JP2007079814A - Metal cap body - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a metal cap body capable of preventing communication inhibition of an IC tag and capable of preventing the size of thickness direction from increasing. <P>SOLUTION: The metal cap body 1 for holding the IC tag 30 with an antenna 31 in the body comprises: the cap main body 10 formed of a ferrous metal; a recessed part 11, which is formed by curving a surface part of a top side of the cap main body 10 inward, for storing the IC tag 30 by positioning the antenna 31 in approximately parallel to the surface part of the top side of the cap main body part 10; and a low magnetic permeability part 20, provided between the antenna 31 and an inner surface of the recessed part 11 and formed from a material of which magnetic permeability is lower than the cap main body part 10. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a metal lid that holds an IC tag therein.

The IC tag is also called RFID (Radio Frequency Identification), holds information that can identify an individual, and can read or write the information in a non-contact manner by radio waves or the like.
Such an IC tag is built in a manhole cover formed of an iron-based metal material. As a result, it is possible to read data on the buried object such as a common groove in which the lid is installed without removing the lid from the manhole.
On the other hand, when an IC tag is used in the vicinity of an iron-based metal material, there is a problem that communication waves are absorbed by the metal material and communication is hindered. In order to prevent this communication hindrance, it is known that a manhole cover is provided with a through hole to accommodate an IC tag, and both sides of the antenna coil of this IC tag are opposed to the inner surface of this through hole (for example, , See Patent Document 1).

  However, this conventional manhole cover, for example, when the antenna accommodates a label-like IC tag formed on a sheet-like base material, the IC tag is arranged so as to be substantially orthogonal to the surface portion on the front side of the manhole cover. Since it is necessary, there is a problem that the dimension in the thickness direction of the manhole cover becomes large.

JP-A-9-33279

  An object of the present invention is to provide a metal lid that can prevent communication inhibition of an IC tag and can prevent an increase in thickness direction dimension.

The present invention solves the above problems by the following means.
According to a first aspect of the present invention, in a metal lid for holding an IC tag having an antenna therein, a lid main body formed of iron-based metal and a surface portion on the front side of the lid main body are recessed. The antenna is provided between the antenna and the inner surface of the recess, and the magnetic permeability is provided between the recess disposed in the interior of the lid body portion substantially parallel to the front surface portion of the lid body portion and accommodating the IC tag therein. A metal lid, comprising: a low magnetic permeability portion made of a material smaller than the lid main body portion.

A second aspect of the present invention is the metal lid according to the first aspect, wherein the antenna is a loop antenna.
According to a third aspect of the present invention, in the metal lid according to the first or second aspect, the low magnetic permeability part includes a molded product in which the IC tag is sealed. It is a lid.
The invention of claim 4 is characterized in that, in the metal lid according to any one of claims 1 to 3, the low magnetic permeability part is detachable from the lid body part. It is a metal lid.
According to a fifth aspect of the present invention, in the metal lid according to any one of the first to fourth aspects, the low magnetic permeability portion is formed of a rubber-based material. It is a metal lid.

As described above, the present invention has the following effects.
Since a low magnetic permeability part is provided between the IC tag antenna and the inner surface of the concave part of the lid main body part, it occurs around the antenna even if the IC tag antenna is arranged almost parallel to the front side surface part of the lid main body part. Since it is possible to prevent the magnetic flux to be absorbed from being absorbed by the lid main body portion and the occurrence of communication hindrance, it is possible to prevent the manhole lid from increasing in the thickness direction dimension.

  An object of the present invention is to provide a metal lid that can prevent communication inhibition of an IC tag and prevent an increase in dimension in the thickness direction, and a surface portion of a lid body portion of a manhole lid is recessed. This is achieved by forming a recess and mounting an IC tag housing portion that is formed of a rubber-based material and houses an IC tag in the recess.

Hereinafter, the present invention will be described in more detail with reference to the drawings and the like.
FIG. 1 is a front view showing a manhole cover which is an embodiment of the metal lid of the present invention. FIG. 2 is a perspective view showing an IC tag accommodating portion provided on the manhole cover of FIG. 3 is a cross-sectional view taken along the line AA of FIG. 1 and shows a state in which the IC tag housing portion of FIG. 2 is mounted in the concave portion of the lid main body portion.
The manhole cover 1 of the present embodiment is for closing an opening formed at an end portion on the ground side of a manhole which is a communication passage between an underground structure such as a common groove and the ground. The state where the opening is closed will be referred to as “during normal installation” of the manhole cover.

