JP3703724B2 - RFID tag communication method - Google Patents

Description

【００５１】
アンテナコイル２ａの一例としては、例えば、直径３０μｍ程度の銅線が単線巻きで径方向に多重層で軸方向にシリンダ状に巻かれており、そのアンテナコイル２ａの内部にコア部材３が有る状態でのインダクタンスは９．５mH（周波数１２５kHz）程度で、アンテナコイル２ａに共振用に別途接続されたコンデンサの静電容量は１７０pF（周波数１２５kHz）程度であった。
【００５２】
一方、導電性材料で作られた設置部材となる導電性部材５の表面５ａ側には表面を開放した断面方形状の設置溝部７が設けられており、ＲＦＩＤタグ１ａは該設置溝部７に挿入され、その軸方向（図２の左右方向）を該設置溝部７の設置面となる底面７ａと平行にして該底面７ａに略接するようにしてスペーサ等を介さずに直に設置される。
【００５３】
設置溝部７内に埋設されたＲＦＩＤタグ１ａのガラス容器６の外周には非導電性材料で作られた保護体となる樹脂８や接着剤等を充填して固定する。尚、設置溝部７内に埋設されたＲＦＩＤタグ１ａの外周に非導電性材料で作られたスポンジやガラスウール等の緩衝部材や断熱材をＲＦＩＤタグ１ａに接して設けても良い。
【００５４】
設置溝部７内に収納されたＲＦＩＤタグ１ａの表面側には保護体となる金属製等の導電性材料で作られた板体11が配置されてＲＦＩＤタグ１ａの表面側が覆われ、該板体11が固定手段となるビス10により導電性部材５に固定されている。
【００５５】
ＲＦＩＤタグ１ａの周囲を設置部材となる導電性部材５と保護体である板体11からなる導電性部材で覆った状態とし、該導電性部材５と板体11との接合面からなる磁束漏洩路12を通る漏洩磁束を利用して通信を行うように構成したものである。
【００５６】
図１に示すＲＦＩＤタグ１ａは、その本体が棒状に構成され、設置溝部７はＲＦＩＤタグ１ａの大きさに応じた方形状で構成されている。板体11は中央部に設置溝部７の形状に応じた形状を有する方形状の嵌合部11ａが設置溝部７側に突出しており、該嵌合部11ａを設置溝部７に嵌合することで位置決めがされ、板体11の鍔部11ｂに形成された貫通穴11ｃを介して導電性部材５に設けられたタップ穴５ｂにビス10を螺合締着することで板体11が導電性部材５に固定される。尚、導電性部材５にタップ穴５ｂを設けずにビス10としてタッピングビスを用いて固定しても良い。
【００５７】
また、ＲＦＩＤタグ１ａはガラス容器６の代わりに樹脂等で封止したものを更に非導電性材料からなる樹脂や接着剤等を充填して固定しても良い。
【００５８】
図５はフリーの状態のＲＦＩＤタグ１ａから発生する磁界Ｈの様子を示す。
【００５９】
ＲＦＩＤタグ１ａのアンテナコイル２ａの軸方向の端部と、ガラス容器６の軸方向の端部とは上記表１に示したＬ_１，Ｌ_２の寸法差に応じた位置関係にあり、図１及び図２に示す設置溝部７の側面７ｂと、アンテナコイル２ａの軸方向の端部との間に所定の離間間隔が形成され、これによりアンテナコイル２ａを貫く磁束が形成され易く、磁界Ｈの形成に寄与する。
【００６０】
また、図２（ａ）に示すように、ビス10により固定される導電性部材５と、保護体となる板体11との間には互いに当接する接触面が形成され、この接触面により磁束を漏洩させる磁束漏洩路12が形成される。
【００６１】
上記の磁束漏洩路12を形成するための間隙は、所望の漏洩磁束の大きさにより変化させ、例えばビス10の締付力または接触面の粗面の程度などによって調整される。粗面化により磁束漏洩路12を形成させる場合には、対向する両表面は互いに分散接触し、磁束漏洩路12は分散する非接触部分を利用して形成される。
【００６２】
接触面の表面粗度は、互いに対向する表面の一方の表面粗度が０．０４μｍ程度に加工され、これにより接触面の隙間として０．０８μｍ程度が形成され、所望の電磁波の漏洩度が確保される。
【００６３】
また、図２（ｂ）では、導電性部材５と、保護体となる板体11との間にゴムや樹脂等の非導電性材料で作られたスペーサ13を介在させて固定手段となるビス10により固定したもので、比較的大きな厚さの磁束漏洩路12が確保出来る。
【００６４】
保護体となる板体11と導電性部材５との間に非導電性材料からなるスペーサ13を介在させた場合には、密封性を確保しつつ、且つ導電性部材５と板体11との間に形成される非導電性材料により漏れ磁束が多くなるため好ましい。
【００６５】
また、図２（ｃ）では、導電性部材５と、保護体となる板体11とを、固定手段となる非導電性材料からなる接着剤14により固定したもので、接着による略平滑な接触面が形成され、この接触面により磁束を漏洩させる磁束漏洩路12が形成される。
【００６６】
また、保護体となる板体11を導電性部材５に対して接着剤14により固定した場合には、簡単な構成で固定出来、板体11と導電性部材５との間に介在する接着剤14の層により密封性を確保しつつ、且つ導電性部材５と板体11との間に非導電性材料からなる物理的な磁束漏洩路12が形成されるため漏れ磁束が多くなる。
【００６７】
尚、板体11と導電性部材５との間にスペーサ13を介在させて接着剤14により板体11とスペーサ13と導電性部材５とを接着しても良い。
【００６８】
本発明者等が行った実験結果によれば、磁界Ｈは狭い隙間であっても回析現象により狭い隙間から伝搬することが判明したものであり、上述のような物理的な僅かな隙間である磁束漏洩路12を実用的なレベルで送受信可能な量の磁束が漏洩し得るように形成し、それを検証することでＲＦＩＤタグ１ａと外部のリード端末機等との間で電力送電媒体及び情報通信媒体である交流磁界を相互に送受信することが出来ることを見い出したものである。
【００６９】
尚、磁束漏洩路12の経路長と該磁束漏洩路12の間隙幅（平均間隙幅）は外部のリードライト端末機等との間に電磁波の送信が可能な最低値以上有れば良く、０．０８μｍ程度の間隙幅（平均間隙幅）があれば十分である。
【００７０】
ＲＦＩＤタグ１ａの表面側を覆う保護体となる板体11が導電性材料で作られ、該板体11と導電性部材５との間に磁束漏洩路12が形成されたことで、外部からの応力や衝撃に対して一層強いものとなり、且つ磁束漏洩路12を介して電磁波が漏洩し、ＲＦＩＤタグ１ａと外部のリーダライタ端末機等との間で電力送電媒体及び情報通信媒体である交流磁界を相互に送受信することが出来る。
【００７１】
従って、ＲＦＩＤタグ１ａを導電性部材５に設けた表面側が開放された設置溝部７の底面７ａに略密着して直付けで設置し、更に設置溝部７の表面側を金属製等の導電性材料で作られた保護体となる板体11により覆っても図２（ａ）〜（ｃ）に示すように、導電性部材５の表面側に漏れ磁束による磁界Ｈが発生しており、磁束漏洩路12を通る漏洩磁束を利用して周囲を導電性部材５と導電性材料からなる板体11とにより覆われた状態のＲＦＩＤタグ１ａと外部のリーダライタ端末機等との間で通信が出来る。
【００７２】
図１の設置溝部７は保護体となる方形状の板体11に対応して断面方形状で形成した一例であるが、保護体として円盤状の板体11を用意し、該円盤状の板体11に対応して断面円形状の設置溝部７を形成することでも良い。
【００７３】
これ等は予め設置溝部７を想定して導電性部材５の形状を製作するか、図１の設置溝部７はドリル等で複数の穴を連続的に並設して断面方形状の設置溝部７を形成することも可能である。また、断面円形状の設置溝部７ではドリル等により容易に形成することが出来る。
【００７４】
また、アンテナコイル２ａにより形成される磁束の方向が、板体11と、導電性部材５との接合面と一致した方向（図２の左右方向）に配置されており、これにより漏れ磁束の回折現象による伝搬が効果的に出来、設置面の上部に形成される磁界Ｈの形成に寄与する。
【００７５】
上記構成によれば、ＲＦＩＤタグ１ａから出た磁束の一部が導電性部材５の設置面である底面７ａ上に分布し、それが磁気漏洩路12から外部に漏洩し、その漏洩磁束を利用して板体11の外部のリードライト端末機等と通信することが出来る。
【００７６】
また、リードライト端末機等の発信装置から出た磁束は磁束漏洩路12から保護体となる板体11で覆われた設置溝部７内に入り、その一部がＲＦＩＤタグ１ａのアンテナコイル２ａで検出される。
【００７７】
従って、ＲＦＩＤタグ１ａを導電性部材５に設置し、機械的強度の大きい金属等の導電性材料で作られた保護体となる板体11で保護した状態で外部と通信することが出来る。
【００７８】
また、導電性部材５に設置溝部７を形成し、その設置溝部７の底面７ａを設置面としてＲＦＩＤタグ１ａを配置したことで、ＲＦＩＤタグ１ａから出た磁束の一部、若しくはＲＦＩＤタグ１ａへ向かう磁束の一部は設置溝部７の空間に分布し、それを利用して磁束漏洩路12を通して通信することが出来る。
【００７９】
このようにすると、ＲＦＩＤタグ１ａ及び保護体となる板体11を設置溝部７から突出しないように設置出来る。
【００８０】
従って、従来のようにＲＦＩＤタグ１ａと導電性部材５との間に空間を確保したり非導電性材料を介在させることを排除して導電性部材５に形成する設置溝部７を浅くすることが出来、構成が簡単で別途、スペーサとして非導電性材料等を用意する必要もない。
【００８１】
また、導電性部材５に形成される設置溝部７の深さも小さくて済み、導電性部材５の強度を確保することが出来る。従って、導電性部材５が薄手の物に対してＲＦＩＤタグ１ａを設置する場合に有利である。
【００８２】
また、板体11によりＲＦＩＤタグ１ａを覆うことで該ＲＦＩＤタグ１ａの保全を確保することが出来、導電性部材５を有する製品に外力が作用して衝撃を受けてもＲＦＩＤタグ１ａが破損する等の虞が無い。
【００８３】
また、導電性部材５の設置溝部７や板体11の収納部15に緩衝部材や断熱材を介在させてＲＦＩＤタグ１ａを保護することで、より効果的にＲＦＩＤタグ１ａの保全を確保すると共に温度の安定化を図ることでＲＦＩＤタグ１ａの性能の安定化を図ることが出来る。
【００８４】
また、板体11はビス10や接着剤14で固定する以外にも、スライド式等で開閉可能なシャッター構造やヒンジ部材等を介して回動して開閉可能な構造としても良い。
【００８５】
図６（ａ）は、保護体となる板体11が設置溝部７側に突出した前記実施形態の嵌合部11ａを除去した平板からなるものであり、板体11が導電性部材５に対して直に当接され、固定手段となるビス10により固定された一例を示す。
【００８６】
尚、前記実施形態と同様に板体11と導電性部材５との間に非導電性材料からなるスペーサ13を介在させたり、接着剤14により板体11を導電性部材５に接着することでも良い。
【００８７】
図６（ｂ）は金属製等の導電性材料で作られた保護体となる板体11の中央部に導電性部材５の設置溝部７に対応して該設置溝部７と反対側に上方に突出した方形状の箱部11ｄが設けられており、該箱部11ｄの内部には設置溝部７に対向した収納部15が形成されている。本実施形態では、この収納部15にＲＦＩＤタグ１ａの一部が収納される。
【００８８】
そして、導電性部材５の設置溝部７と保護体となる板体11の収納部15の内部にＲＦＩＤタグ１ａを収納し、導電性部材５の設置溝部７側に板体11の収納部15を対向させた状態で該板体11を導電性部材５に固定してＲＦＩＤタグ１ａが覆われる。
【００８９】
即ち、本実施形態の板体11は、図６（ｂ）に示すように、ハット形状で構成されており、ハット形状の板体11が導電性部材５に対して直に当接され、ビス10により固定される。尚、前述と同様に、板体11と導電性部材５との間に非導電性材料からなるスペーサ13を介在させたり、接着剤14により板体11を導電性部材５に接着しても良い。
【００９０】
アンテナコイル２ａがシリンダ状に形成された棒状のＲＦＩＤタグ１ａでは、その軸方向（図６（ｂ）の左右方向）に磁力線が発生するため、図６（ｂ）に示すように、板体11と導電性部材５との接合部に形成された磁束漏洩路12の方向とＲＦＩＤタグ１ａの軸方向とが一致した場合に漏れ磁束がより効果的に回析現象により導電性部材５と板体11との接合部の狭い磁束漏洩路12を経由して伝搬することが出来、これにより、設置溝部７の設置面となる底面７ａの上方で磁界Ｈが形成され、ＲＦＩＤタグ１ａと図示しない外部のリーダライタ端末機等との間でより感度良く、電力送電媒体及び情報通信媒体である交流磁界を相互に送受信することが出来る。
【００９１】
尚、導電性部材５の設置面が平面状で、その上部にハット形状の板体11を固定しても良い。
【００９２】
尚、設置溝部７は保護体となる方形状の板体11に対応して断面方形状で形成しても良いが、保護体として円盤状の板体11を用意し、該円盤状の板体11に対応して断面円形状の設置溝部７を形成することでも良い。
【００９３】
また、図示しないが、導電性部材５の垂直面に断面方形状や断面円形状等の設置溝部７が形成され、該設置溝部７と、これに対向するハット形状の板体11の断面方形状或いは断面円形状の収納部15との内部にＲＦＩＤタグ１ａが、その軸方向を導電性部材５の垂直面と直交する方向で配置収納されても良い。
【００９４】
また、図示しないが、導電性部材５が平面状の垂直面で構成され、ＲＦＩＤタグ１ａを、その軸方向を導電性部材５の垂直面と直交する方向で収納部15に配置収納した状態でハット形状の板体11を該導電性部材５に固定しても良い。
【００９５】
尚、導電性部材５の表面は水平面や垂直面以外の傾斜面や或いは湾曲面であっても同様に適用出来るものである。
【００９６】
図７は保護体である平板状の板体11を貫通してシリンダ状に形成されたアンテナコイル２ａを有するＲＦＩＤタグ１ａの軸方向と一致する方向で該アンテナコイル２ａの長さＬ_２に応じた長さを有する磁束漏洩路となるスリット11ｅを設けたものである。
【００９７】
保護体である板体11に形成した磁束漏洩路となるスリット11ｅを介して漏れ磁束が回折して発生し、設置溝部７の設置面となる底面７ａの上部に磁界Ｈが形成される。これによりＲＦＩＤタグと外部のリーダライタ端末機等との間で電力送電媒体及び情報通信媒体である交流磁界を相互に送受信する効果をより向上することが出来る。
【００９８】
図８は開口部22を有する導電性材料で作られた容器本体21と、該開口部22を覆う導電性材料で作られた蓋体23により容器が構成され、この導電性材料で作られた容器内にＲＦＩＤタグ１ａを収容することで該ＲＦＩＤタグ１ａの周囲を容器からなる導電性部材で覆った状態とし、容器本体21と蓋体23との間の分割面からなる磁束漏洩路12を通る漏洩磁束を利用して通信を行うように構成したものである。
【００９９】
２分割された容器本体21の開口部22の内部に電磁誘導タグ１ａを収容して蓋体23を該容器本体21に接合して固定することで電磁誘導タグ１ａを覆って保護する。尚、容器は導電性材料で作られた他の複数の分割可能な分割体により多分割されたものを接合して電磁誘導タグ１ａの周囲を容器からなる導電性部材で覆った状態としても良い。
【０１００】
ＲＦＩＤタグ１ａは、容器本体21に設けられた開口部22に挿入して収容され、該開口部22の側面22ａ、底面22ｂに略密着してスペーサ等を介さずに直に設置されている。
【０１０１】
開口部22内に収納されたＲＦＩＤタグ１ａの外周には非導電性材料からなるスポンジやガラスウール等の衝撃緩衝材や断熱材が充填され、容器本体21に対してビス10により固定された蓋体23により開口部22を塞いでＲＦＩＤタグ１ａが覆われている。
【０１０２】
蓋体23は図８（ａ）に示すように、中央部に開口部22の形状に応じた形状を有する嵌合部23ａが開口部22側に突出しており、該嵌合部23ａを開口部22に嵌合することで位置決めがされ、蓋体23の鍔部23ｂに形成された貫通穴23ｃを介して容器本体21に設けられたタップ穴21ａにビス10を螺合締着することで蓋体23が容器本体21に固定される。
【０１０３】
本実施形態では、容器本体21と蓋体23との間にゴムや樹脂等の非導電性材料からなるスペーサ13を設けたものであるが容器本体21と蓋体23とを直接接合しても良いし、接着剤14により接合しても良い。金属部材11と金属部材５との間にゴムや樹脂等の非磁性体材料からなるスペーサ13を設けたものであり、尚、容器本体21にタップ穴21ａを設けずにビス10としてタッピングビスを用いて固定しても良い。
【０１０４】
容器本体21と蓋体23との間に非導電性材料からなるスペーサ13を介在させた場合には、密封性を確保しつつ、且つ容器本体21と蓋体23との間に形成されるスペーサ13により磁束漏洩路12の幅を調整出来、漏れ磁束が多くなるため好ましい。
【０１０５】
