Abstract:
A product management system and method for reading an electronic identification tag secured to a manufactured product is provided and includes a portal having a portal opening positioned and dimensioned to permit the product to be transported through the portal opening; a flexible curtain consisting of an array of flexible, transparent strips pivotally suspended at the portal to depend downward into the portal opening, the curtain strips within the portal opening having an antenna incorporated therein. The curtain strips are positioned for contacting engagement with the manufactured product or each product within a stack of such products as the product/stack passes through the portal opening. An intimate contacting engagement by antenna-bearing strips with each product enables receipt of electronic data transmission from the electronic identification tag of each of the products as the products move through the portal opening.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention relates generally to tires having a readable RFID identification tag incorporated therein and, more specifically, to a reader portal for reading RFID tags in such tires. 
       BACKGROUND OF THE INVENTION 
       [0002]    It is useful to incorporate an RFID identification tag into a tire in order to enable an identification of the tire throughout the useful service life of the tire. Such tags age affixed to the tire either during pre-cure tire build or during a post-cure tag attachment procedure. Such tires are manufactured by generally conventional factory techniques and are shipped from the factory either to a designated automobile original equipment manufacturer (OEM) or to a tire dealer for use as a replacement tires. In the course of post-manufacture handling, the tires are typically stacked and moved by forklift trucks with a metal clamp to hold the stack of tires. Tires are then moved through a warehouse and pass either through dock doors for loading onto trailers/trucks or move through alternative warehouse openings to other shipping points of deportation. 
       SUMMARY OF THE INVENTION 
       [0003]    In one aspect of the invention a product management system and method for reading an electronic identification tag secured to a manufactured product is provided. The system includes a portal having a portal opening positioned and dimensioned to permit the product to be transported through the portal opening; a flexible curtain pivotally suspended at the portal to depend downward into the portal opening, the curtain within the portal opening being positioned for contacting engagement with the manufactured product as the one product passes through the portal opening. An antenna is secured to the flexible curtain and swings with the curtain into a position operatively accessible for an electronic data transmission from the electronic identification tag as the one product moves through the portal opening. 
         [0004]    In another aspect, the system includes an electronic reader coupled to receive the electronic data transmission from the curtain-mounted antenna. 
         [0005]    According to a further aspect, the antenna is composed of a flexible, transparent material composition and is secured within the flexible curtain. 
         [0006]    The curtain includes a multiple vertically suspended, independently moving, flexible strips, in a further aspect, the strips having a mutual spacing and position within the portal opening to substantially ensure that at least one of the flexible strips contacts the manufactured product or each product within a vertical stack of such products as the product/stack moves through the portal opening. 
       Definitions 
       [0007]    “Aspect ratio” of the tire means the ratio of its section height (SH) to its section width (SW) multiplied by 100 percent for expression as a percentage. 
         [0008]    “Asymmetric tread” means a tread that has a tread pattern not symmetrical about the center plane or equatorial plane EP of the tire. 
         [0009]    “Axial” and “axially” means lines or directions that are parallel to the axis of rotation of the tire. 
         [0010]    “Chafer” is a narrow strip of material placed around the outside of a tire bead to protect the cord plies from wearing and cutting against the rim and distribute the flexing above the rim. 
         [0011]    “Circumferential” means lines or directions extending along the perimeter of the surface of the annular tread perpendicular to the axial direction. 
         [0012]    “Equatorial Centerplane (CP)” means the plane perpendicular to the tire&#39;s axis of rotation and passing through the center of the tread. 
         [0013]    “Footprint” means the contact patch or area of contact of the tire tread with a flat surface at zero speed and under normal load and pressure. 
         [0014]    “Groove” means an elongated void area in a tread that may extend circumferentially or laterally about the tread in a straight, curved, or zigzag manner. Circumferentially and laterally extending grooves sometimes have common portions. The “groove width” is equal to tread surface area occupied by a groove or groove portion, the width of which is in question, divided by the length of such groove or groove portion; thus, the groove width is its average width over its length. Grooves may be of varying depths in a tire. The depth of a groove may vary around the circumference of the tread, or the depth of one groove may be constant but vary from the depth of another groove in the tire. If such narrow or wide grooves are substantially reduced depth as compared to wide circumferential grooves which the interconnect, they are regarded as forming “tie bars” tending to maintain a rib-like character in tread region involved. 
