JP4333071B2

JP4333071B2 - Biological information measuring device

Info

Publication number: JP4333071B2
Application number: JP2002023033A
Authority: JP
Inventors: 融士山本; 和俊永井; 伸夫元治; 洋永里; 真平野
Original assignee: Panasonic Corp; Matsushita Electric Works Ltd
Current assignee: Panasonic Corp; Panasonic Electric Works Co Ltd
Priority date: 2002-01-31
Filing date: 2002-01-31
Publication date: 2009-09-16
Anticipated expiration: 2022-01-31
Also published as: JP2003220047A

Description

【０００１】
【発明の属する技術分野】
本発明は、人体のインピーダンスと人体の個人別情報により体脂肪率等の生体情報を算出する生体情報測定装置に関するものである。
【０００２】
【従来の技術】
近年、個人で健康管理を行う指標の一つとして人体インピーダンスを測定することによる体脂肪率などの生体情報測定装置が急激に普及してきている。この生体情報測定装置は図１０に示すように本体１にリード線２で接続された高周波電流を人体へ印加する第１の電極対３、高周波電流の身体通電経路内に配置して人体抵抗電位を測定する第２の電極対４とからなり、第２の電極対４の内の一つの電極の人体抵抗電位と他方の電極の人体抵抗電位から第２の電極対間（すなわち人体抵抗の測定部位間）の電位差と、人体に印加している高周波電流値とによって人体のインピーダンスを測定するものである。この人体インピーダンス値と、予め統計的手法によって導き出した相関式をもとに、体脂肪率などの生体情報を算出している。
【０００３】
また、この種の生体情報測定装置として、人体に流れる高周波電流の電流経路を両手間としたものや、両足間としたもの、また、人体の胴体部を含めた電流経路としたものなどがある。更に、日々の測定をより容易に人体インピーダンスを測定して体脂肪率などの生体情報を測定するものとして、特開２０００−３３３９２７公報に記載されている体脂肪率計がある。これは、図１１に示すように様式便座５とこの便座にそれぞれ配設した右尻部と左尻部が接触する尻電極対６と、左右いづれか一方の手に接触する手電極対７があり、これらの電極間の人体インピーダンスを測定して体脂肪率を算出して報知手段８へ体脂肪率を転送し、使用者に対して測定された体脂肪率を報知するものである。
【０００４】
【発明が解決しようとする課題】
しかしながら、前記従来の体脂肪率計では様式便座に座り、右尻部や左尻部に尻電極部を接触させる際に、電極との接触面である人体の尻部の肌が乾燥していたり、様式便座の前方へ浅く座ったり上半身を前方へ傾けたりして、尻電極部に人体の体重を十分加重できていないときには、人体と電極面との接触抵抗が大きくなってしまう。接触抵抗が大きくなると、高周波電流を十分に流すことができなくなり人体インピーダンスを測定できなくなるばかりでなく、人体が高周波電流を印加する電極対から電気的に大きな接触抵抗で接続された場合、人体自身がＡＣ電源部を有した他の機器などからの電源ハムノイズを受け易くなることで、人体抵抗電位が安定しなくなり、正確な人体インピーダンスを測定できないという課題を有している。また、接触抵抗を小さくするために電極装着する部位に心電計による心電図測定の際の電極装着と同様に導電性クリームを塗布しなければならないという課題を有している。
【０００５】
本発明は、前記従来の課題を解決するもので、人体に高周波電流を印加する定電流印加手段の基準電位側の電極を人体との接触抵抗が小さくなる部位に配置することにより、人体と電極間の接触抵抗の影響を低減させ、正確な人体インピーダンスを測定することができる生体情報測定装置を提供するものである。
【０００６】
【課題を解決するための手段】
前記従来の課題を解決するために、本発明の生体情報測定装置は、人体に高周波電流を印加する定電流印加手段の基準電位側の電極を人体と電極間の接触抵抗が小さくなる部位に配置するものである。
【０００７】
上記発明によれば、人体自身がＡＣ電源部を有した他の機器などからの電源ハムノイズを受けにくくなり、人体抵抗電位が安定して、正確な人体インピーダンスを測定することができる。
【０００８】
【発明の実施の形態】
請求項１に記載の発明は、基準電位から人体抵抗に応じて印加電圧を変えて一定の電流を人体の測定部位間に印加する定電流印加手段と、人体の測定部位間に前記定電流印加手段により高周波電流を印加する第１の電極対と、この高周波電流の身体通電経路内に配置して人体抵抗電位を測定する第２の電極対と、前記第１の電極対間に流れる高周波電流と前記第２の電極対間の人体抵抗電位により人体インピーダンスを計測する計測手段と、人体の個人別情報を入力する人体個別情報手段と、前記人体インピーダンスと前記人体の個人別情報により体脂肪率等の生体情報を算出する制御手段とを備え、前記第１の電極対の内、定電流印加手段の基準電位側の電極は、人体との接触抵抗が低くなる部位に配置するもので、第１の電極対は、人体の一方の手の指で挟み込まれる指電極部と、人体の他方の手で握られる手電極部とにそれぞれ配設され、定電流印加手段の基準電位側の電極を手電極部に配設したことで、手の指より比較的汗腺が多く、電極との接触抵抗が小さくなるため、人体自身がＡＣ電源部を有した他の機器などからの電源ハムノイズを受けにくくなり、人体抵抗電位が安定して、正確な人体インピーダンスを測定することができる。
【０００９】
【実施例】
以下、本発明の実施例及び参考例について図面を用いて説明する。
【００１０】
（参考例１）
