DE29810998U1

DE29810998U1 - Combined sensor system for continuous control of the wheel sets of rail vehicles for mechanical defects and faulty wheel arches, as well as detection of dangerous driving conditions

Info

Publication number: DE29810998U1
Application number: DE29810998U
Authority: DE
Original assignee: Individual
Current assignee: Individual
Priority date: 1998-06-05
Filing date: 1998-06-19
Publication date: 1999-01-07
Anticipated expiration: 2008-06-20

Description

GebrauchsmusteranmeldungUtility model application

Kombiniertes Sensorsystem zur kontinuierlichen Kontrolle der Radsätze vonCombined sensor system for continuous monitoring of the wheel sets of

Schienenfahrzeugen auf mechanische Defekte und fehlerhaften Radlauf,Rail vehicles for mechanical defects and faulty wheel running,

sowie Detektion von gefährlichen Fahrzuständen.and detection of dangerous driving conditions.

Wie sich bei einem Unfall herausstellte, fahren Schienenfahrzeuge, insbesondere die Hochgeschwindigkeitszüge, trotz teilweise aufwendiger Sicherheitseinrichtungen ohne ein Kontrollsystem, welches Radschäden detektiert und Entgleisungen einzelner Radsätze bzw. ganzer Drehgestelle erkennt. Um diesen Sachverhalt zu verbessern, wird ein kombiniertes Sensorsystem, einschließlich Sicherheits-Datenkommunikationseinrichtung beschrieben, welches die Erfassung und Verteilung wichtiger Sicherheits- und Radlaufdaten ermöglicht. Innerhalb des Sensorsystems wird ein Wirbelstrom- / Magnetfeldsensor beschrieben, welcher während der Fahrt Risse und Beschädigungen am Radreifen erkennt.As was revealed in an accident, rail vehicles, especially high-speed trains, travel without a control system that detects wheel damage and recognizes derailments of individual wheel sets or entire bogies, despite sometimes complex safety equipment. In order to improve this situation, a combined sensor system, including a safety data communication device, is described, which enables the recording and distribution of important safety and wheel running data. An eddy current / magnetic field sensor is described within the sensor system, which detects cracks and damage to the wheel tire during travel.

Die besondere Stärke des beschriebenen Systems, liegt in der Kombination unterschiedlicher Sensortypen zu einer in sich geschlossenen Sicherheitseinrichtung, welche die wichtigsten und gefährlichsten Raddefekte und Störungen der Fahrdynamik erkennt, noch bevor ein gefährlicher Störfall eintritt.The particular strength of the system described lies in the combination of different sensor types to form a self-contained safety device, which detects the most important and dangerous wheel defects and disturbances to driving dynamics before a dangerous malfunction occurs.

Bisher bekannte Schutzeinrichtungen überprüfen lediglich die Temperatur der Radlager mit Temperaturfühlern oder Infrarotsensoren, Verschleiß oder Defekte der Radlager durch Körperschallsensoren, sowie das Vorhandensein der Radreifen durch Magnetschalter oder Lichtschranken. Weiterhin werden mechanische Fühler und Schalter zur Erkennung von Defekten und mechanischer Abnutzung eingesetzt.Previously known protective devices only check the temperature of the wheel bearings with temperature sensors or infrared sensors, wear or defects in the wheel bearings with structure-borne sound sensors, and the presence of the wheel tires with magnetic switches or light barriers. Mechanical sensors and switches are also used to detect defects and mechanical wear.

