EP1266861B1 - Telescopic crane with a superlift device - Google Patents

Abstract

The cantilevered arm has a base-case (4) with several telescopic lengths (5-8) and with bracing (11) in the form of a superlift arrangement. The bracing leads over the peak of a bracing block (14) erected on the back of the base-case and consisting of two parts. A lower bracing (12) of fixed length extends as far as the bottom end of the base case. A top flexible bracing (13) of variable length leads from a fixture point in the top of the cantilevered arm to the peak of the bracing block. The bracing is held taut by a tensioning arrangement consisting of an accumulator for the flexible top bracing and a separate attachment (16).

Description

The invention relates to a telescopic crane, in particular a vehicle crane, the one equipped with a superlift boom according to the preamble of Patent claim 1.

In mobile cranes with telescopic boom, it has long been known that through a As a Superliftinrichtung designated bracing the allowable load for the Boom can be significantly increased. The Superliftinrichtung relieves the Boom by deliberate application of forces, the normal load are opposite.

A generic telescopic crane, which is designed as a vehicle crane, is For example, from DE 198 02187 A1 known. This vehicle crane has a Boom with a basic box and several austeleskopierbaren from it Telescopic shots on. He is trained with a superlift device Provided with bracing, with the brace over the top of one on the back of the basic box erected Abspannbocks is guided. The bracing exists while two Teilabspannungen. A lower bracing, coming from the top of the Abspannbocks extends into the area of the lower end of the basic box, points while a fixed length. The lower bracing can therefore, for example, from be formed a linkage. The second partial guy (upper guy) is off a flexible (i.e., slightly bendable transversely to the pulling direction) variable traction means Length formed, for example, from a rope or a chain, and leads from a Attachment point in the upper part of the jib to the top of the jib. in the Operating condition of the boom, the bracing by a in the range of Abspannbocks arranged tensioning device to relieve the telescopic shots held under tension. This tensioning device is here as a winch formed, which is arranged in the lower part of the guy trestle. The rope of upper bracing is doing over a pulley at the top of the Leading trestles guided to winch. According to the respective extended length of the telescopic boom, the upper guy on the winch to a length adjusted, at which the bracing the desired height of the relieving tensile forces reached. In this setting, the cable drum is powered by a braking device blocked, so that the desired voltage is maintained. In the operating state of the Outrigger thus affect the tensile forces of the bracing on the winch. There the winch must absorb the full load of the guy, it assigns one heavy and voluminous design.

The winch winds the guy rope in the usual way in a variety of ways juxtaposed turns schraubenlinigförmig on. It can Also several turns layers are created one above the other. The dimensions of a Winches are usually such that their width (in the direction of the axis of rotation seen) in the order of its outer diameter. When the winch is blocked in a position in which the rope is a position in the area of the radial reached outside, so furthest away from the guy clamp turns force effects, which are clearly outside the middle axis of the Abspannbocks run and to considerable bending loads in the girder to lead. The same applies to the case that the rope in the blocking position a Location near one of the two the rope layers on the rope drum laterally limiting flanges of the cable drum occupies. That requires one correspondingly massive and heavy design of the guy trestle.

Usually, the guy of a superlift device is designed so that it Transport with the winch to the base box of the telescopic boom is foldable. In many cases it happens that the length of the telescopic shots of the telescopic boom for the particular application is insufficient. Therefore, be often boom extensions in the form of a jib in lattice construction (Lattice tip) used. Such a lattice tip is at the head of the inner Stan Telescope shot attached. Between the grating tip and the telescopic boom can thereby be used pivot joints, which make it possible to Lattice tip in the retracted state of the telescopic boom on the outside of the Base box of the boom to fold. This is because of the winch occupied space without dismantling the guy Superlift device often not possible.

Object of the present invention is to provide a telescopic crane with the features of the preamble of claim 1 to the effect that the on The Abspannbcck the superlift device acting forces as low as possible Bending and torsional stresses cause and the space required for the Abspannbock is as small as possible in the state angekiappten to the base box, so that in particular a hinged to the base box jib still enough space.

This object is achieved according to the invention by the characterizing part of Patent claim 1 specified features. By the features of the subclaims This telescopic crane is advantageously further ausgestaltbar.

An essential feature of the present invention is that the Clamping the Superliftinrichtung a memory device for the flexible Pulling means of the upper bracing and one of them functionally and physically separated having trained holding device for the traction means. The holding device is such actuatable that the storage device in the operating state not with the tensile forces the guy is applied.

As a result, the storage device is no longer at high loads must be designed by the tensile forces of the bracing and therefore accordingly can be designed to be light and space-saving.