図１は、本発明の第１の参考例における生体情報測定装置の構成図である。図において、定電流印加手段９は基準電位から人体抵抗に応じて印加電圧を変えて一定の電流を人体の測定部位間に印加するものである。１０は電極１０ａ、１０ｂからなる第１の電極対で人体の手や足などの測定部位間に配置され、定電流印加手段９によって人体に一定の電流が印加される。１１は電極１１ａ、１１ｂからなる第２の電極対で、人体に印加された電流が流れる経路内に配置されており、計測手段１２により第２の電極対１１間の電位差から人体インピーダンスを計測する。また、人体の性別、年齢、身長、体重などの各個人毎の情報を入力する人体個別情報手段１３の個人別情報と、計測手段１２にて計測された人体インピーダンスによって、体脂肪率等の生体情報を算出する制御手段１４を有している。
【００１１】
図２（ａ）は第１の電極対１０の内の電極１０ａと第２の電極対１１の内の電極１１ａの人体への接触の位置関係を示したもので、矢印で示すように電極１０ａは手のひらの人差し指側に配置され、電極１１ａは手のひらの小指側に配置されており、使用者が手電極部１５を手で握ることにより人体（手）と電極１０ａ、１１ａとが接触するように構成されている。また、図２（ｂ）は第１の電極対１０の内の電極１０ｂと第２の電極対１１の内の電極１１ｂの人体への接触の位置関係を示したもので、矢印で示すように電極１０ｂは足の裏の指側に配置され、電極１１ｂは足の裏の足首側に配置されており、使用者が足電極部１６の上に乗ることにより人体と電極とが接触するように構成されている。
【００１２】
定電流印加手段９の内部回路は図３に示すように、周波数ｆの高周波信号を発生する高周波信号発生部１７と人体インピーダンスに応じて人体への印加電圧を変えて一定電流を印加する定電流発生部１８から構成されており、定電流発生部１８の出力端子は出力インピーダンスが低く、定電流印加手段９の基準電位としている。印加周波数は人体内部の細胞膜を印加電流が通過できるように１０〜１００ｋＨｚ程度としており、印加電流は使用者が感じないように０．１〜１ｍＡ程度としている。
【００１３】
計測手段１２の内部回路は図４に示すように、差動増幅部１９、フィルター部２０、演算部２１から構成されている。ここで、第２の電極対１１のそれぞれの電極の人体抵抗電位が差動増幅部１９に入力され第２の電極対１１の人体抵抗電位差信号が出力される。電極１１ａ、１１ｂのそれぞれの人体抵抗電位信号は、図５（ａ）に示すように、定電流印加手段９からの高周波電流の周波数ｆの信号に同期した信号となる。この信号の差（図中の斜線部）である人体抵抗電位差は、第２の電極対１１間の人体抵抗電位の差が大きい、すなわち、人体インピーダンスが大きいほど振幅が大きくなる。次に、この人体抵抗電位差信号の高周波信号発生部１７の印加周波数ｆ以外のノイズはフィルター部２０にてカットされ、さらに、演算部２１により、第１の電極対１０間に印加した一定の電流と人体抵抗電位差信号により人体インピーダンスが演算される。なお、第２の電極対１１に接続されている差動増幅部１９の入力端子は数１００ｋΩ程度と入力インピーダンスが高く、第２の電極対１１と人体との接触抵抗が１００〜１ｋΩ程度でもほとんど影響しない設定となっている。
【００１４】
次に、各構成要素についての動作を説明する。使用者は人体の性別、年齢、身長、体重などの各個人毎の情報を入力する人体個別情報手段１３へ個人別情報を入力して、手電極部１５を握り、足電極部１６の上に乗って、人体と電極とを接触させる。定電流印加手段９により一定の高周波電流を人体に印加し、計測手段１２にて人体インピーダンスを計測する。制御手段１４では、人体個別情報手段１３にて設定された個人別情報のうち身長と体重と、計測された人体インピーダンスから予め統計的手法によって求められた「人体インピーダンスと体密度の相関式」により、体脂肪率を算出して、報知手段（図示せず）にて使用者に体脂肪率を報知する。
【００１５】
体脂肪率の算出方法としては一般的にＢｒｏｚｅｋ（ブロゼク）の式が有名であり、人体インピーダンスと体密度の関係から、体脂肪率＝（（４．５７０／体密度）−４．４１２）×１００により求められる。更に、性別、年齢などによってより体密度との相関を高めるために計算式を分けて使用している。
【００１６】
ここで、人体と、第１の電極対１０および第２の電極対１１との接触抵抗と人体インピーダンス計測との関係を述べる。第２の電極対１１に接続されている差動増幅部１９の入力端子は数１００ｋΩ程度と入力インピーダンスが高く、第２の電極対１１と人体との１００〜１ｋΩ程度の接触抵抗はほとんど影響しないが、第１の電極対１０と人体との接触抵抗が大きい場合、人体自身がＡＣ電源部を有した他の機器などからの電源ハムノイズを受け易くなる。特に接触抵抗が大きい場合は、図５（ｂ）に示すように、第２の電極対１１からの計測手段１２への人体抵抗電位差信号は、定電流印加手段９での高周波電流の周波数ｆの信号に電源ハムノイズの５０Ｈｚや６０Ｈｚが重畳した信号となり、電源ハムノイズの重畳の程度によっては計測手段１２の電圧測定範囲を超過（点線で示す）してしまう。人体抵抗電位差信号が計測手段１２の電圧測定範囲を超過していない期間（Ｔ１）は、電源ハムノイズが重畳していてもフィルター部２０にて高周波信号発生部１７の印加周波数ｆ以外のノイズは電源ハムノイズを含めカットされるが、人体抵抗電位差信号が計測手段１２の電圧測定範囲を超過した期間（Ｔ２、Ｔ３）は、人体抵抗電位差信号の振幅が小さくなり、正確な人体抵抗電位差信号を検出できず、正確な人体インピーダンスを計測することができなくなってしまう。
【００１７】
一般的に、人体の生理学的発汗として、気温が高いときなどに出る汗など体温調節のための温熱性発汗と、驚いたときや感動したとき、緊張したときなどに出る汗など精神性発汗がある。全身の内、手のひらや足の裏などは温熱性発汗に加え精神性発汗が起こり、他の部分は温熱性発汗のみが起こる。このため、手のひらや足の裏は人体の他の表面に比べ汗が出やすく、人体表面と電極との接触抵抗としては小さくなる。
【００１８】
本参考例では、手のひらと足の裏にて人体インピーダンスを計測しており、計測の際には手のひらは手電極部１５を握り、足の裏は足電極部１６の上に乗ることとしている。手のひらと足の裏の各電極部との接触抵抗は、手電極部１５を握る握力に比べ、足電極部１６には人体の体重がかかるため、足の裏と足電極部１６との接触抵抗は小さくなる。よって、人体インピーダンスを計測する第１の電極対１０ａ、１０ｂの内の、定電流印加手段９の基準電位側に接続されている電極１０ｂを足の裏側に配置することで、人体自身がＡＣ電源部を有した他の機器などからの電源ハムノイズを受けにくくなり、人体抵抗電位が安定して、正確な人体インピーダンスを測定することができる。
