JP3777802B2

JP3777802B2 - Temperature detection device

Info

Publication number: JP3777802B2
Application number: JP18184298A
Authority: JP
Inventors: 実紀森口; 博久今井; 直史中谷; 弘文乾; 加寿子粟屋
Original assignee: Panasonic Corp; Matsushita Electric Industrial Co Ltd
Current assignee: Panasonic Corp; Panasonic Holdings Corp
Priority date: 1998-06-29
Filing date: 1998-06-29
Publication date: 2006-05-24
Anticipated expiration: 2018-06-29
Also published as: JP2000009538A

Description

【０００１】
【発明の属する技術分野】
本発明は非接触で対象物の温度を検出する温度検出装置に関し、特に赤外線の入光と遮光を制御する遮光板に関するものである。
【０００２】
【従来の技術】
従来より非接触で対象物の温度を検出する温度検出装置として焦電型赤外線検出器を用いたものにおいては、赤外線検出器に入射する赤外光の入光と遮光を切り替える遮光板が設けられている。この遮光板は例えば金属板のように赤外線を透過しない材料で構成し、その端部を直流モータや交流モータの回転軸に取り付け回転駆動させ、赤外線検出器に至る赤外光の入光と遮光を繰り返し断続させるという方法がある。即ち図１１に示すように半円弧状の遮光板１を直流または交流モータ２の回転軸に取り付けて矢印の方向に回転駆動することで赤外線検出器３に入射する赤外光を断続する。
【０００３】
またパルスモータを回転駆動源として所定周期でパルス印加し、所定角度を例えば正転と反転を繰り返すことで赤外光を断続させる方法もある。例えば特開平７−２８０６５２号公報に示す温度測定装置の例を図１２を参照しながら説明する。チョッパ（遮光板）１はパルスモータと同様の原理による駆動源である水晶時計ムーブメント４により往復運動するように駆動され、赤外線検出器３に至る赤外光を断続する。水晶時計ムーブメント４は永久磁石５と、コア６とコイル７を含み、永久磁石５にはチョッパ１の端部を取り付けている。コイル７は第１および第２の入力端子８、９にパルス入力を受け取り、このパルス入力に応答して永久磁石５が回動し、チョッパ１が矢印に示すように往復運動する。
【０００４】
【発明が解決しようとする課題】
しかしながら、直流モータを駆動源として遮光板を回転させる上記従来例の場合には入光時間、遮光時間のばらつきにより、温度測定精度が低いという課題がある。直流モータは一般に電源電圧の変動等の原因で回転数が変動する。回転数が変動すれば入光、遮光の周期が変わり、この周期の変動により赤外線検出器の出力も変動して正確な温度検出ができない。回転数を安定させるためには、フォトインタラプタ等の回転数を検出する手段と電源電圧を調整する手段を設け、フィードバック制御を行うような複雑な制御回路が必要となる。
【０００５】
また交流モータを駆動源とした場合には、商用電源のように比較的安定した周波数のもとでは直流モータより回転数を安定させ易いが、商用電源のような交流電源を必要とするという課題がある。これは携帯型の放射温度計や放射体温計のように電池電源で構成する場合には直流電源しかなく、安定した周波数の交流電源を作るための複雑な回路が必要となり実現が困難である。
【０００６】
また水晶時計ムーブメントやパルスモータを駆動源とした場合にはマイクロプロセッサ等のデジタル信号を基に駆動するので、入光、遮光の周期は高い精度で断続できるが、遮光板が揺動しながら停止するために入光、遮光を精度よく切り替えることが困難であるという課題がある。即ちこれら駆動源は磁力による吸引力と反発力のバランスで停止し、磁力の極性を変えることで駆動するものであるから、停止の瞬間に遮光板は揺動しながら吸引力と反発力をバランスさせて停止するという特性がある。
【０００７】
図１３にパルスモータの挙動の特性を示す。横軸は経過時間であり、（ａ）は駆動パルスで一定周期ｔ、デューティ５０％でＣＷ（時計方向）とＣＣＷ（反時計方向）のパルスを交互に出力している。（ｂ）がパルスモータの回転軸の回転角度で図のように停止位置に到達する時点でオーバーシュートを起こし、その後アンダーシュートを起こし、その振幅は小さくなりながら停止位置で安定する。
【０００８】
パルスモータや水晶時計ムーブメントは一般に図１３に示すような挙動の特性を持つものであるために、これらを遮光板の駆動源として赤外光を断続すると、入光から遮光、または遮光から入光に切り替わる瞬間に非常に短い間隔で入光と遮光が切り替わる状況が発生し、そのために赤外線検出器の出力は不安定になり、温度検出の正確さを欠くという課題がある。この課題を回避するためには、揺動の最大位置であるΔθに対して十分大きい遮光板の形状にする方法があるが、この場合には温度検出装置自体も大型化してしまうという課題がある。
【０００９】
【課題を解決するための手段】
本発明は上記課題を解決するために、被測定物が放射する赤外線を検出する赤外線検出器と、前記赤外線検出器に入射する赤外線を遮光する遮光板と、前記遮光板を駆動する直流モータと、前記遮光板の停止位置を決めるストッパと、前記直流モータを制御するモータ制御手段と、前記赤外線検出器の出力を基に被測定物の温度を換算する温度換算手段と、温度検出開始信号を発信する発信手段とを有し、前記モータ制御手段は、前記直流モータを駆動して前記遮光板の位置合わせを行う位置合わせ駆動手段と、前記直流モータの回転方向を交互に反転させて前記赤外線検出器に至る赤外線光路の入光と遮光を切り替えて温度検出を行う温度検出駆動手段と、前記位置合わせ駆動手段と前記温度検出駆動手段を切り替える切替手段と、前記発信手段からの温度検出開始信号が非受信状態である連続時間を計時する計時手段を有し、前記計時手段が所定の時間を計時する前に発信手段からの温度検出開始信号を受信すると切替手段が温度検出駆動手段を動作させ、前記計時手段が所定の時間を計時した後に発信手段からの温度検出開始信号を受信すると切替手段が位置合わせ駆動手段を動作させた後に温度検出駆動手段を動作させるものである。
【００１０】
上記発明によれば、計時手段が発信手段からの温度検出開始信号が非受信状態である連続時間を計時し、計時手段が所定の時間を計時する前に温度検出開始信号を受信すると、切替手段が温度検出駆動手段を動作させ、温度検出駆動手段は直流モータの回転方向を交互に反転させて遮光板をストッパに衝突させて停止させ、赤外線検出器に至る赤外線光路の入光と遮光を切り替え、赤外線検出器が被測定物の放射する赤外線を検出し、温度換算手段が赤外線検出器の出力を基に被測定物の温度を換算する。そして、計時手段が所定の時間を計時した後に発信手段からの信号を受信すると、切替手段が位置合わせ駆動手段を動作させ、位置合わせ駆動手段が直流モータを駆動して遮光板をストッパに衝突させて遮光板の位置合わせを行った後、切替手段が温度検出駆動手段を動作させて温度検出を行う。従って、遮光板の位置合わせにより温度検出開始時に遮光板を常に同じ位置にすることができ、温度検出時に遮光板の駆動による入光時間、遮光時間を安定させることができる。そして遮光板は停止位置での揺動も起こさないので、遮光板は十分小型にしても入光と遮光の状態を安定して切り替えることができ、小型で精度の高い温度検出を行うことができる。また、温度検出時の遮光板の最終の停止位置から位置ずれを起こさないことが想定されるような短時間で繰り返して温度検出を行う場合は遮光板の位置合わせを行わずに続けて温度検出を行うことができるので、短時間で、精度の高い温度検出を行うことができ、また、長時間にわたり温度検出を行わず放置されている間に遮光板の位置がずれてしまった場合でも、再度温度検出を行う場合は遮光板の位置合わせを行った後温度検出を行うので、常に精度の高い温度検出を行うことができる。
【００１１】
【発明の実施の形態】
本発明の請求項１にかかる温度検出装置は、被測定物が放射する赤外線を検出する赤外線検出器と、前記赤外線検出器に入射する赤外線を遮光する遮光板と、前記遮光板を駆動する直流モータと、前記遮光板の停止位置を決めるストッパと、前記直流モータを制御するモータ制御手段と、前記赤外線検出器の出力を基に被測定物の温度を換算する温度換算手段と、温度検出開始信号を発信する発信手段とを有し、前記モータ制御手段は、前記直
