Method and Device for Monitoring Coupling Elements of a Vehicle

Abstract

A method and device for monitoring coupling elements of a vehicle, according to which at least one representative direction of relative movement is determined for a coupling element to be monitored, relative movements in the representative direction of movement of the coupling element to be monitored are measured and stored, and the stored relative movements are then evaluated such that the coupling elements can thus be monitored and their suitability for use in a vehicle can be determined.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to a method and a device for monitoring coupling elements of a vehicle.

2. Description of the Related Art

Coupling elements of a vehicle, such as spring elements or connecting elements, are subject to wear or ageing. Neither the wear nor the ageing of the coupling elements during operation of the vehicle can be prevented with the current prior art. These coupling elements must therefore be replaced at regular intervals or after a certain number of vehicle kilometers within the scope of a revision. The wear or ageing of such coupling elements has an influence on their material properties. Three main causes of the change in these material properties are the advance of time, the active environmental influences and the mechanical stress. These three main causes result in an overall damage to the coupling elements, which differs for each coupling element.

Coupling elements of a vehicle are subject to a large spectrum of mechanical stresses. These mechanical stresses are dependent on the respective mode of operation and on the condition of the roads traveled by the vehicle. In addition, the three main causes of the change in the material properties exhibit non-linear damage behavior, so that a prognosis of the overall damage to be expected is not possible.

In accordance with the prior art, the point in time of the revision is therefore not defined based on the actual overall damage of the coupling elements but, instead, based on a certain number of vehicle kilometers, after a specific time span has elapsed since a preceding revision, or a combination thereof.

Accordingly, there is the possibility within the scope of a revision of replacing coupling elements of the vehicle, which were still useable within the vehicle.

It is also possible that coupling elements of a vehicle are in use which, on account of their overall damage, no longer satisfy the requirements.

SUMMARY OF THE INVENTION

In view of the foregoing, it is an object of the invention to provide a method and a device for monitoring coupling elements of a vehicle in order to define their suitability of use.

This and other objects and advantages are achieved in accordance with the invention by a method, in which a significant relative movement direction is determined for a coupling element to be monitored, relative movements along the significant relative movement direction of the coupling element to be monitored are measured and stored and an evaluation of the stored relative movements takes place.

Coupling elements can be formed in a wide variety of designs. The significant relative movement directions are determined as a function of the design of the coupling elements and the forces acting operationally on the coupling element. For the coupling element to be monitored, only a relative movement direction can be determined as significant, nevertheless a number of significant relative movement directions per coupling element can however also be determined.

The relative movements along the at least one significant relative movement direction of the coupling element to be monitored are measured and stored. The stored relative movements are then evaluated.

The coupling elements execute relative movements on account of mechanical stress, where the relative movements result in damage to the coupling elements.

The advantage of the method in accordance with the invention is produced in that by measuring and evaluating these relative movements, it is possible to determine whether the coupling elements still satisfy the requirements or the extent of the damage to the coupling elements. The suitability of use of the coupling elements in the vehicle can thus also be determined at any time aside from a revision. In addition, a replacement of damaged coupling elements can, if necessary, be quickly triggered within the scope of a revision.

A further advantage of the method in accordance with the invention is that within the scope of a revision, only those coupling elements of the vehicle, on which damage was actually also determined by the inventive method, are replaced.

In a preferred embodiment of the method in accordance with the invention, the relative movements of the coupling element to be monitored are measured and stored via in each case a sensor and a slave arranged along the significant relative movement direction.

The distance between the sensor and the slave along the significant relative movement direction can be varied. All relative movements in the significant relative movement direction can thus be measured and stored.

In a further preferred embodiment of the method in accordance with this invention, the number of relative movements of the coupling element to be monitored, which lie above a previously defined threshold value, is stored.

Each relative movement of the coupling element that lies above the threshold value is counted equivalently as a standard unit. Relative movements of the coupling element that lie below the threshold value are not counted. This type of counting provides information relating to the number of relative movements which are greater than the threshold value.