【００１９】
（参考例２）
図６は、本発明の第２の参考例における生体情報測定装置の外観図である。図に示すように、本参考例の生体情報測定装置は、電極２５ａ、２５ｂからなる第１の電極対２５、及び電極２６ａ、２６ｂからなる第２の電極対２６が便座２２及び本体２３の側部に設けた手電極部２４にそれぞれ設けられている。
【００２０】
本参考例では、参考例１の定電流印加手段９の基準電位側に接続された第１の電極対１０ｂにあたる電極が、右手に接触する電極２５ｂとして手電極部２４の手のひらの人差し指側に配置されたものであり、それ以外の同じ構成および、同じ作用効果を果たす部分については参考例１と同様であり詳細な説明を省略する。
【００２１】
上記構成にて、手と大腿部にて人体インピーダンスを計測しており、計測の際には手で手電極部２４を握ることで、電極２５ｂ、２６ｂが手のひらに接触し、大腿部を露出した状態で便座２２に座ることにより、大腿部が便座２２に配置された電極２５ａ、２６ａに接触する。大腿部と電極２５ａ、２６ａとの接触抵抗は、便座２２への座り方や上半身の姿勢により電極への人体の体重のかかり方が変化して不安定なものになる。また、人体の汗腺は手のひらには蜜に分布しているが、大腿部の汗腺は手のひらに比べると少なく、大腿部と便座２２に設けた電極２５ａ、２６ａとの接触抵抗は手のひらよりも大きくなる。そこで、人体インピーダンスを計測する第１の電極対２５ａ、２５ｂの内、定電流印加手段の基準電位側に接続されている電極２５ｂを手のひら側に配置することで、人体自身がＡＣ電源部を有した他の機器などからの電源ハムノイズを受けにくくなり、人体抵抗電位が安定して、正確な人体インピーダンスを測定することができる。
【００２２】
（参考例３）
図７（ａ）は第３の参考例における生体情報測定装置の外観図である。図に示すように、本参考例の生体情報測定装置は腕電極部２７と手電極部２８とをリード線２９にて接続したものである。腕電極部２７にはマジックテープ（登録商標）等の巻きつけ固定部３０にて使用者の一方の腕に巻きつけて固定される。また、腕電極部２７の使用者の皮膚に接触する面には、第１の電極対３１の内の電極３１ａと、第２電極対３２の内の電極３２ａが配置されている。手電極部２８には第１の電極対３１の内の電極３１ｂと、第２電極対３２の内の電極３２ｂが配置されている。使用状態は図７（ｂ）に示すように一方の腕に腕電極部２７を巻きつけ、他方の手にて手電極部２８を握る。
【００２３】
本参考例では、参考例１の定電流印加手段９の基準電位側に接続された第１の電極対１０の電極１０ｂにあたる電極が手電極部２８の電極３１ｂとして手のひらの人差し指側に配置されたものであり、それ以外の同じ構成および、同じ作用効果を果たす部分については参考例１と同様であり詳細な説明を省略する。
【００２４】
上記構成により、手と腕にて人体インピーダンスを計測しており、計測の際には腕には腕電極部２７が巻きつけられ、手で手電極２８を握ることとしている。腕の腕電極部２７との接触抵抗は、マジックテープ等の巻きつけ固定部３０の巻きつけ方や腕の皮膚の乾燥度合いによって電極と腕の皮膚表面との接触抵抗が変化して不安定なものになる。また、人体の汗腺は手のひらには蜜に分布しているが、腕の表面の汗腺は手のひらに比べると少なく、腕と腕電極部２７との接触抵抗は手のひらよりも大きくなる。そこで、人体インピーダンスを計測する第１の電極対３１の内の、定電流印加手段９の基準電位側に接続されている第１の電極３１ｂを手のひら側に配置することで、人体自身がＡＣ電源部を有した他の機器などからの電源ハムノイズを受けにくくなり、人体抵抗電位が安定して、正確な人体インピーダンスを測定することができる。
【００２５】
（実施例１）
図８（ａ）は本発明における第１の実施例における生体情報測定装置の外観図である。図に示すように本実施例の生体情報測定装置は、一方の手の指が接触する指電極部３３と手電極部３４が一体に構成されている。また、指電極部３３の使用者の指が接触する面には、第１の電極対３５の内の電極３５ａと、第２電極対３６の内の電極３６ａが配置され、手電極部３４には第１の電極対３５の内の電極３５ｂと、第２電極対３６の内の電極３６ｂが配置されている。使用状態は図８（ｂ）に示すように一方の手の指で指電極部３３をはさみ込み、他方の手にて手電極部３４を握った状態となる。
【００２６】
本実施例では、参考例１の定電流印加手段９の基準電位側に接続された第１の電極対１０ｂにあたる電極が手電極部３４の電極３５ｂとして手のひらの人差し指側に配置されたものであり、それ以外の同じ構成および、同じ作用効果を果たす部分については参考例１と同様であり詳細な説明を省略する。
【００２７】
上記構成にて、一方の手の指と他方の手のひらにて人体インピーダンスを計測しており、計測の際には一方の手の指は指電極部３３をはさみ込み、他方の手のひらで手電極部３４を握ることとしている。一方の手の指と指電極部３３との接触抵抗は、一方の手の指の接触強度（指の挟みこむ力）や指の皮膚の乾燥度合いによって電極と手の指の皮膚表面との接触抵抗が変化して不安定なものになる。また、人体の汗腺は手のひらには蜜に分布しているが、指の表面の汗腺は手のひらに比べると少なく、また、電極との接触面積も手のひらよりも小さくなるため、手の指と指電極部３３との接触抵抗は手のひらよりも大きくなる。そこで、人体インピーダンスを計測する第１の電極対３５の内、定電流印加手段９の基準電位側に接続されている第１の電極３５ｂを手のひら側に配置することで、人体自身がＡＣ電源部を有した他の機器などからの電源ハムノイズを受けにくくなり、人体抵抗電位が安定して、正確な人体インピーダンスを測定することができる。
【００２８】
（参考例４）
図９（ａ）は本発明における第４の参考例における生体情報測定装置の外観図である。図に示すように、本発明の生体情報測定装置は一方の手の指が接触する指電極部３７と手首電極部３８が一体に構成されている。また、手首電極部３８にはマジックテープ等の巻きつけ固定部３９にて使用者の一方の手首に巻きつけて固定される。また、指電極部３７の使用者の指が接触する面には、第１の電極対４０の内の電極４０ａと、第２電極対４１の内の電極４１ａが配置されている。手首電極部３８には第１の電極対４０の内の電極４０ｂと、第２電極対４１の内の電極４１ｂが配置されている。使用状態は図９（ｂ）に示すように一方の手の指で指電極部３７をはさみ込み、他方の手首に手首電極部３８を巻きつけた状態となる。
