Crane with auxiliary boom and method for erecting an auxiliary boom

Abstract

The invention relates to a crane (1), in particular a mobile crane or a crawler crane, comprising a main jib (13) and a secondary jib (3) and a setting-up support (40), which is arranged on an upper carriage (12) of the crane and is connected to a guy rope (6) of the secondary jib via a cable adjuster (5), wherein at least one compression strut (311) is provided, which is articulated on the secondary jib or on a pivot axis of the secondary jib, in order to temporarily receive the cable adjuster and / or the guy rope, wherein the receiving position of the compression strut is designed in such a way that the cable adjuster or the guy rope can be lifted independently from the compression strut at a certain setting-up angle of the secondary jib.

Description

TECHNICAL FIELD

[0001] The invention relates to a crane, in particular a mobile crane or a crawler crane, having a main jib and a counterjib as well as an erection support which is arranged on the upper carriage of the crane and is connected to the guy device of the counterjib via a cable adjuster. BACKGROUND

[0002] Lattice mast type large cranes are generally composed of a main jib and a counterjib. The jib system is mounted on an upper carriage which is rotatably mounted on a mobile lower carriage. For erecting the crane, the main jib is assembled with the aid of a counterjib which has already been assembled and erected, wherein the counterjib serves as a support for the cable adjuster for erecting the main jib.

[0003] In the type of crane previously known, an adjustable erection support which is mounted on the upper carriage is required for assembling the counterjib. This is illustrated in the schematic drawings of the crane in Figure 1a , Figure 1b , which show a crane having a lower carriage 11 and an upper carriage 12. The adjustable erection support 4' is connected to the jib head of the counterjib 3 via a guy device 6. The cable adjuster 5 is attached directly to the upper carriage 12 and is connected to the guy device 6. By retracting the cable adjuster 5, the counterjib 3 can be erected. The reason for the chosen configuration is that the crane can be operated without the counterjib 3. A prerequisite is the adjustable erection support 4'. The chosen configuration is used in particular in cranes which carry loads of up to 1500 tons.

[0004] In large cranes which carry loads of more than 1500 tons, it is stipulated that a counterjib must be used. For erecting the counterjib, various types of required erection supports 4 have been developed for such cranes. The most widely used design is a fixed erection support 4 which is arranged on the upper carriage 11 and serves as a fixed point and pressure support for the cable adjuster 5 during erection of the counterjib 3. This principle is shown in Figure 2a , Figure 2b . The solution with the adjustable erection support 4' as shown in Figure 1a , Figure 1b is ruled out here because of the high weight required for such an erection support 4' and the space problem on the upper carriage. SUMMARY

[0005] The present application attempts to improve the existing solutions.

[0006] This object is achieved by a crane, in particular a mobile crane or a crawler crane, having the features of claim 1. Advantageous embodiments of the crane are the subject of the dependent claims. The features of claim 6 provide a novel and improved method for erecting a secondary boom. Advantageous embodiments of the method are the subject of the dependent method claims.

[0007] According to the invention, it is proposed to supplement a crane structure comprising a cable adjuster arranged on an upper carriage and an erection bracket by an additional pressure strut hinged to the secondary boom, in particular in the region of the base of the secondary boom or in the region of the pivot axis of the secondary boom. The pressure strut is preferably pivotably, in particular pivotably about a horizontal axis, hinged. It is also conceivable for the pressure strut to be hinged directly on the pivot axis of the secondary boom. In this case, the pivot axis of the pressure strut can be coaxial with the pivot axis of the secondary boom. The cable adjuster is usually connected to a guy device in order to be able to change the erection angle of the secondary boom by actuating the cable adjuster. The guy device usually extends from the cable adjuster to the tip of the secondary boom.

[0008] At least during the erection process, the pressure strut contacts the cable adjuster and / or the guy device and receives the cable adjuster and / or the guy device at its free end, in particular via suitable bearing points. Thereby, the cable adjuster and / or the guy device can be pushed away from the rear of the secondary boom by means of the pressure strut.

