Mobile Crane Having A Counterweight Device

Abstract

The present invention relates to a mobile crane having a travelable undercarriage, a superstructure rotatably supported on the undercarriage, and a counterweight device couplable to the superstructure, wherein the counterweight device comprises a carrier plate on which one or more counterweight elements can be stacked, and at least one connection element extending substantially perpendicular to the carrier plate for coupling the carrier plate to the superstructure.

Claims

1. A mobile crane having a travelable undercarriage, a superstructure rotatably supported on the undercarriage, and a counterweight device couplable to the superstructure wherein the counterweight device comprises a carrier plate on which one or more counterweight elements can be stacked, and at least one connection element extending substantially perpendicular to the carrier plate for coupling the carrier plate to the superstructure, wherein the at least one connection element has a placement area on which a counterweight element can be placed such that a weight force of the counterweight element is introduced into the at least one connection element and not into the carrier plate, wherein the at least one connection element is formed in one piece.

2. A-The mobile crane in accordance with claim 1, wherein the at least one connection element is formed as a one-piece metal sheet construction having a substantially flat form, with two placement areas at oppositely disposed sides of the at least one connection element.

3. The mobile crane in accordance with claim 1, wherein the at least one connection element is fixedly connected to the carrier plate with the at least one connection element welded to the carrier plate on one side.

4. The mobile crane in accordance with claim 1, wherein the at least one connection element has a connection region at an end oppositely disposed the carrier plate via which the at least one connection element is coupled with the superstructure with the at least one connection element having a smaller width in a region of the connection region than in a region of a connection to the carrier plate.

5. The mobile crane in accordance with claim 4, wherein a ballasting device is provided at the superstructure by which the counterweight device can be raised and placed down, and can be raised from and placed on a placement region of the undercarriage, with the ballasting device comprising at least one hydraulic ballasting cylinder that can be brought into releasable engagement with the connection region of one or more of: (a) the at least one connection element (b) or a ballast frame connectable to the superstructure via a fastener.

6. The mobile crane in accordance with claim 5, wherein the connection region comprises a recess into which a coupling piece of the at least one hydraulic ballasting cylinder can travel by rotating the superstructure about an axis of rotation with the coupling piece being lockable in the recess.

7. A—The mobile crane in accordance with claim 6, further comprising a counterweight base plate having a recess through which the at least one connection element projects in a placed down state, with the counterweight base plate configured to be placed ono a placement area of the at least one connection element such that the counterweight base plate does not contact the carrier plate in the placed down state.

8. The mobile crane in accordance with claim 7, further comprising an intermediate counterweight element configured to be placed on the carrier plate between the carrier plate and the counterweight plate, the intermediate counterweight element having a recess through which the at least one connection element projects in the placed down state with the intermediate counterweight element lying on the carrier plate and introducing at least a portion of a weight force of the intermediate counterweight element into the carrier plate.

9. The mobile crane in accordance with claim 7, further comprising at least one plate-like counterweight element configured to be placed or stacked on the counterweight base plate and having a recess through which the at least one connection element projects in the placed down state.

10. The mobile crane in accordance with claims 9, wherein the recess of the at least one plate-like counterweight element is configured such that a coupling piece of the at least one hydraulic ballasting cylinder can be positioned within the recess of the at least one plate-like counterweight element beside the connection region of the at least one connection means (30) element and can be traveled into the connection region by rotating the superstructure, wherein the recess of the at least one plate-like counterweight element has a stop which the coupling piece abuts in an assembly position in which the counterweight device can be raised by the at least one ballasting cylinder.

11. The mobile crane in accordance with claim 1, wherein the at least one connection element comprises at least one stop element for fastening a stop means of lifting equipment for raising the carrier plate with the stop element comprising a recess of the at least one connection element.

12. The mobile crane in accordance with claim 1, wherein the carrier plate comprises at least two mutually spaced apart connection means that are one or more of: (a) arranged rotated with respect to one another or (b) at a common distance from a center of gravity of the carrier plate.

