JP2719038B2 - Bioacoustic transducer - Google Patents
Bioacoustic transducerInfo
- Publication number
- JP2719038B2 JP2719038B2 JP2245752A JP24575290A JP2719038B2 JP 2719038 B2 JP2719038 B2 JP 2719038B2 JP 2245752 A JP2245752 A JP 2245752A JP 24575290 A JP24575290 A JP 24575290A JP 2719038 B2 JP2719038 B2 JP 2719038B2
- Authority
- JP
- Japan
- Prior art keywords
- vibration
- piezoelectric film
- diaphragm
- bioacoustic
- polymer piezoelectric
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
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- Measuring Pulse, Heart Rate, Blood Pressure Or Blood Flow (AREA)
Description
【発明の詳細な説明】 ［産業上の利用分野］ 本発明は、動脈瘤をはじめとする血管障害、特に脳血
管障害部位より発生する可聴周波数領域の音響振動を、
体表面、特にまぶたの表面において検出する生体音響変
換器に関する。DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to vascular disorders such as aneurysms, in particular, acoustic vibration in an audible frequency region generated from a cerebrovascular disorder site.
The present invention relates to a bioacoustic transducer for detecting on a body surface, particularly on an eyelid surface.
［従来の技術］ 脳動脈瘤や脳動静脈奇形が原因で起こる脳出血は、く
も膜下出血として知られ、突然に発生するとともに死に
至る場合が多いため、恐れられている病気の一つになっ
ている。しかし、この動脈瘤の存在の有無を簡単に予知
する有力な方法は得られておらず、現在は唯一、血管造
影法にによらざるを得ない状態である。血管造影法は、
最も脳動脈瘤の検出確度が高く、現在最も一般的な検査
方法であり、比較的小さな脳動脈瘤の検出が可能であ
る。しかしながら、この検査方法では、患者の体内にカ
テーテルを入れ、造影剤を注入しなければならず、その
ため患者には相当な苦痛を与えることになり、さらにこ
の検査を受けるためには数日の入院が必要であるなどの
欠点がある。[Prior art] Cerebral hemorrhage caused by cerebral aneurysm or cerebral arteriovenous malformation is known as subarachnoid hemorrhage, and it is one of the feared diseases because it occurs suddenly and often leads to death. I have. However, a powerful method for easily predicting the presence or absence of the aneurysm has not been obtained, and at present, the only way is to rely on angiography. Angiography is
It has the highest detection accuracy for cerebral aneurysms and is currently the most common test method, and is capable of detecting relatively small cerebral aneurysms. However, this method requires a catheter to be inserted into the patient's body and the injection of a contrast agent, which can cause considerable pain for the patient, and may require several days of hospitalization to undergo the test. Is necessary.
くも膜下出血の原因の多くは脳動脈瘤の破裂である。
動脈瘤、動静脈奇形、動脈挟窄などの血管異常がある
と、その血管異常箇所からは可聴周波数領域の血流雑音
が発生していることが知られており、近年、その血流雑
音を頭蓋外体表面より非侵襲的に検出する方法が試みら
れている。（C.P.Olinger and J.F.Wasserman,"Electro
nic stethoscope for detection of cerebral aneurys
m,vassospasm and arterial diseases",Surgical Neuro
logy 8,298−312（1977）、及び日本音響学会誌38巻10
号,1982,P657〜662を参照）。Many of the causes of subarachnoid hemorrhage are ruptures of cerebral aneurysms.
It is known that if there is a blood vessel abnormality such as an aneurysm, arteriovenous malformation, or arterial stenosis, blood flow noise in the audible frequency region is generated from the blood vessel abnormality site. Methods for non-invasive detection from the surface of the extracranial body have been attempted. (CPOlinger and JFWasserman, "Electro
nic stethoscope for detection of cerebral aneurys
m, vassospasm and arterial diseases ", Surgical Neuro
logy 8,298-312 (1977), and The Acoustical Society of Japan, 38, 10
No. 1982, pp. 657-662).
［発明が解決しようとする課題］ しかしながら、上記の方法は、空気伝導形の聴診マイ
クを眼球上に当て、眼窩の背後に位置する動脈瘤から視
束孔を通してリークしてくる音を分析し、動脈瘤を検出
するものである。この場合、血管障害部位で発生する血
流雑音は極く微弱であるが、この微弱な血流雑音を脳内
と音響的につながっている眼窩を利用し、眼球上で検出
するというものであり有効な方法であるが、この方法は
空気伝導形であって、空気層が介在するため検出感度が
低く、また、周囲の雑音を拾い易いという問題があっ
た。[Problems to be Solved by the Invention] However, the above-mentioned method puts an air-conducting auscultation microphone on the eyeball, analyzes the sound leaking from the aneurysm located behind the orbit through the optic foramen, This is to detect an aneurysm. In this case, the blood flow noise generated at the site of vascular injury is extremely weak, but this weak blood flow noise is detected on the eyeball using the orbit that is acoustically connected to the brain. Although this method is effective, this method is of an air conduction type, and has a problem that detection sensitivity is low due to the presence of an air layer, and that ambient noise is easily picked up.
