Abstract:
A crane for raising and lowering a load, which crane includes a vehicle frame with end areas and a slewing device arranged on the vehicle frame. The slewing device includes at least two basic slewing columns slewable by 360°, mounted on the vehicle frame in the vehicle frame end areas. Additionally, a separate articulated slewing arm having at least two elements is located on each basic slewing column.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The invention relates to a crane, particularly a track-bound mobile crane, with a slewing device arranged on a vehicle frame for a load to be picked up and set down again. 
     2. Discussion of the Prior Art 
     Cranes of the mobile type, such as street cranes or track-bound cranes, are known which have a superstructure located centrally or almost centrally on the undercarriage, whereby various drive units, such as diesel engines and hydraulic pumps, are arranged on the rotatable superstructure (DE-OS 32 27 157). 
     However, cranes of this type can only be used for jobs in a limited fashion, as determined by the jib head. For example, the jib head is equipped with a telescopic jib, the reach of which is, however, determined by the center of gravity of the entire vehicle. It is therefore not possible to transport particularly long loads on the one hand and loads of smaller dimension that are short and heavy on the other. 
     SUMMARY OF THE INVENTION 
     Accordingly, it is an object of the present invention to provide a crane, particularly a mobile crane, which can be universally used for a large number of jobs, various lengths of load and various load sizes. The focus is to be especially on the functions needed in track and bridge construction. 
     According to the invention, this object is attained in a crane having a slewing device that consists of at least two basic slewing columns, slewable by 360 degrees, which are mounted, respectively, on the vehicle frame in the two vehicle frame end areas centric or equidistantly eccentric to the central longitudinal axis of the Vehicle frame. Additionally, an articulated slewing arm with at least two elements is attached to each basic slewing column. Such a crane is especially suitable for long and heavy loads, such as occur in track and bridge construction, for example. 
     In another embodiment of the invention, along with the eccentric basic slewing columns, at least one guidance carrier for trolleys, which extends in the longitudinal direction, is supported on the vehicle frame. The crane hereby serves on the one hand as a transport vehicle, while on the other hand the guidance carrier represents an additional element for later permitting the transport of long and heavy loads. 
     Advantageously, the guidance carrier is equipped with trolleys on both cross-sectional sides. This makes it possible to hang and carry long and heavy construction parts or loads symmetrically on the underside of the guidance carrier. 
     In a further embodiment of the invention, a gripper for catching and holding the guidance carrier is attached to each slewing arm in a rotary-adjustable manner. The load on the guidance carrier can therefore be swung out via the slewing arms as desired toward one side or the other, i.e., picked up and set down again. 
     Additionally, the basic slewing columns are height-adjustable. This height adjustability performs a double function, in that both the guidance carrier and the load can be adjusted in height. 
     In yet a further embodiment of the invention, each of the basic slewing columns is located on a rotatable platform on the vehicle frame. This facilitates the setting of slewing angles in the horizontal, so that the guidance carrier can be set not only parallel to the travelling direction of the crane, but also obliquely in the sense of a curve. 
     The invention is further improved by the fact that for the transport of the crane, two guidance carriers are stacked one atop the other on the vehicle frame and that during use the two guidance carriers are connectable to one another arranged one behind the other by means of the slewing devices. In this way, the greatest possible length of the load pick-up means is achieved. 
     For displacement of the center of gravity outside of the crane support area, it is further advantageous that in the area of the slewing devices, on both sides on the vehicle frame, struts with supporting plates are provided which can be swung out on arms. 
     Furthermore, jobs can be supervised or carried out and directed in that there is an operator cabin arranged in each of the vehicle end areas eccentric to the central longitudinal axis of the vehicle frame. Here it is advantageous that the two operator cabins are arranged on the same longitudinal side of the vehicle frame. 
     An advantageous organization of the structural space available on the crane is furthermore achieved by providing ballast weights or ballast tanks on the vehicle frame between the slewing devices. 
