GB2267305A

GB2267305A - A track maintenance machine with a vertically adjustable track lifting unit.

Info

Publication number: GB2267305A
Application number: GB9310691A
Authority: GB
Inventors: Josef Theurer; Herbert Woergoetter
Original assignee: Franz Plasser Bahnbaumaschinen Industrie GmbH
Current assignee: Franz Plasser Bahnbaumaschinen Industrie GmbH
Priority date: 1992-05-26
Filing date: 1993-05-24
Publication date: 1993-12-01
Anticipated expiration: 2013-05-24
Also published as: AT400862B; FR2691725B1; GB9310691D0; ATA108792A; FR2691725A1; DE9307243U1; GB2267305B

Abstract

A track lifting unit 13, connected to the frame 3 of a track maintenance machine 1, is vertically adjustable by means of drives 19. The track lifting unit 13 has lifting tools 20, connected to a carrier frame 18, which can be engaged with rails 24 by drives 23. An eccentric drive 26 having an axis of rotation extending in the longitudinal direction of the machine 1 is connected to the carrier frame 18 by means of a horizontal swinging arm 28, a vertical arm 29 and a further horizontal arm 30 so as to oscillate the carrier frame 18 horizontally for ballast bed compacting. The length of the swinging arm 28 can be adjusted to effect lateral displacement of the carrier frame 18 for lateral track alignment purposes. A ballast cleaning machine incorporating such a track lifting unit is also disclosed. <IMAGE>

Description

A TRACK MAINTENANCE MACHINE WITH A VERTICALLY ADJUSTABLE TRACK LIFTING UNIT The present invention relates to a railway track maintenance machine with a machine frame supported on on-track undercarriages and a track lifting unit connected to the machine frame and vertically adjustable by means of vertical drives, the track lifting unit having a carrier frame and also lifting tools which are connected to the carrier frame and may be placed against rails by means of drives for the purpose of positive locking union with a track.

A track maintenance machine of this kind is already known through US 3 685,589 B, this being designed as a ballast bed cleaning machine having an elongated machine frame mounted at each end on on-track undercarriages. A vertically and laterally adjustable excavating chain is situated on the machine frame, arranged approximately centrally between the undercarriages, for picking up and conveying fouled ballast upwards into a screening unit.

Two mutually independent conveyor belts running to respective ends of the machine, are arranged for carrying away the spoil separated by the screening unit. The introduction of the cleaned ballast from the screening unit is performed by a distributing conveyor belt, the discharge area of which is situated immediately behind the excavating chain in the operating direction of the machine.

In the area of the ballast bed gap or of the cutter bar of the excavating chain, the track is lifted with the aid of a track lifting unit which is vertically adjustable by means of vertical drives and is connected to.the machine frame.

The machine has a carrier frame and also lifting tools which are connected to the carrier frame and may be placed against rails by means of drives for the purpose of positive locking union with a track. Located immediately behind the ballast discharge position is a second track lifting unit of the same kind with which the track may be lifted far enough to enable a grading and consolidating device to be used in the area between the discharged ballast and the sleepers. The track is laid on the ballast consolidated with the grading and consolidating device, and a chute is provided in the rear end region of the screening unit to fill the sleeper cribs. By means of this chute a part of the cleaned ballast may be discharged between the sleepers directly from the screening unit.A certain degree of consolidation of the cleaned ballast bed may be accomplished with this known cleaning machine, but relatively high lifting of the track and also a fairly large number of operating units are required when this type of machine is used.

Consolidating the ballast bed of a tack using a socalled stabiliser is also known. A machine of this type which is continuously advancable is described in US 4,064,807 B, for example, in which the track is lifted approximately centrally between two widely spaced under carriages of a machine frame. By means of a plough arrangement, arranged in this area, the exposed surface of ballast is graded. The track panel is then relaid on the, now levelled, ballast bed. By means of a consolidating device linked to the machine frame in front of the rear under carriage or a stabilising unit, the track is then set vibrating horizontally and is acted upon with a vertically applied load in order to consolidate the ballast bed. This effects settlement normally caused by train traffic. For this purpose the stabilising unit has flanged rollers, connected to a carrier frame.The rollers may be brought into positive-locking engagement with the rails of the track by means of the drives. The stabilising unit also has vertical drives for the lowering of the unit, which lowering is monitored with the aid of a reference system.

