Vehicle wheel with measuring and monitoring device for a vehicle - Patents.com

Abstract

The present invention relates to a vehicle wheel and an associated monitoring device, comprising a rim part 203, a disc part and a measuring device 210 with at least one measuring sensor for detecting forces acting on the vehicle wheel. In order to provide the measuring device in a simple manner and to make it possible to determine the dynamic and static load forces on the vehicle wheel during driving operation, according to the invention a metal strip 111 is attached to the outside of the rim part 203 by adhesive connection and a measuring device is assigned to the metal strip, the measuring device 210 comprising a bending strut provided with at least one measuring sensor and connected to the metal strip at two spaced apart fastening zones, or the measuring sensor comprises several differently oriented strain gauges connected to the metal strip for local detection of deformations of the metal strip between the fastening zones.

Description

[Technical field]

[0001] The invention relates to a vehicle wheel having a rim part with a rim flange, a rim shoulder and a rim well base for supporting a tire, a disk part having a hub connection flange with bolt holes and a transition part with ventilation holes and connected to the rim part for non-rotatably fastening the vehicle wheel on a vehicle, and a measuring device fastened co-rotatably to the vehicle wheel, having at least one measurement sensor for detecting forces acting on the vehicle wheel and having a transceiver coupled to the measurement sensor for transmitting load data detected by the measurement sensor to a component outside the vehicle wheel, in particular a vehicle-side monitoring device having an evaluation device. The invention further relates to a monitoring device for a vehicle having several vehicle wheels, at least one vehicle wheel having a measuring device with a measurement sensor and a transceiver coupled to the measurement sensor and a vehicle-side evaluation device for measurement signals of the measurement sensor. [Background technology]

[0002] In particular, heavy goods vehicles and regular goods vehicles are subject to weight restrictions on certain roads. To determine the load capacity within the vehicle, weight sensors may be permanently installed between the vehicle chassis and the vehicle's loading area. These respective load sensors are for limited detection of the weight on the loading area of ​​the goods vehicle. These sensors do not provide any other data about other vehicle conditions, and are not designed or provided to detect other conditions such as mass distribution, temperature, tire pressure, wheel camber, etc. Such loading conditions and other detected operating conditions may affect how the vehicle systems react during the driving mode.

[0003] From WO 2017 / 048762 A1 it is known to fasten a monitoring device with a load detection device to the outer periphery of the rim part of a vehicle wheel in such a way that the sensor is arranged protected from environmental influences in the pressure-loaded interior of the tire. The load detection device has a strain gauge, which is for determining the impact load acting on the vehicle wheel under both static and dynamic conditions, for which the forces occurring during the rotation of the vehicle wheel are determined as sinusoidal signals and the wheel load is determined by the recorded maximum value. Static loads can also be detected, for which the rotational position of the monitoring device relative to the wheel contact area is also detected in order to determine the load, if necessary, by correlating the measurement signal of the strain gauge with previously recorded measurement data under different loads. In the known solution the housing of the monitoring device is fastened, preferably by gluing, to the rim well base and has a lower part that curves according to the curvature of the well base. Additional sensors can be arranged in the housing to detect various vehicle conditions such as wheel clamping force, wheel load, axle load, mass distribution, ambient temperature, wheel temperature and tire pressure. The information obtained through the sensor can be used in various systems such as, but not limited to, Traction Control System (TCS), Anti-lock Brake System (ABS), Electronic Brake Force Distribution (EBD), Anti-roll Stabilizer (AAR), Collision Prevention Brake System (CMBS), Collision Prevention Brake System (CMB), All Wheel Drive (AWD), Tire Pressure Management System (TPMS), Tire Wear and Damage Control Logging, among others. In order to permanently supply energy to the monitoring device, a piezoelectric element and an energy generating circuit are provided in the housing to convert the energy generated by the vibration of the piezoelectric element into electrical energy, which can be stored as required.

[0004] From WO 2021 / 048761 A1, a modified variant of a monitoring device for vehicle wheels is known, in which the housing has two fastening zones spaced apart from each other in the circumferential direction, a bending strut is arranged between the fastening zones as an essential element of the monitoring device, and a measurement sensor, in particular a strain gauge, is arranged directly on the bending strut in order to determine the load forces acting on the respective vehicle wheel via the deformation of the bending strut. To fasten the housing, an adapter plate with a threaded hole can be glued to the outer periphery of the vehicle wheel, or a fastening pin or a fastening screw is fastened to the outer periphery of the vehicle wheel, whereby the fastening zones interact. With this design, the actual measurement sensor can be relatively easily replaced and the corresponding housing can be mounted on vehicle wheels with different wheel geometries.

