MOBILE CRANE COMPRISING A DEVICE FOR FACILITATING OR FULLY AUTOMATICALLY CARRYING OUT A RAISING AND/OR SETTING-DOWN PROCESS OF A DERRICK BOOM, AND CORRESPONDING METHOD

Abstract

The present disclosure relates to a mobile crane, which comprises a superstructure, a main boom, which extends away from the superstructure and is arranged so as to be pivotable thereon, a derrick boom, which extends away from the superstructure and is arranged so as to be pivotable thereon, and a winch assembly, wherein the winch assembly comprises a main-boom winch for actuating the main boom and a derrick-boom winch for actuating the derrick boom. The mobile crane is characterised by an assistance apparatus for facilitating or fully automatically carrying out a raising and/or setting-down process of the derrick boom, which apparatus is designed to actuate the main boom and the derrick boom, such as the main-boom winch and the derrick-boom winch, at the same time.

Claims

1. A mobile crane, comprising a superstructure, a main boom, which extends away from the superstructure and is arranged so as to be pivotable thereon, a derrick boom, which extends away from the superstructure and is arranged so as to be pivotable thereon, and a winch assembly on the superstructure and/or on the derrick boom, wherein the winch assembly comprises a main-boom winch for actuating the main boom and a derrick-boom winch for actuating the derrick boom, wherein an assistance apparatus for facilitating or fully automatically carrying out a raising and/or setting-down process of the derrick boom, which assistance apparatus is designed to actuate the main boom and the derrick boom at the same time.

2. The mobile crane according to claim 1, further comprising: a force-measuring unit for determining a force of a support strand from the derrick boom and/or a force of a support strand from the main boom, wherein the assistance apparatus actuates the main-boom winch and/or the derrick-boom winch on the basis of values of the support-strand force for the derrick boom and/or the support-strand force for the main boom that are determined by the force-measuring unit.

3. The mobile crane according to claim 2, wherein, in a raising process of the derrick boom, the assistance apparatus is also designed to actuate the derrick boom in a raising direction and to simultaneously actuate the main boom in a lowering direction.

4. The mobile crane according to claim 3, wherein, in a setting-down process of the derrick boom, the assistance apparatus is also designed to actuate the derrick boom in the lowering direction and to simultaneously actuate the main boom in the raising direction.

5. The mobile crane according to claim 1, wherein the main boom is set down on the ground during the raising and/or setting-down process of the derrick boom.

6. The mobile crane according to claim 3, wherein, during the raising and/or setting-down process, the derrick boom is tensioned between the support strand of the main boom and the support strand of the derrick boom, such that the derrick boom is tensioned between a cable that can be controlled by the main-boom winch and a cable that can be controlled by the derrick-boom winch and/or in that the derrick boom can be pivoted by activating the main-boom winch in a first direction and by activating the derrick-boom winch in a second direction opposite the first direction.

7. The mobile crane according to claim 6, wherein, during a raising process, the assistance apparatus is also designed to pretension the support strand of the main boom when the derrick boom pivots in the raising direction, when the derrick boom passes through a vertical position, such that after passing through the vertical position, the derrick boom does not fall against a slack support strand of the main boom.

8. The mobile crane according to claim 7, wherein, during a setting-down process, the assistance apparatus is also designed to pretension the support strand of the derrick boom when the derrick boom pivots in the lowering direction, such that after passing through the vertical position, the derrick boom does not fall against a slack support strand of the derrick boom.

9. The mobile crane according to claim 1, further comprising a user interface for activating the assistance apparatus, wherein the user interface comprises a lever, excursion of which influences a speed of movement of the derrick boom when it is raised and/or set down.

10. The mobile crane according to claim 9, wherein the user interface comprises a lever that can be moved out of a central position in two directions, wherein moving the lever out of the central position in one of the two directions results in the derrick boom being subjected to a raising process and moving the lever out of the central position in the other of the two directions results in the derrick boom being subjected to a setting-down process.

11. A method for facilitating or fully automatically carrying out the raising and/or setting-down process of claim 1, wherein, in the method: a main boom a derrick boom are actuated at the same time by the assistance apparatus.

12. The method according to claim 11, wherein during the raising and/or setting-down process, the derrick boom is tensioned between a support strand of the main boom and a support strand of the derrick boom, and a main-boom winch and/or a derrick-boom winch is actuated by the assistance apparatus on the basis of a support-strand force for the derrick boom and/or a support-strand force for the main boom, to keep the support strand of the main boom and/or the support strand of the derrick boom at a predetermined tension value, such that it is possible to correctly wind it up onto the main-boom winch and/or the derrick-boom winch.

