Vehicle wheel equipped with a monitoring device and monitoring device for a vehicle wheel

Abstract

The present invention relates to a vehicle wheel with a monitoring device, the monitoring device 10 comprising a housing 11 rotatably arranged on the rim portion 2 of the vehicle wheel, and an electronic circuit 20 arranged in the housing 11 and coupled to a load detection device having strain gauges arranged in the housing for detecting forces acting on the vehicle wheel. In order to create a monitoring device that is easy to install on different vehicle wheels and can reliably determine the load forces occurring on the vehicle wheel, the housing 11 has two fastening zones 12, 13 arranged at a distance from each other and connected to each other via at least one bending strut connected to both fastening zones as components of the load detection device, and at least one pair of strain gauges is arranged on the bending strut between the fastening zones for detecting bending of the bending strut caused by the load force.

Description

[Technical Field]

[0001] The present invention relates to a vehicle wheel having a monitoring device, the monitoring device comprising: a housing rotatably disposed on a rim portion of the vehicle wheel; an electronic circuit disposed within the housing and coupled to a load sensing device having strain gauges for sensing forces acting on the vehicle wheel; and a transceiver coupled to the electronic circuit for transmitting load data sensed by the load sensing device to components outside the vehicle wheel. [Background technology]

[0002] In particular, heavy goods vehicles and conventional heavy goods transport vehicles are subject to weight restrictions on certain routes. To determine the load capacity within a vehicle, weight sensors may be permanently installed on the vehicle's fixed frame between the vehicle chassis and the vehicle's load area. These corresponding load sensors are intended to record the weight on the truck's load area only. These sensors do not provide other data about other vehicle conditions and are not designed to detect other conditions, such as mass distribution, temperature, tire pressure, wheel camber, etc. Such load conditions and other recorded operating conditions may affect how vehicle systems react during operation.

[0003] Patent Document 1 discloses a monitoring device with a load sensing device mounted on the outer periphery of the rim of a vehicle wheel so that the sensor is protected from environmental influences inside the tire. The load sensing device has strain gauges designed to determine impact loads acting on the vehicle wheel under both static and dynamic conditions by determining the force generated by the rotation of the vehicle wheel as a sinusoidal signal and determining the wheel load from the maximum recorded value. If necessary, static loads, including the rotational position of the monitoring device relative to the vehicle contact area, can also be recorded and the load can be determined by correlating the strain gauge measurement signal with previously recorded measurement data under different loads. In the known solution, the monitoring device's housing is fixed to the rim bottom, preferably by adhesive bonding, and has a base that curves according to the curvature of the bottom. The electronic circuitry is preferably divided into two circuit boards, and the strain gauge is located on the flat upper side of the lower part of the case. A cover is provided to protect all electronic components inside the housing. Additional sensors, preferably split between two circuit boards, are located within the housing to record various vehicle conditions, such as wheel clamping force, wheel load, axle load, mass distribution, ambient temperature, wheel temperature, and tire pressure. Information obtained from the sensors can be used by different systems, including, but not limited to, a traction control system (TCS), anti-lock braking system (ABS), electronic brake force distribution (EBD), anti-roll stabilizer (AAR), collision prevention braking system (CMBS), collision mitigation braking (CMB), all-wheel drive (AWD), tire pressure control system (RDKS, TPMS), and tire wear and damage control reporting. To permanently power the monitoring device, a piezoelectric element and energy-generating circuitry are provided within the housing to convert energy generated by the vibration of the piezoelectric element into electrical energy and store the electrical energy. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] German Patent No. 11 2016 004 151 T 5 Specification Summary of the Invention [Problem to be solved by the invention]

[0005] The object of the present invention is to create a vehicle wheel and a monitoring device for the wheel that is easy to install, can be used with different wheels, and can reliably determine the load forces occurring on the wheel due to the vehicle weight, driving maneuvers, and load with little measurement effort. [Means for solving the problem]

[0006] To solve this problem, the present invention proposes that the housing of the monitoring device has two fastening zones spaced apart from each other in the circumferential direction of the rim portion, and that these fastening zones are connected to each other as part of the load sensing device by at least one bending strut connected to both fastening zones, and that at least one pair of strain gauges is arranged on the bending strut between the fastening zones to sense deformations of the bending strut caused by any kind of force acting on the wheel, which force is generally called load force (or strain force).

[0007] In the present invention, the load force applied to each wheel of a vehicle due to the vehicle's weight, driving operation, and load is indirectly determined by the deformation of a preferably metallic portion of the rim caused by the load force between two fixed zones of a monitoring device having a fixed predetermined distance. At least one bending strut, to which at least one pair of strain gauges is assigned, is located between the fastening zones. Data determined by the deformation of the rim at the bending strut due to the deformation of the rim by the strain gauge is used to determine the load force. Deformation of the rim portion between the spaced-apart fastening zones causes a corresponding deformation of the bending strut between the fastening zones, which can be detected by the strain gauge. The detected deformation can be bending in some cases, but can also be torsion, internal pressure, or tension of the deformed bending strut, or any combination thereof.

