TRAIN INTEGRITY MONITORING DEVICE

Abstract: A train integrity monitoring device for detecting operating parameters of a train, especially concerning a brake system used in the train, includes a sensor means (6). Output signals of the sensor are supplied to a control means (7) for processing and forming information regarding the train integrity. When evaluating the sensor output signals, the control means (7) compares detected operating parameters with predetermined values of the respective operating parameters for a corresponding operating condition of the train, and the integrity of the train is inferred in response to the result of comparison.

Description: TRAIN INTEGRITY MONITORING DEVICE BACKGROUND OF THE INVENTION This application relates generally to a train integrity monitoring device and, in particular, to a monitoring device for detecting the integrity of a railroad train with consideration of operating parameters of the cars of the train. Important parts of equipment of a railroad train (hereinafter simply referred to as train) include the brake system with the pertinent control, as, when the train loads and the running speed of the trains are increased, higher requirements are to be made for the safe function of the brake system. The detection and monitoring of the integrity of the train is in close connection with the monitoring of the brake system, because both an interference of the brake system and an undesired separation of the train (undesired separation of at least one car from the rest of the train) may entail considerable troubles and dangerous operating situations. In a compressed air brake used in modern railroad systems a compressor means for generating compressed air is provided on an engine (locomotive) for conveying the train, and all cars are connected via a continuous air pipe, the so-called brake pipe. Between the individual cars of the train an appropriate connection of the brake pipe is provided, apart from the mechanical coupling, to transfer the tractive forces. When the brake is actuated, the air pressure in the brake pipe is lowered to generate a brake force by the individual wheel brakes of each car. For releasing the brake the air pressure of the brake pipe has to be appropriately increased again. The instruction to actuate the brakes (braking operation) or to release the brakes is output at one location in the train, usually in the engine or in an adequately equipped control car, wherein the brake can basically be activated at any suitable location in the train, when the air pressure in the brake pipe is lowered ("emergency brake"). If an undesired separation of the train occurs when the train is running, likewise the compressed air couplings of the brake pipe between the respective cars are opened, whereupon the air pressure in the brake pipe suddenly drops. The rapid drop of the air pressure in the brake pipe causes a rapid stop in all cars similarly to the emergency stop. Apart from this initiation of a rapid stop due to the brake system in the case of undesired separation of the train, it is necessary to detect and monitor the integrity of the train also in a different way. From the German magazine: R. Heitmann,, R. Ptok, "Systeme zur Zugvollstaendigkeitserfassung" (Systems for train integrity monitoring), Signal + Draht (89) 1 1 , 97, a system for train integrity monitoring is known in which predetermined operating parameters of the train are detected and monitored. In detail the monitoring relates to the operating parameters of the brake such as the pressure of the compressed air of the brake and the amounts of air flowing in the brake system. For detecting and evaluating the operating parameters appropriate means connected to each other for the transmission of data are provided at both ends of the train. In Figure 2 such an arrangement is illustrated, wherein in an engine 1 including coupled cars 2 and 3 (last car) a compressor 4 is provided for supplying a brake pipe 5 passing through the entire train with compressed air. A monitoring means 6 arranged at the last car 3 of the train detects the air pressure of the brake pipe 5 and transmits a corresponding information concerning the data detected to a control means 7 arranged in the engine 1 for evaluation of the data and display of any irregularities or troubles. The control means 7 in the engine 1 in detail evaluates the detected actions of the engineer, the data formed in the engine itself as well as the data detected and transmitted by the monitoring means 6 at the end of the train. A wireless transmission in the form of an ultrasonic transmission or radio transmission is provided in the present prior art for transmitting the data from the monitoring means 6 at the end of the train to the control means 7 in the engine 1. For a complete communication between the monitoring means 6 at the end of the train and the control means 7 in the engine 1 transmitters and receivers corresponding to the selected transmission mode are provided at the end of the train and in the engine. At least, however, in the monitoring means 7 a transmitter is provided and a receiver is provided in the engine 1. The use of a mutual radio communication between the engine 1 and the monitoring means 6 at the last car 3, however, is highly susceptible to interferences, especially if such a device is operated on tunnel lines and, in particular, on curved track tunnel lines. In accordance with the above-mentioned prior art, a line connection may be provided for data transmission from the monitoring means 6 at the end of the train to the control means 7 in the engine 1, the data transmission being effected by means of the usually multipolar transmission line (UIC line). A transmission system of this kind is not subjected to the interferences occurring in radio or ultrasonic links, but particular problems may arise at the link couplings of the lines between the individual cars, when the couplings have to be frequently disconnected and the contact safety of the multipolar line is impaired by dirt accumulation. Furthermore it is also suggested to use a glass-fiber cable passing through the entire train for data transmission, wherein, however, apart from the principal immunity to interfering of this system, problems may arise at the junction points between the individual cars in