EP4031712B1 - Machine and method for stabilizing a track - Google Patents

Description

field of technology

The invention relates to a machine for stabilizing a track, with a machine frame supported on rail chassis and a height-adjustable stabilization unit that can be rolled on rails of the track by aggregate rollers, which has a vibration exciter with rotating unbalanced masses to generate an impact force acting dynamically in a track level normal to a longitudinal direction of the track, as well as a Height drive to generate an effective load on the track. The invention also relates to a method for operating such a machine.

State of the art

Today's recognized maintenance measures in the track include compacting the ballast bed using dynamic track stabilizers after tamping work. This method not only increases the lateral displacement resistance of the track grating, but also ensures high track quality over a longer period of time.

The compaction effect is influenced by several parameters, including compaction frequency, vibration amplitude, vertical load and dynamic impact force. The frequency is limited to the range of around 32-38 Hz due to the material behavior of the gravel. In this area the ballast bed shows optimal behavior.

Machines for stabilizing a track are already known several times from the prior art. In a so-called dynamic track stabilizer, stabilization units located between two rail chassis are lowered onto a track to be stabilized via a height adjustment and applied with a vertical load. About aggregate rollers and on the outside of the rail heads The adjacent pincer rollers transmit a transverse vibration of the stabilization units to the track with continuous right-of-way.

Such a machine is, for example, from the WO 2008/009314 A1 known. The stabilization unit includes adjustable unbalance masses in order to quickly reduce the impact force to a reduced value or to zero if necessary (e.g. in the case of solid structures, such as bridges or tunnels) and to raise it to the original value immediately after reaching a section of track to be stabilized.
Another machine for track stabilization according to the preamble of claim 1 is out WO 2019/158288 A1 known.

Since the frequency can only be varied within a limited range, the approach has been to vary the impact force by adjusting the position of the eccentric masses. A disadvantage here is the structural design of the moving parts, which is very complicated and complex to implement. This also results in corresponding costs for maintenance and repair.

Summary of the invention

The invention is based on the object of providing a machine of the type mentioned at the outset to provide a significant improvement in the economic efficiency of operation, in relation to the maintenance effort, compared to the prior art, through the simplest, most robust construction of the stabilization unit. In addition, a process carried out using the machine to compact the ballast bed of the track superstructure should be specified.

According to the invention, these tasks are solved by a machine according to claim 1 and a method according to claim 10. Dependent claims specify advantageous embodiments of the invention.

The invention provides that a main unbalanced mass and a secondary unbalanced mass cause different centrifugal forces at the same rotation speed depending on the direction of rotation, the two unbalanced masses being coupled in such a way that when rotating in one direction of rotation, the unbalanced masses have a first phase shift relative to one another and that when rotating in the opposite direction of rotation the unbalanced masses to each other one of the have a second phase shift that deviates from the first phase shift. Depending on the arrangement of the unbalanced masses, a changed phase shift changes both the direction and the strength of the impact force.

At least one main unbalanced mass and at least one secondary unbalanced mass are assigned to a rotary shaft, the main unbalanced mass being firmly connected to the shaft. This shaft-hub connection is designed with a positive, non-positive or material fit.

The secondary unbalance mass is mounted in such a way that it can rotate freely within a defined angular range. This defined angular range is determined depending on the drive direction of rotation and thus results in two possible phase shifts of different amounts between the main unbalanced mass and the assigned secondary unbalanced mass, with end stops in the respective direction of rotation determining the position of the main unbalanced mass relative to the secondary unbalanced mass. For the further explanations, a main unbalanced mass and an associated secondary unbalanced mass around the same axis of rotation are referred to as an unbalanced mass pair.

The main components of the stabilization unit in its structurally simplest possible structure are a rotation shaft and an unbalanced mass pair, consisting of a main unbalanced mass and a secondary unbalanced mass.

It is advantageous if the secondary unbalanced masses are driven by the main unbalanced masses in a form-fitting manner, thus purely passively, by so-called drivers. It is structurally possible to design these drivers as independent components, but the driver function can also be integrated into a single component by appropriately designing the main unbalanced masses. This special design or geometric arrangement of the drivers results in a predefined angular range in which free rotational movement of the secondary unbalanced masses between the end stops is possible.

In a particularly advantageous development, the stabilization unit comprises two counter-rotating units coupled via gears Rotary shafts and the unbalance mass pairs associated with each shaft. Depending on the alignment and phase position of the unbalanced mass pairs relative to each other and thus the individual centrifugal forces and their different directions of action, the force vectors in the machine housing are added or subtracted. It is usually provided that all centrifugal force components subtract in the vertical direction, thus canceling out, while the centrifugal force components add in the horizontal direction, so that the resulting, maximum possible total impact force is achieved in the horizontal effective direction. This results in at least two impact forces that differ in magnitude in order to be able to specifically change the impact force acting on the track.