In stationären Wartungseinrichtungen werden die Radscheiben und Radreifen mittels Ultraschalluntersuchungen auf Risse und Schäden kontrolliert. Analog hierzu, ist die ebenfalls stationäre Kontrolle der Radscheiben mittels Wirbelstromdetektion innerhalb der Vorsorgeuntersuchungen geplant. Im Gegensatz zu dem nachfolgend beschriebenen Verfahren, wird hierbei die Radscheibe mit einem starken Gleich-Magnetfeld solcher Feldstärke beaufschlagt, daß die Radscheibe partiell magnetisch gesättigt ist. Die Wirbelströme, in der sich sehr langsam drehenden Radscheibe, werden mittels eines dem magnetischen Gieichfeld überlagerten magnetischen Wechselfeldes ebenfalls großer Feldstärke erzeugt. Dieses Verfahren, welches Schäden bis ca. 10 mm Tiefe erkennt, ist jedoch für mobile Anwendung während der Fahrt nicht geeignet.In stationary maintenance facilities, the wheel disks and wheel tires are checked for cracks and damage using ultrasound examinations. Similarly, the stationary inspection of the wheel disks using eddy current detection is planned as part of the preventive examinations. In contrast to the method described below, the wheel disk is exposed to a strong DC magnetic field of such a field strength that the wheel disk is partially magnetically saturated. The eddy currents in the very slowly rotating wheel disk are generated by an alternating magnetic field of a high field strength superimposed on the DC magnetic field. This method, which detects damage up to a depth of approx. 10 mm, is not suitable for mobile use while driving.

Der Vorteil der nachfolgend beschriebenen Einrichtung gegenüber bisherigen mobilen Verfahren, welche lediglich das Vorhandensein des Radreifens oder den bereits erfolgten Radbruch erkennen, liegt in der Detektion von Materialfehlern oder Defekten bereits in der Entstehungsphase, noch bevor z.B. der Radreifen bricht. Das System erhöht dadurch sowohl die Betriebssicherheit, als auch die Verfügbarkeit der damit ausgerüsteten Zugeinheiten, wobei gleichzeitig die Betriebs- und Wartungskosten vermindert werden.The advantage of the device described below compared to previous mobile methods, which only detect the presence of the wheel tire or the wheel breakage that has already occurred, lies in the detection of material defects or faults in the development phase, before the wheel tire breaks, for example. The system therefore increases both the operational safety and the availability of the tractor units equipped with it, while at the same time reducing operating and maintenance costs.

1. Detektion von Materialdefekten und Haarrissen1. Detection of material defects and hairline cracks

1.1 Die Radreifen (Pos. 4) werden während der Fahrt mittels Wirbelstromsensoren bzw. Magnetfeldsensoren (Pos. 7, Pos. 10.1-5) auf Bruch und Risse überprüft. Diese Überprüfung geschieht kontinuierlich, auch bei hohen Fahrgeschwindigkeiten. Hierbei wird das einzelne Rad (Pos. 3/4) partiell von einem Magnetfeld beeinflußt, welches von einem1.1 The wheel tires (item 4) are checked for breakage and cracks during the journey using eddy current sensors or magnetic field sensors (item 7, items 10.1-5). This check is carried out continuously, even at high driving speeds. Here, the individual wheel (item 3/4) is partially influenced by a magnetic field, which is generated by a

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nahe dem Radreifen (Pos. A) montierten Wirbelstrom-Magnetfeldsensor erzeugt wird. Wenn sich das Rad dreht, werden die äußeren Radsegmente (Pos. 4) fortlaufend von dem Magnetfeld des Sensors (Pos. 7, Pos. 10.1-5) durchflossen, wodurch sich im entsprechenden Bereich Wirbelströme ausbilden. Bei intaktem Radreifen (Pos. 4) wandert dieser Bereich der magnetischen Beeinflussung und der Ausbildung von Wirbelströmen entsprechend der Raddrehung gleichmäßig um den kpl. Radumfang. Wenn nun Haarrisse oder auch größere Schäden am Radreifen entstehen, wird an diesen Stellen sowohl der Magnetfluß, als auch die Ausbildung von Wirbelströmen gestört. Diese Störung wird von einem Sensor, bestehend aus einer Spule oder einem Linear-Hallgenerator erfaßt und in einer Auswerteeinheit mit nachgeschaltetem Computer analysiert.is generated by an eddy current magnetic field sensor mounted near the wheel rim (item A) . When the wheel rotates, the magnetic field of the sensor (item 7, items 10.1-5) continuously flows through the outer wheel segments (item 4), causing eddy currents to form in the corresponding area. If the wheel rim (item 4) is intact, this area of magnetic influence and the formation of eddy currents moves evenly around the entire circumference of the wheel in accordance with the wheel rotation. If hairline cracks or major damage occur on the wheel rim, both the magnetic flux and the formation of eddy currents are disrupted at these points. This disruption is detected by a sensor consisting of a coil or a linear Hall generator and analyzed in an evaluation unit with a downstream computer.