     The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of the disclosure. For a better understanding of the invention, its operating advantages, and specific objects attained by its use, reference should be had to the drawing and descriptive matter in which there are illustrated and described preferred embodiments of the invention. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a side view of the inventive crane in transport status; 
     FIG. 2 is a top view of the crane as in FIG. 1; 
     FIG. 3 is a side view of the crane in operation, working with two guidance carriers connected to one another; 
     FIG. 4 is a top view on the operating status of the crane as in FIG. 3; 
     FIG. 5 is a side view of the crane during the job, whereby the two guidance carriers are connected to one another in a different direction; 
     FIG. 6 is a top view of the working example of the crane as in FIG. 5; 
     FIG. 7 is an additional example of the crane, in side view, with height-adjustment of the slewing devices; 
     FIG. 8 is a top view for FIG. 7, with another possible use, for example, of the crane for curved runs; and 
     FIGS. 9-16 respectively show a front view of individual work steps or transport positions. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The crane, particularly a railway crane, has a vehicle frame 1 with buffers 1a and 1b and can be moved on track pairs 2 by means of bogies 3 with wheel sets 4 (FIG. 1). On the vehicle frame 1 there are slewing devices 5 for loads that are to be picked up and set down again, such as, for example, sections of track 6 (track with cross-ties; FIGS. 3 and 4) having lengths of, for example, 24 m, switch elements 7 and the like (FIGS. 13 and 14), and cross-ties 8 (FIG. 15). 
     The slewing device 5 consists of at least two basic slewing columns 9, 10, which are mounted in the two vehicle frame end areas 1c and 1d either centric (FIGS. 3, 5 and 7) or at equal distances 1e eccentric to the central longitudinal axis 19 of the vehicle frame. Each basic slewing column 9, 10 carries an articulated slewing arm 11 with at least two elements. The arm element 11a and the arm element 11b are connected, respectively, to the basic slewing columns 9, 10. The last arm element 11b carries a gripper 12 for catching and holding a guidance carrier 14 extending in the longitudinal direction 13 for multiple trolleys 15. The guidance carrier 14 at first rests through its weight on the vehicle frame 1, whereby two guidance carriers 14 can be stacked one atop the other (FIG. 1). The guidance carrier 14 is equipped on both cross-sectional sides 14a, 14b (FIG. 2) with the trolleys 15. The gripper 12 is rotatably attached to the last arm element 11b. 
     The basic slewing columns 9, 10 are height-adjustable and may, for example, consist of telescoping units. At the same time, these basic slewing columns 9, 10 are respectively rotatably mounted on a rotatable platform 16 on the vehicle frame 1. FIGS. 1 and 2 show the crane in its transport position, while in the application shown in FIGS. 3 and 4 the guidance carriers 14 are arranged one behind the other by means of an auxiliary carriage 17 and a connection 18. The crane (-carriage) and the auxiliary carriage 17 are thereby coupled to one another, i.e., the buffers 1a, 1b stand against one another. 
     Struts 21 are attached in the area of the slewing devices 5, respectively, on both sides on the vehicle frame. The struts 21 have attached supporting plates 22 and can be swung out on arms 20. 
     After the guidance carriers 14 have been connected one behind the other, they hang in the slewing devices 5 and can therefore (FIGS. 5 and 6), for example, be swung over the track of a track pair 2 that is to be laid parallel. For this purpose, the particular track section 6 hangs on the cable-trolleys or trolleys 15. At this stage, the slewing arms with the arm elements 11a and 11b, to which the grippers 12 are attached, are swung out accordingly. All work steps are controlled from one of the operator cabins 23 located respectively in the vehicle frame end areas 1c, 1d eccentric to the central longitudinal axis 19 of the vehicle frame. Advantageously, the two operator cabins 23 are arranged on the same longitudinal side 24 (FIGS. 4, 6 and 8) of the vehicle frame 1. In addition, ballast weights or ballast tanks 25 are attached to the vehicle frame 1 between the slewing devices 5. 
     In order to lay the track sections 6 on curves, the slewing devices 5 are slewed individually on the platform 16; and to set the angles 26 on up-grades and down-grades, the basic slewing columns 9, 10 are held individually or telescoped (FIGS. 7 and 8). 
     The crane is especially suitable for internationally prescribed gauges 27. In the transport position (FIG. 9), the operator cabin 23 and the stacked guidance carriers 14, in particular, are located within the gauge 27. Individual guidance carriers 14 may also remain in the transport position on the slewing devices 5, the basic slewing columns 9 and 10, the slewing arms 11 with arm elements 11a, 11b, as well as on grippers 12 including the trolleys 15 (FIG. 10). 
     Gauges 28 according to various national regulations also accommodate, along with the components already mentioned, cross-ties 8 on the trolleys 15 (FIGS. 11 and 12). 
     In addition, complete switch elements 7 can be carried within the gauge 28 or 29 (FIGS. 13 and 14). 
     For the installation of cross-ties (FIGS. 15 and 16), the arms 20 with the struts 21 and supporting plates 22 are swung out on both sides of the vehicle frame 1, so that the slewing devices 5 located over the struts 21 are fully supported. The complete extended outswing of the slewing arms 11 and the arm elements 11a, 11b can hereby be taken advantage of.