EP3743367B1 - Tower crane - Google Patents

Description

The invention relates to a tower crane, in particular a top-slewing crane, with a boom and a counter-jib, the boom or counter-jib being articulated to the tower top and/or revolving platform by means of at least one connection point.

Jibs or counter-jibs of a tower crane, in particular a top-rotating tower crane, are usually articulated via a non-positive connection to the tower top or any rotating platform in the area of the tower top. For assembly purposes, such connections should be articulated and should be able to be made without tools if possible. The connection is usually made via several separate connection points.

Connection points are known whose connection partners are locked together by means of a bolt, for example a bolt or a sheet metal bracket with a bolt. The connection point is then articulated about a horizontal transverse axis, ie the locking axis. Since the force connection between the connection partners is provided by the bolt and the majority of the forces are thus introduced into the bolt it must therefore be comparatively large or large in size.

For medium-sized cranes, this can weigh around 18 kg.

Additional securing of the connection point, in particular of the boom or counter-jib, is carried out using steel safety ropes, which are intended to take on a catching function, particularly during the armament process.

A disadvantage of the previous design is that there is no visibility of the movement of the boom or counter-jib during dismantling before the connection is finally released, ie during the removal of the bolt. Dismantling is carried out using an auxiliary crane that picks up the jib/counter jib. If this does not grip the boom/counter-jib exactly at its center of gravity, the boom/counter-jib can swing unpredictably away from the connection point after the lock has been released. In the worst case, the component can swing back into the crane structure in an uncontrolled manner and cause significant damage to the crane. CN 201 850 084 U discloses a crane according to the preamble of claim 1.

The object of the present invention is to improve the connection of the boom and counter-jib to the crane tower.

This task is solved by a tower crane according to the features of claim 1. Advantageous configurations of the tower crane are the subject of the dependent claims.

Starting from a tower crane, in particular a tower crane, ideally a top-slewing crane, it is proposed according to the invention to improve the at least one connection point between the boom or counter-jib and the tower top in such a way that force transmission is realized via suitable stop surfaces of the connecting parts of the connection point. During crane operation, these stop surfaces are pressed against each other by an applied compressive force, so that a frictional connection between the boom/counter-jib and the tower top is provided.

To provide an articulated connection, a first connecting part is provided that has a concave stop surface. In contrast, a second complementary connecting part of the connection point has a convex counter-stop surface. The design of the stop surfaces ensures a certain relative movement of the connected crane parts to one another and thus ensures the desired articulation of the connection. Preferably, this enables a relative movement of the boom/counter-jib relative to the crane tower about a horizontal axis oriented transversely to the longitudinal axis of the boom. Ideally, the negative radius of curvature of the concave stop surface is matched to the positive radius of curvature of the convex counter-stop surface.

Unlike in the prior art, force transmission of the non-positive connection should no longer take place by means of a separate component, such as a bolt, but instead via suitable stop surfaces of the individual connecting parts. The resulting connection point can therefore be constructed much more simply and effectively.

The connection between the boom and the tower top or the counter-jib and the tower top and/or the rotating platform is preferably realized by means of several connection points. For example, corresponding connecting parts are provided on the respective end faces of the corner posts of a lattice boom. The complementary connecting parts are located in the area of the tower top and can, for example, be provided on a corresponding connecting element of the crane tower or on a rotating platform installed in the area of the tower top.

The necessary pressure force, which leads to the respective connecting parts being pressed together, is generated, for example, by the respective boom bracing of the counter-jib or jib, which pulls the jib or counter-jib in the direction of the tower top. In the same way, any load moment on the boom or counter-jib also leads to a corresponding compressive force.

According to the invention, the second connecting part is designed in the form of a connecting head, the connecting head being defined as a counter-stop surface by a defined radius. For example, the connecting head can be a head piece which protrudes from the end face of the boom or counter-jib, in particular the corner post, and which provides the corresponding radius at its end facing the tower top. In particular, the connecting head forms at least a semicircle or half cylinder, with the central axis of the cylinder extending in the horizontal direction.

The first connecting piece is accordingly equipped as a complementary connecting socket for receiving the connecting head. According to the invention, the connecting socket is designed by an adapted inner radius, which corresponds to the radius of the connecting head or is dimensioned slightly larger. The inner wall of the connecting socket forms the appropriate stop surface of the first connecting part.

Optionally, it can be provided that at least one connecting bolt is inserted or can be inserted to secure the connection point. A horizontally aligned bolt proves to be advantageous here, which is inserted or can be inserted into corresponding bolt receptacles of the first and/or second connecting part. The corresponding connecting bolt can be used to absorb tensile forces in the horizontal direction (boom direction). Since the pressure or tensile force ratio in the area of the connection point is significantly at the expense of the pressure forces carried by the stop surfaces, the connecting bolt can be dimensioned comparatively small. Ideally, there is a force ratio between compressive and tensile forces of around 10:1.