流モータを駆動して前記遮光板の位置合わせを行う位置合わせ駆動手段と、前記直流モータの回転方向を交互に反転させて前記赤外線検出器に至る赤外線光路の入光と遮光を切り替えて温度検出を行う温度検出駆動手段と、前記位置合わせ駆動手段と前記温度検出駆動手段を切り替える切替手段と、前記発信手段からの温度検出開始信号が非受信状態である連続時間を計時する計時手段を有し、前記計時手段が所定の時間を計時する前に発信手段からの温度検出開始信号を受信すると切替手段が温度検出駆動手段を動作させ、前記計時手段が所定の時間を計時した後に発信手段からの温度検出開始信号を受信すると切替手段が位置合わせ駆動手段を動作させた後に温度検出駆動手段を動作させるものである。
【００１２】
そして、計時手段が発信手段からの温度検出開始信号が非受信状態である連続時間を計時し、計時手段が所定の時間を計時する前に温度検出開始信号を受信すると、切替手段が温度検出駆動手段を動作させ、温度検出駆動手段は直流モータの回転方向を交互に反転させて遮光板をストッパに衝突させて停止させ、赤外線検出器に至る赤外線光路の入光と遮光を切り替え、赤外線検出器が被測定物の放射する赤外線を検出し、温度換算手段が赤外線検出器の出力を基に被測定物の温度を換算する。そして、計時手段が所定の時間を計時した後に発信手段からの信号を受信すると、切替手段が位置合わせ駆動手段を動作させ、位置合わせ駆動手段が直流モータを駆動して遮光板をストッパに衝突させて遮光板の位置合わせを行った後、切替手段が温度検出駆動手段を動作させて温度検出を行う。従って、遮光板の位置合わせにより温度検出開始時に遮光板を常に同じ位置にすることができ、温度検出時に遮光板の駆動による入光時間、遮光時間を安定させることができる。そして遮光板は停止位置での揺動も起こさないので、遮光板は十分小型にしても入光と遮光の状態を安定して切り替えることができ、小型で精度の高い温度検出を行うことができる。また、温度検出時の遮光板の最終の停止位置から位置ずれを起こさないことが想定されるような短時間で繰り返して温度検出を行う場合は遮光板の位置合わせを行わずに続けて温度検出を行うことができるので、短時間で、精度の高い温度検出を行うことができ、また、長時間にわたり温度検出を行わず放置されている間に遮光板の位置がずれてしまった場合でも、再度温度検出を行う場合は遮光板の位置合わせを行った後温度検出を行うので、常に精度の高い温度検出を行うことができる。
【００１３】
また、本発明の請求項２にかかる温度検出装置は、被測定物が放射する赤外線を検出する赤外線検出器と、前記赤外線検出器に入射する赤外線を遮光する遮光板と、前記遮光板を駆動する直流モータと、前記遮光板の停止位置を決めるストッパと、前記直流モータを制御するモータ制御手段と、前記赤外線検出器の出力を基に被測定物の温度を換算する温度換算手段と、温度検出開始信号を発信する発信手段とを有し、前記モータ制御手段は、前記直流モータを駆動して前記遮光板の位置合わせを行う位置合わせ駆動手段と、前記直流モータの回転方向を交互に反転させて前記赤外線検出器に至る赤外線光路の入光と遮光を切り替えて温度検出を行う温度検出駆動手段と、前記位置合わせ駆動手段と前記温度検出駆動手段を切り替える切替手段と、前記発信手段からの温度検出開始信号が非受信状態である連続時間を計時する計時手段を有し、前記切替手段はモータ制御手段に電源が投入された時および、前記計時手段が所定の時間を計時する毎に位置合わせ駆動手段を動作させ、前記発信手段からの温度検出開始信号を受信した時に温度検出駆動手段を動作させることにより、温度検出開始時に前記遮光板は常に同じ位置にあることを特徴とする温度検出装置とする。
【００１４】
そして、切替手段はモータ制御手段に電源が投入された時に位置合わせ駆動手段を動作させて遮光板の位置合わせを行い、そして、計時手段が発信手段からの温度検出開始信号が非受信状態である連続時間を計時し、所定の時間を計時する毎に定期的に切替手段が位置合わせ駆動手段を動作させて遮光板の位置合わせを行い、温度検出開始信号を受信した時に温度検出駆動手段を動作させて温度検出を行うので、短時間で繰り返して温度検出を行う場合は遮光板の位置合わせを行わずに続けて温度検出を行うことができるので、短
時間で精度の高い温度検出を行うことができ、また、長時間にわたり温度検出を行わず放置されている間に遮光板の位置がずれてしまった場合でも、計時手段が所定の時間を計時する毎に定期的に遮光板の位置合わせを行うので、常に精度の高い温度検出を行うことができる。
【００１５】
【実施例】
（実施例１）
以下、本発明の実施例を図１〜図３を参照しながら説明する。図１は本発明の実施例として温度検出装置を体温計に搭載した応用例の構成ブロック図である。また、図２は遮光板部の要部拡大図であり、図３は直流モータの制御方法を示すタイミングチャートである。
【００１６】
一般に表面温度を計測する体温計としては、鼓膜や口腔、肛門など外気に接触しにくい部分の温度を計測することでほぼ体温を計測できる。特に鼓膜は体温を制御する視床下部が近いこともあり、体温計測として適切な場所として知られている。図１において、１０は温度を測定すべき被測定物で例えば鼓膜である。１１は耳孔に挿入するプロ
ーブで先端にいくに従って径を細くして耳孔に挿入しやすい形状としている。１２は鼓膜１０から放射される赤外線を集光するレンズで、３はレンズ１２で集光された赤外線を検出する焦電型の赤外線検出器で、感知する赤外線量の微分値に相関を持って出力が変化する。また、１は赤外線検出器３に入射する赤外線を遮光する遮光板、２は遮光板１を駆動する直流モータ、１３は遮光板１の停止位置に設け遮光板１を停止させるストッパ、１４は直流モータ２を制御するモータ制御手段、１５はモータ制御手段１４に温度検出開始信号１５ａを発信する発信手段で測定スイッチである。モータ制御手段１４は、直流モータ２を駆動して遮光板１の位置合わせを行う位置合わせ駆動手段１６、温度検出時に直流モータ２の回転方向を交互に反転させる温度検出駆動手段１７、位置合わせ駆動手段１６と温度検出駆動手段１７を切り替える切替手段１８とを有している。また、１９は赤外線検出器３自身の温度を検出する温度センサで、サーミスタによるものである。２０は赤外線検出器３で出力される電圧を増幅する増幅器、２１は増幅器２０の出力と温度センサ１９の出力をアナログ値からデジタル値に変換するＡＤ変換器、２２はＡＤ変換器２１の出力に基づき、温度に換算する温度換算手段、２３は温度換算手段２２で算出された温度を表示する表示手段である。
【００１７】
上記構成において、体温を測定する場合、プローブ１１を耳孔部に挿入して、温度検出開始信号１５ａを発信する測定スイッチ１５を押す。モータ制御手段１４が温度検出開始信号１５ａを受信すると、切替手段１８はまず位置合わせ駆動手段１６を動作させ、位置合わせ駆動手段１６が直流モータ２を駆動して遮光板１の位置合わせを行う。その後、切替手段１８が温度検出駆動手段１７に切り替え、温度検出駆動手段１７は直流モータ２の回転方向を交互に反転させる。この直流モータ２の回転により遮光板１は停止位置に設けられたストッパ１３の間で往復回動を繰り返し、鼓膜１０から赤外線検出器３に至る赤外線光路を断続し、入光と遮光を切り替える。ここで、遮光板１は金属により構成していて、遮光しているときは赤外線検出器３自身が放射する赤外線が金属面で反射して赤外線検出器３に入光するので、遮光板１の断続動作により、鼓膜１０から放射される赤外線と赤外線検出器３自身が放射する赤外線とが交互に赤外線検出器３で検出される。赤外線検出器３は焦電型で、感知する赤外線量の微分値に相関を持って出力が変化するので、赤外線検出器３の出力は鼓膜１０と赤外線検出器３の温度差と相関を持っている。従って、温度換算手段２２はこの関係を用いて鼓膜１０の温度を換算する。即ち、赤外線検出器３の出力を増幅器２０で増幅し、増幅器２０で増幅した出力電圧と温度センサ１９の出力電圧をＡＤ変換器２１でデジタル化し、ＡＤ変換器２１の出力を基に温度換算手段２２が鼓膜１０の温度を換算する。そして、表示手段２３に温度を表示する。
【００１８】
次に図２、図３を用いて遮光板１の位置合わせ駆動及び温度検出駆動について詳しく説明する。図２の遮光板部の拡大図において、ストッパ１３は、遮光板１が赤外線検出器３を遮光する遮光状態で停止するときに接する遮光停止部１３ａと、入光状態で停止するときに接する入光停止部１３ｂとからなっており、直流モータ２の回転により、シャフト２４に取り付けられた遮光板１が、遮光停止部１３ａと入光停止部１３ｂの間を移動する。図中、遮光板１が遮光状態で停止している状態を実線で示し、入光状態で停止している状態を破線で示している。
【００１９】
上記構成において、測定スイッチ１５が押され、モーター制御手段１４が温度検出開始信号１５ａを受信すると、切替手段１８はまず、位置合わせ駆動手段１６を動作させて遮光板１の位置合わせを行う。即ち図３に示すように、位置合わせ駆動手段１６は温度検出開始信号１５ａの受信からｔ１時間直流モータ２に電力を供給し、遮光板１を図２に示す遮光方向に回転させる。ここでｔ１は遮光板が赤外線の入光状態で停止している状態（破線）から遮光状態で停止する状態（実線）に移動するのに要する時間より長い時間とする。これにより、モータ制御手段１４が温度検出開始信号１５ａを受信する以前に、遮光板１が遮光停止部１３ａと入光停止部１３ｂの間のどの位置に停止していたとしても、遮光板１を遮光停止部１３ａに衝突させて、常に遮光状態で停止させることができ、遮光板１の位置合わせを行うことができる。