[0005] Also known from US 2021 / 0023893 is a measuring device and a vehicle wheel, by means of which the dynamic load on the vehicle wheel is determined. Here, however, the sensor is not arranged on the actual rim, but on the disk part of the vehicle wheel, i.e. on the spokes of the disk part or on the annular part of the disk part, which includes, for example, the air vents. The actual sensor preferably consists of a capacitive sensor having two sensor surfaces separated from each other by a dielectric material, the sensor being arranged on a sensor sheet on the surface of the disk part. When the vehicle wheel deforms due to different loads, the two sensor surfaces also deform, whereby an electrical signal is generated that is used to determine the wheel load. The magnitude of the signal depends on the angular position of the sensor relative to the wheel contact area and is greatest when the sensor is in a position above the wheel contact area. The document refers to empirical data, according to which there is a linear relationship between the tire pressure and the actual measurement signal. Summary of the Invention [Problem to be solved by the invention]

[0006] The object of the present invention is to create a vehicle wheel which can be equipped with a measuring device in an even simpler way in order to be able to determine the dynamic load on the vehicle wheel during driving operation and also the static load forces by means of suitable measuring devices. [Means for solving the problem]

[0007] To solve this problem, according to a first solution concept according to the invention: - a metal strip is attached to the radially outer side of the rim section, and at least one measuring sensor is assigned to the metal strip; the metal strip has a lower side and an upper side and at least one subsection having a constant thickness in the circumferential direction between the lower side and the upper side, - the underside of the metal strip is connected to the outside of the rim part along the section by means of an adhesive connection; - the measuring device has a bending strut provided with at least one measuring sensor, which strut is connected to the metal strip in two fastening zones spaced apart from each other in the circumferential direction of the rim part for local detection of deformation of the metal strip between the fastening zones, - the metal strip has a circumferential length of the vehicle wheel that is greater than the distance between the fastening zones from each other It is proposed that:

[0008] The invention proposes a metal strip with fastening elements, which is fastened as an additional element to the rim of the vehicle wheel and then fastens a measuring device with a measuring sensor, preferably removably, to the fastening elements of the metal strip. By inserting the metal strip, there is a high degree of flexibility in terms of adaptation to different wheel geometries. The sensor does not measure directly on the surface of the rim part, but only indirectly via the deformation of the metal strip. A reliable connection between the metal strip and the surface of the actual vehicle wheel can be realized, for example, preferably via a suitable adhesive connection.

[0009] In the above-mentioned first solution concept, it is particularly advantageous if the fastening zone consists of two anchor pins or anchor nuts which are fastened circumferentially offset to one another on the cover side of the metal strip, which can preferably be welded or brazed to the metal strip.

[0010] The metal strip can preferably be partially provided with recesses between the fastening zones, which is particularly advantageous if the recesses are mounted symmetrically relative to the fastening zones, whereby measurement deviations due to the recesses can be avoided.

[0011] According to one solution variant, the metal strip can only partially extend over the periphery of the rim part. However, according to an alternative solution variant, it can prove to be advantageous if the metal strip extends completely over the periphery of the rim part. In particular, in the second solution variant, it is particularly advantageous if the metal strip has at least two subsections with different strip widths transverse to the circumferential direction.

[0012] According to all the above-mentioned variants of the first solution concept, it is particularly advantageous if the measuring device is provided with a housing and an electrical circuit which is arranged in the housing together with the transceiver, the bending post and the measuring sensor, and which is preferably fastened to the fastening zone as a unit in a separable and replaceable manner.

[0013] According to a further variant of the first solution, the metal strip of one measuring device may comprise several sections, preferably a thinner metal strip strip constructing the outer section of the perimeter and a thicker metal sheet strip constructing the inner section of the perimeter, the bending strut being made up of a central metal sheet strip fixed between the inner ends of the metal sheet strips facing each other, preferably the measuring sensor being fixed on the underside of the central metal sheet strip. Preferably, in this variant, the outer metal sheet strips are fastened by adhesive connections to the outside of the rim section. Furthermore, preferably, the outer sections of each metal strip are fastened along their entire perimeter extension and the inner sections are fastened to the outside of the rim section along a part of the perimeter extension, preferably the metal sheet strip constructing the inner section of the perimeter comprises a step of reducing the sheet thickness on the lower side, moving the lower side away from the outside of the rim section.