また、蓋体23を容器本体21に対して接着剤14により固定した場合には、簡単な構成で固定出来、蓋体23と容器本体21との間に介在する非導電性材料からなる接着剤14の層により密封性を確保しつつ、且つ容器本体21と蓋体23との間に磁束漏洩路12が形成されるため漏れ磁束が多くなる。これにより、電磁誘導タグ１ａと外部のリーダライタ端末機等の間で電力送電媒体及び情報通信媒体である交流磁界を相互に送受信する場合に有利である。
【０１０６】
また、容器本体21と、蓋体23との接合面の離間間隔は０．０８μｍ以上に設定されており、磁界Ｈの回折現象による伝搬が効果的に出来、これにより電力や信号の授受が可能になっている。
【０１０７】
また、アンテナコイル２ａにより形成される磁束の方向が、容器本体21と、蓋体23との接合面と一致した方向（図８の左右方向）に配置されており、これにより磁界Ｈの回折現象による伝搬が効果的に出来るため好ましい。
【０１０８】
図８（ｂ）は蓋体23が開口部22側に突出した嵌合部23ａを除去した平板からなるものであり、非導電性材料からなる接着剤14により蓋体23を容器本体21に接着したものである。尚、蓋体23が容器本体21に対して直に当接され、ビス10により固定されても良いし、蓋体23と容器本体21との間に非導電性材料からなるスペーサ13を介在させても良い。
【０１０９】
図９及び図10に示すシリンダ状のアンテナコイル２ａを有するＲＦＩＤタグ１ａは、保護体として金属製等の導電性材料で作られたキャップ体31ａの内部に収納され、樹脂８や接着剤等の封止材により封止されて固定されている。尚、キャップ体31ａ内に埋設されたＲＦＩＤタグ１ａに接して非導電性材料からなるスポンジやガラスウール等の緩衝部材や断熱材を配置しても良い。
【０１１０】
ＲＦＩＤタグ１ａを収納したキャップ体31ａは、該ＲＦＩＤタグ１ａを覆った状態で設置部材となる導電性部材５の設置溝部７の設置面となる底面７ａ側にキャップ体31ａの収納部を対向させた状態で該キャップ体31ａを設置溝部７内に装着して固定される。
【０１１１】
図10に示すキャップ体31ａは、ＲＦＩＤタグ１ａの大きさに応じた円筒形状の側板31a1と円盤形状の天板31a2を有して構成され、導電性部材５に形成された設置溝部７はキャップ体31ａの大きさに応じた円筒形状で構成されている。
【０１１２】
そして、キャップ体31ａの側面部と底面部、或いは導電性部材５の設置溝部７内に接着剤14が塗布された状態で、キャップ体31ａの天板31a2が導電性部材５の表面５ａ側に配置される向きで該キャップ体31ａが設置溝部７内に挿入され、接着剤14により接合されて固定される。
【０１１３】
図９にはキャップ体31ａの内部に収納され、該キャップ体31ａに覆われた状態で導電性部材５の設置溝部７の内部に埋設されたＲＦＩＤタグ１ａから発生する漏れ磁束により設置溝部７の設置面となる底面７ａ上に形成される磁界Ｈの様子を併せて図示したものである。
【０１１４】
ＲＦＩＤタグ１ａのアンテナコイル２ａの軸方向の端部と、キャップ体31ａの側板31a1の内壁面31a3との間には所定の離間間隔が形成され、これによりアンテナコイル２ａを貫く磁束が形成され易く、磁界Ｈの形成に寄与する。
【０１１５】
磁界Ｈは導電性部材５の設置溝部７とキャップ体31ａとの接合面に形成される磁束漏洩路12を通る漏れ磁束の回析現象により設置溝部７の設置面となる底面７ａの上部に伝搬することが出来、これにより、ＲＦＩＤタグ１ａと図示しない外部のリーダライタ端末機等との間で電力送電媒体及び情報通信媒体である交流磁界を相互に送受信することが出来るものである。
【０１１６】
ＲＦＩＤタグ１ａを導電性部材５の設置溝部７の底面７ａに略密着して設置し、更にキャップ体31ａにより上部を覆っても図９に示すように導電性部材５の設置溝部７の底面７ａ上部に磁界Ｈが発生している。
【０１１７】
尚、キャップ体31ａと導電性部材５との間に図示しないゴムや樹脂等の非導電性材料からなるスペーサを介在させて設けても良い。キャップ体31ａと導電性部材５との間に非導電性材料からなるスペーサを介在させた場合には、密封性を確保しつつ、且つ導電性部材５とキャップ体31ａとの間に形成される非導電性材料により漏れ磁束が多くなるため好ましい。
【０１１８】
また、キャップ体31ａと導電性部材５との間にスペーサを介在させた場合には、スペーサと導電性部材５及びスペーサとキャップ体31ａとの間に接着剤14を介在させて固定させても良い。
【０１１９】
また、キャップ体31ａを導電性部材５に対して接着剤14により固定した場合には、簡単な構成で固定出来、キャップ体31ａと導電性部材５との間に介在する接着剤14の層により密封性を確保しつつ、且つ導電性部材５とキャップ体31ａとの間に非導電性材料からなる磁束漏洩路12が形成されるため漏れ磁束が多くなる。これにより、ＲＦＩＤタグ１と外部のリーダライタ端末機等の間で電力送電媒体及び情報通信媒体である交流磁界を相互に送受信する場合に有利である。
【０１２０】
また、磁束漏洩路12は、キャップ体31ａと、導電性部材５との接合面の離間間隔が０．０８μｍ以上の隙間が確保されるように設定されており、これにより漏れ磁束の回折現象による伝搬が効果的に出来、設置溝部７の設置面となる底面７ａの上部に磁界Ｈが形成され、これにより電力や信号の授受が可能になっている。
【０１２１】
上記構成によれば、導電性部材５に形成される設置溝部７の深さも小さくて済み、導電性部材５の性能や強度を確保することが出来る。従って、導電性部材５が薄手の物に対してＲＦＩＤタグ１ａを設置する場合に有利である。
【０１２２】
従って、従来のようにＲＦＩＤタグ１ａと導電性部材５との間に空間を確保したり非導電性材料を介在させることを排除して導電性部材５に形成する設置溝部７を浅くすることが出来、構成が簡単で別途、スペーサとして非導電性材料等を用意する必要もない。
【０１２３】
また、キャップ体31ａによりＲＦＩＤタグ１ａを覆うことで該ＲＦＩＤタグ１ａの保全を確保することが出来、導電性部材５を有する製品に外力が作用して衝撃を受けてもＲＦＩＤタグ１ａが破損する等の虞が無い。
【０１２４】
また、キャップ体31ａの内部の収納部に緩衝部材や断熱材を介在させてＲＦＩＤタグ１ａを保護することで、より効果的にＲＦＩＤタグ１ａの保全を確保すると共に温度の安定化を図ることでＲＦＩＤタグ１ａの性能の安定化を図ることが出来る。
【０１２５】
尚、図示しないが、ＲＦＩＤタグ１ａの大きさに応じた方形状の側板と方形状の天板を有して構成された方形状のキャップ体を該キャップ体の大きさに応じた方形状で構成された設置溝部７内に挿入して接合することでも良い。
【０１２６】
図11及び図12に示す実施形態では、保護体となるキャップ体31ａの側板31a1の外壁面31a4にネジ部31a5が形成されており、該ネジ部31a5に対応して導電性部材５の設置溝部７の側面７ｂにネジ部7b1が形成されている。
【０１２７】
そして、キャップ体31ａの内部の収納部にＲＦＩＤタグ１ａを収納して樹脂８等の封止材により封止して固定した後、導電性部材５の設置溝部７の設置面となる側面７ｂ側にキャップ体31ａのＲＦＩＤタグ１ａを収納した収納部を対向させた状態で該キャップ体31ａのネジ部31a5を設置溝部７のネジ部7b1に螺合締着して該キャップ体31ａを設置溝部７内に装着固定する。
【０１２８】
尚、キャップ体31ａの天板31a2の上面には係合穴31a6が形成されており、図示しない締着治具を該係合穴31a6に係合させてキャップ体31ａを導電性部材５に螺合締着して固定することが出来るようになっている。
【０１２９】
本実施形態の場合、キャップ体31ａのネジ部31a5と設置溝部７のネジ部7b1との螺合により締着固定されるが、ネジ部7b1，31a5相互間の接合面の離間間隔が０．０８μｍ以上の隙間が確保されて磁束漏洩路12が形成されるため、該磁束漏洩路12を通して漏れ磁束が回折現象により伝播し、設置溝部７の設置面となる底面７ａの上部に磁界Ｈが形成される。これにより、外部のリードライト端末機等との間で電力や信号の授受が可能になっている。
【０１３０】
図13及び図14では、シリンダ状に形成されたアンテナコイル２の軸方向端部に対応するキャップ体31ａの側板31a1を切り欠いて漏れ磁束を増やすための磁束漏洩路を構成するスリット32を設けたものである。
【０１３１】
図14に示すキャップ体31ａの円筒形状の側板31a1には略半円形状のスリット32が形成された一例を示す。尚、方形状のキャップ体の方形状の側板に方形状のスリットを形成しても良いし、側板31a1から天板31a2にかけて連続したＬ字形状のスリットを形成しても良い。また、スリットの形状は漏れ磁束を増やすことが出来、且つ、キャップ体の強度を維持し得る程度の他の種々の形状、大きさで形成することが出来る。
【０１３２】
上記構成によれば、キャップ体31ａの側板31a1や天板31a2に形成した磁束漏洩路となるスリット32を介して漏れ磁束を更に増やすことが出来、このスリット32を介して漏れ磁束が回折して設置溝部７の設置面となる底面７ａの上部に磁界Ｈを形成することが出来、ＲＦＩＤタグ１ａと外部のリーダライタ端末機等との間で電力送電媒体及び情報通信媒体である交流磁界を相互に送受信する効果をより向上することが出来る。
【０１３３】
尚、ＲＦＩＤタグ１ａの保護体となる導電性材料で作られた板体11や容器本体21、蓋体23或いはキャップ体31ａ等の分割体自身にもスリット等の磁束漏洩路を形成しても良い。
【０１３４】
図15及び図16において、41はノート型パソコンであり、外装が導電性部材となる金属ケースにより覆われている。ノート型パソコン41はキーボード41a1が設けられた導電性材料で作られた本体側41ａと、液晶ディスプレイ41b1が設けられた導電性材料で作られた蓋側41ｂとが分割体容器として構成され、開閉手段であって回動軸となるヒンジ部材41ｃを介して回動して互いに開閉可能に連結されている。
【０１３５】
ノート型パソコン41は、図16（ｂ）に示すように、本体側41ａと蓋側41ｂとが互いの面41a2，41b2を対向して閉じられ、且つ蓋側41ｂが本体側41ａに対して開放出来る物品の一例であるが、他に同様な構造の携帯情報端末機(モバイルパソコン)や携帯電話機等各種の物品の製品管理にも適用可能である。
【０１３６】
ノート型パソコン41の蓋側41ｂの面41b2と、本体側41ａの面41a2との間には、ＲＦＩＤタグ１ａが配置されている。ＲＦＩＤタグ１ａのメモリ４ｂに、例えば、ＲＦＩＤタグ１ａが設けられるノート型パソコン41の履歴データやロット管理データ等が記憶されている。尚、ＲＦＩＤタグ１ａにノート型パソコン41の固有のコード情報が記憶されており、その固有のコード情報をリードライト端末機等により読み出して別のデータベースから履歴データやロット管理データ等を閲覧することも可能である。
【０１３７】
本実施形態では、蓋側41ｂの面41b2にＲＦＩＤタグ１ａが非導電性材料からなる接着材や粘着材等により固定され、本体側41ａの面41a2のＲＦＩＤタグ１ａに応じた部位に該ＲＦＩＤタグ１ａの大きさに応じた凹部41a3が形成されている。
【０１３８】
そして、図16（ａ）に示すように本体側41ａの面41a2と、蓋側41ｂの面41b2との間に形成される微小な隙間である磁束漏洩路12から発生する漏れ磁束により形成される磁界Ｈを利用してＲＦＩＤタグ１ａに記憶された情報を図示しないリードライト端末機等により取り出すことが出来る。
【０１３９】
本体側41ａの面41a2と、蓋側41ｂの面41b2とにより形成される微小な隙間である磁束漏洩路12がＲＦＩＤタグ１ａのアンテナコイル２ａの軸方向に開放した状態で形成されるため、これによりアンテナコイル２ａを貫く磁束が形成され易く、磁界Ｈの形成に寄与する。
【０１４０】
磁界Ｈは本体側41ａの面41a2と、蓋側41ｂの面41b2とにより形成される微小な隙間である磁束漏洩路12から伝搬することが出来、その磁束漏洩路12から発生する漏れ磁束により、ＲＦＩＤタグ１ａと図示しない外部のリードライト端末機等との間で電力送電媒体及び情報通信媒体である交流磁界を相互に送受信してＲＦＩＤタグ１ａに記憶された情報を取り出すことが出来るものである。
【０１４１】
従って、外装が金属ケースからなるノート型パソコンや携帯情報端末機（モバイルパソコン）、携帯電話機等、一方を開放して見開きに出来るこれ等と同様の形態を有する各種の物品において、一方と他方との間にＲＦＩＤタグ１ａを配置し、該ＲＦＩＤタグ１ａに記憶された情報を取り出すことで製品管理を行うことが出来る。
【０１４２】
従って、梱包された製品を再検査する場合でも梱包材の外側からＲＦＩＤタグａに記憶された情報を取り出すことが出来、一旦梱包された製品の梱包材を解く必要がないため、作業性が良い。
【０１４３】
図17（ａ）は参考例としてＲＦＩＤタグの通信方法を鋼板を複数重ねたものに適用した場合の一例を示す側面説明図、図17（ｂ）は図17（ａ）の斜視説明図である。
【０１４４】
図17（ａ），（ｂ）において、板状とされた複数の導電性部材となる平板状の鋼板51が当て木52を介して複数枚積み重ねられており、各鋼板51の表面にはＲＦＩＤタグ１ａが設置され、鋼板51と鋼板51との間に磁束漏洩路12が形成され、該磁束漏洩路12を通る漏洩磁束を利用してＲＦＩＤタグ１ａと積み重ねられた鋼板51の外部との間で通信を行うように構成されている。
【０１４５】
ＲＦＩＤタグ１ａは鋼板51に対して非導電性材料からなる接着材や粘着材等で固定されても良いし、ＲＦＩＤタグ１ａを保持する磁石を鋼板51に吸着させても良い。
【０１４６】
ＲＦＩＤタグ１ａは、図17（ｂ）に示すように、積載された鋼板51の角部に、その軸方向が斜め（例えば４５度）に傾けた状態で配置して固定されるのが好ましく、鋼板51と鋼板51との間に形成される隙間からなる磁束漏洩路12がＲＦＩＤタグ１ａのアンテナコイル２ａの軸方向に開放した状態で形成されるため、これによりアンテナコイル２ａを貫く磁束が形成され易く、磁界Ｈの形成に寄与する。
【０１４７】
磁界Ｈは鋼板51と鋼板51とにより形成される隙間により形成される磁束漏洩路12から伝搬することが出来、その磁束漏洩路12から発生する漏れ磁束により、ＲＦＩＤタグ１ａと図示しない外部のリードライト端末機等との間で電力送電媒体及び情報通信媒体である交流磁界を相互に送受信してＲＦＩＤタグ１ａに記憶された情報を取り出すことが出来るものである。
【０１４８】
尚、平板状の鋼板51以外にも緩やかに湾曲した湾曲板や波板にも同様に適用出来るものであり、複数枚重ねられた板状の導電性部材としては、鋼板51の代りに、例えば、銅箔により電気回路が形成されたプリント基板や、アルミニウム材、銅材、ステンレス材等の各種金属材料からなる他の種々の板状の金属物品や、樹脂、セメント、コンクリート等に鉄粉等の磁性体を混練した材料や、粉等の磁性体を布等に折り込んだり付着させた材料や、磁石等の磁性体からなる板状の物品を複数重ね合わせた場合に適用可能であり、これ等の板状の物品を複数重ねた状態で、該物品の間にＲＦＩＤタグ１ａを配置し、該ＲＦＩＤタグ１ａに記憶された情報を取り出すことで製品管理や在庫管理等を容易に且つ効率的に行うことが出来る。
【０１４９】
次に、参考例として図18〜図23を用いて同心円盤状のアンテナコイル２ｂを有するＲＦＩＤタグ１ｂの通信方法について説明する。尚、前記シリンダ状のアンテナコイル２ａを有するＲＦＩＤタグ１ａと同様の構成については同一の符号を付して説明を省略する。
【０１５０】
図18は導電性部材の設置溝部に配置された同心円盤状のアンテナコイルを有するＲＦＩＤタグを一部が該設置溝部内に挿入される凸部を有する板状の保護体により覆う様子を示す分解説明図、図19は図18の板状の保護体を固定手段により導電性部材に固定した様子を示す断面説明図である。
【０１５１】
また、図20は同心円盤状のアンテナコイルを有するＲＦＩＤタグの構成を示す正面及び側面説明図、図21は同心円盤状のアンテナコイルを有するＲＦＩＤタグに発生する磁界の様子を示す模式図である。
【０１５２】
また、図22は導電性部材の設置溝部に配置されたＲＦＩＤタグを平坦な板状の保護体により覆う様子を示す断面説明図、図23は板状の保護体に各種のスリットを形成した場合の一例を示す分解説明図である。
【０１５３】
図18〜図23に示すＲＦＩＤタグ１ｂも同心円盤状のアンテナコイル２ｂと、制御部となる半導体ＩＣチップ４とがプリント回路基板等を介さずに直結して一体的に形成されており、これによりＲＦＩＤタグ１ｂの小型化を実現している。尚、ＲＦＩＤタグ１ｂの制御系の構成は図４に示して前述したと同様である。
【０１５４】
図20に示すＲＦＩＤタグ１ｂの内部には、単線巻きで径方向に多重層をなして同心円盤状に巻かれて形成されたアンテナコイル２ｂ、半導体ＩＣチップ４等が一体的に樹脂61により封止されて全体が円盤状に構成されている。
【０１５５】
