Multi-component measuring wheel

The present invention relates to a multi-component measuring wheel according to the preamble of Claim first

Such a multi-component measuring wheel is known from DE 41 33 418 Known C2. The known multi-component measuring wheel is for measurement purposes integrated into a vehicle wheel and has the advantage of that without major alterations to different vehicles can be used. The actual sensor part with a is connected to the vehicle tire supporting rim ring, is a ring of several parallel to the wheel axle Stud bolts and a measuring disk, having a substantially star-shaped structure with eight radially extending, an inner ring and connecting an outer ring of the measuring disk webs having. The studs are in addition to the attachment of the measuring disc at one fixed to the rim ring auxiliary flange as axial Meßquerschnitte and are equipped with strain gauges. The radial, spoke-like webs serve as Meßstege and are also equipped with strain gauges. By this arrangement is a measurement of the force components in the x, enables y and z directions and the associated moments. A disadvantage of this multi-component measuring wheel, that it consists of is composed of a plurality of individual parts, which must be possible without tolerances mounted what high Time and costs associated.

From DE 44 30 503 C1 is a torque sensor with Dehnmeßstreifenanordnung known whose measuring body a of a in Axial plane lying annular region of a disk body is formed. The disc body has a radially the inside of the first and subsequent Meßkörperbereich radially outwardly adjoining the second Meßkörperbereich Torque transmitting part, of which the torque introductory and the other the drehmomentausleitende page for Meßkörperbereich forms. The annular region has a against the torque transmission parts smaller axial Thickness, so that it under mechanical torque action Stresses shows. This torque sensor is to determine suitable moments in automotive transmissions.

From DE 43 11 903 A1 discloses a multi-component measuring wheel with between Rim face and a wheel flange arranged transducers known, wherein the wheel flange and / or the wheel rim end face consist of a fiber composite material. wheel-side Energy and data transmission means are on the inside of a vehicle tire receiving rim well attached and extend substantially over its periphery. The connection between the rim and the wheel rim end face is performed by a production of the fiber composite material for the rim face in the previously sandblasted rim, whereby a positive connection with good adhesion arises. This configuration can in the known measuring wheel on a vehicle on the lateral outer contours addition outstanding Power and data transmission system as well as on the case required holding frames are omitted. However, connected by this embodiment a rim-specific adaptation, so that the known measuring wheel is not for use with other Wheels suitable.

DE 42 16 670 C2 is another multi-component measuring wheel is known comprising a radial / tangential connection arrangement, which hub in the radial and tangential directions, the the measuring wheel connects rigidly to the rim and in the axial direction represents a soft connection between the hub and the rim, wherein the stiffness of the connection arrangement differ in radial and tangential directions. These Construction must because of its compact design as little are considered susceptible.

A disadvantage of the prior art is due to the Variety of items caused high production and installation effort the metering wheels. It must also a large number of Strain gauges are used, whereby a high application and wiring complexity arises. Further, an unfavorable Ratio between the maximum material tensions and determine the utilization voltages for the strain gages.

Object of the invention is to provide a MehrkomponentenMeßrades arranged with a between a hub and a rim Measuring device, wherein the measuring element in the axial direction possible small building, that as little as possible from the hub and by Rim formed gear plane projects.

This object is achieved by a multi-component measuring wheel with the features of claim 1.

According to the invention is now a compact slung MehrkomponentenMeßrad for measuring forces acting between a hub and a rim Forces and torques provided that axially very small building, that of the hub by and rim formed gear plane only slightly protruding. such a Multicomponent measuring wheel is both to the test, as well as usable in everyday conditions, for example in traffic. Since the measuring element integrally and rotationally symmetric is formed, it is in a simple manner between the hub and Rim attachable. The assembly effort compared to conventional Measuring arrangements comprising a plurality of individual parts, reduced. The measuring device according to the invention and the rim Hub are modular components which when needed in a simple Way can be replaced individually.

According to a preferred embodiment of the invention, the Measuring member associated with a rim, extending substantially on radially inwardly extending annular flange, a this flange radially inwardly adjoining, substantially axially extending tubular portion, one at adjoining the tubular portion radially inwardly Intermediate, one of the intermediate radially inward subsequent annular portion and an annular on the Area radially inward subsequent, optionally connected via at least one hub adapter, the hub annular flange. Such a measuring device is easily Way manufactured in one piece and proves in practice to be very robust. At the same time here is a low voltage level material guaranteed with high measurement sensitivity. Here are the substantially axially extending tubular portion, and in itself significant radially extending annular portion 7 as Meßquerschnitte, which fitted in a conventional manner with the measuring strip be, which will be discussed in detail below. can by uniform distribution of such strain gauges therefore changes in resistance due to load are eliminated, so that outwardly only the torque-induced resistance changes be effective. By appropriate arrangement the strain gauges obtained an optimum of the corresponding Useful signal while minimizing the interference signals. In terms of the various possibilities of such interconnections strain gauges, for example, to DE 27 08 484 C2 referenced. The formed respectively as measuring cross section Sections, in contrast to the remaining regions of the Measuring element with a relatively low stiffness, so that stresses occurring effectively to derive measurement signals can be used.

Appropriately, in the connecting area between the tubular Section and intermediate an axial groove or a axial notch formed. By this measure, the axial length of the multicomponent measuring wheel further reduced will.

According to a preferred embodiment of the invention Multicomponent measuring wheel takes the axial thickness of the annular Region of the measuring element in the radial direction from the inside to from the outside. Hereby is obtained when the influence of forces or moments, a uniform stress distribution in the radial direction in the annular region, whereby the evaluation of Measurement signals applied strain gauge is simplified here.