[0014] With this arrangement, the adhesive of the adhesive connection transfers the displacements of the glued fixing points on the thin metal strip to the thicker metal sheet strip, which in turn transfers the displacements to the central metal strip strip forming the bending strut and equipped with the measuring sensor, generating a deformation signal for the bending strut. The strain gauges forming the measuring sensor are preferably installed only on the bottom surface of the bending strut, where both strain forces (bending and axial) are summed. It is particularly advantageous if the measuring sensor is designed as a measuring surface with four strain gauges, of which two strain gauges are oriented in the circumferential direction and two further strain gauges are oriented transversely to the circumferential direction, preferably parallel to the wheel axis.

[0015] According to the most preferred variant of using the aforementioned measuring devices, two measuring devices each having a measuring sensor on its bending strut are positioned offset from each other in the circumferential direction, the distance of the two measuring sensors relative to each other in the circumferential direction being preferably 40°. According to this embodiment, it is advantageous if the measuring sensor is connected by a cable connection to an electronic circuit, a transceiver and a power supply, which preferably forms a component or additional part of a tire pressure measuring device (TPMS) assigned to the vehicle valve.

[0016] In order to solve the above mentioned problem, according to a second alternative solution concept according to the invention, - a metal strip is attached to the radially outer side of the rim portion and at least one measuring sensor is assigned to the metal strip; the metal strip has a lower side and an upper side and at least one subsection having a constant thickness in the circumferential direction between the lower side and the upper side, - the underside of the metal strip is connected to the outside of the rim part along the section by means of an adhesive connection; - the measuring device has at least one measuring sensor connected to the metal strip with some of the strain gauges oriented differently for local detection of deformations of the metal strip, - the metal strip has a circumferential length that is greater than the partial circumferential length covered by the strain gauge of the measuring sensor It is proposed that:

[0017] Here, too, and according to the invention, a metal strip is used that is glued to the surface of the rim of the vehicle wheel. However, the measuring device cannot be replaced here, but the actual measuring sensor is arranged directly on the metal strip in order to detect the deformation of the metal strip locally. Nevertheless, the advantage remains that the metal strip that is fastened to the rim of the vehicle wheel as an additional element offers a relatively high degree of flexibility in terms of adaptation to different wheel geometries, so that the created measuring device that is arranged on the metal strip can be adapted to different wheel geometries.

[0018] According to an advantageous embodiment, the measurement sensor with the strain gauge is covered by a plastic cover, in particular a plastic strip which is glued onto the upper side of the metal strip.

[0019] It is particularly advantageous if the measurement sensor is designed as a measuring surface with four strain gauges, of which two strain gauges are oriented in the circumferential direction and two further strain gauges are oriented transversely to the circumferential direction. It is also advantageous if the measurement sensor is connected by a cable connection to an electronic circuit, a transceiver and a power supply, which forms a constituent or additional part of a tire pressure measuring device (TPMS) assigned to the vehicle valve.

[0020] In all variants, it is particularly advantageous if at least two measuring sensors distributed around the periphery of the rim part and operating independently are positioned offset from each other in the circumferential direction, the distance of the two measuring sensors relative to each other in the circumferential direction being preferably at least 20°, in particular 22.5° in some variants or 40° in different embodiments. A corresponding arrangement makes it possible to measure the static load on all vehicle wheels mounted on the vehicle when the vehicle is stationary, independent of the rotational angular position of the vehicle wheels. The latter is based on the finding that, at a certain rotational angle, if only one measuring sensor is present per vehicle wheel, it is not possible to mathematically determine the static load from the measured values. The load measured by the sensor depends on the angular position (rotational angle) α of the sensor's position relative to the wheel contact area. The basic mathematical approach is that, assuming a constant weight load L, a constant internal tire pressure p and a constant ambient temperature T during a 360° rotation, the sensor value e determined by the sensor is a periodic function that depends on the rotational angle α during a complete wheel revolution. Essentially, the mathematical approach is based on the formula e = f(α, L, T, P) If it is assumed that there is a linear relationship between the tire pressure and temperature and the sensor value set by the sensor, this function can be mathematically divided into several components, namely: e=e 0 (T,P+g(P)*L*c(α)

[0021] With this mathematical assumption, -e 0forms part of the weight load independent function, - c(α) forms part of the proportional dependence on the weight load as a periodic function. c(α) corresponds to a periodic function that ideally repeats with every revolution of the wheel, which is why the following applies: c(α)=c(α+2kπ) - g(P) is a scaling factor that reflects the pressure-dependent effect of the stiffness of the wheel-tyre system.

[0022] These formulas and conditions are useful when determining the static load due to gravitational forces. The necessary conditions for this are, among others, the ratio coefficient e 0 This is done in a suitable calibration method to determine the deviation coefficients of the respective curves as a function of temperature and tire pressure. In a further calibration method, c(α) is then determined by a number of measurements, for which corresponding measurements are performed at different angular positions of the sensor.

