EP4176132A1

EP4176132A1 - Method and machine comprising a tamping assembly

Info

Publication number: EP4176132A1
Application number: EP21731089.5A
Authority: EP
Inventors: Josef HOFSTÄTTER
Original assignee: Plasser und Theurer Export Von Bahnbaumaschinen GmbH
Current assignee: Plasser und Theurer Export Von Bahnbaumaschinen GmbH
Priority date: 2020-07-03
Filing date: 2021-06-02
Publication date: 2023-05-10
Also published as: WO2022002521A1; AT524005A1

Abstract

The invention relates to a method and a machine comprising a tamping assembly for tamping sleepers (4), mounted on a ballast bed (2), of a track (3) by means of a tamping assembly (7) which is intended for simultaneously tamping a plurality of sleepers positioned directly one behind the other and comprises a plurality of tamping units (14) that are arranged directly one behind the other in a working direction (26), are height-adjustable independently of one another, and are each intended for tamping a particular sleeper (4), wherein: in a tamping cycle, firstly a first group of tamping units (14) that are not arranged directly one behind the other is lowered into the ballast bed (2), fed laterally and raised again; a second group of tamping units (14) that are not arranged directly one behind the other is preferably lowered into the ballast bed, fed laterally and raised again; and, before the start of the next tamping cycle, the tamping assembly (7) is moved further in the working direction (26). This prevents two tamping tools (18) from operating simultaneously on the same ballast grains in close proximity.

Description

description

Process and machine with a tamping unit

Technical area

The invention relates to a method for tamping under sleepers stored in a ballast bed by means of a tamping unit for simultaneous tamping of several sleepers positioned immediately one behind the other, with several tamping units arranged in a working direction directly behind one another and independently height-adjustable for tamping a sleeper. The invention also relates to a machine for carrying out the method.

State of the art

[02] To restore or maintain a given track position, tracks with ballast bedding are regularly processed by means of a tamping machine. The tamping machine drives along the track and uses a lifting / straightening unit to raise the track grid, which is made up of sleepers and rails, to a target level. The new track position is fixed by tamping under the sleepers using a tamping unit. The tamping unit comprises tamping tools with tamping tines which, when subjected to a tamping process, dip into the ballast bed and are placed next to each other. The ballast is compacted below the respective threshold.

[03] In particular, stretch tamping machines use tamping units for tamping several sleepers at the same time. The high processing speed achieved in this way enables a track to be worked through in short breaks. Modern tamping machines are also characterized by low wear effects on both the tamping unit and the ballast.

From AT 513034 A1 a generic machine with at least two tamping units arranged one behind the other is known. Each tamping unit is height-adjustable in a common unit carrier. A tamping cycle begins with the common lowering of the tamping units. This joint lowering of adjoining tamping units for tamping under sleepers that are adjacent in the longitudinal direction of the machine takes place with a time delay. This in particular facilitates the immersion of immediately adjacent tamping tines that immerse into a common threshold compartment.

Presentation of the invention

[05] The invention is based on the object of improving a method of the type mentioned at the beginning in such a way that particularly gentle processing of the ballast bed is possible. In addition, a correspondingly improved machine for carrying out the method is to be specified.

[06] According to the invention, these objects are achieved by the features of the independent claims 1 and 7. Dependent claims specify advantageous embodiments of the invention.

In a tamping cycle, a first group of tamping units not arranged directly one behind the other is first lowered into the ballast bed, provided and raised again, with a second group of tamping units not arranged directly behind one another preferably being lowered into the ballast bed, provided and raised again whereby the tamping unit is moved further in the working direction before the start of the next tamping cycle. The method relates to a row tamping unit, which is usually used for tamping several sleepers directly behind one another at the same time. In contrast to this conventional mode of operation, when the tamping unit is operated according to the invention, there is no simultaneous tamping under the sleepers located below the unit. Specifically, a stuffing cycle modified in this way is divided into a sequence of stuffing processes with grouped stuffing units. The respective stuffing cycle is concluded with a forward movement of the stuffing unit in the working direction in order to start a new stuffing cycle. [08] In the operating mode according to the invention, the lowered ones clog

Tamping units never sleepers directly behind one another. During a stuffing cycle, there is always a processing distance of at least two threshold divisions. This prevents two tamping tools in the immediate vicinity from acting on the same ballast grains at the same time.

In this way, both the components of the tamping unit and the ballast grains mobilized during the tamping process are spared. In addition to a longer service life of the tamping tools, the result is a reduction in ballast abrasion. In addition, the immersion behavior of the tamping tools is improved.

In a further development of the method, a height adjustment drive and a vibration drive of the respective tamping unit are controlled by means of a common control device. A change in the height position and the application of vibrations to the respective tamping unit takes place in a coordinated manner by means of a common control. An additional sensor system for detecting the respective height position is not necessary, but advantageous.

