SE540632C2 - System for monitoring axle loads in motor vehicles - Google Patents

Abstract

Method, device and system for operating a motor vehicleA method for operating a motor vehicle, comprises the steps of providing motor vehicle data (KF_D) which encompass at least items of information regarding the motor vehicle (1) and/or a trailer (5), and receiving an identifier (K_GS) of at least one weight sensor (3). Furthermore, the method comprises the step of comparing the received identifier (K_GS) with a predefined identifier (K_ZE) for the at least one weight sensor (3). Furthermore, the method comprises the step of receiving measurements signals (MS_G) of the at least one weight sensor (3) which are representative of an axle load of an axle (7) of the motor vehicle (1) or of the trailer (5). Furthermore, the method comprises the step of determining a weight force (F_G) in a manner dependent on the received measurement signals (MS_G) and the provided vehicle data (KF_D) if correlation of the received identifier (K_GS) with the predefined identifier (K_ZE) of the at least one weight sensor (3) has been determined.

Description

Description System for monitoring of axle loads in motor vehicles The present invention relates to a method, to a device corresponding to the method, and to a system for operating a motor vehicle, each of which are suitable for permitting reliable monitoring of axle loads of the motor vehicle and/or changing motor vehicle-trailer combinations.

Axle loads of motor vehicles or trailers are determined and monitored for example by way of pressure sensors or ride-height sensors. In this case, pressure sensors are arranged for example on air spring-mounted axles of the motor vehicle or of the trailer, and ride-height sensors are arranged on leaf springmounted axles of the motor vehicle or of the trailer. From measurement signals of said sensors, together with items of information regarding the geometry and material of components involved, it is possible to determine weight forces acting on the respective axles. The resulting axle loads are for example displayed to the driver of the motor vehicle in order that he or she can inspect a load of the motor vehicle and of the trailer.

Such systems for monitoring axle loads generally exhibit adequate accuracy only when the vehicle is at a standstill, for example because roadway unevennesses and braking processes during driving operation lead to load alterations and can thus greatly influence the detected weight values. Furthermore, such systems are generally set for fixedly assigned motor vehicle-trailer combinations, in the case of which no provision is made for alternating operation between different motor vehicles and trailers. Furthermore, such systems offer various avenues of attack for tampering with the detected measurement results and determined weight values.

Monitoring of stationary or rolling motor vehicles with or without a trailer by inspection authorities is performed for example in a stationary manner at rest areas by way of scales that are set up there or integrated into the roadway surface. In this case, monitoring of axle loads at rest areas is timeconsuming for both inspection officials and drivers, and impedes the free flow of traffic. By comparison, automatic measurements integrated into the roadway surface can possibly be carried out more quickly but are generally expensive and tied to a certain level of infrastructure.

It is an object to provide a method, a device corresponding to the method, and a system for operating a motor vehicle, each of which are suitable for permitting reliable and secure detection, transmission and/or monitoring of axle loads of the motor vehicle and/or of different motor vehicle-trailer combinations.

According to a first aspect of the invention, a method for operating a motor vehicle, comprises the steps of providing motor vehicle data which encompass at least items of information regarding the motor vehicle and/or a trailer, and receiving an identifier of at least one weight sensor. Furthermore, the method comprises the step of comparing the received identifier with a predefined identifier for the at least one weight sensor. Furthermore, the method comprises the step of receiving measurements signals of the at least one weight sensor which are representative of an axle load of an axle of the motor vehicle or of the trailer. Furthermore, the method comprises the step of determining a weight force in a manner dependent on the received measurement signals and the provided vehicle data if correlation of the received identifier with the predefined identifier of the at least one weight sensor has been determined.

By means of the described method, it is for example possible, even in the case of changing motor vehicle-trailer combinations, for the measurement signals of the at least one weight sensor to be reliably and securely detected and transmitted, and thus for the axle loads of the motor vehicle and/or of the trailer to be monitored. The predefined identifier for the at least one weight sensor is for example stored in a memory which is assigned to the at least one weight sensor. For example, the at least one weight sensor has a dedicated memory in which the predefined identifier is stored. In this case, the at least one weight sensor represents a sensor which permits a determination of a weight force in a manner dependent on its measurement signals. For example, the at least one weight sensor is a pressure sensor, a tire pressure sensor, a right-hand sensor or a profile depth sensor.