ＲＦＩＤタグ１ｂはアンテナコイル２ｂの径方向の外径Ｄ_４に応じた外径Ｄ_３を有する樹脂61により封止されている。
【０１５６】
以下に本参考例で採用したＲＦＩＤタグ１ｂの樹脂61の外径Ｄ_３、及びアンテナコイル２ｂの外径Ｄ_４及びアンテナコイル２ｂの内径Ｄ_５の一例を示す。
【０１５７】
【表２】

【０１５８】
また、ＲＦＩＤタグ１ｂの樹脂61の厚さＴは０．７mm〜１２．０mm程度であり、ＲＦＩＤタグ１ｂの重量は、０．７g〜５．２g程度である。
【０１５９】
アンテナコイル２ｂの一例としては、直径３０μｍ程度の銅線が単線巻きで径方向に多重層をなして同心円盤状に巻かれており、そのアンテナコイル２ｂのインダクタンスは９．５mH（周波数１２５kHz）程度で、アンテナコイル２ｂに共振用に別途接続されたコンデンサの静電容量は１７０pF（周波数１２５kHz）程度であった。
【０１６０】
図21はフリーの状態のＲＦＩＤタグ１ｂから発生する磁界Ｈの様子を示す。
【０１６１】
一方、導電性部材５にはＲＦＩＤタグ１ｂの大きさに応じた断面円形状の設置溝部７が形成されており、ＲＦＩＤタグ１ｂが、そのアンテナコイル面を導電性部材５の設置面となる底面７ａに平行にして配置し、該導電性部材５と、金属製等の導電性材料で作られた保護体となる板体11との間に磁束漏洩路12が形成される。
【０１６２】
図18及び図19に示す保護体となる板体11は中央部に設置溝部７の形状に応じた形状を有する円柱形状の嵌合部11ａが設置溝部７側に突出しており、該嵌合部11ａを設置溝部７に嵌合することで位置決めがされ、板体11の鍔部11ｂに形成された貫通穴11ｃを介して導電性部材５に設けられたタップ穴５ｂに固定手段となるビス10を螺合締着することで板体11が導電性部材５に固定される。尚、導電性部材５にタップ穴５ｂを設けずにビス10としてタッピングビスを用いて固定しても良い。
【０１６３】
尚、ＲＦＩＤタグ１ｂも樹脂61の代わりにガラス容器に封止されたものでも良い。また、ＲＦＩＤタグ１ｂを可撓性の合成樹脂等により封止してＲＦＩＤタグ１ｂの本体自体が緩衝部材を兼ねるように構成したものであっても良い。
【０１６４】
尚、図19には導電性部材５の設置溝部７の内部に埋設されたＲＦＩＤタグ１ｂから発生する磁界Ｈの様子を併せて図示したものである。
【０１６５】
図22（ａ），（ｂ）は、保護体となる板体11が平板からなるものであり、図22（ａ）では板体11が導電性部材５に対して直に当接され、固定手段となるビス10により固定された一例を示す。
【０１６６】
また、図22（ｂ）では導電性部材５の設置溝部７の上部表面側に段部５ｃが形成され、該段部５ｃに平板からなる板体11が嵌合されたものであり、板体11の表面と導電性部材５の表面とが略面一になって突出を無くしたものである。
【０１６７】
図23（ａ）は円盤状の板体11を貫通して同心円盤状に形成されたアンテナコイル２ｂを有するＲＦＩＤタグ１ｂの径方向と一致する方向でアンテナコイル２ｂの中心に対応する部位から放射状にアンテナコイル２ｂの外径Ｄ_４に応じた長さを有するスリット11ｅを磁束漏洩路として設けたものである。尚、スリット11ｅは接着剤や充填材で閉鎖することも出来る。
【０１６８】
また、図23（ｂ）はアンテナコイル２ｂの径方向に磁束漏洩路として１本だけスリット11ｅを設けたものである。尚、スリット11ｅは接着剤や充填材で閉鎖することも出来る。
【０１６９】
同心円盤状のアンテナコイル２ｂを有するＲＦＩＤタグ１ｂから発生した漏れ磁束は磁束漏洩路12や磁束漏洩路となるスリット11ｅを通して回折現象により導電性部材５の設置面となる底面７ａの上部に磁界Ｈを形成し、外部のリードライト端末機等との間で電力送電媒体及び情報通信媒体である交流磁界を相互に送受信することが出来る。
【０１７０】
尚、前述の板体11やキャップ体31ａは導電性部材５に対してビス止め接合や接着剤接合により固定する以外にも嵌め合い接合、カシメ接合、ネジ嵌合接合、シーム接合、粘着材接合により磁束漏洩路を実用的なレベルで送受信可能な量の磁束が漏洩し得るように固定することでも良い。シーム結合とは金属板同士の間に高密度ポリエチレン等を介して接合部位を共巻きにして接合されたものである。
【０１７１】
【発明の効果】
本発明は、上述の如き構成と作用とを有するので、ＲＦＩＤタグの周囲を導電性部材で覆った状態であっても該導電性部材に形成した磁束漏洩路を通る漏洩磁束を利用してＲＦＩＤタグと導電性部材の外部との間で通信を行うことが出来る。
【０１７２】
また、ＲＦＩＤタグを導電性材料で作られた設置部材に設置し、該ＲＦＩＤタグの表面側を導電性材料で作られた保護体で覆うことによって、該ＲＦＩＤタグの周囲を設置部材と保護体からなる導電性部材で覆った状態としても該設置部材と該保護体の間、或いは該保護体の少なくとも一方に形成した磁束漏洩路を通る漏洩磁束を利用して通信を行うことが出来る。
【０１７３】
また、導電性材料で作られた容器内にＲＦＩＤタグを収容することによって該ＲＦＩＤタグの周囲を容器からなる導電性部材で覆った状態としても該容器に設けた磁束漏洩路を通る漏洩磁束を利用して通信を行うことが出来る。
【０１７４】
また、シリンダ状のアンテナコイルを有し、棒状に形成されたＲＦＩＤタグは、極めて小型化出来るので導電性部材に許容される設置面積が小さい場合でも容易に設置出来る。
【図面の簡単な説明】
【図１】 導電性部材の設置溝部に配置されたＲＦＩＤタグを一部が該設置溝部内に挿入される凸部を有する板状の保護体により覆う様子を示す分解説明図である。
【図２】 図１の板状の保護体を各種の固定手段により導電性部材に固定した様子を示す断面説明図である。
【図３】 シリンダ状のアンテナコイルを有するＲＦＩＤタグの構成を示す正面説明図である。
【図４】 ＲＦＩＤタグの制御系の構成を示すブロック図である。
【図５】 シリンダ状のアンテナコイルを有するＲＦＩＤタグに発生する磁界の様子を示す模式図である。
【図６】 （ａ）は導電性部材の設置溝部に配置されたＲＦＩＤタグを平坦な板状の保護体により覆う様子を示す断面説明図、（ｂ）は導電性部材の設置溝部に配置されたＲＦＩＤタグを、該ＲＦＩＤタグの一部を収納する収納部を形成した板状の保護体により覆う様子を示す断面説明図である。
【図７】 板状の保護体に直線状のスリットを形成した場合の一例を示す分解説明図である。
【図８】 開口部を有する容器本体内に収納したＲＦＩＤタグを、その開口部を覆う蓋体により覆った様子を示す断面説明図である。
【図９】 導電性部材の設置溝部に配置されたＲＦＩＤタグを、該ＲＦＩＤタグを収納する収納部を形成したキャップ体からなる保護体により覆う様子を示す断面説明図である。
【図10】 設置溝部及びキャップ体が断面円形状に構成された場合の一例を示す分解説明図である。
【図11】 固定手段の一例としてネジ止めによりキャップ体からなる保護体を導電性部材の設置溝部内に装着した様子を示す断面説明図及び分解説明図である。
【図12】 固定手段の一例としてネジ止めによりキャップ体からなる保護体を導電性部材の設置溝部内に装着した様子を示す断面説明図及び分解説明図である。
【図13】 キャップ体からなる保護体のシリンダ状アンテナコイルの軸方向に切り欠きを設けた様子を示す断面説明図である。
【図14】 断面円形状のキャップ体からなる保護体のシリンダ状アンテナコイルの軸方向に切り欠きを設けた様子を示す分解説明図である。
【図15】 本発明に係るＲＦＩＤタグの通信方法をノート型パーソナルコンピュータに適用した場合の一例を示す斜視説明図である。
【図16】 （ａ）は本発明に係るＲＦＩＤタグの通信方法をノート型パソコンに適用した場合の一例を示す平面説明図、（ｂ）は本発明に係るＲＦＩＤタグの通信方法をノート型パソコンに適用した場合の一例を示す側面説明図である。
【図17】 （ａ）は参考例としてＲＦＩＤタグの通信方法を鋼板を複数重ねたものに適用した場合の一例を示す側面説明図、（ｂ）は参考例としてＲＦＩＤタグの通信方法を鋼板を複数重ねたものに適用した場合の一例を示す斜視説明図である。
【図18】 導電性部材の設置溝部に配置された同心円盤状のアンテナコイルを有するＲＦＩＤタグを一部が該設置溝部内に挿入される凸部を有する板状の保護体により覆う様子を示す分解説明図である。
【図19】 図18の板状の保護体を固定手段により導電性部材に固定した様子を示す断面説明図である。
【図20】 同心円盤状のアンテナコイルを有するＲＦＩＤタグの構成を示す正面及び側面説明図である。
【図21】 同心円盤状のアンテナコイルを有するＲＦＩＤタグに発生する磁界の様子を示す模式図である。
【図22】 導電性部材の設置溝部に配置されたＲＦＩＤタグを平坦な板状の保護体により覆う様子を示す断面説明図である。
【図23】 板状の保護体に各種のスリットを形成した場合の一例を示す分解説明図である。
【符号の説明】
１ａ，１ｂ…ＲＦＩＤタグ
２ａ，２ｂ…アンテナコイル
３…コア部材
４…半導体ＩＣチップ
４ａ…ＣＰＵ
４ｂ…メモリ
４ｃ…送受信機
４ｄ…コンデンサ
５…導電性部材
５ａ…表面
５ｂ…タップ穴
５ｃ…段部
６…ガラス容器
７…設置溝部
７ａ…底面
７ｂ…側面
7b1…ネジ部
８…樹脂
10…ビス
11…板体
11ａ…嵌合部
11ｂ…鍔部
11ｃ…貫通穴
11ｄ…箱部
11ｅ…スリット
12…磁束漏洩路
13…スペーサ
14…接着剤
15…収納部
21…容器本体
21ａ…タップ穴
22…開口部
22ａ…側面
22ｂ…底面
23…蓋体
23ａ…嵌合部
23ｂ…鍔部
23ｃ…貫通穴
31ａ…キャップ体
31a1…側板
31a2…天板
31a3…内壁面
31a4…外壁面
31a5…ネジ部
31a6…係合穴
32…スリット
41…ノート型パソコン
41ａ…本体側
41a1…キーボード
41a2…面
41a3…凹部
41ｂ…蓋側
41b1…液晶ディスプレイ
41b2…面
41ｃ…ヒンジ部材
51…鋼板
52…当て木
61…樹脂[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a communication method of an RFID tag having an antenna coil and a control unit.
[0002]
[Prior art]
Conventionally, RFID tags (Radio Frequency IDentification TAGs) are classified into an electromagnetic induction type and an electromagnetic coupling type, and both use non-contact communication with a read / write terminal using an electromagnetic wave.
[0003]
The RFID tag has an antenna coil and a control unit, and when the antenna coil receives a transmission signal from the read / write terminal, the control unit accumulates it in the capacitor as power, and stores the power in the storage unit. The information such as the ID code is transmitted from the antenna coil to the read / write terminal again.
[0004]
As a transmission / reception method, there are an ASK (Amplitude Shift Keying) method and an FSK (Frequency Shift Keying) method. The former performs transmission / reception by amplitude shift modulation of electromagnetic waves, and the latter performs transmission / reception by frequency modulation of electromagnetic waves.
[0005]
When a general RFID tag is divided into antenna coil types, a disk-shaped antenna coil using a circular air-core coil and a cylinder-shaped antenna coil in which an insulation-coated copper wire such as an enameled wire is wound around a rod-shaped ferrite core. There are various types, and the outer shape is formed in a disk shape corresponding to the shape of each antenna coil, and the latter is formed in a bar shape.
[0006]
An RFID tag having a disk-shaped antenna coil performs communication using a change in magnetic flux in the surface direction of a circular coil, and an RFID tag having a cylindrical antenna coil performs communication using a change in magnetic flux in the axial direction. .
[0007]
By the way, an electromagnetic wave propagates an alternating electric field and a magnetic field with a phase of 90 degrees. When an alternating magnetic flux due to the magnetic field change intersects with a conductive member such as iron, aluminum, or copper, the conductive member enters the conductive member. An eddy current is generated, and a magnetic flux is generated in a direction that cancels the alternating magnetic field by the eddy current.
[0008]
For this reason, conventionally, the RFID tag has been generally installed and communicated as far away from the conductive member as possible.
[0009]
Moreover, in order to protect the surface side of the installed RFID tag from external forces such as impact, it is desirable to cover the surface side with a protective body made of a conductive material such as a metal having a high mechanical strength. By doing so, since the protector becomes a barrier when communicating with the read / write terminal or the like from the outside, communication is performed in a state covered with a protector made of a non-conductive material such as plastic.
[0010]
