JP2685861B2 - Ultrasonic transducer - Google Patents
Ultrasonic transducerInfo
- Publication number
- JP2685861B2 JP2685861B2 JP63326549A JP32654988A JP2685861B2 JP 2685861 B2 JP2685861 B2 JP 2685861B2 JP 63326549 A JP63326549 A JP 63326549A JP 32654988 A JP32654988 A JP 32654988A JP 2685861 B2 JP2685861 B2 JP 2685861B2
- Authority
- JP
- Japan
- Prior art keywords
- wave
- ultrasonic
- receiver
- transmitter
- wave transmitter
- 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
Landscapes
- Measurement Of Velocity Or Position Using Acoustic Or Ultrasonic Waves (AREA)
Description
【発明の詳細な説明】 〔産業上の利用分野〕 この発明は、車の警報器等に使用する超音波送受波器
に関するものである。Description: TECHNICAL FIELD The present invention relates to an ultrasonic wave transmitter / receiver used for a vehicle alarm or the like.
従来、第７図に示すように、社内に超音波警報器Ａを
セットし、社内に超音波を充満させ、外部から人が侵入
するとドップラー効果によって人体の移動を検知して警
報を発生している。Conventionally, as shown in FIG. 7, the ultrasonic alarm device A is set in the company to fill the company with ultrasonic waves, and when a person enters from the outside, the movement of the human body is detected by the Doppler effect and an alarm is generated. There is.
超音波警報器Ａとしては、第８図に示すような超音波
送受波器50が使用されている。超音波送受波器50は、ハ
ウジング51内に超音波送波器52ならびに受波器53を支持
具54にて固設し、ハウジング51の音の出入り口は飾り綱
カバー55で覆い、かつハウジング50内に回路ブロック56
を設置して構成されている。回路ブロック56では、送波
と受波の周波数の差を検知し、周波数差があると警報を
発生する。As the ultrasonic alarm device A, an ultrasonic wave transmitter / receiver 50 as shown in FIG. 8 is used. The ultrasonic wave transmitter / receiver 50 has an ultrasonic wave transmitter 52 and a wave receiver 53 fixed in a housing 51 by a support member 54, and the sound inlet / outlet of the housing 51 is covered with a decorative rope cover 55, and the housing 50 Circuit block in 56
It is configured to be installed. The circuit block 56 detects the difference between the frequencies of the transmitted wave and the received wave, and issues an alarm if there is a frequency difference.
しかし、このように構成された超音波送受波器50で
は、送波器52から送出された超音波の一部が飾り綱カバ
ー55で反射し、受波器53で受波されてしまったり、支持
具54ならびにハウジング51を介して送波器52から受波器
53へ超音波が伝播してしまうという問題があった。However, in the ultrasonic wave transmitter / receiver 50 configured in this way, a part of the ultrasonic wave transmitted from the wave transmitter 52 is reflected by the decorative rope cover 55 and is received by the wave receiver 53. From the transmitter 52 to the receiver via the support 54 and the housing 51
There was a problem that ultrasonic waves propagate to 53.
すなわち、送出した超音波周波数ｆが移動物体で反射
してもどってきた反射波の周波数をｆ′とすると、 ｆ′−ｆ＝２・Ｖ・f/C （Ｖ＝移動物体の速度、Ｃ＝音速） となるが、受波器53に周波数ｆ′の反射波が受波される
以上に周波数ｆの送波が受波されると、回路ブロック56
にて送波によるレベルが飽和してしまい受波の処理能力
が低下し、移動物体の検知能力が低下する。つまり、検
知エリアが小さくなってしまうという欠点があった。That is, when the transmitted ultrasonic frequency f is reflected by a moving object and the frequency of the reflected wave is f ′, f′−f = 2 · V · f / C (V = moving object velocity, C = Sound wave velocity), but if the wave receiver 53 receives the transmitted wave of the frequency f more than the reflected wave of the frequency f ′ is received, the circuit block 56
At, the level of the transmitted wave is saturated and the processing ability of the received wave is reduced, and the detection ability of the moving object is reduced. That is, there is a drawback that the detection area becomes small.
