Rfid tag affixed to a tire

Abstract

An RFID tag for attaching to a tire comprises the following layers: a first polyester layer; a second polyester layer adjacent to the first polyester layer, the second polyester layer having an etched antenna and an RFID chip; and a third polyester layer adjacent to the second polyester layer. The third polyester layer surrounds a portion of the first and second layers and is heat-bonded to the tire liner.

Description

TECHNICAL FIELD

[0001] The present invention relates to RFID tags affixed to rubber-based articles (e.g., vulcanized tires, green tires, etc.), and more particularly, to RFID tags attached to the inner surface (e.g., inner liner, plies, etc.) of a tire. BACKGROUND

[0002] Manufactured articles can often be monitored during manufacture and thereafter for inventory control purposes. One conventional practice can be to apply an RFID tag label to the article, which RFID tag label includes an identifier and / or other information associated with the manufactured article.

[0003] With respect to tire manufacture, to which the present invention can be particularly applicable, identifying tires and other rubber-based articles can be problematic, particularly if the identification is to occur prior to manufacture and / or prior to completion of production. Tires and a wide range of other rubber-based articles can be subjected to one or more vulcanization processes in which the tire and / or tire components can be fused, molded, and / or cured together. Vulcanization generally modifies an uncured rubber base composition by forming a wide network of molecular crosslinks within the rubber matrix, thereby significantly increasing the strength and durability of the rubber-based article. Although numerous vulcanization techniques are known having a variety of different curing methods, all or nearly all vulcanization techniques can include applying high pressure and high temperature to a "green" (e.g., uncured, non-vulcanized, non-crosslinked, etc.) rubber-based article.

[0004] In view of these process conditions, adhesive-based RFID tags have been developed that can be applied to a green rubber-based article, such as a tire, and can tolerate the relatively high temperatures and pressures associated with vulcanization. While generally satisfactory in many respects, adhesive RFID tags can not last the life of the article and can detach from the article due to various types of stress on the article during production and after production.

[0005] Potential detachment of the RFID tag can be caused by the rigidity of the tag and the relatively flexible nature of the rubber that cannot be handled during various stages of the tire manufacturing process and when the tire is mounted on a rim. This detachment can initially begin during the vulcanization process when the mold is moved and continue immediately after vulcanization when the tire temperature is still elevated.

[0006] If the tire is released from the mold and moved (e.g., flexed), the RFID tag can immediately fall off or at least be weakened in its adhesion due to the movement. Additionally, during the process of mounting the tire on a rim, the tire, particularly the bead area, can be subjected to significant mechanical stress from the mounting machine. When the tire is in use, various road and driving stresses can cause the RFID tag to detach from the tire.

[0007] Within the tire industry, RFID tag suppliers can focus on developing better adhesives. Conversely, tire and rubber product manufacturers can experiment with RFID tag positioning by applying RFID tags in so-called "non-flexing areas" of the tire or rubber product. While these activities can reduce detachment to some extent, these activities can not be the ultimate solution. Additionally, adding RFID chips to current solutions can contribute to detachment, and positioning current RFID tags behind the metal wheel rim post-fitting can hinder the ability to read the RFID chip from a useful distance. Accordingly, an alternative that enables adhesion-based RFID tags to remain attached and operable to rubber-based items during item production (e.g., vulcanization), distribution, inventory, and item life can be useful. SUMMARY

[0008] An RFID tag for attachment to a tire according to the present invention is comprised of a first polyester layer; a second polyester layer adjacent to the first polyester layer, the second polyester layer having an etched antenna and an RFID chip; and a third polyester layer adjacent to the second polyester layer. The third polyester layer encloses a portion of the first and second layers and is affixed to the inner liner of the tire by heat.

[0009] According to another aspect of the RFID tag, the second polyester layer includes a radially outer facecoat sublayer.

[0010] According to yet another aspect of the RFID tag, the second polyester layer includes a radially inner first polyester sublayer having a thermal printed barcode image.