[0023] After the individual coefficients have been suitably determined by a calibration method, the dynamic weight load is calculated according to the formula: L=e amp / k(P) whereby the following applies to the dynamic measurements: e amp =e max -e min k(P)=g(P)*(c(α) max -c(α) min )

[0024] Therefore, if the vehicle wheel calibration reference curves are available through calibration for the respective internal tire pressures, it is not necessary to know the rotation angle and temperature to determine the dynamic load.

[0025] The static weight load of each vehicle wheel can be determined by the following formula:

number

[0026] In all designs, the metal strip can consist of stainless steel, light alloys, metal alloys or high-grade steel. The metal strip must have a constant thickness of 0.03 mm to 0.25 mm, in particular 0.05 mm to 0.2 mm, especially in the section where the measuring sensor is also arranged. The metal strip must furthermore have a width of more than 15 mm in the section.

[0027] The connection between the metal strip and the surface of the rim part is preferably made via an adhesive bond, the adhesive having an elastic modulus of at least 50 MPa, preferably more than 200 MPa, particularly preferably more than 450 MPa, the thickness of the adhesive in the area of ​​the adhesive connection being preferably less than 0.25 mm, most preferably less than 0.125 mm.

[0028] The adhesive is preferably selected from acrylic, cyanoacrylate or silicone based adhesives. The adhesive can in particular be applied to the underside of the metal strip and to both sides of the outer rim portion. The thickness of the adhesive can be approximately equal to the thickness of the metal strip of the partial section or can be greater than the thickness of the metal strip of the partial section.

[0029] The invention also relates to a monitoring device for a vehicle with several vehicle wheels, at least one of which is designed according to one of the solution approaches of the invention and is likewise provided with a metal strip, to which a measuring device with a measurement sensor and a transceiver coupled to the measurement sensor are assigned, and a vehicle-side evaluation device for the measurement signals of the measurement sensor is available. According to the invention, the monitoring device is designed and formed in such a way that the dynamic load in driving operation and the static load in the stationary state of the vehicle on the associated vehicle wheel can be determined from the measurement signals of the measurement sensor, in order to determine the dynamic load by the evaluation device, a measurement signal amplitude between a measured maximum signal value and a measured minimum signal value in one revolution of the wheel is determined and compared with an amplitude value from a vehicle wheel calibration reference curve for determining a deviation factor, in order to determine the static load, a rotation angle between the sensor position and the wheel contact position is determined, in which the measured signal values ​​are compared by the evaluation device with reference values ​​from the vehicle wheel calibration reference curve for the same rotation angle, and several vehicle wheel calibration reference curves for different temperatures and internal tire pressures are stored in the evaluation device. The continuously determined measured values ​​during the dynamic measurement of the respective vehicle and weight load are calculated based on a load-independent element e 0 It is particularly advantageous to be able to determine, via which the displacement of the curve at different temperatures and tire pressures is then determined based on a previous calibration, which is required for the static load calculation. In the preferred conventional calibration, the static load is calculated independently of the pressure and temperature, by a load-independent factor e 0 can be determined from the signal value via:

[0030] Further advantages and designs of the invention result from the following description of exemplary embodiments which are illustrated diagrammatically in the drawings. [Brief description of the drawings]