         [0015]    “Inboard side” means the side of the tire nearest the vehicle when the tire is mounted on a wheel and the wheel is mounted on the vehicle. 
         [0016]    “Lateral” means an axial direction. 
         [0017]    “Lateral edges” means a line tangent to the axially outermost tread contact patch or footprint as measured under normal load and tire inflation, the lines being parallel to the equatorial centerplane. 
         [0018]    “Net contact area” means the total area of ground contacting tread elements between the lateral edges around the entire circumference of the tread divided by the gross area of the entire tread between the lateral edges. 
         [0019]    “Non-directional tread” means a tread that has no preferred direction of forward travel and is not required to be positioned on a vehicle in a specific wheel position or positions to ensure that the tread pattern is aligned with the preferred direction of travel. Conversely, a directional tread pattern has a preferred direction of travel requiring specific wheel positioning. 
         [0020]    “Outboard side” means the side of the tire farthest away from the vehicle when the tire is mounted on a wheel and the wheel is mounted on the vehicle. 
         [0021]    “Radial” and “radially” means directions radially toward or away from the axis of rotation of the tire. 
         [0022]    “Rib” means a circumferentially extending strip of rubber on the tread which is defined by at least one circumferential groove and either a second such groove or a lateral edge, the strip being laterally undivided by full-depth grooves. 
         [0023]    “Sipe” means small slots molded into the tread elements of the tire that subdivide the tread surface and improve traction, sipes are generally narrow in width and close in the tires footprint as opposed to grooves that remain open in the tire&#39;s footprint. 
         [0024]    “Tread element” or “traction element” means a rib or a block element defined by having a shape adjacent grooves. 
         [0025]    “Tread Arc Width” means the arc length of the tread as measured between the lateral edges of the tread. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0026]    The invention will be described by way of example and with reference to the accompanying drawings in which: 
           [0027]      FIG. 1  is a perspective view of a known RFID tag. 
           [0028]      FIG. 2A  is a perspective cut-away view of tire showing upper side wall RFID tag location. 
           [0029]      FIG. 2B  is a perspective cut-away view of tire showing apex area RFID tag location. 
           [0030]      FIG. 3  is a perspective view of RFID tag laminated between opposed strips. 
           [0031]      FIG. 4  is a perspective view of RFID tag locations for tags used in  FIG. 3 . 
           [0032]      FIG. 5A through 5D  are plan views of wiring embodiments for the hanging antennas. 
           [0033]      FIG. 6A  is an exploded perspective view of flexible hanging antenna. 
           [0034]      FIG. 6B  is an exploded perspective view of antenna showing bracket placement. 
           [0035]      FIG. 7  is a perspective view of top portion of hanging flexible antenna assembly. 
           [0036]      FIG. 8  is a perspective view of top portion of hanging flexible antenna assembly showing cable connectors. 
           [0037]      FIG. 9  is a perspective view of forklift with tire stack and flexible hanging antennas. 
           [0038]      FIG. 9B  is a Perspective view of forklift pushing tires through flexible hanging antennas for scanning. 
           [0039]      FIG. 10  is a schematic view of tire stack being detected by flexible hanging antennas. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0040]    Referring to  FIGS. 1 and 3 , the use of RFID tags such as tag  10  in products for the purpose of enabling an electronic identification of the product is well know. Such tags are affixed to or embedded into a product in a manufacturing or post-manufacturing procedure and remain with the product during post-manufacture handling, shipping, the supply chain, and even use of the product throughout its useful service life. Because, in certain products such as tires, RFID tags may be embedded into the tire during tire manufacture, the RFID tags may have a limited performance range, making it necessary that a reader antenna be brought into close enough proximity to excite the tag. An antenna portal system is disclosed as follows which provides sufficient RF power to excite RFID tags, mechanical robustness to withstand years of use, ease of installation and compatibility with existing RFID readers/eNodes. While the particular reader portal for reading RFID tags is shown in the context of tire manufacture and management, it will be appreciated that the invention is not so limited. Other products may employ the reader portal teachings herein set forth in a variety of manufacturing applications. 