1.2 Defekte der Radlager (Pos. 5) werden von Körperschallsensoren (Pos. 6) mit nachgeschalteter Signalverarbeitung aufgespürt. Hierbei werden die Lagergeräusche kontinuierlich analysiert und mit den charakteristischen Signalen des neuen Lagers verglichen. Die Signalanalyse erfolgt in der spektralen Frequenzverteilung und dem Amplitudenverlauf der vom Lager verursachten Schwingungen und Körpergeräusche. Wenn das Lager einen bestimmten Abnutzungsgrad überschreitet, oder einen Akutschaden aufweist, erhöhen, bzw. verändern sich die typischen Lagergeräusche, was von der Signalauswerteeinrichtung erkannt und dem Lokführer angezeigt wird. Dieses bekannte Verfahren wird um neue Komponenten in der Signalauswertung ergänzt, wodurch zusätzlich das Laufverhalten des Rades, sowie der korrekte Schienenkontakt (Pos. 1/4) detektiert werden kann.1.2 Defects in the wheel bearings (item 5) are detected by structure-borne noise sensors (item 6) with downstream signal processing. The bearing noises are continuously analyzed and compared with the characteristic signals of the new bearing. The signal analysis is carried out in the spectral frequency distribution and the amplitude curve of the vibrations and structure-borne noises caused by the bearing. If the bearing exceeds a certain degree of wear or has acute damage, the typical bearing noises increase or change, which is recognized by the signal evaluation device and displayed to the train driver. This well-known process is supplemented by new components in the signal evaluation, whereby the running behavior of the wheel and the correct rail contact (item 1/4) can also be detected.

1.3 Die Radlager-Temperaturen (Pos. 5) werden gemäß bekanntem Verfahren durch jeweils einen Temperatursensor pro Radlager gemessen.1.3 The wheel bearing temperatures (item 5) are measured according to a known method by one temperature sensor per wheel bearing.

1.4 Der Zusammenhalt des Zugverbundes wird gemäß bekanntem Verfahren durch das Auswerten der Daten, einer den ganzen Zug durchlaufenden Daten-Ringleitung ermittelt. Hierbei wird eine Datenleitung von der ziehenden Lokomotive durch alle Wagen bis zur schiebenden Lokomotive oder den letzten Wagen geschleift. An diesen Datenbus sind alle Wagen und Lokomotiven durch jeweils ein Wagenkontrollgerät angeschlossen, welches die Elektronik für die Signalanalyse und Signalauswertung der Sensoren beinhaltet. Mittels einer Funkverbindung vom letzten Wagen bzw. der hinteren Lokomotive zur ziehenden Lokomotive wird der Datenring geschlossen. Wenn nun der Zugverbund und damit die Datenringleitung durch einen Unfall oder technischen Defekt unterbrochen wird, erkennt das System dies durch das Ausbleiben der entsprechenden Sensordaten. Die Funkverbindung sichert in diesem Fall die Datenverbindung zum Zugende und dem verbleibenden hinteren Zugabschnitt. Weiterhin können vom Lokführer über diese Funkverbindung Steuer- und Bremsbefehle zum Zugende übermittelt werden.1.4 The cohesion of the train is determined according to a known method by evaluating the data from a data loop that runs through the entire train. A data line is looped from the pulling locomotive through all the cars to the pushing locomotive or the last car. All cars and locomotives are connected to this data bus by a car control device, which contains the electronics for signal analysis and signal evaluation from the sensors. The data loop is closed by means of a radio connection from the last car or the rear locomotive to the pulling locomotive. If the train and thus the data loop is interrupted by an accident or technical defect, the system recognizes this by the absence of the corresponding sensor data. In this case, the radio connection ensures the data connection to the end of the train and the remaining rear section of the train. The driver can also use this radio connection to transmit control and braking commands to the end of the train.

