WO2007099159A1

WO2007099159A1 - Tyre module with piezoelectric converter

Info

Publication number: WO2007099159A1
Application number: PCT/EP2007/051976
Authority: WO
Inventors: Andreas Heise; Stefan Kammann; Markus Neumann
Original assignee: Continental Teves Ag & Co. Ohg
Priority date: 2006-03-02
Filing date: 2007-03-02
Publication date: 2007-09-07

Abstract

A tyre module (4) for recording tyre condition parameters, comprising a piezoelectric converter with a number of supports on which electronic components are arranged, wherein each support is embodied in at least one region as a spring element, or is connected to at least one spring element and the spring element is coupled to piezoelectric material (20) or is made from piezoelectric material (20). The aim of the invention is to provide an improved tyre module (4) with a piezoelectric micro generator (34) for installation within a tyre with a particularly high service life and which guarantees the energy supply to the tyre module throughout the life of the tyre (1) as effectively as possible. Said aim is achieved wherein the support in question itself and/or the electronic components act as seismic mass.

Description

Tire module with piezoelectric transducer

The invention relates to a tire module according to the preamble of claim 1 and its use in a tire pressure monitoring system.

The invention is particularly suitable for determining tire condition variables with an energy self-sufficient system.

In modern motor vehicles are increasingly used devices that detect defects and malfunction of various areas in the vehicle early and report to the driver. This includes, for example, the collection of tire air pressure to avoid defects or accidents due to low tire inflation pressure. In many of the systems already used for this purpose, a tire module is arranged on each wheel, in particular in the interior of the tire. A tire module usually comprises at least one sensor for detecting a tire parameter, in particular the tire air pressure, as well as a transmitting unit and optionally an associated evaluation electronics. The supply of the electronic components with electrical energy can, for example, by a Bat- terie, a microgenerator with piezoelectric element or a transponder coil.

From DE 44 02 136 Al a system for determining the operating parameters of vehicle tires is known in which on a Tragerkorper a sensor unit, an evaluation and a piezoelectric element is arranged, which supplies the other system components with energy. The piezoelectric element has a multilayer structure.

DE 10 2004 046 193 A1 describes a pressure sensor for wireless pressure measurement in a tire and an associated antenna device for transmitting and receiving electromagnetic fields.

From DE 10 2006 003 825 Al a batteryless tire pressure monitoring system is known which detects tire parameters via a sensor, the sensor being connected on the input side to an antenna in order to receive a modulated microwave signal and via a control circuit a part of the modulated microwave signal to convert into a supply voltage. DE 10 2004 031 810 A1 designates a tire control system which generates electrical energy via a piezoelectric element which is arranged inside the tire.

From DE 43 29 591 C2 a device for monitoring the tire air pressure is known, which receives via a sensor, the extent of deformation of the tire during the latency run an electrical impulse and an evaluation determines the extent of deformation.

DE 103 29 700 A1 describes a method which determines the wheel load and the tire air pressure from the tire rotation speed as well as from the latitudinal coil and the deformation via a differentiating sensor.

In DE 10 2004 001 250 B4, a device is disclosed which determines the lateral positions of the wheels from the deformation of the tire during the lane pass in curves via sensor units.

DE 10 2005 000 996 Al provides that a spring element of a tire module is designed as a rod, torsion or leaf spring. At a non-clamped end of the spring element, a seismic mass is arranged, which is acted upon by the rolling of the tire with a pulse. The storage of the seismic mass on the spring element results in a spring mass oscillator, which has an increased efficiency in contrast to conventional piezoelectric energy converters. The vibration is generated by the fact that the tire module moves on a straight path during the unwinding during each load passage, while it moves on a circular path after the lane departure. While - A -

the circular path, the centrifugal force acts on the seismic mass, in Latsch she is ideally power-free. Due to the centrifugal force of the spring-mass oscillator is deflected and strives in Latsch the return to its rest position. There are over- and reverberations, whereby the seismic mass is in motion even during the phases of constant force, ie between the transitions. This is particularly favorable for the electrical energy conversion.

A development of this invention provides that the spring element is clamped in a housing and at least one piezoelectric element is coupled to the spring element in the direction of movement. The piezoelectric element converts the kinetic energy of the spring mass oscillator into electrical energy, which in turn can be passed on to consumers. Advantageously, piezoelectric elements are coupled in each direction of movement of the spring element with the latter, so that electrical energy can be obtained from both piezoelectric elements during oscillation in the respective planes in both deflection directions.

