Boom element, telescopic boom, pinning system and construction vehicle

Abstract

The present invention relates to a boom element for a telescopic boom, in particular a telescopic section or a pivotal piece of a telescopic boom, wherein the boom element has a substantially box-shaped hollow structure and wherein at least one component of a pinning system is arranged in at least one of the corner edges of the box-shaped hollow structure, wherein at least one further boom element located in the boom element and/or about the boom element can be pinned to the boom element by means of the pinning system for the purpose of fixing, and wherein the component of the pinning system is and/or includes at least one pin mount and/or at least one pin guide in which the at least one pin is guided and/or movable.

Claims

1. A telescopic boom comprising: at least first and second concentrically-positioned boom elements (1-4) together defining a longitudinal axis of the telescopic boom, each said boom element (1-4) having a substantially quadrangular box-shaped hollow structure formed by four corner beams (20) respectively having four bent corner edges, each said corner edge having a cutout (104) at the respective corner thereof, four lattice bars (21), each said lattice bar (21) intercoupling two adjacent corner beams (20), a pinning system (100) for coupling concentric telescopic sections (1-4) together upon full extension, and comprising a plurality of shells (200), each said shell (200) interposed between two adjacent concentric telescopic sections (1-4) adjacent said corner beams and affixed to an inner concentric telescopic section of two adjacent concentric telescopic sections, a plurality of spacers (201), each said spacer (201) affixed to an adjacent shell (200) in the direction of the longitudinal axis of the telescopic boom, a front support point (202) affixed to an outer concentric telescopic section of two adjacent concentric telescopic sections, and with one of said plurality of shells (200) forming a rear support point, said front and rear support points (202, 200) each having an elongate hole (105) therethrough, spring-loaded (101) pins (102) arranged to couple adjacent concentric telescopic sections together, and a telescopic cylinder (10) arranged to telescopically extend the inner concentric telescopic section (1-4) and which is pivotally mounted about a laterally-extending axis normal to the longitudinal axis of the telescopic boom, with one of said spacers (201) longitudinally spaced away from the adjacent front support (202) in unextended position and abutting said adjacent front support (202) in fully extended position.

2. The telescopic boom in accordance with claim 1, comprising a spring which is a restoring spring and an actuation unit arranged to retract the spring to release the pin connection, with the actuation unit further being arranged in an interior of the first boom element and the pin being retractable to said interior or the pin being able to be pushed outwardly with respect to the first boom element.

3. The telescopic boom in accordance with claim 1, wherein the pinning system is arranged in at least three corner beams and at least one respective pin guide is provided in a first position and in at least one second position, with the first position corresponding to a retracted position and the second position corresponding to an extended position.

4. The telescopic boom in accordance with claim 1, comprising means for exact positioning of the first and second boom elements by which the first and second boom elements are indirectly or directly positioned relative to each other, with the means having an abutment by which the positioning spacer is positioned in a compulsory manner in a predefined position on reaching an end position, and having at least one centering spigot by which the front or first support point in a respective one of the first and second boom elements is in a predefined position in a compulsory manner with the positioning spacer.

5. The telescopic boom assembly in accordance with claim 1, wherein the pin is spring biased to the engagement position and movable against the biasing force of the spring to the release position, and the pin guide includes an actuation member associated with the pin for movement of the pin, the actuation member being arranged in the interior of one of the boom elements and movable inwardly with respect to the one boom element to the release position.

6. The telescopic boom assembly in accordance with claim 1, wherein the pin is spring biased to the engagement position and movable against the biasing force of the spring to the release position, and the pin guide includes an actuation member associated with the pin for movement of the pin, the pin being movable inwardly with respect to the respective boom element to the release position.

7. A mobile crane having a telescopic boom in accordance with claim 1.

8. The telescopic boom in accordance with claim 1, wherein the spring-loaded (101) pins (102) are each arranged to extend through a guide tube (110) and into a respective cutout (104) through the elongate hole (105).

9. The telescopic boom in accordance with claim 1, wherein the shells (200), spacers (201) and front support points (202) are each L-shaped.

10. The telescopic boom in accordance with claim 1, wherein each said corner beam (20) being a profiled, extruded section.

11. The telescopic boom in accordance with claim 1, wherein said lattice bars (21) are each compressed at opposite ends thereof and directly welded to adjacent corner beams (20).

12. The telescopic boom in accordance with claim 1, additionally comprising an abutment (201a) positioned opposite one longitudinally-extending side of said spacer (201) for guiding said spacer (201) into a defined end position and a centering spigot (201b) positioned to extend toward said spacer (201) from said front support point (202).