[0009] Due to the compression force additionally exerted by the pressure strut on the cable adjuster / guy device, the size of the used erection bracket at the tail of the upper carriage or the turntable can be significantly smaller. The geometry of the lever arm and the generation of the required erection moment are mainly generated by the employed pressure strut. In contrast, according to the prior art solutions, the erection bracket has to protrude from the upper carriage in the vertical direction quite far in order to be able to generate a sufficient erection moment for the secondary boom at all.

[0010] A further advantage of the invention is that in the geometry according to the invention formed by the erection bracket, the cable adjuster, the pressure strut and the guy device, a change in the angle of the secondary boom causes a smaller change in the lever arm, which has a positive influence on the overall process, in particular when in the planar position.

[0011] The saving in size of the erection bracket also brings corresponding advantages. The changing geometry during power transmission leads to a reduction in the necessary retraction length of the cable adjuster for erecting the secondary boom.

[0012] According to a preferred embodiment, the pressure strut is hinged to the rear side of the secondary boom. It has proven advantageous for the pressure strut to be pivotably hinged on the rear side of the secondary boom in the region of the arm base of the secondary boom. This position of the pressure strut has the best influence on the resulting lever arm during the erection of the secondary boom.

[0013] Likewise, according to the application, the connection between the pressure strut and the cable adjuster or the guy rope device is only temporary, i.e. the cable adjuster or the secondary arm guy rope device can independently lift itself from the pressure strut. It is particularly provided that the cable adjuster / guy rope device is operatively connected to the pressure strut only at the beginning of the erection process of the secondary arm. From a specific erection angle of the secondary arm, the cable adjuster / guy rope device independently lifts itself from the pressure strut. In order to prevent the pressure strut from toppling over after the cable adjuster has been lifted, corresponding locking points can be provided. The toppling over can occur in both directions.

[0014] Advantageously, the cable adjuster or the guy rope device is placed on a suitable bearing point of the pressure strut, which allows the lifting at a specific erection angle of the secondary arm, but by means of the cable adjuster a force can be exerted on the pressure strut which causes a pivoting movement of the pressure strut. It is conceivable that this can be achieved by corresponding locking means, such as a guy rope device or a stop, in the area of the bearing point.

[0015] The bearing point of the pressure strut is preferably adapted to receive and support the rolling axis of the upper pulley of the cable adjuster. In the ideal case, the operation of the cable pulley is thereby not impaired, so that the cable adjuster operates unrestricted. For example, it is conceivable that the bearing point allows the rolling axis to be lifted in the longitudinal direction of the pressure strut, but the relative movement of the upper pulley transversely to the longitudinal axis of the pressure strut is prevented by a corresponding stop on the side. Likewise, it is conceivable that the upper pulley of the cable adjuster can be temporarily fixed to the pressure strut by means of a locking mechanism.

[0016] The erection support used can be designed as a fixed, in particular triangular, erection support on the upper carriage. Preferably, the erection support is mounted at the rear end of the upper carriage. In addition to the cable adjuster, the erection support likewise can receive the retraction mechanism of the cable adjuster.

[0017] According to an advantageous embodiment of the crane, the crane is designed as a mobile crane or a crawler crane. Here, a suitable lattice jib serves as the secondary arm. For example, the main jib is a lattice jib.

[0018] In addition to the crane according to the application, the application also relates to a method for erecting a secondary arm of a crane according to the application. According to the application, it is proposed that at the beginning of the erection process of the secondary arm, the cable adjuster or the guy rope device is received by the bearing point of the pressure strut at a small erection angle of the secondary arm in order to push the received cable adjuster or guy rope device away from the rear of the secondary arm by means of the pressure strut. At a defined erection angle of the secondary arm, the cable adjuster / guy rope device is intended to be lifted independently from the pressure strut.

[0019] The advantages of the far-reaching extension achieved by carrying out the method have already been explained above with reference to the crane. In order to avoid repetitions, further embodiments are therefore omitted here.

