WO2011072762A1

WO2011072762A1 - Method and device for profiling a running surface geometry of track components

Info

Publication number: WO2011072762A1
Application number: PCT/EP2010/005760
Authority: WO
Inventors: Dirk Nicklisch; Volkmar Sauer; Andreas Martin
Original assignee: Db Netz Ag
Priority date: 2009-12-15
Filing date: 2010-09-21
Publication date: 2011-06-23
Also published as: DE102009058190A1

Abstract

The invention relates to a method and device for profiling a geometry of track components of rail transport routes in a region in which said track components come in contact with wheels of rail vehicles, a so-called running surface geometry. A measuring system detects the course of a path of a wheel provided with a reference wheel profile as said wheel rolls over the respective track component in a spatially fixed coordinate system. The track component is assessed with regard to the dynamic effects thereof using a data processing system. A data processing system determines an optimised target path that is based on the measured path, which target path can be achieved within the scope of tolerances for material removal from the track component. A material-removing machine tool, which is shaped such that when machining the track component it removes the material in a shape matching a predefined wheel profile, subsequently machines the track component along the identified target path.

Description

Method and device for profiling an overflow geometry of track components

The invention relates to a method and a device for profiling a geometry of track components of rail traffic routes in an area in which these track components are touched by wheels of rail vehicles, a so-called overflow geometry.

To ensure safe and economical railway operation track components - such as frogs in points, rail extensions o.ä. - be subjected to a regular inspection and, if necessary, a repair with regard to their geometric condition, so that further damage or failure of the component can be ruled out until the subsequent inspection. Deviations from a specified setpoint geometry (for example, extensions on the frog and wing rail) must be measured in order to be able to derive necessary corrective measures.

In the prior art, a check of the overflow geometry in a turnout only includes a test and assessment of a frog ramp and a frog tip using simple measuring means (ruler, measuring wedge or measuring point probe). Here, measuring point probes, rulers and heart gauge gauges are used. In addition, a height difference between the top edge of the frog and a wing rail in a cross section "L1", a theoretical wheel overflow, and "L" is measured by means of a heart gauge.

Then, if necessary, the track component is reworked by build-up welding and subsequent grinding.

Disadvantage of these methods, however, is that they are inaccurate, time consuming and heavily influenced by subjective influences of serving and evaluating staff. Furthermore, it is not possible to infer the dynamic effects of observed deviations from the desired geometry from recorded measured variables, since the frog ramp is detected only occasionally and an actual vertical movement of a wheel due to Wheel and rail filgeometry can clearly distinguish from the detected by reference to a rail top edge ramp course.

DE 10 2004 016 828 A1 discloses a method for testing and assessing a geometry of track components of rail traffic routes, in which the spatial course of the trajectory of a wheel provided with a reference wheel profile is determined directly or indirectly during the rolling over of the respective track component in a spatially fixed coordinate system and subsequently be assessed in terms of its dynamic impact.

The advantage here is that the validity of the examination of the geometric state by the determination of the vertical movement of a component rolling over the wheel in a spatially fixed coordinate system and their subsequent computer-aided evaluation is significantly improved and objectified. In particular, a high measurement accuracy is achieved with a high measurement speed. The entire area of the design-related lowering and subsequent lifting of the wheel (wing rail bend to K point) is continuously recorded and assessed. With the method it is also possible to determine the effects of the cross profile wear of wing rail and / or frog on the wheel overflow.

DE 10 2004 017 746 B4 discloses a method and a device for detecting the condition and for processing switches in track systems. In the process, a three-dimensional profile image of the overflow area of a switch frog piece is created with the aid of a measuring system and a scanner unit, as well as gauge, elevation, connection, groove width, longitudinal and directional arrow heights. The actual profile data is sent to a data processing system and analyzed. By means of a numerical algorithm, desired profile data for the geometric description of the switch frog are generated. These desired profile data are delivered together with the actual profile data to a processing unit, which reworks the points frog piece especially with grinding technology.

However, the process is very complex, since a complete three-dimensional profile image of the actual state is created with a high measurement and computational effort. The subsequent processing of the track system is very complex, since in turn a three-dimensional target profile must be incorporated into the track system, preferably by consuming grinding.

