SUPPORT STRUCTURE

Description

Technical field

[0001] The present invention relates to a support structure for a working machine, in particular one comprising a mast. Description of the state of the art

[0002] Support structures of the type mentioned above serve to stabilize working machines equipped with a mast, particularly a boom assembly comprising several mast arms. When the mast is not in operation, the support legs of the support structure are retracted into a support leg box to save space, so that they do not protrude or only protrude minimally when the machine is moved to another location. When the working machine, for example a mobile concrete pump, is in operation, the extended support leg often has to absorb considerable forces, which are transferred via the support leg box and directed to the ground. The force is typically transferred from the support leg box to the support leg at two points: the support leg rests against the top of the support leg box in the area of ​​the opening and is supported at its rear end on the bottom of the support leg box.

[0003] Common outriggers feature a hollow body with a downward-pointing support foot at the end protruding from the outrigger housing. The hollow body is composed of vertically oriented web plates and horizontally oriented flange plates. To prevent buckling of the outrigger at the points where force is transferred from the outrigger housing, the outrigger must be particularly robust at these points. This is typically achieved by welding transverse bulkheads into the outrigger, which means the outrigger can only be used in positions where the force is transferred through these bulkheads. This reduces the number of possible outrigger positions. In most cases, the machine can only be operated with the outrigger fully, partially, or not at all extended. Installing numerous transverse bulkheads in the outrigger would adversely increase its weight.

[0004] From DE 10 2014 014 038 A1, a support structure of the generic type is known in which the web plates of the support legs are exposed and form lower and upper bearing surfaces, and the support legs rest with the downwardly facing narrow sides of the web plates on two support strips extending longitudinally at a distance from each other in the support leg box.

[0005] From DE 20 2004 011 443 U1 and DE 10 2004 035 416 A1, which disclose the preamble of claim 1, a support device for support frames with cantilevered loads is known, in which upper load introduction blocks are provided on an inner side of the support leg box in the area of ​​its opening, and lower load introduction blocks are fixedly arranged at a distance therefrom inside the support leg box. The load introduction blocks are screwed or bolted on. Summary of the invention

[0006] Based on this, a support structure with the features of claim 1 is proposed according to the invention.

[0007] The invention is based on the insight of providing a single load application point inside the support leg box, combined with a reinforcement extending essentially over the entire length of the support leg or the extension leg for support on the single load application point.

[0008] According to the invention, a structurally simple and cost-effective load introduction with optimized force flow is provided. The combination of a single load introduction point in the support leg box (in addition to the upper chord load introduction provided at one open end of the support leg box) and continuous reinforcement in the extendable support leg enables bracing with a large number of leg positions (i.e., different extension lengths), up to full flexibility. This allows for more flexible use of the machine equipped with the support structure according to the invention.

[0009] The invention thus relates to a support structure for a working machine having a mast, with a support leg box open to a front side and with a support leg which is slidably mounted in the support leg box for movement between a fully retracted position and a position fully extended by a maximum extension length in the longitudinal direction, wherein the support leg box has a first load application device for receiving a force to be directed upwards in the support leg box during operation and a single second load application device for receiving a force to be directed downwards in the support leg box during operation, and wherein the support leg has a reinforcing element extending substantially over a length of the support leg which is designed to rest on the single second load application device.

[0010] The support leg can be multi-part, e.g., designed as a telescopic leg.

[0011] The support structure comprises exactly one first load introduction device and exactly one second load introduction device.

[0012] A load introduction device is understood to be an arrangement of at least one load introduction element suitable for load transfer.

[0013] Further advantages and embodiments of the invention will become apparent from the dependent claims, the description and the accompanying drawing.

[0014] It is understood that the features mentioned above and those to be explained below can be used not only in the combinations specified, but also in other combinations or on their own, without leaving the scope of the present invention.