Known microgenerators for the supply of tire pressure monitoring systems based on piezoelectric materials. The piezoelectric effect is based on the effect that electrical charges occur on the surface as certain materials deform. For example, by means of pressure by charge separation, an electrical voltage is usually generated in a ceramic, ie by the pressure exerted, ions move inside, whereby the charge changes in proportion to the applied force. When using a microgenerator to power a tire module mounted inside the tire, it must be ensured that the microgenerator is designed to withstand the stresses at least throughout the life of the tire. It is advantageous if the microgenerator with the other components, such. As the components, a compact module forms.

To achieve a compact design, the piezoelectric element or the piezoelectric elements are mounted directly on the spring element, so that a deflection of the spring element leads to an expansion or compression of the piezoelectric layer, so that at the corresponding contact surfaces, an electrical voltage can be tapped.

Since very high acceleration forces are set at very high speeds, there is the danger in the case of this embodiment that a spring breaks when it is freely clamped. Therefore, it can be provided that in the housing stops in the direction of movement of the spring element are formed, which limit movement of the spring. Advantageously, the stops are designed so that they correspond to the bending line of the spring element or have a lower curvature to the bending line of the spring element. This makes it possible that the spring element rolls on the stops, so that the mechanical loads of the spring element can be reduced.

Additionally or alternatively, it may be provided that the seismic mass is associated with an amplitude limiter in order to to avoid destruction at very high speeds.

Based on this prior art, the present invention seeks to provide an improved tire module with piezoelectric micro generator for mounting inside a tire, which has a particularly long life and as effectively as possible ensures the power supply of the tire module during the entire life of the tire.

This object is achieved by the tire module according to claim 1.

By a leaf spring is meant in general an elastic, flat spring, which can perform bending vibrations. The shape of the surface can be arbitrary. In the simplest case, it is a rectangular leaf spring. But even complicated shapes, for example, produced by punching, are conceivable. As an example, a leaf spring with serpentine base is called.

The invention also relates to the use of the tire module in a tire pressure monitoring system.

Further preferred embodiments of the invention will become apparent from the subclaims and the following description with reference to figures.

During the rotational movement in the direction of rotation 2 of the tire 1 of a motor vehicle, motorcycle, commercial vehicle, plane or bicycle, as shown in FIG. 1, the centrifugal acceleration acts on a tire module 4, which is arranged in the region of the inner tire liner, in particular connected to the inner tire liner. If the tire module 4 is located within the contact patch 6, on the other hand, only the gravitational acceleration is effective. Upon entry and exit in this so-called Laces run, the radius of the tire 1 is reduced by the flattening and there is a Beschleunigungsaushung, as shown schematically in Fig. 2:

The horizontal axis of the coordinate system represents the orbital angle, the vertical axis the radial acceleration. The lathe run 8, which is limited by the latitude and outflow, as well as the centrifugal acceleration 10, provide for two elevations 12 produced during the latitude and outflow.

A tire module 1, which makes use of an acceleration change for energy conversion, inevitably requires a mass deflected by the acceleration according to W = m * a * s (the work / energy results from the product of mass, acceleration and distance). This mass can be represented for example by the component carrier and the components themselves, as shown in Fig. 3. During the action of the centrifugal acceleration 10, the element will deflect due to the applied acceleration. When Latschdurchgang 8 is a back swing. These vibrations are converted by the piezoelectric material into electrical energy.

In Fig. 3 an example moderate tire module 4 is shown schematically. It comprises a carrier layer 14 on which electronic components 16, z. As sensors, in particular a pressure sensor, evaluation, transmitting and / or receiving devices for the exchange of control and data signals, memory, a second energy source, etc., and piezoelectric material, for. B. in the form of a piezoelectric element 20 on a piezo-active surface, are arranged. The carrier layer 14 may, for. Example, a glass fiber reinforced epoxy resin plate (FR4 or FR5), a metal carrier layer or carbon, glass fiber or ceramic.

The tire module 1 is arranged in such a way inside the tire 1, in particular on the inner liner 22, that the carrier layer 14, which is clamped on one side in a suitable clamping 18, as a kind of spring element in the radial direction of the tire 1 can oscillate, in FIG 3 indicated by the two directional arrows. A conceivable embodiment of the arrangement of the tire module 4 in the tire 1 is shown in FIG. 3b. Here, the electronic components 16, which are arranged at the non-clamped end of the support layer 14, act as a seismic mass. That is, the piezoelectric element 20 is disposed in the tire 1 so as to convert changes of the radial acceleration (direction and / or absolute value) into electric energy.