[0011] According to a further aspect of the RFID tag, the second polyester layer is corona tested on both faces.

[0012] According to yet another aspect of the RFID tag, the second polyester layer includes a radially inner first high temperature adhesive sublayer.

[0013] According to a further aspect of the RFID tag, the second polyester layer includes a radially inner polyamide sublayer having an etched antenna and an integrated circuit.

[0014] According to yet another aspect of the RFID tag, the second polyester layer includes a radially inner second high temperature adhesive sublayer.

[0015] According to a further aspect of the RFID tag, the second polyester layer includes a radially inner first adhesion promoter sublayer.

[0016] According to yet another aspect of the RFID tag, the second polyester layer includes a radially inner second polyester sublayer.

[0017] According to yet another aspect of the RFID tag, the second polyester layer includes a radially inner second adhesion promoter sublayer.

[0018] According to still another aspect of the RFID tag, the second polyester layer includes a radially inner third adhesive sublayer of uncured rubber-based.

[0019] According to the tire of the present invention, an RFID tag is used for attachment to the tire. The RFID tag is comprised of a first polyester layer; a second polyester layer adjacent to the first polyester layer, the second polyester layer having an etched antenna and an RFID chip; and a third polyester layer adjacent to the second polyester layer, the third polyester layer encompassing a portion of the first and second layers and being affixed to the inner liner of the tire by heat.

[0020] According to another aspect of the tire, the second polyester layer includes ultra-high molecular weight polyethylene (UHMWPE).

[0021] DEFINITIONS

[0022] As used herein and in the claims:

[0023] "axial" and "axially" refer to a line or direction parallel to the axis of rotation of the tire.

[0024] "belt structure" means at least two annular layers or plies of parallel cords, either woven or non-woven, located under the tread, not anchored to the bead, and having cords inclined with respect to the equatorial plane (EP) of the tire. The belt structure can also include plies of parallel cords inclined at a relatively low angle, serving as a limiting layer.

[0025] "breaker" means at least two annular layers or plies of parallel reinforcing cords having the same angle with respect to the equatorial plane (EP) of the tire as the parallel reinforcing cords in the carcass plies. The breaker is typically associated with bias-ply tires.

[0026] "carcass" means the tire structure excluding the belt structure, the tread, the undertread, and the sidewall rubber on the plies, but including the beads.

[0027] "casings" means the carcass, belt structure, beads, sidewalls, and all other components of the tire, excluding the tread and undertread, i.e., the entire tire.

[0028] "circumferential" and "circumferentially" mean a line or direction along the circumference of the annular tire surface parallel to the equatorial plane (EP) and perpendicular to the axial direction; it can also mean the direction of a plurality of adjacent circular curves whose radii define the axial curvature of the tread, as seen in a transverse cross-section.

[0029] "Composite" as used herein means a construction of two or more layers.

[0030] "Cut belt ply" means a belt having a width less than the width of the tread that lies flat over the carcass ply in the crown area of the tire.

[0031] "Crown" means the portion of the tire near the tread of the tire.

[0032] "Dynamical shear modulus" means the shear modulus measured according to ASTM D5992.

[0033] "Elastomer" means an elastic material that is capable of recovering size and shape after deformation.

[0034] "Equatorial plane (EP)" means the plane that is perpendicular to the axis of rotation of the tire and passes through the center of its tread; or the plane that contains the circumferential centerline of the tread.

[0035] "Hysteresis" means the dynamic loss tangent (e.g., maximum loss tangent (max tan delta)). The dynamic properties of a vulcanized material sample (4 mm thick and 400 mm 2 cylindrical test piece) are recorded in response to an alternating single sinusoidal shear stress at a frequency of 10 Hz and a temperature of 80 °C on an MTS 831 elastomer testing system. The sweep is performed at a deformation amplitude of 0.1% to 50% (outward cycle), then 50% to 0.1% (return cycle). The maximum shear modulus G max and the maximum tangent value of the loss tangent (max tan delta) in MPa are determined during the outward cycle.