したがって、この発明の目的は、送波器から受波器へ
超音波が直接回り込むのを防止した超音波送受波器を提
供することである。Therefore, an object of the present invention is to provide an ultrasonic wave transmitter / receiver which prevents ultrasonic waves from directly flowing from the wave transmitter to the wave receiver.
この発明の超音波送受波器は、超音波出口および超音
波入口を有しこの超音波出口および超音波入口に対応し
て内部に筒状の支持体を設けるとともに検知器を収容し
た本体と、支持体に嵌入し超音波出口および超音波入口
に臨ませて本体内に設けた送波器および受波器とを備
え、送波器および受波器の少なくとも一方の支持体の内
周面に周方向に延びる突条部を形成し、突条部を形成し
た支持体と送波器または受波器との間に外面に複数の弾
性突部を有する弾性体を介在させたことを特徴とするも
のである。The ultrasonic transmitter / receiver of the present invention has an ultrasonic outlet and an ultrasonic inlet, and a main body accommodating a detector with a cylindrical support provided inside thereof corresponding to the ultrasonic outlet and the ultrasonic inlet, A wave transmitter and a wave receiver which are fitted in the support body and are provided in the main body so as to face the ultrasonic wave outlet and the ultrasonic wave inlet, and are provided on the inner peripheral surface of at least one of the wave transmitter and the wave receiver. A protrusion extending in the circumferential direction is formed, and an elastic body having a plurality of elastic protrusions on the outer surface is interposed between the support having the protrusion and the wave transmitter or the wave receiver. To do.
この発明の超音波送受波器によると、送波器ならびに
受波器を本体に別々に形成した超音波出口ならびに超音
波入口に設置したことにより、送波器から送出された超
音波が本体内で反射して直接受波器で受波されるのを防
ぐことができる。さらに、送波器および受波器の少なく
とも一方を、内周面に周方向に延びる突条部を形成した
支持体の内部に嵌入し、かつ送波器または受波器と支持
体の内周面との間に、外面に複数の弾性突部を有する弾
性体を介在したので、本体を介して送波器から受波器へ
超音波が伝播するのを弾性体にて吸収でき、しかも突条
部がショックアブソーバとして作用すると共に、弾性突
部と突条部とが点接触して超音波が伝播し難くなる。こ
のようにして、送波器から受波器へ超音波が直接回り込
むのを防止できる。According to the ultrasonic wave transmitter / receiver of the present invention, the ultrasonic wave transmitted from the wave transmitter is provided inside the main body by installing the wave transmitter and the wave receiver at the ultrasonic wave outlet and the ultrasonic wave inlet formed separately in the main body. It is possible to prevent the reflected wave from being directly received by the wave receiver. Further, at least one of the wave transmitter and the wave receiver is fitted into the inside of a support body having a ridge portion extending in the circumferential direction on the inner peripheral surface, and the inner circumference of the wave transmitter or the wave receiver and the support body. Since the elastic body having a plurality of elastic protrusions on the outer surface is interposed between the surface and the surface, the elastic body can absorb the propagation of ultrasonic waves from the wave transmitter to the wave receiver through the main body, The ridge acts as a shock absorber, and the elastic protrusion and the ridge make point contact with each other, making it difficult for ultrasonic waves to propagate. In this way, it is possible to prevent ultrasonic waves from directly flowing from the wave transmitter to the wave receiver.
この発明の一実施例を第１図ないし第６図に基づいて
説明する。One embodiment of the present invention will be described with reference to FIGS.