【００２０】
そして、遮光板１の位置合わせを行った後、切替手段１８は温度検出駆動手段１７に切り替え、温度検出駆動手段１７は温度検出を行うために図３示すように直流モータ２に電力を供給し、遮光板１を駆動する。即ち、初めにｔ1時間電力を供給して遮光板１を入光方向に回転させ、入光停止部１３ｂに衝突停止させ、その後のｔ2時間は断続的に電力を供給して停止位置すなわち入光状態で遮光板１を保持する。そしてさらに、次のｔ1時間は逆方向に電力を供給して遮光板１を遮光方向に回転させ、遮光停止部１３ａに衝突停止させ、そしてｔ2時間は断続的に電力を供給し、停止位置すなわち遮光状態で遮光板１を保持する。このようにして、温度検出駆動手段１７は直流モータ２を交互に反転させることにより、遮光板１による赤外線検出器３に至る赤外線の入光と遮光を繰り返し、最後は、遮光状態で終了させるものとする。
【００２１】
ここで、温度検出駆動手段１７が作動中の赤外線検出器３の出力は、遮光板１による赤外線の断続動作により図３に示すように交流波形となり、この交流波形の振幅Ｖが鼓膜１０の温度と赤外線検出器３の温度の４乗の差に比例している。従って、温度換算手段２２はこの関係に基づき、振幅Ｖと温度センサ１９が検出する赤外線検出器３の温度から鼓膜１０の温度を逆算し、そしてさらに、入光と遮光とを繰り返すことにより得られる複数の温度を平均化して鼓膜１０の温度としている。このように入光と遮光を繰り返して複数のデータを平均化することにより、ノイズ等の影響を低減することが可能となり、温度測定精度を向上させることができる。なお、遮光板１を駆動して入光と遮光を複数回繰り返したが、１回だけの入光と遮光で温度を換算しても良く、その場合、温度検出時間を短縮することができる。
【００２２】
以上、本実施例によると、切替手段１８が位置合わせ駆動手段１６と温度検出駆動手段１７を切り替え、位置合わせ駆動手段１６が遮光板１の位置合わせを行った後、温度検出駆動手段１７が直流モータ２の回転方向を交互に反転させて遮光板１により赤外線の入光と遮光を切り替えて温度検出を行うので、温度検出開始時に遮光板１を常に同じ位置にすることができ、温度検出時の遮光板１の駆動による入光時間、遮光時間を安定させることができ、精度の高い温度検出を行うことができる。
【００２３】
そして、直流モータ２によって駆動する遮光板１を停止位置に設けたストッパ１３に衝突させることによって、遮光板１を赤外線の入光と遮光のそれぞれの状態で停止させるこ
とができ、遮光板の停止位置での揺動も起こさないので、遮光板１は十分小型にしても入光と遮光の状態を安定して切り替えることができ、小型で精度の高い温度検出を行うことができる。
【００２４】
また、赤外線を遮光する停止位置で温度検出のための遮光板１の駆動を終了させることにより、非温度検出時に埃やゴミで赤外線検出器３が汚れるのを防ぐことができ、温度検出精度を保つことができる。
【００２５】
さらに、本実施例では、位置合わせ駆動手段１８が、赤外線検出器３に至る赤外線を遮光する位置まで遮光板１を駆動して位置合わせを行っているが、これは、温度検出駆動手段１９による遮光板１の駆動の回数を最も効率良くする効果がある。すなわち、温度検出時の赤外線検出器３の出力振幅Ｖが大きいほど、ノイズの影響を受け難く、温度精度を良くすることができるので、入光と遮光、または、遮光と入光の組合わせで出力振幅Ｖを得るのが良いと考えられ、入光と遮光、または、遮光と入光の組合わせで温度検出をするものとする。ここで、仮に位置合わせ駆動手段１８が、入光状態に遮光板１を駆動して位置合わせを行ったとすると、温度検出駆動手段１９は遮光板１を遮光状態に駆動するところから温度検出を開始し、入光状態で終了してしまうことになり、赤外線検出器３が非温度検出時に埃等で汚れないようにするためには、遮光板１を遮光状態にさらに駆動する必要があり、位置合わせ駆動手段１８が、遮光状態に遮光板１を駆動して位置合わせを行う場合に比べて、遮光板１の駆動回数が１回多くなってしまう。従って、位置合わせ駆動手段１８が、遮光板１を遮光状態に駆動して位置合わせを行うことにより、遮光板１を最も効率良く駆動できる。
（実施例２）
以下、本発明の第２の実施例を図４、図５を参照しながら説明する。図４は本発明の第２の実施例の温度検出装置を搭載した体温計の構成ブロック図で、図５は同実施例のモータ制御手段の動作を説明するフローチャート図である。
【００２６】
図４において、２５は測定スイッチ１５からの温度検出開始信号１５ａが非受信状態である連続時間を計時する計時手段、２６は計時手段２５が所定の時間を計時した時に時間経過フラグを記憶する記憶手段、２７は記憶手段２６に記憶される時間経過フラグの有無を判定して、切替手段１８のその後の動作を指示する判定手段である。なお、第１の実施例と同様の構成要素には同様の符号を付し、説明を省略する。
【００２７】
次に、モータ制御手段１４の動作を図５を用いて具体的に説明する。まず、モータ制御手段１４の電源が投入された時に記憶手段２６に初期状態として時間経過フラグが記憶され（Ｓ１００）、以下の動作を繰り返し行う。すなわち、Ｓ１０１にて計時手段２５が計時する時間が所定の時間ｔ３を経過していなければ記憶手段２６はそのままの状態にして温度検出開始信号１５ａの受信を待って待機し、計時手段２５が計時する時間が所定の時間ｔ３経過するとＳ１０２で記憶手段２６に時間経過フラグを記憶して、温度検出開始信号１５ａの受信を待って待機する。やがて、測定スイッチ１５が押され、モータ制御手段１４が温度検出開始信号１５ａを受信すると（Ｓ１０３）、判定手段２７が記憶手段２６に時間経過フラグが記憶されているかどうかをみに行く（Ｓ１０４）。ここで、時間経過フラグが記憶されていない場合、切替手段１８はすぐに温度検出駆動手段１７を作動させる（Ｓ１０６）。また、時間経過フラグが記憶されている場合は切替手段１８が位置合わせ駆動手段１６を作動させた後（Ｓ１０５）、続けて温度検出駆動手段１７に切り替えて作動させる（Ｓ１０６）。その後、計時手段２５をリセット駆動させて（Ｓ１０７）、さらに記憶手段２６に記憶されている時間経過フラグを消去して（Ｓ１０８）、最初に戻り、同じことを繰り返す。
【００２８】
上記構成によって、モータ制御手段１４の電源が投入された後、初めて温度検出を行う
場合は記憶手段２６に時間経過フラグが記憶されているので、遮光板１の位置合わせを行った後、温度検出を行うので、電源を切った状態で放置されている間に遮光板の位置がずれてしまった場合でも、精度の高い温度検出を行うことができる。そして、電源投入後回目以降の温度検出においては、連続して温度検出を行う場合や、所定の時間ｔ３を経過していない短時間で繰り返して温度検出を行う場合は、遮光板１の位置合わせを行わずに続けて温度検出を行うことができるので、短時間で、精度の高い温度検出を行うことができ、所定の時間ｔ３を経過して長時間温度検出を行わず放置されている間に遮光板１の位置がずれてしまった場合でも、再度温度検出を行う場合は遮光板１の位置合わせを行った後、温度検出を行うので、常に精度の高い温度検出を行うことができる。
【００２９】
（実施例３）
以下、本発明の第３の実施例を図６、図７、図８を参照しながら説明する。図６は本発明の第３の実施例の温度検出装置を搭載した体温計の構成ブロック図、図７は同実施例のモータ制御手段の動作を説明するフローチャート図で、図８は同実施例の電源制御手段の動作を説明する回路図である。図６において、２８は直流モータ２を制御するモータ制御手段１４の電源の投入と遮断を制御する電源制御手段で、測定スイッチ１５からの温度検出開始信号１５ａが非受信状態である連続時間を計時する計時手段２５を有している。なお、上述の実施例と同様の構成要素には同様の符号を付し、説明を省略する。
【００３０】
次に、モータ制御手段１４の動作を図７を用いて具体的に説明する。まず、電源制御手段２８により、モータ制御手段１４の電源が投入された時に、切替手段１８は位置合わせ駆動手段１６を作動させ遮光板１の位置合わせを行い（Ｓ２００）、同時に計時手段２５による計時を開始させる（Ｓ２０１）。モータ制御手段１４は計時手段２５が所定の時間ｔ３を計時するまで（Ｓ２０２）は温度検出開始信号１５ａの受信を待って待機しており、待機中測定スイッチ１５が押されて温度検出開始信号１５ａを受信すると（Ｓ２０３）、切替手段１８が温度検出駆動手段１７を作動させ、温度検出を開始する（Ｓ２０４）。その後、計時手段２５をセットして再び計時を開始し、同様のことを繰り返す。また、モータ制御手段１４が温度検出開始信号１５ａの受信を待って待機中に計時手段２５が所定の時間ｔ３を計時すると、電源制御手段２８がモータ制御手段１４の電源を遮断する（Ｓ２０５）。そして、モータ制御手段１４の電源が遮断された後に温度検出を行いたい時はモーター制御手段１４の電源の投入から再度やりなおすものである。