2. Erschütterungen bei Entgleisungen2. Vibrations during derailments

2.1 Die am Radlager (Pos. 5) montierten Körperschallsensoren (Pos. 6) erfassen zusätzlich zu den Lagergeräuschen bzw. Lagerschäden natürlich auch die Erschütterungen und den Körperschall welcher entsteht, wenn das Rad entgleist und über das Schotterbett oder die Schwellen rollt. Diese Signale werden von der Auswerteelektronik ausgewertet und das Ergebnis zum Lokführer weitergeleitet. Die Auswerteelektronik enthält spezielle Computerprogramme und Routinen, welche das Sensorsignal auf korrekten Radlauf, sowie korrekten Schienenkontakt untersucht.2.1 The structure-borne noise sensors (item 6) mounted on the wheel bearing (item 5) record in addition to the bearing noise or bearing damage, of course also the vibrations and the structure-borne noise that occurs when the wheel derails and rolls over the ballast bed or the sleepers. These signals are evaluated by the evaluation electronics and the result is passed on to the train driver. The evaluation electronics contain special computer programs and routines that examine the sensor signal for correct wheel alignment and correct rail contact.

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2.2 Die im Wagenaufbau über den Drehgestellen montierten Beschleunigungssensoren erfassen die mechanische Beschleunigung in allen drei Achsen. Damit werden die Erschütterungen und Stöße erfaßt, welche entstehen, wenn das Fahrzeug entgleist und über das Schotterbett oder die Schwellen rollt. Diese Signale werden ausgewertet und zur Störungsunterdrückung mit den Daten nach 2.1 verglichen.2.2 The acceleration sensors mounted in the car body above the bogies record the mechanical acceleration in all three axles. This records the vibrations and shocks that occur when the vehicle derails and rolls over the ballast bed or sleepers. These signals are evaluated and compared with the data in 2.1 to suppress interference.

3. Längs- und Querbeschleunigung - Schlingerbewegung 3. Longitudinal and lateral acceleration - rolling motion

3.1 Die im Wagenaufbau über den Drehgestellen montierten Beschleunigungssensoren erfassen alle Schaukel- und Schlingerbewegungen jedes einzelnen Fahrzeuges. Durch die Auswertung dieser Daten, kann das gefährliche Aufschaukeln des Wagenaufbaus noch im Entstehungsstadium erkannt werden. Somit kann der Zugführer durch das rechtzeitige Einleiten von Gegenmaßnahmen, z.B. leichtes Bremsen, die Situation leicht entschärfen, noch bevor eine bedrohliche Situation eintritt. Weiterhin wird der Komfort der Fahrgäste durch die Verhinderung unkontrollierter Wagenbewegungen erheblich gesteigert, was die Akzeptanz des entsprechend ausgerüsteten Schienenfahrzeuges erheblich verbessert.3.1 The acceleration sensors mounted in the car body above the bogies record all rocking and swaying movements of each individual vehicle. By evaluating this data, dangerous rocking of the car body can be detected as it begins. The train driver can therefore easily defuse the situation by initiating countermeasures in good time, e.g. light braking, before a threatening situation occurs. Furthermore, the comfort of the passengers is significantly increased by preventing uncontrolled car movements, which significantly improves the acceptance of the appropriately equipped rail vehicle.