【００２９】
本参考例では、参考例１の定電流印加手段９の基準電位側に接続された第１の電極対１０ｂにあたる電極が指電極部３７の電極４０ａとして手の指側に配置されたものであり、それ以外の同じ構成および、同じ作用効果を果たす部分については参考例１と同様であり詳細な説明を省略する。
【００３０】
上記構成により、一方の手の指と他方の手首にて人体インピーダンスを計測しており、計測の際には一方の手の指は指電極部３７をはさみ込み、他方の手首には手首電極部３８が巻きつけられることとしている。手首の手首電極部３８との接触抵抗は、マジックテープ等の巻きつけ固定部３９の巻きつけ方や手首の皮膚の乾燥度合いによって電極と手首の皮膚表面との接触抵抗が変化して不安定なものになる。また、人体の汗腺は手のひらには蜜に分布しており、指の表面の汗腺も同じく多く分布しているが、手首の皮膚の表面には汗腺分布が少なく、手首と手首電極部３８との接触抵抗は手の指よりも大きくなる。そこで、人体インピーダンスを計測する第１の電極対４０の内、定電流印加手段９の基準電位側に接続されている電極４０ａを手の指側に配置することで、人体自身がＡＣ電源部を有した他の機器などからの電源ハムノイズを受けにくくなり、人体抵抗電位が安定して、正確な人体インピーダンスを測定することができる。
【００３１】
【発明の効果】
以上のように、請求項１に記載の発明によれば、人体に高周波電流を印加する定電流手段の基準電位側に接続された第１の電極を人体と第１の電極対間の接触抵抗が低くなる部位に配置したことで、人体自身がＡＣ電源部を有した他の機器などからの電源ハムノイズを受けにくくなり、人体抵抗電位が安定して、正確な人体インピーダンスを測定することができる。
【図面の簡単な説明】
【図１】本発明の参考例１における生体情報測定装置の構成図
【図２】（ａ）本発明の参考例１における生体情報測定装置の電極と手の接続図
（ｂ）本発明の参考例１における生体情報測定装置の電極と足の接続図
【図３】本発明の参考例１における定電流印加手段の内部回路図
【図４】本発明の参考例１における計測手段の内部回路図
【図５】（ａ）人体抵抗電位信号の波形図
（ｂ）人体抵抗電位信号に電源ハムノイズが重畳したときの波形図
【図６】本発明の参考例２における生体情報計測装置の外観図
【図７】（ａ）本発明の参考例３における生体情報計測装置の外観図
（ｂ）本発明の参考例３における生体情報計測装置と人体との接続図
【図８】（ａ）本発明の実施例１における生体情報計測装置の外観図
（ｂ）本発明の実施例１における生体情報計測装置と人体との接続図
【図９】（ａ）本発明の参考例４における生体情報計測装置の外観図
（ｂ）本発明の参考例４における生体情報計測装置と人体との接続図
【図１０】従来の生体情報測定装置の構成図
【図１１】従来の体脂肪率計の外観図
【符号の説明】
９定電流印加手段
１０、２５、３１、３５、４０第１の電極対
１１、２６、３２、３６、４１第２の電極対
１２計測手段
１３人体個別情報手段
１４制御手段[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a biological information measuring apparatus that calculates biological information such as a body fat percentage based on the impedance of a human body and individual information of the human body.
[0002]
[Prior art]
2. Description of the Related Art In recent years, biological information measuring devices such as body fat percentage by measuring human body impedance as one of the indicators for personal health management have rapidly spread. As shown in FIG. 10, this biological information measuring device is arranged in a body energization path of a high frequency current, a first electrode pair 3 for applying a high frequency current connected to a main body 1 by a lead wire 2 to a human body, and a human body resistance potential. The second electrode pair 4 is used to measure the human body resistance potential of one electrode of the second electrode pair 4 and the human body resistance potential of the other electrode. The impedance of the human body is measured by the potential difference between the parts) and the high-frequency current value applied to the human body. Based on the human body impedance value and a correlation equation derived in advance by a statistical method, biological information such as a body fat percentage is calculated.