13. The telescopic boom in accordance with claim 1, wherein the first and second boom elements each have L-shaped corner beams forming the corner edges of the box-shaped structure and lattice bars connecting the corner beams, and wherein the spacer member has a lateral L-shaped cross-section.

14. The telescopic boom in accordance with claim 13, wherein an axis of the pin of the pinning system is aligned and/or arranged substantially along the angle bisector between limbs of the corner beams and further is arranged in a plane perpendicular to the longitudinal axis of the telescopic boom; and comprising a guide tube or a holding tube inserted into a respective one of the corner beams and with the pin of the pinning system guided therein.

15. The telescopic boom of claim 13 wherein the lattice bars are connected to the corner beams by welding a flat end of each corner beam to a flat cross sectional surface at the end of a respective lattice bar.

16. The telescopic boom in accordance with claim 1, wherein each said lattice bar (21) is a slit tube having slits at opposite ends through respective corner plates (21a), and said corner beams (20) each comprise connection plates (20a) at opposite ends thereof and arranged to seat in respective slits in said adjacent lattice bars (21).

17. The telescopic boom in accordance with claim 16, wherein said corner beams (20) are directly welded to said adjacent lattice bars (21).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Further details and advantages of the invention will now be explained in more detail with reference to an embodiment shown in the drawing.

(2) There are shown:

(3) FIG. 1: a schematic front view of a telescopic boom;

(4) FIG. 2: a section A-A through the telescopic boom shown in FIG. 1;

(5) FIG. 3: a schematic representation of a first embodiment of the connection of a corner beam to a lattice bar;

(6) FIG. 4: a schematic representation of a second embodiment of the connection of a corner beam to a lattice bar;

(7) FIG. 5: a schematic representation of a third embodiment of the connection of a corner beam to a lattice bar;

(8) FIG. 6: a schematic detailed representation of the embodiment of the connection of a corner beam to a lattice bar shown in FIG. 5;

(9) FIG. 7: a schematic representation of a fourth embodiment of the connection of a corner beam to a lattice bar;

(10) FIG. 8: a schematic representation of a possible embodiment of the corner beam;

(11) FIG. 9: a further schematic representation of the embodiment of the corner beam shown in FIG. 8;

(12) FIG. 10: a further schematic representation of the embodiment of the corner beam shown in FIGS. 8 and 9;

(13) FIG. 11: a schematic detailed representation of a pinning system;

(14) FIG. 12: a schematic front view of the telescopic boom;

(15) FIG. 13: a schematic side view of the telescopic boom;

(16) FIG. 14: a schematic detailed representation of the front support point of the telescopic boom;

(17) FIG. 15: a schematic sectional representation through the front support point of the telescopic boom;

(18) FIG. 16: a schematic side view of a further embodiment of the telescopic boom;

(19) FIG. 17: a schematic side view of a further embodiment of the telescopic boom;

(20) FIG. 18: a schematic detailed view of the embodiment of the telescopic boom in accordance with FIG. 17;

(21) FIG. 19: a first schematic diagram of the pushing-out process of the telescopic boom;

(22) FIG. 20: a second schematic diagram of the pushing-out process of the telescopic boom;

(23) FIG. 21: a third schematic diagram of the pushing-out process of the telescopic boom;

(24) FIG. 22: a fourth schematic diagram of the pushing-out process of the telescopic boom;

(25) FIG. 23: a schematic representation of the telescopic boom on being exposed to wind forces;

(26) FIG. 24: a schematic representation of the telescopic boom in the extended state;

(27) FIG. 25: a schematic representation of a derrick boom;

(28) FIG. 26: a schematic representation of the telescopic boom;

(29) FIG. 27: a further schematic representation of the telescopic boom;

(30) FIG. 28: a further schematic representation of the telescopic boom; and

(31) FIG. 29: a schematic representation of the centers of gravity of a lattice crane and of a telescopic lattice crane in accordance with the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

(32) FIG. 1 shows a schematic front view of a part of the telescopic boom in accordance with the invention, with here two telescopic sections 1 and 2 being shown. As can be seen from FIG. 1, shell-shaped corner beams 20 are used in each telescopic section 1, 2, 3, 4.

(33) The corner beams 20 can be edged, bent or be manufactured from tubular sections or even as an extruded section. The corner beams 20 are connected via lattice bars 21 which are arranged at a right angle to the corner beams 20, called zero bars, or/and also at a different angle to the corner beams 20, called diagonals.