[0015] The invention is shown in the drawing in a highly schematic and not to scale embodiment and is described in detail below with reference to the drawing. Brief description of the drawing

[0016] Figure 1 The image shows, in a highly simplified form, a support structure with a support leg, a support leg box, and a bearing block for a mast mounted on the support leg box. Figure 2 The figure shows a first embodiment of a support structure according to the invention in a highly schematic lateral sectional view. Figure 3 A second embodiment of a support structure according to the invention is shown in a highly schematic lateral sectional view. Figure 4 shows to the representation of Figure 2 a variant of the first embodiment with a support leg designed as a telescopic leg. Figure 5Analogous to the illustration in Figure 32, this shows a variant of the second embodiment with a support leg designed as a telescopic leg. Figure 6 Figure 1 shows a support leg box according to the first embodiment in a perspective cutaway view. Figure 7 The figure shows a further telescopic leg variant of the first embodiment in its extended state, in a side-cut perspective view. Figure 8 shows the supporting structure of the Figure 7 in a retracted state. Figure 9 shows the supporting structure of the Figure 7 in cross-section. Figure 10 shows the supporting structure of the Figure 5 in perspective view in extended state. Figure 11 shows the supporting structure of the Figure 10 in a side-cut perspective view in the extended state. Figure 12 shows the supporting structure of the Figure 10 in cross-section. Figure 13 shows a further modification of the embodiment of Figure 3 . The Figures 14a-14d show possible variations in the construction of a supporting leg hollow body. Detailed description

[0017] Identical and similar features depicted in the individual figures are designated with the same reference symbols.

[0018] Figure 1 Figure 1 shows a schematic perspective view illustrating a support structure 10 for a working machine with a mast. The support structure 10 comprises, in a manner known per se, a support leg box 12, which is integrated into a bearing block 14 for the mast. The support leg box 12 is open towards a front face 16 and is designed as a box- or cuboid-shaped hollow body.

[0019] The support leg box 12 accommodates a support leg 20, which has a hollow body 24 extending in a longitudinal direction 22 and being displaceable in the longitudinal direction 22 within the support leg box 12, as well as a downwardly projecting support foot 26 mounted at a front end of the hollow body 24. The illustration of the Figure 1 The figure shows the support leg 20 in a partially extended position.

[0020] The support leg 20 has a length L and, in a fully retracted position, is received in the support leg housing 12 with substantially its entire length L (projections through the open front 16 and possibly also through an open rear side, not shown, are possible). The support leg 20 can be moved out of the support leg housing 12 by a maximum extension length A by sliding it through the open front 16 of the support leg housing 12. In the fully extended position, a residual length D, which substantially corresponds to the entire length L minus the maximum extension length A, remains in the support leg housing 12 (see figure). Figures 2 and 3 The invention allows for any partially extended intermediate positions of the support leg.

[0021] As can be seen, for example, from the Figure 7 , 9 and 12The hollow body 24 of the support leg 20 can be composed of two spaced-apart, parallel web plates 64 and two spaced-apart, parallel chord plates 60, 62 connecting the web plates 64, namely an upper chord 60 and a lower chord 62, in particular by welding. The support leg box 12 is similarly composed of two spaced-apart, parallel web plates 54 and two spaced-apart, parallel chord plates 50, 52 connecting the web plates 54, namely an upper chord 50 and a lower chord 52, in particular by welding.

[0022] In principle, other configurations of the hollow body 24 are also conceivable, as shown in the illustration of the Figures 14-14d illustrated and described below.

[0023] According to a first embodiment of the invention, as schematically shown in the Figure 2As shown, the support leg box 12 has a first load introduction device 30 in the area of ​​its open front 16. As can also be seen, for example, from the illustration of the Figure 6 The first load introduction device 30 can be designed in a manner known per se as an essentially U-shaped reinforcing bracket, open at the bottom and having a base 40 and free legs 42 projecting downwards from the base 40. A bottom surface of the base 40 forms a support surface 44, against which the upper chord 60 of the support leg 20 is supported, as described in more detail below (see below). Figure 6When the support leg 20 bears a load during operation, its upper chord 60 rests against the support surface 44. Other configurations of the first load application device 30 are possible. For example, the U-shaped reinforcing bracket can not only be arranged in front of the upper chord 50 (as shown and described) and form the support surface 44 there, but it is also possible to place the reinforcing bracket on the upper chord so that the force is transferred through the upper chord to the base 40 of the bracket. Furthermore, as will be described below, it is possible to arrange the first load application device in the area of ​​the side surface (webs) of the support leg box.

