Polygonal booms, telescopic booms and aerial work platforms

Abstract

The present invention relates to the field of engineering machinery, and in particular to a polygonal boom, a telescopic boom and an aerial work platform, wherein the polygonal boom comprises an upper cover (10) located at the top of the polygonal boom, a bottom plate (20) located at the bottom of the polygonal boom, and a side portion (30) located between the upper cover (10) and the bottom plate (20), wherein the thickness of the side portion (30) is less than the thickness of the upper cover (10) and the bottom plate (20). By providing a side portion with a smaller thickness, the height of the polygonal boom can be relatively increased, and the moment of inertia of the cross section of the polygonal boom can be increased, thereby significantly increasing the rigidity of the polygonal boom.

Description

Technical Field

[0001] The invention relates to engineering machinery, in particular to a polygonal boom, a telescopic arm and an aerial work platform. Background Art

[0002] Aerial work equipment needs to ensure the safety and stability of personnel's aerial work. For example, for aerial work platforms, the rigidity requirements for telescopic arms are relatively high. Especially for high-meter aerial work platforms (generally above 42 meters), the height requirements for the boom of the telescopic arm are higher. If booms with the same rigidity are used, the shaking amount of high-meter aerial work platforms is much greater than that of low-meter aerial work platforms, and the operator experience is very poor. At present, the telescopic arm adopts a rectangular boom. In order to increase the rigidity of the boom, it is usually necessary to increase the height, width, and plate thickness of the boom, which will increase the weight of the boom, which in turn affects the stability of the entire aerial work equipment and increases the manufacturing cost. Summary of the invention

[0003] The purpose of the present invention is to overcome the problem in the prior art that the high-rigidity boom is heavy and affects stability, and to provide a polygonal boom that can take into account both rigidity improvement and stability maintenance.

[0004] In order to achieve the above-mentioned purpose, on one hand, the present invention provides a polygonal arm support, wherein the polygonal arm support includes an upper cover portion located at the top of the polygonal arm support, a bottom plate portion located at the bottom of the polygonal arm support, and a side portion located between the upper cover portion and the bottom plate portion, the upper cover portion includes a first flat plate portion and a first bent portion bent downward from both sides of the first flat plate portion, the bottom plate portion includes a second flat plate portion and a second bent portion bent upward obliquely from both sides of the second flat plate portion, the side portion extends vertically from the first bent portion to the second bent portion, and the thickness of the side portion is less than the thickness of the upper cover portion and the bottom plate portion.

[0005] Optionally, the side portion, the upper cover portion and the bottom plate portion are all plates of equal thickness.

[0006] Optionally, the polygonal arm includes a first slider disposed on an inner side of the first bending portion and a second slider disposed on an inner side of the second bending portion.

[0007] Optionally, the second bent portion includes a vertical edge arranged vertically and an inclined edge connecting the vertical edge and the second flat plate portion.

[0008] Optionally, an angle A between the inclined edge and the second flat plate portion is 135-165°; and / or a ratio L2 / L3 of a length L2 of the second flat plate portion to a length L3 of the inclined edge is 1-3.

[0009] Optionally, the polygonal arm includes a cover plate, a bottom plate and a web, the cover plate forms the upper cover portion, the bottom plate forms the bottom plate portion, the web forms the side portion, and two ends of the web are respectively welded to the cover plate and the bottom plate.

[0010] Optionally, the cover plate is a plate of equal thickness, and the bottom plate is a plate of equal thickness.

[0011] Optionally, the polygonal arm includes a cover plate and a bottom plate, the cover plate forming the upper cover portion and a first side portion connected to the upper cover portion, the bottom plate forming the bottom plate portion and a second side portion connected to the bottom plate portion, and the first side portion and the second side portion are welded to each other to form the side portion.

[0012] Optionally, the first side portion and the second side portion are welded at a neutral layer of the polygonal arm.