(34) Each lattice bar 21 can also be manufactured from a weld construction of four metal sheets as is shown in FIG. 2. FIG. 2 shows the section A-A from FIG. 1. The resistance torque W.sub.x about the X axis x and the resistance torque W.sub.y about the Y axis y is of equal magnitude and corresponds to that of a circular tube cross-section. A tubular lattice bar 21 is thus simulated and nevertheless the flat construction shape achieved. The wall thicknesses are optimized with respect to the possible kinking.

(35) Each telescopic section 1, 2, 3 and 4 (cf. also FIG. 23) has cut-outs 104 in the shell-shaped corner beams 20 and the inner telescopic section 2, 3 and 4 can be pinned in said cut-outs. The pinning system is marked by 100 in FIG. 1. To simplify the pairing of pin 102 and recess 104, an elongate hole 105 can be laterally provided. The elongate hole is thus aligned perpendicular to the longitudinal axis of the corner beam 20 so that a rotation is permitted. It is important that the alignment in the longitudinal axis of the corner beams 20 takes place very exactly. As explained in more detail in the following in connection with FIGS. 11 and 12, the pinning system can be actuated by means of the actuation element 103.

(36) To be able to telescope the telescopic sections 1, 2, a centrally arranged telescopic cylinder 10 is arranged by means of which the telescopic section 2 shown in FIG. 1 can be telescoped out of the telescopic section 1, but can also be retracted again.

(37) Support shells 200 are provided between each surrounding and directly adjacent telescopic section. Since the support shells 200 cause or define the spacing between the telescopic sections, the welded construction of the lattice bars 21 can have a greater cross-section 22 in some regions than at other points 23, with the points 23 in particular being the connections or in the region of the connections to the corner beams 20. The flow of force from the corner beam 20 into the lattice bar 21 is hereby made ideal, that is free of notches.

(38) For cost reasons, however, as a rule, the lattice bar 21 is produced, as known, from a tube having a circular cross-section. Then, however, the available construction space between the adjacent telescopic sections is not ideally used. The tight space conditions can be seen from FIG. 1.

(39) Further embodiments are shown in FIGS. 3 to 7.

(40) FIG. 3 shows a possible embodiment of the connection of a corner beam 20 to a lattice bar 21, with the lattice bar 21 being a slit tube. The tube in this respect has a cover plate 21a. The corner beam 20 is a normal, edged metal sheet which does not have any separate connection points, in particular connections E2, E3, E4 and E5, as shown in FIGS. 8 and 9, to save offcuts. For this reason, the connection plates 20a are necessary which are welded to the corner beam 20 and are introduced into a slit of the lattice bar at the end side and are fastened there.

(41) FIG. 4 shows an embodiment which is comparable with the embodiment shown in FIG. 3, with here, however, the corner beam 20 being manufactured from a profiled extruded section. The advantage hereby results that different plate thicknesses can be realized.

(42) The solution shown in FIGS. 5 and 6 is designed such that the connection plate 20a can be dispensed with. Here, the lattice bar 21 is compressed at its end or its ends, as is shown in detail in FIG. 6. A flat cross-section hereby arises to which the corner beam 20 can be directly welded.

(43) FIG. 7 shows a corner beam 20 and a lattice bar 21, with the corner beam 20 being welded directly into the slit lattice bar 21. In this respect, a cover plate 21a is likewise used.

(44) If the corner beam 20 is manufactured from an edged plate E1, as is shown in FIGS. 8 and 9, it can already be provided with the connections E2, E3, E4 and E5 for the lattice bars 21 forming the diagonals and, optionally, the zero bars, on the cutting out of the shape. After the firing, the plate E1 is edged at the intended point E6. After the edging, the connection between the lattice bars 21 and the connections E2, E3, E4 and E5 is established by means of weld seams S.

(45) If it should become necessary that the pinning points 104 or recesses 104 (cf. e.g. FIG. 1) are strengthened, this can also already be taken into account on the firing. A reinforced pinning plate E7 can be used, as is shown in FIG. 9. The pinning plate E7 could also be a cast part.

(46) If the reinforcement is present, the support shell 200 has to be removed accordingly for the purpose of assembly or must even comprise two parts, as is shown in FIG. 10.

(47) FIG. 11 shows a schematic representation of the pinning system 100. The pinning system 100 has a pin 102 loaded by a spring 101. The pin has an actuation unit 103. A guidance and holding pipe 110 is welded in the inwardly disposed corner beam 20 which can, for example with respect to FIG. 1, be the corner beam 20 of the telescopic section 2.