【００３１】
次に図８を用いて電源制御手段２８について説明する。電源制御手段２８はマイクロコンピュータ（以後マイコンと記す）２９と、直流電源である電池３０と、ＰＮＰ型のトランジスタ３１と、抵抗器３２、３３、３４と、ダイオード３５、３６と、電源スイッチ３７により構成している。図８において、電源スイッチ３７を押すと抵抗器３２、３３、ダイオード３５、電源スイッチ３７に電流が流れトランジスタ３１がオン状態となり、マイコン２９、モータ制御手段１４に電源が供給される。ここで、マイコン２９は出力端子２９aをロウにすることにより電源スイッチ３７が離されてもトランジスタ３１をオン状態で保持できて、マイコン２９、モータ制御手段１４に電源を供給し続けることができる。一方、電源スイッチ３７が押されている時はトランジスタ３１から抵抗器３４、ダイオード３６に電流が流れマイコン２９の入力端子２９bはロウを入力でき、離されればハイを入力できる。
【００３２】
一般的な使い方においては、電源スイッチ３７が押されるとマイコン２９は出力端子２９aをロウにして、マイコン２９、モータ制御手段１４に電源を供給し続ける。ここで、温度検出開始信号１５ａを発信する測定スイッチ１５が押されると抵抗器３８から測定スイッチ１５を電流が流れ、マイコン２９は入力端子２９cがロウになることで測定スイッチ１５が押されたことを検知して温度測定を行う。再度電源スイッチ３７が押されるとマイコン２９は出力端子２９aをハイにすることで、電源スイッチ３７が離された瞬間にマ
イコン２９、モータ制御手段１４の電源供給を停止できる。
【００３３】
また、使用者が再度電源スイッチ３７を押すことを忘れてマイコン２９、モータ制御手段１４に電源が供給され続けている場合には無駄な電池消耗を避けるためにマイコン２９は出力端子２９aをハイにして電源供給を停止することができる。それは、マイコン２９が計時手段２５を内蔵していて測定スイッチ１５が押されない連続時間を計時し、それが所定時間を超えたところで出力端子２９aをハイにすれば良い。
【００３４】
従って、本実施例によると、遮光板１の位置合わせをモータ制御手段１４の電源投入時に行うので、温度検出を短時間で行うことができる。そして、繰り返して温度検出を行う場合に、計時手段２５が所定の時間を計時するまでは、遮光板１の位置合わせを行わずに続けて温度検出を行うことができるので、短時間で精度の高い温度検出を行うことができ、長時間にわたり温度検出を行わず放置されて遮光板１の位置がずれてしまった場合でも、計時手段２５が所定の時間を計時し、モータ制御手段１４の電源は遮断されるので、再度温度検出を行う時にはモータ制御手段１４の電源を投入することで、切替手段１８が位置合わせ駆動手段１６を動作させて遮光板１の位置合わせを行い、その後の温度検出開始信号１５ａで温度検出を行うので、常に精度の高い温度検出を行うことができる。また、モータ制御手段１４の電源を切り忘れた場合でも、所定時間経過すると自動的に電源が遮断されるので、消費電力を低減させることができ、そして使い勝手が良くなる。
【００３５】
（実施例４）
以下、本発明の第４の実施例を図９、図１０を参照しながら説明する。図９は本発明の第４の実施例の温度検出装置を搭載した体温計の構成ブロック図で、図１０は同実施例のモータ制御手段の動作を説明するフローチャート図である。モータ制御手段１４の動作を図９、図１０を用いて具体的に説明する。まず、モータ制御手段１４の電源が投入されると、切替手段１８が位置合わせ駆動手段１６を作動させ遮光板１の位置合わせを行い（Ｓ３００）、そして計時手段２５による計時が開始される（Ｓ３０１）。モータ制御手段１４は計時手段２５が所定の時間ｔ３を計時するまで（Ｓ３０２）は温度検出開始信号１５ａの受信を待って待機しており、測定スイッチ１５が押されて温度検出開始信号１５ａを受信すると（Ｓ３０３）、切替手段１８が温度検出駆動手段１７を作動させ、温度検出を開始する（Ｓ３０４）。そして温度検出を開始後、計時手段２５はリセットされて（Ｓ３０５）、モータ制御手段１４は再び温度検出開始信号１５ａの受信を待つ待機状態となり、同様のことを繰り返す。そして待機中に、計時手段２５が所定の時間ｔ３を計時する毎に、切替手段１８が位置合わせ駆動手段１６を作動させ遮光板１の位置合わせを行う。
【００３６】
従って、本実施例によると、計時手段２５が測定スイッチ１５からの温度検出開始信号１５ａが非受信状態である連続時間を計時し、所定の時間を計時する毎に定期的に切替手段１８が位置合わせ駆動手段１６を動作させて遮光板１の位置合わせを行い、温度検出開始信号１５ａを受信した時に温度検出駆動手段１７を動作させて温度検出を行うので、連続して温度検出を行う場合は遮光板１の位置合わせを行わずに続けて温度検出を行うことができるので、短時間で精度の高い温度検出を行うことができ、また、長時間にわたり温度検出を行わず放置されている間に遮光板１の位置がずれてしまった場合でも、計時手段２５が所定の時間を計時する毎に定期的に遮光板１の位置合わせを行うので、常に精度の高い温度検出を行うことができる。
【００３７】
【発明の効果】
以上説明したように本発明の温度検出器は以下の効果を有する。
【００３８】
（１）遮光板の位置合わせにより温度検出開始時に遮光板を常に同じ位置にすることができ、温度検出時に遮光板の駆動による入光時間、遮光時間を安定させることができる
。そして遮光板は停止位置での揺動も起こさないので、遮光板は十分小型にしても入光と遮光の状態を安定して切り替えることができ、小型で精度の高い温度検出を行うことができる。また、連続して温度検出を行う場合や、短時間で繰り返して温度検出を行う場合は遮光板の位置合わせを行わずに続けて温度検出を行うことができるので、短時間で、精度の高い温度検出を行うことができ、また、長時間にわたり温度検出を行わず放置されている間に遮光板の位置がずれてしまった場合でも、再度温度検出を行う場合は遮光板の位置合わせを行った後温度検出を行うので、常に精度の高い温度検出を行うことができる。
【００３９】
（２）切替手段はモータ制御手段に電源が投入された時に位置合わせ駆動手段を動作させて遮光板の位置合わせを行い、そして、計時手段が発信手段からの温度検出開始信号が非受信状態である連続時間を計時し、所定の時間を計時する毎に定期的に切替手段が位置合わせ駆動手段を動作させて遮光板の位置合わせを行い、温度検出開始信号を受信した時に温度検出駆動手段を動作させて温度検出を行うので、短時間で繰り返して温度検出を行う場合は遮光板の位置合わせを行わずに続けて温度検出を行うことができるので、短時間で精度の高い温度検出を行うことができ、また、長時間にわたり温度検出を行わず放置されている間に遮光板の位置がずれてしまった場合でも、計時手段が所定の時間を計時する毎に定期的に遮光板の位置合わせを行うので、常に精度の高い温度検出を行うことができる。
【図面の簡単な説明】
【図１】本発明の実施例における温度検出装置の構成ブロック図
【図２】同実施例の遮光板部の要部拡大図
【図３】同実施例の動作を説明するタイミングチャート
【図４】本発明の第２の実施例の温度検出装置の構成ブロック図
【図５】同実施例のモータ制御手段の動作を説明するフローチャート
【図６】本発明の第３の実施例の温度検出装置の構成ブロック図
【図７】同実施例のモータ制御手段の動作を説明するフローチャート
【図８】同実施例の電源制御手段の動作を説明する回路図
【図９】本発明の第４の実施例の温度検出装置の構成ブロック図
【図１０】同実施例のモータ制御手段の動作を説明するフローチャート
【図１１】従来の温度測定装置の構成図
【図１２】第２の従来例の温度検出装置の構成図
【図１３】第２の従来例の動作を説明するタイミングチャート
【符号の説明】
１遮光板
２直流モータ
３赤外線検出器
１０被測定物
１３ストッパ
１４モータ制御手段
１５測定スイッチ（発信手段）
１５ａ温度検出開始信号
１６位置合わせ駆動手段
１７温度検出駆動手段
１８切替手段
２５計時手段
２８電源制御手段[0001]
BACKGROUND OF THE INVENTION
  The present invention relates to a temperature detection device that detects the temperature of an object in a non-contact manner, and more particularly to a light shielding plate that controls infrared light incident and light shielding.