[0036] "Interior" means toward the inside of the tire, and "exterior" means toward the outside thereof.

[0037] "Inner liner" means one or more layers of elastomer or other material that forms the inner surface of a tubeless tire, which contains the inflation fluid within the tire.

[0038] "Inner side" means the side of the tire closest to the vehicle when the tire is mounted on a wheel and the wheel is mounted on a vehicle.

[0039] "Lateral" means the axial direction.

[0040] "Meridian plane" means the plane that is parallel to the axis of rotation of the tire and extends radially outwardly from that axis.

[0041] "Non-directional tread" means a tread that has no preferred forward direction of travel and does not require positioning in a particular wheel position or positions on the vehicle to ensure that the tread pattern is aligned with the preferred direction of travel. In contrast, a directional tread pattern has a preferred direction of travel that requires a particular wheel alignment.

[0042] "Standard load" means a particular design inflation pressure and load assigned by an appropriate standards organization for a tire use condition.

[0043] "Outboard" means the side of the tire furthest from the vehicle when the tire is mounted on a wheel and the wheel is mounted on a vehicle.

[0044] "Cord ply" means a layer of cord reinforcement consisting of radially disposed or otherwise parallel cords coated with rubber.

[0045] "Radial" and "radially" mean directions radially toward or away from the axis of rotation of the tire.

[0046] "Radial ply construction" means one or more carcass plies, or at least one ply thereof, having reinforcing cords oriented at an angle between 65° and 90° with respect to the equatorial plane (EP) of the tire.

[0047] "Radial ply tire" means a belted or circumferentially limited pneumatic tire in which at least one ply has cords extending from bead to bead and the ply is laid at a cord angle between 65° and 90° with respect to the equatorial plane (EP) of the tire.

[0048] "Section height" means the radial distance from the nominal rim diameter to the outer diameter of the tire at the equatorial plane (EP) of the tire.

[0049] "Section width" means the maximum linear distance between the outer portions of the sidewalls of the tire parallel to the axis of the tire and located outside of the sidewalls, including the 24 hour and after inflation of the tire with the standard pressure, but without the tire being under load.

[0050] "Self-supporting run-flat" means a tire type having a structure in which the tire structure is sufficiently strong on its own to support the load of the vehicle when the tire is operated in an un-inflated condition for a limited period of time and at a limited speed. The sidewalls and inner surfaces of the tire can not collapse or crumple onto themselves due to the tire structure alone (e.g., without an internal structure).

[0051] "Side wall insert" means an elastomeric or cord reinforcement located in the sidewall area of the tire. The insert can be added to the carcass reinforcement plies and the outer sidewall rubber that forms the outer surface of the tire.

[0052] "sidewall" means the portion of the tire between the tread and the bead.

[0053] "stiffness" means the stiffness of the tire expressed as the slope of the load deflection curve at a given pressure.

[0054] "stiffness ratio" means the value of controlling belt structure stiffness divided by the value of another belt structure stiffness (when these values are determined by a fixed three point bend test that supports both ends of the cord and deflects by a load centered between the fixed ends).

[0055] "toughness" means the stress expressed as force per unit linear density of a sample without strain (grams per tex or grams per denier).

[0056] "toe guard" means the circumferentially disposed elastomeric rim contact portion of the tire axially inboard of each bead.

[0057] "tread" means the molded rubber component that, when incorporated into the tire casing, includes the portion of the tire that contacts the road when the tire is properly inflated and under standard load.

[0058] "vertical deformation" means the amount of deformation of the tire under load.

