MOBILE CRANE SUPPORT WITH LOCKING DEVICE

Description

[0001] The present invention relates to a mobile crane support device in which an arbitrary relative position of two support segments movable relative to each other is fixed by means of a locking device.

[0002] To ensure sufficient stability against tipping during operation, mobile cranes have an undercarriage with outriggers, typically consisting of four extendable and / or pivotable outriggers that can be moved transversely to the undercarriage's longitudinal axis. At their ends furthest from the undercarriage, each outrigger has a vertically extendable outrigger cylinder that rests on the ground via a support plate. Usually, two outriggers extending in opposite directions are positioned at the front and rear of the undercarriage. Deformations and load changes during crane operation cause longitudinal forces in the outriggers, which can lead to displacement. Unwanted longitudinal movement of the outriggers is typically prevented by mechanically locking them together. However, for design reasons, the number of possible locking positions is limited.

[0003] Modern cranes feature a load moment limiter that, in principle, allows them to be positioned at any outrigger position, thus simplifying or even enabling crane operation in confined spaces. However, for the reasons mentioned above, mechanical locking and therefore secure fixing of the outrigger position is not possible for all outrigger positions. This necessitates continuous monitoring of the current outrigger position and the prevention of certain crane functions if an outrigger deviates from its intended position to ensure safe crane operation. DE 10 2020 212 687 proposes fixing the outrigger position by means of a brake rail and a brake engagement element that engages the brake rail. DD53282A discloses a mobile crane outrigger device according to the preamble of claim 1.

[0004] The object of the present invention is to create a method, improved compared to previous solutions, for safely determining the position of support beams for crane operation.

[0005] This problem is solved by the subject matter of independent claim 1. The dependent claims and the collateral claim 10 define preferred embodiments of the present invention and a mobile crane comprising the present invention, respectively.

[0006] The mobile crane outrigger according to the invention comprises a support segment attachable to the undercarriage of the mobile crane, a second support segment movable within and relative to the first support segment and having a support foot movable in the vertical direction, and a locking device with contact sections assigned to the first and second support segments, respectively, which can be brought into contact with each other in any relative position between the first and second support segments to prevent movement of the second support segment. According to the present invention, the second support segment can rotate within and relative to the first support segment about an axis extending horizontally and transversely to the movement, thus selectively bringing the contact sections into contact with each other or separating them from each other.

[0007] The first support segment can be formed by a so-called support box, which occupies a fixed position on the crane undercarriage, either permanently or removable. Alternatively, the first support segment can also be formed by a support beam that is translationally movable or rotationally pivotable relative to the crane undercarriage or a support box. The support device according to the invention can therefore be composed of any number of support segments that are rotationally or translationally movable relative to each other and / or relative to the crane undercarriage, and whose translational movements can be prevented by a locking device according to the invention.

[0008] According to the present invention, the second support segment is not only capable of translational movement relative to the first support segment, i.e., extending and retracting. Furthermore, it can also pivot or tilt within the first support segment about a horizontal axis that runs transversely, and in particular perpendicularly, to the directions in which the second support segment extends from and retracts from the first support segment. This rotational movement, as will be explained in more detail later, is caused by actuating the support cylinder at the free end of the second support segment. The forces generated by the crane's weight, transmitted through the crane's outriggers into the ground, result in a transverse force on the support segments, causing the end sections of the support segments to bear against each other.The present invention utilizes this effect and the forces acting between the contact sections of the respective support segments to effectively prevent the second support segment from moving relative to the first. When the support cylinder is retracted, the lateral force load on the support segments is eliminated, and consequently, so are the forces acting in the contact sections between the support segments, thus allowing the second support segment to move within the first.

[0009] In the support device according to the invention, the relative position of the two support segments is thus determined depending on the vertical load on the support device by the crane weight, without requiring separate control.

[0010] According to one embodiment, the first support segment has in its end region facing the support foot, a lower support, in particular having at least one rolling element, over which the second support segment can be supported on the first support segment during the process; and / or in its end region facing the support foot, an upper support, in particular having at least one pressure element, over which the second support segment can be supported on the first support segment during rotation.

[0011] The supports on the first support segment, as described above, define the positions where the support segments contact each other in the various load states of the outrigger. Since a translational relative movement occurs between the contacting support segments in the area of ​​the support located below the second support segment, it is advantageous to provide one or more suitable roller elements or at least friction-reducing sliding elements to prevent wear in this area. The support located above the second support segment acts as a lever point when the mobile crane is supported and should provide a sufficiently large bearing surface for the second support segment to avoid excessive material stress.The position of this support, together with the length of the section of the second support segment remaining in the first support segment, has a decisive influence on the forces acting in the contact sections and consequently also on the ability provided by the corresponding contact sections to determine the position of the second support element relative to the first support element.