It is also advantageous if the tamping tools of the respective tamping units are made to vibrate by means of an adjustable vibration drive and if a variable vibration frequency is specified for the respective vibration drive depending on a height position of the associated tamping unit. In this way, the vibration frequency can be reduced when the tamping unit is raised in order to reduce noise and to protect the moving components.

[11] The tamping tools are favorably acted upon with a higher oscillation frequency during a dipping process into the ballast bed than during a provision process. In the case of a hard ballast bed in particular, the resistance to immersion is reduced with an increased vibration frequency in that encrusted structures are broken up and the ballast grains are brought into a flow-like state. The provision process itself takes place with the optimal oscillation frequency (approx. 35 Hz).

In an advantageous embodiment of the method, at least two tamping units, the are not arranged directly one behind the other, lowered together, with a tamping unit arranged in between being lowered in a previous or subsequent method step. In this way, all sleepers below the tamping unit are tamped during a tamping cycle.

Another embodiment provides that during a tamping cycle at least two tamping units, which are not arranged directly one behind the other, are lowered together and that immediately afterwards the tamping unit is moved by a threshold division in the working direction for the next tamping cycle. In this operating mode, each sleeper is tamped several times to ensure high quality ballast compaction. Such multiple tamping is particularly useful for new track layers with a ballast bed that has not yet been pre-compacted.

A machine according to the invention comprises a tamping unit for the simultaneous tamping of several sleepers of a track positioned directly one behind the other by means of several tamping units arranged directly one behind the other, each tamping unit comprising a tool carrier which is height-adjustable by means of a height adjustment drive and on which opposing tamping tools are mounted, which vibrate via drives relocatable and can be ordered from one another. The machine is set up to carry out one of the described methods in such a way that all height adjustment drives are connected to a common control device and that control signals for staggered lowering and lifting processes are stored in the control device for the height adjusting drives of the tamping units arranged immediately one behind the other. A row tamping unit is used, the control of which has been modified for the present invention. In this way, the tamping processes of the tamping units arranged one behind the other are coordinated with one another by means of the control device.

[15] Each height adjustment drive is advantageously coupled to a displacement measuring device which is connected to the control device. Each distance measuring device supplies a distance measuring signal for the altitude of a assigned tool carrier. This means that the lowering and lifting processes of the individual tamping units can be precisely coordinated with one another. For example, the lowering process of the second group of tamping units begins shortly before the end of the lifting of the first group of tamping units. This shortens the respective stuffing cycle without reducing the listed advantages.

[16] Another improvement provides that the control device is coupled to a machine control for controlling a travel drive of the machine. This measure, too, leads to an optimization of the entire work process, in that the machine starts moving automatically as soon as the contact between the tamping tool and the ballast bed has ended during a tamping cycle.

[17] It makes sense to form a number of tamping tools arranged next to one another, together with the associated auxiliary cylinders, transversely to the longitudinal direction of the machine, to form a jointly controllable auxiliary group. This applies to the tamping units arranged next to each other, which tamp a sleeper on both sides of the two rails of the track. During operation, the additional groups are controlled jointly in order to ensure an even compression process along a threshold.

Brief description of the drawings

[18] The invention is explained below by way of example with reference to the accompanying figures. It shows in a schematic representation:

Fig. 1 machine with tamping unit

Fig. 2 tamping unit for tamping under three sleepers Fig. 3 tamping unit in front view

4 tamping unit for tamping under four sleepers; FIG. 5 tamping unit according to FIG. 2 with alternating activation of the tamping units

6 tamping unit according to FIG. 2 with activation of the front and rear tamping units for multiple tamping under the respective sleeper Description of the embodiments

The machine 1 shown in FIG. 1 is designed as a track tamping machine for tamping under three sleepers 4 mounted in a ballast bed 2 of a track 3. The machine 1 comprises a machine frame 6 which is supported on rail bogies 5 and on which a row tamping unit 7 is attached. In addition, the machine 1 comprises a lifting / straightening unit 8 for lifting and straightening the track grid formed from sleepers 4 and rails 9. A current rail position is recorded with a measuring system 10.

The tamping unit 7 is fastened to the machine frame 6 by means of an adjusting device 11. It comprises an assembly frame 12 with guides 13 and several tamping units 14. In a variant not shown, each tamping unit 14 is assigned its own assembly frame 12. Each tamping unit 14 comprises a tool carrier 15 which is mounted on the associated guides 13 in a height-adjustable manner by means of a height adjusting drive 16. On the respective tool carrier 15, opposing tamping tools 18 are pivotably mounted in a machine longitudinal direction 17.