4. Schienenkontakt - Radlauf4. Rail contact - wheel arch

4.1 Der korrekte Radlauf wird mittels eines Radar-Dopplersensors (Pos. 8) überprüft. Dies geschieht kontinuierlich auch bei den Höchstgeschwindigkeiten des Zuges. Hierzu ist ein Radar-Dopplersensor (Pos. 8) so über dem Gleis angeordnet, daß der gebündelte Strahl (Pos. 9) auf die Lauffläche des Schienenprofils (Pos. 1) strahlt. Der Radar-Dopplersensor sendet ein kontinuierliches Hochfrequenzsignal auf die Schienenlauffläche. Das vom Gleis (Pos. 1) reflektierte Signal ist gemäß dem Dopplereffekt Frequenz- und Phasenverschoben. Dieses Signal wird im Radar-Dopplersensor mit dem Sendesignal gemischt, wobei ein Niederfrequenzsignal entsteht, welches die geometrische Beschaffenheit der abgetasteten Oberfläche widerspiegelt. Wird das Hochfrequenzsignal gepulst, kann zusätzlich zu den im Dopplersignal enthaltenen Informationen aus der Signallaufzeit der Abstand zwischen Sensor und Gleisoberfläche ermittelt werden. Solange die Radachse korrekt auf den Schienen läuft, wird das von der Schiene reflektierte Signal, welches gemäß dem Dopplereffekt nur minimale Frequenzsprünge aufweist, von dem Sensor empfangen und ausgewertet. In diesem Falle ist die Frequenzverschiebung kontinuierlich gleichmäßig. Lediglich beim Überfahren von Weichen und Dehnungsfugen tritt eine kurzzeitige sprunghafte Frequenzverschiebung auf, welche vom System erkannt und ausgeblendet wird. Im Falle der Entgleisung einer Radachse oder des kpl. Drehgestelles befindet sich der Sensor nicht mehr korrekt über der Schienenlauffläche. Dadurch strahlt der Radar-Dopplersensor entweder auf das Kiesbett, auf die Schwellen oder leicht am Schienenkopf vorbei auf die Befestigungsschrauben. In diesen Fällen ist das reflektierte Signal jedoch mit entsprechenden Frequenz- und Phasensprüngen behaftet. Diese hochfrequenten Frequenz- und Phasensprünge werden im Dopplersensor in ein Niederfrequenzsignal umgewandelt und der Auswerteelektronik, welche Bestandteil des Wagenkontrollgerätes ist, übermittelt. Hier wird das Signal mit den Soll- und Toleranzdaten verglichen und bei Überschreitung der Toleranzen das Entgleisungs-Alarmsignal generiert.4.1 The correct wheel alignment is checked using a radar Doppler sensor (item 8). This is done continuously, even at the train's maximum speed. For this purpose, a radar Doppler sensor (item 8) is arranged above the track so that the bundled beam (item 9) shines onto the running surface of the rail profile (item 1). The radar Doppler sensor sends a continuous high-frequency signal onto the rail running surface. The signal reflected from the track (item 1) is frequency and phase shifted according to the Doppler effect. This signal is mixed with the transmission signal in the radar Doppler sensor, creating a low-frequency signal that reflects the geometric nature of the surface being scanned. If the high-frequency signal is pulsed, the distance between the sensor and the track surface can be determined from the signal runtime in addition to the information contained in the Doppler signal. As long as the wheel axle is running correctly on the rails, the signal reflected from the rail, which has only minimal frequency jumps due to the Doppler effect, is received and evaluated by the sensor. In this case, the frequency shift is continuously even. Only when crossing switches and expansion joints does a short-term, sudden frequency shift occur, which is detected and ignored by the system. If a wheel axle or the entire bogie derails, the sensor is no longer correctly positioned above the rail surface. As a result, the radar Doppler sensor either shines onto the gravel bed, onto the sleepers, or slightly past the rail head onto the fastening screws. In these cases, however, the reflected signal is subject to corresponding frequency and phase jumps. These high-frequency frequency and phase jumps are converted into a low-frequency signal in the Doppler sensor and transmitted to the evaluation electronics, which is part of the wagon control device. Here the signal is compared with the target and tolerance data and if the tolerances are exceeded the derailment alarm signal is generated.

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Claims

Protection claims

1. Combined sensor system for continuous monitoring of the wheel sets for mechanical defects and correct rail contact. Characterized in that each wheel (item 3) is checked for mechanical defects in the wheel tire (item 4) using an eddy current or magnetic field sensor and each wheel set or bogie (item 2) is checked for correct wheel alignment using a radar Doppler sensor (item 8). Furthermore, characterized in that each wheel bearing (item 5) is monitored for bearing defects and unacceptable running noises and vibrations using a structure-borne sound sensor (item 6). A three-dimensional acceleration sensor installed in each car detects vibrations as well as longitudinal and transverse accelerations to which the car bodies are exposed.

