JP4616366B2 - Electric field communication device - Google Patents

Description

  The present invention relates to an electric field communication device for performing communication by inducing an electric field in an electric field transmission medium.

  Conventionally, there has been proposed an electric field communication system in which an electric field is induced in an electric field transmission medium such as a human body and various information communication is performed via the induced electric field. This electric field communication system has electric field communication devices equipped with transmission means and / or reception means, and is similar to other people and equipment (PCs, station ticket gates, vending machines, doors, gates, etc.) Owns or installs the electric field communication device, and performs information communication according to the purpose. This information communication makes it possible to collect data such as security authentication, billing, and location (see Patent Document 1).

  When such an electric field communication device is used as electric field communication means, the electric field communication device is provided with an electrode plate composed of a pair of a negative electrode and a positive electrode that are insulated from each other. When the human body touches the electrode, an electric field is induced in the human body to become an electric field transmission medium, and electric field communication is possible.

  An example of the configuration of a conventional electric field communication device is shown in FIG. FIG. 4A is a schematic cross-sectional view, and FIG. 4B shows the arrangement of the battery. In brief, the negative electrode 20 and the positive electrode 10 are housed inside the casing 100 of the electric field communication apparatus, and a drive circuit board 30 is disposed in the space between the two electrode plates. The drive circuit board 30 constitutes a circuit for driving the electric field communication device.

Circuit components 70 are arranged on the surface of the drive circuit board 30. Although not shown, the circuit components 70 are arranged on both sides of the drive circuit board 30 depending on the circuit configuration. As shown in FIG. 4B, the battery 40 is arranged on the circuit component 70 on the surface of the drive circuit board 30 to supply power.
JP 2006-81111 A

  However, the conventional technology as described above has a configuration in which a printed circuit board, a mounting component, a battery 40, etc. having a large relative dielectric constant and a poor insulating property are sandwiched between electrode plates, and as shown in FIG. The space L ′ between the side electrodes 10 cannot be sufficiently secured, and the output performance from the electrode plate may be lowered due to the increase in capacitance caused by the interval L ′.

  The present invention has been made in view of the above, and an object of the present invention is to reduce the capacitance between the electrode plates and realize good output characteristics.

In order to achieve the above object, the present invention described in claim 1 is an electric field communication device having an electrode plate for inducing communication in an electric field transmission medium to perform communication, and a pair of + side electrode plates and − The electrode plate constituted by a side electrode plate, a drive circuit board constituting a drive circuit for inducing an electric field in the electric field transmission medium, and the negative electrode plate provided on the entire one side of the drive circuit board and a ground plane for operation, the battery for supplying power to the driving circuit board that are juxtaposed without overlapping with the driving circuit board.

  According to the present invention, the capacity between the electrode plates can be reduced, and good output characteristics can be realized.

<First Embodiment>
FIG. 1 shows an overview for explaining a first embodiment of an electric field communication apparatus of the present invention. FIG. 1 shows a + side electrode 1 for coupling to an electric field transmission medium, a − side electrode 2 for coupling to a ground, and a drive circuit board arranged to be connected to both electrodes for electric field communication. 3 shows a configuration example of electric field communication means including 3 and a housing 8 for storing components necessary for electric field communication.

  The casing 8 is a substantially box-shaped container in which electrical insulation is maintained, and houses the drive circuit board 3, the + side electrode 1, and the − side electrode 2 therein. The size of the housing 8 is arbitrarily set depending on the application, but a small size is required when applied to the electric field communication means. For example, it is necessary for the user to be portable with a size equivalent to the credit card size.

  In order to house the constituent members for realizing the electric field communication means in the casing 8 having restrictions on the thickness and area, in particular, the drive circuit board 3, the + side electrode 1, and the − side electrode 2 are arranged. The housing 8 needs to be stored within a limited thickness range.