In addition, a vibration drive 19 is arranged on the respective tool carrier 15, with which the tamping tools 18 are coupled via auxiliary cylinders 20. In an alternative variant, not shown, a hydraulic cylinder is arranged between the tool carrier 15 and the respective tamping tool 18, which is set up both as a vibration drive 19 and as an auxiliary drive 20. A pulsating hydraulic pressure is applied to the hydraulic cylinder to generate vibrations. During a setting process, the pulsating hydraulic pressure is superimposed on the setting pressure generated by the hydraulic cylinder.

[22] Each tamping tool 18 comprises a pivot lever 21 with an upper and a lower lever arm. The pivot lever 21 is mounted on the associated tool carrier 15, the upper lever arm being connected to the associated auxiliary drive 20. Two tamping tines 22 are usually attached to the free lower lever arm. [23] The opposite tamping tines 22 of the respective tamping unit 14 are at the same distance from a central vertical plane 23 in an initial position (FIG. 2). The distance between the central vertical planes 23 of the tamping units 14 arranged one behind the other corresponds to the smallest sleeper division t of the sleepers 4 to be tamped under. The dimensioning of the tamping units 14 in the machine longitudinal direction 17 is thus based on this smallest sleeper division t. The row tamping unit 7 shown in FIG. 1 is usually used for the simultaneous tamping of three sleepers 4 positioned one behind the other. The present invention relates to a modified mode of operation which ensures particularly gentle processing of the ballast bed 2.

[24] The flea actuators 16 are controlled by means of a common control device 24, with control signals for temporally staggered lowering and felling processes being stored in the control device 24. A displacement measuring device 25 is assigned to each height adjustment drive 16 to detect the flea position of the respective tool carrier 15. This includes, for example, a rope with a pull-wire sensor. As an alternative or in addition to this, position detection is integrated in the height adjustment drive 16, for example as a path measurement of a piston in a hydraulic cylinder.

[25] During a stuffing cycle, the height adjusting drives 16 are controlled in a staggered manner by means of the control device 23 on the basis of the control signals. Specifically, a first group of tamping units that are not arranged directly one behind the other is initially activated. In a variant of the method, a second group of tamping units that are not arranged directly one behind the other is controlled afterwards or across the board. In the case of comprehensive control, care must be taken that the tamping ax 22 of the second group only dip into the respective sleeper compartment when the tamping ax 22 of the first group is no longer in contact with the ballast. A tamping cycle is completed with the machine moving forward

1 in a working direction 26 in order to position the tamping unit 7 over the next sleepers 4 to be tamped. With so-called Continuously operating tamping machines, the tamping unit 7 is arranged on a separate machine frame 6 (tamping satellite). This separate machine frame 6 is attached to the main frame of the machine 1 so as to be longitudinally displaceable. The tamping unit 7 is repositioned above the track 3 by moving the machine 1 forwards and shifting the separate machine frame 6 relative to the main frame.

In Fig. 3 it can be seen that each rail 9 of the track 3 is assigned two separately lowerable tamping units 14. The tamping unit 7 thus comprises four tamping units 14 arranged next to one another in a row. In this case, the tamping unit comprises two juxtaposed combined tamping units 14 in a row.

A tamping unit 7 with four rows of tamping units 14 arranged directly one behind the other is shown in FIG. Here, viewed in the working direction 26, the tamping units 14 of the first and third rows are tied together to form the first group. In the illustration, these tamping units 14 are immersed in the ballast bed 2. The tamping units 14 of the second and fourth rows form the second group, which is then immersed in the ballast bed 2.

In another variant, the tamping units 14 on the outside of the rails of the first and third rows and the tamping units 14 on the inside of the rails of the second and fourth rows form the first group. The other stuffing units 14 form the second group. This also ensures that only tamping units 14 that are not arranged directly one behind the other are lowered into the ballast bed 2 at the same time. Each tamping unit 14 tampers the threshold 4 above which it is positioned. By moving the tamping unit 7 further in the working direction 26, the track 3 is completely tamped.

The processing of a track 3 with a tamping unit 7, which has three rows of tamping units 14, is described with reference to FIG. 5. The two images above show two process steps in a stuffing cycle. The tamping unit 7 remains positioned over the same point on the track 3. In the first step, a first group of tamping units 14 is lowered, provided and raised again. These are the tamping units 14 of the front and rear rows. The first group thus comprises eight tamping units 14, four of which are arranged next to one another in the front and rear rows.

[30] In the picture below, the tamping units 14 of the first group are again in the raised starting position. In the second step of the stuffing cycle, the middle stuffing units 14 are lowered, provided and raised again as the second group. In the example shown, these are four tamping units 14 arranged next to one another. The tamping cycle is ended by moving the tamping unit 7 further in the working direction 26 by three threshold divisions t. The two processing steps of the next tamping cycle are shown in the two images below. By means of a correspondingly further processing, the entire track 3 is tamped, with each sleeper 4 being tamped once.