第１図および第２図において、10はハウジングであ
り、上下の分割ハウジング11,12に分割されている。ハ
ウジング10の前面の両端には超音波出口13ならびに超音
波入口14が形成されており、所望のビームを得るために
開けた丸穴とＲ部でホーンを構成している。超音波出口
13ならびに超音波入口14内には、超音波を送波する送波
器15ならびに周波数偏移を受けた超音波を連続的に受波
する受波器16が設けられている。例えば送波器15の場
合、第３図に示すように、送波器15の外周にゴム等の弾
性材料にて形成した環状の弾性体17を外嵌する。弾性体
17の外面には、断面山形状の複数の弾性突部18が突設さ
れている。そして、送波器15の上下から分割支持体19,2
0を外嵌する。分割支持体19,20には半円形の切り込み2
1,22が形成され、各切り込み21,22の内周面には周方向
に延びる突条部23が形成されている。第４図のように、
両分割支持体19,20を突き合わせて支持体33を構成する
と、両切り込み21,22によって嵌合穴24が形成され、こ
の嵌合穴24内に送波器15が嵌合された状態となり、弾性
突部18が突条部23に弾接して送波器15が支持体33で支持
される。なお、受波器16も、送波器15と同様にして支持
体33で支持される。また、第１図に示すように、送波器
15と受波器16の間において、ハウジング10の内面に隔壁
34を設ける。隔壁34は、第５図に示すように、ハウジン
グ構成体11,12の内面にそれぞれ一体成形した上下の分
割隔壁35,36にて構成されている。なお、ハウジング10
と支持体33より本体９が構成されている。In FIGS. 1 and 2, reference numeral 10 denotes a housing, which is divided into upper and lower split housings 11 and 12. An ultrasonic wave outlet 13 and an ultrasonic wave inlet 14 are formed at both ends of the front surface of the housing 10, and a horn is formed by a round hole opened to obtain a desired beam and an R portion. Ultrasonic outlet
Inside the ultrasonic wave inlet 13 and the ultrasonic wave inlet 14, there are provided a wave transmitter 15 for transmitting an ultrasonic wave and a wave receiver 16 for continuously receiving the frequency-shifted ultrasonic wave. For example, in the case of the wave transmitter 15, as shown in FIG. 3, an annular elastic body 17 formed of an elastic material such as rubber is fitted on the outer circumference of the wave transmitter 15. Elastic body
A plurality of elastic protrusions 18 each having a mountain-shaped cross section are provided on the outer surface of the protrusion 17. Then, from above and below the transmitter 15, the divided supports 19, 2
0 is fitted. Semicircular notch 2 on split supports 19, 20
1, 22 are formed, and a ridge 23 extending in the circumferential direction is formed on the inner peripheral surface of each of the notches 21, 22. As shown in Figure 4,
When the support member 33 is formed by abutting the two divided support members 19 and 20, the fitting hole 24 is formed by the notches 21 and 22, and the wave transmitter 15 is fitted in the fitting hole 24. The elastic protrusion 18 elastically contacts the protrusion 23 so that the wave transmitter 15 is supported by the support 33. The wave receiver 16 is also supported by the support 33 in the same manner as the wave transmitter 15. In addition, as shown in FIG.
A partition wall is provided on the inner surface of the housing 10 between the wave receiver 15 and the wave receiver 16.
34 will be provided. As shown in FIG. 5, the partition wall 34 is composed of upper and lower partition walls 35 and 36 integrally formed on the inner surfaces of the housing structural bodies 11 and 12, respectively. The housing 10
The support body 33 constitutes the main body 9.