[0031] [Figure 1] FIG. 1 shows a schematic plan view of a highly simplified, not to scale, vehicle wheel with an attached measuring device according to a first exemplary embodiment and a diagrammatically shown tire pressure valve for a tire pressure control system (TPMS). [Diagram 2] 1 shows a measurement device according to a first exemplary embodiment in a schematic top view; [Diagram 3] FIG. 2 shows the measuring device according to FIG. 1 in a schematic detailed cross-section through the rim and the measuring device. [Figure 4] 3 shows a measurement device similar to that of FIG. 1 and FIG. 2 according to a second exemplary embodiment. [Diagram 5] 3 shows a measuring device according to a second exemplary embodiment in a perspective view as mounted on a rim portion; [Figure 6] 6 shows the measurement device of FIG. 5 with the housing removed. [Figure 7] FIG. 7 shows a schematic simplified top view of the measuring setup of FIG. 6. [Figure 8] 1 is a highly simplified schematic diagram showing the relationship between rotation angle and wheel contact area. [Figure 9] 2 shows a highly simplified example of a diagram showing periodic measurement signal values ​​of several measured wheel revolutions, divided into different parts; [Figure 10] 1, there is shown diagrammatically a measuring device arrangement according to a further alternative third embodiment, and a diagrammatically illustrated tire pressure valve for a tire pressure control system (TPMS). [Figure 11] The measuring device arrangement according to FIG. 10 is shown in a cross-sectional side view of a vehicle wheel. [Figure 12] 1 shows a schematic diagram of a measuring device according to a third embodiment in an enlarged-scale side view; [Figure 13] The measurement setup is shown diagrammatically in a bottom view. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0032] In Fig. 1 the vehicle wheel is generally indicated by the reference number 1, which, as known per se, comprises a disk part 2 and a rim part 3. The vehicle wheel can be constructed in one piece from cast parts made, for example, from a light alloy, or the disk part 2 and the rim part 3 are manufactured separately and then connected to each other, preferably with a welded joint, to form the assembled vehicle wheel. The disk part 2 serves functionally for the non-rotatable fastening of the vehicle wheel 1 to the hub of a vehicle (not shown). The rim part 3 is functionally used for supporting a tire (not shown), which is made from plastic and inflated to an internal pressure recommended by the vehicle manufacturer, only the tire being in contact with the ground. For supporting and mounting the tire, the rim part 3 has, as known per se, two rim flanges 4, two rim shoulders 5 and a multi-stage rim well base 6. The rim shoulders serve for the radial support of the tire and the rim flanges for the axial support of the tire. The disc part 3, shown here only partially, is provided with bolt holes for mounting the vehicle wheel 1 to the hub on the hub connection surface and furthermore, in the transition part, is provided with ventilation holes (not shown) for cooling the brakes. The vehicle wheels can have different geometries and designs, which is why the vehicle wheels shown are only of a symbolic nature and do not limit the invention thereto.

[0033] In the exemplary embodiment according to Fig. 1, a tire pressure valve 8 of a tire pressure monitoring system (RDKS), not further shown, is also shown in a schematic manner. The tire pressure valve 8 is provided with at least one internal tire pressure sensor, an energy source for providing energy and a transceiver for transmitting a measurement signal from the internal tire pressure sensor to a tire pressure control device of the vehicle, in order to display the current internal tire pressure of each tire to the driver, as currently prescribed for new vehicles. Vehicle wheels with any structure and equipped with a tire pressure valve for a tire pressure control system are known to the person skilled in the art, which is why they will not be further described here.

[0034] A measuring device 10, which is further arranged radially outside the rim part 3 of the vehicle wheel, is essential for the invention. In FIG. 1, the measuring device 10 is arranged in the transition of the rim well base 6 between the well base bottom 7 and one of the rim shoulders 5. The measuring device 10 consists of a metal strip 11, which is glued to the outer periphery of the rim part 3 by an adhesive connection. Here, the metal strip 11 is then provided in the middle of its longitudinal and transverse extent with a measuring sensor 12, as can be clearly seen in FIG. 2 and FIG. 3, which is provided here with a total of four strain gauges 13, 14, as the schematic diagram in FIG. 2 approximately shows. Two strain gauges 13 are oriented in the circumferential direction, i.e. in the direction of rotation of the vehicle wheel rotating around the wheel axis, and two strain gauges 14 are oriented transversely to the circumferential direction. The individual strain gauges 13, 14 are connected like a Wheatstone measuring bridge in order to provide the deformation of the metal strip as a sensor measurement signal. The measuring sensor 12 measures the deformation of the metal strip 11, which corresponds to the deformation of the vehicle wheel 1 in the area of ​​the rim portion 3. The extent and direction of the deformation depends on the weight of the vehicle together with the respective load and, in the case of a moving vehicle, also on the dynamic load. Furthermore, there is the influence of the mounted tire as well as the influence of the internal pressure and temperature of the tire.

[0035] As can be clearly seen in Figures 1 to 3, the metal strip 11 has a length that is much larger and a width that is somewhat larger than the size of the measurement sensor 12. The entire metal strip including the measurement sensor 12 is covered by a plastic cover 15 on the periphery of the measuring device 12. The entire underside 17 of the metal strip 11 and the underside 19 of the plastic cover extending beyond it are fixed to the surface of the rim component 3 by means of an adhesive layer 16, which is shown diagrammatically in Figure 3. In the exemplary embodiment shown, the adhesive layer 16 has a thickness D K is the thickness D of the metal strip 11 S 2 and 3, the metal strip 11 has a thickness of 1 mm, which is slightly smaller than the thickness of the upper side 18 of the metal strip 11. This is merely for the sake of example, and in the description and claims, different thickness ratios as well as different materials and material properties of the metal strip and adhesive for the adhesive connection are addressed. In the mounted state, the measuring sensor 12 fastened to the upper side 18 of the metal strip 11 is completely protected between the plastic cover 15 and the metal strip 11. Due to the position of the measuring device 10 in the tire outside the rim part 3, this measuring device 10 is also largely protected against external influences. By arranging the measuring device close to the tire pressure valve 8 of the tire pressure control device, the energy source and the transceiver of the tire pressure valve can be used to supply energy to the measuring sensor 12 of the measuring device 10 and furthermore the measuring signal of the measuring sensor 12 can be wirelessly transmitted to the vehicle-side evaluation device of the vehicle-side monitoring device (not shown). In Figs. 2 and 3, the metal strip 11 has a constant thickness D between the upper side 18 and the lower side 17 along its entire length in the circumferential direction. S However, it may well be the case that it is only present with a constant thickness only in the area in which the measurement sensor or sensors are arranged.

