JP3672727B2 - Antenna device for non-contact automatic ticket gate - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an antenna device, and is particularly suitable for a non-contact type automatic ticket gate for performing entrance / exit processing by exchanging data with a non-contact type card composed of an IC card having a wireless communication function. The present invention relates to an antenna device.
[0002]
[Prior art]
Conventionally, an antenna device provided in this type of contactless automatic ticket gate has an antenna portion on the upper surface of the casing on the entrance side of the ticket gate, and a user inserts a contactless card into the antenna portion. It is configured so that it can be held over.
[0003]
The antenna section is formed by a transmission loop coil and a reception loop coil wound in parallel on the upper surface of the housing. The transmitter loop coil is supplied with power and data transmission signals from the transmitter to the contactless card, and the receiver loop coil receives signals received from the contactless card to the transmitter. It is configured to be entered.
[0004]
[Problems to be solved by the invention]
Since the conventional antenna device transmits a signal for driving the contactless card from the transmission loop coil, the antenna device is incorporated when the contactless card cannot receive the signal. There is a problem that data cannot be exchanged between a processing machine such as a non-contact type automatic ticket gate and a non-contact type card. Therefore, the antenna device is desired to have a wide communication area that can communicate with the contactless card (see communication area (1) in FIG. 3 used in the description of the embodiment of the present invention).
[0005]
In order to expand the communication area described above, it is conceivable to increase the power supplied to the transmission loop coil. However, if the supplied power is increased, not only does it fall under the weak radio station specified in the Radio Law, but there is a concern that it may adversely affect other electronic devices. Therefore, it is desired to enlarge the communication area as much as possible below a predetermined supply power.
[0006]
By the way, when the loop coil is used as an antenna, the directivity in the axial direction of the loop coil (this publication), as clarified in page 54 of the publication “New Antenna Engineering” published on April 9, 1996. Then, it is known that the directivity of the E plane is the lowest at the axial center portion of the loop coil (see the vertical axis in FIG. 6 used in the embodiment of the present invention described later). Therefore, when the loop coil is employed in the antenna section of the non-contact automatic ticket gate, there is a risk that data transfer will be disturbed unless the non-contact card is placed as close as possible to the upper surface of the housing. For this reason, even if it is away from the upper surface of the housing, that is, it has a certain communication distance, the appearance of an antenna device capable of communication has been awaited.
[0007]
Further, when an antenna composed of a loop coil is installed close to a metal body, the resonance frequency is shifted due to the magnetic permeability of the metal body, so that there is a drawback that readjustment is required depending on the installation location.
[0008]
For example, when the loop coil is used as the antenna part of a non-contact type automatic ticket gate, the non-contact type automatic ticket gate includes a lot of metal parts and the like. There was the disadvantage that it had to be readjusted after the device was installed.
[0009]
Furthermore, the conventional loop coil type antenna device employs a configuration in which one resonance element is connected in series or in parallel to one transmission loop coil formed by being wound a plurality of times. Therefore, there is a drawback that the load of the power amplifier becomes heavy.
[0010]
Further, in the conventional antenna device, when an inrush current due to static electricity or the like is generated, there is a possibility that a circuit such as an amplifier circuit is destroyed. In particular, when the antenna device is used in a non-contact type automatic ticket gate, there are a wide variety of objects that are held over the antenna unit, and there is a high possibility that an inrush current will occur. Therefore, some protection means against the inrush current has been required. .
[0011]
Further, in the conventional loop coil type antenna device, in order to obtain a large radiated magnetic field strength at a predetermined frequency by the series resonance circuit, the number of loop coil windings (hereinafter sometimes referred to as “turns”) is increased. I had to. Therefore, since the inductance is increased, the capacitance has to be reduced, and there is a problem that a large amount of power cannot be supplied.
