JPS63200297A - Electric resonance tag for preventing shop lift - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention broadly relates to electrical resonant circuits,
In particular, this invention is applied to prevent shoplifting and relates to an electrically resonant tag that is made into an inexpensive tag.

In particular, the present invention relates to an electric resonant tag for preventing shoplifting, which is compact but has greatly increased sensitivity by widening the space inside the coil.

(Prior Art) Electrical resonance tags are widely used in supermarkets, libraries, department stores, and other stores to prevent shoplifting. In that case, the electrical resonant tags used for shoplifting prevention, such as those used on cheap products in supermarkets, are made of aluminum film laminated to an insulating film to make them extremely cheap, since the products themselves are cheap and the tags are disposable. Etched to form an electrical resonant circuit is widely used.

Since the sensitivity is not good, the coil is designed to be large in order to increase the sensitivity. Therefore, in order to prevent the tag from becoming too large, the space inside the coil 10 is used to install a capacitor 20 therein, as in the embodiment shown in the plan view shown in FIGS. 3 and 4. Some or all of the coils were formed, or the coils were wound to the very limit inside the coil.

That is, conventionally, the overall size of the tag has been reduced by narrowing the space inside the coil.

(The problem that the invention was trying to solve) However, upon careful study of this, it was found through various experiments that the space inside the coil has a great effect on its sensitivity.

That means in the same space as before.

Attempts were made to increase the sensitivity by increasing the overall size of the coil and the number of turns, but in this case the space inside the coil had to be sacrificed. Therefore, this resulted in a decrease in sensitivity, and in addition, the improvement in sensitivity was not so great.

Once you understand this, it is so obvious. However, in the past, in this field, the question was whether the highest sensitivity could be obtained by making the river larger in the same space, that is, by making the coil itself larger or the space inside it larger. It had not been studied. Therefore, the space inside the coil is only recognized as a mere space, and various designs have been made to effectively utilize this wasted space.

Therefore, they did not realize that this space was less than a quarter of the total area of the coil, and that the sensitivity could not be increased sufficiently.

(Means for Solving the Problems) In view of the above nine problems, the electrical resonance tag for preventing shoplifting according to the present invention has increased its sensitivity by maximizing the space inside its coil. It is.

The specific structure of the electrical resonance tag for shoplifting prevention according to the present invention will be described in detail below.

First, there is the insulation sheet. There are capacitors formed on the front and back sides of the corners of this insulating sheet. moreover,
Each wing of the capacitor has a coil connected at both ends. This coil.

It is structured as follows.

First, the ratio of the total area of the coil including the space inside this coil to the area of the space inside this coil is 3:1 to 4.
It is against 3. and.

This coil has a shape in which the above-mentioned capacitor portion is rounded.

(Function) Since the electrical resonance tag for preventing shoplifting in the first system of the present invention is configured as above 9, the following effects have arisen.

First, an electrical resonant circuit is formed by a capacitor formed on the front and back sides of the corner of an insulating sheet and a coil whose both ends are connected to each ridge of the capacitor. Here, since this coil has a shape in which the above-mentioned portion 4 is rounded, the capacitor is provided in this portion.

The ratio of the total area of the coil including the space inside the coil to the area of the space inside the coil is from 3:1 to 4:3. Therefore, this coil has a very large internal space to obtain maximum sensitivity.

(Example) The electric resonant tag for shoplifting prevention according to the present invention will be described in detail using one embodiment thereof, together with the accompanying drawings showing the same.

FIG. 1 shows an embodiment of an electric resonant tag for preventing shoplifting according to the present invention, and FIG. 1a is a surface view of the tag;
Figure 1 shows its back view.

First, there is an insulating sheet 30. And capacitor 2
There is 0. This capacitor 20 is formed on the front and back sides of the corners of the above-mentioned insulating sheet. Finally, there is the coil lO. This coil 10 has both ends 1
1.12 is connected to each type 21.22 of the capacitor 20 described above.

Note that this coil 10 jumps over the above-mentioned insulating sheet 30 near its inner terminal. At this jump point, the coil 10 is electrically conductive at its junction points 13 and 14. However.

This continuity can be achieved by various methods, such as breaking this part of the insulating sheet 30 mechanically or by heating, or penetrating it with a conductive material, and any conventional technique may be used.