[0036] Figure 4 shows a slight modification of the measuring device according to Figure 2. The main difference is that the measuring device 110 according to Figure 4 is provided with two measuring sensors 112A, 112B, which are arranged offset from one another in the circumferential direction on the metal strip 111 of the measuring device 110. Here too, the entire metal strip 11 together with the two measuring sensors 112A, 112B is entirely covered by a plastic cover 115, and fastening to the vehicle wheel is performed by adhesive connection on the underside of the plastic cover 115 and on the underside of the metal strip 111, respectively, as in the previous exemplary embodiment. When the measuring device 110 is provided with two measuring sensors 112A, 112B, which are arranged offset from one another in the circumferential direction, the distance between the two measuring sensors 112A and 112B can be selected such that in the mounted state the angular distance between the two measuring sensors 112A and 112B is at least 20° in the circumferential direction, preferably even at least 22.5°. The overall length of the metal strip 111 within the measuring device 110 must be correspondingly long enough.

[0037] Figures 5-7 show yet another alternative embodiment. As in the previous exemplary embodiment, the measurement is performed indirectly via a metal strip 211, which is fastened by means of a not shown adhesive connection to the outside of the rim part 203 of the vehicle wheel and in this respect perfectly senses and transmits the deformations of the rim part. A measuring device 210 provided with a housing 218 is fastened to the metal strip 211, i.e. to two anchor nuts 219 spaced apart from each other in the circumferential direction, as can be clearly seen in Figure 6. Here, the measuring device 210 has a bending strut 220, the two ends of which are respectively fixed on the anchor nuts 219, circumferentially offset from each other, by means of removable fastening screws 221. A strain gauge (not shown) is then fastened to the bending strut 220. A power supply and a transceiver can also be arranged in the housing 218 so that the measuring sensor 210 can be replaced by another measuring sensor if necessary. The anchor nuts can be made of the same material as the metal strip 211 and can be welded or brazed to the metal strip 211, but they can also be produced in other ways, for example fastened to the metal strip 211 by adhesive connection. The metal strip 211 can be provided with one or, as here, several recesses 222 between the two anchor nuts 219, the recesses 222 being preferably positioned symmetrically with respect to and between the two anchor nuts 219.

[0038] Here too, the metal strip 211 extends circumferentially beyond the anchor nut 219. The anchor nut 219 extends transversely to the circumferential direction by a first larger width B 1 The metal strip 211 has a region having a width B 2 is preferably the width B of the subsection 211A. 1The subsection 211B may extend over the remaining periphery of the rim component 203 (FIG. 5), such that the metal strip 211 is disposed all around.

[0039] FIG. 8 serves as an illustration of the rotation angle α between the position of the wheel contact area A, where the total wheel load L is supported on the ground, and the actual current position P of the sensor arrangement of the measurement sensor of the measuring device, which rotates with the vehicle wheel. At each position or each rotation angle α of the position P of the measurement sensor relative to the contact area A, the deformation of the rim part can be measured by means of a strain gauge and returned as a measurement signal to the evaluation device. Thereby, the measurement signal follows a periodic path that depends on the angle α (or over time t, in the case of a moving vehicle), as shown in FIG. 9. FIG. 9 again shows the load-dependent part g(P)*L*c(α) and the non-load-dependent element e, which has been explained above. 0 and θ = θ ...

