JP2002133380A - Electromagnetic wave transmitter/receiver - Google Patents

Abstract

PROBLEM TO BE SOLVED: To transmit and receive an electromagnetic wave efficiently by reliably preventing leakage of the electromagnetic wave. SOLUTION: When a load 30a with an IC card affixed is carried in from an opening 18 of an IC card reader/writer 10 in an arrow A direction, the load 30 is passed through stripped conductive sheets 18 and 20 arranged over openings 14, until carried in near to an antenna 12 in a casing. A canceler 26 can cancel a magnetic field emitted by the antenna 12 by generating the opposite magnetic field to thus reduce a radio wave leaking out. After reading and writing processing on IC card data via the antenna 12, an IC card-affixed load 30b is passed and carried out through a stripped conductive sheet 22, a canceler 28 and a conductive sheet 22 all arranged down before an opening 16. Even if a gap is caused when the load is passed through any conductive sheet, the other conductive sheets and the cancelers can function to reliably prevent the radio wave from leaking out.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electromagnetic wave transmitting / receiving apparatus, and more particularly, to an electromagnetic wave transmitting / receiving apparatus for transmitting / receiving electromagnetic waves to / from an object via an antenna in a housing having an opening through which the object is inserted and removed. Related to the device.

[0002]

2. Description of the Related Art Conventionally, there has been known an electromagnetic wave transmitting and receiving apparatus for transmitting and receiving electromagnetic waves in a shielded container shielded so that the electromagnetic waves do not leak to the outside. As this type of electromagnetic wave transmission / reception device, for example, there is an IC card reader / writer which reads and writes IC card data in a non-contact manner, and forms an AC magnetic field to generate electric power at an antenna of the IC card, which is transmitted to an IC chip. By supplying and driving,
It enables reading and writing of IC card data without contact. FIG. 4 is a perspective view illustrating a schematic configuration of a conventional electromagnetic wave transmitting / receiving device 60. The electromagnetic wave transmission / reception device 60 shown in FIG. 4 is formed of a housing having a hollow quadrangular prism shape using a metal material having high conductivity such as aluminum,
A coil-shaped antenna 62 of an IC card reader / writer is installed in a band shape near the center of the housing. Then, as shown in FIG. 4, the luggage 80 to which the IC card 82 is attached is conveyed from the opening 64 in the direction indicated by the outline arrow C, and placed at a reading position near the center of the casing of the electromagnetic wave transmitting / receiving device 60. , The read / write processing of the IC card is started. The procedure of the read / write process is as follows. When an AC magnetic field is formed by the IC card reader / writer, power is generated in the antenna on the IC card 82 side and supplied to the IC chip to be in a movable state. In this state, the IC card reader / writer communicates with the IC chip via an electromagnetic wave.
A reading process and a writing process of the card data are performed.
In this way, the luggage 80 with the IC card 82 that has completed the data read / write processing is carried out to the outline arrow D from the opening 66 on the opposite side, and the luggage with the new IC card is moved from the direction of the outline arrow A in the direction of the outline arrow A. It is carried in and the next read / write processing is performed. If a belt conveyor or the like is used to transport the load, a large number of IC cards can be read and written automatically and continuously.

[0003]

However, in such a conventional electromagnetic wave transmitting / receiving apparatus, as shown in FIG. 4, an IC card reader / writer generates an AC magnetic field to generate an I.C.
When power is supplied to the C card and electromagnetic waves (for example, radio waves) are transmitted and received to read and write data, there is a problem that the electromagnetic waves leak to the outside from the openings 64 and 66 on both sides. For this reason, conventionally, devices for canceling electromagnetic waves generated from an IC card reader / writer, so-called cancellers 68 and 70 are provided on both sides of an antenna 62 installed at the center of the housing in FIG. 4 to prevent leakage of electromagnetic waves. Was. However, simply installing the cancellers 68 and 70 cannot reliably prevent leakage of electromagnetic waves, and may cause problems in relation to the Radio Law and the like. The present invention has been made in view of the above circumstances,
An object of the present invention is to provide an electromagnetic wave transmitting / receiving device capable of performing efficient processing by reliably preventing leakage of electromagnetic waves.