(48) The guidance and holding tube 110 in this respect substantially takes over two tasks. On the one hand, it positions the support shell 200 and, on the other hand, it positions the pin 102 of the bolting system 100 very exactly. The transmitted forces are forwarded from the guidance and holding tube 110 into the corner piece of the telescopic section 2 and thus into the corner beams 20. The pin 102 is pulled at the actuation unit 103 and brought out of engagement with the corner beam 20. The telescopic cylinder 10 can now move the inwardly disposed telescopic section and bring it to engagement at another cut-out 104 in the corner beam 20. Provision is now advantageously made that, unlike the prior art, now a plurality of pinning systems 100 are provided, in particular four pinning systems per telescopic section, that is one respective pinning system 100 in each of the corner beams 20 and advantageously per pinning point. One respective pair of telescopic boom elements in this respect preferably has two pinning points, namely a first pinning point for the retracted position and a second pinning point for the extended position.

(49) The pinning systems 100 are preferably aligned in a plane which extends perpendicular to the longitudinal axis of the telescopic section as well as in the angle bisector between limbs of the corner beam 20 with respect to its pin axis alignment.

(50) FIG. 12 shows two telescopic sections in one another, e.g. telescopic sections 2 and 3. As is further shown in FIG. 13, the telescopic cylinder 10 is connected to the telescopic section 3 and pushes it out after the release of the connection points to the surrounding telescopic section 2. The spacing from the front support point 202 and the rear support point 200 hereby becomes smaller and the support clearance causes the telescopic section 3 to tilt further down. The support shells 200 serving as rear support points 200 have already been described above in more detail. The rear support point 200 is furthermore connected to a spacer 201. For stability purposes, the spacer 201 can have a steel core 203 as is shown in FIG. 14.

(51) FIG. 15 shows the connection of the support point to the corner beams in different sections. The pin 204 closed by the compression spring serves as an abutment and holds the support shell 202 in position. It further shows a cut-free spacer with a guide screw. The hydraulically openable pin 204 is necessary so that the inner telescopic section can be removed.

(52) Additional holding apparatus 205, such as guide screws 205 in accordance with FIG. 15, can be provided. For this purpose, guide screws are used which primarily hold the spacers 201 in position, but do not lead off the force arising on the alignment of the telescopic sections into the corner beams 20.

(53) The front support point 202 is connected to the surrounding telescopic section 2. The connection can take place via the stable abutment bolt 204. It takes up the forces in the pushing-out direction of the telescopic sections.

(54) As shown in FIG. 16, the lower corner beams 20 can be drawn slightly forward. The setting on and positioning of the next corner beam is thus simplified on the installation of the telescopic boom.

(55) In addition, it can be helpful and of advantage to use further apparatus for the exact positioning. As can be seen from FIG. 17, such apparatus can, for example, be an abutment 201a which brings the spacer 201 into a defined position, that is positions the spacer 201 in a compulsory manner, on the reaching of the end position. Furthermore, centering spigots 201b can be provided which lead the front support point 202 with the spacer 201 into a defined position. FIG. 18 shows a further detail view of this. The force transmission from the means for the compulsory positioning to the inner telescopic section 3 must be ensured since hereby the exact positioning of the pinning points to one another takes place.

(56) FIGS. 19 and 20 show a more detailed illustration of the pushing-out process of the telescopic section 3 from the telescopic section 2. At the start of the pushing-out process, the support shell 200 of the telescopic section 3 pushes the spacer 201 in the direction of the front support point 202. At the end of the pushing-out process, the spacer 201 is pressed toward the front support point 202.

(57) As shown again in detail in FIGS. 21 and 22, the telescopic cylinder 10 pushes the telescopic section 3 out beyond the connection point 1000. The telescopic section 3 is laterally supported at the front support points 202 and at the rear support points 200. The longitudinal axis of the telescopic section 3 will tilt toward the longitudinal axis of the telescopic section 2 via the clearance in the support points. Consequently, the pins 102 of the pinning system 100 cannot be paired with the cut-outs 104 of the telescopic sections. If the rear support point 200 abuts the front support point 202 via the spacer 201, the force F.sub.zyl increases in the telescopic cylinder 10. The latter effects a torque about the connection which was first effected between the rear support point 200 via the spacer 201 and the front support point 202 and brings the other pinning points into position. It thereby becomes possible to pair the pins 102 to the recesses 104. It must be noted that disturbance variables such as wind forces F.sub.Wind have to be overcome (cf. FIG. 23).