Also, in order to protect the RFID tag from external stress and impact in storing, transporting and using it, the surrounding area is often covered with a container or the like, but made of a conductive material for the same reason as above. Communication is performed in a state where an RFID tag is accommodated in a container made of a non-conductive material such as plastic without using the container.
[0011]
[Problems to be solved by the invention]
However, in the above-described conventional example, the protector or container using a non-conductive material such as plastic has a problem in durability because the resistance against external force is not so great. For example, when an RFID tag is installed in an installation groove provided on the lid of a metal manhole and the surface side is covered with a plastic protective body, the protective body is destroyed due to the load of a vehicle or the like passing over the RFID tag. There is a risk of tag damage.
[0012]
Also, when RFID tags housed in plastic containers are attached to a large number of steel plates for individual management, the steel plates tend to fall, collapse, collapse, etc. during transportation and storage, and the plastic containers are damaged and stored by the impact. There is a great risk of damage to the RFID tag.
[0013]
The present invention solves the above-mentioned problems, and its object is to provide a method for enabling communication of an RFID tag whose periphery is covered with a conductive member such as metal. .
[0014]
[Means for Solving the Problems]
The present inventors have formed a magnetic flux leakage path by a gap or the like in a part of the conductive member even when the periphery of the RFID tag is covered with a conductive member such as metal. The present invention has been completed on the basis of the new knowledge that communication is possible.
[0015]
That is, when communication is performed between an RFID tag and a read / write terminal using electromagnetic waves, the sensitivity of the device greatly affects the sensitivity of the device. The level of sensitivity has increased considerably, and practical communication is possible even with a small amount of magnetic flux.
[0016]
Based on such technical background, the present inventors have conducted various research and experiments. As a result, when the periphery of the RFID tag is covered with a conductive member, a part of the magnetic flux used for communication is a conductive member. However, some magnetic flux can exist in the space confined by the conductive member, and if a magnetic flux leakage path is provided in the conductive member, a part of the magnetic flux existing in the space It was found that it leaked to the outside through the magnetic flux leakage path.
[0017]
It has been found that communication at a practical level is possible using the leakage magnetic flux.
[0018]
In order to achieve the above object, an RFID tag communication method according to the present invention includes a cylindrical antenna coil and a control unit, and the entire RFID tag formed in a rod shape is covered with a conductive member. A method of communicating in a state, wherein the conductive member includes an RFID tag and the conductive member. External communication To do Enables leakage of magnetic flux leakage A magnetic flux leakage path consisting of a gap is formed. The magnetic flux leakage path extends from the vicinity of the tip of the RFID tag inside the conductive member to the outside of the conductive member, and the leakage magnetic flux passing through the magnetic flux leakage path is used. Then, communication is performed between the RFID tag and the outside of the conductive member.
[0019]
According to the above communication method, even when the periphery of the RFID tag is covered with the conductive member, the leakage flux passing through the magnetic flux leakage path formed in the conductive member is used to connect the RFID tag and the outside of the conductive member. Can communicate with each other.
[0020]
In addition, an installation groove portion is provided in an installation member made of a conductive material, and the RFID tag is installed in the installation groove portion. At this time, the RFID tag is arranged in parallel to the bottom surface of the installation groove portion, and the RFID tag The surface of the RFID tag is covered with a protective body made of a conductive material, so that the installation member and the protective body are covered even when the periphery of the RFID tag is covered with a conductive member made of the installation member and the protective body. It is possible to communicate between the RFID tag and the outside of the protector using leakage magnetic flux passing through a magnetic flux leakage path formed between the RFID tag and the outside of the protective body.
[0021]
Further, even when the RFID tag is accommodated in a container made of a conductive material and the periphery of the RFID tag is covered with a conductive member made of the container, leakage through the magnetic flux leakage path provided in the container Communication can be performed using magnetic flux.
[0022]
Further, the container can be constituted by a plurality of division bodies that can be divided, and a magnetic flux leakage path can be formed on the division surface.
[0023]
Moreover, a container can also be comprised with the container main body which has an opening part, and the cover body which covers the opening part.
[0024]
Further, the divided bodies can be connected to each other by an opening / closing means so as to be opened and closed.
[0025]
Moreover, it is preferable when the antenna coil is formed in a cylinder shape. In particular, an RFID tag having a cylindrical antenna coil and formed in a rod shape can be extremely miniaturized, so that it can be easily installed even when the installation area allowed for the conductive member is small.
[0026]
DETAILED DESCRIPTION OF THE INVENTION
Each embodiment of the RFID tag communication method according to the present invention will be described in detail with reference to the drawings. 1 to 17 are diagrams illustrating a communication method of an RFID tag having a cylindrical antenna coil, and FIGS. 18 to 23 illustrate a communication method of an RFID tag having a concentric disk-shaped antenna coil as a reference example. FIG.
[0027]
First, a communication method of an RFID tag having a cylindrical antenna coil will be described with reference to FIGS. FIG. 1 is an exploded explanatory view showing a state in which a part of an RFID tag arranged in an installation groove portion of a conductive member is covered with a plate-shaped protective body having a convex portion inserted into the installation groove portion, and FIG. It is sectional explanatory drawing which shows a mode that the plate-shaped protection body of this was fixed to the electroconductive member with the various fixing means.
[0028]
3 is a front explanatory view showing a configuration of an RFID tag having a cylindrical antenna coil, FIG. 4 is a block diagram showing a configuration of a control system of the RFID tag, and FIG. 5 is an RFID tag having a cylindrical antenna coil. It is a schematic diagram which shows the mode of the magnetic field to generate | occur | produce.