From EP 2 071 078 A1 an apparatus and a method for processing rails, in particular grooved rails are known, wherein the device a milling device, preferably having a milling head rotating about the vertical axis. The contour of the milling head can also correspond to the contour of the rail profile to be produced. The disadvantage of this method is that the machining takes place either manually or by means of preprogrammed movement sequences. It is not determined based on the existing condition of the track system, optimized trajectory of a reference wheel profile and responded flexibly to different actual states.

It is therefore an object of the invention to provide a method and a device with which the disadvantages of the prior art in the assessment and processing of the overflow geometry of track components are solved.

This object is achieved in connection with the preamble of the main claim according to the invention by the features of the method specified in claim 1 and by the features specified in claim 2 of the device for implementing the method.

According to claim 1, the two-dimensional course of the trajectory of a provided with a Referenzradprofil wheel or measuring roller when rolling over the respective track component in a spatially fixed coordinate system is determined and evaluated using a data processing system in terms of its dynamic effects.

The advantage here is that the validity of the examination of the geometric state by the inventive determination of the vertical movement of a component rolling over the wheel in a spatially fixed coordinate system and their subsequent computer-aided evaluation is highly accurate and objek- tive. The entire area of the design-related lowering and subsequent lifting of the wheel (wing rail bend to K point) is continuously recorded and assessed. In addition, it is possible to determine the effects of the cross profile wear of wing rail and / or frog on the wheel overflow.

In order to carry out this test, it is therefore not necessary to elaborately record and analyze a three-dimensional profile of the track component. It is entirely sufficient for maintenance to record and analyze the dynamic processes involved in overrunning the wheel via the track component.

Investigations have shown that there is a direct relationship between the vertical wheel movement and the forces occurring between wheel and rail and thus further damage to the component. For the size The forces are not only the amplitude of the vertical movement of the Radschwerpunktes, but also the increase and the curvature of its trajectory crucial. Therefore, corresponding intervention thresholds for the repair must be specified for these variables. The concrete definition of intervention thresholds is influenced by numerous constraints and must be based on a technical and economic analysis by the infrastructure manager. The frame parameters used in particular are the load-bearing capacity of the material to be processed and the speed with which rail vehicles pass over the trackside to be processed.

Using these intervention thresholds, the data processing system analyzes the possibilities of optimizing the profile of the track system, which led to the measured actual trajectory of a reference wheel profile, using a material-removing machining tool. Depending on the frame parameters, a data processing system determines the tolerance ranges for the slope and the curvature of the Radabsenkungskurve. The data processing system is equipped with software with which it calculates a desired trajectory curve for a wheel profile which is equivalent to the reference wheel profile and which lies within the previously determined tolerance ranges. The goal is to ensure a long service life of the machined area by minimizing material removal. Since each track component is subject to different loads and i.a. has its own characteristic Radabsenkungskurve, this is done individually for each measured track component. A material-removing machining tool uses this data to process the track component, preferably fully automatically, in such a way that a wheel profile that corresponds to the reference wheel profile on the track component describes a trajectory that corresponds to the desired trajectory.

Claim 2 includes an apparatus for implementing the method of claim 1.

In this case, a wheel provided with a reference wheel profile or a measuring roller determines the two-dimensional course of the trajectory in a spatially fixed coordinate system when the track component rolls over. A data processing system records the measured values and evaluates them with regard to their dynamic effects.

The advantage here is that the validity of the test of the geometric state by the inventive determination of the vertical movement of a nes the wheel rolling over the component in a spatially fixed coordinate system and their subsequent computer-aided evaluation are highly accurate and objective. The entire area of the design-related lowering and subsequent lifting of the wheel (wing rail bend to K point) is continuously recorded and assessed. In addition, it is possible to determine the effects of the cross profile wear of wing rail and / or frog on the wheel overflow.

In order to be able to carry out this test, it is therefore not necessary to elaborately record and analyze a three-dimensional profile of the track component. It is entirely sufficient for the maintenance to record and analyze the dynamic processes when the wheel overflows over the track component ,

Investigations have shown that there is a direct relationship between the vertical wheel movement and the forces occurring between wheel and rail and thus further damage to the component. For the size of the forces not only the amplitude of the vertical movement of the Radschwerpunktes, but also the increase and the curvature of its trajectory are crucial. Therefore, corresponding intervention thresholds for the repair are specified in the data processing system for these variables. The concrete determination of the intervention thresholds is influenced by numerous boundary conditions and is based on a technical and economic analysis by the infrastructure manager.