The sensitivity of the disclosed embodiments of method can thus be set and relative movements of the coupling element that do not significantly contribute to damage of the coupling element can be filtered out.

In a preferred embodiment of the method in accordance with the invention, the evaluation of the stored relative movements of the coupling element to be monitored is achieved by comparing the number with at least one previously defined limit value. If the number of stored relative movements exceeds at least one of the previously defined limit values, this indicates that the coupling element no longer corresponds to the requirements on account of its damage.

The stored relative movements are transmitted without contact to a receive unit. The stored relative movements can thus also be transmitted to the receive unit during operation of the vehicle or during its travel.

The evaluation of the stored relative movements of the coupling element to be monitored preferably takes place after in each case time intervals of essentially the same length or after essentially the same number of vehicle kilometers.

It is assumed that the forces in the means acting on the coupling element are the same size within this time interval of the same length or after in each case the same number of vehicle kilometers.

By comparing the relative movements stored at the respective points in time or after the respective number of kilometers with relative movements stored prior to these respective time points or prior to this respective number of kilometers, damage to the coupling element can be determined.

The threshold value and/or the limit value is preferably defined based on measurement travel data or based on simulations of the vehicle.

The threshold value and/or the limit value, or the limit values, which correspond to different damage levels of the coupling element to be examined, can be produced based on the analysis of measurement travel data in combination with damage models.

It is also possible to simulate measurement travel data of the vehicle virtually in order thus to generate the limit values virtually.

During the test run of the vehicle, the relative movements of the coupling element to be monitored are evaluated and the threshold value is defined such that only those relative movements of the coupling element that significantly contribute to damage of the coupling element are stored. The limit values that correspond to the different damage levels are defined such that if the number of relative movements of the coupling element exceeds these limit values, the status of the component is graduated with respect to its suitability of use. Therefore each coupling element exhibits a service life or suitability of use status, as a result of which precise planning of the revision interval and thus an optimum component usage can occur.

A last limit value is defined such that if the number of relative movements of the coupling element exceeds this limit value, then the coupling element no longer satisfies the requirements during use in motor vehicles on account of damage.

The coupling elements to be monitored are preferably formed as spring elements, connecting elements or combinations thereof. For instance, the term coupling element is to be understood as combinations of two spring elements, two connecting elements, a spring element and a connecting element or also any combination comprising a number of spring elements, connecting elements or both.

The vehicle is preferably formed as a rail vehicle. Unnecessary revisions of the rail vehicles can be prevented via the method in accordance with the disclosed embodiments.

In particular, this is therefore advantageous because revisions of rail vehicles can only be performed with a relatively high technical outlay. Moreover the corresponding rail vehicle is not available for normal operation during the revision period.

The revision time is preferably defined as a result of the evaluation of the stored relative movements of the coupling elements to be monitored.

A date for a revision can therefore be defined in an accurately timed manner.

An analysis of the mode of operation, in particular with respect to operation-oriented stresses on the coupling elements, occurs by evaluating the stored relative movements of the coupling elements to be monitored.

The accuracy of the disclosed embodiments of the method can be continuously improved by incorporating the results of this analysis when defining the limit value or the threshold value. A learning process can thus be generated. In addition, the results can also influence new developments of coupling elements.

It is a further object of the invention to provide a system for monitoring a coupling element integrated in a vehicle including a coupling element arranged between components of the vehicle, a sensor and a slave, the distance of which can be varied along a significant movement direction of the coupling element, wherein the sensor and/or the slave is fixed to the component or the coupling element, also included is a transmit unit for transmitting data stored in the slave, and a receive unit arranged outside of the vehicle for receiving the data transmitted by the transmit unit.

If the coupling element executes relative movements in the at least one significant relative movement direction, sensors and/or slaves therefore execute these relative movements with one another.

The relative movements of the coupling element to be monitored along the at least one significant relative movement direction are measured, stored and transmitted to the transmit unit, via the system in accordance with the invention.

All relative movements in the significant relative movement direction can thus be measured and stored.