[0059] "wheel" or "hub" means the structure used to support the tire and mounted to the axle. BRIEF DESCRIPTION OF DRAWINGS

[0060] The present application will be described by way of example, and with reference to the accompanying drawings, in which:

[0061] Figure 1 is a schematic depiction of an example RFID tag for use with the present application;

[0062] Figure 2 is a schematic depiction of one attachment of an RFID tag according to the present application; and

[0063] Figure 3 is a schematic depiction of another attachment of an RFID tag according to the present application. DETAILED DESCRIPTION

[0064] The present application will now be described more fully hereinafter with reference to the accompanying drawings, in which examples of the application are shown. The application may, however, be embodied in many different forms and should not be construed as limited to the representative examples set forth herein. These examples are provided by way of example so that this disclosure will be thorough and complete, and will fully convey the scope of the application to those skilled in the art. Like reference numerals refer to like elements throughout the various figures.

[0065] RFID tags can enable various tire tracking solutions for manufactured articles, including electronically identifying supplies, such as, for example, RFID devices incorporated in / on substrates such as mesh backing / material, so that the tags can be configured to withstand the pressures, temperatures, and / or stresses associated with manufacturing (e.g., tire vulcanization) and a wide variety of uses of tires and other rubber products, while at the same time remaining operable during, after, and throughout the useful life of the articles, thereby sensing and providing unique identifier(s) and / or other information about the articles during distribution, inventory, and the life of the articles. As further disclosed below, RFID tags can be attached to and / or incorporated in sidewalls, beads, and / or inner liners of a wide variety of tires. Depending on the type of tire, the materials of the tire, and / or the use of the tire (e.g., racing tires), the thickness, surface area, and / or configuration of the different RFID tag materials can vary.

[0066] As will be appreciated, tires can be used in conjunction with the rims of vehicles in general. Rubber-based tires can utilize roadways or ground surfaces to support and provide traction for vehicles. RFID tags can be used with bias-ply tires, belted bias-ply tires, radial tires, solid tires, semi-pneumatic tires, pneumatic tires, airless tires, non-pneumatic tires, truck / bus tires, aircraft tires, agricultural tires, racing tires, and the like.

[0067] RFID tags can withstand conditions typically associated with the vulcanization process without deteriorating. As used herein, the term vulcanization can refer to heating to temperatures greater than 90 °C and up to 200 °C for a predetermined period of time, such as from at least 10 minutes up to several hours. RFID tags can generally include at least one RFID device.

[0068] RFID devices can generally include an antenna for wirelessly transmitting and / or receiving RF signals, and analog and / or digital electronics operatively connected to the antenna. RFID devices can include passive RFID devices, and / or active and / or semi-passive RFID devices including batteries and / or other power sources. The electronics can be implemented via integrated circuits (ICs) and / or microchips and / or other suitable electronic circuitry, such as, for example, communication electronics, data storage, control logic, and the like.

[0069] RFID devices can operate within a variety of frequency ranges, including, but not limited to, the low frequency (LF) range (e.g., from about 30 kHz to about 300 kHz), the high frequency (HF) and NFC (near field communication) range (e.g., from about 3 MHz to about 30 MHz), and the ultra-high frequency (UHF) range (e.g., from about 300 MHz to about 3 GHz). Passive devices can operate within any of the above frequency ranges. Specifically, for passive devices, LF systems can operate at about 124 kHz, 125 kHz, or 135 kHz, HF and NFC systems can operate at about 13.56 MHz, and UHF systems can use a frequency band from 860 MHz to 960 MHz. Alternatively, passive devices can use 2.45 GHz and / or other regions of the radio frequency spectrum. Active RFID devices can operate at about 455 MHz, 2.45 GHz, or 5.8 GHz. Semi-passive RFID devices can operate at a frequency of about 2.4 GHz.

[0070] The read range of an RFID device (i.e., the range within which an RFID reader can communicate with an RFID device) can be determined by the type of device (e.g., active, passive, semi-passive, etc.). Passive LF RFID devices (also referred to as LFID or LowFID devices) can typically be read from within about 12 inches (0.33 meters); passive HF RFID devices (also referred to as HFID or HighFID or NFC devices) can typically be read from up to about 3 feet (1 meter) away; and passive UHF RFID devices (also referred to as UHFID devices) can typically be read from about 10 feet (3.05 meters) or more away.

