Acoustomagnetic Anti-theft label and bias wire element thereof

Abstract

The present application relates to the technical field of acoustomagnetic labels. Disclosed are an acoustomagnetic anti-theft label and a bias wire element thereof. The acoustomagnetic anti-theft label comprises a resonant-cavity upper housing, a resonant-cavity bottom cover, resonant members, a bias wire element and a double-sided adhesive layer, wherein the resonant members are disposed in a resonant cavity; the double-sided adhesive layer is adhered to the back side of the resonant-cavity bottom cover, the bias wire element is sandwiched between the resonant-cavity bottom cover and the double-sided adhesive layer, and a bonding face is provided on the side of the double-sided adhesive layer that faces away from the resonant-cavity bottom cover; the shape of the cross section of the bias wire element is flat, and the bias wire element is provided with a first surface, a second surface and two bent edges, each of the two bent edges being located on both the edge of the first surface and the edge of the second surface; and the first surface is attached to the resonant-cavity bottom cover, and the second surface is bonded to the double-sided adhesive layer. The design of flat wires overcomes the limitation of the total thickness of an acoustomagnetic label, and a large-diameter round wire can be flattened by means of pressing or stretching, so as to obtain a larger cross-sectional area, thereby improving the total magnetic flux of a bias wire element, and making the effective magnetic flux closer to that of resonant members, thus ensuring the frequency stability of the acoustomagnetic label.

Description

An acoustic magnetic anti-theft tag and its bias wire element Technical Field

[0001] The utility model relates to the technical field of acousto-magnetic labels, in particular to an acousto-magnetic anti-theft label and a biasing wire element thereof. Background Art

[0002] Currently, a common anti-theft technology used in supermarkets is acousto-magnetic tags, commonly known as "soft tags." These tags can be printed with a deceptive barcode or manufacturer logo on the front, with a self-adhesive sticker on the back. They contain a resonant chip and a biasing element, allowing them to be directly attached to merchandise for theft protection. When a thief takes unpaid merchandise out of the mall, the undemagnetized acousto-magnetic tag attached to the merchandise passes through the loss prevention door, triggering an alarm.

[0003] Existing acoustomagnetic anti-theft tags on the market use a structural design consisting of a box, a resonant sheet, a biasing element, and double-sided tape. One or more resonant sheets are stacked and placed in the box, and the biasing element provides a biasing magnetic field for the resonant sheets. Currently, all biasing elements on the market are made from cold-rolled alloy steel strips that are then longitudinally sheared (slitting) and cut. Existing biasing elements generally have a width of 3.0mm to 6.0mm and a thickness of 0.05mm to 0.10mm. These thin biasing elements require expensive 20-roll or 26-roll high-precision cold rolling mills and precision slitting machines to manufacture, resulting in very high processing costs. The magnetic anisotropy of the biasing element along its length is a key factor in ensuring the stable frequency and reliable activation and deactivation of acoustomagnetic tags in large quantities. Relatively speaking, the magnetic anisotropy of bias components made from wide-band rolled and then slit is not as good as that of bias wire components made from cold-drawn wire. Therefore, more expensive metals are needed to produce internal magnetocrystalline anisotropy or to precipitate a second phase after heat treatment, which also leads to the high cost of bias sheet components.

[0004] Prior art uses bias wire components made of round wire. This requires straightening before cutting, but after cutting, the wire tends to roll on the adhesive surface, making it difficult to ensure the bias wire is properly positioned. Furthermore, the thickness of security tags (typically 1.5mm to 2.0mm) limits the diameter of the round wire, thus limiting further increases in total magnetic flux.

[0005] In summary, existing bias sheet components are expensive to manufacture and their magnetic anisotropy is inferior to that of bias wire components. Furthermore, the small-diameter bias wire components have low total magnetic flux, making it difficult to maintain frequency stability in acoustomagnetic anti-theft tags.