2. Device according to protection claim 1, characterized in that the eddy current sensor / magnetic field sensor (item 7) consists of a U-shaped iron core, on which two separate wire windings are applied. A direct current flows through winding A, which generates a magnetic field that acts on the wheel tire. Winding B represents the sensor winding, which detects the magnetic flux changes caused by wheel defects (cracks, breaks in the wheel tire). The U-shaped iron core with the wire windings is mounted so close to the wheel tire (item 4) that the sensor exerts a magnetic influence on the wheel and the magnetic field that penetrates the outer wheel tire is detected. The sensor winding is connected to signal evaluation electronics.

3. Device according to protection claim 1, characterized in that the eddy current sensor / magnetic field sensor (Fig. 2) consists of an electromagnet with a U-shaped iron core (item 10.1) and a mechanically and magnetically separated sensor winding (item 10.5), also with a U-shaped iron core (item 10.4). The sensor winding is arranged together with its iron core within the legs of the U-shaped electromagnet. The sensor winding including the iron core is magnetically shielded from the electromagnet by a shielding hood made of mu-metal (item 10.3) and can only be magnetically excited via the two poles of the iron core, which are arranged near the wheel tire (item 4). Direct current flows through the winding of the electromagnet (item 10.2), which generates a magnetic field that acts on the wheel tire. The sensor winding detects the magnetic field changes caused by wheel defects (cracks, breakouts in the wheel tire). The electromagnet with the internal sensor winding is mounted so close to the wheel tire that the sensor has a magnetic influence on the wheel and the magnetic field that penetrates the outer wheel tire can be detected. The sensor winding is connected to signal evaluation electronics.

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■ · * ··■ · * ·· • · · ·· · · » · · ·» · · ·
»&phgr; &phgr; · · ·»φ φ · · · • · · ·· · ·

4. Device according to protection claim 3, characterized in that the sensor winding is replaced by a magnet-sensitive semiconductor component, a so-called Hall linear probe. The Hall linear sensor is arranged within the legs of the U-shaped electromagnet and is magnetically shielded from the electromagnet by a shielding hood made of mu-metal. Magnetic influence can only occur via the opening of the shield facing the wheel. Direct current flows through the winding of the U-shaped electromagnet, creating a magnetic field that acts on the wheel tire. The Hall linear probe detects the magnetic field changes caused by wheel defects (cracks, breakouts in the wheel tire). The electromagnet with the internal Hall linear probe is mounted so close to the wheel tire that the sensor has a magnetic influence on the wheel and the magnetic field that penetrates the outer wheel tire can be detected. The signal output of the Hall linear probe is connected to an evaluation electronics.

5. Device according to claim 4, characterized in that a different number of Hall linear sensors are arranged inside and outside the electromagnet. In this version, for example, several Hall linear sensors are used at a distance of 5 mm across the entire wheel width.

6. Device according to claims 2 to 5, characterized in that the magnetic field sensors are equipped with a demagnetizing device. This consists of a switching device which is designed in such a way that an alternating current source can be connected to the excitation winding of the electromagnet. Furthermore, dirt scraper plates are arranged on the sensor in such a way that the deposits which settle on the wheel ring are scraped off.

7. Device according to claims 1 to 5, characterized in that alternating current flows through the excitation winding of the magnetic field sensor. The open gap of the U-shaped iron core is arranged so close to the wheel (item 4) that the changing magnetic field caused by the current flow can act on the wheel tire. The sensor windings or the Hall generators are dimensioned in such a way that the magnetic flux changes caused by wheel defects are detected. The sensor windings or the Hall sensors are connected to an evaluation electronics. This evaluation electronics is designed in such a way that the signals detected by the sensor windings or the Hall generators can be analyzed in terms of amplitude and time.

8. Device according to claims 2 to 7, characterized in that the holder of the magnetic field sensor is provided with a distance adjustment device. This adjustment device is designed so that the mechanical distance of the magnetic field exciter and the sensor to the wheel tire can be changed manually.

