RU2499763C2 - Carne jib section shape - Google Patents

Abstract

FIELD: transport.

SUBSTANCE: carne jib with lengthwise axis false contour line extending in crosswise plane, approximately, in mirror symmetry with mirror axis s. Contour line cross mirror axis s at first and second points S₁, S₂, and, in direction of second points S₂ ahead of, at least, last third of distance D between said first and second points S₁, S₂, it converges. Contour line convergence extends to second point S₂ to terminate at rounding 1 at mirror axis s.

EFFECT: application of thinner sheet metal.

14 cl, 11 dwg

Description

The present invention relates to a crane beam for a crane, with a longitudinal axis and extending in the transverse plane, at least approximately mirror symmetrically with respect to the axis of symmetry and made at least in some sections by a straight-line imaginary contour line, the contour line intersecting the axis of symmetry in the first and the second intersection point and towards the second intersection point, at least before the last third of the distance between the first and second intersection point narrows.

Such a crane beam is shown, for example, in FIG. 13 in EP 583 552 B1.

This crane beam has the disadvantage that, in particular, when mounting in the boom system in the upper region of the crane beam, the input of forces is unfavorable. In addition, the manufacture of such a crane beam is relatively expensive.

The objective of the invention is to eliminate the described problems of the prior art.

This problem is solved using a crane beam with the characteristics of paragraph 1.

Due to the thickness of the material of its constituent parts, a real crane beam, of course, has both an external contour and an internal contour. An “imaginary contour line” refers to the outer contour of a crane beam.

Under the center of gravity of the area in the sense of this description refers to the center of gravity of the entire area (figure 2), enclosed within an imaginary contour line. That is, the concept of "center of gravity of the area" should not be interpreted solely in relation to the area concluded between the external and internal contour.

The measures proposed by the invention contribute to the fact that the crane beam can be made of one single metal sheet. The upper part of the crane beam can be used as a whole for inputting forces, in particular, between the extensions of the boom when mounted in the boom system. Due to the narrowing of the contour line upwards, a favorable ratio of shoulder length and sheet thickness is obtained. Thanks to the invention, it becomes possible to use thinner metal sheet materials than those used in the prior art.

Other preferred embodiments are defined in the dependent clauses.

The invention also relates to a boom system for a crane, at least one boom and / or one extension of the boom is made in the form of a crane beam according to one of paragraphs 1-23. Preferably, one to twenty, preferably five to ten boom extensions are provided. It is particularly preferred that more than five boom extensions are provided.

In addition, the invention relates to a crane, in particular a loading crane, with a crane beam according to one of the above embodiments or a boom system of the above kind, as well as a vehicle equipped with a crane.

Fig. 1a is a first embodiment of an imaginary contour line of a crane beam according to the invention,

1b and 1c, a contour line structure (FIG. 1b) and a corresponding metal sheet structure (FIG. 1c) of an embodiment in which the circular arc-shaped portion k _{1 is} approximated by a polygonal line,

Fig.1d boom system with three extensions of the boom, according to fig.1b,

Fig.1e crane beam shown in figa-1c, and the position of the center of gravity of the area,

Fig.1f boom system with an extension of the boom, and shows the location of the supporting elements,

Fig. 1g an arrow system with an extension of an arrow, the arc-shaped portion in the arrow and in the extension of the arrow being approximated by various polygons,

Figure 2 crane beam shown in figa-1c and 1e, and for all examples of implementation of the dash-dotted line indicates the area to which the center of gravity of the area,

Figure 3 is a second exemplary embodiment of the contour line of the crane beam of the invention,

FIG. 4 is a perspective view of the boom system shown in FIG. 1d, and

Figure 5 car with the invention of the crane.

It is assumed that all the figures are so consistent with the scale that the lengths of individual sections of the contour, as well as the angles shown, are shown in the correct ratio relative to each other. All angle dimensions are in degrees, so the full angle corresponds to 360 degrees. An acute angle is an angle smaller than ¼ of the total angle. An obtuse angle is an angle greater than ¼ and less than ½ of the total angle. An angle equal to ¼ of the total angle is called a right angle.