[0071] One factor that affects the read range of a passive RFID device is the method used to transfer data from the device to the reader (e.g., the coupling mode between the device and the reader, which can be inductive coupling or radiated / propagated coupling). Passive LFID devices and passive HFID devices can use inductive coupling between the device and the reader, while passive UHFID devices can use radiated or propagated coupling between the device and the reader.

[0072] Alternatively, in a radiative or propagative coupling application (e.g., as conventionally used by passive UHF ID devices), the reader can emit electromagnetic energy that can illuminate the device, rather than forming an electromagnetic field between the respective antennas of the reader and the device. In turn, the device can collect energy from the reader via the antenna, and the integrated circuit (IC) or microchip of the device can use the collected energy to change the load on the device antenna and reflect the changed signal back (e.g., backscatter). UHF ID devices can transmit data in a variety of different ways, such as increasing the amplitude of the reflected wave sent back to the reader (amplitude shift keying), shifting the reflected wave out of phase with the received wave (phase shift keying), and / or changing the frequency of the reflected wave (frequency shift keying). The reader can then pick up the backscattered signal and convert the changed wave into data understood by the reader and / or an attached computer.

[0073] Antennas employed in RFID devices can be influenced by a number of factors, such as the intended application, the type of device (e.g., active, passive, semi-passive, etc.), the desired read range, the device-to-reader coupling mode, and / or the operating frequency of the device. For example, since passive LFID devices can typically inductively couple with a reader, and because the induced voltage in the device antenna can be proportional to the operating frequency of the device, passive LFID devices can include a coil antenna with many turns in order to generate sufficient voltage to operate the device IC and / or microchip. In comparison, conventional HFID passive devices can include a planar spiral antenna (e.g., with 5 to 7 turns in a credit card size form factor) to provide a read range of approximately tens of centimeters. HFID antenna coils can be less expensive to produce (e.g., as compared to LFID antenna coils) because they can be fabricated using relatively inexpensive techniques (e.g., photolithography, etc.) as compared to wire winding. UHFID passive devices can radiatively and / or propagatively couple with a reader antenna, and thus can employ conventional dipole-like antennas. RFID tags for use with the present application can utilize any of the above-described RFID devices, as well as other devices not specifically mentioned.

[0074] RFID tags can advantageously be attached to the inner liner 11 of the tire 10. RFID tags can be received from a supplier in a roll, with the RFID tags attached to a release liner with uncured rubber cement. The rubber cement can have good initial tack or stickiness to uncured rubber. However, after curing / heating, the RFID tags can lose this initial tack and fall off from the inner liner 11. As Figure 1As shown in FIG. 1, a conventional roll 100 of example RFID tags 110 can include: a radially outermost face coating 111; a next radially inner first polyester layer 112 having a thermal printed barcode image (both sides are corona tested); a next radially inner first high temperature adhesive layer 113; a next radially inner polyamide layer 114 having an etched antenna and IC; a next radially inner second high temperature adhesive layer 115; a next radially inner first adhesion promoter layer 116; a next radially inner second polyester layer 117; a next radially inner second adhesion promoter layer 118, a next radially inner uncured rubber-based third adhesive layer 119; and a removable liner 101 of the roll 100 for holding the RFID tags 110, for example, prior to application to the inner liner 11.