(58) No connection analog to a telescopic boom is established by the tight tolerances of the cut-outs 104 to the pins 102, but rather a connection analog to a lattice boom, that is a stable pressure bar is created as a boom.

(59) The boom can be set or is set steep to relieve all support points. Erection angles of greater than 80 to the horizontal are provided here. A further criterion is the torque compensation on telescoping. FIG. 23 shows the conditions here. If the telescopic lattice boom is telescoped, two substantial variables act on the boom, namely the weight of the load and/or hook block F.sub.K having the spacing a1 and the tensile force F.sub.T of the adjustment block with the plurality of shearing strands which all have to be removed from the winch with the spacing a2. The luffing angle is selected so that both resulting torques approximately compensate one another. The support points are also hereby relieved.

(60) In addition to the fast establishing of the work capability, the small transport volume to the construction site must be emphasized as a special advantage. A great benefit of the derrick boom 1001 is the better angle on the erection of the boom which can be telescoped in, see FIG. 25. The arrangement of the winches W1, W2, W3 and W4 is likewise drawn here. In FIG. 26, the erection of a telescopic boom in accordance with the invention is shown comprising a pivotal connection piece 1 and the telescopic sections 2, 3, 4. Since the boom is erected in the stated telescoped inwardly, no derrick boom is required. A guying frame 1002 is sufficient. If the telescopic boom is erected, the telescoping of the respective telescopic sections starts in a known manner. In this respect, the luffing rope arrangement is naturally synchronously paid out in order not substantially to change the luffing angle of the telescopic boom. This will be explained in more detail by way of example with reference to FIGS. 27 and 28.

(61) FIG. 27 represents the angle conditions at the extended telescopic boom. The main boom 50 is connected to the length-variable rope arrangement 605 via the stay poles 500, with the main luffing body 60 of the main boom 50 being shown at the tip of the main boom having the reference numeral 60. The length-variable rope arrangement 605 is in turn connected to the guying frame 600. The guying frame 600 is connected via the luffing rope arrangement 604 to the superstructure 603. The guying frame 600 and the main boom 50 each have an angular encoder 601, 602.

(62) The angle is predefined for an ideal function (due to the geometric conditions) and has to be monitored from a technical control aspect. For this purpose, the two angular encoders 601, 602 deliver the data to the control. On the telescoping of the main boom inwardly and outwardly, the length-variable rope arrangement 604 is correspondingly adjusted. The aim is that the angle is maintained in the range from approximately 80 to max. 90. It can be recognized from FIG. 27 that an angle of 90 cannot be reached with a steep-set main boom 50. After the telescoping, the length-variable rope arrangement 605 is no longer used.

(63) The luffing of the main boom 50 takes place via the luffing rope arrangement 604.

(64) It can furthermore be advantageous if the guying, that is the length-variable rope arrangement 605 in the upper example, does not take place at the outer end of the main boom 50, but rather at the collar of the inner telescopic section, e.g. at the collar of the telescopic section 2 as shown in FIG. 28. The upper telescopic sections are hereby subject to the bending stress usual for normal telescopic booms, while the inner telescopic sections are loaded analog to a normal lattice crane.

(65) It remains to be mentioned that the telescopic beam in accordance with the invention is not provided for operation with a luffing ram. It is always operated with a guying frame or a derrick boom and a luffing rope arrangement.

(66) Since the crane in accordance with the invention is a crane for the installation of wind power plants, it can operated in modular form for this purpose with little transport volume and transport weight. This becomes apparent when one considers that large lifting heights, but only very small radii are required for the installation of wind power plants. Relatively little ballast is thus required for the crane work. The large amount of ballast is required due to the erection of the long (lattice) boom. This is avoided here; neither a derrick boom nor the large amount of ballast thus has to be transported to the construction site. The number of the winches which are transported to the construction site could also be reduced, which further reduces the transport volume and the transport weight. If the crane is used for other purposes, a known crane construction can take place, as described in FIG. 25.

(67) A further advantage is the small space requirements on the erecting of the boom. Only little space to set up the long lattice booms is frequently available on hilltops or on the installation of wind power plants in forest regions. A boom having a length of well over 150 m can thus only be installed on the ground with difficulty, if at all.

(68) It is a very simple and robust construction with respect to conventional telescopic booms with a guying system.

(69) The center of gravity SP of a lattice crane is drawn in FIG. 29 which is a lot higher in comparison with the center of gravity SP of the telescopic boom in accordance with the invention which can be telescoped inwardly. It can clearly be seen that the telescopic boom in accordance with the invention provides improved security against tipping over with a comparable support width SB.