[0003]
Further, as this type of biological information measuring device, there are a device that uses a current path of a high-frequency current flowing through the human body between both hands, a device that uses both feet, and a device that uses a current path including the torso of the human body. . Furthermore, there is a body fat percentage meter described in Japanese Patent Application Laid-Open No. 2000-333927 as a means for measuring body impedance more easily by measuring human body impedance and measuring biological information such as body fat percentage. As shown in FIG. 11, there are a style toilet seat 5, a buttocks electrode pair 6 in which the right buttocks and the left buttocks are respectively disposed on the toilet seat, and a hand electrode pair 7 in contact with either the left or right hand. The body fat rate is calculated by measuring the human body impedance between these electrodes, and the body fat rate is transferred to the notifying means 8 to notify the user of the measured body fat rate.
[0004]
[Problems to be solved by the invention]
However, in the conventional body fat percentage meter, when sitting on the style toilet seat and contacting the buttocks electrode part to the right buttocks or left buttocks, the skin of the buttocks of the human body that is the contact surface with the electrodes may be dry If the body weight is not sufficiently applied to the butt electrode portion by sitting shallowly in front of the style toilet seat or tilting the upper body forward, the contact resistance between the human body and the electrode surface is increased. When the contact resistance increases, not only the high-frequency current cannot flow sufficiently and the human body impedance cannot be measured, but also when the human body is electrically connected from the electrode pair to which the high-frequency current is applied with a large contact resistance, the human body itself However, since the human body resistance potential becomes unstable due to the susceptibility to power supply hum noise from other devices having an AC power supply unit, accurate human body impedance cannot be measured. Moreover, in order to reduce contact resistance, it has the subject that the electroconductive cream must be apply | coated like the electrode mounting | wearing at the time of the electrocardiogram measurement by an electrocardiograph in the site | part which mounts an electrode.
[0005]
The present invention solves the above-mentioned conventional problems, and by arranging an electrode on the reference potential side of constant current applying means for applying a high-frequency current to the human body at a site where contact resistance with the human body is reduced, the human body and the electrode It is intended to provide a biological information measuring apparatus that can reduce the influence of contact resistance between the two and measure accurate human body impedance.
[0006]
[Means for Solving the Problems]
In order to solve the above-mentioned conventional problems, the biological information measuring device of the present invention is arranged such that the electrode on the reference potential side of the constant current applying means for applying a high-frequency current to the human body is located at a portion where the contact resistance between the human body and the electrode is reduced To do.
[0007]
According to the above invention, the human body itself is less susceptible to power supply hum noise from other devices having an AC power supply unit, the human body resistance potential is stabilized, and accurate human body impedance can be measured.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
According to the first aspect of the present invention, there is provided a constant current applying means for applying a constant current between the measurement parts of the human body by changing the applied voltage from the reference potential according to the human body resistance, and applying the constant current between the measurement parts of the human body. A first electrode pair for applying a high-frequency current by means; a second electrode pair for measuring a human body resistance potential placed in a body energization path of the high-frequency current; and a high-frequency current flowing between the first electrode pair Measuring means for measuring human body impedance by means of a human body resistance potential between the second electrode pair, human body individual information means for inputting individual personal information of the human body, and body fat percentage by the human body impedance and personal information of the human body Control means for calculating biological information such as, and the electrode on the reference potential side of the constant current applying means in the first electrode pair is arranged at a part where the contact resistance with the human body is low. 1 pair of electrodes, the body The finger electrode portion is sandwiched by one of the fingers, are respectively arranged on the hand electrode portion to be held in the body of the other hand, it is disposed in the hand electrode portion reference potential side electrode of constant current applying means Since there are relatively more sweat glands than the fingers of the hand and the contact resistance with the electrode is small, the human body itself is less susceptible to power supply hum noise from other devices having an AC power supply, and the human body resistance potential is stabilized. Thus, accurate human body impedance can be measured.
[0009]
【Example】
Hereinafter, examples and reference examples of the present invention will be described with reference to the drawings.
[0010]
(Reference Example 1)
FIG. 1 is a configuration diagram of a biological information measuring apparatus according to a first reference example of the present invention. In the figure, the constant current applying means 9 applies a constant current between the measurement parts of the human body by changing the applied voltage according to the human body resistance from the reference potential. Reference numeral 10 denotes a first electrode pair composed of electrodes 10a and 10b, which is arranged between measurement parts such as a human hand and a foot. A constant current applying means 9 applies a constant current to the human body. Reference numeral 11 denotes a second electrode pair composed of electrodes 11a and 11b, which is arranged in a path through which a current applied to the human body flows. The human body impedance is measured from the potential difference between the second electrode pair 11 by the measuring means 12. . Also, the body fat percentage and the like of the body fat are determined by the individual information of the human body individual information means 13 for inputting information for each individual such as the sex, age, height and weight of the human body and the human body impedance measured by the measuring means 12. Control means 14 for calculating information is included.
[0011]
FIG. 2A shows the positional relationship of contact of the electrode 10a in the first electrode pair 10 and the electrode 11a in the second electrode pair 11 with the human body, and the electrode 10a as indicated by an arrow. Is arranged on the index finger side of the palm, and the electrode 11a is arranged on the little finger side of the palm so that the human body (hand) and the electrodes 10a, 11a come into contact with each other when the user holds the hand electrode portion 15 with his / her hand. It is configured. FIG. 2B shows the positional relationship between the electrode 10b in the first electrode pair 10 and the electrode 11b in the second electrode pair 11 in contact with the human body, as indicated by arrows. The electrode 10b is arranged on the finger side of the sole of the foot, and the electrode 11b is arranged on the ankle side of the sole of the foot so that the human body and the electrode come into contact with each other when the user rides on the foot electrode portion 16. It is configured.