1 a shows a first embodiment of the shape of an imaginary contour line of a crane beam in the transverse plane of a crane beam. In this case, the transverse plane refers to the plane, which is pierced at a right angle by the longitudinal axis of the crane beam. All crane beams of the invention have a symmetry axis s located in the transverse plane, with respect to which the contour line of the crane beam in the transverse plane extends at least approximately mirror symmetrically. If the crane beam in most or all of its longitudinal length has the same cross-sectional shape, this axis of symmetry s is the direct intersection of the transverse plane with the plane of symmetry passing along the longitudinal axis (middle plane). In all embodiments, the contour line intersects the axis of symmetry s at the first and second intersection points S ₁ , S ₂ . Located on the symmetry axis s at equal distances from the first and second intersection points S ₁ , S _2, the center point M is the position of half the height of the crane beam in the transverse plane. Moving from point M in the direction _of intersection point S ₂ , we get into the area of the crane beam, which during operation experiences predominantly tensile loads. The crane beam region lying between the center point M and the first intersection point S ₁ experiences predominantly compressive loads during operation.

Depicted in figure 1, the shape of the contour line of the crane beam has four different from each other plot k ₁ , g ₁ , g ₂ , g ₃ .

Section k ₁ , located in the region of greatest compressive loads during operation, is made in the form of a circular arc, since this cross-sectional shape, as is known, has lower compression stresses and reduces the risk of buckling. It is enough if this section in this sense will have at least an approximate shape of a circular arc, which can be approximated by a polygon, as shown in fig.1b and 1c. The approximation of the circular arc shaped section k _{1 by a} polygonal line allows for easier manufacturing by bending (flanging) of metal sheets forming a crane beam. But can, of course, be implemented and the implementation option in the form of an arc of a circle using the rolling process.

The circular arc-shaped portion k ₁ can also, in this sense, have only an approximate circular-arc shape, for example, it can be formed by one or more elliptical sections with a correspondingly small eccentricity. An embodiment of a circular arc-shaped portion k ₁ formed by a sequence of short, rectilinear, elliptical and / or circular-shaped segments, respectively, is also possible.

As shown in FIG. 1, it is particularly preferred if the circular arc-shaped portion k _{1 is} made as a quarter of a circular arc, that is, extends through an angle of approximately 90 degrees. Due to this, it is possible to perform most of the shape of the contour line between the first intersection point S ₁ and the center point M in the form of a circularly shaped arc portion k ₁ . The embodiment of FIG. 1 is particularly preferred, in which the center of curvature K of the circularly shaped arc portion k ₁ lies near or on the axis of symmetry S and the center of curvature K of the region k ₁ lies between the first intersection point S ₁ and point M. Unlike image in figure 1, having the shape of an arc of a circle plot k ₁ can pass to the first intersection point S ₁ . That is, in this case, the entire contour line in the region _{of the} intersection point S ₁ and the central point M is made in the form of a circularly shaped arc portion k ₁ .

Particularly preferred, however, is the embodiment of FIG. 1, in which a third rectilinear portion g ₃ is adjacent to the circular arc-shaped portion k ₁ in the direction of the first intersection point S ₁ , which forms an angle γ with the axis of symmetry s, less than 90 degrees (here the angle γ is approximately 72 degrees). This ensures good weldability of the crane beam, the best clamping ability for welding due to sections converging obliquely to each other, as well as the ability to perform a longitudinal weld without additional edge preparation. It turns out technological performance as a whole.

This angle is preferably less than 80 degrees. Preferably, the angle γ is greater than 70 degrees.

In the embodiment shown in FIG. 1, the center of curvature K of the circular arc-shaped portion k ₁ is located directly on the axis of symmetry s between the center point M and the first intersection point S ₁ . In contrast to the one shown, the center of curvature K can also be located with some offset relative to the axis of symmetry s. However, preferably it should always be in the region between the center point M and the first intersection point S ₁ .

To the circular arc-shaped portion k ₁ in the direction of the second intersection point S ₂ tangentially to the auxiliary circle shown in FIGS. 1a and 1b, the first rectilinear portion g ₁ , which in most of the contour shape passes between the center point M and the second point S ₂ intersections. Due to this elongated straightforward execution in the upper region of the crane beam and the resulting narrowing of the cross section, a zone is formed that is better than in the prior art, adapted to the perception of tensile forces arising here, as well as support reaction forces when installed in the boom system. The imaginary continuation g ₁ 'of the rectilinear portion g ₁ (see fig. 1b) forms an acute angle ß with the axis of symmetry s, which is approximately 18 degrees in the shown embodiment. In general, the acute angle β may also lie in the range of greater than 10 degrees, preferably greater than 15 degrees. In this case, an upper limit of 25 degrees is accordingly preferable, which makes it possible to exclude a too shallow form of a straight portion g ₁ .