[0075] As shown in FIG. 1, a conventional roll 100 of example RFID tags 110 can include: a radially outermost face coating 111; a next radially inner first polyester layer 112 having a thermal printed barcode image (both sides are corona tested); a next radially inner first high temperature adhesive layer 113; a next radially inner polyamide layer 114 having an etched antenna and IC; a next radially inner second high temperature adhesive layer 115; a next radially inner first adhesion promoter layer 116; a next radially inner second polyester layer 117; a next radially inner second adhesion promoter layer 118, a next radially inner uncured rubber-based third adhesive layer 119; and a removable liner 101 of the roll 100 for holding the RFID tags 110, for example, prior to application to the inner liner 11. Figure 2 and Figure 3 As shown in FIG. 2, an RFID tag 210 of the system 200 according to the present application can include only three layers: a first inward-facing polyester layer 211; a next outer second polyester layer 212 having an etched antenna and RFID chip; and an outermost third polyester layer 213. The three layers 211, 212, 213 can be secured to one another by any suitable glue and / or adhesion promoter. The first and second layers 211, 212 can provide structural integrity to the RFID tag 210, but not adhesion to the inner liner 11.

[0076] Instead of discarding the removable liner 101, the liner can be the third layer 213 itself and can be sized to properly enclose the first and second layers 211, 212 and temporarily secure to the inner liner 11 prior to curing of the tire 10. During curing, the liner 111 can at least partially liquefy during cooling and permanently adhere to the inner liner 11. Such a liner 213 can be constructed of any suitable polymeric material, such as ultra-high molecular weight polyethylene (UHMWPE). The liner 213 can be sealed to the inner liner 11 completely around the first and second layers 211, 212, or left with an opening 215 to form a pocket for proper replacement / removal of the first and second layers 211, 212. Figure 3 Figure 2

[0077] Variations of the application are possible as provided in the description of the application herein. While certain representative examples and details have been shown for purposes of illustrating the innovative application, it will be apparent to those skilled in the art that various changes and modifications can be made therein without departing from the scope of the application. It is therefore intended that the application not be limited to the particular examples disclosed but cover modifications and equivalents falling within the scope of the application as defined by the appended claims.​​

Claims

1. An RFID tag for attaching to a tire, the RFID tag comprising the following layers: First polyester layer; A second polyester layer adjacent to the first polyester layer, the second polyester layer having an etched antenna and an RFID chip; as well as A third polyester layer adjacent to the second polyester layer, the third polyester layer surrounding a portion of the first and second polyester layers and being heat-fixed to the tire liner; The third polyester layer is sealed to the liner and has an opening to form a recess for proper replacement / removal of the first and second polyester layers.

2. The RFID tag according to claim 1, wherein, The second polyester layer includes a radially outermost surface coating sublayer.

3. The RFID tag according to claim 1, wherein, The second polyester layer includes a radially inner first polyester sublayer having a thermally printed barcode image.

4. The RFID tag according to claim 1, wherein, The second polyester layer was subjected to corona testing on both sides.

5. The RFID tag according to claim 1, wherein, The second polyester layer includes a radially inner first high-temperature adhesive sublayer.

6. The RFID tag according to claim 1, wherein, The second polyester layer includes a radially inner polyamide sublayer with an etched antenna and integrated circuit.

7. The RFID tag according to claim 5, wherein, The second polyester layer includes a radially inner second high-temperature adhesive sublayer.

8. The RFID tag according to claim 1, wherein, The second polyester layer includes a radially inward first adhesion promoter sublayer.

9. The RFID tag according to claim 3, wherein, The second polyester layer includes a radially inner second polyester sublayer.

10. The RFID tag according to claim 8, wherein, The second polyester layer includes a radially inward second adhesion promoter sublayer.

11. The RFID tag according to claim 3, wherein, The second polyester layer includes a third adhesive sublayer of radially inward uncured rubber-based material.

12. A tire comprising an RFID tag for attaching to the tire, the RFID tag comprising the following layers: First polyester layer; A second polyester layer adjacent to the first polyester layer, the second polyester layer having an etched antenna and an RFID chip; as well as A third polyester layer adjacent to the second polyester layer, the third polyester layer surrounding a portion of the first and second polyester layers and being heat-fixed to the tire liner; The third polyester layer is sealed to the liner and has an opening to form a recess for proper replacement / removal of the first and second polyester layers.

13. The tire according to claim 12, wherein, The second polyester layer comprises ultra-high molecular weight polyethylene (UHMWPE).

Images