[0012]
As shown in FIG. 3, the internal circuit of the constant current applying means 9 includes a high frequency signal generator 17 that generates a high frequency signal of frequency f and a constant current that changes a voltage applied to the human body according to the human body impedance and applies a constant current. The output terminal of the constant current generator 18 has a low output impedance and is used as a reference potential for the constant current application means 9. The applied frequency is about 10 to 100 kHz so that the applied current can pass through the cell membrane inside the human body, and the applied current is about 0.1 to 1 mA so that the user does not feel it.
[0013]
As shown in FIG. 4, the internal circuit of the measuring means 12 includes a differential amplifier 19, a filter 20, and a calculator 21. Here, the human body resistance potential of each electrode of the second electrode pair 11 is input to the differential amplifier 19 and the human body resistance potential difference signal of the second electrode pair 11 is output. As shown in FIG. 5A, the human body resistance potential signals of the electrodes 11a and 11b are signals synchronized with the signal of the frequency f of the high-frequency current from the constant current applying means 9. The difference in the human body resistance potential, which is the difference between the signals (shaded portion in the figure), has a larger amplitude as the difference in the human body resistance potential between the second electrode pair 11 is larger. Next, noise other than the applied frequency f of the high-frequency signal generation unit 17 of the human body resistance potential difference signal is cut by the filter unit 20, and a constant current applied between the first electrode pair 10 by the calculation unit 21. The human body impedance is calculated from the human body resistance potential difference signal. Note that the input terminal of the differential amplifier 19 connected to the second electrode pair 11 has a high input impedance of about several hundred kΩ, and even if the contact resistance between the second electrode pair 11 and the human body is about 100 to 1 kΩ. The setting is not affected.
[0014]
Next, the operation of each component will be described. The user inputs the individual information to the human body individual information means 13 for inputting information for each individual such as the sex, age, height, weight, etc. of the human body, grasps the hand electrode portion 15 and puts it on the foot electrode portion 16. Get on and touch the human body with the electrodes. A constant high-frequency current is applied to the human body by the constant current applying means 9 and the human body impedance is measured by the measuring means 12. In the control means 14, the height and weight of the individual information set by the human body individual information means 13 and the "correlation formula between human body impedance and body density" obtained in advance by a statistical method from the measured human body impedance. Then, the body fat percentage is calculated, and the body fat percentage is reported to the user by a notifying means (not shown).
[0015]
As a method for calculating the body fat percentage, the Brozek formula is generally known. From the relationship between the human body impedance and the body density, the body fat percentage = ((4.570 / body density) −4.412) × 100. Furthermore, the calculation formulas are divided and used in order to further increase the correlation with the body density depending on sex, age, and the like.
[0016]
Here, the relationship between the human body and the contact resistance between the first electrode pair 10 and the second electrode pair 11 and the human body impedance measurement will be described. The input terminal of the differential amplifier 19 connected to the second electrode pair 11 has a high input impedance of about several hundreds kΩ, and the contact resistance of about 100 to 1 kΩ between the second electrode pair 11 and the human body has little influence. However, when the contact resistance between the first electrode pair 10 and the human body is large, the human body itself is susceptible to power supply hum noise from other devices having an AC power supply unit. In particular, when the contact resistance is large, as shown in FIG. 5B, the human body resistance potential difference signal from the second electrode pair 11 to the measuring means 12 is the frequency f of the high-frequency current in the constant current applying means 9. The signal is a signal in which 50 Hz or 60 Hz of the power supply hum noise is superimposed, and the voltage measurement range of the measuring means 12 is exceeded (indicated by a dotted line) depending on the degree of the power hum noise superposition. During the period (T1) in which the human body resistance potential difference signal does not exceed the voltage measurement range of the measuring means 12, noise other than the applied frequency f of the high frequency signal generator 17 is supplied to the filter unit 20 even when power supply hum noise is superimposed. Although the hum noise is cut, the amplitude of the human resistance potential difference signal is reduced during the period (T2, T3) when the human resistance potential difference signal exceeds the voltage measurement range of the measuring means 12, and an accurate human resistance potential difference signal can be detected. Therefore, accurate human body impedance cannot be measured.
[0017]
In general, as the physiological sweating of the human body, there are thermal sweating for body temperature regulation such as sweating when the temperature is high, and mental sweating such as sweating when you are surprised, moved, or nervous. is there. Mental sweating occurs in addition to thermal sweating on the palms and soles of the whole body, and only thermal sweating occurs in other parts. For this reason, the palm and the sole of the foot are more likely to sweat than the other surface of the human body, and the contact resistance between the human body surface and the electrode is reduced.
[0018]
In this reference example, the human body impedance is measured by the palm and the sole of the foot, and the palm is gripped by the hand electrode portion 15 and the sole of the foot is placed on the foot electrode portion 16 in the measurement. The contact resistance between the palm and each electrode part on the sole of the foot is the contact resistance between the sole of the foot and the foot electrode part 16 because the foot electrode part 16 takes the weight of the human body as compared with the gripping force for gripping the hand electrode part 15. Becomes smaller. Therefore, by arranging the electrode 10b connected to the reference potential side of the constant current applying means 9 in the first electrode pair 10a, 10b for measuring the human body impedance on the back side of the foot, the human body itself can supply the AC power source. Therefore, it becomes difficult to receive power supply hum noise from other devices having a section, the human body resistance potential is stabilized, and accurate human body impedance can be measured.
[0019]
(Reference Example 2)
FIG. 6 is an external view of the biological information measuring apparatus according to the second reference example of the present invention. As shown in the figure, the biological information measuring apparatus of the present reference example includes a first electrode pair 25 including electrodes 25a and 25b and a second electrode pair 26 including electrodes 26a and 26b on the toilet seat 22 and the main body 23 side. It is provided in the hand electrode part 24 provided in the part.
[0020]
In the present reference example, the electrode corresponding to the first electrode pair 10b connected to the reference potential side of the constant current applying means 9 of the reference example 1 is arranged on the index finger side of the palm of the hand electrode portion 24 as the electrode 25b that contacts the right hand. Other parts having the same configuration and the same function and effect are the same as those in Reference Example 1, and detailed description thereof is omitted.