By means of the comparison of the received identifier and predefined identifier of the at least one weight sensor, tamperproof detection of measurement signals and monitoring of the axle loads is possible, or tampering with the measurement signals and the determined axle loads is at least made more difficult in the context of the method. The identifier of the at least one weight sensor comprises for example items of information regarding a manufacture and a model designation of the weight sensor, and includes for example an electronic identification number which uniquely identifies the weight sensor. Furthermore, the weight sensor is advantageously also, as a component, externally labeled with a unique identification number. These items of information may for example be implemented during the production of the weight sensor or of the motor vehicle and are for example accessible only to authorized personnel working for example at the vehicle manufacturer or in certain installation workshops. Access to and editing of the identifier are then for example possible only with suitable programming means and are protected by way of an electronic security key which is realized for example as a password or an electronic chip card. The corresponding identifier is then for example also stored, as a predefined identifier, in a database which is accessible to a device which is designed for carrying out the described methods.

During a comparison of the received identifier with the predefined identifier of the weight sensor, it is for example the case that the above-described items of information are compared, and the method is allowed to proceed for example only in the event of complete positive correlation. It is then for example the case that the identifier of the at least one weight sensor is received, and compared with the predefined identifier, once or several times during every driving cycle of the motor vehicle, thus contributing to certified implementation of the method. Alternatively or in addition, the device corresponding to the method is set during the production and activation process by authorized personnel such that, for example, the weight sensor and the device can be designated as being certified and secure upon leaving the factory.

The at least one weight sensor is for example equipped with electronics for processing the measurement signals, which electronics furthermore permit for example wireless and/or wired communication with further components involved in the context of the method. For example, the at least one weight sensor has a communication interface which is designed to transmit the identifier and the received measurement signals to the corresponding device, in order thereby to make it possible for axle loads to be reliably determined in the context of the method.

The motor vehicle data that are made available comprise for example items of information regarding a geometry and/or a material of different components of the motor vehicle and/or of the trailer. For example, the at least one weight sensor is a pressure sensor which is assigned to a tire or to an air-spring bellows of the motor vehicle or of the trailer, and the motor vehicle data comprise items of information regarding a crosssectional area of the air-spring bellows, such that from this, a weight force can be determined. Alternatively, the at least one weight sensor is a ride-height sensor which is assigned to a leaf spring-mounted axle of the motor vehicle or of the trailer and which monitors a change in position of the leaf springs. In this case, the motor vehicle data comprise for example items of information regarding the material of the leaf springs, and make associated spring characteristic curves available.

The described methods can thus be realized by means of at least one certified weight sensor and a device corresponding to the method, which can also be referred to as certified control unit. Said components are then for example arranged in or on, and in each case uniquely assigned to, the motor vehicle and/or the trailer. Reliable and secure monitoring of axle loads of the motor vehicle and/or of the trailer is thus possible.

In one refinement of the first aspect, the method comprises the steps of receiving measurement signals of at least one speed sensor which are representative of a speed of the motor vehicle, and determining a speed of the motor vehicle in a manner dependent on the received measurement signals. Furthermore, the method comprises the step of determining the weight force in a manner dependent on the determined speed.

In this context, the method is enhanced such that the determined speed of the motor vehicle is also incorporated into the determination of the weight force acting on an axle of the motor vehicle or of the trailer.

In this way, it is for example possible for an axle load of the motor vehicle or of the trailer to be determined and monitored even during travel. For example, it is possible for roadway unevennesses encountered during travelling operation of the motor vehicle to also be taken into consideration in the determination of a weight force. In this context, by means of the weight sensors, roadway unevennesses are detected dynamically as load alterations during a driving cycle. In this case, it is for example the case that a load alteration occurs firstly at a front axle of the motor vehicle, and immediately thereafter, at a predeterminable point in time, a load alteration occurs at a subsequent axle, for example a drive axle or a trailer axle. From known installation conditions, such as axle spacings, and the determined speed, it is thus possible in the context of the method to monitor, and check within certain limits, a time of a load alteration and a change in the determined weight force, which can inter alia improve and/or confirm the reliability and security of the method and of the corresponding device. Furthermore, with the incorporation of the determined speed, a load alteration owing to a braking or acceleration process can also be taken into consideration.

Furthermore, by way of the determination of the speed of the motor vehicle, it is also possible to determine when the motor vehicle comes to stop. For example, if a speed of the motor vehicle of zero meters per second is determined, a measurement of the axle loads is for example particularly accurate because it is not influenced by roadway unevennesses and braking or acceleration processes.