本発明者は、このような技術の問題を解決するため種
々研究を重ねた結果、まぶたの外表面へ伝わってくる血
流雑音の音響振動を、振動板の振動変位として捕えるこ
とができることに着目し、本発明に到達したものであ
る。The present inventor has conducted various researches to solve such a problem of the technique, and as a result, has noticed that the acoustic vibration of blood flow noise transmitted to the outer surface of the eyelid can be captured as a vibration displacement of the diaphragm. Thus, the present invention has been achieved.
［課題を解決するための手段］ 即ち、本発明によれば、一端部は閉ざされ、他端部は
開口された箱体の開口部に、厚さ0.05〜0.5mmの弾性材
料よりなる振動板を取付けるとともに、延伸方向が長手
方向である帯状の高分子圧電フィルムの両端を該箱体の
開口部に取付け、かつ前記振動板の中央部と該高分子圧
電フィルムの中央部とを小片からなる結合子にて結合す
ることにより、音響振動を、前記振動板の振動、前記結
合子の上下振動、及び前記高分子圧電フィルムの伸縮振
動を介して捕らえ、この伸縮振動を前記高分子圧電フィ
ルムの圧電性により電気信号として取り出すことを特徴
とする生体音響変換器が提供される。[Means for Solving the Problems] That is, according to the present invention, a diaphragm made of an elastic material having a thickness of 0.05 to 0.5 mm is provided at an opening of a box body having one end closed and the other end opened. At the same time, both ends of the strip-shaped polymer piezoelectric film whose stretching direction is the longitudinal direction are attached to the opening of the box, and the center of the diaphragm and the center of the polymer piezoelectric film are formed of small pieces. By coupling with the connector, the acoustic vibration is captured via the vibration of the diaphragm, the vertical vibration of the connector, and the expansion and contraction vibration of the polymer piezoelectric film, and the expansion and contraction vibration of the polymer piezoelectric film is captured. There is provided a bioacoustic transducer characterized by taking out as an electric signal by piezoelectricity.
また、本発明においては、振動板と高分子圧電フィル
ムとで形成される角度を５°〜30°とすることが望まし
い。In the present invention, it is desirable that the angle formed between the diaphragm and the polymer piezoelectric film is 5 ° to 30 °.
［作用］ 本発明の生体音響変換器においては、頭蓋内異常部で
発生する血流に伴う音響振動を視神経を通してまぶたの
外表面で捕え、この音響振動を振動板の振動、結合子の
上下振動、及び高分子圧電フィルムの伸縮振動を介して
捕え、この伸縮振動をフィルムの圧電性により電気信号
として取り出し、脳血管障害の有無を判定する。[Action] In the bioacoustic transducer of the present invention, acoustic vibrations caused by blood flow generated in an abnormal intracranial region are captured by the outer surface of the eyelid through the optic nerve, and the acoustic vibrations are vibrated by the diaphragm and the vertical vibration of the connector. , And the stretching vibration of the polymer piezoelectric film is captured, and the stretching vibration is extracted as an electric signal by the piezoelectricity of the film, and the presence or absence of a cerebrovascular disorder is determined.
［実施例］ 次に、本発明を図示の実施例に基き更に詳細に説明す
るが、本発明はこれらの実施例に限られるものではな
い。[Examples] Next, the present invention will be described in more detail based on the illustrated examples, but the present invention is not limited to these examples.
第１図は本発明の生体音響変換器の一実施例を示す内
部平面図、第２図は同上横断面概要図、第３図は生体音
響変換器の部分断面概要図である。FIG. 1 is an internal plan view showing an embodiment of the bioacoustic transducer of the present invention, FIG. 2 is a schematic cross-sectional view of the same, and FIG. 3 is a partial cross-sectional schematic view of the bioacoustic transducer.