[0024] Furthermore, according to the invention, the support leg box 12 has a single second load application device 32 inside. The second load application device 32 is arranged in the support leg box 12 at a given distance D from the front 16 of the support leg box 12. The given distance D essentially corresponds to the described residual length with which the support leg 20 remains in the support leg box 12 in its fully extended position. Typically, this "residual length" is approximately 20 to 30% of the extension length. This ensures that, when a load is applied during operation, the support leg 20 can (still) be supported with a rear end 28 on a support surface 34 of the second load application device 32. The second load introduction device 32 is designed as one or more continuous recess(s) provided for this purpose in the wall (web plates 54 and / or bottom chord 52) of the support leg box (see e.g. Figure 6 and 9The second load introduction device 32 is designed such that its support surface 34 projects towards a surface of the lower chord, as can be seen in particular from the Figure 6 , 8 and 9 This protrusion, or "raised section," serves to prevent the support leg from potentially bearing stress on points of the lower chord not designed for load distribution when moved into the retracted position (the invention deliberately omits the inclusion of further load distribution points in the support leg housing). Typically, the described raised section is approximately 20 to 50 mm, depending on the dimensions (especially the length) of the support leg. . Within the scope of his professional expertise, the specialist readily selects a suitable increase.

[0025] According to the invention, there are exactly two support points 34, 44 in or on the support leg box 12 for the load transfer of the support leg 20, namely a support point or support surface 44 for an upward load transfer at the front 16 and a support point or support surface 34 for a downward load transfer.

[0026] The position of the support point formed by the second load application device 32 is determined, as already described, at a distance in the longitudinal direction 22 from the front face 16 of the support leg box. The second load application device 32 can, for example, have a support surface 34 extending transversely (perpendicularly or at an angle other than 90° or less than 90°) to the longitudinal direction 22. Alternatively, the second load application device 32 can have several support surfaces 34 arranged at the given distance from the front face on the circumference of the support leg box on its lower chord 52 and / or its web plates 54.

[0027] In the context of the first embodiment of the invention according to Figure 2 The second load introduction device 32 can be designed similarly to the first load introduction device 30 as an essentially U-shaped bracket, open at the top and comprising a base 46 and free legs 48 projecting upwards from the base 46 (cf. e.g. Figure 6 The upper surface of the base 46 forms the support surface 34. The base 46 of the bracket can be – as shown in the Figure 6 visible - reach through the lower chord 52 of the support leg box.

[0028] As from the Figure 2 As can be seen, the support structure 10 according to the invention further comprises in the support leg 20 a reinforcing element 36 extending substantially over the length L of the support leg 20. The reinforcing element 36 is designed to rest on the support surface 34 of the single second load introduction device 32.

[0029] The reinforcement element 36 can be designed in a variety of ways. For example, the reinforcement element 36 can be formed by a reinforcement plate of the lower chord 62 extending over essentially the entire length of the support leg 20.

[0030] Alternatively, the reinforcing element 36 can be formed by two reinforcing strips extending along the respective butt edges of the web plates 64 with the bottom flange 62. In this case, it would be a multi-part reinforcing element 36, the parts of which each extend over essentially the entire length of the support leg 20.

[0031] Alternatively, the reinforcing element 36 can be formed by suitable material reinforcements or widenings of the web plates 64 in the area of ​​the connection with the bottom flange 62, as is the case, for example, in the Figure 9This is illustrated. Conversely, the reinforcing element 36 can of course also be formed by suitable material reinforcements or widenings of the base material 62 in the area of ​​the connection with the web plates 64.