The manhole cover 1 includes a lid main body portion 10, a concave portion 11, an IC tag accommodating portion 20, and an IC tag 30.
The lid body 10 is a portion that is attached to the opening edge of the manhole when the manhole lid 1 is normally installed, and is formed into a disk shape by casting using an iron-based metal material. Here, the iron-based metal means, for example, pure iron and an alloy containing iron as a main component. In addition, when the manhole cover 1 is normally installed, the surface portion on the side of the lid main body 10 that appears on the ground surface is referred to as a “front surface portion”, and the opposite surface portion is referred to as a “back surface portion”.
The concave portion 11 is formed by denting a substantially central portion of the surface portion of the lid main body portion 10 into a cylindrical shape. On the other hand, as shown in FIG. 3, the substantially central portion of the back surface portion of the lid main body portion 10 has substantially the same thickness direction dimension as the portion where the concave portion 11 is formed and the other portions of the lid main body portion 10. Thus, it protrudes toward the underground side during normal installation.

As shown in FIG. 3, the IC tag accommodating portion 20 includes an accommodating main body portion 21 and a sealing portion 22.
The housing main body 21 is a molded product formed in a cylindrical shape with one end closed by a rubber-based material. The outer diameter of the housing main body 21 is smaller than the inner diameter of the recess 11. The rubber-based material forming the IC tag housing portion 20 is a nonmagnetic material having a lower magnetic permeability than the lid body portion 10.

The IC tag 30 is of an electromagnetic induction type using, for example, a 13.56 MHz frequency band, and includes an antenna 31 for transmission / reception thereof. The antenna 31 is a loop antenna formed by, for example, conductive ink being printed in a spiral shape on a base material formed in a circular sheet shape with a resin such as PET, and similarly on the base material. Are connected to an IC chip (not shown) disposed in This IC chip holds information such as a telephone line management number, which is arranged in a common groove where the manhole cover 1 is installed.
The IC tag 30 is housed in a space formed inside the housing body 21, and in a state in which the IC tag housing 20 shown in FIG. 11 is attached to the housing main body 21 with a double-sided tape (not shown).

The sealing portion 22 is formed of silicon resin or the like, and is provided by closing the opening of the housing main body 21. The silicon resin forming the sealed portion 22 is filled with the IC tag 30 in the housing main body 21 and then filled in the housing main body 21 in a paste state, and then cured, for example, by reacting with moisture in the air. Thus, the IC tag 30 is sealed in the IC tag accommodating portion 20. This silicon resin is also a nonmagnetic material like the housing body 21, and its magnetic permeability is smaller than that of the lid body 10.
Here, the lid body 10 is made of an iron-based metal, and is a ferromagnetic body having a relative permeability of approximately 1,000 or more, depending on the composition. On the other hand, the IC tag accommodating portion 20 (accommodating main body portion 21, sealing portion 22) is formed of a rubber-based material and a silicon resin, which are nonmagnetic materials, and the relative magnetic permeability thereof is approximately about 1. The relative magnetic permeability is a value obtained by dividing the magnetic permeability of a certain substance by the vacuum magnetic permeability. Since the vacuum magnetic permeability is constant, the IC tag accommodating portion 20 has a lower magnetic permeability than the lid main body portion 10. It functions as a magnetic permeability part.

The IC tag housing portion 20 is fitted and fitted into the recess 11 so that the end on the side filled with the sealing portion 22 faces the bottom surface of the recess 11 in the lid main body portion 10. As a result, the antenna 31 of the IC tag 30 is disposed substantially parallel to the surface portion of the lid body 10. The dimension in the height direction of the IC tag accommodating portion 20 is substantially the same as the dimension in the depth direction of the concave portion 11 described above, and the IC tag accommodating portion 20 in the state where the IC tag accommodating portion 20 is fitted in the concave portion 11. The surface portion on the surface exposed to the ground surface is substantially flush with the surface portion of the lid main body portion 10.
In a state where the IC tag housing portion 20 is mounted on the lid main body portion 10, the antenna 31 of the IC tag 30 is separated from the bottom surface portion and the inner side surface portion of the recess 11 by, for example, 20 mm or more.

The IC tag accommodation unit 20 includes a tool insertion unit 23.
The tool insertion portion 23 is an outer peripheral edge portion on the closed end portion side of the housing main body portion 21 and is formed so as to cut out a pair of corner portions of the housing main body portion 21 at positions opposed to the radial direction. . The tool insertion portion 23 forms an opening at the outer peripheral edge portion of the housing main body 21 in a state where the manhole cover 1 during normal installation is viewed from above. Further, the tool insertion portion 23 has a step formed by deeply cutting the inner portion of the housing main body 21 from the closed end portion side in the inner diameter direction. As shown in FIG. It is L-shaped.
When removing this IC tag accommodating part 20 from the lid body part 10, a pair of tools (not shown) formed in a hook shape are inserted into the tool insertion part 23. As a result, the hook-shaped portion of the tool is caught by the above-described stepped portion of the tool insertion portion 23, and the IC tag accommodating portion 20 is held by the tool. Thereafter, the IC tag accommodating portion 20 is pulled out from the lid main body portion 10 by operating this tool.