[0012]
Therefore, the present invention has been made to solve the above-described drawbacks, and its purpose is to increase the communication distance, eliminate the need for readjustment after installation, reduce the load of the power amplifier, and increase the inrush current. It is another object of the present invention to provide an antenna device that can be protected from the above and can supply a large amount of power.
[0013]
[Means for Solving the Problems]
In order to achieve the above object, an antenna device for a non-contact type automatic ticket gate according to claim 1 of the present invention provides a non-contact signal to a non-contact type card via an antenna composed of a plurality of loop coils wound. In the antenna device for a non-contact type automatic ticket gate that transmits a resonance element having a capacitor and a resistor connected in parallel for each turn of the loop coil wound in a plurality or a plurality of predetermined turns. provided Rutotomoni, of the plane of their loop coil wound multiple to the to the plane of the side to be held over the contactless card opposite with a predetermined spacing disposed a metal plate, further plurality An auxiliary metal plate is provided between the side surface of the wound loop coil and the metal plate .
[0014]
In order to achieve the above object, an antenna device for a non-contact type automatic ticket gate according to claim 2 of the present invention provides a non-contact signal to a non-contact type card via an antenna composed of a plurality of loop coils wound. the in non-contact antenna device for an automatic ticket gate for transmitting the plurality to any of a plurality of positions of the wound loop coil provided a resonant element connected to a capacitor and a resistor and in parallel Rutotomoni, the plurality Among the planes of the wound loop coils, a metal plate is disposed on the surface opposite to the side where the non-contact card is held, and a predetermined interval is provided, and further, the loop coils wound around the plurality of loop coils are arranged. An auxiliary metal plate is provided between the side surface and the metal plate .
[0015]
Non-contact antenna device for an automatic ticket gate machine according to claim 3 of the present invention, the surface opposite to the side where the loop coil is provided in the metallic plate, a transmitter for generating a signal to be supplied to the loop coils It is characterized in that is provided.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view when an antenna device A according to an embodiment is applied to a non-contact automatic ticket gate, and the ticket gate passage P is formed on the upper surface G ′ of the casing of the non-contact automatic ticket gate G. Is provided with an antenna part a for non-contact communication with the non-contact card C possessed by the user by wireless communication.
[0017]
In FIG. 1, S, S... Are photoelectric human detectors for detecting whether a user enters or exits the ticket gate passage P, or passes through the ticket gate passage P, and D opens and closes the ticket gate passage P. It is a door. T is a transmitter configured to exchange data with the contactless card C via the antenna part a. Reference numeral 100 denotes a controller, which is formed around the CPU, and is configured so that the entire non-contact automatic ticket gate G can be controlled in an integrated manner.
[0018]
2 is an enlarged plan view of the antenna part a of FIG. 1, and FIG. 3 is a cross-sectional view taken along line AA of FIG. The antenna part a has a loop coil L wound around the back side of the rectangular synthetic resin plate 1 (in FIG. 2 and FIG. 3, one time for simplifying the drawing). A mark for informing the user of the position of the antenna part a is engraved on the surface of the synthetic resin plate 1 (see FIG. 2).
[0019]
The metal plate 2 a is made of an aluminum plate, has a rectangular shape that is the same as that of the synthetic resin plate 1, and is provided below the synthetic resin plate 1 at a predetermined interval. The metal plate 2b is also made of an aluminum plate, corresponds to the auxiliary metal plate of the present invention, and is provided so as to surround the periphery of the synthetic resin plate 1 and the metal plate 2a. In the present invention, the term “metal plate” or “auxiliary metal plate” includes not only a metal such as aluminum but also a material having a predetermined magnetic permeability.
[0020]
In FIG. 3, T is a transmitter, which is provided on the back surface of the metal plate 2a, that is, on the metal plate 2a opposite to the synthetic resin plate 1 (loop coil L) side.
[0021]
FIG. 4 is a detailed view of the loop coil L. The loop coil shown here is shown as loop coils L1 to L3 wound three times in order to simplify the drawing. Resonant elements 3a to 3c each including a capacitor having a predetermined capacity are connected in series for each turn (winding).