[0004]

In order to achieve the above object, the invention according to claim 1 transmits and receives electromagnetic waves to and from an object via an antenna in a housing having an opening through which the object is inserted and removed. In the electromagnetic wave transmitting and receiving apparatus described above, the opening is provided with a shielding member that shields the electromagnetic wave generated in the housing and prevents the object from leaking out while allowing the object to be taken in and out. According to this,
For example, because a shield member that shields electromagnetic waves generated in the housing and prevents leakage to the outside is arranged in the opening while allowing the attached object such as an IC card to be taken in and out,
Leakage of electromagnetic waves generated when reading and writing IC card data and the like can be reliably prevented. According to a second aspect of the present invention, in the electromagnetic wave transmitting / receiving apparatus according to the first aspect,
An opening is provided before and after the housing. According to this, since an opening is provided before and after the housing, for example, an object to which an IC card or the like is attached is inserted from one opening, and after reading and writing processing of the IC card data, the other is performed. Since a series of operations of discharging from the opening can be continuously processed in one way, efficient processing can be performed. The invention according to claim 3 is the invention according to claim 1 or 2
In the electromagnetic wave transmission / reception device described in (1), the shield member is formed such that a flexible conductive sheet is cut into a strip shape to cover the opening. According to this, a flexible conductive sheet is used as the shield member, which is cut into strips and arranged so as to close the opening, so that the object can be taken in and out, and the electromagnetic waves generated in the housing can be obtained. To prevent leakage to the outside.

[0005] The invention according to claim 4 is the invention according to claim 1 or 2.
In the electromagnetic wave transmitting and receiving device according to the above, the shield member is arranged so that an opening / closing door made of a conductive material closes the opening, and is provided with a mechanism that opens and closes only when the object passes. I do. According to this, an opening / closing door made of a conductive material is arranged as a shield member so as to close the opening, and is provided with a mechanism that opens and closes when an object passes, so that the object can be taken in and out,
Electromagnetic waves generated in the housing can be shielded to prevent leakage to the outside. According to a fifth aspect of the present invention, in the electromagnetic wave transmitting / receiving device according to any one of the first to fourth aspects, the shield member is arranged in a plurality of layers in the opening. According to this, since the shielding member is arranged in a plurality of layers with respect to the opening, the shielding effect of the electromagnetic wave can be further enhanced, and when the object is continuously processed, an IC card or the like attached to the object is used. During the read / write processing, even if an object before or after the read / write process passes through the opening, leakage of the electromagnetic wave can be prevented. According to a sixth aspect of the present invention, in the electromagnetic wave transmitting / receiving apparatus according to any one of the first to fifth aspects, the shield member is grounded. According to this, since the shield member is grounded to the ground, the electromagnetic wave generated inside can be efficiently caught and shielded so as not to leak outside. According to a seventh aspect of the present invention, in the electromagnetic wave transmitting / receiving apparatus according to any one of the first to sixth aspects, a canceller for canceling an internally generated electromagnetic wave is provided between the antenna and the opening in the housing. It is further characterized by being provided. According to this, since the canceller for canceling the electromagnetic wave generated inside is further provided between the antenna in the housing and the opening, the shielding effect of the electromagnetic wave is further enhanced by the synergistic effect with the shield member, and the outside is provided. Electromagnetic waves can be reliably prevented from leaking.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings. As the electromagnetic wave transmission / reception device of the present embodiment, for example, while a package with a non-contact type IC card
An IC card reader / writer that automatically manages the delivery of packages by reading and writing card data will be described as an example. FIG. 1 is a perspective view illustrating a schematic configuration of an IC card reader / writer 10 according to the present embodiment. In FIG. 1, an IC card reader / writer 10
Is formed in a quadrangular prism shape using a metal material having high conductivity such as aluminum, and has a hollow structure inside. Further, a coil-shaped antenna 12 of an IC card reader / writer is installed in a band shape near the center of the housing. Shield members are arranged in the front and rear openings 14 and 16 of the housing so as to close the openings.
The shield member shown in FIG. 1 is a conductive sheet 1 having flexibility.
8 (similarly for 20, 22, and 24) is used, which is cut into strips and hang down from the top to the bottom of the opening.
As the conductive sheet, for example, in the case of a non-conductive resin sheet or cloth, a conductive coating is applied, or a woven cloth having conductivity using metal fibers may be used. it can. This allows I
It is possible to obtain a shield member that shields radio waves (electromagnetic waves) emitted from the antenna 12 of the IC card reader / writer 10 while allowing the luggage (object) attached with the C card 32 to be taken in and out. Further, in the present embodiment, the conductive sheets 18, 20, 22, and 24 are arranged in a plurality of layers at predetermined intervals. This not only enhances the radio wave shielding effect, but also creates a gap in the strip-shaped conductive sheet 18 when the luggage 30 to which the IC card 32 is attached passes through the conductive sheet 18 as shown in FIG. However, since the radio wave is shielded by the next conductive sheet (here, the conductive sheet 20), it is possible to reliably prevent the radio wave from leaking to the outside even when the luggage is continuously processed. it can. Further, in the present embodiment, a canceller 2 for canceling a radio wave emitted from the antenna 12 of the IC card reader / writer 10 is provided between the conductive sheets 18 and 20 and the conductive sheets 22 and 24 described above.
6, 28 are further provided. This is because even if the canceller alone does not provide a sufficient radio wave shielding effect, the synergistic effect combined with the conductive sheets 18 to 24 of the present embodiment further enhances the radio wave shielding effect, and the electromagnetic wave leaks to the outside. Is reliably prevented.

