GB2100207A - Rail vehicle machine particularly for track maintenance or surveying - Google Patents

Abstract

The vehicle has at least one supplementary undercarriage 14 which can be lifted from or lowered onto the rails, to alter the axle loads on the normal running gear or to increase the wheel base. The additional undercarriage 14 is mounted on a sub-chassis 9 which extends longitudinally and is pivoted to the main chassis 5 by a universal joint 10 close to the main running gear 2, 3. <IMAGE>

Description

SPECIFICATION A travelling on-track machine, more particularly a track-measuring or track maintenance machine This invention relates to a travelling on-track machine, more particularly a track-measuring or track maintenance machine, for surveying or working on a railway track comprising a chassis guided on the track by an on-track undercarriage arrangement comprising several undercarriages and further comprising at least one undercarriage optionally supportable on the track through an adjustment drive and, optionally, a control system for activating the adjustment drive as required to reduce or increase the respective undercarriage axle loads.

In one known machine in the form of a heavy ballast cleaning machine (G.B. Patent Spec.

2025871) the undercarriage optionally supportable on the track in the form of a single idle axle assembly is arranged at either end of the machine chassis solely for periodically transmitting fractions of the weight of the machine. The hydraulic adjustment drives used for the vertical adjustment of the idle axles are designed to be activated as required through a control system. A guide slot extending transversely of the longitudinal axis of the machine is provided in a guide plate connected to the machine chassis, a guide pin of the idle axle assembly being guided in this guide slot so that satisfactory travel of the machine is guaranteed even around curved sections of track.In order also to obtain relatively high in-transit speeds for the heavy track maintenance machine with minimal dynamic forces acting on the track, the vertically adjustable idle axles are designed to be lowered on to the track for the in-transit run, thus reducing the axle load of the drive axles. By contrast, when the machine is in operation, the idle axles are relieved of all or part of their load to increase the axle load of the drive axles.

In addition, it is known tG.B. Specification 1288283) that a track tamping, levelling and lining machine may be provided with several on-track undercarriages arranged one behind the other longitudinally of the machine to achieve adaptation to different working conditions. One of these on-track undercarriages may be temporarily brought into engagement with and disengaged from the track. In this way, the interval between the on-track undercarriages in the longitudinal direction of the track may be maintained in accordance with particular requirements.Thus, the fairly considerable flexural stressing which the rails undergo when the track is being lifted and laterally aligned by means of the correcting units arranged between the axles - if the distance between axles is excessive -- may be reduced in this way, whereas when the machine is in transit and travelling and much higher speeds its ability to negotiate curves in the track and its stability may be improved by a relatively short interval between axles.

The object of the present invention is to provide a machine of the type described at the beginning which is capable of travelling along different tracks having different permitted limit axle loads.

According to the invention, this object is achieved in that, in the travelling on-track machine described at the beginning, the undercarriage optionally supportable on the track is mounted on a shaft-like additional chassis pivotally connected to the chassis of the machine, the adjustment drive optionally connected to the control system being pivotally connected at one end to the additional chassis and at its other end to the chassis. A machine constructed in accordance with the invention provides at relatively low cost an effective and robust axle-load-distributing arrangement which is even capable very easily of travelling along tracks with different permitted axle loads and which may even be subsequently fitted without difficulty to various, already proven types of machine.Another particular advantage lies in the fact that, by virtue of the pivotal connection of the additional chassis, the ability even of long and heavy track maintenance machines to negotiate curves is not impaired in any way despite the increase in the length of the machine which this pivotal connection involves.

Another advantage of the invention lies in the fact that the chassis of the machine does not have to be structurally modified to any significant extent so that the space required for installing and using track or ballast treating or measuring units also remains fully available. One particular advantage lies in the application of the invention to a trackmeasuring car because, by virtue of the extension provided by the additional chassis, the measuring wheels arranged below the chassis of the measuring car and connected to the undercarriages of the measuring car for measuring various track parameters may continue to be used in the proven manner without the least restriction.

The term "shaft-like" herein indicates a constructional arrangement resembling the draw shaft or pole of a horse-drawn cart or similar vehicle.

The invention may also be used with particular advantage in conjunction with a ballast cleaning machine. In this case, the use of at least one additional chassis according to the invention at that end of the machine which is situated nearer the sieve and which is therefore more heavily loaded makes it possible fully to utilise the capacity of the sieve, even under working conditions of varying difficulty, such as for example fairly high density and hence greater weight of the ballast, moisture or the like, without exceeding the maximum permitted axle load.