[0020] In order to carry out the method, initially a first step is proposed in which the auxiliary boom is mounted on the upper carriage together with the pressure strut which is already articulated on the upper carriage. In a subsequent step, it can be provided that the pressure strut is turned forward in the direction of the tip of the auxiliary boom. In a further step, the cable adjuster is likewise pulled forward in order to place it on the bearing point of the pressure strut provided for this purpose. At the same time, the guy device of the auxiliary boom is connected, in particular bolted, to the cable adjuster.

[0021] In a subsequent step, it can be provided that the pressure strut is initially erected to a certain angle by means of the retraction mechanism of the cable adjuster. This is achieved by means of corresponding stop or locking means in the region of the bearing point, so that a tensile force transmission from the cable adjuster to the pressure strut is provided. At the same time, the tensile force causes a tensioning of the guy device of the auxiliary boom.

[0022] In a subsequent step, the auxiliary boom can be erected by means of a further retraction of the retraction mechanism of the cable adjuster, i.e. to a certain desired erection angle. From the certain auxiliary boom angle, the cable adjuster is automatically lifted from the pressure strut. The pressure strut is no longer required during further crane operation. Only the guy device and the cable adjuster are used for the support and luffing of the auxiliary boom. The lowering of the auxiliary boom takes place in reverse order. Due to the above-mentioned locking points, the pressure strut remains in a position in which the pressure strut can again pick up the upper pulley at a certain placement angle. BRIEF DESCRIPTION OF DRAWINGS

[0023] Further advantages and properties of the application will be explained in detail below with reference to the exemplary embodiments shown in the drawings. In the drawings:

[0024] Figure 1a , Figure 1b , Figure 2a , Figure 2b : different examples of a crane according to the prior art are shown,

[0025] Figures 3a to 3f : views of a crane according to the application are shown in time sequence during the execution of the method of the application,

[0026] Figure 4 : a side view of a crane according to the application with an erected boom and a mounted main jib, and

[0027] Figures 5a to 5h : various comparisons of a known crane with a crane according to the application in order to illustrate the advantages of the application. DETAILED DESCRIPTION

[0028] As Figure 1a , Figure 1b , Figure 2a , Figure 2b indicated in the introduction. Repetitive descriptions are therefore omitted.

[0029] The construction according to the invention is shown in Fig. 3 and Figure 4 . In the large drawing in Figure 4 , the individual crane components are best recognized. The large crane shown in Figure 4 comprises a lower carriage 11 (here a caterpillar travelling device), and a turntable 12 rotatably arranged on the lower carriage. A derrick sub-arm 3 is variably hinged on the turntable 12. A main cantilever 13 is likewise variably mounted on the turntable and is configured as a lattice mast.

[0030] At the rear end of the upper carriage 2, a mounting bracket 40 is present, which is fixedly mounted on the upper carriage 12 as a rigid structure. The mounting bracket 40 is essentially triangular. At the highest point of the mounting bracket 40, a cable adjuster 5 is mounted. The length of the cable adjuster 5 is adjustable by means of a retraction mechanism 5a likewise mounted on the mounting bracket 40.

[0031] A guy rope device 6 consisting of individual guy rope stakes is directly with a sheave 51 bolted to the cable adjuster 5. By actuating the retraction mechanism 5a, i.e. by retracting the cable, the length of the cable adjuster 5 is reduced, whereby the guy rope device can be tensioned, the length changed, and the derrick 3 can be varied in amplitude.

[0032] The pressure strut 311 according to the invention is mounted on the hinged bottom of the derrick 3 (Anlenkfuβ) so as to be pivotable about a horizontal axis. The free end of the pressure strut is provided with a suitable bearing point 311a so as to receive the upper sheave 51 and exert a compression force on the pressure strut 311.

[0033] The assembly or lowering process of the derrick 6 is explained using the crane states shown in time sequence in Figures 3a to 3f . In the first step as shown in Figure 3a , the sub-arm hinge 31 of the derrick 3 is mounted on the turntable 12. The pressure strut 311 is already pre-mounted on the sub-arm hinge 31. The disassembly and lowering process takes place in reverse order Figures 3f to 3a .