[0032] The design of the reinforcement element 36 as extending essentially over the entire length of the support leg 20 gives the invention a high degree of desired flexibility, since any extension position of the support leg 20 is now possible with load transfer downwards always guaranteed via the single second load introduction device 32.

[0033] In the illustrated embodiment of the Figure 2Furthermore, the support leg 20 also has an upper chord reinforcement extending essentially over the entire length of its upper chord 60. The design of the upper chord reinforcement is governed by the above description in connection with the reinforcement element 36.

[0034] According to a second embodiment of the invention, as schematically shown in the Figure 3As shown, the second load introduction device 32 is not primarily formed in the lower chord 52 of the support leg box 12, but rather in its lateral web plates 54. For example, a reinforcing pin with a support surface 34 can be provided on or in each of the two opposing web plates 54 (each at the given distance D from the front of the support leg box 12). The reinforcing pins can, but do not have to, be arranged at the same height (in principle, the two pins can be arranged at different heights; in this case, the longitudinally extending reinforcements on the left and right of the support leg must also be arranged at different heights).

[0035] The second load introduction device 32 is designed in multiple parts in this case. The reinforcing pins of the second load introduction device 32 can each be inserted into the continuous recesses provided for this purpose in the web plate and welded in place. On the outside, the second load introduction device 32 can be essentially flush with the web plate 54, while on the inside it projects sufficiently far into the support leg box to form a suitable support surface 34.

[0036] In principle, configurations are also possible in which, due to structural constraints, the front face 16 of the support leg box is not perpendicular to the longitudinal axis of the support leg (i.e., the longitudinal direction 22). This can result in the first (upper) load application device running "obliquely" to the support leg (i.e., at an angle other than 90° to the longitudinal direction 22, in particular an angle less than 90°, e.g., between 0° and 60°).As a result, depending again on the given structural conditions, different constellations can occur for the second load application device, but these constellations fall within the scope of the present invention: i) The support surface formed by the second load application device (either from one element as in the first embodiment or from two elements as in the second embodiment) runs essentially perpendicular to the longitudinal axis of the support leg; then the distances of the support surface to the left and right on the side faces (webs) of the support leg are different. In this case, the "given distance D" is to be considered as an average value, e.g., calculated along the central axis of the support arrangement.ii) The support surface formed by the second load application device (either consisting of one element as in the first embodiment or of two elements as in the second embodiment) also extends obliquely to the longitudinal axis of the support leg, either at the same angle as the first load application device or at a different angle; in the latter case, the distances to the left and right can be either equal (same angle) or again different (different angle). In this case as well, it is convenient to consider the "given distance D" as an average value, e.g., calculated along the central axis of the support arrangement. The essential aspect of the invention is that exactly one load application device is provided inside the support leg housing, which, in its transverse extension (relative to the longitudinal axis of the leg), does not necessarily have to have the same orientation (with respect to the longitudinal direction) as the first load application device (i.e., it does not extend obliquely to it).

[0037] As can be seen from the depiction of the Figure 3 As can be seen, the reinforcing element 36, which extends essentially over the length of the support leg, is not located in the area of ​​the lower chord 62 in this embodiment, but rather at a height adapted to the position of the described reinforcing pins of the second load introduction device 32 on the web plates 64 of the support leg 20. In this case, as shown, the reinforcing element 36 can be extended upwards in height to the area of ​​the upper chord 60 and thus additionally fulfill the function of the previously described upper chord reinforcement.

[0038] Another variant is in Figure 13shown. In the support structure 10 of this variant, the first load introduction device 30 – as already indicated – is not located in the area of ​​the upper chord 50 of the support leg box, but on the webs / web plates 54. This also allows the reinforcement element 36 to be used for both upward and downward load transfer. Figures 14a, 14b and 14d Figure 36 illustrates alternative designs of the support leg hollow profile with reinforcing elements inserted or attached (into designated recesses or into a space between the two stacked U-profiles). For example, the hollow body can be constructed in two parts. Figures 14a and 14b They show a variant with two essentially U-shaped edge profiles, whose openings point towards each other, and which are joined and welded together with the legs (to form the webs or web plates). In the variants of Figures 14c and 14dA plate is welded onto an upright U-profile as a top chord.