It is particularly advantageous if the bolt receptacle or the connecting bolt is located in the center of the convex counter-stop surface, ie in the center of the radius formed of the connecting head, which has advantages with regard to the pivoting movement of the jib or counter-jib.

Another advantage of the connection point is the possibility of creating and/or releasing the connection without tools. The boom part/counter-jib part to be assembled/dismantled is usually picked up by means of an auxiliary crane and brought into or removed from the connection area.

During the assembly process, the crane operator of the auxiliary crane must bring the stop surfaces of the connection point together. It can be helpful if the moving boom part/counter-jib part is captured after rough alignment. This is preferably accomplished by means of one or more catching elements in the area of the moving boom part/counter-boom part.

In an advantageous embodiment, at least one catch element is implemented as a catch eye, which is provided in the assembly or operating position above the stop surface or counter-stop surface on the second connecting part or on the boom or counter-jib. The catch eye is in principle characterized by an opening through which a corresponding collecting means of the first connecting part or the tower top can be inserted, preferably in the horizontal direction.

The catching eye is sensibly dimensioned larger than the circumference or diameter of the collecting means used. During the assembly process, the boom or counter-jib can now be placed roughly in the area of the tower top and the collecting means can be inserted through the catch eye in order to ensure a rough alignment of the two components to one another.

However, the catch element, in particular the catch eye, also has an essential function during the dismantling process. After the actual connection point has been released, the connection between the boom or counter-jib and the tower top is roughly secured by the collecting device inserted through the catch eye, so that the boom or counter-jib is prevented from swinging away. This makes it possible to have the material picked up by the auxiliary crane The boom part or counter-boom part must first be aligned in an equilibrium position so that the collecting device floats freely within the catch eye. This prevents the boom or counter-jib from swinging away in an uncontrolled manner even after the collecting means has been removed.

It is particularly preferred if the catch eye is formed by an opening within a sheet metal which is perpendicular to the connecting head. For example, the sheet metal extends vertically upwards from the connection head. Alternatively, the connecting head and the catch eye can also be made in one piece.

In order to further simplify the assembly process, it is advantageous if one or more catch plates are provided in the area of the concave stop surface, i.e. in the area of the connecting socket, which simplify the bringing together of the stop surfaces, in particular the insertion of the connecting head.

In addition to the tower crane according to the invention, the present invention also relates to a method for assembling a jib or counter-jib on a tower crane according to the present invention. The process according to the invention is characterized by the following individual process steps:
Moving the boom or counter-jib, preferably using an auxiliary crane, into the area of the tower top and catching the boom or counter-jib by inserting the collecting device through the catch eye. Fine adjustment of the boom or counter-jib and merging the convex counter-stop surface with the concave stop surface. Insert the bolt through the second connecting part. for pressing the stop surfaces together can be achieved by tensioning the boom bracing. Alternatively or additionally, the load moment can be generated by lowering the boom, which in turn causes the compressive force required in the stop.

Finally, the present invention also relates to a dismantling method for releasing the connection between the boom or counter-jib and the tower crane, which is designed according to the present invention. The dismantling method according to the invention is characterized in that in a first step the bolt inserted through the second connecting part is first pulled. In this case, the connection point is only secured by the connection between the collecting device and the catching eye. In the following step, the boom or counter-jib is aligned so that the collecting means floats freely within the catching eye. In this state, it is ensured that an appropriate lifting device, for example an auxiliary crane, for receiving the boom or counter-jib grabs it at the center of gravity, so that the boom or counter-jib is prevented from swinging away in an uncontrolled manner. The collecting means can then be removed and the boom or counter-jib can be completely dismantled. Before loosening the connecting bolt inserted through the second connecting part, any tensioning on the boom/counter-jib must be released.

Figur 1:

perspektivische Seitenansichten einer erfindungsgemäßen Verbindungsstelle zwischen Ausleger bzw. Gegenausleger und Turmkran,

Figur 2:

eine Schnittdarstellung durch die erfindungsgemäße Verbindungsstelle,

Figur 3:

perspektivische Seitenansichten des am Ausleger bzw. Gegenausleger vorgesehenen zweiten Verbindungsteils,

Figur 4:

perspektivische Darstellungen des an der Turmspitze bzw. Drehbühne angeordneten ersten Verbindungsteils,

Figur 5:

eine leicht modifizierte Ausführungsform der erfindungsgemäßen Verbindungsstelle,

Figur 6:

eine Gesamtansicht eines Krans mit montiertem Ausleger/Gegenausleger und

Figur 7:

eine weitere Ansicht eines Krans mit montiertem Ausleger/Gegenausleger.