[0008] According to a particularly advantageous design, a one-piece adapter plate or a multi-piece adapter device, the underside of which is adapted to the curvature of the rim section, is fastened, particularly glued, to the radially outer surface of the rim section. In a particularly advantageous design, a monitoring device housing having spaced-apart fastening zones is fastened by a detachable screw or pin connection to a cover surface of the adapter plate, which is formed away from the base surface of the adapter plate. By interposing the one-piece adapter plate or the multi-piece adapter device between the monitoring device housing and the surface of the rim section, identical monitoring devices, preferably having a flat underside or housing underside, can be fixed to rim sections with different curvatures. At the same time, a pin or threaded connection can be provided between the adapter plate and the monitoring device housing, allowing for easy replacement of the monitoring device without the need to change the wheel rim manufacturing process already in use. It is particularly advantageous if the adapter plate, which may be one-piece, is provided with threaded holes for the threaded connection that are offset from each other in the circumferential direction of the rim section. In a multi-piece adapter device, each adapter element can have a threaded hole, and the adapter elements can be arranged so that the threaded holes are properly spaced. The monitoring device housing can then be relatively easily fastened to the adapter plate or adapter device by cap screws, which pass through the fastening zone through-holes and reach the fastening zone, thereby forming a defined fastening zone during which deformation of the rim portion is determined by bending struts and strain gauges.

[0009] According to an advantageous design, the adapter plate is flat on the cover surface and / or has recesses or indentations to reduce weight. The adapter plate can also have a curved upper surface, and the housing of the monitoring device is then adapted to the shape of the upper surface of the adapter plate. The recesses or indentations in the adapter plate can reduce the additional weight introduced by the adapter plate to the vehicle wheel. If several adapter elements are used, these can be designed to be correspondingly small.

[0010] According to an alternative design, the radially outer surface of the rim portion can have circumferentially spaced tapped holes or anchor pins to which the monitoring device housing can be attached or attached by spaced-apart fastening zones. Also, circumferentially spaced anchor nuts can be fixed to the radially outer surface of the rim portion, thereby facilitating fastening of the monitoring device to the rim portion. Preferably, a pair of tapped holes, anchor pins, or anchor nuts is arranged on a circumferential line perpendicular to the wheel axis. Fixing of the anchor pins or nuts can be achieved by welding, adhesive bonding, or any other suitable joining technique. The tapped holes, anchor pins, or anchor nuts should be fixed and formed so that the hole axis or pin axis is again perpendicular to the wheel axis.

[0011] A novel monitoring device for a vehicle wheel comprising: a housing that can be rotatably mounted on the deep bottom of the rim portion of the wheel; an electronic circuit disposed within the housing and coupled to a load detection device having strain gauges for detecting forces acting on the vehicle wheel; and a transceiver coupled to the electronic circuit for transmitting load data detected by the load detection device to a component external to the vehicle wheel, wherein the load data is transmitted to the component external to the vehicle wheel; the housing has two fastening zones spaced apart from each other and connected to each other via at least one bending strut connected to both fastening zones as a component of the load sensing device; and at least one pair of strain gauges is disposed on the bending strut between the fastening zones for detecting deformation of the bending strut caused by the load force.

[0012] The ease of installation of the monitoring device is particularly advantageous if each fastening zone has at least one through-hole for a pin or screw connection. In principle, each fastening zone can have several through-holes, preferably arranged symmetrically with respect to the bending support. It is particularly advantageous if each fastening zone has exactly one through-hole for a pin or screw connection, and two through-holes are arranged symmetrically with respect to the bending support or bending supports and are arranged on the wheel in an assembled state on a common circumferential line perpendicular to the wheel axis of the vehicle wheel.

[0013] The housing advantageously has a cavity covered by the housing wall for enclosing the electronic circuit, and at least one bending strut is arranged within or bounds the cavity. Depending on the design, a single bending strut may be arranged between the fixing zones and / or between the centers of the fixing holes, and may be arranged symmetrically with respect to an imaginary bond line between the fixing holes or their centers, and the bending strut is preferably associated with only one pair of strain gauges.

[0014] According to an alternative design, the bending strut can be partially two-armed between the fastening zones and / or between the centers of the fastening holes, whereby preferably only one strain gauge is assigned to each arm of the bending strut.

[0015] In both of the above designs, the flexible strut / flexible strut can be detachably coupled to the fastening zone, in particular via a cylindrically enlarged head at the end of the strut, which head is inserted transversely to the extension direction of the flexible strut into a suitably designed cylindrical receptacle in the fastening zone and fixed there, in particular by a press fit or intermediate fit.

[0016] In order to increase the flexibility of the bending support and thus the signal detectable by the strain gauges via the notches and notched geometry, it is also particularly advantageous if the strain gauges are arranged adjacent to a bending hinge integrally formed in the bending support or in a portion of the bending support opposite an integrally formed bending hinge, for example a notched bending hinge. By providing or allocating a flexible hinge or a flexible mechanism with a bending hinge to the bending support, the measurement accuracy of the monitoring device is significantly improved.