According to another aspect of the invention, the pivot connecting the shaft-like additional chassis to the chassis of the machine is situated in the immediate vicinity of an undercarriage of the machine and the adjustment drive is pivotally connected at the end of the chassis to supporting frames projecting longitudinally of the machine.

Where the machine is relatively short in terms of its overall length, this embodiment is characterised by good curve-negotiating ability, the supporting frames providing for simple subsequent fitting to machines already in service.

In another embodiment of the invention, the adjustment drive consists of a hydraulic pistonand-cylinder assembly, the piston preferably being pivotally connected to the shaft-like additional chassis and the cylinder to the chassis of the machine. This embodiment is distinguished by its practicality and robustness, particularly in view of the frequently varying loads of the additional chassis.

Another embodiment of the invention is characterised in that a shaft-like additional chassis with an undercarriage optionally supportable on the track is arranged at either end of the machine, the adjustment drives being activatable independently of one another through the control system for vertically adjusting the particular additional chassis with the corresponding undercarriage as required. This extension of the undercarriage at both ends affords numerous possibilities for distributing the weight of the machine over the undercarriages present, in addition to which in cases where the machine has different driving axle loads by reason of its construction these loads may be lightened to just below the limit load in order to obtain the greatest possible tractive power.

In one particularly advantageous embodiment of the invention, a distance recorder which records the particular difference in the vertical spring deflection in dependence upon the activation of the adjustment drives and which is designed to supply distance-related electrical measured values is associated with the optionally supportable undercarriage arranged on the shaft-like additional chassis and also equipped with spring assemblies.

In view in particular of the robust use of the additional chassis, this embodiment of the invention provides a reliable and accurate, inexpensive arrangement for measuring the particular axle load of the undercarriages optionally supportable on the track. In particular, the machine is immediately able to travel along sections of track having different characteristics without the slightest loss of time through re rigging work or the like after activation of the adjustment drives connecting the additional chassis to the associated supporting frames.

According to another aspect of the invention, the distance recorder consists of a rotary potentiometer and is fixed to an undercarriage frame of the optionally supportable undercarriage, its rotatable regulating element being connected by a cable to the axle bearing box of the undercarriage. This special construction is extremely simple and hence very reliable despite the robust application. the rotation of the regulating element in proportion to the spring travel under load enabling the axle load of the undercarriages mounted on the additional chassis to be accurately determined.

Another advantageous embodiment of the invention is characterised in that the control system connected by control lines to the adjustment drives for automatically regulating the limit axle loads is connected to the distance recorders by electrical control lines, the adjustment drives being designed for activation through the control system in dependence upon the consistency between a load component recorded by the distance recorders and a difference -- feedable into the control system between the particular axle load of the machine under carriage and the limit axle load.By virtue of the automatic adaptation of the axle loads to the permitted axle loads which this embodiment allows, the machine operator is completely relieved of monitoring work and travelling along sections of track having different track characteristics does not involve any problems even for the heaviest track maintenance machines. A characteristic quantity that is easy to form is available through the limit axle load feedable by the machine operator into the control system and the difference subsequently formed between that load and the known axle load of the machine undercarriages.This characteristic quantity represents the minimum value of any necessary loading of the undercarriages mounted on the two additional chassis by means of the adjustment drives in order to lighten the load of the machine undercarriages to below the permitted axle load of the track along which the machine is travelling. The adjustment drives which press the shaft-like additional chassis together with the undercarriages on to the track are automatically activated by the control system until the electrical measured-value signals formed by the distance recorders are identical with the above-mentioned characteristic quantity.

According to another aspect of the invention, a shaft-like additional chassis with an optionally supportable undercarriage is pivotally connected to either end of the chassis of a track measuring vehicle. This embodiment of the invention affords the particular advantage that another interesting comparative measurement of various track parameters is available through the possibility of differently loading the machine undercarriages included in the measuring system - by loading the two additional chassis activated by the adjustment drives to different extents. In addition, the undercarriages of the track-measuring car which are included in the measuring system remain uninfluenced and, accordingly, may continue to be used in the proven manner as a reference basis for various track measurements.