[0040] Figures 10 to 13 show a third further different embodiment. The vehicle wheel is generally indicated by the reference number 301, the wheel having a disk part 302 and a rim part 303, as known per se. The rim part 303 also has two rim flanges 304, two rim shoulders 305 and a multi-stage rim well base 306, as known per se. The disk part 303, which is only partially shown here, is provided with bolt holes 340 and vents 341, which may have different positions and configurations, as known per se to the person skilled in the art. A measuring device arrangement 350, which also comprises two measuring devices 310 of the same construction, is further arranged radially outside the rim part 303 of the vehicle wheel. The measuring device arrangement 350 with the two independent measuring devices 310 is arranged in the transition of the rim well base 306 between the well base bottom 307 and one of the rim shoulders 305. The measuring device array 350 consists of two measuring devices 310, both of the same configuration and structure, as shown in detail and schematic form in Figures 11 and 12. Each of the measuring devices 310 is arranged symmetrically in the valve hole 308 and comprises a valve, as well as a tire pressure monitoring system (RDKS) referenced 360. The tire pressure monitoring system 360 comprises several elements, including a housing, as well as a battery and electronic circuitry (not shown) within the housing, which is here also used for detection, monitoring and transmission of the sensor signals of each of the measuring devices 310 to a monitoring device of the vehicle, on which the wheels are mounted.

[0041] The construction principle of each of the measuring devices 310 can best be seen from figures 12 and 13. Each of the measuring devices 310 comprises, on both circumferential opposite ends, an outer first section built by a metal band strip 371 and a second section built by a metal plate strip 372. The metal band strip 371 and the metal plate strip 372 are fixed to each other, preferably by welding or soldering. The underside of the metal band strip 371 is fixed to the outside of the rim by a glue layer referenced 381 in figure 13. The same glue layer is also used to fix the circumferentially outer part of the metal plate strip 372 to the outside of the rim. The metal plate strip 372 is thicker than the metal band strip 371 and also has a longer extension in the circumferential direction, while the widths of the metal plate strip 372 and the metal band strip 371 are identical. In figure 13, the dashed line 385 indicates the line where the metal plate strip 372 starts and the metal band strip 371 ends. The metal sheet strip 372 comprises on its bottom surface a thickness reduction step 375, and the adhesive layer 381 extends over almost the entire extension length of the metal band strip 371, but only close to the thickness reduction step 375 on the bottom surface of the metal sheet strip 372. Due to the thickness reduction step 375, a gap exists between the periphery inside of the metal sheet strip 372 and the outside of the rim. Finally, the bending strut 320 is fixed between the inner ends of the metal sheet strips 372 facing each other. The bending strut 320 is formed by a central metal band strip 377 and has a smaller thickness and also a smaller width compared to the metal sheet strip 372.

[0042] The measurement sensor 312 preferably has a very similar configuration as the measurement sensor shown in FIG. 2 and described in connection with that embodiment, so that it has a total of four strain gauges, of which two strain gauges 313 are oriented in the circumferential direction, i.e. in the direction of rotation of the vehicle wheel rotating around the wheel axis, and two strain gauges 314 are oriented transversely to the circumferential direction. The individual strain gauges 313, 314 are connected like a Wheatstone measurement bridge to form the bending strut 320 and provide the deformation of the metal band strip 377 used as bending strut 320. The measurement sensor 312 measures the deformation of the central metal band strip 377 or the bending strut 320, respectively, between those sections of the metal band strip 371 and the metal tape strip 372, which is fixed to the rim by an adhesive connection, so that both the circumferential deformation and the transverse deformation are detected. To detect both the axial and circumferential deformations, it is sufficient to arrange the measurement sensor 312 on the bottom surface of the central metal band strip 377.

[0043] In a preferred embodiment, as shown in figures 10 and 11, the two measuring devices 310 are installed symmetrically with respect to the valve hole and the tire pressure monitoring system, which is placed on the valve inserted in the valve hole. The entire electronics of the tire pressure monitoring system, including the battery, can be used by connecting the measuring sensor 312 to the electronics, preferably by wiring. No additional connections between the individual measuring devices and the tire pressure monitoring system and its electronics are necessary. The length and position of each of the measuring devices are preferably configured such that the two centers of each of the central metal band strips are arranged with an offset of 40°. The center of each of the central metal band strips 377 corresponds to the center position of each of the measuring sensors 312. The fixing of each of the metal band strips of the measuring devices by gluing to the outside of the rim is easy to perform and the same sensor can be used with any type of wheel and wheel size. The two measuring sensors of the measuring device arrangement 350 make it easy to avoid the risk of zero crossing. It is also possible to measure the wheel load even in stationary state, when the vehicle is not aware.

[0044] The measuring device does not have to be fixed to the wheel rim at the location of the valve hole, but may be used at different locations depending on the most deforming zone. The greater the deformation, the better the load estimation error of the measuring arrangement with the measuring device. By adding an additional gyroscope sensor, an indirect vehicle speed measurement may also be realized.

[0045] Numerous variations will become apparent to those skilled in the art from the foregoing description, which are intended to be included within the scope of the appended claims.