It is also advantageous if the respective unbalance mass is arranged on the stabilization unit with a rotation axis aligned in the longitudinal direction of the track. This alignment is particularly suitable for use in a stabilization unit, as the resulting impact force acts on the track to be stabilized normal to the longitudinal direction of the track. This ensures optimal energy input into the track.

It can also be advantageous that at least two pairs of unbalanced masses are assigned to a rotary shaft, the pairs of unbalanced masses each comprising a main unbalanced mass and a secondary unbalanced mass around the same axis of rotation. Depending on the requirement for the total impact force or its amount, several pairs of unbalanced masses can be arranged in series on a rotation shaft.

The operation of two stabilization units on one machine is possible either coupled, using a common drive, or independently of each other using independent drives for each stabilization unit.

If, in an advantageous development, two independently driven stabilization units are used on one machine, up to eight impact forces with different magnitudes can be controlled; this results mathematically from 3 ² - 1 = 8.

In one embodiment of the invention it is provided that in the case of stabilization units that are driven independently of one another, the respective drives are controlled by means of a common control device.

This means that the individual drives can be optimally coordinated with one another and controlled precisely. Phase synchronization of the uncoupled stabilization units can ensure either co-oscillating or counter-oscillating operation. This is particularly advantageous for controlling the 8 different impact forces mentioned above.

In a simple embodiment, at least two stabilization units are operated coupled on one machine, for example via a cardan shaft. Here, a common drive enables a very compact design of the overall arrangement.

To drive the rotation shaft, it is provided that the drives are designed as hydraulic actuators. This means that the drives can be integrated into an existing hydraulic system of the machine.

In another embodiment of the invention, it can be advantageous if the respective drives are designed as electrical actuators. A sensible integration is possible, especially with new machine concepts that provide for modern and more efficient overall operation with power supply via accumulators or overhead lines.

The method according to the invention for operating a machine provides that at least one stabilization unit is placed on the track via a height drive and is subjected to a load and that at least one pair of unbalanced masses is driven via a rotation shaft with a switchable direction of rotation. This ensures track stabilization with variable impact force that can be adapted to local conditions.

In a favorable development of the method, increasing the drive power of a drive of the stabilization unit is regulated via a so-called soft start. A predefined, increasing ramp course is stored in a higher-level control system, which enables a targeted ramp-up within a defined period of time in order to avoid shocks in the end stops of the unbalanced masses.

A further embodiment of the method enables variable adjustment of the impact force in the range between selectable impact force levels by changing the speed of the respective, associated drive. This offers the operator great flexibility and precision in track stabilization.

Brief description of the drawings

Fig. 1

Seitenansicht einer Maschine zum Stabilisieren eines Gleises

Fig. 2

Stabilisationsaggregate unabhängig, mit eigenem Antrieb

Fig. 3

Stabilisationsaggregate gekoppelt, mit gemeinsamem Antrieb

Fig. 4

Detailansichten eines Stabilisationsaggregats / Schnittdarstellungen

Fig. 5

Drehrichtungsabhängige Unwuchtverstellung über Mitnehmer

Fig. 6

Unwuchtverstellung durch Drehzahlregelung im Zwischenbereich

The invention is explained below in an exemplary manner with reference to the attached figures. It shows in a schematic representation:

Fig. 1

Side view of a machine for stabilizing a track

Fig. 2

Stabilization units independent, with their own drive

Fig. 3

Stabilization units coupled with a common drive

Fig. 4

Detailed views of a stabilization unit / sectional views

Fig. 5

Direction-dependent unbalance adjustment via driver

Fig. 6

Unbalance adjustment through speed control in the intermediate range

Description of the embodiments

Fig. 1 shows a simplified machine 1 for stabilizing a track 3 resting on ballast 2, which includes a machine frame 6 supported on rails 5 by rail chassis 4. Between the two rail chassis 4 positioned at the ends, two stabilization units 7 are arranged one behind the other in the longitudinal direction 8 of the track. These are each connected to the machine frame 6 in a vertically adjustable manner by height drives 9.

A measuring system 27 for recording the rail geometry is attached to the machine frame 6. A control device 26 is set up to process the data received from the measuring system 27, as well as to determine the control parameters for operating and controlling the stabilization units 7, the height drives 9 and the drives 13.

The execution in Fig. 1 represents independent, uncoupled stabilization units 7 with their own drives 13. In the following Characters ( Fig. 2 and Fig. 3 ) possible designs with both coupled and uncoupled stabilization units 7 are shown.