Finally, another embodiment of the invention is characterised in that a shaft-like additional chassis with an optionally supportable undercarriage is provided at either end of a ballast cleaning machine and pivotally connected to the chassis in the region of a bogie-type undercarriage of the ballast cleaning machine. With a ballast cleaning machine constructed in this way, it is possible with advantage to use particularly highperformance but heavy track maintenance machines of this type also along various sections of track with different permanent-way characteristics without exceeding the particular maximum permitted axle load. Accordingly, there is no need to bring in or prepare a smaller ballast cleaning machine for branch lines with lighter permanent-way characteristics so that this embodiment of the invention is distinguished by its particularly high economy.On the other hand, however, it is also possible in the case of a heavy permanent way for the optionally supportable undercarriages according to the invention to be supported on the track solely for in-transit runs in order to increase the speed of travel and to reduce the dynamic forces acting on the track. By contrast, when the ballast cleaning machine is in operation, the additional chassis with their undercarriages may be additionally relieved of load or completely lifted off the track to increase the tractive power of the driven machine undercarriages.

Two examples of embodiment of the invention are described in detail in the following with reference to the accompanying drawings, wherein: Figure 1 is a side elevation of a travelling ontrack machine in the form of a track-measuring car according to the invention.

Figure 2 is a plan view of the chassis and the additional chassis of the track-measuring car together with the undercarriages.

Figure 3 is a side elevation on a larger scale of a modified undercarriage mounted on the additional chassis.

Figure 4 is a side elevation of another embodiment of a travelling on-track machine according to the invention in the form of a ballast cleaning machine shown in diagrammatically simplified form.

The track-measuring car 1 shown in Figure 1 consists of a chassis 5 which is designed to travel along a track 4 on sprung undercarriages 2, 3 and which is extended at either end by supporting frames 6 projecting longitudinally of the machine, and of a compartment of cabin 7 arranged on the chassis. At either end of the chassis 5, an additional chassis 9 which is designed for alternate vertical displacement by an adjustment drive 8 and which will be described in more detail hereinafter is connected to the track-measuring car 1 through a pivot 10 in the form of a universal joint arranged in the vicinity of the undercarriages 2, 3 in the form of single-axle axxemblies.The adjustment drives 8 which consist of a hydraulic piston-and-cylinder assembly are connected at one end by their cylinders 11 to the supporting frames 6 and at their other end by their pistons 1 2 to the additional chassis 9 in such a way that they are able to pivot in any direction. Pressure medium is designed to be introduced and removed through control lines 1 3 to activate the piston 12 at either end. At the end of the additional chassis 9, there is an idle axle designed to be supported on the track 4 as required by a standard undercarriage 14 sprung by a spring assembly.A distance recorder 1 5 in the form of a rotary potentiometer for measuring the vertical spring deflection of the spring assembly which changes under load is fixed to the undercarriage 14, being connected to the axle bearing box by a mechanism which will be described in detail hereinafter. An electrical control line 1 6 connects the distance recorder 1 5 to a control system 1 7 which is additionally connected to the hydraulic control lines 13 leading to the adjustment drives 8 and which, for each additional chassis 9, comprises a digital measured-value input unit for the required load of the optionally supportable undercarriages 14.

Further hydraulic control lines establish a connection to a pressure-medium supply unit driven by a propulsion drive 18. Of the undercarriages 2,3 fixedly connected to the chassis 5, the undercarriage 2 driven by the propuision drive 1 8 is loaded more heavily than the other undercarriage 3 in the form of an idle axle. Paired measuring wheels 1 9 designed for travel along the track and for vertical adjustment by compressed-air cylinders are pivotally connected both to the undercarriages 2, 3 and also to the chassis 5 by longitudinal guide rods, being coupled to mechanisms for recording various parameters of the track. These various track parameters are delivered in the form of electrical signals to various measuring and recording units accommodated in the compartment 7.

The chassis 5 shown in plan in Figure 2 consists of two longitudinal girders 21 which are joined together by two cross girders 20 and to the ends of each of which a supporting frame 6 connected to an adjustment drive 8 and projecting longitudinally of the machine is fixed, forming an extension of the chassis 5. The opposite end of each adjustment drive 8 is pivotally connected over the flanged wheel of the optionally supportable undercarriage 1 4 to an undercarriage support frame 22 of the additional chassis 9.