さらに、ハウジング10内には、ドップラー周波数成分
を回路で処理し移動物体を検知する検知器25が設けられ
ており、検知器25は第６図に示すように構成されてい
る。第６図において、26は一定周波数で発振する発振回
路であり、その出力を増幅回路27で増幅して送波器15か
ら超音波を送出している。また、28は受波器16で受波し
た超音波の電気信号を増幅する増幅回路であり、混合回
路29に入力される。混合回路29では、増幅回路28の出力
と発振回路26の出力との周波数差を検出し、周波数差に
より生じるビートが帯域フィルタ増幅器30に入力され
る。送信周波数と受信周波数とに差がないときには、帯
域フィルタ増幅器30から信号が出力されず、周波数差が
存在する時のみ帯域フィルタ増幅器30から信号が出力さ
れる。帯域フィルタ増幅器30から出力された信号は、出
力駆動回路31に入力され、検知信号を出力する。なお、
増幅回路28,混合回路29,帯域フィルタ増幅器30,出力駆
動回路31にて検知器25を構成しており、検知器25はケー
ブル32（第１図）によって他機器へ接続されている。Further, inside the housing 10, there is provided a detector 25 which processes a Doppler frequency component by a circuit to detect a moving object, and the detector 25 is constructed as shown in FIG. In FIG. 6, reference numeral 26 is an oscillating circuit which oscillates at a constant frequency, the output of which is amplified by an amplifying circuit 27 and an ultrasonic wave is transmitted from a wave transmitter 15. Further, 28 is an amplifier circuit that amplifies the electric signal of the ultrasonic wave received by the wave receiver 16, and is input to the mixing circuit 29. The mixing circuit 29 detects the frequency difference between the output of the amplifier circuit 28 and the output of the oscillator circuit 26, and the beat generated by the frequency difference is input to the bandpass filter amplifier 30. When there is no difference between the transmission frequency and the reception frequency, the band filter amplifier 30 does not output a signal, and the band filter amplifier 30 outputs a signal only when there is a frequency difference. The signal output from the bandpass filter amplifier 30 is input to the output drive circuit 31 and outputs a detection signal. In addition,
The amplifier 25, the mixing circuit 29, the bandpass filter amplifier 30, and the output drive circuit 31 constitute a detector 25, and the detector 25 is connected to another device by a cable 32 (FIG. 1).
このようにしてなる超音波送受波器は、例えば第７図
に示すように、車の警報器Ａとして使用される。The ultrasonic wave transmitter / receiver thus configured is used as a vehicle alarm A as shown in FIG. 7, for example.
この超音波送受波器によると、送波器15ならびに受波
器16をハウジング10に設けた別々の超音波出口13ならび
に超音波入口14に設けたので、従来のように送出された
超音波がカバーで反射して直接受波器で受波されるのを
防ぐことができる。また、送波器15ならびに受波器16の
外周面に支持体33の内周面の突条部23に弾接する弾性突
部18を突設したので、支持体33ならびにハウジング10を
介して送波器15から受波器16へ伝播する超音波をこの弾
性突部18にて吸収できる。このようにして、送波器15か
ら受波器16へ超音波が直接回り込むのを防止でき、検知
器25の検知エリアが小さくなって検知能力が低下するの
を防ぐことができる。しかも、突条部23がショックアブ
ソーバとして作用すると共に、弾性突部18と突条部23と
が点接触して超音波が伝播し難くなる。さらに、送波器
15,受波器16を支持体33で囲んだこと、ならびに送波器1
5と受波器16の間に隔壁34を設けたことによっても、送
波器15から受波器16へ直接超音波が伝播するのを防ぐこ
とができる。このようにして、送波器15から受波器16へ
超音波が直接回り込むのをより一層防止できる。According to this ultrasonic wave transmitter / receiver, since the wave transmitter 15 and the wave receiver 16 are provided in the separate ultrasonic wave outlets 13 and ultrasonic wave inlets 14 provided in the housing 10, the transmitted ultrasonic waves are different from those in the conventional case. It is possible to prevent the waves from being reflected by the cover and directly received by the wave receiver. Further, since the elastic projections 18 that elastically contact the projections 23 on the inner peripheral surface of the support body 33 are provided on the outer peripheral surfaces of the wave transmitter 15 and the wave receiver 16, the wave is transmitted through the support body 33 and the housing 10. Ultrasonic waves propagating from the wave device 15 to the wave receiver 16 can be absorbed by the elastic protrusions 18. In this way, it is possible to prevent the ultrasonic waves from directly flowing from the wave transmitter 15 to the wave receiver 16, and to prevent the detection area of the detector 25 from becoming small and the detection capability from being lowered. Moreover, the ridge 23 acts as a shock absorber, and the elastic ridge 18 and the ridge 23 make point contact with each other, making it difficult for ultrasonic waves to propagate. In addition, the transmitter
15, Surrounding the wave receiver 16 with the support 33, and the wave transmitter 1
Providing the partition wall 34 between the wave receiver 5 and the wave receiver 16 can also prevent the ultrasonic wave from directly propagating from the wave transmitter 15 to the wave receiver 16. In this way, it is possible to further prevent the ultrasonic waves from directly flowing from the wave transmitter 15 to the wave receiver 16.