In a further refinement of the first aspect, the method comprises the step of recording the determined weight force by way of a recording unit.

In this way, it is possible for the determined weight forces to be stored and logged in the recording unit during operation of the motor vehicle. In this way, long-term monitoring and evaluation of the axle loads of the motor vehicle and/or of the trailer is for example possible. For example, it is thus the case that, during a driving cycle, loading and/or unloading of the motor vehicle and/or of the trailer is logged and can even retrospectively be compared with any specifications and, if necessary, inspected by inspection officials.

The recording unit is realized for example by way of a certified digital tachograph which logs the determined weight forces and axle loads in the context of the method and for example also displays error messages which notify the driver or inspection official of discrepancies in the determination of the axle loads and/or comparison of the identifiers of the one or more weight sensors. In this way, it is thus possible to replicate a driving cycle of the motor vehicle and/or of the trailer with regard to the axle loads, whereby, for example, tampering with the detected measurement signals or with the determined weight forces is made considerably more difficult. Furthermore, by means of the recording unit, it is possible in the context of the method for exceedances of admissible axle loads to be registered. With knowledge of this function for example on the part of the driver, it may be the case that loading of motor vehicles and/or trailers will be precisely monitored and overloading will be avoided, thereby contributing to greater safety in the road traffic environment.

According to a second aspect of the invention, a device is designed to carry out a method of the above-described refinements of the first aspect.

With this aspect of the invention, a device corresponding to the method described above is claimed, which device permits reliable, secure and certified monitoring of axle loads of the motor vehicle and/or of the trailer. In this context, the method is realized for example by way of certified weight sensors and a certified control unit, which is coupled in terms of signal transmission to the certified weight sensors and to a certified recording unit.

According to a third aspect of the invention, a system comprises a device according to the above-described second aspect, which device is arranged in or on the motor vehicle or the trailer. Furthermore, the system comprises at least one certified weight sensor which is coupled in terms of signal transmission to the device and which is arranged in or at a predefined location on the motor vehicle or on the trailer and which is assigned to an axle of the motor vehicle or of the trailer.

In this way, a system is realized which makes it possible to carry out a method as described above and which is thereby conducive to tamper-proof detection, transmission and monitoring of axle loads of the motor vehicle and/or of the trailer. For example, the certified weight sensor is a tire pressure sensor which is arranged in an air-spring bellows or a tire of the motor vehicle and which monitors an axle load of the motor vehicle. In this context, the certified pressure sensor is for example installed and programmed by authorized personnel already during the production of the vehicle or axle, and thus exhibits the certification described in the context of this invention. This is for example indicated by way of a label on the at least one weight sensor. Such a label then includes for example items of information such as the chassis number and name of the authorized installation site, and, as a seal on the weight sensor, said label cannot be removed non-destructively.

The device and the at least one certified weight sensor are then for example provided, at the time of installation, with a unique identification which comprises for example an identification number and an electronic signature. In this case, the device and the certified weight sensor are coupled to one another and, for example, items of information regarding axle configuration and axle sequence of the motor vehicle and/or of the trailer are stored for example in a data memory of the device. Alternatively or in addition, said items of information and further items of information, such as the motor vehicle data, are made available externally to the motor vehicle and the trailer in a back-end, and can be retrieved in the context of the method.

In one refinement of the third aspect, the at least one certified weight sensor is a pressure sensor, in particular a profile depth sensor, which is arranged in a tire of the motor vehicle or of the trailer.

The pressure sensor is for example arranged in a tire of the motor vehicle or of the trailer, and in this case monitors the pressure of the respective tire and can accordingly also be referred to as tire pressure sensor. For example, the system also comprises multiple tire pressure sensors which, as certified weight sensors, permit a determination of a weight force and of an axle load of the respective tire and of the respective axle.

In this context, the tire pressure sensor is for example arranged internally on an inner side of the tire and monitors rolling behavior of the tire. The rolling behavior in this case provides information regarding a load acting on the axle to which the tire is assigned, and thus permits, for example in the context of an evaluation by way of software, a determination of the weight force and a determination of the axle load. Furthermore, by means of the tire pressure sensor, the monitored rolling behavior can also be evaluated for the purposes of determining and monitoring a profile depth of the tire. Consequently, the tire pressure sensor can also be referred to as profile depth sensor. What is also possible is a combination of different certified weight sensors which are arranged in or at a predefined location on the motor vehicle or on the trailer.