         [0041]      FIGS. 1 and 3  show an RFID tag  10  constructed having an electronic package  12  mounted to a substrate  14  with contacts  16  of the RFID electronics coupled to dipole antennas  18 ,  20 . The tag construction  10  is sandwiched between two strips  22 ,  24  of protective material such as plastic, with the tag  10  affixed by a layer of adhesive  26  between the strips  22 ,  24 . The completed tag assembly is suitable for incorporation into myriad products including a tire  28  as shown in  FIGS. 2A and 2B . The tire  28  is of conventional construction having a pair of sidewalls  20  extending from dual bead components  24  to a tire tread  36 . A pair of chafer components  32  are positioned adjacent respective beads  24 . The tire is further constructed having one or more reinforcement plies  38  and an inner liner component  40  which surrounds the tire air cavity. 
         [0042]    The tag  10  may be affixed in several manners and at several alternative locations on the tire  28 .  FIG. 2A  shows a placement of the tag  10  against a reinforcement ply  38  during tire build. Alternatively, the tag  10  may be placed during tire construction against a chafer component  32  as shown in  FIG. 2B . In a post-manufacture attachment, the tag  10  may be placed and affixed by adhesive to the tire in several locations such as location “A” against inner liner  40  sidewall region as shown in  FIG. 4  or location “B” against the inner liner crown region. Location “C” shown the incorporation of the tag against the chafer component as shown in  FIG. 2B . One or more tags may be incorporated into the tire in the locations shown. 
         [0043]    With reference to  FIGS. 9A and 9B , a system for tracking tires throughout the manufacturing and supply chain channels is shown. Tires equipped with RFID tags are generally transported within manufacturing facilities in groups, such as stacked up to ten feet high on a forklift. It is desirable but technically difficult to be able to track tires passing through portals while stacked on forklifts because the carbon in tires may cause the effective RFID tag performance range to degrade significantly. This requires placing antennas very close to tires. The system and method represented in  FIGS. 9A and 9B  overcomes the limited read distance of RFID tags in tires by providing a pass-through portal  42  in which a reading of tire based RFID tags is achieved. The portal  42  includes a pass-through opening  44 . A flexible antenna curtain  46  hangs into the opening  44  and is constructed from multiple side-by-side hanging antenna strips  48 . The antenna strips  48  are wired at  50  to an RFID reader  52  located proximally or remotely from the pass-through portal  42 . A stack of tires  28  may be hoisted (arrow  54 ) by a fork-lift  56  and oriented to pass through the opening  44 . The tires  28  are equipped with one or more RFID tags as described above, located in the tire or on one or affixed to one or more tire surfaces. 
         [0044]      FIG. 9B  shows the stack of tires  28  transported through the portal opening  44  in direction  58 . The opening  44  is sized to closely admit and pass through the stack and fork lift  56 . The curtain  46  formed by antenna strips  48  is sized to occupy a large percent of the opening  44  such that engagement of each tire  28  within the stack by one or more of the antenna strips  48  is ensured. Thus, the antenna strips  48  will be placed into physically close proximity to the embedded or attached tire tags. Proximal location of the strips  48  to the tags ensures a positive and reliable reading of the tags by the antenna strips  48 . 
         [0045]    It is contemplated that multiple strips  48  will be employed within the portal opening to form the curtain  56 . For example, four strips may be placed in the portal, each strip being nine inches wide with nine inch spacing between the strips. The curtain  56  will thus occupy and provide over five feet of coverage. As shown, the portal  42  is defined by vertical support posts  60 ,  62  and an upper cross-beam  64  supported by posts  60 ,  62 . The opening  44  occupies the spacing between the posts, cross-beam and the floor surface. As the tires move through the portal, the tires will brush against and push back one or more of the curtain strips  48 . This mobility will provide diversity that will ensure that each tag will move through at least one strong read field and likely several strong read fields. The antenna curtain  56  formed by the antenna strips  48  is constructed to be flexible and easily swung by direct engagement with the moving stack of tires. Moreover, the curtain strips are easily hung and readily connected to the system RFID reader/eNode  52  as will be explained. 