13. The method according to claim 11, wherein the derrick boom is tensioned between a cable that can be controlled by the main-boom winch and a cable that can be controlled by the derrick-boom winch and/or wherein the derrick boom can be pivoted by activating the main-boom winch in a first direction and by activating the derrick-boom winch in a second direction opposite the first direction.

14. The method according to claim 12, wherein, during a raising process, when the derrick boom pivots in the raising direction, the support strand of the main boom is pretensioned by the assistance apparatus such that after passing through the vertical position, the derrick boom does not fall against a slack support strand of the main boom.

15. The method according to claim 12, wherein, during a setting-down process, when the derrick boom pivots in the lowering direction, the support strand of the derrick boom is pretensioned by the assistance apparatus such that after passing through the vertical position, the derrick boom does not fall against a slack support strand of the derrick boom.

16. The mobile crane according to claim 2, wherein the support strand of the main boom and/or of the derrick boom exceeds a predetermined tension value in order for it to be possible to correctly wind it up onto the main-boom winch and/or the derrick-boom winch.

17. The mobile crane according to claim 3, wherein the assistance apparatus is designed to actuate the derrick-boom winch in the raising direction and to actuate the main-boom winch in the lowering direction.

18. The mobile crane according to claim 4, wherein the assistance apparatus is designed to actuate the derrick-boom winch in the lowering direction and to actuate the main-boom winch in the raising direction.

19. The mobile crane according to claim 9, wherein no excursion of the user interface lever results in the derrick boom stopping.

20. The method according to claim 14, wherein the derrick boom passes through a vertical position.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0045] Further features and details of the disclosure are clear from the following description of the figures, in which:

[0046] FIG. 1 is a side view of a lifting device comprising a main boom set down on the ground and a derrick boom that is in a raising or setting-down process, and

[0047] FIG. 2 is a side view of a lifting device comprising a main boom set down on the ground and a derrick boom that is in its raised position.

DETAILED DESCRIPTION

[0048] FIG. 1 is a side view of a mobile crane 1, on the superstructure 2 of which a main boom 3 and a derrick boom 4 are arranged. Here, the derrick boom 4 is arranged above the main boom 3, which is lying on the ground 7, and is pivoted backwards relative thereto.

[0049] Proceeding from a winch assembly fastened to the mobile crane 1, a support strand 6 of the derrick-boom winch extends to the top of the derrick boom 4, wherein the support strand 6 is guided over the A frame 9. By activating the derrick-boom winch, the derrick boom 4 can be set into a steeper position from an approximately horizontal orientation (in the direction of the arrow B) and can also be pivoted beyond its vertical position. If, however, the derrick boom 4 exceeds its vertical orientation and the weight is transferred backwards, the support strand 6 of the derrick boom 4 can no longer provide support.

[0050] In order to prevent the derrick boom from falling backwards in an uncontrolled manner, the top of the derrick boom 4 is connected to the top of the main boom 3 by a second support cable 5, i.e. the main-boom support strand, the length of which can be controlled by the main-boom-adjusting winch.

[0051] The two support strands 5, 6 ensure that the derrick boom can be tensioned in opposite directions, such that, when the derrick boom passes through the vertical orientation, the load change from one support strand to the other support strand can be carried out without this resulting in uncontrolled movement of the derrick boom.

[0052] Accordingly, even when moving the derrick boom in direction A (starting from a derrick boom 4 that is directed backwards), it can be provided that the boom passing through the vertical orientation does not result in it collapsing in an uncontrolled manner.

[0053] FIG. 2 is a side view showing a derrick boom in its final operating position. Here, the derrick boom is directed backwards and an additional weight can be added thereto via a corresponding stay 8, which weight acts as an additional counterweight for a load suspended from the main boom when heavy loads are to be lifted.

[0054] In the following, the process of raising the derrick boom will be described in greater detail.

[0055] The main boom 3, comprising a luffing boom that is possibly mounted thereon, is lying on the ground 7. The derrick boom 4 is in a defined angular range above the main boom 3. The connections between the derrick boom 4 and the superstructure 2 or the main boom 3 are pre-existing and may also comprise retaining rods, for example.