[0017] According to an alternative advantageous design, the bending struts can be formed as a pair of cross struts adjacent to one of the fastening zones, each cross strut extending perpendicular to the displacement direction between the two fastening zones, and preferably each cross strut is associated with a strain gauge of a pair of strain gauges. Preferably, in this configuration, bending hinges integrally formed in the housing are provided between the transverse struts and the fastening zones, and preferably the strain gauges are fastened to the relevant bending struts in each case near the relevant bending hinge. Again, the flexibility provided by the flexible or bending hinges significantly improves the precision and measurement accuracy of the monitoring device, which detects the circumferential deformation of the rim portion as a measure of the load force, because the flexible hinge amplifies the deformation and therefore the signal output.

[0018] It is particularly advantageous when a pair of cross supports is used in a design where the fastening zones located adjacent to the pair of cross supports have a single through-hole and the ends of the cross supports of the pair are connected to the other fastening zones via the wall web.It is particularly advantageous when the fastening zones adjacent to the pair of cross supports are designed as symmetrically tapered mounting seats with a bending hinge.In this design, a bending hinge can be arranged in the connection area between the fixing seat and the corresponding cross support of the pair of cross supports.

[0019] The fixing seats can only be integrated into the cross struts via narrow webs further tapered by bending hinges. It is also possible for connecting walls to be formed between the fixing seats and the outer ends of the transverse struts, the connecting walls preferably having a wall thickness at least 30% less than the maximum wall thickness of the transverse struts and / or the connecting walls being provided with at least one fold or radius, so that despite their presence their influence on the deformations detectable on the transverse struts by the strain gauges is reduced.

[0020] According to another embodiment of the monitoring device, the bending support can comprise, or consist of, a rectangular bending frame having a transverse coupling arm and a longitudinal bending arm, the transverse coupling arm extending perpendicular to the direction of the offset between the two fastening zones. Preferably, the strain gauges are arranged in pairs, with each strain gauge of the pair assigned to or fixed to each of the longitudinal bending arms. The strain gauges can be arranged only on the inner or outer surfaces of the longitudinal bending arms, or preferably, there are two pairs of strain gauges, with one strain gauge of each pair arranged on the inner side of the longitudinal bending arm and one strain gauge of each pair arranged on the outer side of the longitudinal bending arm.

[0021] It is particularly advantageous if the bending column with a rectangular bending frame is detachably coupled to the fastening zone, which can be achieved via a coupling part that is fixed at one end to the transverse coupling arm and at the other end comprises a pin head part that can be inserted into a receptacle of the corresponding fastening zone facing the bending column.

[0022] According to a preferred embodiment, each linkage is triangularly formed having a triangular base and a triangular tip, with a pin head portion formed in the triangular base and the triangular tip being connected to a linkage arm, and preferably a flexure hinge integrally formed in the linkage arm adjacent the triangular tip.

[0023] The detachable connection can be achieved by self-centering, preferably by a three-point connection between the head portion of the strut end and the receptacle of the fastening zone, preferably with the bending frame, pin head portion, receptacle and connecting portion arranged symmetrically with respect to a circumferential line again extending perpendicular to the wheel axis.

[0024] In order to have good interference between the detachable bending posts and the receptacles of the fastening zone, it is preferred that the pin head portions have an outer radius or curvature that is slightly larger than the inner radius or curvature of the receptacles, or that the distance between the centers of the pin head portions is larger than the distance between the centers of the receptacles.

[0025] Also, according to an advantageous embodiment, the housing of the monitoring device can have at least two, preferably three, sections constituting a main section with fastening zones and at least one side section, the bending struts being arranged in the main section and the electronic circuit and / or energy cell being arranged in at least one side section. The housing can be fixed to the rim section so that the main section with the bending struts extends between the fastening zones, while the side sections are arranged offset in the circumferential direction of the fastening zones. The multiple sections make the housing longer but thinner, reducing impact with the tire during tire installation.

[0026] As is already known from the state of the art, in addition to the load sensing device, the monitoring device may have an accelerometer sensor and / or a temperature sensor and / or an angle sensor and / or a pressure sensor for obtaining further operating data, and / or the monitoring device may be equipped with a rechargeable energy cell and a piezoelectric element for generating energy so that the energy cell can operate continuously. However, the monitoring device may also be equipped with a battery with a limited service life, since this can be easily replaced, in particular by means of a screw or pin connection.