In a preferred embodiment, the carrier layer 14 is a printed circuit board, which serves as a component carrier. The piezoelectric material 20 is applied directly to the component carrier.

In the processing of piezoceramics, for example as trimorph 23, ie a system of two piezoelectric, in particular piezoceramic, components and a passive intermediate layer 14, have been used as support materials (passive intermediate layer) carbon fibers (carbon), uniaxial glass fibers or metals. 4a shows an example of a conventional application according to the prior art with a carbon carrier layer 24. A preferred embodiment is now to replace this carrier layer 14 by a component carrier 26, for example a printed circuit board, and the piezoceramic 20, As shown in Fig. 4b, apply directly to the electronic components 16 bearing material. The printed circuit board 26 can be made, for example, from FR4 or FR5 (high-temperature FR4) (glass fiber-reinforced epoxy resin). The piezoelectric ceramic 20 may be designed as lead zirconate titanate (PZT).

In addition to the arrangement as Trimorph 23 are all other conceivable arrangements, eg. Example, as a monomorph, a system of piezoelectric components 20 and a passive layer, or as a multimorph, a system of many piezoelectric components 20, of piezoelectric material, in particular piezoceramic material or piezo film (eg., Polyvinylidenfluorid, PVDF) on a carrier layer, in particular printed circuit board, possible.

Advantage of this arrangement is that an electrical circuit of electrical components with a piezoelectric ceramic are positioned together on a component carrier 26. This results in a compact and closed system, since the contacting of the piezoelectric material 20 can take place directly over the carrier layer 14. There is no need to handle any additional (piezoelectric) element. In the tangential direction to the tire 1, an acceleration transition, as shown in FIG. 5, likewise takes place on entering and leaving the lug 6, on a tire module 4 arranged in the region of or on the tire innerliner (s) 22 three overlapping effects results:

1. the compression and elongation of the innerliner material,

2. the tilting movement in the transition from or into the rotational movement, and

3. the gravitational acceleration.

The horizontal axis represents the orbital angle, whereas the vertical axis represents the tangential acceleration.

Also, this acceleration change can be used by a, as shown in Fig. 3, beispielsgemaßes tire module 4 for energy. For this purpose, the tire module 4 is arranged in such a way inside the tire 1, that the carrier layer 14, which is clamped on one side, as a kind of spring element in the tangential direction can oscillate, as indicated in Figs. 6 and 7 by the two directional arrows. This means that the piezoelectric element 20 is arranged in the tire 1 in such a way that it converts force effects in the tangential direction into electrical energy.

6 shows an embodiment for the use of the tangential force action in an unstable arrangement, Fig. 7 shows an embodiment for the use of the tangential force in a pendulum-like arrangement.

For the energy conversion in the tire 1, it is also possible to use a microgenerator which makes use both of bending changes (for example the deformation or deformation of the inner tire 22 in the case of a lane pass 8) and of acceleration changes. Previous systems use either the changes in the bending radius on the tire innerliner 22 or the acceleration change when entering / leaving the lug 6. If you use both effects at the same time, a higher effectiveness can be achieved.

Two embodiments of a tire module 4 with a microgenerator, which converts both deformations and acceleration changes into electrical energy, are shown schematically in FIGS. 8 a, 8 b and 9. By way of example, the tire module 4 is fastened to the tire innerliner 22 by at least two attachment points (see FIGS. 7b and 1) in such a way that deformation or bending of the carrier layer 14 of the tire module 4 takes place in the case of the lane passage 8, as shown in FIG. 1 is shown schematically, wherein the bend is limited by the Auslenkungsanschlage 30.

For this purpose, the positions of the fasteners 28 of the tire module 4 on the inner liner 22 are preferably spaced apart in the running direction 2 of the tire 1. The carrier layer 14 is clamped or fastened at two ends in the clamps 18. In the two outer regions, the support layer 14 is designed such, for example, by the material thickness and / or the basic shape, for. B. Schlangenlinienformig in Fig. 8 and 9) that they bending vibrations in the radial direction of the tire 1 (indicated by the directional arrows in Fig. 8b). In this case, the electronic components 16 interact with the component carrier 26 as a seismic mass. The electronic components 16 are preferably arranged in the middle region of the tire module 4.