[0013] Optionally, a bending plate for increasing rigidity is provided on the outer surface of the side portion, and the bending plate and the outer surface of the side portion form a closed frame.

[0014] The present application also provides a telescopic arm, wherein the telescopic arm comprises the polygonal arm frame of the present application.

[0015] The present application also provides an aerial work platform, wherein the aerial work platform includes the telescopic arm of the present application.

[0016] Optionally, the aerial work platform is a high-meter aerial work platform.

[0017] Through the above technical solution, by providing a side portion with a smaller thickness, the height of the polygonal boom can be relatively increased, and the moment of inertia of the polygonal boom can be increased, thereby significantly increasing the rigidity of the polygonal boom. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 is a cross-sectional schematic diagram of an embodiment of a polygonal boom according to the present application;

[0019] Figure 2 yes Figure 1 A schematic cross-sectional view of the middle side portion and the bottom plate portion;

[0020] Figure 3 is a cross-sectional schematic diagram of another embodiment of the polygonal boom according to the present application;

[0021] Figure 4 It is a cross-sectional schematic diagram of another embodiment of the polygonal boom according to the present application.

[0022] Description of Reference Numerals

[0023] 10-upper cover, 11-first flat plate portion, 12-first bent portion, 20-bottom plate portion, 21-second flat plate portion, 22-second bent portion, 221-vertical edge, 222-inclined edge, 30-side portion, 31-first side portion, 32-second side portion, 40-first slider, 50-second slider, 60-cover plate, 70-bottom plate, 80-web plate, 90-bent plate, S-third slider. DETAILED DESCRIPTION

[0024] The specific implementation of the present invention is described in detail below in conjunction with the accompanying drawings. It should be understood that the specific implementation described here is only used to illustrate and explain the present invention, and is not used to limit the present invention.

[0025] In this application, unless otherwise specified, directional words such as "upper, lower, left, right" generally refer to the upper, lower, left, and right shown in the accompanying drawings; "inner and outer" refer to the inner and outer relative to the outline of each component itself. The application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0026] According to one aspect of the present application, a polygonal arm support is provided, wherein the polygonal arm support includes an upper cover portion 10 located at the top of the polygonal arm support, a bottom plate portion 20 located at the bottom of the polygonal arm support, and a side portion 30 located between the upper cover portion 10 and the bottom plate portion 20, the upper cover portion 10 includes a first flat plate portion 11 and a first bent portion 12 bent downward from both sides of the first flat plate portion 11, the bottom plate portion 20 includes a second flat plate portion 21 and a second bent portion 22 bent upward obliquely from both sides of the second flat plate portion 21, the side portion 30 extends vertically from the first bent portion 12 to the second bent portion 22, and the thickness of the side portion 30 is less than the thickness of the upper cover portion 10 and the bottom plate portion 20.

[0027] The polygonal boom of the present application can relatively increase the height of the polygonal boom and increase the moment of inertia of the cross section of the polygonal boom without increasing the weight (i.e., under the condition of the same cross-sectional area of ​​the polygonal boom) by providing a side portion 30 with a smaller thickness, thereby significantly increasing the stiffness of the polygonal boom.

[0028] Specifically, when the height and width of the polygonal arm are not limited, under the same cross-sectional area of ​​the polygonal arm, the thickness of the side portion 30 is small, so that the distance between the upper cover portion 10 and the bottom plate portion 20 (i.e., the height of the side portion 30) is set to be large, thereby increasing the force arm (h in the following formula) between the upper cover portion 10 and the bottom plate portion 20. According to the vertical moment of inertia formula: l =∫h 2 ·dA, it can be seen that the vertical moment of inertia will increase significantly and the stiffness will increase.

