Abstract
An articulated boom of a large manipulator includes a plurality of boom segments connected to one another via articulated joints. At least one of the boom segments has a welded assembly forming a box profile in which an upper belt and a lower belt are connected to one another via lateral web plates. At least one of the web plates, the upper belt, and/or the lower belt is formed at least by one sheet metal section, which has at least one bending running essentially in a longitudinal direction of the boom segment. The at least one bending ends at a distance from an end of the sheet metal section so that the end of the sheet metal section is unbent.
Claims
1. Method for producing a distal boom segment of an articulated boom of a large manipulator wherein a box profile is produced by welding an upper belt and a lower belt to lateral web plates, wherein before welding the upper belt, lower belt and web plates, at least one bending running essentially in the longitudinal direction of the distal boom segment is introduced into at least one sheet metal section of the upper belt, lower belt and/or web plates, wherein the at least one bending ends at a distance from an end of the sheet metal section so that the end of the sheet metal section is unbent, wherein the at least one sheet metal section comprises a first sheet metal section and a second sheet metal section, the first sheet metal section having a first thickness, the second sheet metal section having a second thickness that is greater than the first thickness.
2. Method according to claim 1, wherein the at least one bending is introduced by a forming process.
3. Articulated boom of a large manipulator having a plurality of boom segments connected to one another via articulated joints, wherein a distal boom segment of the plurality of the boom segments comprises a welded assembly forming a box profile in which an upper belt and a lower belt are connected to one another via lateral web plates with respective welds, wherein at least one of the web plates and/or the upper belt and/or the lower belt is formed at least by one sheet metal section which has at least one bending running essentially in a longitudinal direction of the boom segment, wherein the at least one bending ends at a distance from an end of the sheet metal section so that the end of the sheet metal section is unbent, wherein at least one of the web plates and/or the upper belt and/or the lower belt comprises a first sheet metal section and a second sheet metal section, the first sheet metal section having a first thickness, the second sheet metal section having a second thickness that is greater than the first thickness, wherein the first sheet metal section and the second sheet metal section are connected to one another at a transition, wherein the first sheet metal section comprises a bending running along a longitudinal direction of the distal boom segment.
4. Articulated boom according to claim 3, wherein the at least one bending has a V-shaped profile cross-section.
5. Articulated boom according to claim 3, wherein the at least one bending has an arc-shaped profile cross-section.
6. Articulated boom according to claim 3, wherein the at least one bending is directed into an interior of the box profile or outwards out of the box profile.
7. Articulated boom according to claim 3, wherein the first sheet metal section has at least two bendings extending substantially in the longitudinal direction of the distal boom segment.
8. Articulated boom according to claim 7, wherein the at least two bendings are aligned converging along the longitudinal direction of the distal boom segment.
9. Articulated boom according to claim 7, wherein the at least two bendings are each directed in an interior of the box profile or each directed outwardly out of the box profile, or in that of the at least two bendings at least one is directed in the interior of the box profile and at least one is directed outwardly out of the box profile.
10. Articulated boom according to claim 3, wherein a profile angle (a) of the box profile is formed in the region of the at least one bending between one of the web plates and the upper belt and/or between one of the web plates and the lower belt, offset to a right angle between 2 and 15 degrees.
11. Articulated boom according to claim 3, wherein the first sheet metal section forms one of the web plates of the distal boom segment from the transition up to an end hose holder at a boom tip.
12. Articulated boom according to claim 3, wherein the first thickness is 2 millimeters.
13. Articulated boom according to claim 12, wherein the second thickness is 3-12 millimeters.
14. Articulated boom according to claim 12, wherein the second thickness is 3 millimeters.
Description
(1) In the drawing:
(2) FIG. 1 shows a large manipulator with an articulated boom according to the invention,
(3) FIG. 2 shows a segment of the articulated boom,
(4) FIG. 3 shows a part of the boom segment with a single bending,
(5) FIG. 4 shows a box profile with single bending,
(6) FIG. 5 shows a part of the boom segment with a double bending,
(7) FIG. 6 shows a box profile with double bending,
(8) FIG. 7 shows an end area of the boom segment,
(9) FIG. 8 shows a web plate with a double bending,
(10) FIG. 9 shows a web plate with double longitudinal and cross bending and
(11) FIG. 10 shows a box profile with outwardly directed bendings
(12) FIG. 1, marked with the reference sign 1, shows an articulated boom according to the invention. The articulated boom 1 is mounted on a chassis 14 of a large manipulator 2 designed as a truck-mounted concrete pump with the articulated boom 1 folded up. The articulated boom 1 has a plurality of boom segments 4, 4a connected by articulated joints 3, which can be unfolded for operation of the large manipulator 2. The boom segments 4, 4a are designed as box profiles 5 (FIGS. 4, 6, 10), manufactured as welded constructions with an upper belt 6, a lower belt 7 and two lateral web plates 8. In the design example shown here, the last boom segment, i.e. the tip boom section 4a of the articulated boom 1, is provided with a special sheet metal section 9. This sheet metal section 9, which forms the web plate 8 of boom tip section 4a, has two bendings 10 running essentially in the longitudinal direction of boom segment 4a. These bendings 10 of the web plate 8 prevent the formation of distortions during the welding process. As shown in FIG. 1, the web plate 8 of the last boom segment 4a is made of two sheet metal sections 9, 12 of different thicknesses, which are connected by a transition 13. This transition 13 is achieved by a butt welding process which joins the two sheet metal sections 9, 12 of different thicknesses to form web plate 8. To prevent distortions in the sheet metal section 9 with the smaller thickness, the bendings 10 running in the longitudinal direction of boom segment 4a are provided in this sheet metal section 9. As an alternative to the two sheet metal sections 9, 12, the web plate 8 can also be formed from a single sheet metal section with one or more bendings 10.