また、送波器15,受波器16は分割支持体19,20にて挟み
込んで支持する構造になっており、組立て易い。しか
も、弾性突部18が支持体33の内周面に弾接するので、送
波器15,受波器16が嵌合穴24の中心に正しく位置決めさ
れる。Further, the wave transmitter 15 and the wave receiver 16 are structured so as to be supported by being sandwiched between the split supports 19 and 20, which facilitates assembly. Moreover, since the elastic protrusion 18 elastically contacts the inner peripheral surface of the support 33, the wave transmitter 15 and the wave receiver 16 are correctly positioned in the center of the fitting hole 24.
さらに、突条部23は支持体33と同一材料にて形成さ
れ、隔壁24はハウジング10と同一材料にて形成されてい
るので、材料費が安くコストの低減が図れる。Furthermore, since the rib portion 23 is formed of the same material as the support 33 and the partition wall 24 is formed of the same material as the housing 10, the material cost is low and the cost can be reduced.
なお、弾性突部18の数は８個に限らず、かつ形状も山
形に限らず、リブ状のものでなく単なる突起でもよい。
さらに、弾性体17は弾性突部18のみ弾性を有し他の環状
部分は非弾性体であってもよい。しかも、弾性突部18は
送波器15と受波器16の片方のみに設けられていてもよ
い。The number of the elastic projections 18 is not limited to eight, and the shape is not limited to the mountain shape, and may be a simple projection instead of a rib shape.
Further, the elastic body 17 may be elastic only in the elastic protrusion 18, and the other annular portion may be a non-elastic body. Moreover, the elastic protrusion 18 may be provided on only one of the wave transmitter 15 and the wave receiver 16.
なお、前記実施例では、本体９は別体のハウジング10
と支持体33とから構成されていたが、ハウジング10と支
持体33が一体となったものであってもよい。In the above embodiment, the main body 9 is a separate housing 10.
However, the housing 10 and the support 33 may be integrated.
この発明の超音波送受波器によると、送波器ならびに
受波器を本体に別々に形成した超音波出口ならびに超音
波入口に設置したことにより、送波器から送出された超
音波が本体内で反射して直接受波器で受波されるのを防
ぐことができる。さらに、送波器および受波器の少なく
とも一方を、内周面に周方向に延びる突条部を形成した
支持体の内部に嵌入し、かつ送波器または受波器と支持
体の内周面との間に、外面に複数の弾性突部を有する弾
性体を介在したので、本体を介して送波器から受波器へ
超音波が伝播するのを弾性体にて吸収でき、しかも突条
部がショックアブソーバとして作用すると共に、弾性突
部と突条部とが点接触して超音波が伝播し難くなる。こ
のようにして、送波器から受波器へ超音波が直接回り込
むのを防止できるという効果が得られる。According to the ultrasonic wave transmitter / receiver of the present invention, the ultrasonic wave transmitted from the wave transmitter is provided inside the main body by installing the wave transmitter and the wave receiver at the ultrasonic wave outlet and the ultrasonic wave inlet formed separately in the main body. It is possible to prevent the reflected wave from being directly received by the wave receiver. Further, at least one of the wave transmitter and the wave receiver is fitted into the inside of a support body having a ridge portion extending in the circumferential direction on the inner peripheral surface, and the inner circumference of the wave transmitter or the wave receiver and the support body. Since the elastic body having a plurality of elastic protrusions on the outer surface is interposed between the surface and the surface, the elastic body can absorb the propagation of ultrasonic waves from the wave transmitter to the wave receiver through the main body, The ridge acts as a shock absorber, and the elastic protrusion and the ridge make point contact with each other, making it difficult for ultrasonic waves to propagate. In this way, it is possible to obtain the effect that it is possible to prevent ultrasonic waves from directly flowing from the wave transmitter to the wave receiver.