[0029] When the height and width of the polygonal arm are limited, under the condition of the same cross-sectional area of ​​the polygonal arm, the thickness of the side portion 30 is smaller, so that the cross-sectional area of ​​the side portion is smaller, which relatively increases the cross-sectional areas of the upper cover portion 10 and the bottom plate portion 20. Due to the limited width, the increase in the cross-sectional areas of the upper cover portion 10 and the bottom plate portion 20 is achieved by increasing the thickness of the upper cover portion 10 and the bottom plate portion 20, thereby also increasing the overall stiffness of the polygonal arm.

[0030] Regardless of whether the height and width of the polygonal arm are limited, it can be seen from the above analysis that the effect of increasing rigidity can be achieved by making the thickness of the side portion 30 smaller than the thickness of the upper cover portion 10 and the bottom plate portion 20. At the same time, since the cross-sectional area of ​​the polygonal arm is not changed, the weight and production cost of the polygonal arm are not increased, and the stability of the whole machine is not affected.

[0031] In order to ensure uniform performance of the polygonal arm at the upper cover portion 10 , the bottom plate portion 20 and the side portion 30 at their respective cross sections, the side portion 30 , the upper cover portion 10 and the bottom plate portion 20 are all plates of equal thickness.

[0032] In addition, in order to assemble a plurality of polygonal arms to form a telescopic arm, a slider needs to be provided on the polygonal arm. To ensure that the slider is firmly installed, the slider is installed at a portion with a larger plate thickness. To this end, the polygonal arm includes a first slider 40 provided inside the first bent portion 12 and a second slider 50 provided inside the second bent portion 22. By providing the first slider 40 and the second slider 50 inside the first bent portion 12 and the second bent portion 22, respectively, a stable installation can be provided through the relatively thick first bent portion 12 and the second bent portion 22.

[0033] In addition, the bottom plate 20 is configured to have an inclined bending structure, thereby forming a polygonal cross-sectional structure of the polygonal arm frame to improve the buckling performance. Figure 2 As shown, the second bending portion 22 includes a vertical edge 221 and an inclined edge 222 connecting the vertical edge 221 and the second flat plate portion 21. The specific parameters of the second bending portion 22 can be set to further increase the contribution of the bottom plate portion 20 to improving the rigidity of the polygonal arm.

[0034] Specifically, the contribution of the bottom plate portion 20 to the rigidity can be changed by setting the angle A between the inclined edge 222 and the second flat plate portion 21 , the length L3 of the inclined edge 222 , and the length L2 of the second flat plate portion 21 .

[0035] Among them, as the angle A increases, the height of the bottom plate portion 20 decreases, and the height of the side portion 30 will increase. However, when the height of the bottom plate portion 20 decreases to a certain extent, in order to ensure that the cross-sectional area of ​​the polygonal arm frame remains unchanged, the thickness of the bottom plate portion 20 will increase, so that the height of the side portion 30 decreases. Therefore, as the angle A increases, the height of the side portion 30 increases first and then decreases. In addition, when the angle A increases to 180°, the cross-section of the polygonal arm frame will change from a polygon to a rectangle, and the buckling performance of a rectangular cross-section is not as good as that of a polygon, so an excessively large angle A should be avoided. To this end, the angle A between the inclined edge 222 and the second flat plate portion 21 is 135-165°. Preferably, the angle A is 150-160°.

[0036] In addition, the rigidity of the polygonal arm can also be changed by adjusting the length L3 of the inclined edge 222 and the length L2 of the second flat plate portion 21. Specifically, when the width and height of the polygonal arm are not limited, when the cross-sectional area of ​​the polygonal arm remains unchanged, as L2 / L3 increases, the height h1 of the side portion 30 increases, the height h2 of the second flat plate portion 21 decreases, and the rigidity of the polygonal arm first increases and then decreases. When the width and height of the polygonal arm are limited, when the cross-sectional area of ​​the polygonal arm remains unchanged, as L2 / L3 increases, L2 increases, and the rigidity of the polygonal arm increases.