[0021]
With the above configuration, the human body impedance is measured with the hand and thigh, and the electrodes 25b and 26b come into contact with the palm of the hand by gripping the hand electrode unit 24 with the hand. By sitting on the toilet seat 22 in an exposed state, the thigh comes into contact with the electrodes 25 a and 26 a arranged on the toilet seat 22. The contact resistance between the thigh and the electrodes 25a and 26a becomes unstable due to changes in how the weight of the human body is applied to the electrodes depending on how the operator sits on the toilet seat 22 and the posture of the upper body. The sweat glands of the human body are distributed in the nectar in the palm, but the sweat glands of the thigh are less than the palm, and the contact resistance between the thigh and the electrodes 25a and 26a provided on the toilet seat 22 is more than that of the palm. growing. Therefore, by placing the electrode 25b connected to the reference potential side of the constant current applying means on the palm side of the first electrode pair 25a, 25b for measuring the human body impedance, the human body itself has an AC power source. Therefore, it becomes difficult to receive power supply hum noise from other devices, and the human body resistance potential is stabilized, and accurate human body impedance can be measured.
[0022]
(Reference Example 3)
FIG. 7A is an external view of the biological information measuring apparatus according to the third reference example . As shown in the figure, the biological information measuring apparatus of the present reference example has an arm electrode portion 27 and a hand electrode portion 28 connected by a lead wire 29. The arm electrode portion 27 is wound around and fixed to one arm of the user by a winding fixing portion 30 such as Velcro (registered trademark). In addition, the electrode 31 a in the first electrode pair 31 and the electrode 32 a in the second electrode pair 32 are disposed on the surface of the arm electrode portion 27 that contacts the user's skin. In the hand electrode portion 28, an electrode 31b in the first electrode pair 31 and an electrode 32b in the second electrode pair 32 are arranged. As shown in FIG. 7B, the arm electrode part 27 is wound around one arm and the hand electrode part 28 is grasped with the other hand.
[0023]
In the present reference example, the electrode corresponding to the electrode 10b of the first electrode pair 10 connected to the reference potential side of the constant current applying means 9 of the reference example 1 is disposed on the index finger side of the palm as the electrode 31b of the hand electrode portion 28. The other parts having the same configuration and the same function and effect are the same as those in Reference Example 1, and detailed description thereof is omitted.
[0024]
With the above configuration, the human body impedance is measured with the hand and the arm. At the time of measurement, the arm electrode portion 27 is wound around the arm, and the hand electrode 28 is gripped with the hand. The contact resistance with the arm electrode part 27 of the arm is unstable because the contact resistance between the electrode and the skin surface of the arm changes depending on how the wrapping and fixing part 30 such as a velcro tape is wound and how the arm skin is dried. Become a thing. The sweat glands of the human body are distributed in nectar on the palm, but the sweat glands on the surface of the arm are smaller than the palm, and the contact resistance between the arm and the arm electrode portion 27 is larger than the palm. Therefore, the first electrode 31b connected to the reference potential side of the constant current applying means 9 in the first electrode pair 31 for measuring the human body impedance is arranged on the palm side, so that the human body itself can supply the AC power supply. Therefore, it becomes difficult to receive power supply hum noise from other devices having a section, the human body resistance potential is stabilized, and accurate human body impedance can be measured.
[0025]
(Example 1 )
FIG. 8A is an external view of the biological information measuring apparatus according to the first embodiment of the present invention. As shown in the figure, in the biological information measuring apparatus of the present embodiment, a finger electrode portion 33 and a hand electrode portion 34 that are in contact with a finger of one hand are integrally formed. In addition, the electrode 35a of the first electrode pair 35 and the electrode 36a of the second electrode pair 36 are disposed on the surface of the finger electrode unit 33 that is touched by the user's finger. The electrode 35b in the first electrode pair 35 and the electrode 36b in the second electrode pair 36 are arranged. As shown in FIG. 8B, the use state is such that the finger electrode portion 33 is sandwiched between the fingers of one hand and the hand electrode portion 34 is gripped by the other hand.
[0026]
In this embodiment, the electrode corresponding to the first electrode pair 10b connected to the reference potential side of the constant current applying means 9 of Reference Example 1 is arranged as the electrode 35b of the hand electrode portion 34 on the index finger side of the palm. The other parts having the same configuration and the same function and effect are the same as those in Reference Example 1, and detailed description thereof is omitted.
[0027]
With the above configuration, the human body impedance is measured with the fingers of one hand and the palm of the other hand, and at the time of measurement, the finger of one hand sandwiches the finger electrode portion 33 and the hand electrode portion with the palm of the other hand 34. The contact resistance between the finger of one hand and the finger electrode portion 33 is determined by the contact strength between the finger of one hand (the force of pinching the finger) and the degree of dryness of the skin of the finger. The resistance changes and becomes unstable. In addition, the sweat glands of the human body are distributed in nectar in the palm, but the sweat glands on the surface of the finger are less than the palm and the contact area with the electrode is also smaller than the palm, so the fingers and finger electrodes of the hand The contact resistance with the part 33 becomes larger than the palm. Therefore, the first electrode 35b connected to the reference potential side of the constant current applying means 9 in the first electrode pair 35 for measuring the human body impedance is arranged on the palm side, so that the human body itself can supply the AC power supply unit. Therefore, it is difficult to receive power supply hum noise from other devices having the above, and the human body resistance potential is stabilized, and accurate human body impedance can be measured.