第１図はこの発明の一実施例の平面図、第２図はその側
面図、第３図はその部分分解斜視図、第４図はその部分
正面図、第５図は第１図のＶ−Ｖ断面図、第６図はその
検知器のブロック図、第７図は超音波警報器を設置した
車の平面図、第８図は従来例の斜視図である。 ９…本体、13…超音波出口、14…超音波入口、15…送波
器、16…受波器、17…弾性体、18…弾性突部、24…嵌合
穴、25…検知器1 is a plan view of an embodiment of the present invention, FIG. 2 is a side view thereof, FIG. 3 is a partially exploded perspective view thereof, FIG. 4 is a partial front view thereof, and FIG. 5 is V of FIG. -V sectional view, FIG. 6 is a block diagram of the detector, FIG. 7 is a plan view of a vehicle in which an ultrasonic alarm is installed, and FIG. 8 is a perspective view of a conventional example. 9 ... Main body, 13 ... Ultrasonic outlet, 14 ... Ultrasonic inlet, 15 ... Wave transmitter, 16 ... Wave receiver, 17 ... Elastic body, 18 ... Elastic protrusion, 24 ... Fitting hole, 25 ... Detector
Claims (1)
音波出口および超音波入口に対応して内部に筒状の支持
体を設けるとともに検知器を収容した本体と、前記支持
体に嵌入し前記超音波出口および超音波入口に臨ませて
前記本体内に設けた送波器および受波器とを備え、 前記送波器および受波器の少なくとも一方の支持体の内
周面に周方向に延びる突条部を形成し、前記突条部を形
成した支持体と前記送波器または受波器との間に外面に
複数の弾性突部を有する弾性体を介在させたことを特徴
とする超音波送受波器。1. A main body accommodating a detector and a tubular body having an ultrasonic outlet and an ultrasonic inlet, which are provided in the inside corresponding to the ultrasonic outlet and the ultrasonic inlet, and are fitted into the support. And a wave transmitter and a wave receiver provided inside the main body so as to face the ultrasonic wave outlet and the ultrasonic wave inlet, respectively, and the inner peripheral surface of at least one support of the wave transmitter and the wave receiver is surrounded. Characterized in that a ridge portion extending in the direction is formed, and an elastic body having a plurality of elastic ridges on the outer surface is interposed between the support body having the ridge portion and the wave transmitter or the wave receiver. And an ultrasonic transducer.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63326549A JP2685861B2 (en) | 1988-12-23 | 1988-12-23 | Ultrasonic transducer |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63326549A JP2685861B2 (en) | 1988-12-23 | 1988-12-23 | Ultrasonic transducer |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH02170083A JPH02170083A (en) | 1990-06-29 |
| JP2685861B2 true JP2685861B2 (en) | 1997-12-03 |
Family
ID=18189068
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP63326549A Expired - Fee Related JP2685861B2 (en) | 1988-12-23 | 1988-12-23 | Ultrasonic transducer |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2685861B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2002128474A (en) * | 2000-10-27 | 2002-05-09 | Furukawa Co Ltd | Over-hoisting detecting device for crane |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP5471247B2 (en) * | 2009-09-30 | 2014-04-16 | 日本精工株式会社 | Sensor fixture |
| JP5987437B2 (en) * | 2012-04-18 | 2016-09-07 | マツダ株式会社 | Intrusion detection device for automobiles |
| JP7354639B2 (en) * | 2019-07-18 | 2023-10-03 | 株式会社デンソー | ultrasonic sensor |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5212458Y2 (en) * | 1972-02-28 | 1977-03-18 | ||
| JPS60252284A (en) * | 1984-05-29 | 1985-12-12 | Nissan Motor Co Ltd | Ultrasonic sensor |
| JPS61155975A (en) * | 1984-12-28 | 1986-07-15 | Fujitsu Ten Ltd | Ultrasonic sensor |
-
1988
- 1988-12-23 JP JP63326549A patent/JP2685861B2/en not_active Expired - Fee Related
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2002128474A (en) * | 2000-10-27 | 2002-05-09 | Furukawa Co Ltd | Over-hoisting detecting device for crane |
| JP4624539B2 (en) * | 2000-10-27 | 2011-02-02 | 古河機械金属株式会社 | Crane overload detection device |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH02170083A (en) | 1990-06-29 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| LAPS | Cancellation because of no payment of annual fees |