Conveniently, the intermediate flange to a radially inwardly directed annular shoulder on. such a Shoulder area is relatively against external influences protected so that, for example, soldering terminals advantageous here mountable.

Suitably, the strain gages on the annular Range, in particular its axially inner and outer walls, and / or the tubular portion, in particular the Inside is disposed. These areas have a relatively low Rigidity, so that in this case accurate measurements can be carried out are.

Advantageously, the strain gauges each cover a Angle of 20 ° to 40 °. When using such strain gauges are easily measured signals of sufficient size obtainable. Further, the number of sufficiently accurate for Measuring strain gauges required compared to conventional arrangements reduced, thereby reducing the wiring costs.

Conveniently, the respective strain gauges of Dehnmeßstreifenanordnung connected to full or half bridges. This known per se interconnection, it is possible elongations the multicomponent measuring wheel into electrical voltages convert.

According to an advantageous embodiment, the tubular Section an inner cone and an outer cylindrical formed portion. This is a robust Connection at the radially outer flange, and a relatively low rigidity of the area of ​​the tubular section, on which the strain gauges are mounted, is guaranteed.

Advantageously, the tubular portion has a ratio Diameter / length of less than 1: 6. adherence This degree is a low axial height at the same time sufficient sensitivity where the measuring element.

Suitably, inside the multicomponent measuring wheel, in particular in the interior of the tubular portion transmission means for transmitting measuring signals recorded on a Evaluation provided. By utilizing the inner space the tubular section is a very compact construction of the Multicomponent measuring wheel achievable total.

It is preferable that the measuring means Zentrierabsätzen and / or positioning, in particular by at least a hub adapter, connectable to the hub and to the rim is. Such connection means are easy to handle, whereby the assembly work of the multicomponent measuring wheel or the replacement of components is reduced or relieved is.

A preferred embodiment of the invention will now be in detail explained with reference to the accompanying drawings. In this shows<sl><li>the only figure an axially parallel section through the invention Multicomponent measuring wheel.</li></sl>

In the single figure, the multi-component measuring wheel is in detail shown. It has a vehicle tire 30 supporting Rim ring 31, which in its cross section a conventional Vehicle corresponds. However, the multi-component measuring wheel contains no conventional wheel disk, rather, in their place a measuring element 2 provided. Concerning axle radially outward the measuring element has an annular flange 3rd Over a Number of screws 32, which holes in the annular enforce flange 3, is the measuring element 2 with the rim 31 and a rim approach 1 connected. extending from the annular flange 3 axially a tubular section. 5 This has axially inside, ie subsequently to the annular Flange 3, a cone-shaped profile, and subsequently thereto a cylindrical profile. At the end of the tubular Portion 5 is radially inward an intermediate flange 6 educated. Here, in the connecting area between the tubular Area 5 and intermediate 6 a notch 20 provided by which the effective axial length of the tubular Section 5 is enlarged. Through these measures, the rigidity of the tubular portion 5 is relatively small. Adjoining the intermediate 6 radially inward an annular region 7, which annular in another Flange 8 opens. The region 7 has, similarly to the annular portion 5, also a relatively low stiffness on, so that it has a membrane-like feature in the recording filled with measured values. Via screws 41, which bores enforce the annular flange 8, the measuring member 2 connected to Nabenadaptoren 11, 12th The Nabenadaptor 12 for its part, by means of screws 50 screwed to the hub 15th By interposing the adapters 11, 12 between the measuring member 2 and hub 15 is a use of MehrkomponentenMeßrades possible together with a plurality of wheel hubs.

The annular area 7 in cross section has a trapezoidal shape on, that is, the axial thickness of the annular region 7 receives in the radial direction from the inside from the outside. This ensures, that when exposed to forces and torques evenly over the measuring wheel tensions occurring here are distributed over the annular region. 7 The occurring Tensions by strain gauges 10 each uniformly around the circumference of the measuring element on the trapezoidal arranged extending side walls of the annular area 7 are measured. By using gauges, which in peripheral direction over an angular range of approximately 20 ° to 40 ° extend, highly accurate measurement results can be achieved. to Measurement of each force or moment components are the Strain gauges in a known manner to full or half bridges interconnected. For this purpose, on each side wall of the annular Region 7 at least four, preferably eight gauges in uniform intervals provided.

Additional strain gauges 9 are on the inside of the tubular Area 5 is formed. extend these strain gauges preferably over an angular range of 20 ° to 40 °. Here are at least 6, preferably 16 gages in distributed at uniform intervals around the circumference of the measuring element provided which also interconnected to full or half bridges are.

The measurement signals recorded on the respective strain gauges be in Meßsignalaufbereitungs- and intermediaries units 13, 14 for transmission to corresponding evaluation units prepared. For power and signal transmission to the knuckle the transmission takes place preferably by means of the transmitter in the unit 13, and in the transfer to the body by means of the transmitter in the unit 14. The unit 14 may be designed such that it in the measuring element substantially covering the outside and protects against external influences.

The intermediate 6 is a radially inwardly formed Shoulder 6a is formed, on which, for example, Soldering terminals 60 are advantageously attached.

The measuring device according to the invention is characterized by low material stress level with high sensitivity the measurement signals in.

By integrating the Meßsignalaufbereitungs- and transmission units 13, 14 in the Meßgliedgeometrie is low axial height of the multicomponent measuring wheel achievable.

The measuring device 2 by means (not shown in detail) Centering lugs, positioning pins and screws easily Manner with the hub adapter or the hub and the rim connectable. Defective items can hereby replaced in a simple manner will.