[0002]
[Prior art]
  Conventionally, in the case of using a pyroelectric infrared detector as a temperature detection device that detects the temperature of an object in a non-contact manner, a light shielding plate that switches between incident light and light shielding of infrared light incident on the infrared detector is provided. ing. This light-shielding plate is made of a material that does not transmit infrared light, such as a metal plate, and its end is attached to a rotating shaft of a DC motor or AC motor and rotated to drive infrared light incident on the infrared detector. There is a method of repeatedly interrupting. That is, as shown in FIG. 11, the semicircular arc-shaped light-shielding plate 1 is attached to the rotating shaft of the direct current or alternating current motor 2 and is driven to rotate in the direction of the arrow, thereby interrupting the infrared light incident on the infrared detector 3.
[0003]
  There is also a method of intermittently irradiating infrared light by applying pulses at a predetermined cycle using a pulse motor as a rotation drive source and repeating forward rotation and reverse rotation at a predetermined angle, for example. For example, an example of a temperature measuring device disclosed in Japanese Patent Application Laid-Open No. 7-280652 will be described with reference to FIG. A chopper (light-shielding plate) 1 is driven to reciprocate by a quartz watch movement 4 which is a drive source based on the same principle as a pulse motor, and interrupts infrared light reaching the infrared detector 3. The quartz watch movement 4 includes a permanent magnet 5, a core 6 and a coil 7, and the end of the chopper 1 is attached to the permanent magnet 5. The coil 7 receives a pulse input at the first and second input terminals 8 and 9, the permanent magnet 5 rotates in response to the pulse input, and the chopper 1 reciprocates as indicated by arrows.
[0004]
[Problems to be solved by the invention]
  However, in the case of the above conventional example in which the light shielding plate is rotated using a DC motor as a drive source, there is a problem that the temperature measurement accuracy is low due to variations in the light incident time and the light shielding time. In general, the rotational speed of a DC motor fluctuates due to fluctuations in power supply voltage. If the rotation speed fluctuates, the period of incident light and light shielding changes, and the fluctuation of this period also fluctuates the output of the infrared detector, making accurate temperature detection impossible. In order to stabilize the number of revolutions, a complicated control circuit is required which provides a means for detecting the number of revolutions such as a photo interrupter and a means for adjusting the power supply voltage and performs feedback control.
[0005]
  When an AC motor is used as a drive source, the rotational speed is easier to stabilize than a DC motor under a relatively stable frequency like a commercial power source, but an AC power source such as a commercial power source is required. There is. This is difficult to achieve because it requires only a DC power source in the case of a battery power source such as a portable radiation thermometer or a radiation thermometer, and requires a complicated circuit for producing an AC power source with a stable frequency.
[0006]
  When a quartz watch movement or pulse motor is used as the drive source, it is driven based on a digital signal from a microprocessor, etc., so the light incident and light shielding cycles can be interrupted with high accuracy, but the light shielding plate stops while swinging. Therefore, there is a problem that it is difficult to switch between incident light and light shielding with high accuracy. In other words, these driving sources are stopped by the balance between the attractive force and the repulsive force due to the magnetic force, and are driven by changing the polarity of the magnetic force. Therefore, at the moment of stopping, the shading plate swings to balance the attractive force and the repulsive force. It has the characteristic of letting it stop.
[0007]
  FIG. 13 shows the characteristics of the behavior of the pulse motor. The abscissa is the elapsed time, and (a) is a drive pulse with CW (clockwise) and CCW (counterclockwise) pulses alternately output at a constant period t and a duty of 50%. When (b) reaches the stop position as shown in the figure at the rotation angle of the rotation shaft of the pulse motor, an overshoot occurs, and then an undershoot occurs, and the amplitude becomes stable while the amplitude decreases.
[0008]
  Since pulse motors and quartz watch movements generally have behavioral characteristics as shown in FIG. 13, if infrared light is intermittently used as a driving source of the light shielding plate, light is shielded from incident light, or light is incident from light shielding. At the moment of switching, there is a situation where the incident light and the light shielding are switched at a very short interval, which causes the problem that the output of the infrared detector becomes unstable and the accuracy of temperature detection is lacking. In order to avoid this problem, there is a method of making the shape of the light shielding plate sufficiently large with respect to Δθ which is the maximum position of oscillation, but in this case, there is a problem that the temperature detection device itself is also increased in size. .
[0009]
[Means for Solving the Problems]
  In order to solve the above-described problems, the present invention provides an infrared detector that detects infrared rays emitted from a measurement object, a light shielding plate that blocks infrared rays incident on the infrared detector, and a direct current motor that drives the light shielding plate. A stopper for determining the stop position of the light shielding plate, motor control means for controlling the DC motor, temperature conversion means for converting the temperature of the object to be measured based on the output of the infrared detector,A transmission means for transmitting a temperature detection start signal;The motor control means includes an alignment driving means for driving the direct current motor to align the light shielding plate, and an infrared ray that alternately reverses the rotation direction of the direct current motor and reaches the infrared detector. A temperature detection driving means for detecting temperature by switching light entering and blocking the light path; a switching means for switching between the alignment driving means and the temperature detection driving means;When the temperature detection start signal from the transmission means is in a non-receiving state Time measuring means for measuring the time, and when the time measuring means receives a temperature detection start signal from the transmitting means before measuring a predetermined time, the switching means operates the temperature detection driving means, and the time measuring means When the temperature detection start signal is received from the transmission means after measuring the time, the switching means operates the alignment drive means and then operates the temperature detection drive means.Is.
[0010]
  According to the above invention,When the time measuring means measures the continuous time in which the temperature detection start signal from the transmitting means is not received, and the time measuring means receives the temperature detection start signal before measuring the predetermined time, the switching means switches the temperature detection drive means. The temperature detection driving means reverses the rotation direction of the DC motor alternately, stops the light shielding plate by colliding with the stopper, switches between incoming light and light shielding of the infrared light path leading to the infrared detector, and the infrared detector is covered. The infrared rays emitted from the measurement object are detected, and the temperature conversion means converts the temperature of the measurement object based on the output of the infrared detector. When the time measuring means receives a signal from the transmitting means after measuring the predetermined time, the switching means operates the alignment driving means, and the alignment driving means drives the DC motor to cause the light shielding plate to collide with the stopper. After the alignment of the light shielding plate, the switching means operates the temperature detection driving means to detect the temperature. Therefore, by aligning the light shielding plate, the light shielding plate can always be at the same position when temperature detection is started, and the light incident time and light shielding time by driving the light shielding plate can be stabilized at the time of temperature detection. And since the light shielding plate does not swing at the stop position, even if the light shielding plate is sufficiently small, the light incident and light shielding states can be stably switched, and the temperature detection can be performed with a small size and high accuracy. . In addition, when temperature detection is repeatedly performed in a short time so as not to cause a positional deviation from the final stop position of the light shielding plate at the time of temperature detection, the temperature detection is continued without performing alignment of the light shielding plate. Therefore, it is possible to detect the temperature with high accuracy in a short time, and even if the position of the light shielding plate is shifted while being left without performing temperature detection for a long time, When performing temperature detection again, temperature detection is performed after the position of the light-shielding plate is adjusted, so that highly accurate temperature detection can always be performed.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
  According to a first aspect of the present invention, there is provided a temperature detection apparatus comprising: an infrared detector that detects infrared rays emitted from an object to be measured; a light shielding plate that blocks infrared rays incident on the infrared detector; and a direct current that drives the light shielding plate. A motor, a stopper for determining the stop position of the light shielding plate, motor control means for controlling the DC motor, temperature conversion means for converting the temperature of the object to be measured based on the output of the infrared detector,A transmission means for transmitting a temperature detection start signal;The motor control means includes
Position detection drive means for driving the flow motor to align the light shielding plate, and temperature detection by switching light incident and light shielding on the infrared light path to the infrared detector by alternately reversing the rotation direction of the DC motor Temperature detection drive means for performing, switching means for switching the alignment drive means and the temperature detection drive means,Switching when the temperature detection start signal from the transmission means is received before the time measurement means counts a predetermined time, having a time measurement means for measuring a continuous time in which the temperature detection start signal from the transmission means is not received. The means operates the temperature detection driving means, and when the timing means receives a temperature detection start signal from the transmitting means after measuring a predetermined time, the switching means operates the alignment driving means and then operates the temperature detection driving means. LetIs.
[0012]
  Then, when the time measuring means measures the continuous time in which the temperature detection start signal from the transmitting means is not received, and the time measuring means receives the temperature detection start signal before measuring the predetermined time, the switching means drives the temperature detection. The temperature detection drive means alternately reverses the direction of rotation of the DC motor, causes the light-shielding plate to collide with the stopper and stops, and switches between entering and shielding the infrared light path leading to the infrared detector. Detects the infrared rays emitted from the object to be measured, and the temperature conversion means converts the temperature of the object to be measured based on the output of the infrared detector. When the time measuring means receives a signal from the transmitting means after measuring the predetermined time, the switching means operates the alignment driving means, and the alignment driving means drives the DC motor to cause the light shielding plate to collide with the stopper. After the alignment of the light shielding plate, the switching means operates the temperature detection driving means to detect the temperature. Therefore, the light shielding plate can always be in the same position at the start of temperature detection by positioning the light shielding plate. It is possible to stabilize the light incident time and the light shielding time by driving the light shielding plate during the degree detection. And since the light shielding plate does not swing at the stop position, even if the light shielding plate is sufficiently small, the light incident and light shielding states can be stably switched, and the temperature detection can be performed with a small size and high accuracy. . In addition, when temperature detection is repeatedly performed in a short time so as not to cause a positional deviation from the final stop position of the light shielding plate at the time of temperature detection, the temperature detection is continued without performing alignment of the light shielding plate. Therefore, it is possible to detect the temperature with high accuracy in a short time, and even if the position of the light shielding plate is shifted while being left without performing temperature detection for a long time, When performing temperature detection again, temperature detection is performed after the position of the light-shielding plate is adjusted, so that highly accurate temperature detection can always be performed.