Through a coupling system 23 in the form of a shaft arrangement, the undercarriage support frame 22 is both vertically adjustable about a horizontal shaft extending transversely of the longitudinal axis of the machine and also pivotal about a vertical shaft at the pivot 10 for negotiating curves in the track.

Compared with the undercarriage 1 4 shown in Figure 1, and undercarriage 24 shown on a larger scale in Figure 3, which is supported on the track 4 and loaded by the adjustment drive 8, is specially constructed and consists of a spring assembly 25 and an axle bearing box 26 in which a flanged wheel is mounted and on which a spring yoke 27, a flat-bar suspension 28 and an undercarriage frame 29 of the additional chassis 9 are supported through the spring assembly 25. A shock absorber 30 connected to the axle bearing box 26 is used for stabilising oscillation.The distance recorder 1 5 in the form of a rotary potentiometer is fixed laterally to the underneath of the frame 29, its rotatably mounted regulating element 31 being connected by a cable 32 guided around a guide roller 33 fixed to the undercarriage frame 29-to the axle bearing box 26. When the undercarriage frame 29 together with the distance recorder 1 5 and the additional chassis 9 is lowered (chain-line position) in the event of loading by the adjustment drives 8 situated laterally opposite one another in the axial direction, the regulating element 31 is turned in the arrowed direction by an amount proportional to the compression of the springs of the spring assembly 25.As a result, an electrical voltage proportional to the load applied by the adjustment drives 8 is given off to the control line 1 6 in the distance recorder 1 5.

The other embodiment of the invention shown in Figure 4 consists of a heavy ballast cleaning machine 34 designed to travel along a track 37 through a chassis 35 in conjunction with two bogie-type undercarriages 36 arranged at either end thereof. As in the other embodiment shown in Figure 2, two supporting frames 38 situated opposite one another transversely of the longitudinal axis of the machine are provided at either end of the chassis 35, forming extensions thereof and being connected through adjustment drives 39 to vertically and laterally pivotal additional chassis 40. These additional chassis 40 are pivotally connected to the chassis 35 by a universal joint in the vicinity of the bogie-type undercarriages 36. The distance recorders 42 fixed to the undercarriages 41 supported on the track 37 are connected by electrical control lines to an indicating unit 43.The adjustment drives 39 are connected for optional activation to a control unit 44 by hydraulic control lines.

The mode of operation of the machine 1 (34) constructed in accordance with the invention will now be described with reference to Figs. 1 to 4.

The track-measuring car 1 with its paired measuring wheels 1 9 running along the track 4 is a heavy measuring and inspection vehicle which continuously surveys the track for any errors in its geometry under load conditions similar to those prevailing during the passage of a train and electronically records any errors detected.

Normally, the heavy weight of the machine is adapted to the most heavily loaded main tracks because, in most cases, they make up the greater part of all railway networks and, in view of their considerable economic significance, also have to be monitored and surveyed more frequently.

However, by means of the construction according to the invention, the heavy track-measuring car 1 may also be used for inspecting and surveying branch lines, where the permitted limit axle load is lower by comparison with the axle load, in the usual way. If for example the less heavily loaded undercarriage 3 of the track-measuring car 1 still just falls below the permitted limit axle load, it is merely necessary to take some of the load off the more heavily loaded driving undercarriage 2. To this end, the machine operator feeds that quantity by which the axle load of the undercarriage 2 is too high into the corresponding measured-value input unit of the control system 1 7.Thereafter only the additional chassis 9 shown on the lefthand side of the drawing is lowered on to the track 4 and the corresponding adjustment drives 8 automatically receive pressure until the distance recorder 1 5 of the loaded undercarriage 14 gives off a measured value which corresponds to the quantity fed in. Thus the axle load of the two undercarriages 2, 3 is the same and below the permitted limit axle load, as indicated by the arrows. The axle load of the loaded undercarriage 14 connected to the additional chassis 9, which only corresponds to the difference between the axle load of the undercarriage 2 and the limit axle load, is correspondingly lower, as indicated by an arrow. After this automatic lightening of the axle loads to the permitted limit axle load, the branch line is surveyed and inspected without any interference.When the track-measuring car arrives at another branch line with an even lower limit axle load, the axle load of the machine undercarriages 2, 3 may be even further reduced by feeding the corresponding quantity into the control system 1 7 to increase the load of the undercarriage 14 already supported on the track and additionally lowering and loading the other, opposite undercarriage 14. Accordingly, the trackmeasuring car is even able to travel freely along sections of track having different characteristics without any need for modifications to be made.