13. The mobile crane in accordance with claim 1, wherein the carrier plate comprises at least one centering means and is configured to be placed on a placement region of the undercarriage with the placement region having at least one corresponding counter-centering means configured to be brought into engagement with the centering means of the carrier plate for positioning of the carrier plate on the undercarriage.

14. The mobile crane in accordance with claim 1, wherein the carrier plate together with the at least one connection element has an axially symmetrical structure and/or the carrier plate has a swept shape.

15. The mobile crane in accordance with claim 1, further comprising an upper and plate-like counterweight element having at least one force introduction means arranged and configured such that on the raising and pressing of the counterweight device on the superstructure by means of a ballasting device of the mobile crane, the counterweight device is supported on the at least one force introduction means and the a force flow from the force introduction means into the at least one connection element substantially does not take place via the carrier plate, with the upper counterweight element having at least one fastening means for a direct fastening of the upper counterweight element to the superstructure.

16. The mobile crane in accordance with claim 1, wherein the at least one connection element has at least two placement areas spaced apart from one another along a longitudinal axis of the at least one connection element and on which a respective counterweight element can be placed such that a weight force of the counterweight element is introduced into the at least one connection element and not into the carrier plate or into a counterweight element disposed thereunder.

17. The mobile crane in accordance with claim 16, wherein each of the placement areas is arranged at a different distance from a center plane of the at least one connection element and the at least one connection element has a width reducing step-wise.

18. A counterweight device for a mobile crane in accordance with claim 1.

19. A set comprising: a counterweight device in accordance with the claim 18; a counterweight base plate in accordance with claim 7; and one or more of: (a) at least one further counterweight element in accordance with claim 10 or (b) an upper counterweight element in accordance with claim 14.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Further features, details, and advantages of the invention result from the embodiment explained in the following with reference to the Figures. There are shown:

[0048] FIG. 1: the mobile crane in accordance with the invention in accordance with an embodiment in a side view;

[0049] FIG. 2: the carrier plate with connection means without counterweight elements in a perspective view;

[0050] FIG. 3: a perspective sectional view through the counterweight device in the region of a connection means with counterweight elements stacked on in accordance with the first embodiment; and

[0051] FIG. 4: a lateral sectional view through a connection means of the counterweight device with counterweight elements stacked on in accordance with a second embodiment.

DETAILED DESCRIPTION

[0052] An embodiment of the mobile crane 10 in accordance with the invention in the form of a crawler crane is shown in a side view in FIG. 1. The mobile crane 1 has an undercarriage 12 having a crawler chassis and a superstructure 14 supported on the undercarriage 12 rotatable via a slewing gear about a vertical axis of rotation 13. The superstructure 14 comprises a telescopic boom 16 supported luffably about a horizontal axis and a counterweight arrangement also called superstructure ballast.

[0053] The superstructure ballast in this embodiment comprises a ballast frame 21 that is connected to the steel structure of the superstructure 14 via pin connections and that can be removed from the superstructure 14 for transport. Two hydraulic ballasting cylinders 23 whose piston rods can be downwardly extended are received at the ballast frame 21. A counterweight device 20 can be lifted from a placement region at the superstructure 14 and can be connected thereto via the ballasting cylinders 23. In this embodiment, the placement region is formed by a foldable placement device 18 in the rear of the undercarriage 12, with the placement region also being able to be located at an upper side of the undercarriage or on the ground. Conversely, the counterweight device 20 can be placed down on the placement device 18 again via an extension of the ballasting cylinders 23 and can be loaded onto a transport vehicle from there, optionally by means of an auxiliary crane or the boom 16 of the mobile crane 10 itself.

[0054] The counterweight device 20 comprises a carrier plate 22 on which a plurality of counterweight elements 24, 25, 26, 28 can be stacked. The superstructure ballast can thereby be variably configured and can be adapted to the desired deployment. The coupling of the counterweight device 20 with the superstructure 14 or with the ballasting cylinders 23 takes place via connection means 30 that project perpendicularly upwardly from the carrier plate 20 and that have connection regions 34 for a reversible coupling with the ballasting cylinders 23 at their upper ends.