本発明の生体音響変換器は、図に示すように、上方部
（一端部）７は閉ざされ底部（他端部）８は開口された
箱体（ケース）１の開口部10に、弾性材料よりなる振動
板２を取り付ける。振動板２の中央部には結合子３を固
定し、結合子３の上端を屈曲部として、延伸方向を長手
方向とする帯状の高分子圧電フィルム５が張設される。
また、この高分子圧電フィルム５の両端部９は、押え板
４により箱体１の底部８の周囲に固定される。そして、
高分子圧電フィルム５はコネクター６にリード線11にて
接続する。As shown in the figure, the bioacoustic transducer of the present invention has an upper part (one end) 7 closed and a bottom part (other end) 8 opened at an opening 10 of a box (case) 1 having an elastic material. The vibration plate 2 is attached. A connector 3 is fixed to the central portion of the diaphragm 2, and a band-shaped polymer piezoelectric film 5 having the upper end of the connector 3 as a bent portion and extending in the longitudinal direction is stretched.
Both ends 9 of the polymer piezoelectric film 5 are fixed around the bottom 8 of the box 1 by the holding plate 4. And
The polymer piezoelectric film 5 is connected to the connector 6 by a lead wire 11.
上記のような構成の生体音響変換器において、振動板
２の外表面を人のまぶたの上に配置することにより、脳
血管の障害部で発生した音響振動は、血流に伴なって頭
蓋内の視神経束、眼球等を通してまぶたに伝わり、まぶ
たの振動は振動板２を振動させる。振動板２の振動は振
動板２に固定された結合子３を上下振動させ、更に結合
子３に固定された高分子圧電フィルム５に伝わって高分
子圧電フィルム５の伸縮振動になる。そして、高分子圧
電フィルム５の伸縮振動は高分子圧電フィルム５の圧電
性により電気信号として取り出され、コネクター６を経
て図示しない外部の周波数解析装置等の測定・計測装置
に送られ、その周波数スペクトルにより動脈瘤の有無が
検知されることになる。In the bioacoustic transducer having the above-described configuration, by arranging the outer surface of the diaphragm 2 on the eyelid of a person, the acoustic vibration generated in the cerebral blood vessel obstruction is caused by intracranial blood flow. Is transmitted to the eyelid through the optic nerve bundle, the eyeball, and the like, and the vibration of the eyelid causes the diaphragm 2 to vibrate. The vibration of the vibration plate 2 causes the connector 3 fixed to the vibration plate 2 to vibrate up and down, and further propagates to the polymer piezoelectric film 5 fixed to the connector 3 to cause the polymer piezoelectric film 5 to expand and contract. The stretching vibration of the polymer piezoelectric film 5 is taken out as an electric signal by the piezoelectricity of the polymer piezoelectric film 5, sent to an external measurement / measurement device such as a frequency analyzer (not shown) via a connector 6, and its frequency spectrum is measured. As a result, the presence or absence of an aneurysm is detected.
本発明の生体音響変換器に使用される振動板２として
は、弾性のあるポリカーボネート、アクリル樹脂、ポリ
エステル、ポリエステル繊維強化エポキシ樹脂、および
炭素繊維強化高分子材料等が使用され、その厚さは0.05
〜0.5mmが好ましい。振動板２の厚さが0.05mm未満の場
合には最大感度周波数が低くなりずぎること、及び振動
版が変形し易いので結合子を保持するのに十分な機械強
度を得られないので破壊され易くなる。一方、0.5mmを
超えると、最大感度周波数が高くなりすぎ、それに伴っ
て感度が低下する。また、振動板２として用いる弾性材
料のヤング率は１×109（N/m2）〜5.0×1010（N/m2）が
好ましい。As the diaphragm 2 used in the bioacoustic transducer of the present invention, elastic polycarbonate, acrylic resin, polyester, polyester fiber reinforced epoxy resin, carbon fiber reinforced polymer material, or the like is used, and the thickness thereof is 0.05.
~ 0.5 mm is preferred. If the thickness of the diaphragm 2 is less than 0.05 mm, the maximum sensitivity frequency becomes low and the diaphragm is easily deformed, so that the mechanical strength cannot be obtained enough to hold the connector. It will be easier. On the other hand, if it exceeds 0.5 mm, the maximum sensitivity frequency becomes too high, and the sensitivity decreases accordingly. The elastic material used as the diaphragm 2 preferably has a Young's modulus of 1 × 10 9 (N / m 2 ) to 5.0 × 10 10 (N / m 2 ).
ここで、振動板２は形状が円形で、その直径が10〜40
mmであることが好ましい。円形でない場合には、単一周
波数の振動モードとならないため、得られる生体音響変
換器の周波数特性が乱れるという不都合がある。また、
振動板２の直径が10mm未満の場合には、振動板が小さい
ため生体音響変換器の最大感度周波数が高くなり過ぎ、
必要領域での感度が低下する。一方、40mmを超えると、
眼窩より大きくなり全くまぶたと接触しないという問題
が生じる。The diaphragm 2 has a circular shape and a diameter of 10 to 40.