In FIG. 1, a belt conveyor is used for transporting the luggage 30, but is omitted because the drawing becomes complicated. As a shield member for closing the opening, FIG.
For example, instead of the strip-shaped conductive sheets 18 to 24 shown in FIG.
A plurality of layers 2, 44, 46, 48 may be arranged at predetermined intervals. The material of the door is made of a metal material (shield member) having high conductivity such as aluminum or copper. The opening / closing door 42 includes, for example, a pair of left and right doors 42a, 42b having hinges 42c, 4 respectively.
It is configured to be rotatable about 2d, and is always urged by a spring or the like in a direction to close the door. Thus, the doors 42a and 42b are pushed open only when the luggage 30 passes, but the doors 42a and 42b are closed immediately after passing. As a result, the radio wave shielding effect can be enhanced, and as shown in FIG. 2, even if a gap occurs when the luggage attached with the IC card passes through the open / close doors 42a, 42b. Since the doors 44a and 44b are closed, radio waves can be shielded here. further,
When the luggage 30 is conveyed to the back and the doors 44a and 44b are opened, the front doors 42a and 42b are closed, so that even if the luggage is continuously processed, radio waves are prevented from leaking to the outside. be able to. Here, the door 42
Since the overlapping portion between a and 42b (similarly in the case of 44, 46, 48) is large, a further effect of preventing radio wave leakage can be obtained.

FIG. 3 is an internal sectional view of the IC card reader / writer shown in FIG. 1 or 2 as viewed from the side. As shown in FIG. 3, the housing of the IC card reader / writer 10 (40), and the conductive sheets 18 to 24 and the doors 42 to 42
Reference numeral 48 is grounded to the ground. In the present embodiment, the IC card reader / writer 10
Although (40) is shaped like a square pole and the opening is square, it is needless to say that the opening is not limited to this shape, and the opening may be circular or polygonal. To 24 and the doors 42 to 48 may have the same shape, and any shape may be used as long as the opening can be closed by the conductive sheet or the door.