In one refinement of the third aspect, the system comprises a recording unit which is coupled in terms of signal transmission to the device.

The recording unit permits, as described above, digital logging of the determined weight forces acting on the respective axles of the motor vehicle and/or of the trailer. In this case, the device, the at least one weight sensor and the recording unit are in each case designed to communicate with one another and transmit or receive the detected measurement signals and predetermined weight forces and axle loads. Communication for the transmission and receiving of data is realized for example by way of wireless communication, or is realized for example by way of wired Controller Area Network (CAN) connections between the motor vehicle and the trailer and the above-described components. Another possible means of communication is for example a powerline connection, in the case of which existing electrical cabling is generally utilized for data transmission.

The communication between the described components is performed for example in each case with an associated signature in order to ensure the validity of the transmitted and received data, and make tampering more difficult.

In a further refinement of the third aspect, the device and/or the at least one certified weight sensor are/is coupled cohesively and/or in positively locking fashion and/or in nonpositively locking fashion to the motor vehicle or to the trailer.

In this way, a system is realized in which the components required for carrying out the above-described method are arranged, to a certain degree, in tamper-proof fashion in or on the motor vehicle or the trailer. For example, the device, as a certified control unit, is cohesively connected to a vehicle frame of the motor vehicle or of the trailer, for example by way of welding. In this context, it is consequently no longer possible for the certified control unit to be non-destructively detached from the motor vehicle or the trailer. Furthermore, the device and/or the at least one certified weight sensor is for example provided with an anti-tamper seal which is applied by authorized personnel during the installation of said components. Thus, unauthorized dismounting or repositioning of the device and of the certified weight sensor is visible from the outside, whereby a quick external inspection of the system is also possible. Such anti-tamper seals are then, for example similarly to the abovementioned labels and the electronic security key, accessible only to authorized persons working for example at authorized vehicle manufacturers, body manufacturers and installation workshops.

In a further refinement of the third aspect, the at least one certified weight sensor is arranged in an air-spring bellows of the motor vehicle or of the trailer.

In this way, a mechanically tamper-proof arrangement of the at least one certified weight sensor is for example realized, in the case of which the weight sensor is for example internally vulcanized into the air-spring bellows. Tampering with the certified weight sensor and the position thereof is thus made considerably more difficult and is possible only with prior destruction of the air-spring bellows. In this way, external intervention is for example prevented, contributing to reliable and secure detection and monitoring of axle loads of the motor vehicle or of the trailer.

In a further refinement of the first aspect, the system comprises at least one weight sensor which is assigned to the motor vehicle or to the trailer and which is coupled in terms of signal transmission to the recording unit.

In this context, the system is enhanced to include a speed sensor by means of which a determination of the axle loads in a manner dependent on the speed of the motor vehicle is possible. In this way, it is possible for speed-induced changes in the axle loads, such as roadway unevennesses, braking or acceleration processes to also be taken into consideration in the determination of the weight forces acting on the respective axles.

In a further refinement of the third aspect, the motor vehicle has a management unit and the trailer has the device, which management unit and device are each designed to communicate with one another in terms of signal transmission when the motor vehicle and the trailer are in a coupled state.

The management unit, as a higher-level entity, is designed for example to coordinate the data transfer between the at least one certified weight sensor, the device and the recording unit. Furthermore, by means of the management unit, it is also possible for different motor vehicle-trailer combinations to be configured with regard to the implementation of one of the above described methods, and for it to be checked whether the components involved exhibit corresponding certification.

For example, the one or more trailers with the device are designated as being certified upon leaving the factory, and are coupled to the motor vehicle for operation. In this case, such coupling also includes a coupling in terms of signal transmission, which may be realized in wireless or wired form. For example, communication is realized by way of a motor vehicletrailer CAN connection, thus permitting data transfer between the motor vehicle and trailer and monitoring and management of the determined axle loads.

Exemplary embodiments of the invention will be discussed in more detail below on the basis of the schematic drawings, in which: figure 1 shows a flow diagram of a program executed in a device, figure 2 shows a system for operating a motor vehicle.