[0027] Further advantages and designs of the invention arise from the following description of an example, which is shown diagrammatically in the drawings, for the construction of a monitoring device according to the invention. [Brief explanation of the drawings]

[0028] [Figure 1] 1 is a not-to-scale plan view of a vehicle wheel showing, in a simplified schematic form, a portion of the rim on which a monitoring device is mounted; [Figure 2] FIG. 1 is a perspective view of a monitoring device attached to a rim portion that is only partially shown. [Figure 3] 3 is a longitudinal section through a monitoring device mounted on the rim portion according to FIG. 2; [Figure 4] 3 is a plan view showing, in a simplified schematic form, the structural internal structure of the monitoring device according to FIG. 2; FIG. [Figure 5] 5 is a simplified schematic diagram of the structural internals of a monitoring device similar to the design example shown in FIG. 4, but in an alternative form. [Figure 6] 10A and 10B show a simplified schematic diagram of the structural internal design of a monitoring device according to an alternative design example having straight bending struts extending between fastening zones. [Figure 7] 7 is a longitudinal section through a monitoring device mounted on a rim portion according to FIG. 6; [Figure 8] 10 shows a simplified schematic diagram of the structural internal design of a monitoring device according to another alternative design example having a partial two-armed bent strut extending between the fastening zones. FIG. [Figure 9] FIG. 10 is a perspective view (partially shown) of an alternative embodiment monitoring device attached to a rim portion. [Figure 10] 10 is a longitudinal section through a monitoring device mounted on a rim portion according to FIG. 9; [Figure 11] FIG. 11 shows a schematic simplified structural internal design of the load support of the monitoring device according to FIGS. 9 and 10. DETAILED DESCRIPTION OF THE INVENTION

[0029] In FIG. 1, a vehicle wheel for a passenger car or commercial vehicle is generally designated by the reference number 1 and has a rim portion 2, which may be of any structure or design type and is connected or formed with a not-shown bowl portion, by which the vehicle wheel 1 with the key portion and rim portion can be connected to the vehicle hub. The vehicle wheel can consist of a separately manufactured rim and bowl portion, but can also consist of a single cast part. The rim portion 2 has two rim shoulders 3, 4 for supporting a tire, not shown, between which is a rim base 5 with two base sides 6, 7. The visible surface of the rim portion 2 in FIG. 1 forms its outer periphery or side, which is symmetrical about the wheel axis. In the illustrated design example, in the area of ​​the outer periphery of the rim base 5, a monitoring device, generally designated by the reference number 10, is attached in two fastening zones spaced apart from each other around the periphery of the base, so that the monitoring device extends circumferentially along its longer axis. Mounting the monitoring device 10 on the underside of the rim underside 5, particularly near the outer underside 6, i.e., opposite the wheel hub, provides a preferred mounting location for the monitoring device 10. However, the monitoring device 10 can also be mounted in other areas of the rim portion 2. When the tire is mounted, the monitoring device 10 is located within the pressure-loaded interior of the tire.

[0030] 2 and 3 show a perspective view and a cross-sectional view of the monitoring device 10 according to the first embodiment. As can be seen, the monitoring device 10 has a housing 11 that is only indirectly, not directly, connected to the rim base 5, since the housing 11 is fixed to an adapter plate 30, which itself is fixed, particularly glued, to the surface of the rim base 5. The adapter plate 30 has a base side 31 that precisely matches the curvature of the rim base 5 and therefore lies flat relative to the rim base 5. The adapter plate 30 has a flat cover surface 32 in the illustrated design, so that the housing 11 of the monitoring device 10 itself has a flat underside 12. The advantage of using an adapter plate 30 is that it is possible to adapt to different radii of curvature of the rim section by using different adapter plates, so that the same or each identical monitoring device can be used for other vehicle wheels with different dimensions.

[0031] The attachment between the housing 11 of the monitoring device 10 and the underlying adapter plate 10 is not flat, but only on two fastening zones 12, 13 which are in circumferential contact with one another, which in the illustrated exemplary design are in each case represented by a cap screw 15 for each fastening zone 12, 13, through which the housing 11 of the monitoring device 10 is screwed into the adapter plate 30. The adapter plate 30 therefore has a threaded hole 33 for each of the two cap screws 15, whereby the distance between the two threaded holes 33 is adapted to the distance between one through-hole 16 of one fastening zone 12 and the other through-hole 17 of the other fastening zone 13.

[0032] In the example shown, a sleeve 18 is inserted into each of the two through holes 16, 17 and is passed through by the shank of a cap screw 15. The adapter plate 30, and therefore also the monitoring device 10, is positioned on the rim bottom so that the two screw holes 33 are parallel to the circumferential direction and are therefore aligned with a circumferential line perpendicular to the wheel axis.

[0033] Forces introduced into the rim section as a result of external fluctuations, particularly the vehicle weight and vehicle load, result in deformations of the rim section in the circumferential direction, with the wheel contact surface area reaching a maximum value. The monitoring device 10 with its load detection device is designed to detect these deformations in order to determine the load forces actually acting on each vehicle wheel using a sensor system, as described below. During vehicle movement, the monitoring device 10, which rotates with the vehicle wheels in a constant motion, reaches a position opposite the wheel contact surface with each rotation, where it can detect the maximum deformation value with each rotation. If only one screw connection is used in each fastening zone 12, 13 to fasten the fastening zone 12, 13 to the lower adapter plate, and both screw connections are in contact with each other in the direction of rotation of the vehicle wheel, deformations can be detected using an appropriate sensor system essentially without lateral forces. For this reason, it is not necessary for the adapter plate 30 to lie flat against the rim bottom 5, since it is still sufficient to detect deformations if the adapter plates are offset from one another in the circumferential direction or downwards and are in contact with the outer surface of the rim part only in the areas of the two fastening zones adjacent to the screw holes. A recess or depression can be provided in the middle area of ​​the adapter plate, which is advantageous in minimizing the additional weight caused by the adapter plate. Alternatively, instead of a one-piece adapter plate, an adapter device with several adapter elements is used.