The following arrangements of sensor and slave are possible:

• • The sensor and slave are fixed to the coupling element
  • The sensor is fixed to the coupling element and the slave is fixed to the component
  • The sensor is fixed to the component and the slave is fixed to the coupling element
  • The sensor and slave are fixed to the component

The data stored in the slave can thus be transmitted without contact to the receive unit arranged outside of the vehicle. The receive unit is installed fixedly such that the stored data in the slave can be transmitted without contact to the receive unit in the case of a vehicle travelling past the receive unit.

Other objects and features of the present invention will become apparent from the following detailed description considered in conjunction with the accompanying drawings. It is to be understood, however, that the drawings are designed solely for purposes of illustration and not as a definition of the limits of the invention, for which reference should be made to the appended claims. It should be further understood that the drawings are not necessarily drawn to scale and that, unless otherwise indicated, they are merely intended to conceptually illustrate the structures and procedures described herein.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 a is a schematic illustration of an exemplary coupling element 1 formed as a coil spring;

FIG. 2 is a schematic illustration of an exemplary coupling element 1 formed as a conical spring;

FIG. 3 is a schematic illustration of an exemplary contactless transmission of data to a receive unit 6 during the travel of a vehicle 7; and

FIG. 4 is a flowchart of the method in accordance with the invention.

DESCRIPTION OF THE EXEMPLARY EMBODIMENTS

FIG. 1 is a schematic illustration of an exaplary coupling element 1 formed as a coil spring. For the coupling element 1 to be monitored, a significant relative movement direction 2 is determined. A sensor 3 and a slave 4 are fixed to the component 9. The distance between the sensor 3 and slave 4 can be varied in the significant relative movement direction 2. For instance, this distance is enlarged by tensile forces exerted on the coil spring in the significant relative movement direction 2 or reduced by pressure forces exerted on the coil spring in the significant relative movement direction 2. If the coupling element 1 executes relative movements in the direction of the significant relative movement direction 2, the sensor 3 and/or the slave 4 therefore also execute these relative movements. Its distance along the significant relative movement direction 2 at least changes. Relative movements of the coupling element 1 to be monitored along the significant relative movement direction 2 can thus be measured and stored. Only such relative movements that lie above a previously defined threshold value are stored as data. This data is stored in each case equally as a standard unit in the slave 4. In the memory of the slave 4, the number of any relative movements that lie above the threshold value is finally stored. For instance, the smallest relative movements, which have no or almost no contribution with respect to damage of the coupling element 1, can thus be excluded.

The data stored in the slave 4 is transmitted to a receive unit 6 by a transmit unit 5. The transmitted data is then evaluated.

The evaluation of the data takes place such that a comparison of the number of relative movements lying above the threshold value with at least one previously defined limit value occurs.

This evaluation of the data occurs after in each case time intervals of essentially the same length or after in each case essentially the same number of kilometers of the coupling element 1, such as in a vehicle 7 shown in FIG. 3. It is assumed that the forces in the means acting on the coupling element 1 are the same size within this time interval of the same length or after in each case the same number of vehicle kilometers 7. If the comparison shows that the number of relative movements of the coupling element 1 lying above the threshold value exceeds the limit value, then a revision time instance is defined for the vehicle 7.

An analysis of the mode of operation of the vehicle 7 shown in FIG. 3, in particular with respect to operation-oriented stresses of the coupling element 1, also occurs by evaluating the stored relative movements of the coupling element 1 to be monitored.

The accuracy of the method in accordance with the invention can be continuously improved by incorporating the results of this analysis when defining the limit value or the threshold value. A learning process can thus be generated. In addition, the results can also influence new developments of coupling elements 1.

FIG. 2 is a schematic illustration of an exemplary coupling element 1 formed as a conical spring. The sensor 3 is arranged on the coupling element 1. The slave 4 is arranged with the transmit unit 5 on the component 9. The distance between the sensor 3 and slave 4 can be varied along the significant relative movement direction 2. The relative movements of the coupling element 1 are stored in the slave 4, as already explained with the aid of FIG. 1, where relative movements are transmitted from the transmit unit 5 to the receive unit 6.