(13) FIG. 2 shows a detailed view of the last boom segment 4a of the articulated boom 1 according to FIG. 1, whereby the boom segment 4a is visible from below, so that the lower belt 7 is on the upper side. FIG. 2 further shows that the web plate 8 of the boom segment 4a is formed by the two differently thick sheet metal sections 9, 12, which are connected by means of the transition 13. The bendings 10 running in longitudinal direction of the tip boom segment 4a are only arranged in the sheet metal section 9 with the smaller thickness. The sheet metal section 9 with the smaller thickness forms the web plate 8 of the last boom segment 4a, from the transition 13 arranged approximately in the middle of the boom segment 4a up to the end hose holder 15 at the boom tip 16. With such a sheet metal section 9 it is already possible to save considerable weight at the last boom segment 4a. Because of the relatively small moment which has to be absorbed by tip boom segment 4a due to the end hose 17 at the end hose attachment 15, the use of thinner sheet metals is particularly well possible here, whereby a weight reduction at tip boom segment 4a allows further weight reductions at the remaining boom segments 4 (FIG. 1), since the moment exerted by tip boom segment 4a itself is reduced to the remaining articulated boom 1 (FIG. 1). While the front, thinner sheet metal section 9 of the web plate 8 preferably consists of 2 mm sheet metals, the rear, thicker sheet metal section 12 preferably consists of 3 mm thick sheet metals. As already shown in FIG. 2, the bendings 10 in the sheet metal section 9 end at a distance from the end 11 of the sheet metal section 9, so that the end 11 of the thinner sheet metal section 9 is unbent and allows a simple connection in the transition 13 with the thicker sheet metal section 12 of the web plate 8. The two bendings 10 running essentially in the longitudinal direction of the boom segment 4a are aligned along the longitudinal direction of the boom segment 4a so that the bendings 10 converge in the web plate 8 at the boom tip 16.
(14) FIG. 3 shows the front section of the boom segment 4a as shown in FIG. 3, but here with a single bending 10 in the thinner sheet metal section 9. The single bending 10 in the sheet metal section 9 forming the web plate 8 runs approximately centrally, essentially in the longitudinal direction of the boom segment 4a and ends at a distance from the ends 11 of the sheet metal section 9, so that the ends 11 are not bent, as can be seen. The simple bending 10 shown here has a V-shaped profile cross-section, as can also be seen in FIG. 4.
(15) FIG. 4 shows a sectional view through the sectional plane B-B indicated in FIG. 3 through the box profile 5 of boom segment 4a. FIG. 4 shows that the bending 10, which is located in the middle of the web plates, has a V-shaped profile cross-section. This profile cross-section is easy to produce and is effective against the formation of distortions in the sheet metal section 9 of boom segment 4a, which forms the web plate 8. The bending angle β of the V-shaped profile cross-section is between 160 and 176° between the two bending sections, whereby the bending radius of the V-shaped profile cross-section is relatively small, as can be seen. The profile angle α of the box profile 5 in the area of the at least one bending 10 is between the web plate 8 and the upper belt 6 and between the web plate 8 and the lower belt 7 in the case of the single bending 10 preferably between 3 and 10 degrees, to a right angle which starts from the unbent upper belt 6 or the unbent lower belt 7. With this arrangement of the web plates 8 and the upper belt 6 and the lower belt 7, the formation of distortions during the welding process can be effectively prevented. The shown bending 10 into the inside of the box section 5 does not significantly change the geometry or diameter of the boom segment and allows, for example, to use already constructed pipe holders leading through the boom without any design changes being necessary, since the cross-section of the boom segment 4a in the box profile 5 is only slightly reduced.