[31] An alternative mode of operation is explained with reference to FIG. 6. Here, only the front and rear tamping units 14 are used in each tamping cycle. The middle tamping units 14 remain deactivated. Four stuffing cycles are shown in the four figures, each stuffing cycle being terminated with a forward movement of the stuffing unit 7 by a threshold division t. In this way, each sleeper 4 is tamped twice, first with the front tamping units 14 and in the next but one tamping cycle with the rear tamping units 14. The same applies to track elevations with large fleece values with previous introduction of new or cleaned ballast. The control direction 24 is set up for the various modes of operation. Each stuffing cycle is initiated by a triggering signal. In a simple form, the signal is triggered by means of an operating element that is actuated by an operator. If the machine 1 is equipped with a sensor system for detecting track objects (sleepers 4, rails 9, obstacles, etc.), an automated or partially automated control can take place. Tamping positions are automatically recognized by the sensors and the tamping unit 7 is moved to the correct place by means of drives. Once the stuffing units 14 are properly positioned, a stuffing cycle is activated.

[33] By means of the control signals stored in the control device 24, the lowering and lifting operations of the tamping units 14 take place in the specified sequence, which corresponds to the selected mode of operation. The coupling of the control device 24 with a machine control 27 also enables an automated forward movement of the tamping unit 7. The control device 24 reports to the machine control 27 that all the tamping units 14 are in the raised position again. The machine control 27 then activates a drive which moves the machine 1 (track construction machine or tamping satellite) forward.

Claims

1. A method for tamping under sleepers (4) of a track (3) stored in a ballast bed (2) by means of a tamping unit (7) for the simultaneous tamping of several sleepers (4) positioned one behind the other, with several in one working direction (26) directly tamping units (14) arranged one behind the other and height-adjustable independently of one another for tamping under a sleeper (4), characterized in that in a tamping cycle a first group of tamping units (14) not arranged directly one behind the other is first lowered into the ballast bed (2), provided and again is raised that preferably a second group of tamping units (14) not arranged directly behind one another is lowered into the ballast bed, provided and raised again and that the tamping unit (7) is moved further in the working direction (26) before the start of the next tamping cycle.

2. The method according to claim 1, characterized in that a height adjustment drive (16) and a vibration drive (19) of the respective tamping unit (14) are controlled by means of a common control device (24).

3. The method according to claim 1 or 2, characterized in that tamping tools (18) of the respective tamping units (14) are made to vibrate by means of an adjustable vibration drive (19) and that for the respective vibration drive (19) depending on a height position of the associated tamping unit (14) a variable oscillation frequency is specified.

4. The method according to claim 3, characterized in that the tamping tools (18) are acted upon during a dipping process in the ballast bed (2) with a higher oscillation frequency than during a provision process.

5. The method according to any one of claims 1 to 4, characterized in that during a stuffing cycle in one method step at least two stuffing units (14) which are not arranged directly one behind the other, are lowered together, and that a tamping unit (14) arranged between them is lowered in a previous or subsequent method step.

6. The method according to any one of claims 1 to 4, characterized in that during a stuffing cycle at least two stuffing units (14), which are not arranged directly one behind the other, are lowered together and that immediately afterwards the stuffing unit (7) for a next stuffing cycle by one Threshold division (t) is moved in the working direction.

7. Machine (1) with a tamping unit (7) for the simultaneous tamping of several sleepers (4) of a track (3) positioned directly one behind the other by means of several tamping units (14) arranged directly one behind the other, each tamping unit (14) having one by means of a height adjustment drive ( 16) comprises a height-adjustable tool carrier (15) on which opposing tamping tools (18) are mounted, which can be set in vibration via drives (19, 20) and can be ordered with respect to one another, characterized in that the machine (1) is designed to execute a The method according to one of claims 1 to 6 is set up that all height adjustment drives (16) are connected to a common control device (24) and that in the control device (24) for the height adjustment drives (16) of the tamping units (14) arranged directly one behind the other control signals for Staggered lowering and lifting processes are stored.

8. Machine (1) according to claim 7, characterized in that each height adjustment drive (16) is coupled to a displacement measuring device (25) and that each displacement measuring device (25) is connected to the control device (24).

9. Machine (1) according to claim 7 or 8, characterized in that the control device (24) is coupled to a machine control (27) for controlling a travel drive of the machine (1).

10. Machine (1) according to one of claims 7 to 9, characterized in that transversely to the machine longitudinal direction (17) a plurality of juxtaposed Tamping tools (18) together with the associated auxiliary cylinders (20) form a jointly controllable auxiliary group.