[0012] According to a further embodiment The second support element has an upper support, in particular at least one pressure element, in its end region facing away from the support foot, over which the second support segment can be supported on the first support segment during the process; and / or the second support segment is designed such that its center of gravity is always located beyond the lower support of the first support segment, in particular outside the first support segment.

[0013] The support described above serves to reduce friction and wear during the movement of the second support segment within the first support segment and, like the support located below the second support segment between the first and the second support segment, can have one or more rolling elements or at least friction- and thus wear-reducing sliding elements.

[0014] Furthermore, it is advantageous if the center of gravity of the second support segment is always located, i.e., in all relative positions, on the side of the support located below the second support segment that faces away from the crane undercarriage. This means that the section of the second support segment lying within the first support segment is automatically raised when the outrigger is unloaded, thus separating the respective contact sections from each other.

[0015] In another embodiment, the respective contact sections are arranged on an inner wall of the first support segment and on an outer wall of the second support segment. However, it is also conceivable that at least one of the contact sections is not arranged directly on its associated support segment, but only indirectly via one or more structures located between the contact section and the support segment, which transmit the forces occurring between the contact section and the support segment.

[0016] According to the invention, the respective contact sections interlock in a form-fitting manner, in particular wherein at least one of the contact sections has a toothing or an equivalent profile suitable for creating a form-fitting connection between the contact sections.

[0017] In a further embodiment, the locking device includes a release device which is pre-tensioned as soon as the contact sections are brought into contact with each other and which, in the pre-tensioned state, tends to separate the contact sections again, in particular wherein the release device comprises an elastic spring. Alternatively or additionally to a center of gravity of the second support segment located outside the first support segment, such a release device serves to enable movement of the second support segment when the support device is unloaded. For example, the release device can have a support element that contacts the inner wall of the first support segment and / or its contact section in order to introduce the pre-tensioning force generated by a pre-tensioning element, for example an elastic spring, into the first support segment.The contact element can be made partially or entirely from a friction-reducing material to prevent wear.

[0018] According to another embodiment, the traversing movement of the second support segment relative to the first support segment is effected by a hydraulic cylinder. In principle, any suitable drive is conceivable for this purpose, such as a mechanical drive incorporating a gearbox.

[0019] According to another embodiment, the support foot can have a hydraulic support cylinder which, for example, is in turn supported on the ground via a support plate.

[0020] In another embodiment, the first support segment is formed by a support box, with telescopic support beams on both sides of the support box, each forming a second support segment.

[0021] Another aspect of the present invention relates to a mobile crane with a support device according to one of the embodiments described above.

[0022] The present invention is explained in more detail below with reference to a preferred embodiment and the accompanying figures. The invention can comprise all of the features disclosed herein individually or in any meaningful combination.

[0023] It shows: Figure 1 shows a support device according to the invention in the unloaded state; Figure 2 shows the support device made of Figure 1 in a stressed state.

[0024] The Figure 1Figure 1 schematically illustrates the structure and function of the support device according to the invention using a single pair consisting of a first support segment or support box 1 and a second support segment or support beam 2. The support beam 2 extends within the support box 1 and can be extended horizontally T from the support box 1 to the right and retracted back into it to the left by means of a hydraulic cylinder (not shown). For supporting the mobile crane on both sides, the support box 1 also accommodates a second support beam (not shown), which can be extended from the support box 1 to the left and retracted back into it to the right in the same manner as the first support beam 2.

[0025] The support beam 2 has at its free end, which is away from the support box 1 and the crane undercarriage, a support foot 3 which is movable in the vertical direction V and which comprises a support plate and a piston rod of a hydraulic cylinder 17 which is pivotally connected to it.

[0026] In the Figure 1 In the unloaded state of the support device shown, the hydraulic cylinder (not shown) is able to move the support beam 2 relative to the support box 1 in the direction of displacement T. The support beam 2 rests on its bearing 12, which is designed as a sliding element, and on a bearing 8 of the support box 1, which has at least one rolling element 7, and slides or rolls on the bearings 12 and 8, respectively, on the inner surface of the support box 1. The position of the support beam's center of gravity S beyond the bearing 8 or outside the support box 1 causes a clockwise tilting moment, so that the contact sections 5 and 6 are kept apart.