[0039] The invention extends not only to one-piece support legs 20, as shown in the schematic representations of the Figures 2 and 3 are described, but also include multi-part extendable support legs, especially telescopic legs. Such designs are analogous to the Figures 2 and 3 in the Figures 4 or 5 shown.

[0040] The representations of Figures 4 and 5Figure 1 shows embodiments with two-part telescopic legs consisting of an extendable leg guided in a telescopic housing, the telescopic housing being slidably mounted within the support leg housing. In simplified terms, the hollow body 24 of the existing support leg, as described above, now serves as a telescopic housing 20.1 to accommodate an extendable leg 20.2 with a smaller cross-section, which is slidably mounted within it in the longitudinal direction. This necessitates the provision of load transfers in the support leg housing 12 not only for the telescopic housing 20.1 (the original single support leg), but also for the additional extendable leg 20.2.

[0041] The two in connection with the Figures 2 and 3The principles described for a second load introduction device 32 in the area of ​​the lower chord 52 or on the web plates 54 can be applied equally to the design of the load transfers between the extension leg 20.1 and the telescopic box 20.2, as described in the Figures 4 and 5 They are shown, but can also be combined with each other or with load transfer methods known from the prior art.

[0042] Thus, the exemplary embodiment of Figure 9 a variant that is located between the support leg box 12 and the telescopic box 20.1 of the first embodiment according to Figure 2The design utilizes a specific reinforcement element 36, which extends over the length L of the support leg, while for the load transfers between the extension leg 20.2 and the telescopic box 20.1, a design known from the prior art (see, for example, DE 10 2014 014 038 A1) is applied. Specifically, the material thickenings in the transition area between the web plates 64.1 and the lower chord 62.1 of the telescopic box 20.1, forming the reinforcement element 36, which extends over the length L of the support leg, simultaneously serve as inward support surfaces for downwardly extended webs 66 of the web plates 64.2 of the extension leg 20.2.

[0043] It should also be noted that the acentric arrangement of the telescopic leg in the support leg box in Figure 9 is merely exemplary and due to specific design criteria, and that of course other arrangements and in particular symmetrical arrangements are also possible.

[0044] Figure 10 shows a telescopic leg variant of the embodiment of Figure 3with a support leg box 12, a telescopic box 20.1 which is slidably mounted therein in the longitudinal direction and an extension leg 20.2 which is in turn slidably mounted in the telescopic box 20.1 in the longitudinal direction.

[0045] The support leg box 12 shows - as already mentioned in connection with the Figure 3 described - a second load introduction device 32 in the web plates 54. As described in the Figure 10 As indicated, a clamp 33 extending over the height of the web plate 54 can be provided on the outside of the web plate 54, which is supported on overhangs of the upper chord and the lower chord and serves to improve force transmission.

[0046] The telescopic box 20.1 has a reinforcing element 36.1 extending substantially along its length, formed by "rails" (so-called web plate reinforcements) applied to both sides of the web plates 64.1, which are designed to bear on the support surfaces 34 of the second load introduction device 32. The rails forming the reinforcing element 36.1 extend upwards to projections 61.1 of the upper chord 60.1, to which they are welded (see also the illustration of the Figure 12 The rails thus come into contact with the Figure 3 described dual function of increasing the force transmission both towards the first load introduction device 30 and the second load introduction device 32.

[0047] Similarly, on the web plates 64.1 of the telescopic box 20.1, opposite each other at the same height, pins forming a second load introduction device 32' with support surfaces 34' are embedded (see also Figures 11 and 12 ), and the extension leg 20.2 has a reinforcing element 36.2 extending substantially along its length, which is formed by rails applied to both sides of the web plates 64.2 and designed to rest on the support surfaces 34' of the second load introduction device 32'. The rails forming the reinforcing element 36.2 extend upwards to projections 61.2 of the upper chord 60.2, to which they are welded (see also the illustration of the Figure 12 ).