[0029]
6A is a cross-sectional explanatory view showing a state where the RFID tag arranged in the installation groove portion of the conductive member is covered with a flat plate-shaped protective body, and FIG. 6B is a diagram showing the installation groove portion of the conductive member. It is sectional explanatory drawing which shows a mode that the RFID tag arrange | positioned is covered with the plate-shaped protector in which the accommodating part which accommodates a part of this RFID tag was formed.
[0030]
FIG. 7 is an exploded explanatory view showing an example in which a linear slit is formed in a plate-shaped protective body, and FIG. 8 is a diagram showing an RFID tag housed in a container body having an opening with a lid that covers the opening. It is sectional explanatory drawing which shows a mode that it covered.
[0031]
FIG. 9 is an explanatory cross-sectional view showing a state in which the RFID tag arranged in the installation groove portion of the conductive member is covered with a protective body made of a cap body in which a storage portion for storing the RFID tag is formed, and FIG. 10 is an installation groove portion. FIG. 4 is an exploded explanatory view showing an example when the cap body is configured to have a circular cross section.
[0032]
11 and 12 are a cross-sectional explanatory view and an exploded explanatory view showing a state in which a protective body made of a cap body is mounted in the installation groove portion of the conductive member by screwing as an example of the fixing means.
[0033]
FIG. 13 is an explanatory cross-sectional view showing a state in which a cutout is provided in the axial direction of a cylindrical antenna coil of a protective body made of a cap body, and FIG. 14 is a cylindrical antenna coil of the protective body made of a cap body having a circular cross section. It is decomposition | disassembly explanatory drawing which shows a mode that the notch was provided in the axial direction.
[0034]
15 is a perspective explanatory view showing an example in which the RFID tag communication method according to the present invention is applied to a notebook personal computer (hereinafter simply referred to as “notebook personal computer”), and FIG. 16 is an RFID according to the present invention. It is plane explanatory drawing and a side explanatory drawing which show an example at the time of applying the communication method of a tag to a notebook type personal computer.
[0035]
FIG. 17 (a) is a side explanatory view showing an example in which the RFID tag communication method is applied to a plurality of stacked steel plates as a reference example, and FIG. 17 (b) is an RFID tag communication method using a steel plate as a reference example. It is perspective explanatory drawing which shows an example at the time of applying to what was piled up two or more.
[0036]
The RFID tags 1a and 1b that are preferably employed in the following are electromagnetic coupling type and electromagnetic induction type RFID tags. In each of the following embodiments, an embodiment using an electromagnetic induction type RFID tag will be described below. Explained.
[0037]
The RFID tag 1a shown in FIGS. 1 to 17 is integrally formed by directly connecting a cylindrical antenna coil 2a and a semiconductor IC chip 4 serving as a control unit without using a printed circuit board or the like. Thus, the RFID tag 1a can be downsized.
[0038]
A cylindrical core member 3 such as an iron core or ferrite is inserted in the axial direction (left and right direction in FIG. 3) inside the antenna coil 2a formed in a cylindrical shape by winding a single wire, and the antenna coil 2a and the core member 3 are inserted. The semiconductor IC chip 4 and the like are integrally formed so as to have a rod shape as a whole.
[0039]
The semiconductor IC chip 4 is formed by integrally packaging an IC (semiconductor integrated circuit) chip, an LSI (semiconductor large-scale integrated circuit) chip or the like. As shown, a CPU 4a serving as a control unit, a memory 4b serving as a storage unit, a transceiver 4c, and a capacitor 4d serving as a power storage unit are provided.
[0040]
A signal transmitted from an unillustrated external reader / writer terminal or the like is transmitted to the CPU 4a via the transceiver 4c, and the electric power is stored in the capacitor 4d. The capacitor 4d serving as the power storage means may be omitted, and power may be continuously supplied to the semiconductor IC chip 4 from an external reader / writer terminal.
[0041]
The CPU 4a is a central processing unit, and reads programs and various data stored in the memory 4b, performs necessary calculations and determinations, and performs various controls.
[0042]
The memory 4b stores various information such as various programs for operating the CPU 4a and history data and lot management data regarding products and parts including the conductive member 5 on which the RFID tags 1a and 1b are installed.
[0043]
The RFID tags 1a and 1b use a radio communication method of amplitude shift keying (ASK) with a radio frequency of one wave, an air core or a core member 3 having a wide resonance frequency band and a wire diameter of several tens of microns. RFID tags 1a and 1b using a CMOS-IC with very little power consumption and incorporating special transmission / reception circuits with antenna coils 2a and 2b are employed.
[0044]
The RFID tags 1a and 1b use an amplitude shift keying (ASK) wireless communication system. By using such an ASK system, there is very little risk of a frequency shift due to the influence of the conductive member as in the FSK system, a decrease in received power or a disturbance in the communication signal, and a magnetic flux leakage path. It becomes possible to communicate stably with the leakage flux from 12.
[0045]
Furthermore, according to the results of experiments conducted by the present inventors, it has been found that the magnetic field H propagates from a narrow gap due to diffraction phenomenon even in a narrow gap, and a predetermined slight gap is formed. Thus, it has been found that an AC magnetic field, which is a power transmission medium and an information communication medium, can be transmitted and received between the RFID tags 1a and 1b and an external reader / writer terminal or the like.
[0046]
In addition, as a conductive material that affects the communication by generating an eddy current due to the magnetic field H generated when the RFID tags 1a and 1b communicate and carry power, an eddy current is generated to attenuate the original magnetic flux. In addition to stainless steel plate, copper plate, aluminum plate, iron, cobalt, nickel and alloys thereof, ferromagnetic metals such as ferrite, or paramagnetic metals such as aluminum, copper, chrome, etc. Plastic or the like is applicable.
[0047]
As shown in FIG. 3, the RFID tag 1a has an outer diameter D in the radial direction of the antenna coil 2a. ₂ Outer diameter D according to ₁ The entire circumference is covered with a glass container 6 made of a glass material which is a non-conductive material having a slag.
[0048]
The length L in the axial direction of the glass container 6 of the RFID tag 1a employed in this embodiment. ₁ Is about 7 mm to 15.7 mm and the outer diameter D ₁ Is about 2.12 mm to 4.12 mm. Accordingly, the installation groove portion 7 of the conductive member 5 has a length L of the RFID tag 1a. ₁ And outer diameter D ₁ It is formed in the size according to. The RFID tag 1a has a weight of about 55 mg to 400 mg.
[0049]
The length L in the axial direction of the glass container 6 of the RFID tag 1a employed in the present embodiment is described below. ₁ , Outer diameter D ₁ , And the axial length L of the antenna coil 2a ₂ , Outer diameter D ₂ An example is shown.
[0050]
[Table 1]

[0051]
As an example of the antenna coil 2a, for example, a state in which a copper wire having a diameter of about 30 μm is wound in a cylindrical shape in the axial direction with multiple layers in the radial direction by single wire winding, and the core member 3 is inside the antenna coil 2a In this case, the inductance was about 9.5 mH (frequency 125 kHz), and the capacitance of the capacitor separately connected to the antenna coil 2a for resonance was about 170 pF (frequency 125 kHz).
[0052]
On the other hand, on the surface 5a side of the conductive member 5 serving as an installation member made of a conductive material, an installation groove portion 7 having a rectangular cross section with an open surface is provided, and the RFID tag 1a is inserted into the installation groove portion 7 Then, the axial direction (the left-right direction in FIG. 2) is parallel to the bottom surface 7a serving as the installation surface of the installation groove portion 7, and is installed directly without a spacer or the like so as to be substantially in contact with the bottom surface 7a.
[0053]
The outer periphery of the glass container 6 of the RFID tag 1a embedded in the installation groove 7 is filled and fixed with a resin 8 or an adhesive serving as a protector made of a non-conductive material. In addition, you may provide buffer members and heat insulating materials, such as sponge and glass wool made from a nonelectroconductive material, in contact with the RFID tag 1a on the outer periphery of the RFID tag 1a embedded in the installation groove portion 7.
[0054]
A plate body 11 made of a conductive material such as a metal serving as a protector is disposed on the surface side of the RFID tag 1a housed in the installation groove portion 7 so that the surface side of the RFID tag 1a is covered. 11 is fixed to the conductive member 5 by screws 10 as fixing means.
[0055]
Magnetic flux leakage consisting of a joint surface between the conductive member 5 and the plate body 11 in a state where the periphery of the RFID tag 1a is covered with a conductive member 5 comprising a conductive member 5 as an installation member and a plate body 11 as a protective body. Communication is performed using leakage magnetic flux passing through the path 12.
[0056]
The RFID tag 1a shown in FIG. 1 has a main body configured in a bar shape, and the installation groove portion 7 is configured in a square shape corresponding to the size of the RFID tag 1a. The plate body 11 has a square fitting portion 11 a having a shape corresponding to the shape of the installation groove portion 7 at the center portion protruding toward the installation groove portion 7, and by fitting the fitting portion 11 a to the installation groove portion 7. The plate body 11 is electrically conductive by positioning and screwing and fastening the screw 10 to the tap hole 5b provided in the conductive member 5 through the through hole 11c formed in the flange portion 11b of the plate body 11. 5 is fixed. The conductive member 5 may be fixed using a tapping screw as the screw 10 without providing the tap hole 5b.
[0057]
In addition, the RFID tag 1a may be fixed by sealing a resin or the like instead of the glass container 6 with a resin or an adhesive made of a non-conductive material.
[0058]
FIG. 5 shows a state of the magnetic field H generated from the RFID tag 1a in a free state.
[0059]
The axial end of the antenna coil 2a of the RFID tag 1a and the axial end of the glass container 6 are shown in Table 1 above. ₁ , L ₂ 1 and FIG. 2, a predetermined spacing is formed between the side surface 7b of the installation groove 7 shown in FIGS. 1 and 2 and the axial end of the antenna coil 2a. A magnetic flux penetrating the coil 2a is easily formed and contributes to the formation of the magnetic field H.
[0060]
Further, as shown in FIG. 2A, a contact surface that is in contact with each other is formed between the conductive member 5 fixed by the screw 10 and the plate body 11 serving as a protective body, and the contact surface forms a magnetic flux. A magnetic flux leakage path 12 is formed to leak.
[0061]
The gap for forming the magnetic flux leakage path 12 is changed according to the desired magnitude of the leakage magnetic flux, and is adjusted by, for example, the tightening force of the screw 10 or the degree of roughness of the contact surface. When the magnetic flux leakage path 12 is formed by roughening, both opposing surfaces are in dispersed contact with each other, and the magnetic flux leakage path 12 is formed using a non-contact portion that is dispersed.
[0062]
The surface roughness of the contact surface is processed so that one of the surfaces facing each other has a surface roughness of about 0.04 μm, thereby forming a clearance of about 0.08 μm as a gap between the contact surfaces, thereby ensuring the desired electromagnetic wave leakage. Is done.
[0063]
In FIG. 2B, a screw serving as a fixing means by interposing a spacer 13 made of a non-conductive material such as rubber or resin between the conductive member 5 and the plate 11 serving as a protective body. A fixed magnetic flux leakage path 12 having a relatively large thickness can be secured.
[0064]
When a spacer 13 made of a non-conductive material is interposed between the plate 11 serving as a protective body and the conductive member 5, the sealing between the conductive member 5 and the plate 11 is ensured while ensuring sealing performance. The non-conductive material formed therebetween is preferable because the leakage magnetic flux increases.
[0065]
In FIG. 2 (c), the conductive member 5 and the plate 11 serving as a protective body are fixed by an adhesive 14 made of a non-conductive material serving as a fixing means. A surface is formed, and a magnetic flux leakage path 12 for leaking magnetic flux is formed by this contact surface.
[0066]
In addition, when the plate 11 serving as a protective body is fixed to the conductive member 5 with the adhesive 14, it can be fixed with a simple configuration, and the adhesive interposed between the plate 11 and the conductive member 5. Since the physical flux leakage path 12 made of a non-conductive material is formed between the conductive member 5 and the plate 11 while securing the sealing performance by the 14 layers, the leakage magnetic flux increases.
[0067]
Alternatively, the spacers 13 may be interposed between the plate body 11 and the conductive member 5, and the plate body 11, the spacer 13, and the conductive member 5 may be bonded by the adhesive 14.
[0068]
According to the results of experiments conducted by the present inventors, it has been found that the magnetic field H propagates from the narrow gap due to the diffraction phenomenon even in a narrow gap. A magnetic flux leakage path 12 is formed so that an amount of magnetic flux that can be transmitted and received at a practical level can be leaked, and by verifying it, an electric power transmission medium between the RFID tag 1a and an external lead terminal and the like It has been found that an AC magnetic field, which is an information communication medium, can be transmitted and received mutually.
[0069]
The path length of the magnetic flux leakage path 12 and the gap width (average gap width) of the magnetic flux leakage path 12 need only be equal to or greater than the minimum value at which electromagnetic waves can be transmitted to an external read / write terminal or the like. A gap width (average gap width) of about .08 μm is sufficient.
[0070]
A plate body 11 serving as a protector covering the surface side of the RFID tag 1a is made of a conductive material, and a magnetic flux leakage path 12 is formed between the plate body 11 and the conductive member 5, so that an external An AC magnetic field that is stronger against stress and impact, leaks electromagnetic waves through the magnetic flux leakage path 12, and is an electric power transmission medium and information communication medium between the RFID tag 1a and an external reader / writer terminal. Can be sent and received between each other.
[0071]
Accordingly, the RFID tag 1a is installed on the conductive member 5 by directly attaching the RFID tag 1a to the bottom surface 7a of the installation groove 7 whose surface side is open, and the surface of the installation groove 7 is made of a conductive material such as metal. 2A to 2C, a magnetic field H due to leakage magnetic flux is generated on the surface side of the conductive member 5, and the magnetic flux leakage is caused. Communication is possible between the RFID tag 1a and the external reader / writer terminal or the like whose surroundings are covered with the conductive member 5 and the plate 11 made of a conductive material by utilizing the leakage magnetic flux passing through the path 12. .