[0013]
  Further, the claims of the present invention2The temperature detection device related toAn infrared detector for detecting infrared rays emitted from the object to be measured; a light shielding plate for shielding infrared rays incident on the infrared detector; a DC motor for driving the light shielding plate; and a stopper for determining a stop position of the light shielding plate. Motor control means for controlling the DC motor; temperature conversion means for converting the temperature of the object to be measured based on the output of the infrared detector; and transmission means for transmitting a temperature detection start signal. The control means drives the direct current motor to align the light shielding plate, and the light incident on the light path of the infrared light that reaches the infrared detector by alternately reversing the rotation direction of the direct current motor. A temperature detection driving means for detecting temperature by switching, a switching means for switching between the alignment driving means and the temperature detection driving means, andHaving time measuring means for measuring the continuous time in which the temperature detection start signal from the transmitting means is in a non-reception state;SaidThe switching means detects the temperature when the motor control means is turned on, and whenever the time measuring means counts a predetermined time, the alignment driving means is operated and a temperature detection start signal is received from the transmitting means. Operate drive meansBy doing so, the temperature detecting device is characterized in that the light shielding plate is always in the same position at the start of temperature detection.
[0014]
  The switching means operates the alignment driving means when the power is turned on to the motor control means to align the light shielding plate, and the timing means is in a state of not receiving the temperature detection start signal from the transmitting means. Whenever the continuous time is counted, the switching means operates the alignment driving means periodically to align the light shielding plate every time the predetermined time is measured, and the temperature detection driving means is operated when the temperature detection start signal is received. Therefore, if temperature detection is performed repeatedly in a short time, the temperature detection can be continued without positioning the light shielding plate.
The temperature can be detected with high accuracy over time, and even if the position of the light-shielding plate shifts while it is left undetected for a long time, the time measuring means measures the predetermined time. Since the position of the light shielding plate is periodically adjusted every time, highly accurate temperature detection can always be performed.
[0015]
【Example】
  (Example 1)
  Embodiments of the present invention will be described below with reference to FIGS. FIG. 1 is a configuration block diagram of an application example in which a temperature detection device is mounted on a thermometer as an embodiment of the present invention. 2 is an enlarged view of a main part of the light shielding plate, and FIG. 3 is a timing chart showing a control method of the DC motor.
[0016]
  In general, as a thermometer for measuring the surface temperature, it is possible to measure the body temperature almost by measuring the temperature of a part of the eardrum, oral cavity, anus and the like that is difficult to contact with outside air. In particular, the eardrum is close to the hypothalamus, which controls body temperature, and is known as an appropriate place for body temperature measurement. In FIG. 1, reference numeral 10 denotes an object to be measured for temperature, for example, an eardrum. 11 is a professional to insert into the ear canal
The diameter of the probe decreases toward the tip, making it easy to insert into the ear canal. Reference numeral 12 denotes a lens that collects infrared rays emitted from the eardrum 10, and 3 denotes a pyroelectric infrared detector that detects infrared rays collected by the lens 12, and has a correlation with a differential value of the amount of infrared rays to be detected. The output changes. Further, 1 is a light shielding plate for shielding infrared rays incident on the infrared detector 3, 2 is a direct current motor for driving the light shielding plate 1, 13 is a stopper provided at a stop position of the light shielding plate 1 and stopping the light shielding plate 1, and 14 is a direct current A motor control means 15 for controlling the motor 2 and a transmission switch 15 for transmitting a temperature detection start signal 15a to the motor control means 14 are measurement switches. The motor control means 14 is an alignment driving means 16 for driving the DC motor 2 to align the light shielding plate 1, a temperature detection driving means 17 for alternately reversing the rotation direction of the DC motor 2 at the time of temperature detection, and an alignment driving. A switching means 18 for switching the means 16 and the temperature detection driving means 17 is provided. Reference numeral 19 denotes a temperature sensor for detecting the temperature of the infrared detector 3 itself, which is a thermistor. 20 is an amplifier that amplifies the voltage output from the infrared detector 3, 21 is an AD converter that converts the output of the amplifier 20 and the output of the temperature sensor 19 from an analog value to a digital value, and 22 is an output of the AD converter 21. Based on the temperature conversion means 23 for converting to temperature, 23 is a display means for displaying the temperature calculated by the temperature conversion means 22.
[0017]
  In the above configuration, when the body temperature is measured, the probe 11 is inserted into the ear hole and the measurement switch 15 that transmits the temperature detection start signal 15a is pressed. When the motor control means 14 receives the temperature detection start signal 15a, the switching means 18 first operates the alignment driving means 16, and the alignment driving means 16 drives the DC motor 2 to align the light shielding plate 1. Thereafter, the switching unit 18 switches to the temperature detection driving unit 17, and the temperature detection driving unit 17 alternately reverses the rotation direction of the DC motor 2. By the rotation of the direct current motor 2, the light shielding plate 1 repeats reciprocating rotation between the stoppers 13 provided at the stop position, interrupts the infrared light path from the eardrum 10 to the infrared detector 3, and switches between incident light and light shielding. Here, the light shielding plate 1 is made of metal, and when the light is shielded, the infrared light emitted from the infrared detector 3 itself is reflected by the metal surface and enters the infrared detector 3. By the intermittent operation, the infrared ray emitted from the eardrum 10 and the infrared ray emitted from the infrared detector 3 itself are alternately detected by the infrared detector 3. The infrared detector 3 is a pyroelectric type, and its output changes with a correlation with the differential value of the sensed infrared amount. Therefore, the output of the infrared detector 3 has a correlation with the temperature difference between the eardrum 10 and the infrared detector 3. Yes. Therefore, the temperature conversion means 22 converts the temperature of the eardrum 10 using this relationship. That is, the output of the infrared detector 3 is amplified by the amplifier 20, the output voltage amplified by the amplifier 20 and the output voltage of the temperature sensor 19 are digitized by the AD converter 21, and the temperature conversion means is based on the output of the AD converter 21. 22 converts the temperature of the eardrum 10. Then, the temperature is displayed on the display means 23.
[0018]
  Next, the alignment driving and temperature detection driving of the light shielding plate 1 will be described in detail with reference to FIGS. In the enlarged view of the light shielding plate portion of FIG. 2, the stopper 13 is in contact with the light shielding stop portion 13 a that contacts when the light shielding plate 1 stops in the light shielding state where the infrared detector 3 shields the light. The light blocking unit 13b includes the light stopping unit 13b, and the light shielding plate 1 attached to the shaft 24 is moved between the light blocking stopping unit 13a and the light incident stopping unit 13b by the rotation of the DC motor 2. In the figure, the state where the light shielding plate 1 is stopped in the light shielding state is indicated by a solid line, and the state where the light shielding plate 1 is stopped in the light incident state is indicated by a broken line.
[0019]
  In the above configuration, when the measurement switch 15 is pressed and the motor control unit 14 receives the temperature detection start signal 15a, the switching unit 18 first operates the alignment driving unit 16 to align the light shielding plate 1. That is, as shown in FIG. 3, the alignment driving means 16 supplies power to the DC motor 2 for t1 time from the reception of the temperature detection start signal 15a, and rotates the light shielding plate 1 in the light shielding direction shown in FIG. Here, t1 is a time longer than the time required for the light shielding plate to move from the state where it is stopped in the infrared light incident state (broken line) to the state where it is stopped in the light shielding state (solid line). Thereby, before the motor control means 14 receives the temperature detection start signal 15a, no matter what position the light shielding plate 1 stops between the light shielding stop portion 13a and the light incident stop portion 13b, the light shielding plate 1 is moved. It can collide with the light shielding stop part 13a and can always be stopped in a light shielding state, and the light shielding plate 1 can be aligned.