[0034] In the second step as shown in Figure 3bIn the subsequent method steps shown, the pressure strut 311 is flipped forward in the direction of the boom tip. Simultaneously, the cable adjuster 5 is extended by deploying the take-up mechanism 5a, and the upper pulley 51 is also pulled forward in the direction of the boom tip, so that its rolling axis can be received by the support point 311a of the pressure strut. At the same time, the upper pulley 51 is attached to the rope device 6 of the boom 3.

[0035] In such Figure 3c In the next step of the method shown, the pressure strut 311 is erected by actuation of the retraction mechanism of the cable adjuster 5, specifically by pivoting backward in the direction of the erection support 40. Therefore, the rope device 6 of the boom 3 is simultaneously tensioned.

[0036] The auxiliary boom 3 can be erected by further retracting the cable of the cable adjuster 5 using the retraction mechanism 5a, such as... Figure 3d As shown in the image. Figure 3a The installation angle of the boom 3 is also roughly shown, at which the upper pulley 51 of the cable adjuster 5 is exactly at the support point 311a on the pressure support 311, but has already begun to lift from that point. This is achieved by further installing the boom 3... Figure 3a In the position shown, the cable adjuster 5 is fully raised from the pressure strut 311. From this moment on, the pressure strut 311 is no longer functional and remains in place by means of a locking device. For completeness, Figure 3f The required end position of boom 3 is also shown. This view is in principle consistent with... Figure 4 The views are the same, except that the latter shows the main cantilever 13 already installed. The known retraction press 312 for the auxiliary boom 3 is still necessary, and... Figures 3a to 3f and Figure 4 As shown in the image.

[0037] Therefore, during normal crane operation, neither the cable adjuster 5 nor the rope pulling device 6 contacts the pressure strut 311. Thus, the pressure strut remains inactive throughout crane operation and is only needed when the boom 3 is being erected.

[0038] exist Figures 5a to 5h In this paper, a schematic diagram of the crane according to the present invention is compared with the crane construction of the prior art in order to visualize the advantages of the present invention. Figure 5a , Figure 5b The comparison is used to illustrate the installation of support frame 4 according to the prior art. Figure 5a ) and the mounting bracket 40 according to the present invention Figure 5b) of the ratio of the height of the two erection brackets 4, 40. It is clear that there is a clear difference in the height of the two erection brackets 4, 40. The erection bracket 40 is a simpler, smaller fixed erection bracket 40. This leads to clear savings in weight and cost during manufacture. In order to obtain a sufficient lever arm H during erection of the jib arm 3, it is necessary in the prior art ( Figure 5a ) to design the erection bracket 40 relatively large and high. By using the pressure strut 311 ( Figure 5b ) described here, the erection bracket 40 at the rear of the turntable can be designed significantly smaller.

[0039] At the same time in the crane according to the application, significantly smaller lengths L are required for the cable length in the retraction mechanism of the cable adjuster 5. A direct comparison of the fixed erection bracket 4 of conventional construction ( Figure 5d ) with the crane structure of the application described here (according to Figure 5c ) shows that the cable length L required for erection by means of the retraction mechanism 5a is shorter than Figure 5d . The shorter length L is increased considerably by the roping of the cable of the cable adjuster 5. The shorter length L is due to the smaller erection bracket 40 in the solution described here ( Figure 5c ), which leads to a more favourable erection geometry.

[0040] Furthermore, the solution according to the application also provides a better lever arm H' (see Figure 5e ) for the cable adjuster 5 when the jib arm 3 is being erected (a change in the angle of the jib arm 3 causes a smaller change in the lever arm). When the jib arm 3 of a conventional crane according to Figure 5f is lowered further, for example by 1 degree, the angle change causes the lever arm to decrease more than in the case of the crane according to the application (as shown in Figure 5e ). The lever arm H' relevant here is the perpendicular distance between the centre line of the cable adjuster 5 and the jib arm articulation point.