[0022]
As shown in FIG. 5, the resonance elements 3a to 3c may be resonance elements 3a ′ to 3c ′ in which a resistor having a predetermined resistance value is connected in parallel. As described above, when the resistors are arranged in parallel, the transmitter can be protected from the inrush current, which will be described in detail later.
[0023]
The loop coil L has a function of a transmission loop antenna for supplying power to the contactless card C and transmitting data. In addition to the transmission loop coil L, an antenna for receiving data from the non-contact card C is also stretched on the back surface of the synthetic resin plate 1, but is omitted here. Therefore, a receiving circuit is also omitted in the transmitter T described later.
[0024]
The transmitter T modulates a carrier wave having a predetermined frequency (for example, 13.56 MHz) with data to be transmitted to the contactless card C, and amplifies the signal output from the modulation circuit 4 An amplifier circuit 5 is included.
[0025]
Since the antenna device A having the above configuration is connected in a state where a plurality of resonance elements 3a to 3c are dispersed in series, even if an excessive voltage is applied, the voltage is dispersed. It is possible to effectively prevent 3c (or 3a ′ to 3c ′) from being destroyed.
[0026]
Further, when a single loop coil is formed as in a conventional loop coil type antenna device, when the loop coil or the resonant element is short-circuited, the loop coil stops the function of the antenna. Furthermore, since the loop coil L is divided into a plurality of pieces (L1 to L3), the function of the antenna can be maintained even if one of the loop coils is short-circuited.
[0027]
Furthermore, since the antenna device A having the above configuration divides the loop coil L into a plurality of (L1 to L3) as described above, the inductance of each of the loop coils L1 to L3 can be reduced, and a large electric power can be obtained as a whole. It can be supplied to the loop coil L, and therefore has a feature that the communication distance can be increased.
[0028]
Further, since the antenna device A having the above configuration is shielded by the metal plates 2a and 2b except in the direction in which the non-contact card C is held, the antenna device A can be installed close to other metal objects. The resonance frequency does not shift, so that readjustment after installation of the antenna device A can be omitted, and the influence on the transmitter can be prevented.
[0029]
Further, since the resonance elements 3a 'to 3c' shown in FIG. 5 have a resistance interposed, when an inrush current due to static electricity or the like is applied to the loop coil L, this can be regarded as a heat loss. T can be effectively protected.
[0030]
In the antenna device A having the above configuration, in addition to the above-described features, the greatest feature is that the communication distance can be increased. That is, the length of the communication distance corresponds to the height of the communication area (1) shown in FIG. 3, and if this height increases, the communication between the non-contact automatic ticket gate G and the non-contact card C is achieved. Means easy to do.
[0031]
The mechanism for improving the communication distance in the antenna device A having the above configuration is not necessarily clear, but the magnetic field form changes due to the division of the loop coil L and the provision of the metal plate 2a below the loop coil L. It is thought that it was because.
[0032]
FIG. 6 shows a directivity pattern of the loop coil L of the antenna device A having the above configuration. In FIG. 6, “a” indicates the height (corresponding to the communication distance) at the axis of the loop coil L. In addition, in FIG. 6, B is a value when it is one conventional loop coil and does not have a metal plate under the loop coil. As is apparent from FIG. 6, it can be seen that the antenna apparatus A according to the present invention is improved in the communication distance by a factor of two or more compared to the conventional art.
[0033]
The loop coil L shown in FIG. 7 has the resonance elements 3a to 3c shown in FIG. 4 or the resonance shown in FIG. 5 at a predetermined interval in the middle of the loop coil L ′ wound a plurality of times. This is an example in which elements 3a 'to 3c' are provided. Also in this case, the same effect as when the resonant elements 3a to 3c (or 3a 'to 3c') are provided for each turn of the loop coil L can be obtained.