         [0046]    Referring to  FIGS. 5A  through D,  6 A,  6 B and  7 , each curtain antenna strip  48  is constructed as a conductive loop antenna array  70  sandwiched between layers  66 ,  68  composed of non-conductive material such as plastic. A suitable adhesive may be employed to affix the layers  66 ,  68  together with the antenna array  70  between. Layers  66 ,  68  may be formed of any suitable material such as clear, flexible PVC, polyester, or a composite combination of both. The material selected for the strips is preferably transparent or semi-transparent to enable light projection through the portal opening as well as visibility through the curtain by the equipment operator. The antenna radiating arrays  70  within the strips  48  are composed of thin conductive metal of sufficient physical strength to withstand cyclical flexing by the curtain as well as functionally capable of providing the requisite radiating properties to generate a field of adequate strength. 
         [0047]    Leads  72  access the radiating antenna loop elements  70 . The loop elements  70  may be arranged in any suitable array such as the alternative schematic antenna embodiments shown in  FIGS. 5A  through D, interconnected by conductive wiring  82 . The leads  72  are directed to a junction box  74  having a screw threaded coupling attachment. To construct the hanging curtain  46 , the antenna strips  48  are provided with a spaced apart series of assembly apertures  78 ,  80  extending across an upper edge of each layer  66 ,  68  respectively. As shown in  FIG. 6B , the upper edges of layers  66 ,  68  are positioned between bracket strips  84 ,  86  having through-hole arrays  88 ,  90  corresponding to the placement of holes through the layers  55 ,  58 . Assembly screws  92  extend through the co-aligned apertures  88 ,  90  and layer apertures  78 ,  80  to complete assembly of the support bracket of each curtain strip. The lower bracket strip  86  provides extension flanges  94 ,  96  at opposite ends, each arm having an aperture  98  therethrough. 
         [0048]    The upper end of a representative, completed antenna strip  48  is shown in  FIG. 7 . The curtain strips  48  are assembled to a cross frame beam  108  by screw hardware (not shown) extending through flange apertures  98  as will be seen from  FIGS. 8 and 9A . The strips  48  are hung adjacent with a space between adjacent strips in a spaced array along the beam  108 . 
         [0049]    The strips flexible pivot about the frame attachment at the top edge, and swing freely in the portal opening. Conduits and connectors extend from each strip to the reader  52  as will be seen from  FIG. 8 . A T-connector  100  couples with conduits  102 ,  104 ,  106  by means of screw fittings, and the conduit  102  connects the assembly of  100 ,  102 ,  104 ,  106  to the screw threaded collar  76  of box  74 . Electrical connection of the reader to the antenna circuitry through the assembled conduits  100 ,  102 ,  104 ,  106  is thus established. 
         [0050]      FIG. 10  shows in schematic form the stack of tires of  FIG. 9  engaging the antenna strips  48  as the stack is moved through portal opening  33 . The RFID tag(s) attached to each tire, regardless of their attachment, are each brought into a reading proximity with at least one field generated by the antenna strips  48 . Because of the number of antenna strips employed, their mutual spacing, the curtain  46  may be configured to occupy a substantial area of the opening  44 , thus creating a high probability that the RFID tag(s) carried by the stack of tires will move through at least one strong read field, and likely several strong read fields. Because the tag likely passes through multiple read fields, redundant readings of the tag may occur which will enhance system read reliability and performance. 
         [0051]    Thus, the reader antenna within strips  48  are located close enough to excite the tag. Moreover, the antenna strips  48  are constructed to protectively sandwich the antenna circuitry between dual layers of laminate strips  22 ,  24 , rendering the assembled strips  48  mechanically robust and capable of withstanding repeated flexing cycles. The strips  48  through the frame attachment described above are readily installed within a portal opening in at manufacturing or warehouse location or any other stop in the distribution channel. The antenna system is compatible with conventional and commercially available readers/eNodes, making the pass-through product management system cost effective to implement, service and operate. While tires are the exemplary products used in the foregoing description, the system may be adapted and used for other product categories where transportation of products carrying a RFID tag(s) are routed through a portal opening in the course of manufacture or subsequent distribution. 
         [0052]    Variations in the present invention are possible in light of the description of it provided herein. While certain representative embodiments and details have been shown for the purpose of illustrating the subject invention, it will be apparent to those skilled in this art that various changes and modifications can be made therein without departing from the scope of the subject invention. It is, therefore, to be understood that changes can be made in the particular embodiments described which will be within the full intended scope of the invention as defined by the following appended claims.