JPH09152325A - Ultrasonic thickness gage with inhibit gate - Google Patents
Ultrasonic thickness gage with inhibit gateInfo
- Publication number
- JPH09152325A JPH09152325A JP33434495A JP33434495A JPH09152325A JP H09152325 A JPH09152325 A JP H09152325A JP 33434495 A JP33434495 A JP 33434495A JP 33434495 A JP33434495 A JP 33434495A JP H09152325 A JPH09152325 A JP H09152325A
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- Prior art keywords
- gate
- echo
- noise
- threshold
- level
- 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.)
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Landscapes
- Length Measuring Devices Characterised By Use Of Acoustic Means (AREA)
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、禁止ゲート付超音
波厚さ計に係り、特に高温腐食や摩耗等により減肉した
熱交換器管の厚さを測定するために好適に用いられる超
音波厚さ計に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic thickness gauge with a forbidden gate, and particularly to an ultrasonic wave which is preferably used for measuring the thickness of a heat exchanger tube whose thickness has been reduced due to high temperature corrosion or wear. Regarding thickness gauge.
【０００２】[0002]
【従来の技術】図３に、熱交換器管の内側から超音波を
利用して厚さを測定する場合の原理を示す。一般に図３
（Ａ）〜（Ｂ）に示すように、管３の内側から厚さを測
定する場合、水４を媒体として管内表面３ａに対し垂直
に、送受波部１を介して超音波２を入射させ管内表面エ
コー（Ｓエコー）と管外表面エコー（Ｂエコー）の間の
時間ｔを計測し、これに管材の音速を乗ずることにより
厚さの測定が可能となる。2. Description of the Related Art FIG. 3 shows the principle of measuring the thickness from the inside of a heat exchanger tube using ultrasonic waves. Figure 3 in general
As shown in (A) to (B), when the thickness is measured from the inside of the pipe 3, the ultrasonic wave 2 is made to enter the pipe inner surface 3a perpendicularly to the pipe inner surface 3a using the water 4 as a medium. The thickness t can be measured by measuring the time t between the surface echo inside the tube (S echo) and the surface echo outside the tube (B echo) and multiplying it by the sound velocity of the pipe material.
【０００３】[0003]
【発明が解決しようとする課題】しかしながら、管３の
局部減肉部５では図３（Ｃ）に示すように管外表面３ｂ
からの反射エネルギーが著しく低下するので、探触子１
Ａの送受波部１で受波したＢエコーの高さが検出回路側
の禁止ゲートの閾値レベルに達せず、厚さ測定が行われ
ない。However, in the locally thinned portion 5 of the pipe 3, as shown in FIG.
The reflected energy from the
The height of the B echo received by the A wave transmitting / receiving unit 1 does not reach the threshold level of the inhibition gate on the detection circuit side, and the thickness measurement is not performed.
【０００４】そのため一般の超音波厚さ計は段階的に受
波感度を上げる機能（オートゲインコントロール）を有
しており局部減肉部５（管外表面３ｂ）からの反射エコ
ー高さが一定のレベルに達したときに管内表面３ａエコ
ー（Ｓエコー）と管外表面３ｂエコー（Ｂエコー）との
間（以下、Ｓ−Ｂ間と称する）の時間ｔを計測するよう
になっているが、図３（Ｃ）に示すようにこの種の超音
波厚さ計は局部減肉部５からの反射エコー（Ｂエコー）
の高さが、ノイズレベルと大差ない場合、図４（ａ）〜
（ｃ）に示すようにノイズにもオートゲインが作用し、
閾値Ｌ’を越えた最もＳエコー寄りのエコーを時間計測
の対象とするため、図４の（ａ）、（ｂ）、（ｃ）の各
パターンの様に管内表面３ａエコーとノイズ間（以下、
Ｓ−Ｎ間と称す）の時間ｔ’を計測し間違った厚さを表
示することとなる。Therefore, a general ultrasonic thickness gauge has a function (auto gain control) of stepwise increasing the receiving sensitivity, and the height of the reflection echo from the locally thinned portion 5 (external surface 3b) is constant. Although the time t between the inner surface 3a echo (S echo) and the outer surface 3b echo (B echo) of the tube (hereinafter, referred to as S-B) is measured when the level is reached. As shown in FIG. 3 (C), the ultrasonic thickness gauge of this type has a reflection echo (B echo) from the locally thinned portion 5.