[0055] A preferred embodiment of the carrier plate 22 together with connection means 30 is shown perspectively in FIG. 2. A section through one of the connection means 30 and the carrier plate 22 with counterweight elements 24, 25, 26, 28 stacked thereon in accordance with an embodiment is shown in FIG. 3.

[0056] The connection means 30 are metal sheet constructions that are produced in one piece and that are fastened, in particular welded, to the upper side of the carrier plate 22. The weld connection is marked by the reference numeral 31 in FIG. 2. The connection means 30, that could also be connection struts or simply struts, have a flat basic shape that tapers upward to a connection region 34 from its widest extent in the connection region having the carrier plate 22. In the embodiment shown here, the connection means 30 more precisely have a lower region that is substantially trapezoidal, that merges into a straight region or into a region having a constant width, but that has various recesses 35, 36 which will be looked at further below.

[0057] The indications of direction “upward” and “downward” used herein relate to the case that the carrier plate 22 (and the mobile crane 10) stand on a level base. In this case, the connection means 30 extend perpendicularly upwardly from the carrier plate 22.

[0058] The trapezoidal regions of the connection means 30 each have two placement areas 32 that each form a flat, horizontal surface (and can together be called a “placement area” of the respective connection means 30). The bottommost counterweight element 24 of the counterweight arrangement 20 in accordance with the embodiment shown here, called a counterweight base plate 24 in the present case, lies on the four placement areas 32 of the connection means 30 in the placed down state and introduces its weight force directly into the connection means 30 via these contact surfaces. Since all the further counterweight elements 26, 28 arranged thereabove lie or are stacked on the counterweight base plate 24 and every further counterweight plate 26, 28 is supported on the respective counterweight plate 24, 26 disposed thereunder, its total weight does not weigh on the carrier plate 22, but rather on the connection means 30.

[0059] The counterweight base plate 24 preferably does not contact the carrier plate 22 at all, i.e. there is a spacing therebetween. Provision can naturally also be made that the counterweight base plate 24 is supported at or contacts the carrier plate 22 to a certain extent, but without introducing a significant portion of its weight force into the carrier plate 22. It is likewise conceivable that the placement areas 32 do not extend or do not exclusively extend horizontally, but are e.g. inclined.

[0060] The weld connection 31 between the connection means 30 and the carrier plate 22 is relieved by the support on the placement areas 32 since it substantially only has to take up the weight force of the carrier plate 22 itself.

[0061] The counterweight base plate 24 preferably has especially machined surfaces, that lie on the placement areas 32 of the connection means 30 in the placed down state, at its lower side at points complementary to the placement areas 32.

[0062] In addition, as shown in the embodiment in accordance with FIG. 3, a comparatively small or light intermediate plate 25 (=intermediate counterweight element) can be provided that is arranged between the counterweight base plate 24 and the carrier plate 22 and lies on the latter. This can be advantageous on a special equipment state of the mobile crane 10 and can optionally be taken along or not taken along for the road travel. The loads induced by the small intermediate plate 25 are to be removed via the weld connection 31.

[0063] Alternatively, the counterweight base plate 24 could also be configured such that it utilizes the space present even over a larger volume and has a greater mass. In every case, however, a sufficient distance from the carrier plate 22 is preferably present in order not to introduce any loads from the counterweight base plate 24 into the carrier plate 22.

[0064] Since the connection means 30 do not consist of a plurality of connected parts, but are rather formed in one piece, weld connections that are complicated to manufacture and that have correspondingly high demands do not have to be provided.

[0065] The carrier plate 22 in particular has the following objectives:

[0066] positioning the connection means 30 for the equipping of the counterweight device 20 by the ballasting cylinders 23 on the superstructure 14;

[0067] positioning the carrier plate 22 on the undercarriage 12, for example on a placement device 18 such as shown in FIG. 1. The connection means or coupling pieces of the ballasting cylinders 23 can thus engage into the connection regions 34 of the connection means 30. This positioning has to take place very precisely since it in particular takes place by means of a rotational movement of the superstructure 14 about the axis of rotation 13 on the undercarriage 12;

[0068] the carrier plate 22 furthermore has to hold the connection means 30 securely in position, even when transverse forces occur. Such transverse forces can occur, for example, when the ballasting cylinders 23 rotate into the connection regions 34 and abut or rub at or in them. The transverse forces can also occur with slanted positions due to the weight forces.

