GB2184409A

GB2184409A - Railway crane

Info

Publication number: GB2184409A
Application number: GB08628887A
Authority: GB
Inventors: Johann Brorkens; Hans Wagemann
Original assignee: Fried Krupp AG
Current assignee: Fried Krupp AG
Priority date: 1985-12-20
Filing date: 1986-12-03
Publication date: 1987-06-24
Also published as: GB8628887D0

Abstract

Railway cranes (see Fig. 1) having an undercarriage (2) carried by two bogies and an upper carriage (3) pivotably mounted thereon with a jib (4) are equipped, for security against derailing and optimisation of the loading of the upper structure, with slide blocks (12) allocated each to one bogie side, through which the undercarriage (2) is supported on the bogies (1) after a predetermined clearance is taken up. In order to minimise the wheel load or wheel assembly load increases occurring on displacements of the centre of gravity of the crane, for example by jib movements or loadings, and thus to increase the load capacity of the crane, the slide blocks (12) are made displaceable in the vertical direction and securable, singly or plurally. Displacement may be by means of hydraulic cylinder drive mechanisms or mechanical spindle drive mechanisms (13) connected to a control system such that on displacement of the centre of gravity of the crane equal loading of several slide blocks or slide block groups and thus of the corresponding wheels or wheel assemblies (6) is retained. For normal transport of the crane the blocks (12) can be locked in position by engagement of pins 14 in recesses in the blocks.

Description

SPECIFICATION Railway crane The invention relates to a railway crane having an undercarriage carried by two bogies and an upper carriage pivotably mounted thereon with a jib, in which the undercarriage is supported on the bogies each through a ball-bearing socket and two slide blocks on the undercarriage each allocated to one bogie side.

In known railway cranes of this kind the slide blocks are fixedly arranged on the undercarriage and in the unloaded condition, that is to say for example in a train journey, possess a fixed clearance from the slideways, which is necessary for the security of the vehicle against derailing. In the case where the centre of gravity of the railway crane is in the middle of the vehicle, equal wheel assembly loads and equal wheel loads occur. However in crane operation a shift of the centre of gravity in the longitudinal direction, that is to say in the track direction, must be expected. Consequently in the case of a straight track position and a jib position in the direction of the track, when the crane is unsupported or is travelling with load suspended, the wheel assembly loads are different, but the two wheels of each wheel assembly are still equally heavily loaded.If in addition the jib carries out a horizontal pivot movement, the wheel loads vary in dependence upon the pivot angle and the shift of centre of gravity. For reasons of security against derailing, of the permissible loading of the upper structure and of the component strength of the crane vehicle, the wheel pressure must not exceed a specific value.

The support of the bogie through the fixed slide blocks, after the play is taken up, means that one wheel of the most heavily loaded wheel assembly must additionally take up the greatest part of the support force from the lateral shift of the centre of gravity. Thus here the maximum permissible wheel pressure is very quickly reached.

The aim of the present invention is to remove this disadvantage and produce an arrangement which results in a more uniform load distribution and thus wheel pressure distribution, that is leads to a higher load capacity of the crane. Accordingly for a railway crane of the initially stated kind it is proposed that the slide blocks are made displaceable in the vertical direction and securable, singly or pluraily. If then for example in a load case with pivoted jib, the slide blocks on the more heavily loaded bogie are shifted upwards so far, that is the clearance is increased, then despite the occurrence of twisting the slide blocks do not come into contact with the slideways, and the force which is introduced can here take place only through the centrally dis posed ball-bearing socket.Therefore the force is distributed more uniformly to the wheels of this bogie than if the slide blocks were supported on the slideways.

If then in the more lightly loaded bogie the slide blocks are lowered, that is the clearance is taken up, a three-point mounting is thus achieved. The support force from the lateral shift of the centre of gravity is taken up in a higher proportion by the wheels of the less heavily loaded bogie side. Accordingly the crane becomes capable of more performance, for a higher support force can be taken up before the maximum wheel load limit is reached. A higher support force signifies a greater permissible pivot angle for equal loading or a higher permissible load for the same pivot angle.

So that the clearance of the slide blocks from the slideways prescribed for the train journey remains easily reproducible and securely settable, a blocking device for a specific position is provided for the slide blocks, for example in the form of a blocking bolt which can be driven transversely of the direction of displacement into the slide block. During crane operation the blocking bolt is driven out, possibly by a hydraulic cylinder.