The vibrations are generated by means of eccentric weights arranged on the carrier frame and connected to a drive.

The carrier frame is additionally fitted with alignment cylinders, positioned obliquely and provided for the lateral alignment of the unit.

A further machine for ballast bed cleaning which is known according to US 4,846,282 B has a bridge-shaped machine frame supported at each end on undercarriages and an excavating chain and a screening unit which may be supplied by the excavating chain with excavated bedding ballast.

The track panel is lifted in the area of the excavation position by a track lifting unit. The cleaned ballast is reintroduced into the track by way of various devices.

Located immediately in front of the rear undercarriage, in the operating direction, are alignment grippers which serve to geometrically align a track correctly corresponding to the track position previously existing before the track maintenance work occurred. Due to the rather small distance of the alignment grippers away from the adjacent undercarriage, their effectiveness is severely limited.

An object of the present invention is to provide a track maintenance machine with which a known track lifting unit, provided for lifting the track, may also be employed for consolidating the ballast bed or for stabilising the track position, and involves only a small amount of extra constructional expense.

To this end a track maintenance machine of the type described in the introduction is provided in which the carrier frame is connected by means of a swinging arm, extending substantially perpendicularly to the longitudinal direction of the machine, to an eccentric drive secured to the machine frame and having an axis of rotation extending substantially in the longitudinal direction of the machine.

Connecting the track lifting unit in this way to an eccentric drive enables the lifting of the track or correction of the track position to be combined advantageously both functionally and constructionally with stabilisation of the track position. This stabilisation of the track position is especially advantageous with a ballast bed which has very recently been completely remade by the discharge of ballast. Such a ballast bed will have a very inhomogeneous packing density. Since, firstly the ballast distribution immediately beneath the sleepers is very uneven, and secondly errors in initial vertical position of the replaced track are inevitable as a result of the uneven discharge of ballast, vibration of the track in combination with a static load which may be applied by the vertical drives has a very advantageous effect with respect to an improved track position. The use of a track maintenance machine according to the invention will accordingly result in a track along which trains will be able to travel at a higher speed than was previously possible.

According to the preferred modification of claim 2, a flexible arrangement of the lever arms enables the track lifting unit to be raised or disengaged without difficulty for the purpose of machine transit. The unit can also be vertically adjusted relative to the machine frame without interruption in the vibration transmission. This may be necessary if the height of the track position to be established varies.

The further features of claims 3 and 4 effect the optimum conversion of the rotational movement of the eccentric drive into a reciprocating oscillation of the carrier frame of the track lifting unit.

If a vertical measurement pick-up and a vertical reference system are associated with the track lifting unit, the desired vertical position of the track or levelling of the track can be precisely monitored. The modification according to claim 6 also enables the track position to be simultaneously corrected in the transverse direction, so as to produce a track which is substantially aligned in the transverse direction. The modification according to claim 7 is particularly preferred in this respect. In this modification an exceedingly simple construction and the optimum space-saving arrangement of the alignment drive is provided.

The arrangement according to claim 8 advantageously provides for an immediate response to and adjustment of track high points detected in the course of monitoring the vertical position of the track. The degree of ballast consolidation and with it the amount of lowering can be influenced by carrying the oscillation frequency and/or the applied load.

In a further modification of the invention, a ballast discharge position for depositing ballast on to a formation is situated immediately in front of the track lifting unit. Because of this arrangement the ballast may be set vibrating in the most advantageous manner immediately after its discharge, so as to produce the best result with respect to pre-consolidation.

The ballast bed cleaning machine set forth in claim 10 and equipped in accordance with the invention enables a relatively stable track to be created immediately after ballast cleaning without the need for employing a track stabiliser or a tamping machine. The track permits comparatively high traffic speed. Thus the best possible use can be made of track possession periods which are available for the operation of the machine. Retrofitting a cleaning machine already in service with an eccentric drive according to the invention for setting the track lifting unit vibrating can be accomplished quickly and without any problem at all because of the particularly simple construction disclosed.

In order that the invention may be more readily understood reference will now be made by way of example to the embodiment illustrated in the accompanying figures in which: Figure 1 shows a side view of a track maintenance machine with a track lifting unit designed according to the invention, Figure 2 shows an enlarged view of the track lifting unit according to Figure 1, and Figure 3 shows an enlarged view of the track lifting unit in the longitudinal direction of the machine, in the direction of arrow III in Figure 2.

