Abstract:
According to the invention, the fitting of a transponder ( 4   a ) to a flat object may be simplified, whereby the same is embodied as a transponder thread, comprising a chip ( 6 ) and an attached antenna ( 8, 10 ).

Description:
[0001]    This application claims priority of PCT application PCT/CH2006/000040 having a priority date of Feb. 23, 2005, the disclosure of which is incorporated herein by reference. 
     
    
     TECHNICAL FIELD 
       [0002]    The invention relates to a transponder thread comprising at least one transponder and to a use of the transponder thread. 
       BACKGROUND OF THE INVENTION 
       [0003]    Transponders are familiar receiving/transmitting devices which carry information and operate in accordance with the challenge-response system and operate in conjunction with a mobile or stationary reader. A transponder contains a chip and an antenna. A microelectronic component which fulfils the tasks of the transponder is a corresponding chip. In contrast to an active transponder, a passive transponder does not need a battery and accordingly has a virtually unlimited life. 
         [0004]    Such transponders exhibit the most varied technologies and are used for the most varied purposes such as, e.g. the identification of the location of a carrier or as theft protection for products in shops. They can also be used for stock keeping if the transponder contains product-specific data which are forwarded to a stock controller. 
         [0005]    It is known to connect such transponders to woven or knitted flat textile structures and is trendy. Connecting the transponder chips to a flat textile structure and arranging an antenna required for transmitting and/or receiving signals provides problems. Thus, it is known to provide a flat textile structure with antennas at which the chip is then to be attached. Such a production is very difficult, particularly because of the miniaturized components which have an order of magnitude of millimeters or fractions thereof. 
       SUMMARY OF THE INVENTION 
       [0006]    It is the object of the invention to simplify the arrangement of a transponder at a flat textile structure. 
         [0007]    The object is achieved by the transponder thread which contains at least one transponder of a chip and a connected antenna. Such a transponder thread can then be connected in a simple manner to a flat textile structure, e.g. by weaving or knitting, so that the flat textile structure, e.g. a label, is already operable after the weaving or knitting process. There is no subsequent attachment of a chip to antennas. Accordingly, the use of the transponder thread at a label in such a manner that at least one transponder is arranged at the label is also the subject matter of the invention. 
         [0008]    A transponder can have a chip with a one-piece antenna. However, the transponder thread is preferably constructed in such a manner that the antenna consists of two antenna parts between which the chip is arranged. 
         [0009]    The transponder thread can have a number of transponders arranged behind one another, in each case with a chip and a connected antenna so that the transponder thread can be processed like a normal thread during weaving or knitting. The transponder thread can consist only of combined transponders so that the chips appear to be strung up on the antenna virtually in the manner of a string of pearls. The transponders can also be arranged in or at a preferably textile basic structure. If the transponders have antenna parts which extend in one piece between their chips these must be separated in the further processing of the transponder thread. 
         [0010]    The individual transponders can also be arranged independently of one another. 
         [0011]    The antenna can consist of a conductive thread. It is possible to form the antenna from braided conductive threads. It is also possible to arrange the antenna around a thread core. 
         [0012]    The transponder thread can have the most varied shapes and have, for example, a round cross section or also a flat cross section. In the latter case, the transponder can be arranged with the chip and the antenna on one side of a basic structure. In this arrangement, it can be of advantage if the transponder thread is folded along the center line, so that the basic structure encloses the transponder with its chip and its antenna. 
         [0013]    In the production of a label, the transponder thread can be arranged as warp. It is also possible to arrange the transponder thread as weft. The transponder thread can be arranged by being woven or knitted in. It is also possible to arrange the transponder thread in the sense of a figuring weft thread floating on the rear of the label. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0014]    In the text which follows, exemplary embodiments of the invention will be described in greater detail with reference to the drawings, in which: 
           [0015]      FIG. 1  shows a first transponder thread consisting only of chips and antenna parts; in plan view; 
           [0016]      FIG. 2  shows a second transponder thread with a transponder arranged in a round basic structure, in longitudinal section; 
           [0017]      FIG. 3  shows a third transponder thread with a transponder arranged at a flat basic structure, in plan view; and 
           [0018]      FIG. 4  shows labels with thread-like transponder thread in plan view. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0019]      FIG. 1  shows a transponder thread  2  which has transponders  4   a,    4   b  hanging together virtually in the manner of string of pearls. Each transponder contains a chip  6  at which antenna parts  8 ,  10  are arranged at mutually opposite sides, which are in each case connected in one piece to the antenna parts of the adjacent transponder. The antenna parts  8 ,  10  consist, for example, of a single conductive thread or of threads braided together and have a round cross section and are open, that is to say not embedded in a basic structure. 
         [0020]      FIG. 2  shows a further transponder thread  12  with transponders  14   a,    14   b  strung together, the chips  16  and antenna parts  18 ,  20  of which are embedded in a basic structure  22 . Such a basic structure can consist, for example, of fibers spun together or of a covering of plastic. 
         [0021]      FIG. 3  shows a strip-shaped transponder thread  24  which has a strip-shaped basic structure  26  at which the transponders  28   a,    28   b  are arranged. The strip-shaped basic structure can consist, for example, of a fiber fleece or a plastic band such as, for example, a lurex thread. The antenna parts  30 ,  32  are arranged in zigzag manner between the chips  34  in order to accommodate a length of the antenna which is greater than the given length of the basic structure  26 . The antenna can be formed, for example, by etching a metal layer applied to the basic structure. 
         [0022]    The transponder threads shown in  FIGS. 1 to 3  can be worked in like normal threads in a flat textile structure, for example as weft threads or warp threads or possibly as knitting thread. As a rule, the antenna parts going through between two chips must be separated half way along as is indicated by the dot-dashed separating lines  36  in the figures. 
         [0023]    With regard to the length of the antenna parts, a flat textile structure to be produced, especially a label comprising such a transponder thread, must be configured in such a manner that the transponder present in the section of the transponder thread has an antenna, the length of which ensures adequate operation of the chip, that is to say is tuned to it. Thus, an antenna length of approx. 17 cm is needed, e.g. for transponders in the UHF band. 
         [0024]      FIG. 4  shows various labels  40   a,    40   b  in which, e.g., such a transponder thread is arranged as weft  42  or as warp  44 . As a rule, such a label will have a single transponder. However, it is also possible that a label contains two and more transponders having different properties and for different purposes. Thus, one transponder can be used, e.g. for theft protection whilst another transponder can be used for stock keeping. 
       LIST OF REFERENCE DESIGNATIONS 
       [0000]    
       
           2  transponder thread 
           4   a  transponder 
           4   b  transponder 
           6  chip 
           8  antenna part 
           10  antenna part 
           12  transponder thread 
           14   a  transponder 
           14   b  transponder 
           16  chip 
           18  antenna part 
           20  antenna part 
           22  basic structure 
           24  transponder thread 
           26  basic structure 
           28   a  transponder 
           28   b  transponder 
           30  antenna part 
           32  antenna part 
           34  chip 
           36  separating line 
           40   a  label 
           40   b  label 
           42  weft 
           44  warp