[0006] Utility Model Content

[0007] The technical problem to be solved by the present invention is that the processing cost of the existing bias sheet element is high, the magnetic anisotropy is not as good as that of the bias round wire element, and at the same time, the total magnetic flux of the small diameter bias round wire element is low, making it difficult to ensure the frequency stability of the acoustomagnetic anti-theft tag.

[0008] In order to solve the above technical problems, the utility model provides an acoustic magnetic anti-theft tag:

[0009] The acousto-magnetic anti-theft tag includes a resonant cavity upper shell, a resonant cavity bottom cover, a resonant plate, a bias wire element, and a double-sided adhesive layer. The resonant cavity upper shell is fixedly connected to the resonant cavity bottom cover. The interior of the resonant cavity upper shell forms a resonant cavity, and the resonant plate is arranged in the resonant cavity.

[0010] The double-sided adhesive layer is adhered to the side of the resonance cavity bottom cover facing away from the resonance cavity upper shell, the biasing wire element is sandwiched between the resonance cavity bottom cover and the double-sided adhesive layer, and the double-sided adhesive layer is provided with an adhesive surface on the side facing away from the resonance cavity bottom cover;

[0011] The cross-section of the bias wire element is flat, and has a first plane, a second plane, and two curved edges. The angle between the first plane and the second plane is between -20° and 20°, and the two curved edges are located at the edges of the first plane and the second plane.

[0012] The first plane is in contact with the bottom cover of the resonant cavity, the second plane is adhered to the double-sided adhesive layer, and the cross-sectional area of ​​the bias wire element is 0.03mm 2 ~7.1mm 2 Any value in between.

[0013] Furthermore, the cross-sectional area of ​​the bias wire element is 0.15 mm 2 ~2.0mm 2 Any value in between.

[0014] Furthermore, the thickness of the biasing wire element is equal to the maximum distance between the first plane and the second plane, and the thickness of the biasing wire element is any size between 0.11 mm and 0.80 mm.

[0015] Furthermore, the thickness of the biasing wire element is equal to the maximum distance between the first plane and the second plane, and the thickness of the biasing wire element is any size between 0.20 mm and 0.60 mm.

[0016] Furthermore, the length of the biasing wire element is any size between 20 mm and 45 mm.

[0017] Furthermore, the length of the biasing wire element is any size between 22 mm and 35 mm.

[0018] Furthermore, at least two resonance plates are provided, and at least two resonance plates are arranged in a stacked manner in the height direction of the resonance cavity.

[0019] Furthermore, the first plane and the bottom cover of the resonance cavity are bonded together by double-sided tape or glue.

[0020] Furthermore, the adhesive surface of the double-sided adhesive layer is also provided with a separation backing paper.

[0021] In order to solve the above technical problems, the utility model provides a bias wire element of an acousto-magnetic anti-theft tag:

[0022] The cross-section of the bias wire element is flat, and has a first plane, a second plane, and two bent edges. The angle between the first plane and the second plane is between -20° and 20°, and the two bent edges are located at the edges of the first plane and the second plane.

[0023] The first plane is used to fit with the bottom cover of the resonance cavity of the acousto-magnetic anti-theft label, and the second plane is adhered to the double-sided adhesive layer of the acousto-magnetic anti-theft label. The cross-sectional area of ​​the bias wire element is 0.03mm 2 ~7.1mm 2 Any value in between.

[0024] Compared with the prior art, the acoustomagnetic anti-theft tag and its bias wire element of the present invention have the following beneficial effects: the acoustomagnetic anti-theft tag adopts a design form of a resonance cavity upper shell, a resonance cavity bottom cover, a resonance plate, a bias wire element and a double-sided adhesive layer. The resonance cavity upper shell is fixedly connected to the resonance cavity bottom cover and forms a resonance cavity inside, and the resonance plate is arranged in the resonance cavity. The resonance plate enclosed in the resonance cavity has good stability, and the resonance plate is reliably protected by the resonance cavity upper shell. Moreover, the bias wire element is sandwiched between the resonance cavity bottom cover and the double-sided adhesive layer, and the bias wire element is bonded and fixed to the back of the resonance cavity bottom cover by the double-sided adhesive layer. The double-sided adhesive layer is provided with an adhesive surface on the side of the double-sided adhesive layer facing away from the resonance cavity bottom cover, and the acoustomagnetic anti-theft tag can be bonded and fixed to the commodity by the adhesive surface.