Figure 1 illustrates a flow diagram of a program for operating a motor vehicle 1, which program is executed for example in a device 10 of the motor vehicle 1 or over trailer 5. The device 10 is for example realized in the form of a certified control unit, and comprises for example a data and program memory and a processing unit. The device 10 is coupled in terms of signal transmission to at least one weight sensor 3 which is assigned to an axle of the motor vehicle 1 or of the trailer 5.

In a first step SI, the program started. The start of the program may for example occur close to a time of starting of an engine 16 of the motor vehicle 1.

In a step S3, the device 10 receives an identifier K_GS of the at least one weight sensor 3, which identifier comprises for example items of information regarding a manufacture and a model designation of the weight sensor 3. The identifier K_GS includes for example an electronic identification number which uniquely identifies the weight sensor 3. Furthermore, the weight sensor 3 is advantageously also, as a component, externally labeled with a unique identification number.

For example, the at least one weight sensor 3 has a dedicated memory in which the identifier K_GS is stored. The memory is designed such that the identifier K_GS is accessible only to authorized persons working for example at a vehicle manufacturer or in certain installation workshops. Access to and editing of the identifier K_GS are then for example possible only with suitable programming means and are protected by way of an electronic security key which is realized for example as a password or an electronic chip card. The corresponding identifier K_GS is then for example also stored, as a predefined identifier K_ZE, in a database which is accessible to a device 10 for executing the program.

In a step S5, the device 10 checks whether the received identifier K_GS correlates with the predefined identifier K_ZE. In this context, the device 10 compares the received identifier K_GS with the predefined identifier K_ZE, which is for example stored in a data memory of the device 10 or which may also be retrieved from a back-end arranged externally to the motor vehicle 1. If the comparison of the received identifier K_GS with the predefined identifier K_ZE does not yield a correlation, the program can for example return to the step S3. However, if the received identifier K_GS correlates with the predefined identifier K_ZE for the at least one weight sensor 3, the program proceeds to a step S7.

In the comparison of the received identifier K_GS with the predefined identifier K_ZE for the at least one weight sensor 3, it is for example the case that the above-described items of information, such as manufacturer, model designation and electronic identification number, are compared, and the method is allowed to proceed for example only in the event of complete positive correlation. It is then for example the case that the identifier K_GS of the at least one weight sensor 3 is received, and compared with the predefined identifier K_ZE, once or several times during every driving cycle of the motor vehicle 1, thus contributing to certified implementation of the method. Alternatively or in addition, the device 10 is set during the production and activation process by authorized personnel such that, for example, the weight sensor 3 and the device 10 can be designated as being certified and secure upon leaving the factory, and in the context of the program do not imperatively have to be checked with regard to a signature.

By means of the comparison of the received identifier K_GS and predefined identifier K_ZE of the at least one weight sensor 3, tamper-proof detection of measurement signals MS_G of the weight sensor 3 and monitoring of the axle loads is possible, or tampering with the measurement signals MS_G and with the axle loads that can be determined therefrom is at least made more difficult.

In the step S7, the acquisition of the measurement signals MS_G of the at least one weight sensor 3, from which measurement signals an axle load of an axle 7 of the motor vehicle 1 or of the trailer 5 is determined during the further process, is commenced.

Furthermore, in a step S8, measurement signals MS_V of a speed sensor 9 are acquired, from which measurement signals a speed GE of the motor vehicle 1 is determined during the further process.

In a step S9, in a manner dependent on the received measurement signals MS_G of the at least one weight sensor 3 and in a manner dependent on the received measurement signals MS_V of the speed sensor 9, a weight force F_G acting on an axle of the motor vehicle 1 or of the trailer 5 is determined. In this context, motor vehicle data KF_D are incorporated into the determination of the weight force F_G, which motor vehicle data are made available for example in a data memory of the device or in the back-end arranged externally to the motor vehicle 1.

The motor vehicle data KF_D that are made available comprise for example items of information regarding a geometry and/or a material of different components of the motor vehicle 1 and/or of the trailer 5. For example, the at least one weight sensor 3 is a pressure sensor which is assigned to a tire or to an airspring bellows of the motor vehicle 1 or of the trailer 5, and the motor vehicle data KF_D comprise items of information regarding a cross-sectional area of the air-spring bellows, such that from this, together with measurement signals MS_G of the weight sensor 3, a weight force F_G can be determined. Alternatively, the at least one weight sensor 3 is a ride-height sensor which is assigned to a leaf spring-mounted axle of the motor vehicle 1 or of the trailer 5 and which monitors a change in position of the leaf springs. In this case, the motor vehicle data KF_D comprise for example items of information regarding the material of the leaf springs, and make associated spring characteristic curves available.