Advantageously, the holding device attached to the top of the guy clamp be useful at the same place, in which also the lower bracing with the guy is connected. This allows an exact introduction of force, which avoids the development of bending loads in the guy trestle. Of the Abspannbock is acted upon only by compressive forces. This requires the Bending trestle not so robust and voluminous and thus heavy built too will be like before.

The traction means of the upper bracing is expediently designed as a rope. In principle, it would also be possible to use a chain for bracing. Significant advantages arise when the rope of the bracing of several parallel strands, which is a band-shaped, so in the Cross section forming a flat unit.

In this context, it makes sense, the storage device as particular to form a motor-drivable cable drum, preferably at the end-trestle is arranged. If necessary, the cable drum could be moved to another location For example, be attached directly to the base box of the boom. Preferably, the cable drum is a very narrow body, so with a very short axial length (width B) formed. For example, it has one Outer diameter, at least five times, in particular at least ten times is as large as the width B. So it can externally an almost disc-like shape receive. This is especially possible if the rope of the upper bracing not helical, but only spirally on the rope drum is wound up. The individual turns are thus exclusively on top of each other and not next to each other, as is the case with a conventional winch would. If the guy rope consists of several parallel strands, these are Strands of course next to each other. For a three-strand rope version but are always only three strands in each wrap next to each other. To this Way an extremely narrow design of the cable drum is made possible. There they due to the physically separate holding function no major stresses must be exposed, not only the drum structure, but also the Drive comparatively lightweight and space-saving to run. to Namely generation of the required biasing force in the superlift device readily possible, the required length of the upper bracing first set by means of the holding device when the telescopic boom is not yet on the ultimately extended extension length is extended, and only then on the boom extend the desired length. This will cause the bias through the Drive system applied for the extension of the telescopic shots.

Instead of a cable drum, other storage devices can be used, for example, those with - similar to the pulley principle - looped arranged traction means, wherein the length of the loops is adjustable as needed.

In principle, it is possible to design the holding device such that a positive connection between the traction means and the holding device consists.

This is possible in particular when using a chain as traction means. At a Pulling rope could be provided on the rope at discrete intervals formations, which would allow such a positive connection. The latter is less convenient.

Preferably, the holding device is a force-locking connection with the Traction designed the Superliftinrichtung. It is particularly recommended that Holding device designed as a clamping device. This can, for example, with Work clamp bodies that are designed as eccentric.

Preferably, the clamping device is provided with a housing which on the Inside oblique sliding surfaces and several corresponding wedges having, under the action of the tensile forces of the traction means to be held with respect this traction means can be brought into a clamping position. It is advantageous, a separate device for releasing the clamping wedges from the clamping position provided. This device for releasing, for example, electromotive, be electromagnetically, hydraulically or pneumatically actuated.

With particular advantage, the invention is applied to a telescopic crane, whose boom consists of two separate Abspannträgem Abspannbock has, over the tips of two separate strands of a bracing are guided, as is known from DE 100 22 658 A1. The two Bracing beams can with their longitudinal axes an angle of 180 ° include, so aligned coaxially and each projecting laterally from the boom be aligned so that a lateral stabilization is achieved. In addition to lateral stabilization also a stabilization in the load plane (from the load rope spanned level), the two bracing can also be inclined to each other (angle less than 180 °) be employed. The angle between 0 ° is advantageous and 180 ° freely adjustable to meet the respective needs. In these Of course, the holding device of course consists of several units, so that assigned to each strand of the bracing a separate unit of the holding device is.

Fig. 1

einen erfindungsgemäßen Fahrzeugkran,

Fig. 2

die Einzelheit X aus Figur 1,

Fig. 3

eine Halteeinrichtung in schematisierter Form und

Fig. 4

einen Schnitt durch eine Seiltrommel.

The present invention will be explained in more detail with reference to the embodiment shown in FIGS. Show it:

Fig. 1

a vehicle crane according to the invention,

Fig. 2

the detail X from FIG. 1,

Fig. 3

a holding device in a schematic form and

Fig. 4

a section through a cable drum.