The piezoelectric material 20 is arranged on the carrier layer 14, in particular in the outer regions, so that electrical energy is generated both by direct deformation of the carrier layer 14 during the sheet pass 8 and by changes in acceleration during the oscillations during the sheet pass 8. In a preferred embodiment, the carrier layer 14 is a printed circuit board (a component carrier 26). The piezoelectric material 20 is thereby, as already described above, directly on the component carrier

26 applied.

In the described microgenerators, among other things, a change in the acceleration is used to generate energy. It is a vibrating system. Such a system generally needs to be protected from excessive deflections. For this purpose, usually Auslenkungsbegrenzende stops 30 are provided in the housing 32, as shown in Fig. 8b. The microgenerator in the tire module 4 is to be deflected several tens of millions of times, in a conventional system with stops 30 this would lead to a large mechanical wear.

To prevent this, the tire module 4 can be damped in its vibration. For example, the tire module 4 can be stored in a liquid such that it can only move against a resistance. It creates a low pass with damping, ie low-frequency vibrations are transmitted to the tire module 4, high-frequency vibrations, as they can occur at very fast driving, are attenuated. The system may be designed such that, after a certain speed, the deflection stops 30 in the housing 32 are no longer touched.

The damping can also be realized by other suitable methods, for example pneumatically or with the aid of an elastomer. A pneumatic damping can be realized by an air volume, which is compressed at each oscillation. For this purpose, the printed circuit board with a (almost) air-impermeable layer, such as a film or a suitable paint or plastic layer are coated and thus separate the upper and lower chamber from each other, as shown in FIG. 11.

In a deflection is then worked against the compressed air volume. Another conceivable possibility is to use pneumatic damping elements. An elastomer may be embodied as a compressible elastic plastic. The deflection limits shown in FIG. 8b can be made, for example, of an elastomeric material. Thus, no hard stop, but a "gentle" Auslenkungsbegrenzung.

The intended microgenerator 34 may be meandering (Figures 10c and d), spiral (Figure 10b), or simply straight (Figure 10a), but may also be a polygonal one (Figures 10a, b, c). round or oval ("tablet" or "candy", Fig. 10 d) have basic shape. In this way, the length of the vibrating elements is increased, the Reso- nanzfrequenz the arrangement is significantly reduced and thus increased the effectiveness especially at low speeds.

A tire module 4 described above can use, in addition to the micro-generator 34, a second energy source in order to be able to function even when stationary and / or to be able to store data. This may be a battery or an LF source (low frequency source), e.g. B. 125 kHz, be. This results in the possibility of supplying energy to the tire module 4 both while driving and when stationary (eg in production). When driving, the power is supplied by the microgenerator 34, in the state, the power can be supplied via a low-frequency (LF) field. The LF-FeId can also transmit data to the tire module 4 in addition to the power supply.

A combination with RFID 36 (Radio Frequency Identifier) is also possible. Here, the known RFID technology (antenna and RFID chip with EEPROM 38) is used in combination with the tire module 4, as shown in FIG. With RFID, data can be read from memory or written to memory. This memory is identical to the data memory that the tire module 4 uses in driving mode (microgenerator mode). Via RFID, data can thus be written in the tire 1 and read from the tire 1. This data transmission can be used both during tire and vehicle production as well as in operation, for logistics or for diagnosis in service. Both RFID and the unit controlling the tire module 1 use the same memory. An advantage here is that the RFID technology does not require an external power supply. forces. This predestines this technique for combination with a microgenerator fed 34 tire module 4, which only works while driving.

The micro-generator 34, which fully or partially supplies voltage to the tire module 4, can be used to detect the length of the lug 6 (or the ratio between the time of the lane pass 8 and the cycle time), with the microgenerator 34 being used as the litter recognition signal generator. The microgenerator 34, which also serves as a sensor, can thereby use radial or tangential changes in acceleration, deformation of the tire 1 or a combination of both. Preferred is a microgenerator 34 based on a piezoelectric transducer as described above.

The time of the lane pass 8 may be determined with an acceleration sensor arranged in the tangential or radial direction of the tire 1. For example, a piezoelectric acceleration sensor may be used. Due to changes in acceleration that occur during latitude and exhaust, the vibrationally mounted seismic mass (test mass) is excited to vibrate. This kinetic energy is converted by a piezoelectric element 20 into electrical voltage. It is possible to determine the times between the voltage spikes which occur between the latent and outgoing currents. From the time intervals, the latency runtime and the orbital period can be determined.