[0034] 3 above a printed circuit board is arranged inside the housing 11 of the monitoring device 10, in order to detect deformations of the rim portion caused by the weight and load forces and transmit them to external components such as the vehicle electronics or an on-board computer. This electronic circuit is coupled to a load detection device coupled to at least one pair of strain gauges 21 and to a transceiver (not shown in detail) via which the load data detected by the load detection device can be transmitted contactlessly, for example wirelessly, to corresponding components outside the wheel. The electronic circuit 20 is powered by a battery 23 arranged inside the housing 11, sealed against external influences. The electronic circuit 20 may have further sensors, such as pressure sensors 24, acceleration sensors, temperature sensors (not shown), angle sensors, etc., to determine further operational data of the associated vehicle wheel and to determine the position of the monitoring device relative to the wheel contact surface.

[0035] In the inventive monitoring device 10, the load detection device detects deformations occurring in the housing 11 between the two fastening zones 12 and 13, which in the illustrated design are between the two axes of the respective cap screws 15 or the axes of the associated through-holes 16, 17. The greater the distance between the two fastening zones 12 and 13, the better the detection of circumferential wheel rim deformations. Thus, in the illustrated design, both fastening zones 12 and 13 are located at opposite ends of the housing 11, and the entire electronics, along with any additional sensors and circuit boards for the electronic circuit 20, are located between the two fastening zones 12 and 13. However, it is also possible to position the fastening zones 12 and 13 at a smaller distance from each other and to place the electronics and receiver completely or partially in an area not between the two fastening zones 12 and 13.

[0036] The load sensing device can be installed and positioned in different ways between the two fastening zones. FIG. 4 schematically illustrates the basic principle of the load sensing device in the monitoring device 10 shown in FIGS. 2 and 3. As can be clearly seen from the top view of the housing 11, the two fastening zones where the offset through-holes are located are respectively designed as different mounting seats 40, 41. The mounting seat 40 is positioned near two of the pair of strain gauges 21, while the mounting seat 41 is positioned away from the strain gauges 21. Between the two fixing seats 40, 41, the housing 11 has two outer web-like side walls 42 that extend parallel to each other and, when the monitoring device 10 is installed, extend over the vehicle wheel in a circumferential direction parallel to the vehicle wheel. The mounting seat 41 is integrally connected to the right end of the side wall 42 in FIG. 4 via several webs 43, 44, thereby providing a relatively rigid connection to the side wall 42. The mounting seat 40, on the other hand, tapers sharply in the direction of the connecting bridge 46, which extends perpendicularly to the side wall 42. The fixing seat 40, which forms the fixing area 12, is therefore connected to the fixing seat 41, which forms the other fixing area 13, via the connecting web 46, the side wall 42, and the webs 43, 44. With respect to the mounting seat 40, the connecting web 46 forms two cross struts 47A, 47B of the cross strut pair, each of which is associated with a strain gauge 21. Each of the two cross struts 47A, 47B forms a bending strut in the monitoring device 10, on which deformations of the housing between the two fastening zones 12, 13 or between the mounting seats 40, 41 forming them are applied in order to detect the deformations and thus the sensor signals for the load forces via the strain gauges 21. The deformation capacity of the two cross struts 47A, 47B forming each bending strut of the load sensing device is determined by placing one bending hinge 48A, 48B respectively between the foot region 49 of the fixing base 40 and the connecting web 46 forming the cross strut 47A, 47B with a partial section thereof, and the strain gauge 21 is placed symmetrically with respect to the foot region 49 of the mounting base 40 on the opposite side of the bending hinge 48A, 48B to detect the maximum deformation occurring in the longitudinal direction of the housing in the absence of lateral forces.The two flexure hinges 48A, 48B may be formed by notch hinges (solid hinges) created by additional notches at the transitions to the cross struts 47A, 47B of the foot region 49, as shown diagrammatically. Flexure hinges, as known to those skilled in the art, form a flexible mechanism for increasing the detectable deformation, which is why general expertise is referred to.

