JP2001006061A - Power source circuit for radio tag - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a circuit where a battery is used for a long time by supplying the DC output of the battery as the circuit power source of each circuit in a radio tag by means of energizing a radio wave reception time switching element. SOLUTION: Radio wave received by the resonance circuit 2 of a radio tag receiving circuit part 1 is rectified between the base and emitter of a transistor 4 and the switching of the transistor 4 is started. Then the transistor 5 is also switched by the switching of the transistor 11 and the power source is supplied to processing logic or an amplifier circuit 6 in a receiving circuit from the battery 3 with a power source line 7. In this case, the potential of the transistor 4 is kept in L level by a delay capacitor C2 and, besides, FET 1 is arranged for discharging an electric charge remaining in the power source line 7 after turning off the transistor 5 since electric wave is not received.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wireless tag fixed to a product to prevent shoplifting in a CD shop or the like, and an article monitoring apparatus using the same.
In particular, the present invention relates to a power supply circuit having a long life when a wireless tag capable of identifying the type of an individual product or a product number is used.

[0002]

2. Description of the Related Art Heretofore, there has been known a non-contact type wireless tag system in which a wireless tag or a wireless card capable of managing an ID is attached to a product or article to perform distribution management and journalizing. For example, JP-A-11-59040, JP-A-10-203059
An example is shown in the official gazette.

[0003] However, the wireless tag has a wide application field because it can automatically recognize a person or an object without contact and without a power source. However, since a radio wave input is used as a power source, an electromagnetic coupling type 2 cm to 3 cm is used.
m, which is 10 cm to 20 cm, which is an electromagnetic induction type, and its reach is short. In order to recognize the tag, the tag must be brought close to the detector. Therefore, when trying to use the wireless tag in an article monitoring system that detects an anti-theft gate placed at a store entrance, there is a disadvantage that the reach distance is too short to be used.

[0004] In addition, there is a similar device using a microwave, but this device has a drawback that it is regulated by the Radio Law and is susceptible to ambient noise. 2 to 4 show the outline of the wireless tag. In FIG. 2, when a read signal is transmitted from the reader 21 from the antenna 22, the wireless tag 23 operates by receiving the signal and transmits its own information. The reader 21 receives the signal and sends it to the computer. The computer identifies the wireless tag from the information. Also,
The memory of the wireless tag is rewritten as needed by a writer integrated with the reader.

As shown in FIG. 3, the power supply of the above-mentioned conventional wireless tag uses an induced power generated by a magnetic field line generated from a transmitting antenna coil linked to a coil on the tag side. As the conventional wireless tags, there are a card type and a button type as shown in FIG.

The wireless tag is a new product that is an extension of a conventional barcode or two-dimensional barcode, and has the characteristics shown in Table 1, and has an advantage that the information amount is larger than that of a barcode. .

[0007]

[Table 1]

On the other hand, a passive paper tag which does not have a power supply therein is conventionally known as an article monitoring apparatus for preventing shoplifting of goods in a CD shop or the like.
This paper tag is attached to the product, and if you try to take out the product without permission, it will react when you pass the side of the transmitting device installed at the entrance of the store etc., and the alarm provided on the transmitting device will sound and the theft will be stolen Prevention.

[0009] However, although this paper tag is inexpensive, the alarm sounds at the gate, so if multiple people pass at the same time, it is not possible to know which person is trying to illegally take out the product, so that the site There is a drawback that is difficult to hold down. In addition, there is also a disadvantage that a criminal trying to forcibly pass through the gate cannot determine the point at which a warning is to be transmitted, so that he can escape with a delay.

[0010] Further, as a solution to this disadvantage, there is known a self-sounding type article monitoring apparatus which has a power supply inside, receives radio waves from a transmitter at an entrance, and sounds an alarm on the tag itself.

This self-sounding article monitoring device, for example, in the case of a CD, as shown in Japanese Patent Application No. 10-269030, includes a transparent case (clear case) made of a synthetic resin, an alarm operation detection switch and a buzzer. (A cassette accommodating a compact disc). The operation of the buzzer is controlled by a wireless reception circuit and a detection switch, and sounds when the cassette does not exist in the clear case or when the self-sounding article monitoring device passes through the gate.