The telescopic crane shown in Fig. 1 is designed as a vehicle crane, with a a six-axle road chassis equipped undercarriage 1 and one a vertical axis rotatably mounted thereon uppercarriage 2 is equipped. Of the Upper carriage 2 carries a tiltable about a horizontal axis of rotation boom 3 and a counterweight consisting of a multitude of elements. The boom 3 has at its lower end a base box 4, from which the one inside the other Telescopic shots 5, 6, 7, 8 by means of a telescoping device, not shown are extendable. To change the inclination of the boom 3 is a hydraulic Rocker cylinder 27 is provided, on the one hand on the upper carriage 2 and on the other Base box 4 is articulated. A hoist rope 9 leads from a winch on the Upper carriage 2 to a raised at the upper end of the boom 3 Hook block 10 to which a load can be attached. By such a burden For example, the jib 3 is subject in particular to bending and buckling. to Increasing the carrying capacity of the boom 3 is a guy 11 of a Superlift device provided, consisting of a lower brace 12 and a upper bracing 13 and one on the back of the base box 4th approximately perpendicular to the central axis of the boom 3 erected Anspannbock 14 out is. The lower bracing 12 is on the one hand in the region of the lower end of the Base box 4 and on the other hand in the region of the top of the guy truss 14th attached. The lower attachment point of the brace 12 can of course if necessary also z. B. be moved in the range of the counterweight. Typically, the lower brace 12 has a fixed length and therefore can be designed for example as a linkage. Of course it is also possible to form the lower guy as rope or as a chain. In contrast to this the upper brace 13 has a variable length to accommodate different Extension lengths of the telescopic boom 3 can be adjusted. The upper Bracing 13 is in the upper part of the telescopic boom, preferably at the top of the attached to the innermost telescopic section 8 and is over the top of the bracing trestle 14 led. Details of this can be found in the schematic representation of Figure 2 corresponding to the detail X in Figure 1. At the top of the guy 14 is at the attachment point 17, both the lower brace 12 and a one Part of the upper bracing 13 forming holding device 16 is attached. One recognises, that the rope of the upper bracing 13 through the holding device 16 through a cable drum 15 is guided, for example, in the central region of the guy trestle 14 is arranged. This cable drum 15, which is driven by a motor, serves only as Rope store, so does not take the prevailing in the operating case in the bracing Pulling forces on. The latter is ensured by the holding device 16, on the next will be discussed in more detail below. This cable drum 15 is unlike usual cable drums, which in relation to the diameter of a significantly greater width, i.e. have axial length, extremely narrow running, as from the axial longitudinal section of such a cable drum of Figure 4 shows. The width is denoted by B there. From this sectional view also shows that the rope the upper bracing 13 is formed of three mutually parallel strands, so that this rope in principle like a band with the thickness of the rope diameter a strand and the triple width of the rope diameter behaves. Between Side walls 25a, 25b of the cable drum 15, the three strands of the rope 13th spirally wound on a cylindrical angle core 26, so that the individual Windings exclusively lie on top of each other and not like a conventional one Cable drum side by side (helically) are arranged. By the Division of the bracing 13 on three parallel strands, the rope diameter be considerably reduced compared to the design with a simple rope. This has, among other things, the advantage that when the deflection of the rope clearly smaller bending radii are possible. Overall, this leads to an extraordinary compact and space-saving design of the cable drum 15, since the drive and the Locking device of the cable drum should not be designed for heavy loads have to.

From Fig. 3 is a schematic representation of the holding device 16 in a axial longitudinal section. The holding device 16 has a housing 18, through that the upper bracing 13 is passed. According to the figure 4 is the bracing 13 of three individual strands, of which in the side view only a single strand is recognizable. The housing 18 is on its inside with oblique sliding surfaces 19a, 19b provided, the conical in their extension to the upper bracing 13 run. Corresponding to the inclined sliding surfaces 19a, 19b are above and below the bracing 13 each clamping wedges 20a, 20b provided due to the friction under the tensile load of the bracing 13, the indicated by an arrow, be pulled to the left, so that under the Tensile load the clamping wedges 20a, 20b in a corresponding manner to the left move and the contact pressure of the clamping wedges 20a, 20b on the upper Bracing 13 is increased according to the wedge effect. The holding device 16 can by means of a retaining tab 23 which is provided with a fastening eye 24, be hinged in the fixing point 17 as shown in FIG. 2. The upper brace13 is performed via a guide roller 22, the pair according to FIG. 2 may be, led to the cable drum 15. The design according to FIG. 3 ensures that the clamping force of the holding device 16 automatically increases when the tensile load in the upper brace 13 increases. In this way, without the requirement a positive connection in each case a secure locking of the upper bracing 13 guaranteed to the desired length.

As already stated above, the required preload in the upper bracing 13 can be ensured without problems, that the Holding device 16 with its clamping action shortly before reaching the desired extension length of the telescopic boom 3 is actuated and the Preload then over the telescoping device by the full extension is set to the desired extension length. As in the disarmament of the Telescopic boom 3, the clamping wedges 20a, 20b of itself in the clamped Dwell, a separate Rückzieheinrichtung is provided, the consists of the two units 21a, 21b. This retraction device 21a, 21b can For example, as a hydraulic or pneumatic cylinder / piston system or be designed as an electromagnetically actuated plunger. The latter is shown in FIG. 3 indicated schematically. The plunger of the retractor 21a, 21b, each at one of the clamping wedges 20a, 20b is articulated, stands under a spring load, at rest, the two clamping wedges 20a, 20b presses in the clamping position. to Unlocking the clamping position, the electromagnets are actuated, respectively Pull plunger back to the right so that the clamping effect is released. The Unlocking can be facilitated by the fact that the drive of the Cable drum 15 is operated in the sense of winding.