Further advantages and properties of the invention are explained in more detail below using an exemplary embodiment shown in the drawings:
Show it:

Figure 1:

perspective side views of a connection point according to the invention between the jib or counter-jib and the tower crane,

Figure 2:

a sectional view through the connection point according to the invention,

Figure 3:

perspective side views of the second connecting part provided on the boom or counter-jib,

Figure 4:

perspective views of the first connecting part arranged on the top of the tower or revolving stage,

Figure 5:

a slightly modified embodiment of the connection point according to the invention,

Figure 6:

an overall view of a crane with mounted jib/counter jib and

Figure 7:

Another view of a crane with the jib/counter jib mounted.

An exemplary embodiment of the invention will be explained in more detail below. The Figures 1 to 4 show different views of the novel connection point of the crane according to the invention, whereby the Figures 1a, 1b perspective side views of the existing connection Figure 2 a sectional view in the longitudinal direction through the existing connection Figures 3a, 3b perspective side views of the second connecting part and the Figures 4a, 4b show perspective views of the first connecting part. A single connection point is shown, but the overall connection between the boom/counter-jib and the crane tip is made via a large number of such connection points.

The first connecting part 10 is part of the crane tip or a rotating platform provided on the crane tip and is separately in the Figures 4a, 4b shown. This is designed in the form of a connecting socket 11, the inner wall 12 of which has a concave shape with a negative radius of curvature. On both sides of the first connecting part 10 in the area of the connecting socket 11, side plates 13a, 13b are attached, in particular screwed to the connecting part 10, which initially lie parallel to one another, but are angled outwards in the cantilever direction, forming an insertion funnel. The angled areas 14a, 14b form insertion aids for inserting the complementary connecting part 20 into the connecting socket 11. The side plates 13a, 13b also protrude beyond the upper edge of the first connecting part 10 and look at it There is a hole 16 at the top end for bolt reception, the purpose of which will be explained later.

The complementary second connecting part 20, separately in the Figures 3a, 3b shown, is formed by the connecting head 21, which extends at the front from the corresponding articulation area of the boom/counter-boom in the direction of the crane tip. The connecting head 21 includes a convex counter-stop surface 22, the positive radius of curvature of which is dimensioned slightly smaller than the radius of the stop surface 12.

If the connecting head 22 is inserted into the connecting socket 12, both connecting parts 10, 20 can be pivoted relative to one another about a horizontal axis due to the coordinated radii, which is particularly advantageous during the assembly process. The connection is essentially non-positive, since the second connecting part 20 or the boom/counter-jib is pulled by a bracing in the direction of the tower top or into the connecting socket 12. Opposite tensile forces are transferred by the connecting bolt 35, which is inserted transversely to the longitudinal axis of the boom through corresponding bores 15 in the side plates 13a, 13b and a central bore 25 in the connecting head 22. The connecting bolt 35 thus also forms the pivot axis of the two connecting parts 10, 20. During crane work, there is a force ratio of approximately 10:1 between compressive and tensile forces, which is why the connecting bolt 35 can be dimensioned significantly smaller due to the comparatively low tensile forces.

It is also worth noting that the width of the connecting socket 12 should be larger than the width of the connecting head 22.

On the upper peripheral surface of the connecting head 22, a sheet metal 30 extends vertically upwards and has a large-sized circular opening 31. This opening serves as a catch eye 31, which serves, among other things, to catch the boom/counter-jib during crane assembly. Will that If the jib/counter jib picked up by an auxiliary crane is initially brought close to the tip of the crane, a catch bolt 36 can be inserted as a catch means through the catch eye 31 and the bores 16 in the side plates 13a, 13b. The cantilever part/counter-cantilever part captured in this way can be more easily aligned into the final position for establishing the connection, ie the connecting head 22 is inserted into the connecting socket with the support of the insertion aids 14a, 14b. Finally, the connecting bolt 35 is inserted and the boom bracing is tensioned or the top chord strap is connected.

The diameter of the capture bolt 36 is significantly smaller than the diameter of the capture eye 31, which significantly simplifies the capture of the second connecting part. However, the safety eye also takes on a safety function during the dismantling process in order to prevent the boom or counter-jib from swinging away in an uncontrolled manner. During the dismantling process, the boom or counter-jib is picked up by the auxiliary crane and the connecting bolt 35 is pulled. This results in a comparatively small movement of the jib or counter-jib, unless it was picked up exactly at its center of gravity by the auxiliary crane. However, this oscillating movement is limited by the catch bolt 36 that is still inserted and which strikes the inner wall of the catch eye 31. In the following step, the crane driver of the auxiliary crane must align the boom or counter-jib so that the catch bolt 36 floats within the catch eye, i.e. does not hit the inner edge. If this is the case, the picked-up boom part/counter-jib part is in balance and an undesirable swinging movement after the capture bolt 36 has been pulled can be ruled out. The boom or counter-jib can then be safely lowered by the auxiliary crane.