It is preferably mm. If the shape is not circular, a single-frequency vibration mode will not be obtained, and there is a disadvantage that the frequency characteristics of the obtained bioacoustic transducer are disturbed. Also,
When the diameter of the diaphragm 2 is less than 10 mm, the maximum sensitivity frequency of the bioacoustic transducer becomes too high because the diaphragm is small,
The sensitivity in the required area decreases. On the other hand, if it exceeds 40 mm,
The problem is that the eyelids are larger than the orbit and do not come into contact with the eyelids at all.
また、本発明において、伸縮振動のエネルギーを電気
的信号に変換する特性を有する高分子圧電フィルムとし
ては、ポリフッ化ビニリデン（PVDF）、PVDFとトリクロ
ロエチレンの共重合体等の延伸フィルムが使用され、こ
れを延伸方向を長手方向として使用する。その膜厚は0.
005〜0.1mmが好ましい。In the present invention, a stretched film such as polyvinylidene fluoride (PVDF) or a copolymer of PVDF and trichloroethylene is used as the polymer piezoelectric film having the property of converting the energy of stretching vibration into an electric signal. Is used as the stretching direction. Its film thickness is 0.
005 to 0.1 mm is preferred.
本発明において、振動板と高分子圧電フィルムを連結
する結合子の材質はアルミニウム、アクリル樹脂等が使
用される。尚、結合子の質量は0.1〜3gの範囲にあるこ
とが好ましい。その理由は、上記の如く生体音響変換器
の振動糸を軽くすると、生体上での振動状態を変えるこ
となく効率良く振動を検出できるからである。In the present invention, aluminum, acrylic resin, or the like is used as a material of a connector for connecting the diaphragm and the polymer piezoelectric film. Incidentally, the mass of the connector is preferably in the range of 0.1 to 3 g. The reason is that if the vibration yarn of the bioacoustic transducer is lightened as described above, the vibration can be detected efficiently without changing the vibration state on the living body.
更に、第３図に示す振動板と高分子圧電フィルムで形
成される取付角θは５°〜30°であることが好ましい。
取付角θが５°未満の場合には、温度、湿度の変化によ
るPVDFの伸びにより感度の変化の影響が大きくなるため
好ましくない。また、取付角θが30°を超えると結合子
の振動によって生じるPVDFへの引張応力が小さくなり、
感度低下を来たすため好ましくない。Further, the mounting angle θ formed by the diaphragm and the polymer piezoelectric film shown in FIG. 3 is preferably 5 ° to 30 °.
When the mounting angle θ is less than 5 °, it is not preferable because the effect of the change in sensitivity increases due to the expansion of the PVDF due to the change in temperature and humidity. If the mounting angle θ exceeds 30 °, the tensile stress on the PVDF caused by the vibration of the connector decreases,
It is not preferable because the sensitivity is lowered.
なお、本発明の生体音響変換器の音圧に対する最大感
度周波数、および装着時の最大感度周波数は200Hz〜2.5
kHzが好ましい。Note that the maximum sensitivity frequency for the sound pressure of the bioacoustic transducer of the present invention, and the maximum sensitivity frequency at the time of wearing are 200 Hz to 2.5.
kHz is preferred.
以下、本発明のさらに具体的な実施結果を説明する。 Hereinafter, more specific implementation results of the present invention will be described.
（実施例） 直径40mm、厚さ10mmの箱体１の開口部10にポリエステ
ル繊維強化エポキシ樹脂からなる振動板２をエポキシ系
樹脂にて貼付した。そして、振動板２とポリフッ化ビニ
リデンからなる高分子圧電フィルム５とを、アクリル製
の結合子３にてカップリングした。尚、振動板の直径は
20mmとした。(Example) A diaphragm 2 made of a polyester fiber reinforced epoxy resin was adhered to an opening 10 of a box 1 having a diameter of 40 mm and a thickness of 10 mm with an epoxy resin. Then, the vibration plate 2 and the high-molecular piezoelectric film 5 made of polyvinylidene fluoride were coupled by an acrylic connector 3. The diameter of the diaphragm is
20 mm.