[0020]
  After the alignment of the light shielding plate 1, the switching means 18 switches to the temperature detection driving means 17, and the temperature detection driving means 17 supplies power to the DC motor 2 as shown in FIG. 3 for temperature detection. Then, the light shielding plate 1 is driven. That is, first, power is supplied for the time t1 to rotate the light-shielding plate 1 in the light incident direction to stop the collision to the light incident stop portion 13b, and then the power is intermittently supplied for the subsequent time t2 to stop the position, that is, the light incident. The light shielding plate 1 is held in a state. Further, power is supplied in the opposite direction for the next t1 time to rotate the light-shielding plate 1 in the light-shielding direction to stop the collision with the light-shielding stop portion 13a, and power is intermittently supplied for the time t2, and the stop position, The light shielding plate 1 is held in a light shielding state. In this way, the temperature detection drive means 17 repeats the incident and shielding of infrared rays reaching the infrared detector 3 by the light shielding plate 1 by alternately inverting the DC motor 2, and finally ends in the light shielding state. And
[0021]
  Here, the output of the infrared detector 3 in which the temperature detection driving means 17 is operating becomes an AC waveform as shown in FIG. 3 by the intermittent operation of infrared rays by the light shielding plate 1, and the amplitude V of this AC waveform is the temperature of the eardrum 10. Is proportional to the difference of the fourth power of the temperature of the infrared detector 3. Therefore, based on this relationship, the temperature conversion means 22 is obtained by calculating back the temperature of the eardrum 10 from the amplitude V and the temperature of the infrared detector 3 detected by the temperature sensor 19, and further repeating the light incident and light shielding. A plurality of temperatures are averaged to obtain the temperature of the eardrum 10. Thus, by repeating the incident light and the light shielding and averaging a plurality of data, the influence of noise and the like can be reduced, and the temperature measurement accuracy can be improved. In addition, although the light-shielding plate 1 was driven and light-incidence and light-shielding were repeated several times, temperature may be converted only by light-incidence and light-shielding once, and in that case, temperature detection time can be shortened.
[0022]
  As described above, according to the present embodiment, the switching means 18 switches between the alignment driving means 16 and the temperature detection driving means 17, and after the alignment driving means 16 aligns the light shielding plate 1, the temperature detection driving means 17 is DC. Since the temperature detection is performed by alternately reversing the direction of rotation of the motor 2 and switching between infrared light incoming and light shielding by the light shielding plate 1, the light shielding plate 1 can always be at the same position when temperature detection is started. The light incident time and the light shielding time by driving the light shielding plate 1 can be stabilized, and highly accurate temperature detection can be performed.
[0023]
  Then, the light shielding plate 1 driven by the DC motor 2 is caused to collide with a stopper 13 provided at the stop position, so that the light shielding plate 1 can be stopped in each of the infrared light incident state and the light shielding state.
Since the light shielding plate does not swing at the stop position, even if the light shielding plate 1 is sufficiently small, it is possible to stably switch between the light incident state and the light shielding state, and the small and highly accurate temperature detection is possible. It can be carried out.
[0024]
  Further, by terminating the driving of the light shielding plate 1 for temperature detection at the stop position where the infrared light is shielded, it is possible to prevent the infrared detector 3 from being contaminated with dust or dirt at the time of non-temperature detection. Can keep.
[0025]
  Further, in the present embodiment, the alignment driving means 18 drives the light shielding plate 1 to a position where the infrared rays reaching the infrared detector 3 are shielded, and this is performed by the temperature detection driving means 19. There is an effect of making the number of times of driving the light shielding plate 1 most efficient. That is, the greater the output amplitude V of the infrared detector 3 at the time of temperature detection, the less affected by the noise and the better the temperature accuracy, so light incident and light shielding or a combination of light shielding and light incident can be achieved. It is considered that it is preferable to obtain the output amplitude V, and temperature detection is performed by light incident and light shielding, or a combination of light shielding and light incident. Here, if the alignment driving means 18 drives the light shielding plate 1 in the light incident state and performs alignment, the temperature detection driving means 19 starts temperature detection from the point where the light shielding plate 1 is driven to the light shielding state. In order to prevent the infrared detector 3 from being contaminated with dust or the like during non-temperature detection, it is necessary to further drive the light shielding plate 1 to the light shielding state. Compared with the case where the alignment driving means 18 drives the light shielding plate 1 in the light shielding state to perform alignment, the number of times of driving the light shielding plate 1 is increased by one. Therefore, the alignment driving means 18 can drive the light shielding plate 1 most efficiently by performing alignment by driving the light shielding plate 1 in a light shielding state.
(Example 2)
  Hereinafter, a second embodiment of the present invention will be described with reference to FIGS. FIG. 4 is a block diagram showing the configuration of a thermometer equipped with a temperature detecting device according to the second embodiment of the present invention, and FIG. 5 is a flowchart for explaining the operation of the motor control means of the same embodiment.
[0026]
  In FIG. 4, 25 is a time measuring means for measuring a continuous time in which the temperature detection start signal 15a from the measurement switch 15 is not received, and 26 is a memory for storing a time lapse flag when the time measuring means 25 measures a predetermined time. Means 27 is a determination means for determining the presence or absence of a time lapse flag stored in the storage means 26 and instructing the subsequent operation of the switching means 18. Components similar to those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted.
[0027]
  Next, the operation of the motor control means 14 will be specifically described with reference to FIG. First, when the motor control unit 14 is powered on, a time lapse flag is stored in the storage unit 26 as an initial state (S100), and the following operations are repeated. That is, if the time measured by the time measuring means 25 in S101 has not passed the predetermined time t3, the storage means 26 is left as it is and waits for the reception of the temperature detection start signal 15a. When the predetermined time t3 elapses, a time elapse flag is stored in the storage means 26 in S102, and the system waits for reception of the temperature detection start signal 15a. Eventually, when the measurement switch 15 is pressed and the motor control unit 14 receives the temperature detection start signal 15a (S103), the determination unit 27 checks whether or not the time lapse flag is stored in the storage unit 26 (S104). . Here, when the time lapse flag is not stored, the switching unit 18 immediately activates the temperature detection driving unit 17 (S106). If the time lapse flag is stored, the switching unit 18 operates the alignment driving unit 16 (S105), and then switches to the temperature detection driving unit 17 to operate (S106). Thereafter, the time measuring means 25 is driven to reset (S107), the time lapse flag stored in the storage means 26 is erased (S108), the process returns to the beginning, and the same is repeated.
[0028]
  With the above configuration, temperature detection is performed for the first time after the motor control unit 14 is powered on.
In this case, since the time elapse flag is stored in the storage means 26, the temperature is detected after the alignment of the light shielding plate 1, so that the position of the light shielding plate is determined while the power is turned off. Even in the case of deviation, temperature detection with high accuracy can be performed. In the temperature detection after the first time after the power is turned on, when the temperature detection is continuously performed or when the temperature detection is repeatedly performed in a short time without the predetermined time t3, the alignment of the light shielding plate 1 is performed. Temperature detection can be performed continuously without performing the above, so that accurate temperature detection can be performed in a short time, and the temperature detection is not performed for a long time after a predetermined time t3. Even if the position of the light-shielding plate 1 is shifted, the temperature detection is performed after the alignment of the light-shielding plate 1 when the temperature detection is performed again, so that highly accurate temperature detection can always be performed.
[0029]
  (Example 3)
  Hereinafter, a third embodiment of the present invention will be described with reference to FIGS. FIG. 6 is a block diagram showing the configuration of a thermometer equipped with a temperature detector according to a third embodiment of the present invention, FIG. 7 is a flowchart for explaining the operation of the motor control means of the embodiment, and FIG. It is a circuit diagram explaining operation | movement of a power supply control means. In FIG. 6, 28 is a power supply control means for controlling the turning on and off of the motor control means 14 for controlling the DC motor 2, and measures the continuous time when the temperature detection start signal 15a from the measurement switch 15 is not received. It has time measuring means 25 for In addition, the same code | symbol is attached | subjected to the component similar to the above-mentioned Example, and description is abbreviate | omitted.
[0030]
  Next, the operation of the motor control means 14 will be specifically described with reference to FIG. First, when the power of the motor control means 14 is turned on by the power control means 28, the switching means 18 operates the alignment driving means 16 to align the light shielding plate 1 (S200), and at the same time, the time measurement means 25 measures the time. Is started (S201). The motor control means 14 waits for the reception of the temperature detection start signal 15a until the time measurement means 25 counts the predetermined time t3 (S202), and the temperature measurement start signal 15a is pressed by pressing the measurement switch 15 during standby. Is received (S203), the switching means 18 operates the temperature detection driving means 17 to start temperature detection (S204). Thereafter, the time measuring means 25 is set to start the time measurement again, and the same is repeated. When the time measuring means 25 measures the predetermined time t3 while the motor control means 14 waits for the temperature detection start signal 15a to be received, the power supply control means 28 shuts off the power supply of the motor control means 14 (S205). When it is desired to detect the temperature after the power source of the motor control unit 14 is cut off, the power is turned on again after the motor control unit 14 is turned on.
[0031]
  Next, the power supply control means 28 will be described with reference to FIG. The power control means 28 includes a microcomputer 29 (hereinafter referred to as a microcomputer), a battery 30 which is a DC power supply, a PNP transistor 31, resistors 32, 33 and 34, diodes 35 and 36, and a power switch 37. It is composed. In FIG. 8, when the power switch 37 is pressed, current flows through the resistors 32 and 33, the diode 35, and the power switch 37, the transistor 31 is turned on, and power is supplied to the microcomputer 29 and the motor control means 14. Here, the microcomputer 29 can keep the transistor 31 in the on state even when the power switch 37 is released by setting the output terminal 29 a to low, and can continue to supply power to the microcomputer 29 and the motor control means 14. On the other hand, when the power switch 37 is pressed, current flows from the transistor 31 to the resistor 34 and the diode 36, and the input terminal 29b of the microcomputer 29 can input low, and when it is released, high can be input.