In the embodiment shown in FIG. 1, a second rectilinear portion g ₂ , which extends to the symmetry axis s, immediately adjoins the first rectilinear portion g ₁ , ends there with an edge 7, and intersects it at the second intersection point S ₂ . As this, in particular, can be seen in FIG. 1c, for technological reasons, it may be desirable for the second straight section g ₂ (in contrast to that shown in FIG. 1a) to be connected to the first section g ₁ not directly, but through another preferably curved plot.

In the embodiment of FIG. 1, the second rectilinear portion g ₂ forms an angle α less than 90 degrees with the axis of symmetry s (in the embodiment of FIG. 1, the angle α is approximately 65 degrees). For angle α, a range of less than 70 degrees is particularly preferred. However, in this embodiment, the angle α should be greater than 60 degrees.

The second rectilinear section g _2, which ends in a rounding in the form of an edge 7, gives the advantage that thanks to it, in the region around the top of the crane beam, a favorable local input of forces becomes possible, which is carried out, for example, by supporting sets of slip packages between individual boom extensions. It is thanks to the short arm length that a favorable relationship is obtained between the sheet thickness and the arm length, so that the deformation of the crane beam in the upper region is prevented.

However, in principle, an embodiment of the shape of the contour in this area in the form of a second circular arc-shaped section k ₂ could also be possible (see figure 3). But it is only a special variant of the more general idea proposed by the invention, namely, one in which the line of the doghouse ends in a rounding on the line of symmetry s. Alternative to the illustrated embodiment of the rounding in the form of a circular arc-shaped portion k ₂ , the rounding could also be performed, for example, in the form of an edge 7, as shown in FIG.

In general, with respect to all embodiments of the crane according to the invention, it should be said that the center of gravity F of the area by a limited contour line in the transverse plane of the area lies in the region between the center point M and the first intersection point S ₁ , i.e., below half the height of the crane beam. Due to this, the concentration of the cross section of the crane beam occurs with the greatest displacement down into the compression zone, as a result of which a section with a smaller fraction of the compression stress is formed.

As can be seen from the figures, the contour line of all embodiments has between the first intersection point S ₁ and the second intersection point S ₂ an extremum point E, with a maximum distance e from the axis of symmetry s. The distance D between the first intersection point and the second intersection point S ₁ , S ₂ may be at least twice as large as the distance e. Preferred is at least two and a half times greater distance D, particularly preferably if it is 2.75 times greater than the removal of e. The distance D may accordingly be less than three times the distance e.

It can be provided that the distance d from the contour line to the axis of symmetry s is about a quarter of the distance D between the first and second intersection points S ₁ , S ₂ , based on the second intersection point S ₂ , less than or equal to 0.8 times the maximum distance e .

In the embodiment shown in FIG. 1, the extremum point E is between the center point M and the first intersection point S ₁ at approximately the height of the center of curvature K. In the form depicted in FIG. 1a, the contour line has only one single extremum point E, that is, both in the direction of the first intersection point S ₁ and in the direction of the second intersection point S _2, the width of the crane beam, starting from the extremum point E, decreases. When approximating the plot k _{1 with a} polygonal line, as shown in Fig. 1, all points of the polygonal plot, which approximates the circular arc shaped plot k ₁ in the region of the extremum point E, are, of course, at this maximum distance e.

Starting from the auxiliary circle of radius r shown in FIG. 1a, in the embodiment shown in FIG. 1, the profile width b is ~ 2r, the profile height D is ~ 3r, and the profile width b ₁ is ~ r. These particularly preferred sizes may be provided generally for the crane beams of the invention.

Fig. 1e shows, for the embodiment of Fig. 1, the position of the center of gravity F of the area between the center point M and the first intersection point S ₁ on the axis of symmetry s. In this case, the center of gravity F of the area refers to the area shown in FIG. 2 by the dash-dot line, i.e. to the entire area that is enclosed inside an imaginary contour line (corresponds to the outer contour).

Fig. 1f shows an arrow system 5 with an extension of the arrow, further illustrating the support of the arrow system 5 through the support member 1, as well as the support of the extension of the arrow in the arrow through the support elements 2. The illustrated embodiment, of course, is, of course, only an example. The same support elements can be used in boom systems 5 with any number of boom extensions.

In the embodiment shown in FIG. 1g, two crane beams are shown, which are, for example, an extension of the boom located in the boom. It is important that the k ₁ shaped arc of a circle is approximated by various polygons. The internal cross-sectional profile in the region of the circular arc shaped portion k ₁ has fewer edges (bends), which may be a particular technological advantage in small profiles.