[0069] The counterweight base plate 34 has corresponding, in particular slit-like, recesses 241 through which the connection means 30 project. The counterweight plates 26 disposed thereabove and the topmost counterweight plate 28 likewise have corresponding recesses 261, 281. The connection means 30 are preferably completely surrounded by all the counterweight elements 24, 26, 28.

[0070] The optionally provided intermediate plate 25 also has corresponding recesses 251 and preferably surrounds the connection means 30.

[0071] The connection regions 34 at the upper ends of the connection means 30 comprise clip-like recesses 35 into which the especially shaped ends or coupling pieces of the ballasting cylinders 23 travel at the side. In the assembly position, the coupling pieces are located completely within the recesses 35 that due to their shape enable a shape matched raising of the counterweight arrangement 20 by retracting the ballast cylinders 23 since the coupling pieces cannot travel upwardly out of the recesses 35, but rather abut them.

[0072] The coupling of the ballasting cylinders 23 with the connection means 30 in particular takes place by a rotation of the superstructure 14 about its axis of rotation 13. The recesses 261, 281 of at least the counterweight elements disposed at the height of the connection regions 34 (they are the topmost two counterweight plates 26, 28) in FIG. 3 are therefore not formed as slit-like, but are rather widened in the direction of rotation of the superstructure 14 so that the ballasting cylinders 23 can be retracted downwardly beside the connection means 30 into the recesses 261, 281 until the coupling pieces are at the level of the recesses 35 of the connection regions 34. A coupling can then be established by rotating the superstructure 14.

[0073] To enable this circular movement of the ballasting cylinders 23 or a corresponding coupling, the connection means 30 are not in parallel with one another, but adopt an angle with one another. More specifically, the planes in which the connection means 30 are disposed run apart from one another in a direction directed away from the axis of rotation 13 of the superstructure.

[0074] The connection means 30 are in particular welded onto the carrier plate 22 without any special projections or setbacks by the weld connection 31. By this

[0075] the relative position of the two connection means 30 with respect to one another is defined so that the recesses 241, 251, 261, 281 of the further counterweight plates 24, 25, 26, 28 can correctly take up the two connection means 30;

[0076] the position of the placement areas 32 is defined to take up the machined surfaces at the counterweight base plate 24 at defined points; and

[0077] the correct positioning of the connection regions 34 in relation to the carrier plate 22 is ensured at defined points.

[0078] So that the coupling pieces of the ballasting cylinders 23 are not moved through the connection regions 34, but rather reach their correct assembly position, the recesses 261, 281 are preferably configured such that their walls form corresponding mechanical stops for the coupling pieces. An overrun of the ballasting cylinders 23 is thereby effectively prevented.

[0079] In the assembly position, the ballasting cylinders 23 and the connection means 30 can preferably be reversibly locked with one another.

[0080] The connection means 30 can have chamfered edges or bevels 38 at the upper side to facilitate a threading of the counterweight elements 24, 26, 28.

[0081] In the embodiment shown here, the connection means 30 additionally have mounts 38 for connection to a fall protection in the connection regions 34 (or at the lower sides of the recesses 35).

[0082] The connection means 30 have recesses 39 laterally at the straight (upper) regions that serve as stop elements for fastening stop means (e.g. a chain or a rope) of a crane for handling the carrier plate 22.

[0083] Gray iron can be provided as the material for the counterweight plates 24, 25, 26, 28 and/or for the carrier plate 22.

[0084] The cutout 50 in the lower side of the carrier plate 22 to be recognized in FIG. 3 centrally below the connection means 30 serves as a centering means for the correct positioning of the carrier plate 22 on the placement region of the undercarriage 12. The latter preferably has corresponding projections as counter-centering means that travel into the cutouts 50. The connection means 30 are thereby always in their correct position for equipping the counterweight device 20 that is in particular known to the crane control.

