FR2781071A1 - Electromagnetic tag recognized by antitheft barrier - Google Patents

Abstract

The tag has a thin plate made of plastics (4) containing a buried thin tracer wire (2), capable of being detected by the barrier at the door of a department store. The tag is generally rectangular in shape with a tang (6) at one end. The tang has an aperture (7) in it to accommodate a wire loop (11) attaching the tag to a piece of merchandize (10). The wire runs along the longitudinal axis of the tag, which has identification letters and numbers printed on it.

Description

The invention relates to deterrence against theft, particularly in

self-service stores.

  We know that there are recognizable devices when they pass through anti-theft barriers arranged for example between the boxes or in front of the doors of these stores, their recognition triggering a

alarm.

  The invention relates to such a device which is convenient, reliable and practical.

  To this end, it offers a device recognizable by an anti-theft barrier, characterized in that it comprises a plate of flat plastic material.

  and thin in which is embedded an electronically detectable tracer wire

  magnetically by said barrier, said plate having at least one part whose width, measured transversely to said tracer wire, is greater than 1 cm. Of course, the length of the plate, measured along the tracer wire, is provided so that the latter has at least the minimum length required (set by the supplier) for detection by anti-theft barriers, this minimum length being for example 40 to 70 cm next

the separation of the barriers.

  Because of its width, the plate of the device according to the invention is visible or in any case easily identifiable, unlike conventional devices which coat a tracer wire (section of narrow adhesive tape or thin plastic stick), while that unlike the prior devices intended to be visible, the device according to the invention is not very bulky, because

  the plate is flat and thin, but is capable of offering the same deterrent effect.

  According to preferred characteristics, the device according to the invention

  includes a marking label affixed to said plate.

  The latter thus serves not only to coat the tracer wire, but also as a marking support, the device according to the invention then having both a function of protection against theft and an information function, in particular on the characteristics of the article to which the device is attached, on

its references and its price.

  It will be observed that by providing that the plate serves as a marking support, the device according to the invention is necessarily seen by people interested in the article to which it is attached, even if the volume of this device

remains relatively weak.

  According to alternative preferred characteristics for the same reasons, the device according to the invention has written marking signs

directly on the turntable.

  According to other preferred characteristics, the plate of the device according to the invention comprises a hole for passage of a means of attachment to an article to be protected against theft. The fixing of the plate to the article to be protected is thus particularly safe, since to remove the tracer wire from the article to which it is fixed, it is necessary to open or break the fixing means or else break the plate at the level of the passage hole , which is a more delicate operation to carry out than peeling off the adhesive tape or removing the stick of material

  plastic which coats the tracer wire in the prior devices.

  According to other preferred characteristics, in particular for reasons of convenience of manufacture and use, said plate comprises a generally rectangular part to which is attached a projecting tab in which is formed at least one through hole of a means of attachment to an article to be protected against theft. The invention also relates, in a second aspect, to a process for preparing the device described above, which is characterized in that it includes the operation of preparing a flat and thin plastic element in which said tracer wire is embedded, said element having a width, measured transversely to said tracer wire, greater than 1 cm; then the operation

  to cut said plate from said element.

  The plate of the device according to the invention is thus obtained so

  particularly simple, convenient and economical.

  Preferably, said operation of preparing an element comprises

  The operation of extruding said plastic material.

  Such a method of preparation gives excellent results, in particular

  in terms of value for money.

  Preferably, alternately, said operation of preparing an element comprises the operation of laminating two sheets made of said material

  plastic, between which said tracer wire sandwiched.

  Such a method of preparation also gives excellent results.

  The invention also relates to an alternative method for preparing a device as set out above, characterized in that it includes the operation of preparing said plate by overmolding said tracer wire with said

plastic material.