[0072]
The installation groove 7 in FIG. 1 is an example formed in a square cross section corresponding to the square plate 11 serving as a protector, but a disc-like plate 11 is prepared as a protector, and the disc-like plate is prepared. The installation groove portion 7 having a circular cross section may be formed corresponding to the body 11.
[0073]
In this case, the shape of the conductive member 5 is manufactured assuming the installation groove portion 7 in advance, or the installation groove portion 7 of FIG. It is also possible to form Further, the installation groove portion 7 having a circular cross section can be easily formed by a drill or the like.
[0074]
Further, the direction of the magnetic flux formed by the antenna coil 2a is arranged in a direction (left and right direction in FIG. 2) that coincides with the joint surface between the plate 11 and the conductive member 5, thereby diffracting the leakage magnetic flux. Propagation due to the phenomenon can be effectively performed, which contributes to the formation of the magnetic field H formed on the upper surface of the installation surface.
[0075]
According to the above configuration, a part of the magnetic flux emitted from the RFID tag 1a is distributed on the bottom surface 7a which is the installation surface of the conductive member 5, which leaks to the outside from the magnetic leakage path 12, and uses the leakage magnetic flux. Thus, communication with a read / write terminal or the like outside the plate 11 is possible.
[0076]
Further, the magnetic flux emitted from a transmitting device such as a read / write terminal enters the installation groove portion 7 covered with the plate 11 serving as a protector from the magnetic flux leakage path 12, and a part thereof is the antenna coil 2a of the RFID tag 1a. Detected.
[0077]
Therefore, it is possible to communicate with the outside in a state where the RFID tag 1a is installed on the conductive member 5 and protected by the plate 11 which is a protective body made of a conductive material such as a metal having high mechanical strength.
[0078]
In addition, the installation groove portion 7 is formed in the conductive member 5, and the RFID tag 1a is disposed with the bottom surface 7a of the installation groove portion 7 as the installation surface, so that a part of the magnetic flux emitted from the RFID tag 1a or the RFID tag 1a. Part of the magnetic flux heading is distributed in the space of the installation groove 7 and can be used to communicate through the magnetic flux leakage path 12.
[0079]
In this way, the RFID tag 1a and the plate 11 serving as a protective body can be installed so as not to protrude from the installation groove portion 7.
[0080]
Therefore, it is possible to make the installation groove portion 7 formed in the conductive member 5 shallower by eliminating a space between the RFID tag 1a and the conductive member 5 as in the prior art or by interposing a nonconductive material. The structure is simple and there is no need to separately prepare a non-conductive material or the like as a spacer.
[0081]
Moreover, the depth of the installation groove part 7 formed in the electroconductive member 5 may be small, and the intensity | strength of the electroconductive member 5 can be ensured. Therefore, the conductive member 5 is advantageous when the RFID tag 1a is installed on a thin object.
[0082]
Further, the RFID tag 1a can be secured by covering the RFID tag 1a with the plate body 11, and the RFID tag 1a is damaged even when an external force is applied to the product having the conductive member 5 to receive an impact. There is no fear of such.
[0083]
Further, by protecting the RFID tag 1a by interposing a buffer member or a heat insulating material in the installation groove portion 7 of the conductive member 5 or the storage portion 15 of the plate body 11, the RFID tag 1a can be more effectively maintained. By stabilizing the temperature, the performance of the RFID tag 1a can be stabilized.
[0084]
Further, the plate body 11 may have a shutter structure that can be opened and closed by a slide type or a structure that can be rotated and opened via a hinge member or the like, in addition to being fixed by the screw 10 or the adhesive 14.
[0085]
FIG. 6A shows a flat plate from which the plate 11 serving as a protection body has been removed from the fitting portion 11 a of the above-described embodiment protruding toward the installation groove 7, and the plate 11 is in contact with the conductive member 5. An example in which the screw 10 is directly contacted and fixed by a screw 10 serving as a fixing means is shown.
[0086]
As in the above-described embodiment, a spacer 13 made of a nonconductive material is interposed between the plate 11 and the conductive member 5 or the plate 11 is bonded to the conductive member 5 with an adhesive 14. good.
[0087]
FIG. 6B shows a plate 11 which is a protective body made of a conductive material such as a metal, and is located upward on the opposite side of the installation groove 7 corresponding to the installation groove 7 of the conductive member 5. A protruding rectangular box portion 11d is provided, and a storage portion 15 facing the installation groove portion 7 is formed inside the box portion 11d. In the present embodiment, a part of the RFID tag 1a is stored in the storage unit 15.
[0088]
Then, the RFID tag 1a is housed inside the installation groove portion 7 of the conductive member 5 and the storage portion 15 of the plate body 11 serving as a protector, and the storage portion 15 of the plate body 11 is placed on the installation groove portion 7 side of the conductive member 5. In a state of being opposed to each other, the plate body 11 is fixed to the conductive member 5 to cover the RFID tag 1a.
[0089]
That is, as shown in FIG. 6B, the plate body 11 of the present embodiment is configured in a hat shape, and the hat-shaped plate body 11 is brought into direct contact with the conductive member 5 and is screwed. Fixed by 10. As described above, a spacer 13 made of a nonconductive material may be interposed between the plate 11 and the conductive member 5, or the plate 11 may be bonded to the conductive member 5 with an adhesive 14. .
[0090]
In the rod-shaped RFID tag 1a in which the antenna coil 2a is formed in a cylinder shape, magnetic lines of force are generated in the axial direction (the left-right direction in FIG. 6B), and as shown in FIG. When the direction of the magnetic flux leakage path 12 formed at the junction between the conductive member 5 and the conductive member 5 coincides with the axial direction of the RFID tag 1a, the leakage magnetic flux is more effectively diffracted by the diffraction phenomenon. 11 can be propagated via a narrow magnetic flux leakage path 12 at the junction with 11, whereby a magnetic field H is formed above the bottom surface 7 a serving as an installation surface of the installation groove 7, and the RFID tag 1 a and an external not shown The AC magnetic field, which is a power transmission medium and an information communication medium, can be transmitted and received between the reader / writer terminals and the like with higher sensitivity.
[0091]
Note that the conductive member 5 may have a flat installation surface, and a hat-shaped plate 11 may be fixed to the upper surface thereof.
[0092]
The installation groove 7 may be formed in a square cross section corresponding to the rectangular plate 11 serving as a protective body. However, a disk-shaped plate 11 is prepared as the protective body, and the disk-shaped plate body is prepared. The installation groove portion 7 having a circular cross section may be formed corresponding to 11.
[0093]
Further, although not shown, an installation groove portion 7 having a cross-sectional square shape or a circular cross-sectional shape is formed on the vertical surface of the conductive member 5, and the cross-sectional square shape of the installation groove portion 7 and the hat-shaped plate body 11 facing the installation groove portion 7. Alternatively, the RFID tag 1 a may be disposed and housed in the direction perpendicular to the vertical plane of the conductive member 5 in the housing section 15 having a circular cross section.
[0094]
Although not shown, the conductive member 5 is configured by a flat vertical surface, and the RFID tag 1a is disposed and stored in the storage unit 15 with its axial direction orthogonal to the vertical surface of the conductive member 5. A hat-shaped plate 11 may be fixed to the conductive member 5.
[0095]
The surface of the conductive member 5 can be similarly applied even if it is an inclined surface other than a horizontal surface or a vertical surface, or a curved surface.
[0096]
FIG. 7 shows a length L of the antenna coil 2a in a direction coinciding with the axial direction of the RFID tag 1a having the antenna coil 2a formed in a cylindrical shape through the flat plate body 11 serving as a protective body. ₂ Is provided with a slit 11e serving as a magnetic flux leakage path having a length corresponding to the above.
[0097]
Leakage magnetic flux is diffracted and generated through a slit 11e serving as a magnetic flux leakage path formed on the plate 11 serving as a protector, and a magnetic field H is formed on the upper surface of the bottom surface 7a serving as the installation surface of the installation groove 7. Accordingly, it is possible to further improve the effect of transmitting and receiving the AC magnetic field, which is a power transmission medium and an information communication medium, between the RFID tag and an external reader / writer terminal.
[0098]
FIG. 8 shows a container composed of a container body 21 made of a conductive material having an opening 22 and a lid body 23 made of a conductive material covering the opening 22, and made of this conductive material. By accommodating the RFID tag 1a in a container, the periphery of the RFID tag 1a is covered with a conductive member made of a container, and a magnetic flux leakage path 12 formed of a split surface between the container main body 21 and the lid 23 is formed. Communication is performed using leakage magnetic flux passing through.
[0099]
The electromagnetic induction tag 1a is accommodated in the opening 22 of the container body 21 divided into two parts, and the lid body 23 is joined and fixed to the container body 21 to cover and protect the electromagnetic induction tag 1a. The container may be a state in which a plurality of divided parts made of a conductive material are joined together and the periphery of the electromagnetic induction tag 1a is covered with a conductive member made of the container. .
[0100]
The RFID tag 1a is inserted into and accommodated in an opening 22 provided in the container main body 21, and is placed in close contact with the side surface 22a and the bottom surface 22b of the opening 22 directly without a spacer or the like.
[0101]
The outer periphery of the RFID tag 1a accommodated in the opening 22 is filled with an impact cushioning material or heat insulating material such as sponge or glass wool made of a non-conductive material, and is fixed to the container body 21 with screws 10 The RFID tag 1a is covered by closing the opening 22 with the body 23.
[0102]
As shown in FIG. 8 (a), the lid 23 has a fitting portion 23a having a shape corresponding to the shape of the opening 22 at the center and protrudes toward the opening 22, and the fitting 23a is opened to the opening. 22 is positioned by fitting, and the screw 10 is screwed and fastened to the tap hole 21a provided in the container body 21 through the through hole 23c formed in the flange 23b of the lid 23. The body 23 is fixed to the container body 21.
[0103]
In this embodiment, a spacer 13 made of a non-conductive material such as rubber or resin is provided between the container body 21 and the lid body 23, but the container body 21 and the lid body 23 may be directly joined. It may be good or may be joined by the adhesive 14. A spacer 13 made of a non-magnetic material such as rubber or resin is provided between the metal member 11 and the metal member 5, and a tapping screw is provided as a screw 10 without providing a tap hole 21a in the container body 21. It may be used and fixed.
[0104]
When a spacer 13 made of a non-conductive material is interposed between the container body 21 and the lid body 23, a spacer formed between the container body 21 and the lid body 23 while ensuring sealing performance 13 is preferable because the width of the magnetic flux leakage path 12 can be adjusted and the leakage magnetic flux increases.
[0105]
Further, when the lid 23 is fixed to the container main body 21 with the adhesive 14, the adhesive can be fixed with a simple configuration, and is made of a non-conductive material interposed between the lid 23 and the container main body 21. Since the magnetic flux leakage path 12 is formed between the container main body 21 and the lid body 23 while ensuring the sealing performance by the 14 layers, the leakage magnetic flux increases. This is advantageous when the AC magnetic field, which is a power transmission medium and an information communication medium, is mutually transmitted and received between the electromagnetic induction tag 1a and an external reader / writer terminal.
[0106]
In addition, the separation distance between the joint surface of the container body 21 and the lid body 23 is set to 0.08 μm or more, so that propagation due to the diffraction phenomenon of the magnetic field H can be effectively performed, and thus power and signals can be exchanged. It has become.
[0107]
Further, the direction of the magnetic flux formed by the antenna coil 2a is arranged in the direction (left and right direction in FIG. 8) that coincides with the joint surface between the container main body 21 and the lid 23, and thereby the diffraction phenomenon of the magnetic field H. This is preferable because propagation due to can be effectively performed.
[0108]
FIG. 8B shows a case in which the lid body 23 is made of a flat plate from which the fitting portion 23a protruding to the opening 22 side is removed, and the lid body 23 is bonded to the container body 21 with an adhesive 14 made of a non-conductive material. It is a thing. The lid body 23 may be directly abutted against the container body 21 and fixed with screws 10, or a spacer 13 made of a non-conductive material may be interposed between the lid body 23 and the container body 21. May be.
[0109]
An RFID tag 1a having a cylindrical antenna coil 2a shown in FIGS. 9 and 10 is housed in a cap body 31a made of a conductive material such as metal as a protective body, and is made of resin 8 or adhesive. It is sealed and fixed with a sealing material. Note that a buffer member such as a sponge or glass wool made of a non-conductive material or a heat insulating material may be disposed in contact with the RFID tag 1a embedded in the cap body 31a.
[0110]
The cap body 31a in which the RFID tag 1a is housed has the housing portion of the cap body 31a opposed to the bottom surface 7a side which is the installation surface of the installation groove portion 7 of the conductive member 5 which is the installation member in a state of covering the RFID tag 1a. In this state, the cap body 31a is mounted in the installation groove portion 7 and fixed.
[0111]
A cap body 31a shown in FIG. 10 includes a cylindrical side plate 31a1 and a disk-shaped top plate 31a2 corresponding to the size of the RFID tag 1a, and the installation groove portion 7 formed on the conductive member 5 is a cap. It is comprised by the cylindrical shape according to the magnitude | size of the body 31a.
[0112]
Then, the top plate 31a2 of the cap body 31a is placed on the surface 5a side of the conductive member 5 in a state where the adhesive 14 is applied to the side surface and the bottom surface portion of the cap body 31a or the installation groove portion 7 of the conductive member 5. The cap body 31a is inserted into the installation groove portion 7 in the direction in which it is arranged, and is joined and fixed by the adhesive 14.