FIG. 3 is a schematic illustration of an exemplary use of the method in accordance with the invention in a vehicle 7 formed as a rail vehicle with a contactless transmission of the data via the transmit units 5 to the receive unit 6 during the travel of the rail vehicle in the travel direction 8.

Coupling elements 1 can be monitored as a result and their suitability of use in a vehicle 7 can be determined.

FIG. 4 is a flowchart of the method for monitoring coupling elements (1) of a vehicle (7). The method comprises determining a significant relative movement direction (2) for a coupling element (1) to be monitored, as indicated in step 410. Next, relative movements along the significant relative movement direction (2) of the coupling element (1) to be monitored are measured and stored, as indicated in step 420. The stored relative movements that occur are now evaluated, as indicated in step 430.

Thus, while there have been shown, described and pointed out fundamental novel features of the invention as applied to a preferred embodiment thereof, it will be understood that various omissions and substitutions and changes in the form and details of the devices illustrated, and in their operation, may be made by those skilled in the art without departing from the spirit of the invention. For example, it is expressly intended that all combinations of those elements which perform substantially the same function in substantially the same way to achieve the same results are within the scope of the invention. Moreover, it should be recognized that structures and/or elements shown and/or described in connection with any disclosed form or embodiment of the invention may be incorporated in any other disclosed or described or suggested form or embodiment as a general matter of design choice. It is the intention, therefore, to be limited only as indicated by the scope of the claims appended hereto.

Claims

1.-12. (canceled)

13. A method for monitoring coupling elements of a vehicle, comprising: determining a significant relative movement direction for a coupling element to be monitored;measuring and storing relative movements along the significant relative movement direction of the coupling element to be monitored; andevaluating the stored relative movements.

14. The method as claimed in claim 13, wherein relative movements of the coupling element to be monitored are each measured and stored via a sensor and a slave arranged along the significant relative movement direction.

15. The method as claimed in claim 13, wherein a number of relative movements of the coupling element to be monitored which lie above a previously defined threshold value is stored.

16. The method as claimed in claim 14, wherein a number of relative movements of the coupling element to be monitored which lie above a previously defined threshold value is stored.

17. The method as claimed in claim 15, wherein the evaluation of the stored relative movements of the coupling element to be monitored occurs by comparing the number with at least one previously defined limit value.

18. The method as claimed in claim 13, wherein stored relative movements are transmitted without contact to a receive unit.

19. The method as claimed in claim 13, wherein evaluations of stored relative movements of the coupling element to be monitored occurs after one of (i) each time interval of essentially the same length or (ii) after essentially each same number of vehicle kilometers.

20. The method as claimed in claim 15, wherein at least one of (i) the previously defined threshold value and (ii) a limit value is defined based on one of (i) measurement travel data and (ii) simulations of the vehicle.

21. The method as claimed in claim 13, wherein the coupling elements to be monitored are formed as spring elements, connecting elements or combinations thereof.

22. The method as claimed in claim 13, wherein the vehicle is a rail vehicle.

23. The method as claimed in claim 13, wherein a revision time point for the vehicle is defined as a result of the evaluation of the stored relative movements of the coupling elements to be monitored.

24. The method as claimed in claim 13, wherein said evaluating the stored relative movements comprises analyzing a mode of operation of the vehicle.

25. The method as claimed in claim 24, wherein the analysis of the mode of operation of the vehicle is performed with respect to operation-oriented stresses of the coupling elements.

26. A system for monitoring at least one coupling element incorporated in a vehicle, comprising: a coupling element arranged between a plurality of components of the vehicle;a sensor;a slave spaced apart from the sensor, a distance between the sensor and slave varying along a significant movement direction of the coupling element, and at least one of the sensor and the slave be affixed to a respective component of the plurality of components or the coupling element;a transmitter for transmitting data stored in the slave; anda receiver arranged outside of the vehicle which receives data transmitted by the transmitter.