[0056] According to the disclosure, it may be provided that the machine operator activates just one operating lever of a user interface in the raising direction, such that the assistance apparatus controls both the derrick-boom-adjusting winch in the raising direction and the main-boom-adjusting winch in the lowering direction. It may be provided here that the speed is dependent on the extent of the excursion of the operating lever.

[0057] The support-strand forces of the main boom 3 and the derrick boom 4, which are determined by the force-measuring unit for determining the force of the support strand 6 from the derrick boom 4 and/or the force of the support strand 5 from the main boom 3, are processed by the assistance apparatus such that the derrick boom 4 is kept within an optimal force range. As a result, the derrick boom 4 is tensioned and the situation in which the derrick boom 4 can fall against a slack main-boom support strand 5 does not occur in the region of the vertical position of the derrick boom 4.

[0058] Once the derrick boom 4 has reached its position for the operation of the crane, the process of raising the derrick boom 4 is stopped by the crane controller.

[0059] Furthermore, in the following, the process of setting down the derrick boom 4 will be described in greater detail. The main boom 3, comprising a luffing boom that is possibly mounted thereon, is lying on the ground 7. In its regular operating position for operation of the crane, the derrick boom 4 is directed backwards.

[0060] According to the disclosure, it may be provided that the machine operator activates the derrick-boom operating lever in the setting-down direction.

[0061] The assistance apparatus controls both the derrick-boom-adjusting winch in the lowering direction and the main-boom-adjusting winch in the raising direction at the same time, wherein the speed may be dependent on the extent of the excursion of the operating lever. The support-strand forces 5, 6 of the main boom 3 and the derrick boom 4, which are processed by the force-measuring unit, are kept within an optimal range by the assistance apparatus, such that the derrick boom 4 is tensioned and cannot fall against a slack derrick-boom support strand 6 in the region of the vertical position of the derrick boom 4.

[0062] Once the derrick boom 4 has been moved far enough forward that the support strand 5 between the derrick boom 4 and the main boom 3 can be disconnected, the machine operator stops the setting-down process by bringing the operating lever into the neutral position.

[0063] After disconnecting the support strand that can be controlled by the main-boom winch, the derrick boom can then be set down on the ground by the derrick-boom winch being accordingly actuated.

[0064] Here, it may typically be provided that, before setting the derrick boom down on the ground, the main boom is unbolted from the superstructure, such that it is possible to continue to move the derrick boom towards the ground.

[0065] FIGS. 1-2 are drawn to scale, although other relative dimensions may be used if desired. Further, FIGS. 1-2 show example configurations with relative positioning of the various components. If shown directly contacting each other, or directly coupled, then such elements may be referred to as directly contacting or directly coupled, respectively, at least in one example. Similarly, elements shown contiguous or adjacent to one another may be contiguous or adjacent to each other, respectively, at least in one example. As an example, components laying in face-sharing contact with each other may be referred to as in face-sharing contact. As another example, elements positioned apart from each other with only a space there-between and no other components may be referred to as such, in at least one example. As yet another example, elements shown above/below one another, at opposite sides to one another, or to the left/right of one another may be referred to as such, relative to one another. Further, as shown in the figures, a topmost element or point of element may be referred to as a “top” of the component and a bottommost element or point of the element may be referred to as a “bottom” of the component, in at least one example. As used herein, top/bottom, upper/lower, above/below, may be relative to a vertical axis of the figures and used to describe positioning of elements of the figures relative to one another. As such, elements shown above other elements are positioned vertically above the other elements, in one example. As yet another example, shapes of the elements depicted within the figures may be referred to as having those shapes (e.g., such as being circular, straight, planar, curved, rounded, chamfered, angled, or the like). Further, elements shown intersecting one another may be referred to as intersecting elements or intersecting one another, in at least one example. Further still, an element shown within another element or shown outside of another element may be referred as such, in one example.

[0066] The following claims particularly point out certain combinations and sub-combinations regarded as novel and non-obvious. These claims may refer to “an” element or “a first” element or the equivalent thereof. Such claims should be understood to include incorporation of one or more such elements, neither requiring nor excluding two or more such elements. Other combinations and sub-combinations of the disclosed features, functions, elements, and/or properties may be claimed through amendment of the present claims or through presentation of new claims in this or a related application. Such claims, whether broader, narrower, equal, or different in scope to the original claims, also are regarded as included within the subject matter of the present disclosure.