan view of FIG. 4, while FIGS. 5 and 6 show a plan view and a side view of one of these connecting plates 54 in the connected state.

[0079] The hook elements 51 (=first connecting elements of the suspension weights 50) comprise downwardly open recesses 55, in which suspension bolts 41 (=first connecting elements of the carrier plate 40) are received, which are located in cavities 46 formed at the corners of the carrier plate 40 (see FIG. 4). The suspension weights 50 are hooked into the suspension bolts 41 of the carrier plate 40 via the hook elements 51, thereby forming the first suspension connections 100. In principle, it would also be conceivable to provide upwardly open hook elements on the carrier plate 40 and suspension bolts on the suspension weights 50.

[0080] In addition, the carrier plate 40 and the suspension weights 50 have second connecting elements 42, 52, 53 for forming a second connection 200, which secure the first suspension connection 100 and prevent unintentional unhooking of the suspension weights 50. In the exemplary embodiment shown here, the second connecting elements 42, 52, 53 comprise bolt receptacles 42 formed on the carrier plate 40 in the region of the cavities 46 and bolt receptacles 52 also formed on the connecting plates 54, through which corresponding bolts 53 are inserted as soon as the bolt receptacles 42, 52 overlap.

[0081] The cavities 46 are provided on the carrier plate 40 such that the connecting plates 54 do not protrude laterally beyond the outer contour of the carrier plate 40, i.e. the connecting plates 54 are located inside the cavities 46 in plan view.

[0082] The second connections 200 or bolt connections not only increase safety when lifting the assembly unit 11 or during crane operation, for example in the event of a sudden load drop, but also enable the assembly unit 11 according to the disclosure to be lifted above the suspension weights 50, as shown in the side view of FIG. 7. For this purpose, the suspension weights 50 have corresponding slinging means 58 on their sides spaced apart from the carrier plate 40, to which a sling rope 60 or a sling chain of a hoist can be attached.

[0083] Without the second connections 200, the suspension connections 100 would simply come loose when the suspension weights 50 are lifted. The first and second connecting elements 41, 42, 51, 52, 53 are designed in such a way that they can safely absorb and transmit the forces occurring during the lift.

[0084] As can be seen in FIG. 6, the openings 55 of the hook elements 51 have a greater width than the suspension bolts 41 received therein. This defined clearance makes it easier to attach the suspension weights 50. A pivot movement is achieved by a larger bore 52

[0085] This deliberate pivot movement of the suspension weights 50 makes it easier to place the upper assembly unit 11 on the lower assembly unit 12 (see FIG. 2). During the lift of the assembly unit 11, the suspension weights 50 are pivoted apart or spread apart by a defined distance due to the mobility described above. This widens the receiving area 13 between the suspension weights 50, making it easier to insert the lower assembly unit 12 into this receiving area 13.

[0086] Since the carrier plate 40 can also be used for certain applications without the suspension weights 50, it also has corresponding slinging means 48 on its sides. In principle, the assembly unit 11 could also be lifted over these slinging means 48 of the carrier plate 40. In this case, however, the advantage of spreading the suspension weights 50 apart as described above would not arise.

[0087] The ballast elements 20, 22, 40, 50 can be designed either as a filled box construction or as a cast ballast. Optionally, however, said ballast elements 20, 22, 40, 50 are made of an inexpensive and environmentally friendly box construction into which, for example, metal parts are inserted during manufacture and the gaps are filled with a filling compound. However, these have a lower specific weight, meaning that an additional volume of counterweight is required for many applications in order to generate the necessary torque for stability. This additional weight is provided by the suspension weights 50.

[0088] Finally, it should be mentioned that operating personnel may be required to place the counterweight package formed by the assembly unit 11 on the already prepared counterweight package of the assembly unit 12 and to make the connections between them. These steps can be carried out from a comfortable and safe position on the undercarriage 2. It is only necessary to enter the exposed counterweight device 10 itself to unhook or hang the sling ropes 60. However, this does not usually require a great deal of effort. If climbing onto the counterweight device 10 is to be avoided altogether, folding ladders can be used, for example.

[0089] FIGS. 1-7 are drawn to scale, although other relative dimensions may be used, if desired.

LIST OF REFERENCE NUMERALS

[0090] 1 Mobile crane [0091] 2 Undercarriage [0092] 3 Axis of rotation [0093] 4 Upper carriage [0094] 5 Storage area [0095] 6 Boom [0096] 7 Ballast frame [0097] 8 Ballasting cylinder [0098] 10 Counterweight device [0099] 11 (Upper) assembly unit [0100] 12 Second (lower) assembly unit [0101] 13 Receiving area [0102] 20 Counterweight base plate [0103] 22 Counterweight element [0104] 30 Coupling element [0105] 32 Coupling portion [0106] 33 Receptacle [0107] 34 Centering means [0108] 36 Fastening means [0109] 40 Carrier plate [0110] 41 First connecting element (suspension bolt) [0111] 42 Second connecting element (bolt receptacle) [0112] 44 Recess [0113] 45 Widened portion of the recess [0114] 46 Cavity [0115] 48 Slinging means [0116] 50 Suspension weight [0117] 51 First connecting element (hook element) [0118] 52 Second connecting element (bolt receptacle) [0119] 53 Bolt [0120] 54 Connection plate [0121] 55 Recess [0122] 56 Slinging means [0123] 58 Slinging means [0124] 60 Sling part [0125] 100 First connection (suspension connection) [0126] 200 Second connection