Using these intervention thresholds, the data processing system analyzes the possibilities of optimizing the profile of the track system, which led to the measured actual trajectory of a reference wheel profile, using a material-removing machining tool. As a framework parameters serve in particular the strength of the material to be processed and the speed with which rail vehicles run over the track system to be processed. Depending on the frame parameters, the data processing system determines the tolerance ranges for the slope and the curvature of the Radabsenkungskurve. The data processing system calculates a desired trajectory curve for a wheel profile which equals the reference wheel profile and which lies within the previously determined tolerance ranges. Furthermore, the smoothest possible transition between the machined and unprocessed section of the track component must be ensured. For this purpose, it is advantageous to design the connection of the desired trajectory curve to the transition point to the actual trajectory tangentially. The goal is to ensure a long service life of the machined area by minimizing material removal. Since every track component subject to different loads and ia has its own characteristic Radabsenkungskurve, this is done individually for each measured track component.

The device contains, in addition to the measuring device, which determines the course of a trajectory of a wheel provided with a reference wheel profile when rolling over the respective track component in a spatially fixed coordinate system, nor a material removing machining tool which is shaped so that it in the preferably fully automated processing of the track component, the material in the form of a given profile abträgt. This takes place in the form that a wheel profile which equals the reference wheel profile, after machining on the track component, describes a trajectory which corresponds to the desired trajectory curve. This makes it possible that only the desired trajectory of the selected Referenzradprofils must be considered for processing the track component. The method and the device are thereby independent of the detailed profile structure of the track component, since only the interaction between the reference wheel profile and the track component plays a role. It is therefore not necessary to determine the actual profile of the track component exactly.

If the material-removing part of the machining tool is such that it automatically incorporates a profile matching the desired shape of the selected reference wheel profile into the track component, it must only be guided over the track component in accordance with the determined target trajectory of the reference wheel profile. This is achieved by guiding the machining tool over the track component within a base unit serving as a reference frame in a spatially fixed coordinate system in such a way that it follows the determined target trajectory during the material-removing machining. The spatially fixed coordinate system is preferably the same as that used during the measurement of the actual trajectory. For this purpose, it is advantageous to install both the measuring device and the material-removing machining tool in a common frame of reference. But it is also possible to use the measuring device and the machining tool independently. In this case, the data processing system must perform a coordinate transformation between the measurement and the machining coordinate system. For this, reference points outside the measuring and routing device must be defined and measured. According to claim 3, the machining tool is a milling machine. It has the advantage over grinding machines that the milling head can be selected in a form that already corresponds to the desired profile for the track component. In addition, the surface of the machined track component is more level than after the grinding process. The milling machine must be so flexible in its degrees of freedom that it is ensured that the milling head of the spatial trajectory, which is given by the target trajectory, can follow exactly. Ideally, the milling machine is aligned so that the milling head must be deflected only vertically during its feed motion.

The invention will be explained in more detail below with reference to an embodiment of three figures.

Fig. 1 shows schematically a method for assessing the overflow geometry of a switch by means of a measuring roller in plan view; if the measuring roller is replaced by the similar-looking milling head, the figure also applies as a schematic representation of the milling process.

2 schematically shows the measuring roller on the track component to be processed as a vertical sectional image.

FIG. 3 shows, by way of example, a measured course of a wheel depression in the case of a worn center piece (solid line), together with a calculated setpoint trajectory (dashed line).

A particularly advantageous embodiment relates to a direct mechanical scanning of the geometry of the track during the measuring process. According to FIG. 1 and FIG. 2, a measuring roll 1 which is vertically and horizontally movable in a plane parallel to the track plane is guided with the shape of the reference wheel profile over the region of the possible vertical depression 3, for example in the overflow region of a switch frog piece. The trajectory, that is to say the lowering curve of the measuring roller 1 over the rolling path 4, is continuously recorded (see FIG. 3, solid line 9) and subsequently evaluated with the aid of an evaluation software in a data processing system. For large required spans, it may be necessary to provide a way of compensating the deflection of the measuring base 2 (eg an "optical tendon") .The measuring base 2 serves as a reference for a spatially fixed three-dimensional coordinate system within which the trajectory 9 is described. A software in a data processing system now analyzes whether it is necessary and, if so, whether it is possible to optimize the overflow area of the switch by material removal within predetermined tolerances 1 1. If, for example, there is too great a curvature 16 of the Radabsenkungskveve at its lowest point (see Figure 3), so much material must be removed right and left of this point that the curvature 15 comes to rest within a tolerance range 13. The slope of the curve 13, or 14 left and right of the lowest point is also to be considered. So that a wheel does not lose contact with the track component during the crossing, the gradient 13 must not be too pronounced in the sloping area. Similarly, on the right side of the curve, in the rising area, the slope 13 may also not be too strong, otherwise the dynamic load of the track component in the crossing of a train is too high.

