JP3788091B2 - Data communication device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a data communication apparatus used in a distribution system, an electronic coupon ticket system, a cafeteria-style cafeteria clearing system, and the like.
[0002]
[Prior art]
Conventionally, in an article identification system, an electronic coupon ticket system, or the like used in an assembly conveyance line or a distribution system, a system for identifying and managing articles is required. Therefore, a tag (also referred to as a data carrier or ID card) having a memory as an identification target is provided as in JP-A-1-163991, and non-contact data transmission is performed by electromagnetic induction, and necessary information is written on the tag. An identification system has been proposed in which the information is read as necessary. Such a tag is attached to a baggage, a pallet, or the like, or is possessed by a user, and the necessary data is written to the tag from a data communication device arranged on the side of a conveyance route of the baggage or the entrance / exit gate. Configured to read.
[0003]
[Problems to be solved by the invention]
In such a conventional identification system, the data communication apparatus uses a transmission coil and a reception coil, and there is a case where a set of coil units in which these coils are integrally formed is used. Then, as shown in FIG. 5, the transmission coil 101 and the reception coil 102 are arranged so as to be coaxial on substantially the same plane.
[0004]
However, when the transmitting and receiving coils are arranged on the same plane, the side lobe 103 capable of communicating with the tag is used as a communication area in addition to the main beam 104 of the receiving coil. When it is desired to limit the communication area with the tag, there is a drawback that such side lobes may cause malfunction.
[0005]
The present invention was made in view of such conventional problems, and an object thereof is to make the invention of claim 1 does not cause unwanted communication area by the side lobes. The invention of claim 2 and 3, in addition to these problems, and an object thereof is to provide a data communication apparatus which can be applied to clearing system.
[0006]
[Means for Solving the Problems]
The invention of claim 1 of the present application is a data communication device that performs non-contact data communication with a tag by electromagnetic induction, and has a transmission coil, and a transmission unit that drives the transmission coil based on transmission data; A receiving unit that receives a signal from a tag based on a signal from the receiving coil, and arranges the transmitting coil in front of a communication area, and the receiving coil is a transmitting coil. The receiving coil surface is parallel to the transmitting coil, and is placed behind the communication area. The distance between the transmitting coil and the receiving coil is the center portion of the side lobe formed by the receiving coil. It is characterized in that it can communicate with the tag only within the range of the main beam of the receiving coil .
[0008]
The invention according to claim 2 of the present application is the data communication device according to claim 1 , wherein the tag holds charge data of a product to which the tag is attached, and the data communication device is detected by the receiving unit. It has a charge calculation means for calculating a charge based on the charge data of the tag.
[0009]
The invention according to claim 3 of the present application is the data communication apparatus according to claim 2 , further comprising charge display means for displaying the charge calculated by the charge calculation means.
[0010]
According to the first aspect of the present invention having such characteristics, the transmitting coil is disposed on the front surface of the communication area, and the receiving coil is disposed behind the transmitting coil. Therefore, by appropriately selecting the interval between the transmitting and receiving coils, the communication area can be limited so that the side lobe does not protrude into the communication area. According to the inventions of claims 2 and 3 , when a tag holding fee data is present in the communication area, the fee is calculated for each purchase based on the fee data from the tag, and further displayed. it can.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a block diagram showing the configuration of the data communication apparatus according to the first embodiment of the present invention, and FIG. 2 is a diagram showing its transmission / reception coil. As shown in these drawings, the data communication apparatus 11 includes an ID controller 12, a transmission unit 13, and a reception unit 14. The transmission unit 13 includes a modulation circuit 21, a drive circuit 22, and a transmission coil L1. The modulation circuit 21 is supplied with the modulation signal MOD and the pulse width modulation signal PWM from the ID controller 12, performs pulse width modulation based on the PWM signal at the time of transmission, and outputs a signal with a constant duty ratio of the PWM signal at the time of reception. Is output. The drive circuit 22 amplifies this signal and drives the transmission coil L1. On the other hand, the receiving unit 14 has a receiving coil L2 as shown in the figure, and a received signal at the timing when the carrier is stopped is given to the filter circuit 32 via the amplifier circuit 31. The filter circuit 32 includes a band pass filter (BPF) whose pass frequency is the frequency of the carrier output from the transmission unit 13, and its output is input to the detection circuit 33. The detection circuit 33 performs envelope detection of this signal, and its output is given to the ID controller 12 via the A / D converter 34. The ID controller 12 outputs a transmission signal as a PWM signal to the transmission unit at the time of transmission, and receives a signal from the tag based on the signal level obtained via the A / D converter at the time of reception.
[0012]
Now, as shown in FIG. 2A, the transmission / reception coil used in the present embodiment has a transmission coil L1 arranged on the front side of the communication area and a fixed back behind the transmission coil L1, as shown in FIG. The receiving coil L2 is arranged with a gap d. The distance d is set to be equal to or higher than the height of the side lobe 41 formed by the receiving coil L2. The region where the power and data can be transmitted from the transmission coil L1 is the main beam 41 and the side lobe 42, and the region where the reception coil L2 data can be received is the region overlapping the main beam 43 and the side lobe 44. . Here, since the receiving coil L2 is arranged behind the communication area by a distance d, the side lobe 44 is removed from the receivable area generated by the receiving coil L2, and the upper part of the main beam 42 overlapping the main beam 41 of the transmitting coil L1. Only the area is the communication area. That is, since the side lobe does not protrude on the communication surface with the tag, data communication cannot be performed with the side lobe 44 generated only by the receiving coil L2.
[0013]
Further, since the transmission coil is arranged on the communication area side, the transmission level can be increased. By increasing the transmission level in this way, the reception level that is the reverberation can also be increased, and the ratio (S / N ratio) between the reception level and the noise can be improved.