  The manhole cover 1 is installed in an opening of a manhole such as a common groove after the IC tag 30 is accommodated, and an embedded object provided in the common groove or the like between the IC tag 30 and a reader / writer device (not shown). The communication of the above-described information is performed by radio waves. Thereby, this buried object can be managed from the ground without a person entering the manhole.

As described above, according to this embodiment, the following effects can be obtained.
(1) By accommodating the IC tag 30 in the IC tag accommodating portion 20, the antenna 31 and the inner surface of the concave portion 11 of the lid main body portion 10 are, for example, approximately 20 mm or more, that is, the lid main body portion 10 communicates with the IC tag 30. Since the distance between the IC tag 30 and the reader / writer device is set at a distance that does not inhibit the propagation of the radio wave, the propagation of the communication radio wave between the IC tag 30 and the reader / writer device is not inhibited by the lid body 10.
(2) Since communication hindrance can be prevented regardless of the arrangement of the antenna 31, the IC tag 30 can be made substantially parallel to the surface portion of the lid main body portion 10, and the thickness direction dimension of the manhole lid 1 can be increased. Can be prevented.
(3) Since the IC tag accommodating portion 20 encloses and stores the IC tag 30, even if the manhole cover 1 is installed outdoors and directly exposed to rainwater or the like, Prevents water from entering.
(4) Since the IC tag accommodating portion 20 is detachable from the lid main body portion 10, for example, even when the IC tag 30 is damaged, the manhole lid 1 can be easily and without being removed from the manhole. The IC tag 30 can be replaced quickly.
(5) Since the IC tag accommodating portion 20 is formed of a rubber-based material, the IC tag accommodating portion 20 is provided with vibration absorption, and it is difficult to transmit vibration to the manhole cover 1 to the IC tag 30. Is prevented.

(Modification)
The present invention is not limited to the embodiments described above, and various modifications and changes are possible, and these are also within the equivalent scope of the present invention.
(1) In the embodiment, the lid main body has a disk shape, but is not limited thereto, and may have other shapes, for example, a rectangular plate shape.
(2) In the embodiment, the main body housing portion is formed of a rubber-based material. However, the present invention is not limited to this, and other materials that are non-magnetic materials may be used. For example, a resin-based material such as silicon resin May be formed.
(3) In the embodiment, the antenna is printed on a sheet material with a circular IC tag. However, the present invention is not limited to this, and the sheet material may have, for example, a rectangular shape or other shapes. In addition, the antenna of the IC tag may be other forms other than the loop antenna, such as a dipole antenna or a patch antenna.
(4) In the embodiment, the manhole cover is provided in an opening of an underground buried object such as a common groove, but the metal cover of the present invention is not limited to this, and other openings other than the manhole are provided. For example, it may be used as a lid of a box that accommodates a water meter for the purpose of managing the amount of water used.

It is a front view which shows the manhole cover of an Example. It is a perspective view which shows the IC tag accommodating part provided in the manhole cover of FIG. FIG. 3 is a cross-sectional view taken along the line A-A in FIG. 1 and shows a state in which the IC tag housing portion in FIG. 2 is mounted in the concave portion of the lid main body portion.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Manhole cover 10 Lid main-body part 11 Recessed part 20 IC tag accommodating part 21 Accommodating main-body part 22 Sealing part 30 IC tag 31 Antenna

Claims (5)

In a metal lid that holds an IC tag having an antenna therein,
A lid body formed of iron-based metal;
A concave portion that is formed by denting the front surface portion of the lid main body portion, and that the antenna is disposed substantially parallel to the front surface portion of the lid main body portion to accommodate the IC tag therein;
A metal lid, comprising: a low permeability portion provided between the antenna and the inner surface of the recess and made of a material having a smaller magnetic permeability than the lid body portion. The metal lid according to claim 1,
The metal lid, wherein the antenna is a loop antenna. In the metal lid according to claim 1 or 2,
The low magnetic permeability portion includes a molded product in which the IC tag is sealed. In the metal lid according to any one of claims 1 to 3,
A metal lid characterized in that the low magnetic permeability part can be attached to and detached from the lid body part. In the metal lid according to any one of claims 1 to 4,
The low magnetic permeability portion is formed of a rubber-based material.

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