[0027] Once the desired length of the outrigger 2 has been extended from the support box 1 (the left-hand outrigger, not shown, can be extended from the support box 1 to any other length), the support leg 3 is extended vertically downwards by means of the hydraulic cylinder 17 to support the mobile crane. The contact force generated upon contact with the ground causes the outrigger 2 to rotate or tilt relative to the support box 1 in the area of ​​the supports 8 and 10 about axis A and counterclockwise. The outrigger 2 now rests against the support box 1 via the support 10, whereby the contact surfaces 6 and 5, located on the outer surface 14 of the outrigger 2 and on the inner surface 13 of the support box 1, respectively, are brought into contact. In the example shown, the contact surfaces 2 are designed as corresponding tooth profiles and interlock positively.To enable the contact surface 6 to engage over the entire travel range of the support carrier 2, the contact surface 5 extends over the necessary length inside the support box 1. Due to the positive engagement of the contact surfaces 5 and 6, movement of the support carrier 2 in the travel direction T is no longer possible.

[0028] As soon as the support leg 3 is raised vertically again by means of the hydraulic cylinder 17 after the crane operation, the support device is relieved of pressure. Due to the position of the center of gravity S and the preload force acting on the telescopic box 1 via the sliding piece 15 by the spring 16, a clockwise rotational movement about the axis A is again caused in the area of ​​the supports 8 and 10, separating the contact sections 5 and 6 from each other again and releasing the pressure in the Figure 1The visible state has been assumed. A movement of the support beam 2 in the unloaded state of the support device is again possible.

Claims

1. Mobile crane support device with - a first support segment (1) that can be attached to the undercarriage of the mobile crane; - a second support segment (2) that can be moved inside and relative to the first support segment (1) and has a support foot (3) that can be moved in the vertical direction (V); - a locking device (4) with contact sections (5, 6) associated with the first support segment (1) and the second support segment (2) respectively, which can be brought into contact with each other to prevent a movement (T) of the second support segment (2) in any relative position between the first support segment (1) and the second support segment (2); wherein the second support segment (2) can rotate within and relative to the first support segment (1) about an axis (A) extending in the horizontal direction (H) and transversely to the movement (T), and thus selectively bring the contact sections (5, 6) into contact with one another or separate them from one another, characterised in that the respective contact sections (5, 6) engage with each other in a form-fitting manner.

2. Mobile crane support device according to claim 1, wherein the first support segment (1) - has a lower support (8) in its end region facing the support foot (3), in particular having at least one rolling element (7), via which the second support segment (2) can be supported on the first support segment (1) during movement; and / or - has an upper support (10) in its end region facing the support foot (3), comprising at least one pressure element (9), via which the second support segment (2) can be supported on the first support segment (1) during rotation.

3. Mobile crane support device according to one of claims 1 and 2, wherein the second support segment (2) - has an upper support (12) in its end region facing away from the support foot (3), in particular at least one pressure element (11), via which the second support segment (2) can be supported on the first support segment (1) during movement; and / or - is configured such that its centre of gravity (S) is always located beyond the lower support (8) of the first support segment (1), in particular outside the first support segment (1).

4. Mobile crane support device according to one of claims 1 to 3, wherein the respective contact sections (5, 6) are disposed on an inner wall (13) of the first support segment (1) and on an outer wall (14) of the second support segment (2).

5. Mobile crane support device according to one of claims 1 to 4, wherein at least one of the contact sections (5, 6) has a toothing.

6. Mobile crane support device according to one of claims 1 to 5, wherein the locking device (4) has a release device (15) which is preloaded as soon as the contact sections (5, 6) are brought into contact with each other and which, in the preloaded state, tends to separate the contact sections (5, 6) apart again, in particular wherein the release device (15) comprises an elastic spring (16).

7. Mobile crane support device according to one of claims 1 to 6, wherein the movement (T) of the second support segment (2) relative to the first support segment (1) is effected by a hydraulic cylinder or a mechanical drive.

8. Mobile crane support device according to one of claims 1 to 7, wherein the support foot (3) has a hydraulic support cylinder (17).

9. Mobile crane support device according to one of claims 1 to 8, wherein the first support segment (1) is formed by a support box with support beams that can be moved on both sides of the support box and each form a second support segment (2).

10. Mobile crane with a support device according to one of claims 1 to 9.