[0113]
In FIG. 9, the installation groove portion 7 is accommodated in the installation groove portion 7 by leakage magnetic flux generated from the RFID tag 1 a embedded in the installation groove portion 7 of the conductive member 5 while being stored in the cap body 31 a. The state of the magnetic field H formed on the bottom surface 7a serving as the installation surface is also illustrated.
[0114]
A predetermined separation interval is formed between the axial end of the antenna coil 2a of the RFID tag 1a and the inner wall surface 31a3 of the side plate 31a1 of the cap body 31a, whereby a magnetic flux penetrating the antenna coil 2a is easily formed. This contributes to the formation of the magnetic field H.
[0115]
The magnetic field H propagates to the upper part of the bottom surface 7a which becomes the installation surface of the installation groove 7 by the diffraction phenomenon of the leakage magnetic flux passing through the magnetic flux leakage path 12 formed on the joint surface between the installation groove 7 of the conductive member 5 and the cap body 31a. Accordingly, an AC magnetic field, which is a power transmission medium and an information communication medium, can be transmitted and received between the RFID tag 1a and an external reader / writer terminal (not shown).
[0116]
Even if the RFID tag 1a is installed in close contact with the bottom surface 7a of the installation groove portion 7 of the conductive member 5 and further covered with the cap body 31a, the bottom surface 7a of the installation groove portion 7 of the conductive member 5 as shown in FIG. A magnetic field H is generated at the top.
[0117]
Note that a spacer made of a nonconductive material such as rubber or resin (not shown) may be interposed between the cap body 31a and the conductive member 5. When a spacer made of a nonconductive material is interposed between the cap body 31a and the conductive member 5, it is formed between the conductive member 5 and the cap body 31a while ensuring sealing performance. The non-conductive material is preferable because the leakage magnetic flux increases.
[0118]
Further, when a spacer is interposed between the cap body 31a and the conductive member 5, the adhesive 14 may be interposed and fixed between the spacer, the conductive member 5, and the spacer and the cap body 31a. good.
[0119]
In addition, when the cap body 31a is fixed to the conductive member 5 with the adhesive 14, the cap body 31a can be fixed with a simple configuration, and the adhesive layer 14 interposed between the cap body 31a and the conductive member 5 can be used. Leakage magnetic flux increases because the magnetic flux leakage path 12 made of a nonconductive material is formed between the conductive member 5 and the cap body 31a while ensuring the sealing performance. This is advantageous when the AC magnetic field, which is a power transmission medium and an information communication medium, is mutually transmitted and received between the RFID tag 1 and an external reader / writer terminal.
[0120]
Further, the magnetic flux leakage path 12 is set so that a clearance of 0.08 μm or more is secured between the cap body 31a and the conductive member 5 so that a gap of 0.08 μm or more is secured. Propagation can be effectively performed, and a magnetic field H is formed on the upper surface of the bottom surface 7a, which is the installation surface of the installation groove portion 7, thereby enabling transmission and reception of electric power and signals.
[0121]
According to the said structure, the depth of the installation groove part 7 formed in the electroconductive member 5 may be small, and the performance and intensity | strength of the electroconductive member 5 can be ensured. Therefore, the conductive member 5 is advantageous when the RFID tag 1a is installed on a thin object.
[0122]
Therefore, it is possible to make the installation groove portion 7 formed in the conductive member 5 shallower by eliminating a space between the RFID tag 1a and the conductive member 5 as in the prior art or by interposing a nonconductive material. The structure is simple and there is no need to separately prepare a non-conductive material or the like as a spacer.
[0123]
Further, the RFID tag 1a can be protected by covering the RFID tag 1a with the cap body 31a, and the RFID tag 1a is damaged even when an external force acts on the product having the conductive member 5 and receives an impact. There is no fear of such.
[0124]
Further, by protecting the RFID tag 1a by interposing a buffer member or a heat insulating material in the storage portion inside the cap body 31a, it is possible to more effectively secure the RFID tag 1a and stabilize the temperature. It is possible to stabilize the performance of the RFID tag 1a.
[0125]
Although not shown, a rectangular cap body having a rectangular side plate corresponding to the size of the RFID tag 1a and a rectangular top plate has a rectangular shape corresponding to the size of the cap body. It may be inserted into the installed installation groove 7 and joined.
[0126]
In the embodiment shown in FIGS. 11 and 12, a screw portion 31a5 is formed on the outer wall surface 31a4 of the side plate 31a1 of the cap body 31a serving as a protector, and the installation groove portion of the conductive member 5 corresponding to the screw portion 31a5. 7 is formed with a threaded portion 7b1.
[0127]
Then, after the RFID tag 1a is housed in the housing portion inside the cap body 31a and sealed with a sealing material such as the resin 8 and fixed, the side surface 7b side that becomes the installation surface of the installation groove portion 7 of the conductive member 5 is provided. The cap 31a is screwed and fastened to the screw 7b1 of the installation groove 7 with the housing 31 storing the RFID tag 1a of the cap 31a facing the cap, and the installation groove 7 Install and fix inside.
[0128]
An engagement hole 31a6 is formed on the top surface of the top plate 31a2 of the cap body 31a. A fastening jig (not shown) is engaged with the engagement hole 31a6, and the cap body 31a is screwed onto the conductive member 5. It can be fixed by fastening.
[0129]
In the case of this embodiment, the screw 31a5 of the cap body 31a and the screw 7b1 of the installation groove 7 are fastened and fixed, but the spacing between the joint surfaces between the screws 7b1 and 31a5 is 0.08 μm. Since the above gap is secured and the magnetic flux leakage path 12 is formed, the leakage magnetic flux propagates through the magnetic flux leakage path 12 by a diffraction phenomenon, and the magnetic field H is formed on the upper surface of the bottom surface 7a which is the installation surface of the installation groove portion 7. The As a result, power and signals can be exchanged with an external read / write terminal or the like.
[0130]
13 and 14, a slit 32 is provided that forms a magnetic flux leakage path for cutting out the side plate 31a1 of the cap body 31a corresponding to the axial end of the antenna coil 2 formed in a cylinder shape to increase the leakage magnetic flux. It is a thing.
[0131]
An example in which a substantially semicircular slit 32 is formed in the cylindrical side plate 31a1 of the cap body 31a shown in FIG. A rectangular slit may be formed in the rectangular side plate of the rectangular cap body, or a continuous L-shaped slit may be formed from the side plate 31a1 to the top plate 31a2. The slit shape can be formed in various other shapes and sizes that can increase the leakage magnetic flux and maintain the strength of the cap body.
[0132]
According to the above configuration, the leakage magnetic flux can be further increased through the slit 32 serving as the magnetic flux leakage path formed in the side plate 31a1 and the top plate 31a2 of the cap body 31a, and the leakage magnetic flux is diffracted through the slit 32. A magnetic field H can be formed on the upper surface of the bottom surface 7a, which is the installation surface of the installation groove 7, and an AC magnetic field, which is a power transmission medium and an information communication medium, is mutually exchanged between the RFID tag 1a and an external reader / writer terminal. The effect of transmitting and receiving data can be further improved.
[0133]
Note that a magnetic flux leakage path such as a slit may also be formed on the plate body 11 made of a conductive material serving as a protection body of the RFID tag 1a, the divided body itself such as the container body 21, the lid body 23, or the cap body 31a. good.
[0134]
In FIG. 15 and FIG. 16, reference numeral 41 denotes a notebook personal computer whose exterior is covered with a metal case serving as a conductive member. The notebook personal computer 41 is composed of a main body side 41a made of a conductive material provided with a keyboard 41a1 and a lid side 41b made of a conductive material provided with a liquid crystal display 41b1 as a split container. It is a means and is connected via a hinge member 41c serving as a rotation shaft so that it can be opened and closed.
[0135]
As shown in FIG. 16 (b), the notebook computer 41 has the main body side 41a and the lid side 41b closed with the surfaces 41a2 and 41b2 facing each other, and the lid side 41b opened to the main body side 41a. Although it is an example of the goods which can be performed, it is applicable also to the product management of various articles | goods, such as a portable information terminal (mobile personal computer) and a mobile telephone of the other similar structure.
[0136]
An RFID tag 1a is disposed between the surface 41b2 on the lid side 41b of the notebook computer 41 and the surface 41a2 on the main body side 41a. The memory 4b of the RFID tag 1a stores, for example, history data and lot management data of the notebook personal computer 41 provided with the RFID tag 1a. The RFID tag 1a stores unique code information of the notebook personal computer 41. The unique code information is read by a read / write terminal or the like, and history data, lot management data, or the like is browsed from another database. Is also possible.
[0137]
In the present embodiment, the RFID tag 1a is fixed to the surface 41b2 on the lid side 41b with an adhesive or adhesive material made of a non-conductive material, and the RFID tag is placed on a portion corresponding to the RFID tag 1a on the surface 41a2 on the main body side 41a. A recess 41a3 corresponding to the size of 1a is formed.
[0138]
Then, as shown in FIG. 16 (a), it is formed by leakage magnetic flux generated from the magnetic flux leakage path 12 which is a minute gap formed between the surface 41a2 of the main body side 41a and the surface 41b2 of the lid side 41b. Information stored in the RFID tag 1a using the magnetic field H can be extracted by a read / write terminal (not shown).
[0139]
Since the magnetic flux leakage path 12 which is a minute gap formed by the surface 41a2 on the main body side 41a and the surface 41b2 on the lid side 41b is formed in a state opened in the axial direction of the antenna coil 2a of the RFID tag 1a, Therefore, a magnetic flux penetrating the antenna coil 2a is easily formed, which contributes to the formation of the magnetic field H.
[0140]
The magnetic field H can be propagated from the magnetic flux leakage path 12 which is a minute gap formed by the surface 41a2 of the main body side 41a and the surface 41b2 of the lid side 41b, and the leakage magnetic flux generated from the magnetic flux leakage path 12 Information stored in the RFID tag 1a can be extracted by transmitting and receiving an AC magnetic field, which is a power transmission medium and an information communication medium, between the RFID tag 1a and an external read / write terminal (not shown). .
[0141]
Therefore, in various articles having the same form as these which can be opened by opening one side, such as a notebook computer, a portable information terminal (mobile personal computer), a mobile phone, etc., whose exterior is made of a metal case, Product management can be performed by arranging the RFID tag 1a between and extracting information stored in the RFID tag 1a.
[0142]
Therefore, even when re-inspecting a packaged product, information stored in the RFID tag a can be taken out from the outside of the packaging material, and workability is good because there is no need to unpack the packaging material once packaged. .
[0143]
FIG. 17A is a side explanatory view showing an example in which the RFID tag communication method is applied to a plurality of stacked steel plates as a reference example, and FIG. 17B is a perspective explanatory view of FIG. .
[0144]
17 (a) and 17 (b), a plurality of plate-shaped steel plates 51 serving as a plurality of plate-like conductive members are stacked via a batten 52, and an RFID is placed on the surface of each steel plate 51. A tag 1a is installed, a magnetic flux leakage path 12 is formed between the steel plate 51 and the steel plate 51, and between the RFID tag 1a and the outside of the steel plate 51 stacked using the leakage magnetic flux passing through the magnetic flux leakage path 12 It is configured to communicate with.
[0145]
The RFID tag 1a may be fixed to the steel plate 51 with an adhesive or adhesive material made of a non-conductive material, or a magnet holding the RFID tag 1a may be adsorbed to the steel plate 51.
[0146]
As shown in FIG. 17 (b), the RFID tag 1a is preferably arranged and fixed at the corner of the loaded steel plate 51 with its axial direction inclined obliquely (for example, 45 degrees), Since the magnetic flux leakage path 12 formed by a gap formed between the steel plate 51 and the steel plate 51 is formed in a state opened in the axial direction of the antenna coil 2a of the RFID tag 1a, a magnetic flux penetrating the antenna coil 2a is thereby formed. This contributes to the formation of the magnetic field H.
[0147]
The magnetic field H can propagate from the magnetic flux leakage path 12 formed by the gap formed by the steel plate 51 and the steel plate 51, and the RFID tag 1a and an external lead (not shown) are generated by the leakage magnetic flux generated from the magnetic flux leakage path 12. Information stored in the RFID tag 1a can be extracted by transmitting and receiving an AC magnetic field, which is a power transmission medium and an information communication medium, to and from a light terminal.
[0148]
In addition to the flat steel plate 51, it can be similarly applied to a gently curved curved plate or corrugated plate, and a plurality of stacked plate-like conductive members can be used instead of the steel plate 51, for example, , Printed circuit boards with electrical circuits formed of copper foil, various other plate-shaped metal articles made of various metal materials such as aluminum, copper, stainless steel, iron powder on resin, cement, concrete, etc. It can be applied to the case where a plurality of plate-like articles made of a magnetic material such as magnets, a material in which a magnetic material such as powder is folded or adhered to a cloth, or a magnetic material such as a magnet are stacked. In a state where a plurality of plate-like articles such as those are stacked, the RFID tag 1a is arranged between the articles, and information stored in the RFID tag 1a is taken out, so that product management, inventory management, etc. can be performed easily and efficiently. Can be done.
[0149]
Next, a communication method of the RFID tag 1b having the concentric disk-shaped antenna coil 2b will be described with reference to FIGS. In addition, about the structure similar to the RFID tag 1a which has the said cylindrical antenna coil 2a, the same code | symbol is attached | subjected and description is abbreviate | omitted.
[0150]
FIG. 18 is an exploded view showing a state in which an RFID tag having a concentric disk-shaped antenna coil arranged in the installation groove portion of the conductive member is covered with a plate-shaped protector having a convex portion inserted into the installation groove portion. FIG. 19 is an explanatory view, and FIG. 19 is a cross-sectional explanatory view showing a state where the plate-like protection body of FIG. 18 is fixed to the conductive member by the fixing means.