The determined weight forces F_G correspond to an axle load of the respective axle 7 to which the at least one weight sensor 3 is assigned. In a step Sll, the determined axle loads can be recorded and stored in a recording unit 12 in order thereby to permit for example long-term monitoring of the axle loads of the motor vehicle 1 and/or of the trailer 5.

The determined weight forces F_G are then for example stored and logged in the recording unit 12 during the operation of the motor vehicle 1. For example, it is thus the case that, during a driving cycle, loading and/or unloading of the motor vehicle 1 and/or of the trailer 5 is logged and can even retrospectively be compared with any specifications and, if necessary, inspected by inspection officials. In this way, a moderate increase or decrease in axle loads, for example between a vehicle stoppage and travel of the motor vehicle 1 possibly with a trailer 5, is checked. In this regard, for example, application-specific load coefficients are stored which, for example, are indicative of a type of load such as bulk material, piece goods, heavy load, or container.

The recording unit 12 is for example realized by way of a certified digital tachograph which logs the determined weight forces F_G and axle loads in the context of the method and for example also displays error messages which notify the driver or inspection official of discrepancies in the determination of the axle loads and/or comparison of the received identifier K_GS with the predefined identifier K_ZE of the at least one certified weight sensor 3. In this way, it is thus possible to replicate a driving cycle of the motor vehicle 1 and/or of the trailer 5 with regard to the axle loads, whereby, for example, tampering with the detected measurement signals MS_G, MS_V or with the determined weight forces F_G is made considerably more difficult. Furthermore, by means of the recording unit 12, it is possible in the context of the method for exceedances of admissible axle loads to be registered. With knowledge of this function for example on the part of the driver of the motor vehicle 1, it may be the case that loading of motor vehicles 1 and/or trailers 5 will be precisely monitored and overloading will be avoided, thereby contributing to greater safety in the road traffic environment.

The program is for example carried out continuously after step Sll, such that, during the operation of the motor vehicle 1, the program proceeds again to step S7 or to step S3 depending on whether the identifier K_GS of the weight sensor 3 is to again be received and compared with the predefined identifier K_ZE.

In a step S13, the program for operating a motor vehicle 1 is ended. This occurs for example when the motor vehicle 1 or the engine 16 is shut down.

Figure 2 illustrates an exemplary embodiment of a system which comprises the motor vehicle 1 and a trailer 5.

The motor vehicle 1 is realized for example in the form of a passenger motor vehicle which is coupled to the trailer 5, or is realized in the form of a heavy goods motor vehicle which, as a tractor unit, tows one or more trailers 5. Figure 2 illustrates only one trailer 5, though it is also possible for multiple trailers 5 to be provided which are for example arranged one behind the other and are coupled to one another in each case.

In embodiments, on each axle 7 of the motor vehicle 1 and of the trailer 5, there is arranged in each case one weight sensor 3 which is for example in the form of a pressure sensor or a rideheight sensor. In further embodiments, the weight sensor 3 is arranged only at a single axle 7. In further embodiments, in each case one weight sensor 3 is arranged on some of the axles 7, and no weight sensor 3 is provided on the other axles 7. Furthermore, the motor vehicle 1 and the trailer 5 each have a device 10, said devices each being coupled in terms of signal transmission to two weight sensors 3 and one speed sensor 9. In this exemplary embodiment, two speed sensors 9 are illustrated, with one on or in the motor vehicle 1 and one on or in the trailer 5, though it is alternatively also possible for only one speed sensor 9 to be provided. Furthermore, it is likewise possible for more axles 7 to be provided than are illustrated.

In the exemplary embodiment in figure 2, the motor vehicle 1 and the single trailer 5 illustrated are connected to one another by way of a coupling 14. In this exemplary embodiment, the coupling 14 represents both a mechanical coupling of the motor vehicle 1 and of the trailer 5 and also a coupling in terms of signal transmission, for example by way of an electrical connection, such as for example CAN or powerline connections. The coupling in terms of signal transmission may alternatively or additionally be realized in wireless form, permitting communication and data transfer between motor vehicle 1, the trailer 5 and the components involved for monitoring the axle loads.