Such a cable drum 15, which in a preferred embodiment of the invention as is designed flat disc-like body is in Figure 4 as a perspective Sectional view shown. It has a winding core 26, on which the rope of the upper Abspann 13 is wound and the secure holding of the individual Winding layers of two circular side walls 25a, 25b is limited. Of the Diameter of the cable drum 15, i. the outer diameter of the side walls 25a, 25b is more than 10 times as large as the width B of the cable drum 15. In the illustrated Embodiment, the bracing 13 of three parallel cable strands. These are each exactly spiraling to a plurality of winding layers directly wound side by side on the cable drum 15. The individual ropes move so during winding not as a conventional cable drum helically around the winding core. Therefore, the ropes always keep one consistently exact alignment parallel to the side walls 25a, 25b.

LIST OF REFERENCE NUMBERS

1

undercarriage

2

superstructure

3

boom

4

basic box

5

telescoping

6

telescoping

7

telescoping

8th

telescoping

9

hoist rope

10

hook block

11

Leash Superlift

12

lower bracing

13

upper bracing

14

trestle

15

cable drum

16

holder

17

attachment point

18

casing

19a, b

sloping sliding surface

20a, b

clamping wedge

21a, b

Retractor

22

idler pulley

23

retaining tab

24

securing eye

25a, b

Side wall

26

winding core

27

luffing ram

B

width

Claims (13)

1. Telescopic crane, in particular vehicular crane, having a jib (3), which has a base box (4) with a plurality of telescopic shots (5-8) and is provided with a bracing (11) formed as a superlift device, the bracing (11) being guided over the tip of a gantry (14) erected on the back of the base box (4), and consists of two partial bracings, a lower bracing (12) with a fixed length from the tip of the gantry (14) extending into the region of the lower end of the base body (4), and an upper bracing (13), which consists of a flexible traction means, is of variable length from a fixing point in the upper part of the jib (3), and leads to the tip of the gantry (14), the bracing (11) being capable of being kept under tension in the operating state of the jib (3) by a tension device for detensioning the telescopic shots (5-8) disposed in the region of the gantry (14), characterised in that the tension device has a storage device for the flexible traction means of the upper bracing (13) and a traction means holding device (16) which is functionally and physically separate from the storage device and which may be so actuated that the storage device is not subject to the traction forces of the bracing (11) during operation.
2. Telescopic crane according to claim 1, characterised in that the holding device is fixed to the tip of the gantry (14).
3. Telescopic crane according to one of claims 1 or 2, characterised in that the traction means of the upper bracing (13) is formed as a cable.
4. Telescopic crane according to claim 3, characterised in that the cable consists of a plurality of, in particular at least three parallel strands.
5. Telescopic crane according to one of claims 1-4, characterised in that the holding device (16) forms a non-positively locking connection with the traction means.
6. Telescopic crane according to claim 5, characterised in that the holding device (16) is formed as a clamping device.
7. Telescopic crane according to claim 6, characterised in that the clamping device has a housing (18) with oblique slide faces (19a, 19b) disposed on the inside and a plurality of corresponding clamping wedges (20a, 20b), which under the effect of the traction forces of the traction means may be brought into a clamping position in respect of the traction means, and has a device (21a, 21b) for releasing the clamping wedges (20a, 20b) from the clamping position.
8. Telescopic crane according to claim 7, characterised in that the device (21a, 21b) for releasing is actuatable by an electric motor, electromagnetically, hydraulically or pneumatically.
9. Telescopic crane according to one of claims 3-8, characterised in that the storage device is a cable drum (15), in particular a motor-drivable cable drum (15).
10. Telescopic crane according to claim 9, characterised in that the cable drum (15) is disposed on the gantry (14).
11. Telescopic crane according to one of claims 9-10, characterised in that the cable drum (15) has an outer diameter which is at least five times, in particular at least ten times as large as the breadth B of the cable drum (15).
12. Telescopic crane according to one of claims 9-11, characterised in that the cable of the upper bracing (13) may be wound with its windings exclusively one on top of another on the cable drum (15).
13. Telescopic crane according to one of claims 1-12, characterised in that the bracing of the superlift device has two separate strands and the gantry (14) has two bracing girders, over which the two strands are respectively passed and which in order to stabilise the jib (3) are arranged or may be arranged obliquely to one another at an angle of up to 180° in a lateral direction relative to their longitudinal axes.

Images