In Fig. 2 Independent stabilization units with their own drive are shown. With the help of aggregate rollers 10 that can be rolled on the rails 5, each stabilization unit 7 can be brought into positive engagement with the track 3 in order to cause it to oscillate at a desired oscillation frequency. The aggregate rollers 10 include for each rail 5 two wheel flange rollers, which roll on the inside of the rail 5, and a tong roller, which is pressed against the rail 5 from the outside by means of a tong mechanism 11 during operation. The height drives 9 apply a vertical static load to the track 3.

The drives 13 of the stabilization unit 7 are connected to a common supply device 25. In the case of electric drives 13, this is, for example, a motor-generator unit with power from an electrical storage unit. An overhead line can also be used to supply electric drives 13 if the machine 1 has current collectors and corresponding converters. If hydraulic drives 13 are used, the supply device 25 is usefully integrated into a hydraulic system of the machine 1.

An alternative shows Fig. 3 with coupled stabilization units and a common drive. The basic structure of the stabilization units 7 is with the execution in Fig. 2 identical, the difference here lies in the coupling of the arrangement in the longitudinal direction of the track 8 and the design of the drives 13. The stabilization units 7 are connected to each other in terms of drives via a connecting shaft 15. The drive 13 and the connecting shaft 14 are simply designed.

In Fig. 4 one of the stabilization units 7 is shown in detail in sectional views. A vibration exciter 17 is arranged within a housing 16 and has a rotation shaft 18 with unbalanced masses arranged thereon on two rotation axes 21. A main unbalance mass 19 and a secondary unbalance mass 20 form unbalanced mass pair. Each rotation shaft 18 is rotatably mounted on both sides in the housing 16 via roller bearings 22.

The unbalanced masses 19, 20 are coupled via so-called drivers 24, which are designed here as independent elements. These are congruently attached directly to the main unbalanced mass 19 as well as to the secondary unbalanced mass 20.

The counter-rotating rotation shafts 18 are mechanically coupled via gears 23, with the power transmission to the rotation shaft 18 taking place in a form-fitting manner via a keyway connection.

The secondary unbalanced masses 20 are freely rotatable via plain bearings on the rotary shaft 18, the main unbalanced masses 19 are firmly connected to the rotary shaft 18 via a keyway connection.

The ones in here Fig. 4 The construction presented shows two pairs of unbalanced masses arranged axially on the rotary shafts 18, that is to say two main unbalanced masses 19 each with two secondary unbalanced masses 20. The technically simplest solution is a structure with only one rotary shaft 18 and only one pair of unbalanced masses arranged thereon.

Fig. 5 shows the direction of rotation-dependent unbalance adjustment via driver 24 schematically. The illustrations A, B, C, D, E, F, G, H show the angular positions 0°, 90°, 180° and 270° for both directions of rotation, each Representation composed of an upper and a lower rotation shaft 18. The specified direction of rotation is always related to the upper rotation shaft 18, the lower rotation shaft 18 rotates in the opposite direction of rotation through mechanical coupling.

Illustrations A to D show right-hand operation (clockwise direction of rotation) while illustrations E to H show left-hand rotation operation (counter-clockwise direction of rotation).

The structure in illustration A (angular position 0°) includes the upper, clockwise rotating shaft 18 with a pair of unbalanced masses arranged thereon. The main unbalanced mass 19 with associated drivers 24 (fine hatched) causes a centrifugal force F1 from the pivot point in the vertical direction, the secondary unbalanced mass 20 with associated drivers 24 (coarse hatched) also causes a centrifugal force F3 from Pivot point out in vertical direction. The sum of the two centrifugal forces F1 and F3 results in the total centrifugal force Fges1. On the lower rotation shaft 18 (counterclockwise), the total centrifugal force Fges1 acts as the sum of F2 and F4 with the same amount in the opposite direction, the forces are therefore canceled out when reduced to the entire stabilization unit 7, there is no force in the vertical direction.

In representation B (angular position 90°), the total centrifugal force Fges1 acts from the pivot point in the horizontal direction. The same force situation exists on the lower rotation shaft 18 (counterclockwise), here the total centrifugal force Fges1 acts as the sum of F2 and F4 with the same amount in the same direction, the forces add up and result in 2*Fges1, the maximum possible impact force in the horizontal direction on the track 3.

The resulting forces behave analogously to representations A and B in representations C (angular position 180°) and D (angular position 270°); here there is also a cancellation (C) and a doubling (D) of the total centrifugal forces Fges1.

The structure in illustration E (angular position 0°) now shows a counterclockwise rotating shaft 18 with a pair of unbalanced masses arranged on it. The changed direction of rotation results in a different angular position of the two unbalanced masses 19, 20 relative to one another. The main unbalanced mass 19 with associated drivers 24 (fine hatched) causes a centrifugal force F1 from the pivot point in the vertical direction upwards, the secondary unbalanced mass 20 with associated drivers 24 (coarse hatched) causes a centrifugal force F3 from the pivot point in the vertical direction downwards. The sum of the two centrifugal forces F1 and F3 results in the total centrifugal force Fges2. On the lower rotation shaft 18 (counterclockwise), the total centrifugal force Fges2 acts as the sum of F2 and F4 with the same amount in the opposite direction, the forces are therefore canceled out when reduced to the entire stabilization unit 7, there is no force in the vertical direction.