[0037] It is understandable that the increase in the length L2 of the second flat portion 21 will cause the length L3 of the inclined edge 222 to become shorter. A third slider S needs to be installed at the inclined edge 222. To install the third slider S, the maximum length of L3 cannot be shorter than the width of the third slider S.

[0038] Therefore, taking various factors into consideration, preferably, the ratio L2 / L3 of the length L3 of the inclined edge 222 to the length L2 of the second flat plate portion 21 is 1-3, preferably 1.5-2.

[0039] The present application can be implemented in various specific forms. Figure 1 and Figure 2 In the illustrated embodiment, the polygonal arm frame includes a cover plate 60, a bottom plate 70 and a web 80, wherein the cover plate 60 forms the upper cover portion 10, the bottom plate 70 forms the bottom plate portion 20, the web 80 forms the side portion 30, and the two ends of the web 80 are respectively welded to the cover plate 60 and the bottom plate 70. The cover plate 60 and the bottom plate 70 may both be plates of equal thickness.

[0040] Optionally, in Figure 3In the embodiment shown, the polygonal arm can include a cover plate 60 and a bottom plate 70, wherein the cover plate 60 forms the upper cover portion 10 and the first side portion 31 connected to the upper cover portion 10, and the bottom plate 70 forms the bottom plate portion 20 and the second side portion 32 connected to the bottom plate portion 20, and the first side portion 31 and the second side portion 32 are welded to each other to form the side portion 30. The first side portion 31 and the second side portion 32 can be set to an extension height as required. Preferably, the first side portion 31 and the second side portion 32 are welded at a neutral layer of the polygonal arm (i.e., a layer on the cross section of the polygonal arm that is neither subjected to tension nor compression and has substantially zero stress), so as to improve the stress of the weld and increase the fatigue life of the weld.

[0041] In addition, to further improve the stiffness, such as Figure 4 As shown, a bending plate 90 for increasing rigidity may be provided on the outer surface of the side portion 30, and the bending plate 90 and the outer surface of the side portion 30 form a closed frame. The closed frame may be in the shape of a trapezoid, a rectangle, a semicircle, or the like.

[0042] By comparing the rectangular booms of the prior art with heights above 40 meters, the stiffness of the polygonal boom of the present application can be significantly improved, and the stiffness limit of the rectangular boom can be broken. For example, in the range of 50-60m, compared with the rectangular booms of the prior art, the vertical stiffness of the polygonal boom of the present application can be increased by 20-25%, the vertical sway can be reduced by 1000-1200mm, the lateral stiffness can be increased by 12-17%, and the lateral sway can be reduced by 300-450mm.

[0043] According to another aspect of the present application, a telescopic arm is provided, wherein the telescopic arm comprises the polygonal arm frame of the present application.

[0044] By providing the side portion 30 with a smaller thickness, the height of the polygonal boom can be relatively increased, and the force arm of each point on the cross section of the polygonal boom can be increased, thereby significantly increasing the rigidity of the polygonal boom. Thus, the height of the telescopic boom of the present application can also be significantly increased.

[0045] According to another aspect of the present application, there is provided an aerial work platform, wherein the aerial work platform comprises the telescopic arm of the present application. Preferably, the aerial work platform is a high-meter aerial work platform.

[0046] By using the high-rigidity telescopic arm of the present application, it is possible to meet the safety and stability requirements of aerial work platforms, and is particularly suitable for the needs of high-meter aerial work platforms.

[0047] In addition, under the condition of the same rigidity, the aerial work platform using the polygonal boom of the present application can reduce the weight by 3-5 tons compared with the aerial work platform using the existing rectangular boom.

[0048] The preferred embodiments of the present invention are described in detail above with reference to the accompanying drawings, but the present invention is not limited thereto. Within the technical concept of the present invention, the technical solution of the present invention can be subjected to a variety of simple modifications. In order to avoid unnecessary repetition, the present invention will not further describe various possible combinations. However, these simple modifications and combinations should also be regarded as the contents disclosed by the present invention and belong to the protection scope of the present invention.