[0025] The cross-sectional shape of the bias wire element is flat, which has better magnetic anisotropy than the existing bias sheet element and lower processing cost. It has a first plane, a second plane and two bent edges. The cross-sectional area of ​​the bias wire element is 0.03mm. 2 ~7.1mm 2 It should be noted that the bias wire element can be made of a wire material with a roughly circular cross-section by flattening or cold drawing. While reducing the thickness of the larger diameter round wire, a larger cross-sectional area can be obtained, thereby increasing the total magnetic flux of the bias wire element and ensuring the frequency stability of the acousto-magnetic anti-theft tag.

[0026] Furthermore, flattened or cold-drawn flat wires exhibit excellent straightness, eliminating the need for specialized straightening processes typically required for round wires. Furthermore, the included angle between the first and second planes of the offset wire element ranges from -20° to 20°, preventing rolling during cutting. This reduces the difficulty of offset wire processing and enhances the fit between the offset wire element and the resonant cavity bottom cover and the double-sided adhesive layer, making it suitable for high-volume lamination processing. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] FIG1 is a schematic cross-sectional exploded view of an acousto-magnetic anti-theft tag according to an embodiment of the present invention;

[0028] FIG2 is an enlarged perspective view of the biasing wire element in an embodiment of the present invention;

[0029] In the figure, 1-resonance cavity upper shell, 10-resonance cavity, 2-resonance cavity bottom cover, 3-resonance plate, 4-bias wire element, 41-first plane, 42-second plane, 43-bent edge, 5-double-sided adhesive layer, 50-adhesive surface, 6-separation bottom paper. DETAILED DESCRIPTION

[0030] The following embodiments are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0031] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like used in the present invention to indicate orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0032] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature specified as "first" or "second" may explicitly or implicitly include one or more of such features. In the description of this utility model, "plurality" means two or more, unless otherwise specifically defined.

[0033] In this utility model, unless otherwise specified or limited, the terms "installed," "connected," "connect," "fixed," etc. should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; they can refer to direct connection or indirect connection through an intermediate medium; they can refer to internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in this utility model based on specific circumstances.

[0034] As shown in Figure 1, an acoustic magnetic anti-theft tag of an embodiment of the present invention includes a resonance cavity upper shell 1, a resonance cavity bottom cover 2, a resonance plate 3, a bias wire element 4 and a double-sided adhesive layer 5. The resonance cavity upper shell 1 is fixedly connected to the resonance cavity bottom cover 2, and a resonance cavity 10 is formed inside the resonance cavity upper shell 1. The resonance plate 3 is arranged in the resonance cavity 10; the double-sided adhesive layer 5 is bonded to the side of the resonance cavity bottom cover 2 facing away from the resonance cavity upper shell 1, and the bias wire element 4 is sandwiched between the resonance cavity bottom cover 2 and the double-sided adhesive layer 5. The double-sided adhesive layer 5 has an adhesive surface 50 on the side facing away from the resonance cavity bottom cover 2.

[0035] As shown in FIG2 , the cross-sectional shape of the bias wire element 4 is flat, and it has a first plane 41, a second plane 42, and two bent edges 43. The angle between the first plane 41 and the second plane 42 is between -20° and 20°, and the two bent edges 43 are both located at the edges of the first plane 41 and the second plane 42. The first plane 41 is in contact with the bottom cover 2 of the resonance cavity, and the second plane 42 is adhered to the double-sided adhesive layer 5. The cross-sectional area of ​​the bias wire element 4 is 0.03 mm. 2 ~7.1mm 2 Any value in between.