  The description of the invention will now be continued with the description.

  of an exemplary embodiment, given below by way of illustration and not limitation, with reference to the accompanying drawings. On these: - Figure 1 is a plan view of a section of the strip used to prepare the plate of a device according to the invention; - Figure 2 is a plan view of such a plate obtained by cutting the strip shown in Figure 1; FIG. 3 shows the device comprising this plate fixed by a link on an article to be protected against theft; - Figure 4 shows a variant of this device; - Figure 5 is a partial plan view of a plate used alternately to prepare the plate of a device according to the invention; - Figure 6 is a plan view of a plate obtained by cutting the plate shown in Figure 5; and - Figure 7 is a partial view in elevation-section, taken in the

  plate of FIG. 6, along the tracer wire which it comprises.

  The strip 1 shown in FIG. 1 is obtained by extrusion of a plastic material with insertion, midway between the edges of the die, of a tracer wire 2 which is thus embedded in the mass of the plastic material, oriented parallel to the edges of the strip and arranged midway between these edges. In the illustrated example, the strip I has a width of 42 mm and a

thickness of about 1 mm.

  To obtain the plate of a device according to the invention, the strip is cut using a press along contour 3 shown in phantom on the

figure 1.

  The plate 4 obtained (FIG. 2) has a part 5 of generally rectangular shape and a projecting tab 6 connecting to part 5 in alignment with the tracer wire 2, the tab 6 being arranged symmetrically on the side and

  on the other side of this wire, a through hole 7 being formed in the center of the tab 6.

  The width of the rectangular part 5 is here about 40 mm, the margin of 1 mm existing on each side between the longitudinal edges of the part 5 and the edges of the strip 1 making it possible to avoid finding on the plate

  4 possible manufacturing imperfections of the edges of the strip 1.

  The length of the continuous tracer wire lying between the hole 7 and the edge of the part 5 opposite the tab 6, is here about 62 mm, which is greater than the minimum required to be detectable electromagnetically by

an anti-theft barrier.

  It will be observed that the fact that the tab 6 contains the wire 2 makes it possible to have a continuous section of this wire which is longer than the part

rectangular 5.

  On the rectangular part 5 of the plate 4 is stuck a label 8 (figure 3) carrying information 9 relating to article 10, here a garment, which must be protected against theft, the fixing of the plate 4 to the garment by means of a metal cable 11 closed in a loop by crimping a ring not shown, the fixing cable 11 passing through the hole 7 of the tab 6 and through the hole 12 of the tongue 13 for drawing a closing at

garment slide 10.

  In the 4 ′ variant of the plate 4 shown in FIG. 4, the lug 6 is replaced by a lug 6 ′ wider and having two through holes 7 ′ while the rectangular part 5 is replaced by a part 5 ′ of the same dimensions but on which the information of

9 'marking.

  The holes 7 'are formed on either side of the tracer wire 2 so

  that it extends over the entire length of the plate 4 '.

  Due to the fact that there are two holes 7 ′, it is possible to fix the plate 4 ′ on the object to be protected against theft so that this plate keeps its positioning, by using a passing link 11 ′ as fixing means. in

  the two holes 7 'and tightly encircling the article to be protected.

  The signs forming the marking information 9 ′ are here written by printing, but any other writing method is suitable, in particular by engraving. The plate 16 shown in FIG. 3 is obtained by rolling two plastic sheets between which three tracer wires 2 'are sandwiched, which are arranged parallel to the longitudinal edges of the

  plate 16 and equidistant from each other.

  In the example illustrated, the plate 16 has a width of 140 mm and a

thickness of about 0.75 mm.

  To obtain the plate of a device according to the invention, the plate 16 is cut with a press following the contours 3 'shown in phantom

in Figure 5.

  The plate 4 "obtained (FIG. 6) is of generally rectangular shape, with the tracer wire 2 ′ which is off-center, and more precisely located near the longitudinal edge that can be seen at the top in FIG. 6, a through hole of relatively large dimensions, here with a triangular outline, being arranged near the edge that can be seen on the right in FIG. 6. The width of the plate 4 "

  is about 54 mm and its length about 86 mm.