the same way as when using the multipolar line. Fiber-optical light guides can only be employed in a reasonable manner, if the predetermined train connection consisting of a plurality of cars is not or only very rarely separated, as in this case a dirt accumulation at the junction points is largely avoided (use in the case of ICE motor-coach trains of the Deutsche Bahn AG). In this case the multipolar line or the glass-fiber connection also serves as data bus of the entire train. However, the use of the monitoring means 6 at the end of the train requires the possibility of supplying electric power to the monitoring means 6 to safeguard a continuous operation. In the case of passenger cars an electric power supply is usually provided, because each car is supplied with electric power for lighting and heating from the engine by means of a bus bar passing through the entire train. This electric power supply can be used for feeding the monitoring means 6 disposed at the end of the train. Moreover a lot of passenger trains are run with cars in a fixed connection, the individual cars being separated from each other very seldom. The same applies to the passenger train operation with motor-coach trains so that in this case the use of data lines in the form of electric lines or glass-fiber connections presents itself. If, however, freight trains are likewise to be included in the train integrity monitoring, then it is not possible to monitor the train integrity by means of continuous electric lines or glass-fiber connections, because freight cars are not equipped with the appropriate means and are used unrestrictedly in constantly changing trains. Furthermore freight cars are not equipped with an electric power supply, as in normal operation only passenger cars include a power supply via the bus bar of the train or are equipped with an inherent power supply by a generator and a battery. If thus a freight train is included in the train integrity monitoring, it is necessary, according to prior art, to dispose the respective monitoring means at the end of the train and furthermore to provide a reliable electric power supply for the monitoring means. The detection of data for train integrity monitoring including means arranged at the front and rear train ends thus requires considerable expenditure on technical equipment. Furthermore it has to be observed with an unrestricted change of freight cars between different trains usual in the case of freight cars, whether the last freight car includes a monitoring means for train integrity monitoring and that the monitoring means 6 is removed or switched off, if the respective freight car is no longer connected as the last car in a new train system. Thus logistics are required for providing the respective monitoring means, for the maintenance and care of the monitoring means and for a reasonable use of the monitoring means in the respective freight train. Apart from the means for train integrity monitoring disposed in the train itself, there are provided stationary monitoring means in the form of axle counters here and there along particular portions of lines, which count the axles of a passing train and supply a corresponding information to a central control terminal. Stationary axle counters of this kind are only adapted to monitor the train integrity at particular locations in the line network of a railroad company so that, apart from considerable expenditure on equipment, the low flexibility of such means represents a drawback. BRIEF SUMMARY OF THE INVENTION In one embodiment of the invention, safe train integrity monitoring is ensured in a simple manner with a considerably reduced expenditure on technical equipment even in the case of optionally composed trains and independently of the cars used in the train. In an exemplary embodiment, at least one sensor means is provided in the train integrity monitoring means for detecting operating parameters of the cars involved such as the engine and the coupled passenger or freight cars. The sensor means is linked to the control means for transmitting the information generated by the sensor means to the control means. The control means executes the integrity monitoring of the train, the operating parameters detected by the sensor means being compared to predetermined values of such operating parameters and the integrity of the train being inferred in response to the result of comparison. The monitoring means and the detection of the operating parameters of the cars involved are provided exclusively at one end of the train, preferably in the engine at the front end of the train, so that the expenditure on technical equipment is considerably reduced, as no monitoring means in connection with transmitting and receiving means is necessary at the end of the train. The operating parameters detected by the sensor means are evaluated relative to predetermined values of such operating parameters so that a particular condition of the brake system of the train can be inferred from the comparison of the predetermined values with the currently measured values, on the basis of which furthermore the train integrity is determined. In this way a high safety level for the train integrity monitoring is guaranteed while simultaneously a simple handling and a low expenditure on equipment are ensured. The device according to the invention can be used in any cars, if the respective sensors and the control means are arranged centrally in one car. The device according to the invention works reliable and the accuracy of detection is not deteriorated by deteriorated radio links or by impairments of a radio or ultrasonic link in a tunnel. Moreover the unrestricted use of the cars is guaranteed irrespective of whether passenger cars or freight cars are concerned. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 shows an arrangement of a train including a train integrity monitoring device disposed at one end of the train; and Figure 2 shows a train arrangement including a train integrity monitoring device distributed to both ends of the train in accordance with prior art. DETAILED DESCRIPTION OF THE INVENTION Figure 1 shows a train arrangement in which the train integrity monitoring device is used. Parts of the same kind are denoted with the same reference numerals in Figure 1 and in Figure 2. A brake pipe 5 is filled with compressed air by means of a compressor 4 disposed in an engine 1. The brake pipe 5 passes through the entire train from the engine 1 via coupled cars 2 to a last car 3. In the engine 1 further a sensor means 6 serving as monitoring means is provided as well as a control means 7 which is connected with the sensor means 6 and which receives and processes the data supplied by the sensor means 6. Thus the entire train integrity monitoring device is disposed in one car of the train, preferably in the engine 1 as the first car, so that corresponding additional means such as further sensors at locations in the train, i.e. in other cars, can be dispensed with. In this way also the problem especially in the case of freight cars which are not equipped with an independent power supply to provide a separate power supply assigned to the respective sensor or monitoring means does not arise. The control means 7 arranged in the engine 1 performs the integrity monitoring for the train on the basis of the sensor signals supplied by the sensor means 6 via the operating parameters of the engine 1 and the entire train. In detail, the control means 7 processes, on the basis of the information supplied by the sensor means 6, all measures of the engineer such as, e.g., filling up the brake pipe 5 of the brake system of the train with compressed air, releasing the brake, various braking operations to decelerate the train or to further reduce the speed until the train stops, the driving speed of the train and the number of the coupled cars 2, 3. When detecting the operating parameters, especially of the brake system of the train, the air pressure prevailing in the brake pipe 5, the air volume required for the entire train to release the brake, the air loss rate due to inevitable leakages of the brake system (especially of the compressed air couplings for connecting the brake pipe between the individual cars), the braking instructions given by the engineer and the respective times for lowering or increasing the air pressure of the brake pipe are detected. The operating parameters of the train detected during the stop or the ride of the train, especially the operating parameters of the brake system, are compared to predetermined values of such operating parameters with respect to an evaluation for obtaining an information about the train integrity. The magnitude of deviations established from the comparison of the respective actually measured operating parameters of a particular operating condition to the predetermined values of such operating parameters of the same operating condition permits a statement about whether an undesired train separation, an interference of operation (impairment of operation) or a normal operation (trouble-free operation) is provided. A separation of the train causes, for instance, a break of the compressed air couplings of the brake pipe between the cars so that the air pressure of the brake pipe is falling very quickly. The same applies to a rapid stop initiated by the engineer in the engine 1 while the train is running. In the latter case, however, the control means 7 of the train integrity monitoring device is provided with the further information that the rapid stop was initiated by a measure taken by the engineer so that no undesired train separation is assumed. If the air pressure of the brake pipe is slowly falling during a troublcfrcc operation, i.e. during a troublcfrcc ride of the train, the presence of a minor leakage of the brake system of the train is inferred therefrom, and the compressor 4 arranged in the engine 1 is appropriately controlled to further supply the brake pipe with compressed air for reaching the air pressure necessary for a running operation. The air pressure is regulated to adopt the level required for the running operation. The predetermined values of the operating parameters are determined before by experiment or calculation taking corresponding operating conditions of the train (troublefree or disturbed operation) into account and are preferably stored in advance in the form of a data base or a map in the engine 1 in an appropriate memory, or there is a possibility of transmitting a complete and updated set of data from a stationary central control terminal to the control means 7 in the engine 1 . The values of the operating parameters stored in advance can furthermore be updated and/or corrected and supplemented by the engineer's respective input. Thus a complete data base is available to the train integrity monitoring device as regards the operating parameters of the train and especially concerning the characteristic curves of applying and releasing the car brakes (times necessary for applying the brake system). When comparing the predetermined values of the operating parameters, the currently provided operating conditions of the train are included in the determination of the train integrity. In detail, this may relate, for instance, to the values of the running speed, the routing of the line to be used and the train weight. It is necessary to take the running speed of the train into consideration, because the braking characteristics (speed of reaction of the brakes and the extent of brake force) are influenced at least partially at the individual wheel brakes of the cars in response to the speed. With respect to the routing the use of quite long gradient lines is relevant, while the train weight, i.e. the weight of each individual car, influences the braking characteristics of the entire train. The above-mentioned influencing factors can be taken into account in the predetermined values of the operating parameters in response to request so that the predetermined values of the operating parameters can be appropriately selected, adjusted or corrected for the given comparing operation and are used in connection with the engineer's instructions for applying or releasing the brake to determine the air flow volume and the air volume to be expected which has always to be supplied to the brake pipe. Thus the train integrity is substantially determined on the basis of the air volume used during operation of the train for various braking operations. Flowever, before the start of the train ride it is necessary to calibrate the train integrity monitoring device so that the device