[0036] The acousto-magnetic anti-theft tag adopts a design form of a resonance cavity upper shell 1, a resonance cavity bottom cover 2, a resonance plate 3, a bias wire element 4, and a double-sided adhesive layer 5. The resonance cavity upper shell 1 is fixedly connected to the resonance cavity bottom cover 2 and forms a resonance cavity 10 inside. The resonance plate 3 is arranged in the resonance cavity 10. The resonance plate 3 enclosed in the resonance cavity 10 has good stability, and the resonance cavity upper shell 1 provides reliable protection for the resonance plate 3. In addition, the bias wire element 4 is sandwiched between the resonance cavity bottom cover 2 and the double-sided adhesive layer 5. The bias wire element 4 is bonded and fixed to the back of the resonance cavity bottom cover 2 by the double-sided adhesive layer 5. The double-sided adhesive layer 5 has an adhesive surface 50 on the side facing away from the resonance cavity bottom cover 2. The adhesive surface 50 can be used to bond and fix the acousto-magnetic anti-theft tag to the commodity.

[0037] The bias wire element 4 has a flat cross-sectional shape, which has better magnetic anisotropy than the existing bias sheet element and has a low processing cost. It has a first plane 41, a second plane 42 and two bent edges 43. The cross-sectional area of ​​the bias wire element 4 is 0.03 mm. 2 ~7.1mm2 It should be noted that the bias wire element 4 can be made of a wire material with a roughly circular cross-section by flattening or cold drawing. While reducing the thickness of the larger diameter round wire, a larger cross-sectional area can be obtained, thereby increasing the total magnetic flux of the bias wire element 4 and ensuring the frequency stability of the acousto-magnetic anti-theft tag.

[0038] Furthermore, the flattened or cold-drawn flat wire has excellent straightness, eliminating the need for the specialized straightening process typically required for round wire. Furthermore, the included angle between the first plane 41 and the second plane 42 of the bias wire element 4 is between -20° and 20°. These two planes prevent rolling, making the flat wire less susceptible to rolling displacement during cutting. This reduces the difficulty of processing the bias wire element 4 and improves the fit between the resonant cavity bottom cover 2 and the double-sided adhesive layer 5, making it suitable for large-scale bonding processing.

[0039] Preferably, the cross-sectional area of ​​the bias wire element 4 is 0.15 mm 2 ~2.0mm 2 In addition, the thickness H of the biasing wire element 4 is equal to the maximum distance between the first plane 41 and the second plane 42, and the thickness H of the biasing wire element 4 is any size between 0.11 mm and 0.80 mm. Preferably, the thickness of the biasing wire element 4 is any size between 0.20 mm and 0.60 mm. The length of the biasing wire element 4 is any size between 20 mm and 45 mm. Preferably, the length of the biasing wire element 4 is any size between 22 mm and 35 mm.

[0040] In this embodiment, the bias wire element 4 can be made of a round wire with a diameter of 0.2 mm, which is flattened or stretched to a thickness of 0.11 mm and has a cross-sectional area of ​​about 0.03 mm. 2 Furthermore, the length of the bias wire element 4 is 45 mm, and it is equipped with two resonance plates 3. The resonant frequency of the tag is 58.8 kHz. In order to meet different usage requirements, in other embodiments, the bias wire element can be made of 0.5 mm round wire, which is flattened or stretched to a thickness of 0.20 mm, and its cross-sectional area is about 0.2 mm. 2 Moreover, the length of the bias wire element 4 is 35 mm, and it is equipped with six resonance pieces. The resonance frequency of the tag is 58.1 kHz.