  It will be observed that the tracer wire 2 'being disposed away from the hole 7 ", it

  can extend over the entire length of the 4 "plate.

  We will now explain how to prepare the plate 16.

  We have on a sheet 17 (Figure 7) of plastic, for example white PVC 0.35 mm thick, a thin sheet 18 of plastic adhesive on both sides, then on the sheet 18 we have the wires plotters 2 'and above them a similar plastic sheet 19

on sheet 17.

  This assembly is then placed in a heating press which will keep these different elements intimately applied against each other, for example for 20 min at 120 C, so that the different

  constituents become intimately linked to each other.

  It will be observed that a small notch has been made in the plate 19 at the end of its edge which we see on the left in FIG. 5, for each of the

  2 'wires, so that they have an end section located outside.

  This in particular makes it easier to identify when cutting along the contours 3 '(the plates 17 and 19 being opaque, the tracer wires 2' do not

  are not visible in the thickness of this plate).

  In a variant not shown, the sheets 17 to 19 are replaced by two sheets adhesive-coated on one side which sandwich the wires 2 ′, the assembly between these sheets and the tracer wires being effected by passage between heating rollers; and in another variant not illustrated, it is in a similar way that a strip similar to the

band 1.

  Many other variants are possible depending on the circumstances, the plate being able to be fixed by other means to the object to be protected; and / or possibly having another shape, for example round, it being understood that the plate remains flat and thin and that it comprises at least one part whose width, measured transversely to the tracer wire 2, remains relatively large, that is to say that is, it remains at least 1 cm; and or

  obtainable by molding with inclusion of the tracer wire.

  More generally, it is recalled that the invention is not limited to

example described and represented.

Claims (12)

  1. Device recognizable by an anti-theft barrier, characterized in that it comprises a plate (4; 4 '; 4 ") of flat and thin plastic material in which is embedded a tracer wire (2; 2') detectable electro-magnetically by said barrier, said monobloc plate (4; 4 '; 4 ") having at least one part (5; 5') whose width, measured transversely to said tracer wire (2), is greater than 1 cm.   2. Device according to claim 1, characterized in that it   comprises a marking label (8) affixed to said plate (4).   3. Device according to claim 1, characterized in that it   has marking signs (9 ') written directly on the plate (4').   4. Device according to any one of claims 1 to 3,   characterized in that it has a hole (7; 7 '; 7 ") for passage of a fixing means (11; 1 1') to an article (10) to be protected against theft. 5. Device according to claim 4, characterized in that said   plate has two said through holes (7 '), arranged side by side.   6. Device according to any one of claims 1 to 5,   characterized in that said plate comprises a part (5; 5 ') of generally rectangular shape to which is attached a tab (6; 6') projecting in which is made at least one hole (7; 7 ') for passage of 'a means of attachment (11; 11') to an article (10) to be protected against theft.   7. Device according to any one of claims 1 to 4,   characterized in that said plate (4 ") is generally rectangular in shape and   in that it has a hole (7 ") away from said tracer wire (2 ').   8. Method for preparing a device according to any one   of claims 1 to 7, characterized in that it comprises the operation of   preparing an element (1; 16) of flat and thin plastic material in which said tracer wire (2; 2 ') is embedded, said element having a width, measured transversely to said tracer wire, greater than 1 cm; then the operation of   cut said plate (4; 4 '; 4 ") in said element (1; 16).   9. Method according to claim 8, characterized in that said operation of preparing an element (1) comprises the operation of extruding said plastic material.   10. Method according to claim 8, characterized in that said operation of preparing an element (4 ") comprises the operation of laminating two sheets (17, 19) made of said plastic material, between which said wire tracer (2 ') when sandwiched.   11. Method according to any one of claims 8 to 10,   characterized in that said element (16) has several said tracer wires (2 '),   arranged parallel to each other.   12. Method for preparing a device according to any one   of claims 1 to 7, characterized in that it comprises the operation of   preparing said plate by overmolding said tracer wire with said plastic material.