[0041] In addition, there is a better geometry in the crane according to the application ( Figure 5g ) compared with the conventional crane ( Figure 5h ). Due to the shorter fixed erection bracket 40, a better lever arm H" is obtained in some jib arm positions, as shown from the comparison of Figure 5h and Figure 5g . With the same cantilever length and upper carriage length, the lever arm H" is longer in the view of Figure 5g than the lever arm H" of Figure 5h , i.e. a greater torque can be generated in the guy rope 6 with the same force. The lever arm H' relevant here is the perpendicular distance between the cantilever guy rope 6 and the jib arm articulation point.

Claims

1. Crane, comprising a main jib and a sub jib and a setting support, which is arranged on an upper carriage of the crane and is connected to a guy line device of the sub jib via a cable adjuster, characterized in that at least one pressure strut is provided, which is hinged to the sub jib or on a pivot axis of the sub jib, to temporarily receive the cable adjuster and / or the guy line device, wherein a receiving point of the pressure strut is designed in such a way that the cable adjuster or the guy line device can be lifted independently from the pressure strut with a specific setting angle of the sub jib, in particular, wherein the specific setting angle of the sub jib occurs after the sub jib is at least partially set. The pressure strut is pivotably hinged to the rear side of the sub jib in the region of the arm base of the sub jib or of its pivot axis. The receiving point of the pressure strut for receiving the cable adjuster comprises a locking device or a stop for the received cable adjuster / guy line device to be able to exert a pulling force on the pressure strut by means of the cable adjuster, which causes a pivoting movement of the pressure strut.

2. The crane of claim 1, wherein, A rolling axle of an upper pulley of the cable adjuster can be received by means of the receiving point of the pressure strut, wherein a locking mechanism can be provided for temporarily fixing the rolling axle at the receiving point.

3. The crane of claim 2, wherein, The pressure strut can be pivoted about a horizontal axis.

4. The crane of claim 3, wherein, The pressure strut is pivotably hinged to the arm base of the sub jib.

5. The crane of claim 2, wherein, The setting support is fixedly mounted on the setting support.

6. The crane of claim 2, wherein, The setting support is designed as a setting support which is fixed on the upper carriage and is mounted at the rear end of the upper carriage, wherein the setting support receives a take-up winch of the cable adjuster.

7. The crane of claim 1, wherein, The sub jib is a lattice jib.

8. The crane of claim 7, wherein, The setting support fixedly supports the cable adjuster at a position away from the sub jib after setting the sub jib.

9. The crane of claim 1, wherein, The setting support comprises a first arm and a second arm, wherein a fixed angle is formed between the first arm and the second arm, and wherein the first arm is connected to the second arm at a vertex of the sub jib.

10. The crane of claim 1, wherein, 12. Method for setting a sub jib of a crane according to claim 3, comprising:

11. The crane of claim 1, wherein, The cable adjuster or the guy line device is received by the receiving point of the pressure strut with a small setting angle of the sub jib at the beginning of the setting process; The pressure strut is pushed away from the rear part of the sub jib by means of the pressure strut, and The cable adjuster or the guy line device is lifted independently from the pressure strut with a defined setting angle of the sub jib, which occurs after the sub jib is at least partially set. In a first step, the sub jib is mounted on the upper carriage together with the pressure strut. After assembling the sub jib, the pressure strut is flipped forward in the direction of the sub jib tip, the cable adjuster is connected to the guy line device and placed on the receiving point.

13. The method of claim 12, wherein, The pressure strut is set and the guy line device is tensioned by taking up the take-up mechanism of the cable adjuster.

14. The method of claim 13, wherein, ​ 15. The method of claim 14, wherein, ​ 16. The method according to the preceding claim 15, characterized in that, By retracting the retraction mechanism of the cable adjuster to erect the sub-arm.

17. The method of the preceding claim 12, characterized by, Connecting the pressure prop to the cable adjuster or the guy device for erecting the sub-arm only.

Images