is provided with current data concerning the operating condition of the train. This is obtained by a so-called brake test which has to be performed after each train arrangement and after each car change (larger or smaller number of cars) before each departure. Upon the engineer's instruction the brake pipe 5 of the entire train is filled up by means of the compressor 4 disposed in the engine 1 , and it is optically established by the train crew if all brakes of the train are connected, all cars of the train are properly linked to the brake pipe and all individual wheel brakes of the cars are released. The brake test serves especially for determining if the compressed air passes freely to the end of the train, if all brakes can thus be operated by the engineer and if the brakes of the individual cars are properly working. During the brake test with a completely filled brake pipe 5 the control means 7 disposed in the engine 1 detects the air volume required for the entire train to release the brake and the air loss rate due to inevitable minor leakages. The brake test further includes activating the brakes, i.e. applying the brakes by appropriately reducing the air pressure in the brake pipe 5. In the same way as when releasing the brakes, the train crew optically checks if all brakes are properly applied. By this measure the control means 7 detects the speed of the pressure drop in the brake pipe 5 when a rapid stop is initiated. After the above-described brake test, which the railroad companies perform independently of further inspections of the brake system for safety reasons, the train integrity monitoring device is provided with the respective updates so that the train integrity can be reliably determined in accordance with the changes of the air pressure detected in the brake pipe and the compressed air supplied and discharged. The real operating parameters detected during a stop of the train, especially of the brake system, serve as a basis of the train integrity determination when the train is running and form the processing basis for data processing operations as performed by the control means 7 disposed in the engine 1. During the ride the current values can be detected continuously or else at short time intervals, the respective time intervals being determined in response to the operating condition of the train, especially in response to the running speed. According to the above description, the train integrity monitoring device is preferably arranged in the first car of the train, i.e. in the engine 1. The present inventive embodiment is not restricted hereto, however, as the components of the train integrity monitoring device may also be arranged in a car which is disposed directly behind the engine, if such car is equipped with an appropriate electric power supply and is linked with the engine for data transmission advantageously through an electric line. Such an arrangement of the train integrity monitoring device in a car of the train, preferably in the engine 1 , can also be used, if the type of train is a reversible train in which the engine is not arranged at the beginning of the train but at any location in the train or at the end of the train. Although a separation is improbable for the train part pushed by the engine, reversible trains serve for changing the running direction without removing the engine in a terminal station so that in the case of a reversible train also very often the situation occurs that the engine is arranged at the front end of the train. The train integrity monitoring device may also be incorporated in a vehicle control system and transmit, upon request or at predetermined time intervals, results of detection regarding the train integrity to a central control terminal for the route determination, for instance by means of a radio transmission line. The train integrity monitoring device according to the foregoing description offers the advantage for the operating sequence that the train integrity can be detected in a simple manner and with low expenditure on technical equipment, wherein the train can be dispatched relatively quickly especially after a marshalling of freight cars on a marshalling yard. The train integrity monitoring device entails operational advantages in connection with freight trains in which the individual cars are constantly newly marshalled. The execution of the brake test for calibrating the train integrity monitoring device and for detecting the basic operating parameters of the respective train constitutes no operational drawback, because the brake test has to be performed before departure in each case in the described manner for each train independently of its marshalling irrespective of a train integrity monitoring or any further measures. In the case of the above-described train integrity monitoring device, no expensive monitoring means have to be provided for arrangement at the end of the train and the possible troubles connected therewith when the train passes a tunnel are avoided. Furthermore also a defective brake can be detected and the train integrity monitoring device is adapted, in the event of subsequent changes of the brake system in a predetermined train marshalling, for instance if, due to a faulty action, a part of the cars is no longer connected to the brake pipe and thus cannot be braked any more, to identify this fault, because all basic data (initial values of the operating parameters) for the particular train marshalling were collected during the indispensable brake test before departure of the train and the original number of cars of the train was entered into the control means 7. Moreover it is possible to transmit updates concerning the speed of the train at which it has to run and the line to be used, especially in the event of a route deviation due to operational or technical problems to another line originally not planned, automatically or upon respective request from the central control terminal to the control means disposed in the engine so that thus the data stored in the control means can be changed, corrected and/or supplemented. While the invention has been described in terms of various specific embodiments, those skilled in the art will recognize that the invention can be practiced with modification within the spirit and scope of the claims.