[0041] Alternatively, the bias wire element may be a 3 mm diameter round wire that has been flattened or stretched to a thickness of 0.80 mm, giving a cross-sectional area of ​​approximately 7.1 mm. 2 ; In addition, the length of the bias wire element 4 is 20 mm, and it is equipped with three resonance pieces. The resonant frequency of the tag is 57.5 kHz.

[0042] In addition, at least two resonant plates 3 are provided, and at least two resonant plates 3 are stacked and arranged in the height direction of the resonant cavity 10 to provide better acoustomagnetic performance. The first plane 41 is bonded to the resonant cavity bottom cover 2 via double-sided tape or glue, further enhancing the secure connection between the bias wire element 4 and the resonant cavity bottom cover 2. The adhesive surface 50 of the double-sided adhesive layer 5 is also provided with a release paper 6. Before use, the release paper 6 is attached to the adhesive surface 50 of the double-sided adhesive layer 5 to ensure that the adhesive surface 50 does not become contaminated and lose its adhesive strength. During use, the release paper 6 is removed to affix the acoustomagnetic anti-theft label to the product.

[0043] The bias wire element of an acoustomagnetic anti-theft tag according to an embodiment of the present invention is shown in FIG1 . The cross-sectional shape of the bias wire element 4 is flat, and it has a first plane 41, a second plane 42 and two bent edges 43. The angle between the first plane 41 and the second plane 42 is between -20° and 20°. The two bent edges 43 are both located at the edges of the first plane 41 and the second plane 42. The first plane 41 is used to fit with the resonant cavity bottom cover 2 of the acoustomagnetic anti-theft tag, and the second plane 42 is adhered to the double-sided adhesive layer 5 of the acoustomagnetic anti-theft tag. The cross-sectional area of ​​the bias wire element 4 is 0.03 mm. 2 ~7.1mm 2 Any value between , suitable for mass-production lamination processing.

[0044] Compared with the existing biasing piece element, the magnetic anisotropy is good and the processing cost of the biasing wire element 4 is low. It has a first plane 41, a second plane 42 and two bent edges 43. The cross-sectional area of ​​the biasing wire element 4 is 0.03mm 2 ~7.1mm 2 It should be noted that the bias wire element 4 can be made of a wire material with a roughly circular cross-section by flattening or cold drawing. While reducing the thickness of the larger diameter round wire, a larger cross-sectional area can be obtained, thereby increasing the total magnetic flux of the bias wire element 4 and ensuring the frequency stability of the acousto-magnetic anti-theft tag.

[0045] Furthermore, the flattened or cold-drawn flat wire has excellent straightness, eliminating the need for the specialized straightening process typically required for round wire. Furthermore, the included angle between the first plane 41 and the second plane 42 of the bias wire element 4 is between -20° and 20°, preventing rolling during cutting. This reduces the difficulty of processing the bias wire element 4 and improves the fit between the bottom cover 2 of the resonant cavity and the double-sided adhesive layer 5.

[0046] In this embodiment, the bias wire element 4 can be made of a round wire with a diameter of 0.2 mm, which is flattened or stretched to a thickness of 0.11 mm and has a cross-sectional area of ​​about 0.03 mm. 2Furthermore, the bias wire element 4 is 45 mm long and equipped with two resonance plates. The resonant frequency of the tag is 58.8 kHz. In order to meet different usage requirements, in other embodiments, the bias wire element can be a round wire with a diameter of 0.50 mm, which is flattened or stretched to a thickness of 0.20 mm and has a cross-sectional area of ​​about 0.2 mm. 2 ; In addition, the length of the bias wire element 4 is 35 mm, and it is equipped with six resonance pieces. The resonant frequency of the tag is 58.1 kHz.

[0047] Alternatively, the bias wire element may be a 3 mm round wire that has been flattened or stretched to a thickness of 0.80 mm, giving a cross-sectional area of ​​approximately 7.1 mm. 2 ; In addition, the length of the bias wire element 4 is 20 mm, and it is equipped with three resonance pieces. The resonant frequency of the tag is 57.5 kHz.