[0032]
  In general usage, when the power switch 37 is pressed, the microcomputer 29 keeps the output terminal 29a low and continues to supply power to the microcomputer 29 and the motor control means 14. Here, when the measurement switch 15 that transmits the temperature detection start signal 15a is pressed, current flows from the resistor 38 to the measurement switch 15, and the microcomputer 29 has pressed the measurement switch 15 because the input terminal 29c goes low. Is detected and temperature is measured. When the power switch 37 is pressed again, the microcomputer 29 sets the output terminal 29a to high, so that the microcomputer 29 instantly releases the power switch 37.
The power supply of the icon 29 and the motor control means 14 can be stopped.
[0033]
  If the user forgets to press the power switch 37 again and power is continuously supplied to the microcomputer 29 and the motor control means 14, the microcomputer 29 sets the output terminal 29a to high in order to avoid unnecessary battery consumption. Power supply can be stopped. It is only necessary to count the continuous time in which the microcomputer 29 has the time measuring means 25 and the measurement switch 15 is not pressed, and when the time exceeds the predetermined time, the output terminal 29a is made high.
[0034]
  Therefore, according to the present embodiment, since the alignment of the light shielding plate 1 is performed when the motor control unit 14 is turned on, temperature detection can be performed in a short time. When the temperature detection is repeatedly performed, the temperature detection can be continuously performed without performing the alignment of the light shielding plate 1 until the time measuring means 25 measures the predetermined time. Even when the temperature can be detected and the temperature is not detected for a long time and the light-shielding plate 1 is misaligned, the time measuring means 25 keeps a predetermined time, and the motor control means 14 is powered on. Therefore, when the temperature is detected again, the motor control means 14 is turned on so that the switching means 18 operates the alignment driving means 16 to align the light shielding plate 1, and the temperature detection thereafter. Since temperature detection is performed with the start signal 15a, highly accurate temperature detection can always be performed. Further, even if the power of the motor control unit 14 is forgotten to be turned off, the power is automatically shut off when a predetermined time elapses, so that the power consumption can be reduced and the usability is improved.
[0035]
  (Example 4)
  The fourth embodiment of the present invention will be described below with reference to FIGS. FIG. 9 is a block diagram showing the configuration of a thermometer equipped with a temperature detecting device according to a fourth embodiment of the present invention, and FIG. 10 is a flowchart for explaining the operation of the motor control means of the same embodiment. The operation of the motor control means 14 will be specifically described with reference to FIGS. First, when the power of the motor control unit 14 is turned on, the switching unit 18 operates the alignment driving unit 16 to perform alignment of the light shielding plate 1 (S300), and timing by the timing unit 25 is started (S301). ). The motor control means 14 waits for reception of the temperature detection start signal 15a until the time measurement means 25 measures the predetermined time t3 (S302), and the measurement switch 15 is pressed to receive the temperature detection start signal 15a. Then (S303), the switching means 18 activates the temperature detection driving means 17 and starts temperature detection (S304). After the temperature detection is started, the time measuring means 25 is reset (S305), and the motor control means 14 again enters a standby state waiting for the reception of the temperature detection start signal 15a, and the same is repeated. During the standby, every time the time measuring means 25 measures the predetermined time t3, the switching means 18 operates the alignment driving means 16 to align the light shielding plate 1.
[0036]
  Therefore, according to the present embodiment, the time measuring means 25 measures the continuous time in which the temperature detection start signal 15a from the measurement switch 15 is not received, and the switching means 18 is periodically positioned every time a predetermined time is measured. The alignment driving means 16 is operated to align the light shielding plate 1, and when the temperature detection start signal 15a is received, the temperature detection driving means 17 is operated to detect the temperature. Since temperature detection can be continuously performed without aligning the light-shielding plate 1, highly accurate temperature detection can be performed in a short time, and while the temperature detection is not performed for a long time, Even if the position of the light shielding plate 1 is shifted, the position of the light shielding plate 1 is periodically adjusted every time the time measuring means 25 measures a predetermined time, so that highly accurate temperature detection can always be performed. The
[0037]
【The invention's effect】
  As described above, the temperature detector of the present invention has the following effects.
[0038]
    (1) By aligning the light shielding plate, the light shielding plate can always be at the same position when temperature detection is started, and the light incident time and light shielding time by driving the light shielding plate can be stabilized at the time of temperature detection.
. And since the light shielding plate does not swing at the stop position, even if the light shielding plate is sufficiently small, the light incident and light shielding states can be stably switched, and the temperature detection can be performed with a small size and high accuracy. . In addition, when performing temperature detection continuously, or when performing temperature detection repeatedly in a short time, temperature detection can be performed continuously without performing alignment of the light shielding plate. Temperature detection can be performed, and even if the position of the light shielding plate is shifted while left undetected for a long time, if the temperature is detected again, the light shielding plate must be aligned. After that, since temperature detection is performed, highly accurate temperature detection can always be performed.
[0039]
  (2) The switching means operates the alignment driving means when the motor control means is turned on to align the light shielding plate, andThe time measuring means measures the continuous time when the temperature detection start signal from the transmitting means is not received, and the switching means operates the alignment driving means periodically every time a predetermined time is measured to align the light shielding plate. When the temperature detection start signal is received, the temperature detection drive unit is operated to detect the temperature.If the temperature detection is repeated in a short time, the temperature detection is continued without performing the alignment of the light shielding plate. Therefore, it is possible to detect temperature with high accuracy in a short time, and even if the position of the light-shielding plate shifts while left undetected for a long time, Since the position of the light shielding plate is periodically adjusted every time a predetermined time is counted, temperature detection with high accuracy can always be performed.
[Brief description of the drawings]
FIG. 1 is a block diagram illustrating a configuration of a temperature detection device according to an embodiment of the present invention.
FIG. 2 is an enlarged view of the main part of the light shielding plate part of the embodiment.
FIG. 3 is a timing chart for explaining the operation of the embodiment.
FIG. 4 is a block diagram showing the configuration of a temperature detection apparatus according to a second embodiment of the present invention.
FIG. 5 is a flowchart for explaining the operation of the motor control means of the embodiment.
FIG. 6 is a block diagram showing the configuration of a temperature detection apparatus according to a third embodiment of the present invention.
FIG. 7 is a flowchart for explaining the operation of the motor control means of the embodiment.
FIG. 8 is a circuit diagram for explaining the operation of the power supply control means of the embodiment.
FIG. 9 is a block diagram showing the configuration of a temperature detection apparatus according to a fourth embodiment of the present invention.
FIG. 10 is a flowchart for explaining the operation of the motor control means of the embodiment.
FIG. 11 is a configuration diagram of a conventional temperature measuring device.
FIG. 12 is a configuration diagram of a temperature detection device of a second conventional example.
FIG. 13 is a timing chart for explaining the operation of the second conventional example.
[Explanation of symbols]
1 Shading plate
2 DC motor
3 Infrared detector
10 DUT
13 Stopper
14 Motor control means
15 Measurement switch (transmission means)
15a Temperature detection start signal
16 Positioning drive means
17 Temperature detection drive means
18 Switching means
25 Timekeeping means
28 Power control means

Claims

An infrared detector for detecting infrared rays emitted from the object to be measured; a light shielding plate for shielding infrared rays incident on the infrared detector; a DC motor for driving the light shielding plate; and a stopper for determining a stop position of the light shielding plate. Motor control means for controlling the DC motor; temperature conversion means for converting the temperature of the object to be measured based on the output of the infrared detector; and transmission means for transmitting a temperature detection start signal. The control means drives the direct current motor to align the light shielding plate, and the light incident on the light path of the infrared light that reaches the infrared detector by alternately reversing the rotation direction of the direct current motor. a temperature detecting driver means for performing temperature detection by switching, and switching means for switching the temperature detecting driver means and said alignment drive means, the temperature detection starting signal from said transmitting means is a non-receiving A time measuring means for measuring a continuous time in a state, and when the time measuring means receives a temperature detection start signal from the transmitting means before measuring a predetermined time, the switching means operates the temperature detection driving means, and the time measuring When the means receives the temperature detection start signal from the transmitting means after measuring a predetermined time, the light shielding plate is operated at the start of temperature detection by operating the temperature detection drive means after the switching means operates the alignment drive means. A temperature detector characterized by being always in the same position.

An infrared detector for detecting infrared rays emitted from the object to be measured; a light shielding plate for shielding infrared rays incident on the infrared detector; a DC motor for driving the light shielding plate; and a stopper for determining a stop position of the light shielding plate. Motor control means for controlling the DC motor; temperature conversion means for converting the temperature of the object to be measured based on the output of the infrared detector; and transmission means for transmitting a temperature detection start signal. The control means drives the direct current motor to align the light shielding plate, and the light incident on the light path of the infrared light that reaches the infrared detector by alternately reversing the rotation direction of the direct current motor. a temperature detecting driver means for performing temperature detection by switching, and switching means for switching the temperature detecting driver means and said alignment drive means, the temperature detection starting signal from said transmitting means is a non-receiving Has a counting means for counting the a is continuous-time state, said switching means and when the power is turned on the motor control means, said time measuring means operates the positioning drive means for each counting a predetermined time, The temperature detecting device according to claim 1, wherein when the temperature detection start signal is received from the transmitting means, the temperature detection driving means is operated so that the light shielding plate is always in the same position when the temperature detection is started .