Furthermore, the desired trajectory curve 12 must be designed so that a tangential connection 10 is ensured to the existing trajectory 9.

In addition, after the track component has been processed, sufficient material still has to be present to ensure safe operation. Since the interaction between wheel and track component depends on the one hand on dynamic parameters, e.g. the speed and weight of the trains moving over the track component and, on the other hand, the mechanical strength of the material and the like; depends on the material used, all these parameters must be included to determine an individual, optimal target trajectory 12. Therefore, software determines the optimized target trajectory 12 that a wheel with a wheel profile corresponding to the reference wheel profile of the measuring roller 1 should pass through when it passes the overflow area of the point. The control unit of a machining tool now uses the data of the measured trajectory 9. Within the coordinate system previously defined by the measuring base 2, a milling head 1 whose shape is chosen to match the desired reference wheel profile is followed by the machining tool following the optimized nominal trajectory 12 , guided over the overflow area of the switch. Wherever the milling head meets the track, it carries material accordingly, so that after the machining process, a wheel with the corresponding wheel profile according to the desired trajectory 12 passes over the overflow area of the point.

If the measurement of the track component reveals that although it is necessary to machine the track component, the evaluation software in the data processing system calculates that, for example because of advanced wear, is not possible to produce by material removal a tolerable target trajectory, the track component would have to be prepared by welding a coating before further processing. For this purpose, the software calculates at which point of the switch how much material must be welded onto the track component. After welding, the process is repeated as described above.

A second embodiment relates to the case that the coordinate systems of the measuring base do not necessarily coincide with the coordinate system of the machining tool. In this case, the position of the coordinate systems relative to one another must be specified in a common spatially fixed frame of reference. This can be ensured, for example, by a measuring frame aligned parallel to the track plane. Furthermore, the solid spatial reference can be produced, for example, by combining the profile measuring technique or the machining tool, in each case with an inertial system (gyro platform). The position of the moving measuring system or machining tool in space is continuously determined and recorded. This information ensures that the two coordinate systems can be correctly transformed into each other.

LIST OF REFERENCE NUMBERS

1 measuring roller or milling head

2 measuring base

3 range of vertical lowering

4 taxiway

5 Direction of movement of the deflection of the measuring roller

6 wing rail

7 centerpiece tip

8 wing rail

9 trajectory for worn heart

10 Tangential connection

1 1 Tolerable material removal

12 Optimized target trajectory

13 steepest climbs - optimized

14 steepest climbs - worn

15 max. Curvature - optimized

16 max. Curvature - worn

17 maximum lowering

18 in the direction of Flügelschienenknick

19 in the direction of K-Punkt

Claims

claims

1 . A method for profiling an overflow geometry of track components, characterized in that - a course of a trajectory of a provided with a reference wheel profile when rolling the respective track component determined in a spatially fixed coordinate system and evaluated by a data processing system in terms of its dynamic effects, - using the data processing system on the measured

Trajectory based, optimized target trajectory is determined, which can be achieved within tolerable material removal of the track component, automatically machined by a material-removing machining tool with these data the track component that a the

Reference wheel profile same wheel profile on the track component describes a trajectory that corresponds to the desired trajectory.

2. Device for profiling an overflow geometry of track components according to claim 1, characterized in that - a measuring system determines the course of a trajectory of a wheel provided with a reference wheel profile when rolling over the respective track component in a spatially fixed coordinate system and evaluated by means of a data processing system with regard to its dynamic effects, a data processing system determines an optimized target trajectory based on the measured trajectory, which can be achieved within the framework of tolerable material removal by the track component,

a material-removing machining tool is shaped in such a way that, during machining of the track component, it removes the material in a shape matching a given wheel profile, so that the machining tool is supported within a framework serving as reference frame. Siseinheit is guided in a spatially fixed coordinate system on the track component, that it follows during the material-removing machining of the determined target trajectory.

3. A device for profiling an overflow geometry of track components according to claim 2, characterized in that the machining tool is a milling machine.