[0048] According to the invention, a single load application point is provided in the support leg box, with the result that only one load application point needs to be calculated, thus significantly reducing the computational effort for the support leg box. The single load application point in the support leg box means a force flow direction independent of the leg position (regardless of the leg position, the same two front and rear load application points are always used, unlike, for example, DE 10 2014 014 038 A1), so that there are very few parts or areas through which forces flow. The fact that reinforcement is only necessary at one point has a positive effect on the cost and weight of the construction.

Claims

1. A supporting construction (10) for a work machine comprising a mast, a supporting leg box (12) which is open to a front side (16), and a supporting leg (20) which is arranged in the supporting leg box (12) so as to be slidingly movable in longitudinal direction (22) for movement between a fully retracted position and a position in which it is fully extended by a maximum extension length (A), wherein the supporting leg box (12) comprises a first load introduction device (30) in an area of its open front side (16), and a single second load introduction device (32) having at least one supporting surface (34) arranged within the supporting leg box at a given distance (D) from the front side (16), and wherein the supporting leg (20) comprises a reinforcing element (36) extending substantially along a length (L) of the supporting leg (20) and which is designed to rest on the at least one supporting surface (34) of the single second load introduction device (32), characterized in that the single second load introduction device (32) is designed to pass through one or more through-aperture(s) provided for this purpose in a wall of the supporting leg box (12) and the supporting surface (34) of the second load introduction device (32) projects with respect to an inner surface of the supporting leg box (12).

2. The supporting construction (10) of claim 1, wherein the first load introduction device (30) in the area of the open front side (16) is designed as a reinforcement of an upper flange (50) and / or of at least one web plate (54) of the supporting leg box (12).

3. The supporting construction (10) of claim 1 or 2, wherein the single second load introduction device (32) is designed as a reinforcement of a lower flange (52) and / or of at least one web plate (54) of the supporting leg box (12).

4. The supporting construction (10) of any one of claims 1 to 3, wherein the given distance (D) corresponds substantially to the length (L) of the supporting leg (20) minus the maximum extension length (A).

5. The supporting construction (10) of any one of claims 1 to 4, wherein the reinforcing element (36) is further designed to act on the first load introduction device (30).

6. The supporting construction (10) of any one of claims 1 to 5, wherein the single second load introduction device (32) is of multi-part design.

7. The supporting construction (10) of any one of claims 1 to 6, wherein the single second load introduction device (32) comprises a supporting surface (34) which extends transversely to the longitudinal direction (22).

8. The supporting construction (10) of any one of claims 1 to 7, wherein the single second load introduction device (32) comprises a plurality of supporting surfaces (34) arranged in a manner distributed over a periphery of the supporting leg box (12), at the given distance (D) from the front side (16).

9. The supporting construction (10) of claim 7 or 8, wherein the one or more supporting surfaces (34) are formed on a lower flange (52) and / or on web plates (54).

10. The supporting construction (10) of any one of claims 1 to 9, wherein the supporting surface (34) extends at an angle of 90° to the longitudinal direction (22), or in which the supporting surface (34) extends at an angle not equal to 90° to the longitudinal direction (22).

11. The supporting construction (10) of any one of claims 1 to 10, wherein a transverse extension of the single second load introduction device (32) extends parallel to the front side (16) of the first load introduction device (30) or in which a transverse extension of the single second load introduction device (32) does not have the same orientation as the front side (16) of the first load introduction device (30).

12. The supporting construction (10) of any one of claims 1 to 11, wherein the given distance (D) in the longitudinal direction (22) is determined along a central axis of the supporting leg box (12) from the front side (16) of the first load introduction device (30) to an intersection of the central axis with the transverse extension of the single second load introduction device (32).

13. The supporting construction (10) of any one of claims 1 to 12, wherein the single second load introduction device (32) is designed as a substantially U-shaped bracket which is open at the top.