The devices 10 and the certified weight sensors 3 are for example provided, at the time of installation, with a unique identification which comprises for example an identification number and an electronic signature. In this case, the devices 10 and the one or more certified weight sensors are coupled to one another and, for example, items of information regarding axle configuration and axle sequence of the motor vehicle 1 and/or of the trailer 5 are stored for example in a data memory of the device 10. Alternatively or in addition, said items of information and further items of information, such as the motor vehicle data KF_D, are made available externally to the motor vehicle 1 and the trailer 5 in a back-end, and can be retrieved as required. For example, one or more spring characteristic curve is also stored in the data memory of the device 10, which spring characteristic curves contain information regarding pressure to weight force and/or spring compression travel to weight force relationships and can be utilized for example in the determination of the axle loads for leaf spring-mounted axles 7 of the motor vehicle 1 or of the trailer 5.

The motor vehicle 1 furthermore has the recording unit 12 which for example permits digital logging of the determined weight forces F_G acting on the respective axles 7 of the motor vehicle 1 and/or of the trailer 5. In this case, the device 10 of the motor vehicle 1, the two illustrated weight sensors 3, the speed sensor 9 and the recording unit 12 are each designed to communicate with one another and transmit or receive the detected measurement signals MS_G, MS_V and the determined weight forces F_G.

The devices 10 and the weight sensors 3 are for example cohesively connected to a vehicle frame of the motor vehicle 1 or of the trailer 5, for example by means of welding. In this context, it is consequently no longer possible for the certified devices 10 to be non-destructively detached from the motor vehicle 1 or the trailer 5. Furthermore, the device 10 and/or the certified weight sensors 3 is for example provided with an anti-tamper seal which is applied by authorized personnel during the installation of said components. Thus, unauthorized dismounting or repositioning of the device 10 and of the certified weight sensors 3 is visible from the outside, whereby a quick external inspection of the system is also possible. Such anti-tamper seals are then, for example similarly to the abovementioned labels and the electronic security key, accessible only to authorized persons working for example at authorized vehicle manufacturers, body manufacturers and installation workshops.

The motor vehicle 1 furthermore has a management unit 15 which, as a higher-level entity, is designed for example to coordinate the data transfer between the certified weight sensors 3, the devices 10 and the recording unit 12. Furthermore, by means of the management unit 15, it is also possible for different motor vehicle-trailer combinations to be configured with regard to the implementation of the flow diagram illustrated in figure 1.

The illustrated system composed of motor vehicle 1 and trailer 5, on which weight sensors 3 and in each case one device 10 are arranged, has for example been installed and programmed at a vehicle or axle manufacturer, as these represent authorized personnel and have access to the required characteristic curves for signal and axle weight. In this case, it is for example possible for cumbersome calibration of the system by means of load simulation to be dispensed with.

For example, a weight sensor 3, as a pressure sensor, is adhesively bonded to and vulcanized into the inside of an airspring bellows or a tire of the motor vehicle 1 or of the trailer 5, and has a dedicated memory in which characteristic curves are already stored. The pressure sensor then monitors for example the pressure of the respective tire, and can consequently also be referred to as tire pressure sensor. For example, the system also comprises multiple tire pressure sensors which, as certified weight sensors 3, permit a determination of a weight force and of an axle load of the respective tire and of the respective axle 7.

In this context, the certified weight sensors 3, for example in the form of tire pressure sensors, are for example arranged internally on an inner side of the tire and monitor rolling behavior of the tire. The rolling behavior in this case provides information regarding a load acting on the axle 7 to which the tire is assigned, and thus permits, for example in the context of an evaluation by way of software, a determination of the weight force F_G and a determination of the axle load. Furthermore, by means of the tire pressure sensor, the monitored rolling behavior can also be evaluated for the purposes of determining and monitoring a profile depth of the tire. Consequently, the certified weight sensor 3 used as tire pressure sensor can also be referred to as profile depth sensor.

The weight sensors 3 have for example electronics which permit processing of the measurement signals MS_G and wireless and/or wired signal transmission. The respective weight sensors 3 of the motor vehicle 1 and of the trailer 5 are coupled in terms of signal transmission to the respective device 10 in wired or wireless fashion. The weight sensors 3 and/or the devices 10 furthermore, for example, have the chassis number stored therein as a unique link to the chassis of the motor vehicle 1 or of the trailer 5.