[0037] In the design example of FIG. 4, additional connecting walls 51 are formed on both sides between the fixed seat 40 and the outer ends 50A, 50B of each cross member 47A, 47B or the adjacent side wall 42. Each connecting wall 51 has a thickness at least 30% less than the thickness of the side wall 42 and / or bending support to reduce the impact of the connecting wall 51 on the bending support 47A, 47B and bending hinges 48A, 48B. For further isolation, each connecting wall 51 is provided with a semicircular radius 52 or at least one crease (not shown). When the vehicle wheels are subjected to different loads, for example due to different heavy or unevenly distributed payloads, the rim portions of each vehicle wheel undergo different deformations, resulting in different deformations of the respective bending support 47A, 47B to which the strain gauges 21 are assigned. The sensor signals of each strain gauge 21, connected to the electronic circuit 20 in a suitable manner known to those skilled in the art, can be compared to reference values, for example, from a look-up table, which are predetermined for each vehicle in an unloaded state as well as for other predetermined conditions. By correlation with these data, the load forces can be determined and, for example, critical loads or load conditions can be reported to the driver. At the same time, the load data determined by the load sensing device can be supplied to other systems, as initially explained with reference to the state of the art.

[0038] The design example of the monitoring device 110 shown in Figure 5 has essentially the same structure as the previous design examples. Also, here, the strain gauges 121 are assigned to a pair of cross struts 147A, 147B, and their bending capacity significantly increases in response to deformation of the rim portion due to the flexible hinge 148 as a compliant mechanism when the mounting seat 140 transitions to the cross struts 147A, 147B. The only difference from the previous design is that there is no additional connection between the outer ends 150A, 150B and the load sensing mounting seat 140 in the mounting zone 112. However, the sensor housing 111 at the mounting seat 141 or the mounting zone 113 is designed identically to the previous design examples.

[0039] 6 and 7 show another example of a monitoring device 210. Again, the connection between the housing 211 of the monitoring device 210 and the bottom 5 of the rim portion of the vehicle wheel, as shown schematically in FIG. 7, is via an adapter plate 30, which may have the same structure as the previous design example, and via two cap screws 215 that pass through holes 216, 217 in two fastening zones 212, 213 of the housing 211 and are removably threaded into threaded holes 33 in the adapter plate 30, thus allowing for easy installation and replacement of the monitoring device 210. The monitoring device 210 also has a bending strut 247 that extends linearly between the two fastening zones 212 and 213, symmetrically about the central axis or center of the two fastening holes 216, 217. In the illustrated design example, the bending strut 247 is arranged in the lower bottom side area inside the housing 211 near the adapter plate 30, the housing 211 forming a hood covering this area, and the printed circuit board of the electronic circuit 220 together with the battery 223 are arranged above the bending strut 247. The bending strut 247 has cylindrical widened heads 260 at both ends, which are inserted into and fixed in cylindrical receptacles 261 arranged in the foot areas of the two fastening zones 212, 213 of the housing, respectively, and aligned symmetrically with the joining line between the two centers of the fastening holes 216, 217. The strain gauges 221 measure different deflections of the bending strut 247 caused by different circumferential deformations of the rim portion.

[0040] Figure 8 shows another alternative design similar to that shown in Figure 6. Here too, two fixing zones 312, 313 with fixing holes 316, 317 for a screw or pin connection to an adapter plate are equipped at the rear with a receptacle 361 for a wide head 361 of a bending post 347. However, the bending post 347 has two arms 365A, 365B covering a roughly diamond-shaped gap, each with an intermediate section 366 extending parallel to the circumferential direction and offset laterally with respect to the direct connection line between the two fixing holes 316, 317, and connected to the respective head 361 at the end of the bending post 347 via an inclined section 367. In the middle of the two heads 360, both central sections 366 may each have a notch hinge 348 as a flexible hinge or bending hinge to increase the flexibility of the bending support in the detection area of ​​the strain gauge 321 positioned opposite the flexible hinge in the central section 366, as shown by the dashed line.

[0041] 9 to 11 again show another alternative embodiment of a monitoring device 410 fixed to the rim portion 2 of a vehicle wheel. As can be seen in FIG. 9, the monitoring device 410 comprises a housing 411 that is much longer and thinner compared to the other embodiments. As in the previous embodiment, the housing 411 is attached to the rim portion 2 of the wheel by two tapping screws 415, which pass with their shanks through respective through-holes 416 in each of the fastening zones 412, 413, and are threaded into anchor nuts 433, shown in FIG. 10, which are welded or glued to the outer periphery of the rim portion (2, FIG. 9). An optimized fastening is achieved by a washer 414 under the cap of the cap screw 415, as well as a safety sleeve in the through-holes 416.

[0042] 9 and 10, the housing 411 in the illustrated embodiment comprises a total of three sections: a central main section 411A with fastening zones 412, 413, and a bending strut arrangement 470 for detecting load data, while the electronic circuit 420 is located outside the main section 411A in a side section 411B that is circumferentially offset from the main section 411A. A battery cell for supplying energy to the electronic circuit is located in another side section 411C that is circumferentially offset from the main section 411A, making the overall monitoring device 410 much thinner than the embodiment of FIGS. 1 to 8.