Claims

Claim 1 A vehicle wheel, comprising a rim part (203) having a rim flange, a rim shoulder, and a rim well base for supporting a tire, a hub connection flange having bolt holes and a transition part having a vent, a disk part connected to the rim part for non-rotatably fastening the vehicle wheel to the vehicle, at least one measuring sensor for detecting a force acting on the vehicle wheel, and a transceiver coupled to the measuring sensor for transmitting load data detected by the measuring sensor to a component outside the vehicle wheel, and a measuring device (110) rotatably fastened to the vehicle wheel, - A metal strip (111) is attached to the radially outer side of the rim part (203), and the at least one measuring sensor (112) is assigned to the metal strip, - The metal strip has a lower side and an upper side and at least one partial section having a constant thickness in the circumferential direction between the lower side and the upper side, - The lower side of the metal strip is connected to the outer side of the rim part along the partial section by an adhesive connection, - The measuring device (110) has a bending strut (220) provided with the at least one measuring sensor, and the strut is connected to the metal strip in two fastening zones spaced apart from each other in the circumferential direction of the rim part for local detection of deformation of the metal strip between the fastening zones, and - The metal strip (211) has a circumferential length of the vehicle wheel greater than the distance between the fastening zones from each other A vehicle wheel, characterized in that. Claim 2 The vehicle wheel according to claim 1, characterized in that the fastening zones consist of two anchor pins or anchor nuts (219) offset from each other in the circumferential direction and fastened to the upper side of the metal strip. Claim 3 The vehicle wheel according to claim 1, characterized in that a recess (222) between the fastening zones is partially provided in the metal strip (211), and the recess is symmetrically attached to the fastening zones. Claim 4 The metal strip extends only partially on the periphery of the rim portion, or the metal strip extends completely on the periphery of the rim portion, and the metal strip has strip widths (B １ , B ２ ) that are different in the lateral direction with respect to the circumferential direction, and has at least two partial sections (211A, 211B), the vehicle wheel according to claim 1. Claim 5 The measuring device (210) is provided with a housing (218), and an electric circuit arranged in the housing together with the transceiver, the bending strut (219), and the measuring sensor, and the measuring device is fastened to the fastening zone as a unit in a separable and replaceable manner. The vehicle wheel according to claim 1.

6. The metal strip (311) of one measuring device (310) comprises several sections, a thin metal strip constructs the outer surrounding section, and a thicker metal plate strip constructs the inner surrounding section, and the bending strut is composed of a central metal strip fixed between the inner ends of the metal plate strips facing each other. The vehicle wheel according to claim 1.

7. Two measuring devices each having a measuring sensor on its bending strut are positioned offset from each other in the circumferential direction. The vehicle wheel according to claim 6.

8. The measuring sensor (12, 112, 312) is designed as a measuring surface having four strain gauges (13, 14, 313, 314), of which two strain gauges (13) are oriented in the circumferential direction and two further strain gauges (14) are oriented transversely to the circumferential direction, or the measuring sensor is connected by an electronic circuit, the transceiver, and a cable connection to a power supply, and they form components or additional parts of a tire pressure measuring device (TPMS) assigned to the vehicle valve. The vehicle wheel according to claim 1.

9. At least two measuring sensors (112A, 112B) dispersed on the periphery of the rim part are positioned offset from each other in the circumferential direction, and the distance between the two measuring sensors relative to each other in the circumferential direction is preferably at least 20°. The vehicle wheel according to claim 1.

10. A monitoring device for a vehicle having several vehicle wheels, said monitoring device comprising at least one vehicle wheel according to claim 1, provided with a metal strip (11; 111), whereby a measuring device (10) having a measuring sensor (12) and a transceiver coupled to said measuring sensor are associated, having a vehicle-side evaluation device for said measuring signal of said measuring sensor, characterized in that said monitoring device is designed and formed such that the dynamic load in the driving operation and the static load in the stationary state of the vehicle on said associated vehicle wheel can be determined from said measuring signal of said measuring sensor, and in order to determine the dynamic load by said evaluation device, a measuring signal amplitude between the measured maximum signal value and the measured minimum signal value in one rotation of the wheel is determined and compared with an amplitude value from a vehicle wheel calibration reference curve for determining a deviation factor, and in order to determine the static load, the rotation angle between said sensor position and said wheel contact position is determined, and the measured signal value is compared by said evaluation device with a reference value from a vehicle wheel calibration reference curve for the same rotation angle, and several vehicle wheel calibration reference curves for different temperatures and internal tire pressures are stored in said evaluation device.

Images