Claims

1. A polygonal boom, characterized in that: The polygonal arm frame comprises an upper cover portion (10) located at the top of the polygonal arm frame, a bottom plate portion (20) located at the bottom of the polygonal arm frame, and a side portion (30) located between the upper cover portion (10) and the bottom plate portion (20), the upper cover portion (10) comprises a first flat plate portion (11) and a first bent portion (12) bent downward from both sides of the first flat plate portion (11), the first bent portion (12) comprises an arcuate portion and a vertical portion arranged vertically, the vertical portion is connected to the first flat plate portion (11) via the arcuate portion; the bottom plate portion (20) comprises a first flat plate portion (11) and a first bent portion (12) bent downward from both sides of the first flat plate portion (11), the first bent portion (12) comprises an arcuate portion and a vertical portion arranged vertically, the vertical portion is connected to the first flat plate portion (11) via the arcuate portion; The plate portion (20) comprises a second flat plate portion (21) and a second bent portion (22) bent upwardly and obliquely from both sides of the second flat plate portion (21), wherein the second bent portion (22) comprises a vertical edge (221) arranged vertically and an inclined edge (222) connecting the vertical edge (221) and the second flat plate portion (21); the side portion (30) vertically extends from the vertical portion of the first bent portion (12) to the vertical edge (221) of the second bent portion (22), and the thickness of the side portion (30) is less than the thickness of the upper cover portion (10) and the bottom plate portion (20); Wherein, the angle A between the inclined edge (222) and the second flat plate portion (21) is 135-165°; and / or the ratio L2 / L3 of the length L2 of the second flat plate portion (21) to the length L3 of the inclined edge (222) is 1-3.

2. The polygonal boom according to claim 1, characterized in that: The side portion (30), the upper cover portion (10) and the bottom plate portion (20) are all plates of equal thickness.

3. The polygonal boom according to claim 1, characterized in that: The polygonal arm frame comprises a first slider (40) arranged on the inner side of the first bending portion (12) and a second slider (50) arranged on the inner side of the second bending portion (22).

4. The polygonal boom according to any one of claims 1 to 3, characterized in that: The polygonal arm frame comprises a cover plate (60), a bottom plate (70) and a web plate (80), wherein the cover plate (60) forms the upper cover portion (10), the bottom plate (70) forms the bottom plate portion (20), the web plate (80) forms the side portion (30), and two ends of the web plate (80) are respectively welded to the cover plate (60) and the bottom plate (70).

5. The polygonal boom according to claim 4, characterized in that: The cover plate (60) is a plate of uniform thickness, and the bottom plate (70) is a plate of uniform thickness.

6. The polygonal boom according to any one of claims 1 to 3, characterized in that: The polygonal arm frame includes a cover plate (60) and a bottom plate (70), wherein the cover plate (60) forms the upper cover portion (10) and a first side portion (31) connected to the upper cover portion (10), and the bottom plate (70) forms the bottom plate portion (20) and a second side portion (32) connected to the bottom plate portion (20), and the first side portion (31) and the second side portion (32) are welded to each other to form the side portion (30).

7. The polygonal boom according to claim 6, characterized in that: The first side portion (31) and the second side portion (32) are welded at a neutral layer of the polygonal arm frame.

8. The polygonal boom according to any one of claims 1 to 3, characterized in that: A bending plate (90) for increasing rigidity is arranged on the outer surface of the side portion (30), and the bending plate (90) and the outer surface of the side portion (30) form a closed frame.

9. A telescopic arm, characterized in that: The telescopic arm comprises the polygonal arm frame as described in any one of claims 1-8.

10. An aerial work platform, characterized in that: The aerial work platform comprises the telescopic arm as claimed in claim 9.

11. The aerial work platform according to claim 10, characterized in that: The aerial work platform is a high-altitude aerial work platform in the meter range.

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