With the construction according to the invention, the high-performance and therefore heavy ballast cleaning machine 34 may also be used on branch lines where the permitted limit axle loads are relatively low. To this end, the machine operator has to lower the additional chassis 40 with the undercarriages 41 on to the track 37 by means of the control system 44, i.e. by activation of the adjustment drives 39, until the necessary lightening of the load of the bogie-type undercarriages 36 to below the permitted limit axle load is indicated on the indicating unit 43 connected to the distance recorders 42. The heavy ballast cleaning machine 34 thus supported on six axles may then be used for cleaning the ballast bed in the usual way without dangerous overloading of the track 37.

The embodiments described in the foregoing and illustrated in the accompanying drawings do not limit the invention in any way because the invention lends itself to modification in many ways. For example, bridge-like cross girders joining together the two ends of the - in particular -- extendable longitudinal girders of the chassis may be provided instead of projecting supporting frames. However, the additional chassis may also be pivotally connected to a travelling on-track machine in the region of the couplings, in which case the optionally lowerable single-axle undercarriage may even be replaced by a bogie-type undercarriage for supporting the chassis on the track.

Claims (10)

1. A travelling on-track machine, more particularly a track-measuring or track maintenance machine, for surveying or working on a railway track comprising a chassis guided on the track by an on-track undercarriage arrangement comprising several undercarriages and further comprising at least one undercarriage optionally supportable on the track through an adjustment drive and, optionally, a control system for activating the adjustment drive as required to reduce or increase the respective undercarriage axle loads, characterised in that the undercarriage optionally supportable on the track is mounted on a shaft-like additional chassis pivotally connected to the chassis of the machine the adjustment drive optionally connected to the control system being pivotally connected at one end to the additional chassis and at its other end to the chassis.

2. A machine as claimed in Claim 1, characterised in that the pivot (10) connecting the shaft-like additional chassis to the chassis of the machine is situated in the immediate vicinity of an undercarriage of the machine and the adjustment drive is pivotally connected at the end of the chassis to supporting frames projecting longitudinally of the machine.

3. A machine as claimed in Claim 1 or 2, characterised in that the adjustment drive consists of a hydraulic piston-and-cylinder assembly, the piston preferably being pivotally connected to the shaft-like additional chassis and the cylinder to the chassis of the machine.

4. A machine as claimed in any of Claims 1 to 3, characterised in that a shaft-like additional chassis with an undercarriage optionally supportable on the track is arranged at either end of the machine, the adjustment drives being activatable independently of one another through the control system for vertically adjusting the particular additional chassis with the corresponding undercarriage as required.

5. A machine as claimed in any of Claims 1 to 4, characterised in that a distance recorder which records the particular difference in the vertical spring deflection in dependence upon the activation of the adjustment drives and which is designed to supply distance-related electrical measured values is associated with the optionally supportable undercarriage arranged on the shaftlike additional chassis and also equipped with spring assemblies.

6. A machine as claimed in Claim 5, characterised in that the distance recorder consists of a rotary potentiometer and is fixed to an undercarriage frame of the optionally supportable undercarriage, its rotatable regulating element being connected by a cable to the axle bearing box f the undercarriage.

7. A machine as claimed in any of Claims 1 to 6, characterised in that the control system connected by control lines to the adjustment drives for automatically regulating the limit axle loads is connected to the distance recorders by electrical control lines, the adjustment drives being designed for activation through the control system in dependence upon the consistency between a load component recorded by the distance recorders and a difference -- feedable into the control system -- between the particular axle load of the machine undercarriage and the limit axle load.

8. A machine as claimed in any of Claims 1 to 7, characterised in that a shaft-like additional chassis with an optionally supportable undercarriage is pivotally connected to either end of the chassis of a track-measuring car.

9. A machine as claimed in any of Claims 1 to 7, characterised in that a shaft-like additional chassis with an optionally supportable undercarriage is provided at either end of a ballast cleaning machine and pivotally connected to the chassis in the region of a bogie-type undercarriage of the ballast cleaning machine.

10. An on-track machine, substantially as herein described with reference to figures 1 to 3 or Figure 4 of the accompanying drawings.