Next, the operation of this embodiment will be briefly described. First, as shown in FIG. 3, the luggage 30 to which the IC card 32 is attached is carried in by a belt conveyor from the opening 18 of the IC card reader / writer 10 in the direction of a white arrow A. At this time, the luggage 30 is carried into the inside of the housing by dipping between the strip-shaped conductive sheets 18 provided in the opening 14 (see the position of the luggage 30a in FIGS. 1 and 3).
The antenna 12 of the IC card reader / writer 10 generates an AC magnetic field to generate power in the IC card 32 of the luggage 30b (see FIG. 3) that has come near the antenna 12 to put the IC chip into a movable state. Read / write processing is performed without contact. At this time, a magnetic field is generated inside the IC card reader / writer 10, but by canceling the reverse magnetic fields generated by the cancelers 26 and 28 provided before and after the antenna 12, the radio waves leaking to the outside are reduced. Can be reduced. In the present embodiment, since the conductive sheet 20, the canceller 26, and the conductive sheet 18 are arranged in this order between the antenna 12 that generates the magnetic field and the opening 14, the luggage 30a is Even if the vehicle is being carried under a dive (or the conductive sheet 20), the remaining conductive sheet 20 (or the conductive sheet 18) and the canceller 26 reliably prevent radio waves from leaking to the outside. be able to. The same applies to the area between the antenna 12 that generates the magnetic field and the opening 16 on the opposite side. Since the conductive sheet 22, the canceller 28, and the conductive sheet 24 are arranged in this order, the luggage 30c becomes conductive. Even when the sheet is being carried out under the conductive sheet 22 (or the conductive sheet 24), the remaining conductive sheet 24 (or the conductive sheet 22) and the canceller 28 reliably prevent radio wave leakage. be able to. Further, as shown in FIG. 2, the doors 42, 44, 46, 48 made of a conductive material.
1 is substantially the same as the case of FIG. 1 described above.
Even if the package with the C card is conveyed, the leakage of the radio wave can be reliably prevented by the remaining opening and closing door and the canceller. When this door is used, the door that has been opened immediately after the baggage has passed automatically closes automatically by the biasing force, and then the next door is pushed open, so that the effect of preventing radio wave leakage is particularly large. At the position of the antenna 12 shown in FIG.
The luggage 30b with the card 32 passes through the conductive sheet 22, the canceller 28, and the conductive sheet 24, and the luggage 30c
As shown in the figure, the sheet is carried out from the opening 16 on the opposite side by a belt conveyor in the direction of a white arrow B. Such an IC card 32
When the luggage 30 with the IC card 32 is continuously processed, the luggage 30 with the IC card 32 is placed at a predetermined interval on a belt conveyor (not shown), and the IC card reader / writer 10 conveys the luggage 30 while conveying the luggage. Data read / write processing is sequentially repeated.

As described above, according to the present embodiment, when reading and writing data of the IC card 32 attached to the luggage 30 by the IC card reader / writer 10, the opening is formed by the conductive member having the shield member. In addition to allowing the luggage to be taken in and out by the flexible sheet and the opening / closing door, it is closed so that radio waves do not leak.
The synergistic effect of 6, 28 is added, and it is possible to reliably prevent radio waves from leaking to the outside. Further, according to the present embodiment, the IC card reader / writer 10
Since the IC card data can be read and written while continuously transporting a plurality of packages to which the card is attached, efficient processing can be performed. In the present embodiment, a conductive sheet or an opening / closing door is taken as an example of the shield member for closing the opening. However, the present invention is not necessarily limited to this, and other shield members, installation numbers, and installation positions are not limited to this. Alternatively, the present invention may be implemented by changing the combination with other radio wave shielding means.