In representation F (angular position 90°), the total centrifugal force Fges2 acts from the pivot point in the horizontal direction. The same force situation exists on the lower rotation shaft 18 (counterclockwise), the total centrifugal force acts here Fges2 as the sum of F2 and F4 with the same amount in the same direction, the forces add up and result in 2*Fges2, the minimum possible impact force in the horizontal direction on track 3.

The resulting forces behave analogously to the representations E and F in the representations G (angular position 180°) and H (angular position 270°); here there is also a cancellation (G) and a doubling (H) of the total centrifugal forces Fges2.

Fig. 6 shows using a diagram how the impact force can be variably adjusted by low speed control. If two independently driven stabilization units 7 are used on a machine 1, up to eight impact forces of different magnitudes can be controlled; this results from 3 ² - 1 = 8.

The range between the impact force levels can now be compensated for within a very narrow frequency band by changing the speed of the respective, associated drive 13. When all intermediate areas (line in thick lines) of the impact force levels S1-S7 are completely passed through, a so-called frequency control funnel is created (line lines dotted). The impact force F in % is shown on the ordinate above the abscissa with the frequency f in Hz.

Claims (12)

1. A machine (1) for stabilising a track (3), with a machine frame (6) supported on rail-based running gears (4) and at least one height-adjustable stabilising unit (7) which can be rolled on rails (5) of the track (3) by means of work unit rollers (10), comprising a vibration exciter (17) with rotating unbalanced masses (19, 20) for generating an impact force acting dynamically in a track plane normal to a longitudinal direction of the track (8), and a linear drive (9) for generating a load acting on the track (3), characterised in that a main unbalanced mass (19) and a secondary unbalanced mass (20) produce different centrifugal forces at the same rotational speed depending on the direction of rotation, the two unbalanced masses (19, 20) being coupled in such a way that, during rotation in one direction of rotation, the unbalanced masses have a first phase shift with respect to one another, that, when rotating in the opposite direction of rotation, the unbalanced masses have a second phase shift to each other which differs from the first phase shift and that two unbalanced masses (19, 20), each dependent on the direction of rotation, are mechanically coupled by means of positive engagement or constructive elements, so-called catches (24), thus forming a pair of unbalanced masses and one of two predetermined phase shifts results therefrom depending on the direction of rotation.
2. A machine (1) according to claim 1, characterised in that the machine (1) has at least two counter-rotating rotation shafts (18) which are coupled via gearwheels (23).
3. A machine (1) according to one of the claims 1 or 2, characterised in that the respective unbalanced mass (19, 20) is arranged on the stabilising unit (7) with an axis of rotation (21) aligned in the longitudinal direction of the track (8).
4. A machine (1) according to one of the claims 2 tor 3, characterised in that at least two pairs of unbalanced masses are assigned to a rotation shaft (18), the pairs of unbalanced masses each comprising a main unbalanced mass (19) and a secondary unbalanced mass (20) on the same axis of rotation (21).
5. A machine (1) according to one of the claims 1 to 4, characterised in that when at least two stabilising units are used, each stabilising unit (7) is assigned its separate drive (13).
6. A machine (1) according to claim 5, characterised in that the respective drives (13) are actuated by means of a shared control device (26).
7. A machine (1) according to one of the claims 1 to 4, characterised in that when at least two stabilising units (7) are used, a shared drive (13) is assigned to the overall arrangement of the individual stabilising units (7).
8. A machine (1) according to one of the claims 5 or 7, characterised in that the respective drive (13) is designed as a hydraulic actuator.
9. A machine (1) according to one of the claims 5 or 7, characterised in that the respective drive (13) is designed as an electric actuator.
10. A method for operating a machine (1) according to one of the claims 1 to 9, characterised in that the respective stabilising unit (7) is set down on the track (3) via a linear drive (9), that a load is applied to it, and that the associated rotation shaft (18) is driven by the assigned drive (13) with a reversible direction of rotation.
11. A method according to claim 10, characterised in that an increase in the driving power of a drive (13) of the stabilising unit (7) is controlled via a so-called soft start, wherein a predefined, increasing ramp is stored in a higher-level control system, which enables a targeted increase within a defined period of time.
12. A method according to one of the claims 10 or 11, characterised in that a variable adjustment of the impact force in the range between possible impact force levels takes place by changing the engine speed of the respective associated drive (13).

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