このように構成した生体音響変換器を用いて被検者の
動脈瘤の有無を検査したところ、動脈瘤を有する患者と
動脈瘤を有さない患者とを周波数解析装置による周波数
スペクトルにより明確に区別することができた。Using the bioacoustic transducer configured in this way, the subject was examined for the presence or absence of an aneurysm, and patients with aneurysms and patients without aneurysms were clearly distinguished by the frequency spectrum using a frequency analyzer. We were able to.
［発明の効果］ 以上説明したように、本発明の生体音響変換器は、ま
ぶたの外表面へ伝わってくる血流雑音の音響振動を振動
板の振動変位を圧電フィルムにより電気変換して出力す
るため、非侵襲で短時間に簡便に測定でき、安価である
ほか、感度がよく雑音も入り難く、脳動脈瘤の検出装置
として極めて効果的である。[Effects of the Invention] As described above, the bioacoustic transducer of the present invention outputs the acoustic vibration of the blood flow noise transmitted to the outer surface of the eyelid by electrically converting the vibration displacement of the diaphragm using the piezoelectric film. Therefore, it is non-invasive, can be measured easily in a short time, is inexpensive, has high sensitivity, is hard to generate noise, and is extremely effective as a cerebral aneurysm detection device.
第１図は本発明の生体音響変換器の一例の内部平面図、
第２図は同上横断面概要図、第３図は生体音響変換器の
部分断面概要図である。 １……箱体、２……振動板、３……結合子、５……高分
子圧電フィルム。FIG. 1 is an internal plan view of an example of the bioacoustic transducer of the present invention,
FIG. 2 is a schematic cross-sectional view of the same, and FIG. 3 is a partial cross-sectional schematic view of a bioacoustic transducer. DESCRIPTION OF SYMBOLS 1 ... Box, 2 ... Vibration plate, 3 ... Connector, 5 ... Polymer piezoelectric film.
Claims (2)
体の開口部に、厚さ0.05〜0.5mmの弾性材料よりなる振
動板を取付けるとともに、延伸方向が長手方向である帯
状の高分子圧電フィルムの両端を該箱体の開口部に取付
け、かつ前記振動板の中央部と該高分子圧電フィルムの
中央部とを小片からなる結合子にて結合することによ
り、音響振動を、前記振動板の振動、前記結合子の上下
振動、及び前記高分子圧電フィルムの伸縮振動を介して
捕らえ、この伸縮振動を前記高分子圧電フィルムの圧電
性により電気信号として取り出すことを特徴とする生体
音響変換器。1. A belt made of an elastic material having a thickness of 0.05 to 0.5 mm is attached to an opening of a box body having one end closed and the other end opened, and a stretching direction is a longitudinal direction. By attaching both ends of the polymer piezoelectric film to the opening of the box, and connecting the center part of the diaphragm and the center part of the polymer piezoelectric film with a connector composed of small pieces, acoustic vibration is reduced. The vibration is captured through vibration of the diaphragm, vertical vibration of the connector, and expansion and contraction vibration of the polymer piezoelectric film, and the expansion and contraction vibration is extracted as an electric signal by the piezoelectricity of the polymer piezoelectric film. Bioacoustic transducer.
る角度が５°〜30°である請求項１記載の生体音響変換
器。2. The bioacoustic transducer according to claim 1, wherein the angle formed between the diaphragm and the polymer piezoelectric film is 5 ° to 30 °.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2245752A JP2719038B2 (en) | 1990-09-14 | 1990-09-14 | Bioacoustic transducer |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2245752A JP2719038B2 (en) | 1990-09-14 | 1990-09-14 | Bioacoustic transducer |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH04126135A JPH04126135A (en) | 1992-04-27 |
| JP2719038B2 true JP2719038B2 (en) | 1998-02-25 |
Family
ID=17138272
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2245752A Expired - Fee Related JP2719038B2 (en) | 1990-09-14 | 1990-09-14 | Bioacoustic transducer |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2719038B2 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6261237B1 (en) * | 1998-08-20 | 2001-07-17 | Medacoustics, Inc. | Thin film piezoelectric polymer sensor |
| US7037268B1 (en) | 1999-03-01 | 2006-05-02 | Medacoustics, Inc. | Low profile acoustic sensor arry and sensors with pleated transmission lines and related methods |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5122293A (en) * | 1974-08-16 | 1976-02-21 | Sanei Sokki Kk | CHOSHINMAIKURO FUON |
| JPS63146604U (en) * | 1987-03-16 | 1988-09-27 |
-
1990
- 1990-09-14 JP JP2245752A patent/JP2719038B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH04126135A (en) | 1992-04-27 |
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| Date | Code | Title | Description |
|---|---|---|---|
| LAPS | Cancellation because of no payment of annual fees |