A slightly modified embodiment of the connection point according to the invention is the Figure 5 refer to. This embodiment differs in terms of the features essential to the invention in the design of the connecting part 20. The connecting head 21 'and the catch eye 31' are in one piece here executed. The catch eye 31' also does not have a circular opening but instead has an oval or rectangular opening with rounded corners.

The Figures 6 , 7 each show an overall view of a tower crane, the boom 20 of which is mounted in area 1 by means of the connection point according to the invention on the crane tip or a rotating platform provided there. At the crane Figure 7 The non-positive connection is achieved because the second connecting part 20 (boom/counter-boom) is pulled by the bracing 2 in the direction of the tower top or into the connecting pan 12. With the crane type Figure 6 This force is caused by the load moment of the jib/counter jib.

Claims (12)

1. A tower crane, preferably a revolving tower crane, particularly preferably a top slewer, having a boom and a counterboom, wherein the boom and/or counterboom is connected in an articulated manner to the tower tip and/or slewing platform by means of at least one connection point, wherein a first connection part (10) of the at least one connection point has a concave abutment surface (12) and a second connection part (20) of the connection point comprises a convex counter-abutment surface (22), wherein the counter-abutment surface (22) of the second connection part (20) acts by means of compressive force on the abutment surface (12) of the first connection part (10) to effect a force fit connection between the connection parts (10, 20),
   characterized in that
   the second connection part (20) comprises a connection head (21) having a defined radius as a counter-abutment surface (22) ; and in that the first connection piece (10) is configured as a connection socket (11) having an inner radius adapted to the radius of the connection head (21) as the abutment surface (12).
2. A tower crane in accordance with claim 1, characterized in that the compressive force is produced by at least one boom guying (2) and/or by a load torque.
3. A tower crane in accordance with one of the preceding claims, characterized in that at least one connection pin (35) is insertable in a horizontal direction, in particular transversely to the longitudinal beam axis, for fixing the connection, in particular for removing tensile forces, with corresponding pin slots ideally being provided both at the first (10) and/or second connection parts (20).
4. A tower crane in accordance with claim 3, characterized in that a pin slot for the connection pin (35) is formed by a bore at the center of the convex counter-abutment surface (22), in particular at the center of the radius of the connection head (21).
5. A tower crane in accordance with one of the preceding claims, characterized in that the at least one connection point is arranged directly at the tower tip or at a slewing platform provided in the region (1) of the tower tip.
6. A tower crane in accordance with one of the preceding claims, characterized in that the first connection part (10) is a component of the tower tip or of the slewing platform and the second connection part (20) is arranged at the boom or counterboom.
7. A tower crane in accordance with one of the preceding claims, characterized in that at least one capturing eye (31) is provided above the abutment surface (12) or counter-abutment surface (22) at the second connection part (20) or the first connection part (10) in the assembly position, through which capturing eye at least one capturing means, in particular a capturing pin (36), extends, wherein the capturing eye (31) is preferably dimensioned as considerably larger than the periphery, in particular the diameter of the capturing means.
8. A tower crane in accordance with claim 7, characterized in that the capturing eye (31) is formed by an aperture within a metal sheet (30) that is approximately perpendicular on the connection head (21).
9. A tower crane in accordance with one of the preceding claims, characterized in that one or more capturing metal sheets are provided in the region of the concave abutment surface (12), in particular in the region of the connection socket (11), that assist the leading together of the convex counter-abutment surface (22) with the concave abutment surface (12) during the boom assembly.
10. A method of assembling a boom or counterboom at a tower crane in accordance with claims 4 and 7, comprising the following steps:

    a. Moving the boom or counterboom into the region of the tower tip and capturing the boom/ counterboom by leading the capturing means through the capturing eye;

    b. finely adjusting the boom or counterboom to lead the abutment surface and counter-abutment surface together and inserting the pin through the second connection part.
11. A method in accordance with claim 10, characterized in that a boom guying is tensioned or the load torque is produced by lowering the boom after the insertion of the pin to apply the required compressive force to the connection point.
12. A method of dismantling a boom or counterboom at a tower crane in accordance with claims 4 and 7 comprising the method steps:

    a. drawing the pin inserted through the second connection part;

    b. aligning the boom/counterboom such that the capturing means is freely suspended within the capturing eye; and

    c. pulling out the capturing means

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