[0043] The design and construction of the load post is also different as compared to the embodiment of Figures 1-8. As best seen in Figure 11, the load post, generally designated 470, is removably coupled to the fastening zones 412, 413 by a pin head portion 460 inserted from above into a receptacle 461 at the inner end of the fastening zones 412, 413. Both the pin head portion 460 and the receptacle 461 have matching cylindrical portions with radii or curvatures such that the inner radius / curvature R2 of the inside of the receptacle 461 is slightly greater than the outer radius / curvature R1 of the pin head portion 460. Additionally, the distance between the centers of the pin head portion 460 is slightly greater than that of the receptacle 461 so that a tight interference is achieved, locking the load post 470 inside the receptacle 461 between the fastening zones 412 and 413.

[0044] The load post 470 comprises, in part, a rectangular bending frame having laterally extending connecting arms 481 and longitudinally extending flexure arms 482, with strain gauges 421 attached to the longitudinally extending flexure arms 482. In the illustrated embodiment, there are four strain gauges 421 in two pairs, one pair located on the inside of the longitudinal flexure arms 482 and the other pair attached to the outside of the longitudinal flexure arms 482. However, having one pair on either the inside or outside is sufficient. Integral formed on the load post 470 between each connecting arm 481 and the pin head portion 460 are a pair of triangular-shaped connecting portions 485, each having a triangular tip 486 connected to the connecting arm 481 and a triangular-shaped base 487 to which the pin head portion 460 forms an extension.

[0045] To improve or amplify the signal output of the strain gauge 421, the bending post 470 here comprises three flexible hinges 448A, 448B, 448C on the connecting arm 481 adjacent to the triangular tip 486, two of the flexible hinges 448A, 448B are located proximate to the connecting foot of the triangular tip 486 with the connecting arm 481, and the third flexible hinge 448C is located on the opposite side of the triangular tip 486 inside the rectangular frame 480. Also, to minimize the effect of the fixation of the load post 470 in the receptacle 461 on the fastening zones 412, 413, the contact area between the pin head portion 460 and the receptacle 461 is reduced by a gap between the rounded, fork-shaped inner front of the fastening zones 412, 413 and the triangular base 486 and the pin head portion 460.

[0046] For the expert, the above description will lead to many modifications that fall within the scope of the appended claims. Some of the example embodiments show the fastening of the housing by an adapter plate, which is one preferred design option. The adapter plate can also be two-part, having two unattached plate sections, each with only one threaded hole for fastening the monitoring device with a screw or anchor pin to which one of the fastening areas of the monitoring device housing is fixed. It is also possible to form two spaced-apart zones on the rim portion, each with a threaded hole or anchor pin, and, as shown in the last embodiment, all with anchor nuts attached to the rim portion for detachably attaching the monitoring device housing to the outer periphery of the rim portion in an appropriate manner. Each fastening zone can also have several fastening points, preferably symmetrically distributed with the strain gauges of the load sensing device. However, if there are several fastening points, the measurement results may be significantly more falsified due to different clamping forces between the housing and the rim portion. Furthermore, the sensor of the present invention can also be equipped with a piezoelectric element and a power generation circuit to extend the service life of the monitoring device.

Claims

1. A vehicle wheel equipped with a monitoring device (10) including: a housing (11) rotatably arranged together with a rim portion (2) of the vehicle wheel; an electronic circuit (20) arranged in the housing (11) and coupled to a load detection device having a strain gauge (21) arranged in the housing for detecting a force acting on the vehicle wheel; and a transceiver coupled to the electronic circuit for transmitting load data detected by the load detection device to a component external to the vehicle wheel, the housing (11; 211; 311, 411) has two fastening zones (12, 13; 212, 213; 312, 313; 412, 413) spaced apart from each other and connected to each other via at least one bending strut (47A, 47B; 247; 347; 470) connected to both fastening zones as components of the load detection device, and at least one pair of strain gauges (21; 221; 321; 421) is arranged on the bending strut between the fastening zones to detect deformation of the bending strut caused by a load force, 1. A vehicle wheel, comprising: a housing (11) having a cavity covered by housing walls (42, 43, 46) for enclosing and receiving the electronic circuit (20), and wherein the at least one bending strut (47A, 47B; 247; 347) is arranged inside the cavity.

2. 2. A vehicle wheel according to claim 1, characterized in that a one-piece or multi-piece adapter plate (30) whose underside (31) is adapted to the curvature of the rim portion (2) is fastened to the radially outer peripheral surface of the rim portion (2), and the housing of the monitoring device having the spaced-apart fastening zones is fastened to a cover surface (32) of the adapter plate formed away from the underside (31) of the adapter plate by means of a detachable screw connection (15) or a pin connection.

3. 2. The vehicle wheel according to claim 1, characterized in that tapped holes or anchor pins or anchor nuts (433) are formed on or fixed to the radially outer peripheral surfaces of the rim portions spaced apart from one another in the circumferential direction, and on the tapped holes or anchor pins or anchor nuts (433) the housing of the monitoring device is fastened or fastenable to the spaced apart fastening zones.