Another possibility is the deformation (or elongation) of the tire inner liner 22, especially the kink in the Entry or exit in the laces, to measure and from this the time of the latency run (and the rotation time) to determine. This can also be done with the aid of a piezoelectric material 20, which is arranged on a region in the tire 1, which is deformed during the sheet pass 8. Since the tire 1 is deformed during the latitude and latitude exiting, charge separation takes place in the piezoelectric material 20, which can be tapped off as electrical voltage. The times between these voltage spikes can be determined. From the time intervals, the Latschzeit and the orbital period.

The information and data described above, e.g. B. Latschzeit and cycle time, are then as part of the transmission protocol from the tire module 4 to the vehicle electronics, z. For example, a central unit of the tire monitoring system in the vehicle is sent. The processing of the data can be done both in the tire module 4 and in the vehicle electronics.

The tire module 4 determines an indicator for the latitudinal coil or the ratio of latitudinal coil to tire circumference of a tire 1, in this case, for example, a quotient of lathe / circulation time can be measured. The indicator can be transmitted from the tire module 4 to an evaluation unit.

The determined ratio of latschzeit to orbital time can be used for one or more of the following system tasks, optionally, the information regarding the Latschzeit / Lat snake by information about the tire pressure, which z. B. with one, in particular in the rice integrated, pressure sensor is determined, supplemented or combined:

1. Assignment of the tire modules to the individual positions (autolocation) by means of "dynamic axle load distribution." Depending on the driving dynamics, corresponding wheel loads occur and, accordingly, different latitudes depending on the driving situation. The lashing on the left side is therefore longer and the lashing on the right side shorter For example, during a braking operation, the lash increases in the front Thus, occur during cornering or during acceleration or braking different Latschlängen on These can be detected and used.

2. Load-dependent pressure warning becomes possible (more weight will increase the latitude, meaning that more pressure is needed in the tire). Tire manufacturers recommend adjusting different air pressures depending on the load. Usually, the subdivision is done so far in two or three stages (empty, partially loaded, fully loaded). Here you can use an intelligent model, which z. B. additionally taken into account the route or the vehicle speed (pressure warning at high load and insufficient air pressure for example, takes place only after a certain distance or from a certain speed).

3. Rolling movements can be detected and prevented by communication with the ESP control unit. When a vehicle staggers, the dynamic wheel loads change. This can - 1 !

detected by a Latschlängenmessung and used for other systems.

4. The individual wheel loads can be recognized and used by other systems of the vehicle. If the characteristics of a tire are known, one can in principle determine the wheel load with the aid of the latitudinal length and the tire pressure. The wheel loads can z. B. for the optimization of the braking system (EBV - electronic brake distribution) can be used. Furthermore, the spring-damper effects of modern suspension can be adjusted. In known wheel loads, the chassis can be adapted to the conditions, which means more comfort and safety for the driver. Likewise, the steering can respond to the individual wheel loads (or the loading state of the vehicle). Thus, comfort and handling can be improved with loaded vehicles.

5. Uneven surfaces can be detected and used by other systems of the vehicle (eg landing gear or brakes).

6. Early detection of aquaplaning (or driving on slush etc.) becomes possible (floating of a wheel is detected). Vehicle systems can respond to this and make a control / regulation.

7. Wheel load detection is possible because the latitudinal length is directly related to the wheel load. The Radlasterkennung can z. B. can be used to automatic headlamp leveling, which previously necessary sensors can then be omitted. 8. Use of the latency signal for a roll-over protection and avoidance (roll-over protection), since an impending take-off of one or more wheels is detected.

9. Detection of lifting (or imminent lifting) of a vehicle wheel off the road.

10. Redundancy of the air pressure sensor. So far, the plausibility of the pressure value can not be understood. If the latent data is still available as the second information, a "hanging" pressure sensor or a pressure sensor that detects a completely wrong value can be detected.

LIST OF REFERENCE NUMBERS

1 tire

2 direction of rotation

4 tire module

6 laces

8 laps pass

10 centrifugal acceleration

12 voltage spikes

14 carrier layer

16 electronic components

18 clamping

20 piezoelectric elements / material

22 inner liners

23 trimorph

24 carbon backing

26 component carrier (printed circuit board)

28 attachment

30 deflection stop

32 housing

34 microgenerator

36 RFID

38 RFID chip

Claims

claims

A tire module (4) for detecting tire condition variables with a piezoelectric transducer having a number of support means on which electronic components are arranged, wherein the respective support means is formed in at least one area as a spring element or is connected to at least one spring element, and wherein Spring element with piezoelectric material (20) is coupled or consists of piezoelectric material (20), characterized in that the respective carrier means itself and / or the electronic components act as a seismic mass.