Claims: MAT IS CLAIMED IS: 1. A train integrity monitoring device comprising: at least one sensor means (6) for detecting operating parameters of cars (2, 3) of the train; and a control means (7) connected to said sensor means (6) and disposed at one end of the train to control monitoring of train integrity, wherein the operating parameters detected by said sensor means (6) are compared to predetermined values of the operating parameters, and the integrity of the train is inferred in response to a result of comparison. 2. A device according to claim 1 , wherein said sensor means (6) detects operating parameters of a brake pipe (5) passing through the entire train. 3. A device according to Claim 2 wherein the operating parameters comprise at least an air pressure of said brake pipe (5) at a respective end of the train, an amount of air flowing into said brake pipe for releasing a brake system, an air loss rate, a respective times of lowering or increasing air pressure of said brake pipe (5) and all measures taken by an engineer. 4. A device according to any of Claims 1 to 3 wherein the values of the respective operating parameters are established by experiment or calculation and are stored for an access by said control means (7). 5. A device according to Claim 4 wherein said control means (7) compares the operating parameters detected by said sensor means (6) to previously stored values of the parameters to determine information about the train integrity. 6. A device according to Claim 4 wherein the operating parameters detected and the train integrity information of a central control terminal are transmitted automatically or upon request. 7. A device according to Claim 4 wherein a running speed of the train and information concerning the line to be used are taken into account in the stored data. 8. A device according to Claim 7 wherein a central control terminal transmits current information regarding the line to be used automatically or upon request to said control means (7). 9. A device according to Claim 1 wherein said sensor means detects the operating parameters a single location of the train. 10. A device according to Claim 9 wherein said sensor means (6) for detecting the operating parameters is disposed in said engine (1 ) or in a car (2) running directly behind said engine (1) and being connected to said engine (1 ). 1 1. A device according to Claim 9 wherein the operating parameters are detected continuously or at predetermined time intervals automatically or upon the engineer's instruction. 12. A device according to Claim 1 1 wherein the predetermined time intervals for detecting the operating parameters are adjusted by said sensor means (6) in response to one of a running speed, a type of train, and an engineer. 13. A device according to Claim 1 wherein the operating parameters detected by said sensor means (6) are compared to values of the respective operating parameters for corresponding operating conditions of the train. 14. A device according to Claim 9 wherein initial values of the operating parameters are detected by said sensor means (6) for calibrating said train integrity monitoring device when executing a brake test for the entire train. 15. A device according to Claim 13 wherein the determination of the train integrity is effected in response to amounts of air flowing into and out of said brake pipe (5) when the train is operated. 16. A device according to Claim 7 wherein data concerning the operating characteristics of the brake system when applying and releasing the brakes are taken into account in values of the operating parameters stored before. 17. A device according to Claim 14 wherein, in connection with the brake test, the engineer enters data concerning the current train into said control means (7) or such data are transmitted from the central control terminal to said control means (7).

Inventors: EVERITT WILLIAM H, EVERITT, WILLIAM, H.
Applicants: EVERITT WILLIAM H, GE HARRIS RAILWAY ELECTRONICS, EVERITT, WILLIAM, H., GE-HARRIS RAILWAY ELECTRONICS GMBH
Application year: 2000
Main classification: B61L15
IPC codes: B61L15