The manufacture of a crane beam according to the invention can be carried out, for example, by forming a crane beam from two shells, the shape of which has mutual mirror symmetry, and each of these shells corresponds to one embodiment. Both shells in the region of the first intersection point S ₁ and the second intersection point S ₂ can be connected to each other, for example, welded.

However, in a particularly preferred case, it would be possible to provide for the production of a crane beam, at least along one section of its longitudinal length, from one single metal sheet, which is accordingly deformed and then closed (for example, welded) along one single line. This line may extend, for example, in the region of the first intersection point S ₁ or the second intersection point S ₂ .

The deformation of the sheets can be carried out in a known manner or by bending and / or rolling, as well as, for example, welding.

If the wall thickness should be different, the external contour should preferably remain the same, and the sheet thickness increase inward.

4 shows an example boom system 5 with an extension of the boom located in the boom.

Figure 5 shows an example of a vehicle 3 on which the crane 4 of the invention is located. The crane 4 includes the boom system 5 of the invention, the individual boom extensions can be telescopically moved relative to each other by means of a movement cylinder 6. The possibility of telescopic movement can, of course, be provided by other drive means. In the rear region of the vehicle 3, for example, an unimaged cargo body may be located.

Claims (14)

1. A crane beam for a crane (4) with a longitudinal axis and extending in the transverse plane is at least approximately mirror symmetric with respect to the axis of symmetry (s) and made at least in some sections by a straight-line imaginary contour line, the contour line intersecting the axis of symmetry (s) at the first and second intersection points (S1, S2) and towards the second intersection point (S2), at least before the last third distance between the first and second intersection points (S1, S2), narrows the lines continues to the second intersection point (S ₂ ) and ends in a rounding on the line of symmetry (s), the contour line between the first intersection point (S ₁ ) and located at equal distances from the first and second intersection points (S ₁ , S ₂ ) the center point (M) at least partially has a section (k ₁ ), at least approximately in the form of a circular arc, and the center of curvature (K) of the circularly shaped section (k ₁ ) is on the axis of symmetry (s) or near it lies between the first intersection point (S ₁ ) and the central point (M 1), and the contour line has a straight section (g ₁ ), the imaginary continuation (g ₁ ') of which in the direction of the second intersection point (S ₂ ) intersects the axis of symmetry (s) at an acute angle (β), characterized in that the second straight section (g1) is adjacent to the second straight section (g2), which ends in a rounding. 2. A crane beam according to claim 1, characterized in that the rounding is made in the form of an edge (7). 3. The crane beam according to claim 1, characterized in that the second rectilinear section is either directly adjacent to the first rectilinear section or connected to it through a curved other section. 4. The crane beam according to claim 1, characterized in that the acute angle (β) is greater than 10 °, preferably greater than 15 ° and preferably less than 25 °. 5. The crane beam according to claim 1, characterized in that the rectilinear section (g ₁ ) is made in the form of a tangent extension of an arc-shaped circumference of the section (k ₁ ). 6. The crane beam according to claim 1, characterized in that having a circular arc-shaped portion (k ₁ ) is approximated by a polygon. 7. The crane beam according to claim 1, characterized in that the crane beam consists of at least one metal sheet, and the sheet thickness of all sections (k ₁ , k ₂ , g ₁ , g ₂ , g ₃ ) of the crane beam in the transverse plane is at least substantially the same. 8. The crane beam according to claim 1, characterized in that the crane beam consists of two shells, which are made mirror symmetrically and - preferably in the region of the first intersection point (S ₁ ) and the second intersection point (S ₂ ) - are connected to each other. 9. The crane beam according to claim 1, characterized in that the crane beam consists, at least along one section of its longitudinal extent, of one single metal sheet, which is closed along one single line, which preferably extends in the region of the first point (S ₁ ) intersection or second point (S ₂ ) intersection. 10. The boom system for the crane, characterized in that at least one boom and / or one extension of the boom is made in the form of a crane beam according to claim 1. 11. The boom system of claim 10, characterized in that the shapes of the contour of the boom and the contour lines of all the extensions of the boom - if necessary, to the degree of approximation of the arcs of the circle by polygons - are the same. 12. A crane characterized by a crane beam according to claim 1 or a boom system (5) according to claim 10. 13. The crane according to item 12, characterized in that it is made in the form of a loading crane. 14. The car (3) with a crane (4) according to item 12.

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