[0011]

As described above, according to the first aspect of the present invention, it is possible to insert and remove an attached object such as an IC card, and to shield an electromagnetic wave generated in the housing to leak to the outside. Since the shield member is disposed at the opening, the leakage of electromagnetic waves generated when reading or writing IC card data or the like can be reliably prevented. Claim 2
According to the described invention, since an opening is provided before and after the housing, an attached object such as an IC card is inserted from one opening, and after reading and writing processing of IC card data, the other is performed. A series of operations of discharging from the opening can be continuously processed in one way, so that efficient processing can be performed. According to the invention described in claim 3, a flexible conductive sheet is used as the shield member, which is cut into a strip shape and arranged so as to close the opening, so that the object can be taken in and out. Electromagnetic waves generated in the housing can be shielded to prevent leakage to the outside. According to the fourth aspect of the present invention, the opening / closing door made of a conductive material is disposed as a shield member so as to close the opening, and is provided with a mechanism that opens and closes when the object passes. It is possible to shield electromagnetic waves generated in the housing and prevent leakage outside. According to the fifth aspect of the present invention, since the shield member is arranged in a plurality of layers with respect to the opening, the shielding effect of the electromagnetic wave can be further enhanced, and when the object is continuously processed, it is attached to the object. During reading and writing processing of an IC card or the like, leakage of electromagnetic waves can be prevented even if an object before and after passing through the opening. According to the sixth aspect of the present invention, since the shield member is grounded to the ground, it is possible to efficiently capture the electromagnetic wave generated inside and shield it from leaking outside. According to the invention described in claim 7, since the canceller for canceling the electromagnetic wave generated inside is further provided between the antenna and the opening in the housing, the electromagnetic wave shielding effect is enhanced by the synergistic effect with the shield member. As a result, the electromagnetic wave can be reliably prevented from leaking to the outside.

[Brief description of the drawings]

FIG. 1 is a perspective view illustrating a schematic configuration of an IC card reader / writer according to an embodiment.

FIG. 2 is a perspective view illustrating a variation of a shield member in the IC card reader / writer of the present embodiment.

FIG. 3 is an internal cross-sectional view of the IC card reader / writer of FIG. 1 or 2 as viewed from the side.

FIG. 4 is a perspective view illustrating a schematic configuration of a conventional electromagnetic wave transmitting / receiving device.

[Explanation of symbols]

 10 IC card reader / writer, 12 antenna, 14, 16 opening, 18, 20, 22, 24 conductive sheet, 26, 28 canceller, 30 luggage, 30a, 30b, 30c luggage 32 IC card, 40 IC card reader / writer, 42a, 42b doors, 42c, 42d hinges, 44a, 44b doors, 46a, 46b doors, 48a, 48b doors.

Claims (7)

[Claims] 1. An electromagnetic wave transmitting / receiving apparatus for transmitting / receiving an electromagnetic wave to / from an object via an antenna in a housing having an opening for taking in / out the object, wherein the object can be taken in and out of the opening. An electromagnetic wave transmission / reception device, wherein a shielding member for shielding an electromagnetic wave generated in the housing to prevent leakage to the outside is provided. 2. The electromagnetic wave transmitting / receiving apparatus according to claim 1, wherein openings are provided before and after the housing. 3. The electromagnetic wave transmission / reception device according to claim 1, wherein the shield member is formed by cutting a flexible conductive sheet into a strip shape and closing the opening. 4. The shield member, wherein an opening / closing door made of a conductive material is disposed so as to close the opening, and includes a mechanism that opens and closes only when the object passes. 3. The electromagnetic wave transmitting / receiving device according to 1 or 2. 5. The electromagnetic wave transmitting / receiving device according to claim 1, wherein a plurality of the shield members are arranged in the opening. 6. The electromagnetic wave transmission / reception device according to claim 1, wherein the shield member is grounded. 7. The device according to claim 1, further comprising a canceller for canceling an electromagnetic wave generated inside between the antenna and the opening in the housing. An electromagnetic wave transmitting / receiving device according to any one of the preceding claims.