2. Tire module (4), in particular according to claim 1, for detecting tire condition variables with a piezoelectric transducer having a number of support means on which electronic components are arranged, wherein the respective support means is formed in at least one area as a spring element or with at least one spring element is connected, and wherein the spring element with piezoelectric material (20) is coupled or consists of piezoelectric material (20), characterized in that the carrier means is liquid-damped.

3. tire module (4) according to claim 2, characterized in that the spring element is liquid-damped.

4. Tire module (4) according to one of claims 1 to 4, characterized in that at least one end of the spring element is clamped.

5. tire module (4) according to one of claims 1 to 5, characterized in that the tire module (4) on an inner side of the tire (1), in particular in a region of the tire (1), which deformed at a Laces pass (8) is fixed.

6. tire module (4) according to one of claims 1 to 6, characterized in that it is arranged in the tire (1) so that the vibration direction of the seismic mass is substantially in the radial direction of the tire (1).

7. Tire module (4) according to one of claims 1 to 6, characterized in that it is arranged in the tire (1) so that the vibration direction of the seismic mass is substantially in the tangential direction of the tire rotation.

8. tire module (4) according to one of claims 1 to 8, characterized in that this in the tire (1) is arranged so that in addition to the use of acceleration changes to the energy conversion and the deformation of the tire (1) at Laces pass (8), which is transmitted to at least parts of the tire module (4) is used for energy conversion.

9. tire module (4) according to one of claims 1 to 9, characterized in that the spring element is designed as a leaf, rod or torsion spring.

10. tire module (4) according to one of claims 1 to 10, characterized in that the carrier means is a carrier layer (14), in particular a printed circuit board (26).

11. Tire module (4) according to one of claims 1 to 11, characterized in that the piezoelectric material (20) is applied directly to the spring element, in particular to the at least one region formed as a spring element carrier means.

12. tire module (4) according to one of claims 1 to 12, characterized in that the piezoelectric material (20) in each case in one or more layers one or two sides is applied to the spring element.

13. Tire module (4) according to one of claims 1 to 10, characterized in that the piezoelectric material (20) is a piezoelectric ceramic, in particular lead zirconate titanate (PZT), or a piezoelectric film, in particular of polyvinylidene fluoride (PVDF).

14. tire module (4) according to one of claims 2 to 14, characterized in that the carrier means is designed as a leaf spring, at the non-clamped end of the electronic components are arranged.

15. Tire module (4) according to one of claims 1 to 11, characterized in that the carrier means in two areas as a spring element, in particular as a leaf spring is formed, between which the electronic components are arranged, and is clamped at two opposite ends.

16. tire module (4) according to claim 16, characterized in that a deformation of the support means in Latschdurchlauf (8) is achieved in that the clamped ends of the carrier along the running direction of the tire (1) in the region of the tread fasteners (28) ,

17. tire module (4) according to one of claims 1 to 17, characterized in that a suitable pneumatic or an elastomer for the vibration damping of the seismic mass is provided.

18. tire module (4) according to one of claims 1 to 18, characterized in that this comprises, in addition to the piezoelectric transducer, a second means for supplying energy, in particular in Shape of a battery and / or by transponder technology via an electromagnetic field.

19. Tire module (4) according to one of claims 1 to 19, characterized in that it is equipped with a means for radio identification (RFID).

20. Tire module (4) according to one of claims 1 to 20, characterized in that it comprises a data memory.

21. tire module (4) according to claim 21, characterized in that the data memory comprises a transmitting and receiving unit for wireless data transmission.

22. tire module (4) according to any one of claims 1 to 22, characterized in that this is a characteristic which is a measure of the latitudinal coil of the tire module (4) associated with the tire (1) determined.

23. Use of a tire module (4) according to one of claims 1 to 23 in a tire monitoring system.

24 tire monitoring system with a tire module (4) according to one of claims 1 to 23, characterized by a central unit and a number of tire modules (4), which communicate with a central evaluation unit via control lines or by means of a wireless transmission technology.

25. A method for operating a tire module (4) according to one of claims 1 to 23, in which a deformation of at least one elastic bending region, which is coupled to a piezo elastic material (20) or consists of a piezoelectric material (20), for generating electrical energy is used, and the deflection of at least one of the elastic bending areas is limited to protect against excessive bending.