[0151]
20 is a front and side explanatory view showing the configuration of an RFID tag having a concentric disk-shaped antenna coil, and FIG. 21 is a schematic diagram showing a state of a magnetic field generated in the RFID tag having a concentric disk-shaped antenna coil. .
[0152]
FIG. 22 is a cross-sectional explanatory view showing a state where the RFID tag arranged in the installation groove portion of the conductive member is covered with a flat plate-shaped protective body, and FIG. 23 is a case where various slits are formed in the plate-shaped protective body. It is decomposition | disassembly explanatory drawing which shows an example.
[0153]
The RFID tag 1b shown in FIGS. 18 to 23 is also formed integrally with a concentric disk-shaped antenna coil 2b and a semiconductor IC chip 4 as a control unit directly connected without using a printed circuit board or the like. Thus, the RFID tag 1b can be downsized. The configuration of the control system of the RFID tag 1b is the same as that described above with reference to FIG.
[0154]
In the RFID tag 1b shown in FIG. 20, an antenna coil 2b, a semiconductor IC chip 4 and the like formed by winding in a concentric disk shape with multiple layers in the radial direction by a single wire are integrally sealed with a resin 61. It is stopped and the whole is configured in a disk shape.
[0155]
The RFID tag 1b has an outer diameter D in the radial direction of the antenna coil 2b. ₄ Outer diameter D according to ₃ It is sealed with a resin 61 having
[0156]
The outer diameter D of the resin 61 of the RFID tag 1b employed in this reference example is as follows. ₃ , And the outer diameter D of the antenna coil 2b ₄ And the inner diameter D of the antenna coil 2b ₅ An example is shown.
[0157]
[Table 2]

[0158]
Further, the thickness T of the resin 61 of the RFID tag 1b is about 0.7 mm to 12.0 mm, and the weight of the RFID tag 1b is about 0.7 g to 5.2 g.
[0159]
As an example of the antenna coil 2b, a copper wire having a diameter of about 30 μm is wound in a concentric disk shape with multiple layers in the radial direction by single wire winding, and the inductance of the antenna coil 2b is about 9.5 mH (frequency 125 kHz). The capacitance of the capacitor separately connected to the antenna coil 2b for resonance was about 170 pF (frequency 125 kHz).
[0160]
FIG. 21 shows a state of the magnetic field H generated from the RFID tag 1b in a free state.
[0161]
On the other hand, the conductive member 5 is provided with an installation groove portion 7 having a circular cross section corresponding to the size of the RFID tag 1b. The RFID tag 1b has a bottom surface whose antenna coil surface serves as the installation surface of the conductive member 5. A magnetic flux leakage path 12 is formed between the conductive member 5 and a plate 11 serving as a protector made of a conductive material such as a metal.
[0162]
A plate body 11 serving as a protection body shown in FIG. 18 and FIG. 19 has a cylindrical fitting portion 11a having a shape corresponding to the shape of the installation groove portion 7 at the center portion protruding toward the installation groove portion 7, and the fitting portion. A screw 10 serving as a fixing means is fixed to the tap hole 5b provided in the conductive member 5 through the through hole 11c formed in the flange 11b of the plate body 11 by positioning the 11a in the installation groove 7. The plate body 11 is fixed to the conductive member 5 by screwing. The conductive member 5 may be fixed using a tapping screw as the screw 10 without providing the tap hole 5b.
[0163]
The RFID tag 1b may be sealed in a glass container instead of the resin 61. Alternatively, the RFID tag 1b may be sealed with a flexible synthetic resin or the like so that the main body of the RFID tag 1b also serves as a buffer member.
[0164]
FIG. 19 also illustrates the state of the magnetic field H generated from the RFID tag 1b embedded in the installation groove 7 of the conductive member 5.
[0165]
22 (a) and 22 (b), the plate 11 serving as a protective body is a flat plate, and in FIG. 22 (a), the plate 11 is brought into direct contact with the conductive member 5 and fixed. An example of fixing with screws 10 as means is shown.
[0166]
Further, in FIG. 22B, a step portion 5c is formed on the upper surface side of the installation groove portion 7 of the conductive member 5, and a plate body 11 made of a flat plate is fitted to the step portion 5c. The surface of 11 and the surface of the conductive member 5 are substantially flush with each other to eliminate protrusions.
[0167]
FIG. 23 (a) shows a radial pattern from a portion corresponding to the center of the antenna coil 2b in a direction coinciding with the radial direction of the RFID tag 1b having the antenna coil 2b formed concentrically through the disk-shaped plate body 11. The outer diameter D of the antenna coil 2b ₄ A slit 11e having a length corresponding to is provided as a magnetic flux leakage path. The slit 11e can be closed with an adhesive or a filler.
[0168]
FIG. 23B shows a case where only one slit 11e is provided as a magnetic flux leakage path in the radial direction of the antenna coil 2b. The slit 11e can be closed with an adhesive or a filler.
[0169]
Leakage magnetic flux generated from the RFID tag 1b having the concentric disc-shaped antenna coil 2b passes through the magnetic flux H through the magnetic flux leakage path 12 and the slit 11e serving as the magnetic flux leakage path to the upper portion of the bottom surface 7a serving as the installation surface of the conductive member 5 by the diffraction phenomenon. And an AC magnetic field, which is an electric power transmission medium and an information communication medium, can be transmitted to and received from an external read / write terminal or the like.
[0170]
The plate body 11 and the cap body 31a are not only fixed to the conductive member 5 by screwing bonding or adhesive bonding, but are also fitted, crimped, screw-fitted, seam-bonded, adhesive-bonded. Thus, the magnetic flux leakage path may be fixed so that an amount of magnetic flux that can be transmitted and received at a practical level can be leaked. Seam bonding is a bonding between metal plates with high-density polyethylene or the like wound together at a bonding site.
[0171]
【The invention's effect】
Since the present invention has the above-described configuration and operation, even when the periphery of the RFID tag is covered with a conductive member, the RFID is utilized by utilizing the leakage magnetic flux passing through the magnetic flux leakage path formed in the conductive member. Communication can be performed between the tag and the outside of the conductive member.
[0172]
Further, the RFID tag is installed on an installation member made of a conductive material, and the surface side of the RFID tag is covered with a protection body made of a conductive material, so that the periphery of the RFID tag is surrounded by the installation member and the protection body Even in the state covered with the conductive member made of, communication can be performed using leakage magnetic flux passing through the magnetic flux leakage path formed between the installation member and the protection body or at least one of the protection body.
[0173]
In addition, even when the RFID tag is housed in a container made of a conductive material and the periphery of the RFID tag is covered with a conductive member made of the container, the leakage magnetic flux passing through the magnetic flux leakage path provided in the container is reduced. You can communicate using it.
[0174]
Further, an RFID tag having a cylindrical antenna coil and formed in a rod shape can be extremely miniaturized, so that it can be easily installed even when the installation area allowed for the conductive member is small.
[Brief description of the drawings]
FIG. 1 is an exploded explanatory view showing a state where a part of an RFID tag arranged in an installation groove portion of a conductive member is covered with a plate-like protector having a convex portion inserted into the installation groove portion.
2 is an explanatory cross-sectional view showing a state in which the plate-shaped protective body of FIG. 1 is fixed to a conductive member by various fixing means.
FIG. 3 is a front explanatory view showing a configuration of an RFID tag having a cylindrical antenna coil.
FIG. 4 is a block diagram showing a configuration of a control system of the RFID tag.
FIG. 5 is a schematic diagram showing a state of a magnetic field generated in an RFID tag having a cylindrical antenna coil.
6A is a cross-sectional explanatory view showing a state in which an RFID tag arranged in an installation groove portion of a conductive member is covered with a flat plate-shaped protector, and FIG. 6B is an arrangement groove portion of the conductive member. It is sectional explanatory drawing which shows a mode that the RFID tag covered with the plate-shaped protective body which formed the accommodating part which accommodates a part of RFID tag was formed.
FIG. 7 is an exploded explanatory view showing an example in which a linear slit is formed in a plate-shaped protective body.
FIG. 8 is a cross-sectional explanatory view showing a state in which an RFID tag housed in a container body having an opening is covered with a lid that covers the opening.
FIG. 9 is an explanatory cross-sectional view showing a state in which an RFID tag arranged in an installation groove portion of a conductive member is covered with a protective body made of a cap body in which a storage portion for storing the RFID tag is formed.
FIG. 10 is an exploded explanatory view showing an example when the installation groove and the cap body are configured to have a circular cross section.
11A and 11B are a cross-sectional explanatory view and an exploded explanatory view showing a state in which a protective body made of a cap body is mounted in an installation groove portion of a conductive member by screwing as an example of a fixing means.
FIGS. 12A and 12B are a cross-sectional explanatory view and an exploded explanatory view showing a state where a protective body made of a cap body is mounted in an installation groove portion of a conductive member by screwing as an example of a fixing means.
FIG. 13 is an explanatory cross-sectional view showing a state in which a cutout is provided in the axial direction of a cylindrical antenna coil of a protective body made of a cap body.
FIG. 14 is an exploded explanatory view showing a state where a cutout is provided in the axial direction of a cylindrical antenna coil of a protective body made of a cap body having a circular cross section.
FIG. 15 is an explanatory perspective view illustrating an example in which the RFID tag communication method according to the present invention is applied to a notebook personal computer.
16A is an explanatory plan view showing an example in which the RFID tag communication method according to the present invention is applied to a notebook personal computer, and FIG. 16B is a plan view illustrating the RFID tag communication method according to the present invention. It is side explanatory drawing which shows an example at the time of applying to.
FIG. 17A is a side view illustrating an example in which an RFID tag communication method is applied to a plurality of stacked steel plates as a reference example, and FIG. 17B is an RFID tag communication method using a steel plate as a reference example. It is perspective explanatory drawing which shows an example at the time of applying to what was piled up two or more.
FIG. 18 shows a state in which an RFID tag having a concentric disk-shaped antenna coil disposed in an installation groove portion of a conductive member is covered with a plate-shaped protector having a convex portion inserted into the installation groove portion. FIG.
19 is a cross-sectional explanatory view showing a state where the plate-shaped protective body of FIG. 18 is fixed to a conductive member by a fixing means.
FIG. 20 is a front and side explanatory view showing a configuration of an RFID tag having a concentric disk-shaped antenna coil.
FIG. 21 is a schematic diagram illustrating a state of a magnetic field generated in an RFID tag having a concentric disk-shaped antenna coil.
22 is an explanatory cross-sectional view showing a state in which an RFID tag arranged in an installation groove portion of a conductive member is covered with a flat plate-shaped protector. FIG.
FIG. 23 is an exploded explanatory view showing an example when various slits are formed in a plate-shaped protective body.
[Explanation of symbols]
1a, 1b ... RFID tag
2a, 2b ... Antenna coil
3. Core member
4 ... Semiconductor IC chip
4a ... CPU
4b ... Memory
4c ... transceiver
4d: Capacitor
5 ... Conductive member
5a ... Surface
5b ... Tap hole
5c ... Step
6 ... Glass container
7 ... Installation groove
7a ... Bottom
7b ... Side
7b1 ... Screw part
8 ... resin
10 ... Screw
11 ... Plate
11a ... Fitting part
11b ... Buttocks
11c ... through hole
11d ... box
11e ... Slit
12 ... Magnetic flux leakage path
13 ... Spacer
14… Adhesive
15 ... Storage section
21 ... Container body
21a ... Tap hole
22 ... Opening
22a ... side
22b ... Bottom
23… lid
23a ... Fitting part
23b ... Buttocks
23c ... Through hole
31a ... Cap body
31a1 ... Side plate
31a2 ... top plate
31a3… Inner wall surface
31a4… Outer wall surface
31a5… Threaded part
31a6… engagement hole
32 ... Slit
41… Notebook PC
41a ... Body side
41a1 ... Keyboard
41a2 ... surface
41a3… Recess
41b ... Lid side
41b1 ... Liquid crystal display
41b2 ... surface
41c ... Hinge member
51 ... Steel
52 ... Batten
61… Resin

Claims (6)

A method of communicating in a state where the periphery of an RFID tag having a cylindrical antenna coil and a control unit and entirely formed in a rod shape is covered with a conductive member,
Formed in the conductive member is a magnetic flux leakage path consisting of a gap that allows leakage of magnetic flux for communication between the RFID tag and the outside of the conductive member, and the magnetic flux leakage path is inside the conductive member. The RFID tag extends from the vicinity of the tip of the RFID tag to the outside of the conductive member, and communication is performed between the RFID tag and the outside of the conductive member using leakage magnetic flux passing through the magnetic flux leakage path. RFID tag communication method.   An installation groove portion is provided in an installation member made of a conductive material, and the RFID tag is installed in the installation groove portion. At this time, the RFID tag is disposed in parallel with the bottom surface of the installation groove portion, and the surface of the RFID tag By covering the side of the RFID tag with a conductive member comprising the installation member and the protective body by covering the side with a protective body made of a conductive material, between the installation member and the protective body 2. The RFID tag communication method according to claim 1, wherein communication is performed between the RFID tag and the outside of the protector by using a leakage magnetic flux passing through a magnetic flux leakage path formed on the outer surface of the RFID tag.   By storing the RFID tag in a container made of a conductive material, the periphery of the RFID tag is covered with a conductive member made of the container, and leakage magnetic flux passing through a magnetic flux leakage path provided in the container is reduced. The RFID tag communication method according to claim 1, wherein communication is performed using the RFID tag according to claim 1.   4. The RFID tag communication method according to claim 3, wherein the container is constituted by a plurality of division bodies that can be divided, and a magnetic flux leakage path is formed on the division surface.   The RFID tag communication method according to claim 4, wherein the container is constituted by a container body having an opening and a lid that covers the opening.   The RFID tag communication method according to claim 4, wherein the divided bodies are connected to each other by an opening / closing means so as to be opened and closed.

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