At a store, a cassette containing a CD is housed in a clear case of a self-sounding article monitoring device and displayed, and when a compact disc is sold to a customer, the clerk sets the buzzer so as not to sound. The customer removes the cassette from the clear case and hands the customer a compact disc in exchange for a fee. The self-sounding article monitoring device from which the cassette has been taken out is repeatedly used.

In the above-mentioned self-sounding article monitoring apparatus, when the customer takes out the cassette from the clear case of the self-sounding article monitoring apparatus, the alarm operation detecting switch detects that no cassette is present in the clear case and outputs a buzzer. The buzzer sounds in response to the sounding command. This allows the clerk to know that the cassette has been illegally removed from the clear case.

If the customer attempts to take the cassette out of the store without permission while holding the cassette in the clear case of the self-sounding article monitoring device, the receiving circuit of the self-sounding article monitoring device is provided at the entrance gate or the like. A sounding command is issued to the buzzer in response to a signal from the circuit, and the buzzer sounds in response to the sounding command. This allows the clerk to know that the compact disc is being illegally taken out of the store.

A self-sounding article monitoring tag directly attached to an individual product has also been proposed by the same applicant.
(Japanese Patent Application No. 11-153113) The self-sounding tag has a boat shape with a length of 9 cm and a width of 2 cm, and the operating piece of the snap switch protruding from the case is pressed against the product and taped. Sticked to the product.

As long as the operation piece is pressed, the buzzer does not sound. However, if the tag is illegally removed from the product, the operation piece is turned on and the buzzer sounds. Also, if the user illegally silently tries to leave the entrance without unlocking, as described later, the buzzer sounds by receiving the radio wave of the oscillation device at the entrance.

However, these self-sounding article surveillance tags only sound an alarm when they are stolen, and cannot specify what kind of product is being taken out. In addition, if a tag for identifying an individual product can be attached to the product and used also as the anti-theft tag, it can be conveniently used as a POS input unit for ordinary inventory management and product delivery. However, as described above, the conventional wireless tag has a drawback that it cannot be used as a tag requiring a reach of at least several tens of cm because the usable range is limited in terms of distance.

[0018]

An object of the present invention is to provide a wireless tag for automatically identifying an article in a non-contact manner by incorporating a battery so that it can be detected within a range of several tens of cm, and using the battery for a long life. It is an object of the present invention to provide a wireless tag having a circuit capable of performing the following. Another object is to provide an article monitoring device using the wireless tag.

[0019]

A wireless tag according to the present invention comprises:
In a wireless tag attached to an article or the like and recognizing an ID in a non-contact manner, the wireless tag is provided with a tuning circuit that receives a radio wave transmitted from a transmitting device, and a switching element that is turned on by an output of the tuning circuit, When the radio wave is received, the DC output of the battery is supplied as the circuit power of each circuit of the wireless tag by the conduction of the switching element. Further, the frequency of the radio wave is several tens to several hundreds kHz.

The article monitoring apparatus of the present invention is a wireless tag attached to an article or the like and recognizing an ID in a non-contact manner. The wireless tag has a tuning circuit for receiving a radio wave transmitted from a transmitting apparatus. A switching element that is turned on by the output of the tuning circuit, and when the radio wave is received, the radio tag that supplies the DC output of the battery as a circuit power supply for each circuit of the radio tag by the conduction of the switching element is used when an abnormality occurs. It is characterized by issuing an alarm.

[0021]

Next, a power supply circuit of a wireless tag according to the present invention will be described. FIG. 1 is an explanatory diagram of a power supply circuit of a wireless tag according to the present invention. In FIG. 1, reference numeral 1 denotes a receiving circuit unit of the wireless tag. The wireless tag includes the receiving circuit unit 1, the transmitting circuit unit 11, and a demodulation circuit 8, a modulation circuit 10, and a processing logic 9 connected thereto.

The receiving circuit section 1 includes a resonance circuit 2 composed of L1 and C1, transistors 4 and 5, a signal amplification circuit 6, and a battery 3.
It is composed of The operation of the receiving circuit is as follows.