[0048] In addition, in other embodiments, a combination of at least one bias wire element and bias wires or bias plates of other shapes may be used; the first plane and the second plane are arranged in parallel, or the angle between the first plane and the second plane is -20°, -15°, -10°, -5°, 5°, 10°, 15°, 20° and any angle between -20° and 20°. The above implementation modes all fall within the protection scope of the present utility model.

[0049] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and replacements can be made without departing from the technical principles of the present invention. These improvements and replacements should also be regarded as the scope of protection of the present invention.

Claims

1. An acoustic-magnetic anti-theft label, characterized in that, It includes an upper shell of the resonant cavity, a bottom cover of the resonant cavity, a resonant sheet, a bias wire element and a double-sided adhesive layer. The upper shell of the resonant cavity is fixedly connected to the bottom cover of the resonant cavity. A resonant cavity is formed inside the upper shell of the resonant cavity, and the resonant sheet is arranged in the resonant cavity; The double-sided adhesive layer is bonded to the side of the bottom cover of the resonant cavity facing away from the upper shell of the resonant cavity. The bias wire element is clamped between the bottom cover of the resonant cavity and the double-sided adhesive layer. A bonding surface is provided on the side of the double-sided adhesive layer facing away from the bottom cover of the resonant cavity; The cross-sectional shape of the bias wire element is flat, and it has a first plane, a second plane and two bent edges. The angle between the first plane and the second plane is between -20° and 20°, and both of the two bent edges are located at the edges of the first plane and the second plane; The first plane is in contact with the bottom cover of the resonance cavity, the second plane is adhered to the double-sided adhesive layer, and the cross-sectional area of ​​the bias wire element is 0.03mm 2 ~7.1mm 2 Any value in between.

2. The acousto-magnetic anti-theft label according to claim 1, characterized in that, The cross-sectional area of the offset wire element is 0.15 mm 2 to 2.0 mm 2 any value therebetween.

3. The acousto-magnetic anti-theft label according to claim 2, characterized in that, The thickness of the bias wire element is equal to the maximum distance between the first plane and the second plane, and the thickness of the bias wire element is any size between 0.11 mm and 0.80 mm.

4. The acousto-magnetic anti-theft label according to claim 2, characterized in that, The thickness of the bias wire element is equal to the maximum distance between the first plane and the second plane, and the thickness of the bias wire element is any size between 0.20 mm and 0.60 mm.

5. The acousto-magnetic anti-theft label according to claim 1, characterized in that, The length of the bias wire element is any size between 20 mm and 45 mm.

6. The acousto-magnetic anti-theft label according to claim 1, characterized in that, The length of the bias wire element is any size between 22 mm and 35 mm.

7. The acousto-magnetic anti-theft label according to claim 2, characterized in that, At least two resonant sheets are provided, and at least two resonant sheets are arranged in a stacked manner in the height direction of the resonant cavity.

8. The acousto-magnetic anti-theft label according to claim 2, characterized in that, The first plane is adhesively connected to the bottom cover of the resonant cavity through double-sided adhesive or glue.

9. The acousto-magnetic anti-theft label according to claim 1, characterized in that, A release base paper is further provided on the bonding surface of the double-sided adhesive layer.

10. A bias wire element of an acousto-magnetic anti-theft label, characterized in that, The cross-sectional shape of the bias wire element is flat, and it has a first plane, a second plane and two bent edges. The angle between the first plane and the second plane is between -20° and 20°, and both of the two bent edges are located at the edges of the first plane and the second plane; The first plane is used to fit with the bottom cover of the resonant cavity of the acousto-magnetic anti-theft label, the second plane is adhered to the double-sided adhesive layer of the acousto-magnetic anti-theft label, and the cross-sectional area of the bias wire element is 0.03 mm 2 to 7.1 mm 2 for any value therebetween.

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