In a further development of the invention it is proposed that hydraulic cylinder drive mechanisms, mechanical spindle drive mechanisms or the like are provided for the displacement of the slide blocks in the undercarriage. By means of these drive mechanisms the individual slide blocks can be driven in a simple manner in each case into the most expedient position. The drive mechanisms can be used at the same time to orientate the crane horizontally, if for example it stands on a track elevation. For this purpose the slide blocks lying on the downhill side are lowered and the slide blocks lying on the uphill side are raised until all components above the bogies are pivoted about the ball-bearing sockets into the horizontal position.

It is also advisable to design the drive systems for the displacement of the slide blocks and connect them to a control system in such a way that on displacements of centre of gravity of the crane a largely equal loading of several slide blocks or slide block groups is retained. Due to such an arrangement it is possible to achieve a better wheel load distribution with simultaneously improved standing stability in such a manner that even on the more heavily loaded bogie the slide block on the less loaded side or both slide blocks is or are lowered into contact with the slideways.

In this case a pressure regulation in the drive mechanisms additionally takes place through the control system so that the moment from the lateral displacement of the centre of grav ity is taken up differently by the individual wheels only to the extent which is necessary according to the maximum permissible wheel loads.

Between the axle ends of the wheels and the bogie there are provided spring blocking cylinders to set the axle suspension out of action in crane operation, so that then no uncontrolled shift of centre of gravity and variation of wheel load are effected by the axle suspension.

An example of embodiment of a railway crane designed in accordance with the invention is illustrated in the drawings, wherein: Figure 1 shows the crane in lateral elevation, Figure 2 shows the crane in cross-section through a bogie in the train journey operating position, Figure 3 shows the crane in cross-section through a bogie with slide block lowered, Figure 4 shows the crane in cross-section through a bogie with slide block raised, and Figure 5 shows the crane in cross-section through a bogie with undercarriage oriented horizontally on an elevated track.

The railway crane is equipped with two bogies 1 which carry an undercarriage 2 on which an upper carriage 3 is rotatably mounted with a vertically pivotable jib 4.

Wheels 6 secured on axles 5 are mounted through wheel bearings 7 in the bogie 1 and are suspended through springs 8. Spring blocking cylinders 9 serve to set the suspension out of action in crane operation according to Fig.s 3, 4 and 5. Each bogie 1 is connected through a ball-bearing socket 10 with the undercarriage 2. Moreover on the bogie 1 there are arranged slideways 11 opposite to which there lie slide blocks 12 in the undercarriage 2. The slide blocks are vertically dis placeable by hydraulic cylinder drive mecha nisms or mechanical spindle drive mechanisms 13 connected to a control system (not shown). A blocking bolt 14 can be driven by a hydraulic cylinder 15 transversely of the di rection of displacement into the slide block 12 in order thus to fix the slide block in a position in which a clearance predetermined for the train journey of the railway train, corre sponding to the distance X in Fig. 2, is pre sent between the undercarriage 2 and the bo gie 1, that is between slide block 12 and slideway 11.

Claims

1. A railway crane having an undercarriage carried by two bogies and an upper carriage with a jib and mounted rotatably thereon, in which the undercarriage is supported on each of the bogies through a ball-bearing socket and two slide blocks on the undercarriage each allocated to a bogie side, beneath which blocks there lie related slideways on the bo gie, the slide blocks being displaceable in the vertical direction and securable, individually or plurally.

2. A railway crane according to claim 1, in which a block device for a particular position is provided for the slide blocks, for example in the form of a blocking bolt which can be driven transversely of the displacement direction into the slide block.

3. A railway crane according to claim 1 or 2, in which hydraulic cylinder drive mechanisms, mechanical spindle drive mechanisms or the like are provided for the displaceability of the slide blocks in the undercarriage.

4. A railway crane according to claim 1, 2 or 3, in which the drive systems for the displacement of the slide blocks are designed and connected to a control system in such a way that on displacements of centre of gravity of the crane a largely equal loading of several slide blocks or slide block groups is retained.

5. A railway crane according to any one of the preceding claims, in which between the axle ends of the wheels and the bogie there are provided spring blocking cylinders to set the axle suspension out of action in crane operation.

6. A railway crane according to claim 1 substantially as hereinbefore described with reference to the drawings.