  On the other hand, in the electric field communication, the − side electrode 2 coupled to the ground (− side) and the + side electrode 1 coupled to the electric field transmission medium such as a human body are kept at a predetermined distance so as not to contact each other. Must be placed and stored internally.

  FIG. 2 shows an example of the configuration of the electric field communication apparatus according to the first embodiment of the present invention. 2A is a schematic cross-sectional view, and FIG. 2B shows an arrangement example of the battery 4.

  In this configuration, the negative electrode 2 is formed on the entire surface of one side of the drive circuit board 3. As a method of forming the negative electrode 2 on the entire surface of one side of the drive circuit board 3, one side is manufactured as a ground plane in the process of manufacturing the drive circuit board 3. Alternatively, no negative circuit pattern is formed on one side of the drive circuit board 3, and a metal foil or the like may be attached and adhered to the negative electrode 2.

  A circuit component 7 is disposed on the surface of the drive circuit board 3 opposite to the entire ground. The battery 4 is disposed on the drive circuit board 3 (see FIG. 2B). The battery 4 and the drive circuit board 3 are connected by a power supply lead wire or a circuit pattern. In FIG. 2A, the battery 4 is connected to the drive circuit board 3 with the positive electrode 5 facing upward and the negative electrode 6 facing downward.

  With the configuration shown in FIG. 2, the negative electrode 2 can be formed in close contact with the drive circuit board 3, so that the negative electrode 2 and the drive circuit board 3 are manufactured and arranged separately. Thus, the length in the thickness direction occupying the inside of the housing 8 can be shortened. The distance L between the positive electrode 1 and the battery 4 on the drive circuit board 3 can also be secured sufficiently longer than in the past. For this reason, the capacity | capacitance between the + side electrode 1 and the-side electrode 2 can be restrained low, and the transmission / reception characteristic as an antenna effect from an electrode can be made favorable.

<Second Embodiment>
FIG. 3 shows an example of the configuration of the electric field communication apparatus according to the second embodiment of the present invention. In the second embodiment of k, the arrangement of the batteries 4 is different from that of the first embodiment described above. Specifically, the battery 4 is not disposed on the drive circuit board 3, but is juxtaposed with the drive circuit board 3 in a notch portion of the drive circuit board 3. The negative electrode 6 of the battery 4 is connected to the negative electrode (ground surface) 2. As a result, the battery 4 can be separated from the + side electrode 1 by the thickness of the drive circuit board 3, so that the distance L between the battery 4 and the + side electrode 1 can be secured sufficiently longer than that of the first embodiment. In this case, the relative dielectric constant can be lowered.

  According to the embodiment of the present invention described above, the capacity between the electrode plates can be reduced, and good output characteristics can be realized.

BRIEF DESCRIPTION OF THE DRAWINGS The schematic for demonstrating embodiment of the electric field communication apparatus of this invention is shown. The schematic structure for demonstrating the 1st Embodiment of this invention is shown, (a) is a schematic sectional drawing, (b) shows the example of arrangement | positioning of a battery. The schematic structure for demonstrating the 2nd Embodiment of this invention is shown, (a) is a schematic sectional drawing, (b) shows the example of arrangement | positioning of a battery. The structural example by a prior art is shown.

Explanation of symbols

1 ... + side electrode 2 ...- side electrode (ground plane)
3 ... Drive circuit board 4 ... Battery 5 ... + Pole 6 ...- Pole 7 ... Circuit components 8 ... Case

Claims (1)

In an electric field communication apparatus having an electrode plate for inducing communication in an electric field transmission medium and performing communication,
The electrode plate constituted by a pair of + side electrode plate and-side electrode plate;
A drive circuit board constituting a drive circuit for inducing an electric field in the electric field transmission medium;
A ground surface provided on the entire surface of one side of the drive circuit board and operating as the negative electrode plate;
Equipped with a,
Field communication device battery for supplying power to the driving circuit board is characterized that you have been juxtaposed without overlapping with the driving circuit board.

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