4. A monitoring device for a vehicle wheel, comprising: a housing (11; 211; 311) rotatably fastenable on a drop bed of a rim portion of the vehicle wheel; an electronic circuit (20; 120) arranged in the housing and having strain gauges (21; 221) for detecting forces acting on the vehicle wheel; and a transceiver coupled to the electronic circuit for transmitting load data detectable by a load detection device to a component external to the vehicle wheel, 1. A monitoring device comprising: a housing (11; 211; 311; 411) having two fastening zones (12, 13; 212, 213; 312, 313; 412, 413) spaced apart from one another and connected to one another via at least one bending strut (47 A, 47 B; 247; 347; 470) connected to both fastening zones as components of the load detection device; and at least one pair of strain gauges (21; 221; 321; 421) fastened to the bending strut between the fastening zones for detecting deformation of the bending strut caused by a load force.

5. 5. The monitoring device according to claim 4, characterized in that each fastening zone (12, 13; 212, 213; 312, 313) has at least one through-hole (16, 17; 216, 217; 316, 317) for a pin or a screw connection, the through-holes (16, 17; 216, 217; 316, 317) being arranged symmetrically with respect to the bending strut or struts.

6. 5. A monitoring device according to claim 4, characterized in that the housing (11) has a cavity covered by housing walls (42, 43, 46) for enclosing and receiving the electronic circuit (20), and the at least one bending strut (47A, 47B; 247; 347) is arranged inside the cavity or the at least one bending strut bounds the cavity.

7. 7. A monitoring device according to claim 6, characterized in that a single bending strut (247; 347) is arranged between the centers of the fastening zones and / or fastening holes, said strut being located symmetrically with respect to the imaginary connection line between the fastening holes, and said bending strut is assigned only one pair of strain gauges.

8. 8. A monitoring device according to claim 7, characterized in that the bending strut (347) is formed with two arms partly between the fastening zones and / or between the centers of the fastening holes, one strain gauge (321) being associated with each arm of the bending strut.

9. 8. A monitoring device according to claim 7, characterized in that the bending strut or struts are detachably coupled to the fastening zones via cylindrically enlarged heads (260; 360) at the strut ends, which are inserted into associated cylindrical receptacles (261; 361) at the fastening zones (212, 213; 312, 313) transversely to the extension direction of the bending strut, or the strain gauges (221) are arranged in the bending strut portions adjacent to or opposite to the bending hinges (348) integrally formed on the bending strut.

10. 5. A monitoring device according to claim 4, characterized in that the bending struts are designed adjacent to one of the fastening zones (12; 112), each lateral strut being designed as a pair of lateral struts (47A, 47B; 147A, 147B) extending perpendicularly to the direction of offset between the two fastening zones (12, 13), and a strain gauge (21) is assigned to each lateral strut.

11. 11. A monitoring device according to claim 10, wherein respective flexure hinges (48A, 48B; 148) integrally formed with the housing are provided between the transverse struts (47A, 47B) and the fastening zones (12).

12. The fastening zone (12) disposed adjacent to the pair of lateral struts has a single through-hole (16), and the end (50) of the lateral strut of the pair of lateral struts is connected to the other fastening zone (41) via a wall web (42); 12. A monitoring device according to claim 11, characterized in that the fastening zones (12) arranged adjacent to the pairs of transverse struts are designed as mounting seats (40) that taper symmetrically relative to the flexural hinges (48A, 48B).

13. 4. Vehicle wheel according to claim 1, 2 or 3, characterized in that the bending strut is designed as a deformation amplifier, the bending strut comprising a bending or flexible hinge for amplifying the deformation of the bending strut caused by the load forces acting on the wheel.

14. 5. The monitoring device according to claim 4, characterized in that the bending strut (470) comprises in part a rectangular bending frame (480) having transverse connecting arms (481) and longitudinal bending arms (482), the transverse connecting arms (481) extending perpendicular to the offset direction between the two fastening zones (412, 413), and a strain gauge (421) of strain gauges being assigned to each of the longitudinal bending arms (482).

15. 15. The monitoring device according to claim 14, characterized in that the bending strut (470) with the rectangular bending frame (480) is detachably coupled to the fastening zones (412, 413) by means of the bending strut (470) having one end fixed to the transverse coupling arm (481) and the other end provided with a pin head portion (460) insertable into a receptacle (461) of the fastening zone (412, 413).

16. 16. A monitoring device as set forth in claim 15, wherein each connecting portion (487) is triangularly formed having a triangular base (487) and a triangular tip (486), the pin head portion (460) is formed in the triangular base, the triangular tip (486) is connected to the connecting arm (481), and a flexure hinge (448A, 448B, 448C) is integrally formed in the connecting arm (481) adjacent the triangular tip (486).

17. 5. The monitoring device according to claim 4, characterized in that the housing (411) of the monitoring device (410) comprises at least two sections (411A, 411B, 411C) having a main section (411A) comprising the fastening zones (412, 413) and at least one side section (411B), the bending strut (470) being arranged in the main section (411A) and the electronic circuit (420) being arranged in the at least one side section (411B).

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