This coil IO is constructed as follows. First, the total area of the coil including the space 15 inside this coil 10 and the space 15 inside this coil IO
The area ratio of is from 3:1 to 4:3. This coil 10 has a shape in which the portion of the capacitor 20 described above is rounded. Furthermore, this coil 10
The size is from 30mm x 35mm to 60mm x 80m
The range is up to m.

By the way, two typical examples will be explained. The first is the capacitor 20 mentioned above.

They are a pair. This is shown in Figure 1,
The size of the capacitor 20 is 15 mm and 15 mm, respectively.
and a right triangle with sides of 20 mm.

So, the size of the coil 10 is = 60mm x 50m
The capacitor 20 has a rectangular shape with a rounded corner. And there are 7 coils divided into +8++ut+ coil width. The sensitivity of this electrically resonant tag has been significantly increased by 30 to 35% compared to a tag of the same size.

FIG. 2 shows another embodiment of the electrical resonant tag for shoplifting prevention according to the present invention, in which FIG. 2a shows its front view and FIG. 2 shows its back view.

In the second embodiment, there are two pairs of capacitors 20. This is smaller than the first embodiment,
It was also developed with the aim of preventing a decrease in sensitivity due to miniaturization. The size of each capacitor 20 is 1
Two right triangles with sides of 4 mm, 14 mm, and 19 mm are used.

The size of the coil IO is 40 mm x 45 mm in circumference, and it is rectangular with the capacitor 200 section cut out in the shape of Mt. Fuji. And the coil width is +8mm divided into 7 pieces. The sensitivity of this resonant tag is 25% higher than that of a tag of the same size, which is also a significant increase.

In both the first and second embodiments, the insulating sheet is 261. A polyethylene film with a thickness of t nl was used. The thickness of the aluminum film is 971m for the capacitor and 30-50μm for the coil.
Generally, 35 μm is used.

Although it is conceivable to provide the capacitors 20 at the four corners of the insulating sheet 30, the sensitivity will not be particularly improved compared to the second embodiment. Further, the practical size of this black tag is in the range of 30 mm x 35 mm to 60 am x 80 mm, but the size may vary depending on the product used and the parent device of the tag. moreover,
The above coil lO and capacitor 20 are connected to an insulating sheet 30
This is an etched version of the aluminum film laminated to the

(Effects of the Invention) Since the electrical resonance tag for shoplifting prevention according to the present invention has a configuration of 9 or more tags, its sensitivity is significantly improved compared to a tag of the same size.

[Brief explanation of the drawing]

FIG. 1 shows an embodiment of an electric resonant tag for preventing shoplifting according to the present invention, and FIG. 1a is a surface view of the tag;
Figure 1 shows its back view. FIG. 2 shows another embodiment. Figure 2a shows its front view, and Figure 2a shows its back view. FIG. 3 is a plan view showing one embodiment of a conventional shoplifting prevention electrical resonant tag. FIG. 4 shows a plan view showing another embodiment. 10... Coil 15... Space 20...
capacitor

Claims (6)

[Claims] (1) An insulating sheet, a capacitor formed on the front and back sides of the corners of the insulating sheet, and a coil having both ends connected to each pole of the capacitor, and configured as follows. a The ratio of the total area of the coil including the space inside the coil to the area of the space inside this coil is from 3:1 to 4:3. b The coil must have a shape with the above-mentioned capacitor section rounded. (2) The electrical resonance tag for preventing shoplifting according to claim 1, wherein the capacitor is a pair. (3) The electrical resonance tag for preventing shoplifting according to claim 1, characterized in that the capacitors are two pairs. (4) Coil size is from 30mm x 35mm to 60mm
The electric resonant tag for shoplifting prevention according to claim 1, having a size up to 80 mm x 80 mm, with the capacitor portion having a rounded corner. (5) Coil size is from 40mm x 45mm to 50mm
5. The electrical resonant tag for shoplifting prevention according to claim 4, wherein the capacitor portion has a shape with rounded corners in the range of up to 60 mm x 60 mm. (6) The electrical resonance tag for preventing shoplifting according to claim 1, wherein the coil and the capacitor are etched from an aluminum film laminated to an insulating sheet.