Figure 1 shows a track maintenance machine designed as a ballast bed cleaning machine 1 which has an elongated machine frame 3 mounted at each end on on-track undercarriages 2 and which can travel on a track 5 in an operating direction indicated by an arrow 4. Situated approximately centrally between the two undercarriages 2 is an endless excavating chain 6. This excavating chain passes through below the level of the track 5 during use, and is connected for lateral and vertical adjustment relative to the machine frame 3. The excavating chain discharges the fouled bedding ballast picked up from the track 5 at an excavation position 7 on a conveyor belt 8 which conveys the ballast to a screening unit 9, represented only as an outline. In the screening unit 9 spoil is screened out and loaded for further transportation.The portion of the ballast which has now been cleaned passes by way of a conveyor means 10 to distributing conveyor belts 11 which reintroduce the ballast onto the track 5 at a location situated behind the excavation position 7 in the operation direction. A first track lifting unit 12 is vertically adjustably connected to the machine frame 3 in the region of the excavating chain 6. Immediately behind the distributing conveyor belts 11, in the operating direction, there is arranged a further track lifting unit which will be described in more detail with the aid of Figures 2 and 3. A central power plant 14 supplies a machine transit drive 15 and also all the working units of the machine 1. The machine is further provided with a driver's cab 16 and an operator's cab 17.

The track lifting unit is shown in detail in Figures 2 and 3. It has a T-shaped carrier frame 18, extending in the longitudinal direction of the machine, which is linked to the machine frame 3 at its rear end, in the operating direction. The front end of the carrier frame 18 is similarly connected in an articulated manner by way of two vertical drives 19 to the machine frame 3, by means of which the carrier frame 18 is vertically adjustable in relation to the machine frame. Arranged on the carrier frame 18 are lifting tools 20 consisting of flanged rollers 21 and lifting plates 22. These may be connected to or placed against the rails 24 of the track 5 in a positive locking manner.

Secured to a transverse beam 25 of the machine frame 3 in the region of the articulated attachment of the vertical drives 19 is an eccentric drive 26 with an axis of rotation 27 extending in the longitudinal direction of the machine. The eccentric drive 26 has a swinging arm 28 which extends perpendicularly to the longitudinal direction of the machine and is arranged approximately horizontally.

One end of the swinging arm 28 is connected to the eccentric drive, and its other end is rotatably connected to the centre of a substantially vertical lever arm 29.

One purpose of the swinging arm is to oscillate longitudinally so as to transfer vibratory movement produced by the eccentric drive 26 to the vertical lever arm 29. The upper end of the vertical lever arm 29 is pivotally linked to the machine frame 3, while its lower, free end is connected in an articulated manner to one end of a further lever arm 30 which is arranged approximately horizontally. The other end of the lever arm 30 is in turn pivotally linked to the underside of the carrier frame 18.

The swinging arm 28 is designed as an alignment drive 31, the length of which is variable. By means of swinging arm 28 the track lifting unit can be translated in the transverse direction of the machine relative to the machine frame 3. This enables the lateral excursion, necessary when the machine travels round a track curve, to be effected, or to enable lateral track position corrections to be made.

In the region of the vertical drives 19, respective vertical measurement pick-ups 32 or distance pick-ups, are secured to the hydraulic cylinder constituting the vertical drive. The pick-ups 32 are operatively connected to the track lifting unit and are associated with a vertical reference system 33 which uses the machine frame 3, between the on-track undercarriages 2, as the references basis for the vertical position of the track. The vertical drives 19 are further provided with servo valves 34 which together with the vertical measurement pick-ups 32 and the eccentric drive 26 are connected to an automatic control means 35 located in the operators cab 17.This control means is designed for controlling the oscillation frequency of the eccentric drive 26 and/or the static load applied to the track 5 by the vertical drive 19 in dependence on the vertical deviations determined by the vertical measurement pick-ups 32 or to adjust their setting in order to achieve the optimum track position.