(16) FIG. 5 shows the front part of the boom segment as shown in FIG. 3 with a double bending 10 in the thinner sheet metal section 9. The double bending 10 in the sheet metal section 9 forming the web plate 8 run towards each other in the longitudinal direction of the boom segment 4a and meet at the boom tip 16 at boom segment 4a. The bendings 10 each end at a distance to the ends 11 of the sheet metal section 9, so that the ends 11 are, as can be seen, unbent. The double bending 10 shown here have a simple V-shaped profile cross-section, as can be seen in FIG. 6.
(17) FIG. 6 provides a sectional view through the sectional plane A-A indicated in FIG. 5 through the box profile 5 of boom segment 4a. FIG. 6 shows that the two bendings 10 running essentially in the longitudinal direction of boom segment 4a in the sheet metal sections 9 forming the web plate 8 are directed into the interior of the box profile 5. The two bendings 10 converge in the longitudinal direction of the boom segment 4a and converge in the area of the boom tip 16. FIG. 6 shows that the bendings 10 arranged on the web plates 8 have a V-shaped profile cross-section. This profile cross-section is easy to produce and is effective against the formation of distortions in the sheet metal section 9 of boom segment 4a, which forms the web plate 8. As can be seen, the bending radius of the V-shaped profile cross-section is relatively small. The profile angle α of the box profile 5 in the area of the bendings 10 between the web plate 8 and the upper belt 6 and between the web plate 8 and the lower belt 7 in the case of the double bending 10 of the sheet metal section 9 forming the web plate 8 is preferably between 2 and 15 degrees, to a right angle which starts from the unbent upper belt 6 or the unbent lower belt 7. This arrangement of the web plates 8 and the upper belt 6 and the lower belt 7 effectively prevents the formation of distortions during the welding process. The shown bendings 10 into the inside of the box profile 5 allow the use of already constructed tube holders without the need for constructional changes to them, because the cross-section of the boom segment 4a in the box profile 5 is only minimally reduced by the bendings 10. In addition to these bendings 10 with V-shaped profile cross section, curved profile cross sections are also conceivable, where the curve of the profile preferably has a constant radius. The bendings 10 can all be easily inserted into the sheet metal section 9 prior to welding of the boom segment 4a by forming processes such as die bending or folding or free bending or embossing or rolling or deep drawing or similar.
(18) FIG. 7 shows a view of the end section of the boom segment 4a as shown in FIG. 5 in the indicated position C. In this illustration it can be seen that the ends 11 of the sheet metal section 9 are unbent, i.e. straight continuous, so that an approximately right-angled box profile 5 is given at the end of the partial area, which offers a simple transition 13 (FIG. 2) to the rear partial area of the last boom segment 4a (FIG. 2).
(19) FIG. 8 shows a view of the web plate 8 with a double bending 10, whereby here the bendings 10 running essentially in the longitudinal direction of the boom segment 4a extend to the end 11 of the sheet metal section 9.
(20) FIG. 9, on the other hand, shows a detailed view of a web plate 8 with a double longitudinal bending 10. Here, the two bendings 10, which are essentially made in the longitudinal direction, run towards each other and end at a distance from the end 11 of the sheet metal section 9. At the end of the bendings 10, which run in the longitudinal direction, cross bendings 18 are made in the sheet metal section, which straighten the end 11 of the sheet metal section 9, so that the end 11 of the sheet metal section 9 is unfolded and enables a simple transition 13 (FIG. 2) to unfolded sheet metal sections 12. (FIG. 2)
(21) FIG. 10 shows a sectional view through the sectional plane A-A indicated in FIG. 5 through the box profile 5 of boom segment 4a, whereby the box profile 5 here has outwardly directed bendings 10. The two bendings 10 running essentially in the longitudinal direction of the boom segment 4a in the sheet metal sections 9 forming the web plate 8 are directed out of the box profile 5 of the boom segment 4a. With the alignment of the bendings 10 outwards from the box profile 5, more rigidity and a higher section modulus of the boom segment 4a is achieved, since the cross section of the boom segment 4a in the box profile 5 is increased by the outwardly directed bendings 10. The two bendings 10 converge in the longitudinal direction of the boom segment 4a and in the area of the boom tip 16. FIG. 10 shows that the bendings 10 arranged in the web plates 8 have a V-shaped profile cross-section. This profile cross-section, which is easy to produce, effectively prevents the formation of distortions in the sheet metal section 9 of boom segment 4a, which forms the web plate 8. As can be seen, the bending radius of the V-shaped profile cross-section is small.
LIST OF REFERENCE SIGNS
(22) 1 articulated boom 2 large manipulator 3 articulated joint 4 4a boom segment 5 box profile 6 upper belt 7 lower belt 8 web plate 9 sheet metal section (thin) 10 bending 11 end 12 sheet metal section (thick) 13 transition 14 chassis 15 end hose holder 16 boom tip 17 end hose 18 cross-bending