During the course of periodic inspection, for example in authorized workshops, the system is checked and calibrated on the basis of simulated threshold values by way of pressure and lever travel simulation and with the aid of vehicle scales, in order thereby to ensure reliable functioning. Such inspections are then for example documented on labels or installation plaques, and are for example readily apparent to inspection officials.

By means of the described system, it is for example possible even in the case of changing motor vehicle 1-trailer 5 combinations for the measurement signals MS_G of the at least one weight sensor 3 to be reliably and securely detected and transmitted, and thus for the axle loads of the motor vehicle 1 and/or of the trailer 5 to be monitored. The recording unit 12 permits permanent monitoring of the logged axle loads which, owing to certified weight sensors 3, exhibit assured and certified reliability to a certain extent. Such reliability of the determined axle loads is further supported by the devices 10 and weight sensors 3 which are mounted in or on the motor vehicle 1 or trailer 5 and which are provided with tamper-proof seals and which, both mechanically and electronically, each have unique identification numbers. Replication of and tampering with the measurement signals MS_G and/or MS_V and/or of the determined axle loads is made considerably more difficult by way of such a system.

List of reference signs 1 Motor vehicle 3 Weight sensor Trailer 7 Axle 9 Speed sensor Device 12 Recording unit 14 Coupling Management unit 16 Engine F_G Weight force GE Speed MS_G Measurement signals from weight sensor MS_V Measurement signals from speed sensor K_GS Identifier of weight sensor K_ZE Certified identifier KF_D Motor vehicle data S AE Recording unit memory

Claims (8)

Patent claims

1. A system, comprising: a device (10) for operating a motor vehicle (1), which device (10) is arranged in or on the motor vehicle (1) or a trailer (5), wherein the device (10) is designed to provide motor vehicle data (KF_D) which encompass at least items of information regarding the motor vehicle (1) and/or the trailer (5), to receive an identifier (K_GS) of at least one weight sensor (3),to compare the received identifier (K_GS) with a predefined identifier (K_ZE) for the at least one weight sensor (3),to receive measurements signals (MS_G) of the at least one weight sensor (3) which are representative of an axle load of an axle (7) of the motor vehicle (1) or of the trailer (5),to determine a weight force (F_G) in a manner dependent on the received measurement signals (MS_G) and the provided vehicle data (KF_D) if correlation of the received identifier (K_GS) with the predefined identifier (K_ZE) of the at least one weight sensor (3) has been determined, and to record the determined weight force (F_G) by way of a recording unit (12), the system further comprising at least one certified weight sensor (3) which is coupled in terms of signal transmission to the device (10) and which is arranged in or at a predefined location on the motor vehicle (1) or on the trailer (5) and which is assigned to an axle of the motor vehicle (1) or of the trailer (5), wherein the at least one certified weight sensor (3) is a pressure sensor, which is arranged in a tire of the motor vehicle (1) or of the trailer (5), and wherein the system further having a recording unit (12) which is coupled in terms of signal transmission to the device (10).

2.The system as claimed in claim 1, wherein the device (10) is further designed to receive measurements signals (MS_V) of at least one speed sensor (9) which are representative of a speed of the motor vehicle (1) to determine a speed (GE) of the motor vehicle (1) in a manner dependent on the received measurement signals (MS_V), and to determine the weight force (F_G) in a manner dependent on the determined speed (GE).

3. The system as claimed in claim 1 or 2,in which the pressure sensor is a profile depth sensor, which is arranged in a tire of the motor vehicle (1) or of the trailer (5).

4. The system as claimed in in one of claims 1 to 3, in which the recording unit (12) is a tachograph.

5. The system as claimed in one of claims 1 to 4, in which the device (10) and/or the at least one certified weight sensor (3) are/is coupled cohesively and/or in positively locking fashion and/or in non-positively locking fashion to the motor vehicle (1) or to the trailer (5).

6. The system as claimed in one of claims 1 to 5, in which at least one additional certified weight sensor (3) is arranged in an air-spring bellows of the motor vehicle (1) or trailer (5).

7. The system as claimed in one of claims 1 to 6,in which system comprises at least one speed sensor (9) which is assigned to the motor vehicle (1) or to the trailer (5) and which is coupled in terms of signal transmission to the recording unit (12).

8. The system as claimed in one of claims 1 to 7,in which the motor vehicle (1) has a management unit (15) and the trailer (5) has the device (10), which management unit and device are each designed to communicate with one another in terms of signal transmission when the motor vehicle (1) and the trailer (5) are in a coupled state. -