[0034]
Although not shown, the above-described resonance elements 3a to 3c (or 3a 'to 3c') may be provided every several turns, for example, every two turns. In this case, the number of turns can be increased.
[0035]
【The invention's effect】
The antenna device for a non-contact type automatic ticket gate according to claim 1 of the present invention connects a capacitor and a resistor in parallel for each turn of a loop coil wound in a plurality of turns or for every predetermined number of turns. Rutotomoni provided resonant elements, among the planes of their loop coils wound plurality, disposed a metal plate with a predetermined spacing on a surface opposite to the side to be held over the said non-contact type card, Further, since the auxiliary metal plate is provided between the side surface of the loop coil wound around the plurality and the metal plate, an antenna device suitable for the non-contact type automatic ticket gate can be obtained.
[0036]
Claim 2 noncontact automatic ticket gate antenna device according to the present invention, Rutotomoni provided plurality of wound loop coil plurality of arbitrary positions on the resonant element connected to a capacitor and a resistor and in parallel A metal plate is disposed on the surface opposite to the side of the non-contact card among the planes of the loop coils wound around the plurality, and is further wound around the plurality. Since the auxiliary metal plate is provided between the side surface of the loop coil and the metal plate, an antenna device suitable for a non-contact automatic ticket gate can be obtained.
[0037]
Non-contact antenna device for an automatic ticket gate machine according to claim 3 of the present invention, the surface opposite to the side where the loop coil is provided in the metallic plate, a transmitter for generating a signal to be supplied to the loop coils since is provided, it is possible to protect the transmitter.
[Brief description of the drawings]
FIG. 1 is a perspective view of an antenna device according to an embodiment of the present invention when applied to a non-contact automatic ticket gate.
FIG. 2 is an enlarged plan view of an antenna unit.
FIG. 3 is a cross-sectional view taken along line AA in FIG.
FIG. 4 is a detailed view of a loop coil.
FIG. 5 is another example of a resonant element.
FIG. 6 is an explanatory diagram showing directivity of a loop coil.
FIG. 7 is another example of a loop coil.
[Explanation of symbols]
G Non-contact type automatic ticket gate G 'Upper surface of casing C Non-contact type card A Antenna device a Antenna unit 1 Synthetic resin plates 2a and 2b Metal plates 3a to 3c, 3a' to 3c 'Resonant elements L (L1, L2,. L3) Loop coil T Transmitter 4 Modulation circuit 5 Amplification circuit

Claims (3)

In an antenna device for a non-contact type automatic ticket gate that transmits a signal to a non-contact type card in a non-contact manner via an antenna composed of a loop coil wound in a plurality of ways,
Per each turn of the loop coil wound around the plurality, or every predetermined plurality of windings providing a resonant element connected to a capacitor and a resistor and in parallel Rutotomoni, plurality wound loop coil thereof Among the planes, a metal plate is disposed at a predetermined interval on the surface opposite to the side of the non-contact card, and a side surface of the loop coil wound around the plurality and the metal plate An antenna device for a non-contact automatic ticket gate , wherein an auxiliary metal plate is provided between them . In an antenna device for a non-contact type automatic ticket gate that transmits a signal to a non-contact type card in a non-contact manner via an antenna composed of a loop coil wound in a plurality of ways,
The plurality to any of a plurality of positions of the wound loop coil provided a resonant element connected to a capacitor and a resistor and in parallel Rutotomoni out of the plane of the wound loop coil plurality, the non-contact A metal plate is arranged on the surface opposite to the side where the card is held, with a predetermined interval, and an auxiliary metal plate is provided between the side surface of the loop coil wound around the card and the metal plate. An antenna device for a non-contact automatic ticket gate characterized by the above. The antenna device for a non-contact type automatic ticket gate according to claim 1 or 2, wherein a signal supplied to the loop coil is generated on a surface of the metal plate opposite to the side where the loop coil is provided. An antenna device for a non-contact type automatic ticket gate, wherein a transmitter is provided .

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