[0014]
As described above, in this embodiment, since the receiving area of the receiving coil is smaller than the main beam 41 and the side lobe 42 capable of transmitting power and data from the transmitting coil L1, data is transmitted to all tags in the transmittable area. When writing, malfunction occurs. Therefore, when reading the ID code of the tag, it is necessary to use it for the purpose of confirming the ID code of the tag and writing data to the tag.
[0015]
Next, an automatic checkout system for a cafeteria-style cafeteria using a data communication apparatus according to a second embodiment of the present invention will be described. In this embodiment, as shown in FIG. 3 (a) or (b), tags holding data such as types and prices are provided on the back surfaces of all food and drink dishes and cups provided in advance in the cafeteria. Embed it. Then, plates 53, 54, cups 55, etc., which are arbitrarily selected by the user, are placed on the tray 52 on the transport table 51 and placed at the clearing position. As described above, the transmission coil L1 and the reception coil L2 are arranged below the clearing position of the transport table 51. Here, one tray 52 and the transmission coil L1 are set to have substantially the same shape. 1 is connected to the transmission / reception coil, and the ID controller 12 is connected to the computer of the clearing system.
[0016]
FIG. 4 is a block diagram showing the overall configuration of a data communication apparatus applied to this clearing system. The same parts as those in the first embodiment described above are denoted by the same reference numerals and description thereof is omitted. In this embodiment, the transmitter 13 and the receiver 14 are connected to the ID controller 12, and the computer 60 of the clearing system is further connected. An input unit 61, an output unit 62, and a display device 56 that is a charge display means are connected to the computer 60 of the clearing system. It is assumed that the computer 60 achieves the function of the charge calculation means 60a for calculating the charge by adding the charge data of a plurality of tags for each clearing unit based on the charge data of each tag at the clearing position.
[0017]
In this way, the clearing position where the tray 52 is placed can be set as the communication area, and the fee can be calculated from the data of the tag attached to the tableware included in the tray 52. In this case, by using the receiving unit 14 of the first embodiment as the data communication device, the tag data can be reliably read at the clearing position. Since the side lobe is out of the communication area, the charges of the tags attached to the plates of the adjacent trays 57 are not erroneously added.
[0018]
In the second embodiment, since a plurality of tags are included in one communication area, it is necessary to identify them. For this reason, a unique ID code may be provided for each tag. Further, as disclosed in Japanese Patent Laid-Open No. 10-224279, an ID code may be provided for each tag, and the tag may be discriminated using a part thereof. That is, a part of the ID code of the tag is decoded and returned to the data communication apparatus side as a temporary identification number. Even if there are a plurality of tags in the communication area, the decoding results often do not match, so a tag is selected according to the signal. If the decoding results match, the ID code area for generating the temporary identification number is changed. In this way, even if there are a plurality of tags in the communication area, data communication with each tag can be performed sequentially.
[0019]
Further, even when the tableware in the cafeteria canteen is washed and dried, the tag information is used for the tableware automatic sorter, so that the tableware can be sorted for each type of tableware, and the management of the tableware becomes easy.
[0020]
The present invention is not limited to a cafeteria-style cafeteria clearing system, and can be applied to cashier clearing processing when purchasing goods at a large-scale retail store. In addition, the present invention can be applied to various uses in which a certain area is used as a communication area, such as a management of clothing requested to be cleaned in a cleaning store or the like, or a product management of various rental items.
[0021]
【The invention's effect】
As described above in detail, according to the first aspect of the present invention, the side lobes can be prevented from protruding into the communication region by selecting the interval between the transmitting and receiving coils. Therefore, it is possible to prevent malfunctions due to side lobes. Further, according to the inventions of claims 2 and 3 , the fee can be calculated based on the fee data of the tag in the communication area and can be displayed, and can be applied to various settlement systems.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a configuration of a data communication apparatus according to a first embodiment of the present invention.
FIGS. 2A and 2B are a top view and a side view showing an arrangement and a communication area of a transmission coil and a reception coil according to the present embodiment.
FIG. 3 is a schematic view showing a cafeteria automatic settlement system according to a second embodiment of the present invention.
FIG. 4 is a block diagram showing an overall configuration of a cafeteria automatic settlement system according to a second embodiment.
FIG. 5 is a schematic diagram showing a receiving coil and a communication area of a conventional data communication apparatus.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 11 Data communication apparatus 12 ID controller 13 Transmission part 14 Reception part 21 Modulation circuit 22 Drive circuit 31 Amplification circuit 32 Filter circuit 33 Detection circuit 34 A / D converter 41,43 Main beam 42,44 Sidelobe L1 Transmission coil L2 Reception coil

Claims (3)

A data communication device that performs non-contact data communication with a tag by electromagnetic induction,
A transmission unit having a transmission coil and driving the transmission coil based on transmission data;
A receiving unit having a receiving coil and receiving a signal from the tag based on the signal from the receiving coil;
The transmission coil is disposed in front of the communication area, the reception coil is coaxial with the transmission coil, the reception coil surface is parallel to the transmission coil, and is disposed behind the communication area, and the transmission coil and the reception coil The center portion of the side lobe formed by the reception coil is directed to the outside of the transmission coil so that communication can be performed with the tag only within the range of the main beam of the reception coil. A data communication device. The tag holds price data of a product to which the tag is attached,
The data communication apparatus, data communication apparatus according to claim 1, wherein the one having a charge calculation means for calculating a fee based on the fee data of tags detected from the reception unit. The data communication apparatus according to claim 2 , further comprising a charge display means for displaying the charge calculated by the charge calculation means.

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