As already mentioned, the track lifting unit is arranged in the operating direction behind the distributing conveyor belts 11 which introduce ballast at a discharge position on to the formation beneath the track 5. The two distributing conveyor belts 11 are provided above respective rails 24 of the track 5, these being covered in the discharge region of the ballast by respective rail tunnels 36 arranged on the track lifting unit . Arranged on either side of the rail tunnels 36 are vertical baffle or deflection plates 37, situated opposite the discharge end of the discharge conveyor belts 11. These plates 37 are respectively adjustable about vertical axes 38 by means of a drive 39. Angling of the plates to the longitudinal direction of the track will direct the discharged ballast more or less to one side or the other side of the rail 24 as required.

During operation of the cleaning machine 1, the track lifting unit primarily serves to hold the track 5 in the desired position while the ballast is discharged. In parallel therewith there is the option of vibrating the track horizontally in the region of the lifting tools 20 by means of the eccentric drive 26. This will achieve the consolidation of the ballast immediately after its discharge from the conveyor belt 11. If, for example, excessive qualities of ballast cause an undesired high point in the track, the track 5 can be urged downwards more strongly in a controlled manner for a short period by appropriate actuation of the vertical drives 19 and/or by variation of the rotational speed of the eccentric drive 26, until the desired vertical position is reached. In order to increase the overall consolidating effect it is also possible to apply a vertically applied load by means of the vertical drives 19 continuously in parallel with the horizontal transverse oscillations of the track. Obviously it is also possible to switch off the eccentric drive 26 without adversely affecting the normal lifting function of the track lifting unit.

Claims

1. A railway track maintenance machine with a machine frame support on on-track undercarriages and a track lifting unit connected to the machine frame and vertically adjustable by means of vertical drives, the track lifting unit having a carrier frame and also lifting tools which are connected to the carrier frame and may be placed against rails by means of drives for the purpose of positive locking union with a track, wherein the carrier frame is connected by means of a swinging arm, extending substantially perpendicularly to the longitudinal direction of the machine, to an eccentric drive secured to the machine frame and having an axis of rotation extending substantially in the longitudinal direction of the machine.

2. A machine according to claim 1 wherein the swinging arm is linked to a lever arm which is secured in an articulated manner to the machine frame, the opposite lower end of the lever arm being connected to a further lever arm linked to the carrier frame.

3. A machine according to claim 2 wherein the lever arm secured to the machine frame is arranged approximately vertically while the further lever arm linked to the carrier frame extends approximately horizontally and approximately perpendicularly to the longitudinal direction of the machine.

4. A machine according to any one of the preceding claims wherein the swinging arm connected to the eccentric drive is designed so as to extend approximately horizontally.

5. A machine according to any one of the preceding claims wherein a vertical measurement pick-up and a vertical reference system are associated with the track lifting units.

6. A machine according to any one of the preceding claims wherein at least one alignment drive extending substantially perpendicularly to the longitudinal direction of the machine is provided between the carrier frame and the machine frame.

7. A machine according to any one of the preceding claims wherein the swinging arm is designed as an alignment drive the length of which is variable.

8. A machine according to any one of the preceding claims wherein servo valves are associated with the vertical drives, and the eccentric drive and also the vertical measurement pick-up are connected to a control means for automatically controlling the oscillation frequency and/or the static load applied by means of the vertical drives in dependence on the vertical deviations of the track from a required position.

9. A machine according to any one of the preceding claims wherein a ballast discharge position is situated immediately in front of the track lifting unit (13) for introducing ballast on to a formation.

10. A ballast cleaning machine which is mobile on a railway track and has an endless excavating chain passable through below the level of the track, a conveyor belt for conveying the fouled ballast away to a screening unit and a conveyor means for conveying the ballast cleaned in the screening unit to a distributing conveyor belt for reintroduction into the track, in addition to a first track lifting unit arranged on the machine frame in the region of the excavating chain, a second track lifting unit is provided at a distance away from the first track lifting unit in the longitudinal direction of the track and arranged in the discharge region of the distributing conveyor belt, the second track lifting unit being connected to the eccentric drive and having at its end region facing the distributing conveyor belt a respective rail tunnel for each rail of the track and vertical baffle or deflection plates arranged on either side of the rail tunnel which are adjustable at an angle to the longitudinal direction of the track by means of a drive.

11. A railway track maintenance machine according to any one of claims 1 to 9 including a ballast bed cleaning machine according to claim 10.

12. A railway track maintenance machine constructed substantially as hereinbefore described with reference to Figures 1, 2 and 3.

13. A ballast bed cleaning machine constructed substantially as hereinbefore described with reference to Figures 1, 2 and 3.