9. Device according to claim 8, characterized in that the distance adjustment device of the magnetic field sensor to the wheel tire is provided with a motor-driven adjustment device. The electric drive motor is connected to control electronics. Furthermore, a mechanical distance sensing device or alternatively an ultrasonic distance measuring device is connected to this control electronics. The sensing device or the ultrasonic sensor are designed or arranged in such a way that the distance of the magnetic field sensor to the wheel tire can be determined.

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10. Device according to claim 1, characterized in that a structure-borne sound sensor (item 6) is attached to each wheel bearing (item 5). This structure-borne sound sensor is designed for the frequency range from 0 Hz to approx. 20 Khz. The arrangement and mechanical coupling of the structure-borne sound sensor to the wheel bearing is done in such a way that both the vibrations generated by the wheel bearing and the running noises that arise between the wheel and the rail are detected.

11. Device according to protection claim 10, characterized in that the structure-borne sound sensor (item 6) is provided with an evaluation electronics. This evaluation electronics is designed in such a way that wheel running noises caused by derailment or by mechanical damage or imbalance can be detected.

12. Device according to claims 10 and 11, characterized in that the signal outputs of the structure-borne sound sensors (item 6) are connected to an evaluation electronics. This electronics is equipped with devices for analyzing the spectral frequency distribution as well as the analysis of the amplitude curve. Furthermore, an alarm forwarding is included. The evaluation electronics can be a component of the vehicle control device or can be assigned to the structure-borne sound sensor as individual electronics.

13. Device according to protection claim 1, characterized in that at least one radar Doppler sensor (item 8) is installed on each bogie (item 2) or wheel set of the train. The radar Doppler sensor is designed so that it can detect the distance and the relative spatial arrangement of the wheel (item 4) to the rail running surface. For this purpose, the sensor is mounted above the track on the bogie or axle and adjusted so that the tightly focused high-frequency radiation from the sensor hits the rail running surface (item 1) exactly. The expansion of the focused high-frequency radiation must be such that the sensor immediately radiates past the rail head onto the sleepers or the track fastening screws as soon as the wheel does not roll correctly on the track or jumps off the track. The radar Doppler sensor has a high-frequency receiver which receives the Doppler signal reflected from the rail head or the sleepers. The receiver output signal socket is connected to the evaluation electronics, which is part of the vehicle control device.

14. Device according to claim 1, characterized in that one or two three-dimensional acceleration sensors are mounted in each car body above the bogies or wheels. The sensors are designed and mounted in such a way that the centrifugal forces, shocks and vibrations to which the car body is exposed are detected in all three dimensions. The three output signals of the acceleration sensors are fed via cables to the central car control device with evaluation electronics. Optionally, the three-dimensional acceleration sensor can also be installed directly in the car control device (claim 15).

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15. Device according to claim 1, characterized in that the signals detected by the sensors according to claims 2 to 14 are fed to a central wagon control device by means of a coaxial cable or optical fiber. The wagon control device, which is present in each wagon or locomotive, contains the evaluation electronics consisting of a spectrum analyzer for the structure-borne sound sensors, as well as the evaluation electronics for the eddy current sensors, the radar Doppler sensors and the acceleration sensors. All wagon control devices of a train are connected to one another by a data line (ring line). A computer is also integrated, which contains a signal analysis device and the locomotive driver alarm message generation. A device is optionally available which triggers the emergency brake signal.

16. Device according to claim 15, characterized in that the wagon control devices installed in the locomotives have a control keyboard and a data display. They also have a radio connection, which allows direct data communication between the two locomotives or between the pulling locomotive and the last wagon.

17. Device according to claims 1 to 16, characterized in that all sensor signal outputs of the individual axles or bogies are connected to a signal collection electronics with a time multiplex device. This multiplex electronics is connected to the evaluation electronics in the wagon control device by means of a data line.

18. Device according to claims 10, 11 and 12, characterized in that the structure-borne sound sensor (item 6) mounted on the wheel bearing (item 5) is mechanically and functionally combined with the signal processing electronics. The structure-borne sound sensor and the evaluation electronics can be mounted in separate housings or in a common housing. The signal processing electronics consist of a spectrum analyzer, an analog-digital converter, a control computer and output electronics.

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