The radio wave received by the resonance circuit 2 is rectified between the base and the emitter of the transistor 4 (Tr2), and the transistor 4 starts switching. By switching of the transistor 4, a transistor 5 (Tr1)
Is also switched, and power is supplied from the battery 3 to the processing logic and the amplifier circuit 6 in the receiving circuit via the power supply line 7. At this time, the potential of the transistor 4 is kept at L level by the delay capacitor C2. Also FET1
Is provided to discharge the charge remaining in the power supply line 7 after the radio wave is no longer received and the transistor 5 is turned off.

When an experiment was conducted using the above-described receiving circuit for supplying power from the battery at the time of reception, the wireless tag was 90 c
m. Note that the example values of the antenna are L1 = 1.92 mH and C1 = 982 pF.
It is.

[0025]

As described above, the wireless tag using the power supply circuit of the present invention can greatly increase the receivable distance as compared with the conventional wireless tag without power supply. .

At the same time, by having the power supply circuit of the present invention, the battery life can be dramatically increased to 5 to 6 years since the battery is normally disconnected from the circuit. In addition, in the case of the conventional non-power-supply system, if the wireless tag is placed on the scanner for too long, the power supply becomes excessive, and the excess power is radiated through the heat radiation mechanism, causing the LSI itself to overheat and causing malfunction. Although there is a danger of shortening the service life, in the case of the wireless tag of the present invention, power is supplied by radio waves until the power supply line is turned on, and thereafter power is supplied from the battery. Therefore, there is an advantage that a heat radiating mechanism unlike the conventional one is not required.

[0027] In addition, since the radio wave receiving distance has been increased, the application range can be greatly expanded as compared with the conventional wireless tag, and it can be used for an article monitoring device, for example. By using this wireless tag for an article monitoring device, an article monitoring device that merely sounds an alarm can know the history of the product type and individual number, and can be applied to a POS terminal. , Its usability is greatly improved.

Also, if a member card is created using the wireless tag, for example, it is possible to know who and when and how often the member customer came to the store without entering the store just by entering the store. Market information such as what the member customer has purchased can be automatically obtained.

[Brief description of the drawings]

FIG. 1 is a receiving circuit diagram of a wireless tag of the present invention.

FIG. 2 is a diagram illustrating the principle of a wireless tag.

FIG. 3 is an explanatory diagram of power transmission of a wireless tag.

FIG. 4 is a diagram illustrating an example of a form of a wireless tag.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Receiving circuit 2 Tuning circuit 3 Battery 4 Transistor 5 Transistor 6 Amplifying circuit 7 Power supply line 8 Demodulation circuit 9 Processing logic 10 Modulation circuit

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H02J 17/00 G06K 19/00 K F term (Reference) 5B035 AA05 AA13 BB09 CA12 CA13 CA23 5B058 CA15 KA01 KA31 YA11 5C084 AA03 AA09 BB27 BB31 CC35 DD07 DD86 EE07 FF02 GG18 GG71 GG74 HH01 HH12 5G065 AA01 EA02 GA07 JA02 KA02 KA05 LA01 MA10

Claims (3)

[Claims] 1. A wireless tag attached to an article or the like and recognizing an ID in a non-contact manner, wherein the wireless tag has a tuning circuit for receiving a radio wave transmitted from a transmitting device, and a switching circuit which is turned on by an output of the tuning circuit. A wireless tag provided with an element, and supplies a DC output of a battery as a circuit power supply of each circuit of the wireless tag by conducting the switching element when the radio wave is received. 2. The wireless tag according to claim 1, wherein the frequency of the radio wave is several tens to several hundreds kHz. 3. A wireless tag attached to an article or the like and recognizing an ID in a non-contact manner. The wireless tag has a tuning circuit for receiving a radio wave transmitted from a transmitting device, and is turned on by an output of the tuning circuit. An article for providing an alarm at the time of abnormality by the wireless tag that supplies a DC output of a battery as a circuit power supply of each circuit of the wireless tag by conducting the switching element when the radio wave is received. Monitoring device.