[0085] The cutouts 50 can extend, as can be seen in FIG. 3, through the whole carrier plate 22 and can be covered by a plate 52. Alternatively, the cutouts 50 could also end within the carrier plate 22. The centering means 50 can naturally be provided at a different point than below the connection means 30.

[0086] To enable a positioning of the carrier plate 22 at different distances from the axis of rotation 13 (e.g. in combination with ballasting cylinders 23 adjustable in their relative position to the axis of rotation 13 of the superstructure), more than two centering means 50 can be provided, such as described, for example, in DE 10 2015 013 488 A1.

[0087] As can be recognized in FIG. 3, the topmost counterweight plate 28 can have a series of fastening means 62 that are configured as cast parts having recesses for establishing pin connections to the ballast frame 21 in the present embodiment. As required, the topmost counterweight plate 28 can thereby be directly connected to the steel construction of the superstructure 14, for example to travel the mobile crane 10 with a reduced counterweight. The remaining counterweight device 22, 24, 25, 26, 30 can still be removed from the superstructure 14.

[0088] Provision can furthermore optionally be made that the topmost two counterweight plates 26, 28 can be releasably lockable with one another so that not only the topmost, but rather both counterweight plates 26, 28 can remain at the superstructure 14.

[0089] The fastening means 62 furthermore comprise contact points that act as force introduction means 60 (cf. FIG. 3). They can cooperate with corresponding contact elements or contact points at the ballast frame 21. The total counterweight device 20 is supported at the force introduction means 60 when the ballasting cylinders 23 press them against the ballast frame 21 to establish the connection between the counterweight device 20 and the superstructure 14. As described above, huge forces can occur here. A force flow (shown by the arrows 70 in FIG. 3) results on the pressing on through the counterweight elements 24, 26, 28 and directly into the connection means 30 via the placement areas 32 due to the design in accordance with the invention and the arrangement of the carrier plate 22, connection means 30, their placement areas 32 and the force introduction means 60. Said connection means 30 conduct the forces further in themselves and via the connection regions 34 and the ballasting cylinders 23 back into the ballast frame 21 or superstructure 14. The weld connections 31 between the carrier plate 22 and the connection means 30 are outside this force flow 70.

[0090] The weld connections 31 between the carrier plate 22 and the connection means 30 therefore only “see” the weight forces of the carrier plate 22 itself and optionally the relatively light intermediate plate 25 and therefore do not have to be designed for the huge forces that otherwise occur.

[0091] It is conceivable in principle that the ballasting cylinders 23 can hold the counterweight device 20 at the superstructure 14 during crane operation and can optionally be locked (e.g. mechanically and/or hydraulically). However, connection elements, not shown in any more detail here, are preferably provided at the connection means 30 and corresponding counter-connection elements are provided at the ballast frame 21 via which the connection can be established, for example in the form of pin connections.

[0092] The carrier plate 22 and the counterweight elements 24, 25, 26, 28 in the embodiment shown here are formed in one piece and slightly curved for swung.

[0093] The topmost counterweight element 28 (and optionally also the counterweight element 26 arranged thereunder) can have cutouts 80 at the sides that enable a hooking in of hang-in ballast elements (=hang-in connection means). In the embodiment shown in FIG. 3, the cutouts 80 are formed as T grooves.

[0094] A second embodiment of the counterweight device 20 in accordance with the invention is shown in FIG. 4. A section through a connection means 30 can be seen onto which a plurality of counterweight elements 24, 26 have been placed. In contrast to the first embodiment, the connection means 30 here not only has a placement area 32 for the bottommost counterweight element 24, but also a plurality of placement areas 32 on which the remaining counterweight elements 26 lie. In other words, every counterweight element 24 lies on its own placement area 32 of the connection means 30 so that it does not introduce its weight force into the counterweight element 26, 324 disposed thereunder (or into the carrier plate 22), but rather directly into the connection means 30 (or into the connection means 30). The connection means 30 has a step-like structure, with the upper sides of these “steps” forming the respective placement areas 32. The width of the connection means 30 thus reduces step-wise upwardly toward the connection region 34 starting from the carrier plate 22.