[0028]
( Reference Example 4 )
FIG. 9A is an external view of a biological information measuring apparatus according to a fourth reference example of the present invention. As shown in the figure, in the biological information measuring device of the present invention, a finger electrode portion 37 and a wrist electrode portion 38 that are in contact with a finger of one hand are integrally formed. Further, the wrist electrode portion 38 is fixed by being wound around one wrist of the user by a winding fixing portion 39 such as a magic tape. In addition, the electrode 40 a in the first electrode pair 40 and the electrode 41 a in the second electrode pair 41 are arranged on the surface of the finger electrode portion 37 that contacts the user's finger. In the wrist electrode portion 38, an electrode 40b in the first electrode pair 40 and an electrode 41b in the second electrode pair 41 are arranged. As shown in FIG. 9B, the use state is such that the finger electrode portion 37 is sandwiched between the fingers of one hand and the wrist electrode portion 38 is wound around the other wrist.
[0029]
In this reference example, the electrode corresponding to the first electrode pair 10b connected to the reference potential side of the constant current applying means 9 of Reference Example 1 is arranged on the finger side as the electrode 40a of the finger electrode portion 37. The other parts having the same configuration and the same function and effect are the same as those in Reference Example 1, and detailed description thereof is omitted.
[0030]
With the above configuration, the human body impedance is measured with the finger of one hand and the wrist of the other hand, and at the time of measurement, the finger of one hand sandwiches the finger electrode part 37 and the wrist electrode part is placed on the other wrist 38 is to be wound. The contact resistance of the wrist with the wrist electrode portion 38 is unstable because the contact resistance between the electrode and the skin surface of the wrist changes depending on how the wrapping fixing portion 39 such as a magic tape is wound or the degree of dryness of the skin of the wrist. Become a thing. In addition, the sweat glands of the human body are distributed in nectar on the palm, and the sweat glands on the surface of the finger are also distributed in large numbers, but there is little sweat gland distribution on the surface of the wrist skin, and the wrist and the wrist electrode part 38 The contact resistance is larger than the finger of the hand. Therefore, by placing the electrode 40a connected to the reference potential side of the constant current applying means 9 in the first electrode pair 40 for measuring the human body impedance on the finger side of the hand, the human body itself has the AC power supply unit. It becomes difficult to receive power supply hum noise from other devices, etc., and the human body resistance potential is stabilized, and accurate human body impedance can be measured.
[0031]
【The invention's effect】
As described above, according to the first aspect of the present invention, the first electrode connected to the reference potential side of the constant current means for applying the high-frequency current to the human body is the contact resistance between the human body and the first electrode pair. Since the human body itself is less susceptible to power supply hum noise from other devices having an AC power supply unit, the human body resistance potential is stable, and accurate human body impedance can be measured. .
[Brief description of the drawings]
FIG. 1 is a configuration diagram of a biological information measuring device in Reference Example 1 of the present invention. FIG. 2 (a) Connection diagram of electrodes and hands of the biological information measuring device in Reference Example 1 of the present invention. FIG. 3 is an internal circuit diagram of constant current application means in Reference Example 1 of the present invention. FIG. 4 is an internal circuit diagram of measurement means in Reference Example 1 of the present invention. 5A is a waveform diagram of a human body resistance potential signal. FIG. 5B is a waveform diagram when power supply hum noise is superimposed on a human body resistance potential signal. FIG. 6 is an external view of a biological information measuring apparatus according to Reference Example 2 of the present invention. 7 (a) of the connection diagram of the biological information measuring device and the human body in reference example 3 of an external view of a biological information measuring device (b) the present invention in reference example 3 of the invention [8] (a) the present invention external view of a biological information measuring apparatus in embodiment 1 (b) real of the present invention Connection diagram with the biological information measuring device and the human body in the example 1 [9] (a) Reference Example external view of a biological information measuring apparatus according to 4 (b) the biological information measuring device and the human body in Reference Example 4 of the present invention of the present invention [Fig. 10] Configuration diagram of a conventional biological information measuring device [Fig. 11] External view of a conventional body fat percentage meter [Explanation of symbols]
9 Constant current applying means 10, 25, 31, 35, 40 First electrode pair 11, 26, 32, 36, 41 Second electrode pair 12 Measuring means 13 Human body individual information means 14 Control means

Claims

基準電位から人体抵抗に応じて印加電圧を変えて一定の電流を人体の測定部位間に印加する定電流印加手段と、人体の測定部位間に前記定電流印加手段により高周波電流を印加する第１の電極対と、この高周波電流の身体通電経路内に配置して人体抵抗電位を測定する第２の電極対と、前記第１の電極対間に流れる高周波電流と前記第２の電極対間の人体抵抗電位により人体インピーダンスを計測する計測手段と、人体の個人別情報を入力する人体個別情報手段と、前記人体インピーダンスと前記人体の個人別情報により体脂肪率等の生体情報を算出する制御手段とを備え、前記第１の電極対の内、定電流印加手段の基準電位側の電極は、人体との接触抵抗が低くなる部位に配置するもので、第１の電極対は、人体の一方の手の指で挟み込まれる指電極部と、人体の他方の手で握られる手電極部とにそれぞれ配設され、定電流印加手段の基準電位側の電極を手電極部に配設したことを特徴とした生体情報測定装置。 A constant current applying means for changing a voltage applied from a reference potential in accordance with the human body resistance to apply a constant current between the measurement parts of the human body, and a first application of a high frequency current between the measurement parts of the human body by the constant current application means. An electrode pair, a second electrode pair that is disposed in the body energization path of the high-frequency current and measures a human body resistance potential, and a high-frequency current that flows between the first electrode pair and the second electrode pair Measuring means for measuring human body impedance by human body resistance potential, human body individual information means for inputting personal information of the human body, and control means for calculating biological information such as body fat ratio by the human body impedance and personal information of the human body Among the first electrode pairs, the electrode on the reference potential side of the constant current applying means is arranged at a part where the contact resistance with the human body is low, and the first electrode pair is one of the human body Sandwiched between fingers The finger electrode portions that are respectively disposed in the hand electrode portion to be held in the body of the other hand, the biological information measurement characterized in that disposed in the hand electrode portion reference potential side electrode of constant current applying means Equipment .