4 (a)-
As shown in (c), the auto gain also acts on the noise,
Since the echo closest to the S echo that exceeds the threshold L ′ is targeted for time measurement, as shown in each of the patterns of FIGS. ,
The time t ′ (referred to as SN) will be measured and an incorrect thickness will be displayed.
【０００５】本発明は、この様な事情に鑑みて提案され
たもので、超音波受波信号（反射エコー）の反射エネル
ギーが極端に低下する局部減肉部の厚さ測定において管
外表面エコーとノイズとが識別可能な超音波厚さ計を提
供することを目的とする。The present invention has been proposed in view of the above circumstances, and an external surface echo in the thickness measurement of a locally thinned portion where the reflected energy of an ultrasonic wave received signal (reflected echo) is extremely lowered. An object of the present invention is to provide an ultrasonic thickness gauge capable of distinguishing between noise and noise.
【０００６】[0006]
【課題を解決するための手段】受波信号（反射エコー）
の測定波形上に現われるノイズは信号ケーブル内での反
射が原因である。そのため、信号ケーブルの長さにより
現われる位置が決まり、形状とレベルは信号ケーブルと
探触子の種類により変わる。[Means for Solving the Problem] Received signal (reflection echo)
The noise that appears on the measured waveform of is due to reflection in the signal cable. Therefore, the position of the signal cable is determined by the length of the signal cable, and the shape and level of the signal cable and the probe are changed.
【０００７】本発明は、このようなノイズの性質に着目
したもので、測定波形よりノイズと受波（エコー）信号
を識別するために禁止ゲートを有効に利用して、前記測
定波形のノイズ発生域に該ノイズの形状に合わせて、前
記禁止ゲートの立上り位置、閾値高さ及び閾値幅が、調
整可能な多段レベル状の禁止ゲートを設け、この禁止ゲ
ート内のノイズ信号を無視して測定可能に構成するとと
もに、前記ノイズ発生域から外れた区域のゲート閾値レ
ベルを下げ、好ましくは測定波形画面上の基線近傍まで
閾値レベルを下げて前記多段レベル状の禁止ゲートを形
成したことを特徴とするものである。The present invention focuses on the nature of such noise, and effectively uses the inhibition gate to distinguish the noise and the received (echo) signal from the measured waveform to generate the noise of the measured waveform. A multi-level level prohibit gate with adjustable rise position, threshold height and threshold width of the prohibit gate according to the shape of the noise is provided in the region, and noise signals in this prohibit gate can be ignored for measurement. In addition, the gate threshold level of the area deviating from the noise generation area is lowered, and preferably the threshold level is lowered to near the baseline on the measurement waveform screen to form the multi-level inhibition gate. It is a thing.
【０００８】従って本発明の超音波厚さ計は、ノイズの
形状に合わせて測定波形のノイズ発生域の禁止ゲートの
立上り位置と閾値レベル（測定波形の局部減肉部５を含
む管外表面エコー（Ｂエコー）高さの閾値）及び閾値幅
を各段毎に変えられ、ノイズと関係のない残りの禁止ゲ
ートは、測定波形のディスプレーの基線近傍まで閾値を
下げられるので、局部減肉部５のように、反射エコーの
高さが低下する部位でも、ノイズに関係なく管３の厚さ
測定が可能であるとともに、必ずしもオートゲインコン
トロール機能を設ける必要がなく、測定機器のコスト低
減につながる。Therefore, according to the ultrasonic thickness gauge of the present invention, the rising position of the forbidden gate in the noise generation region of the measurement waveform and the threshold level (the external surface echo including the local thinned portion 5 of the measurement waveform) are matched with the shape of the noise. (B echo) Height threshold value) and threshold width can be changed for each step, and the remaining forbidden gates not related to noise can be lowered to the vicinity of the baseline of the display of the measurement waveform. As described above, it is possible to measure the thickness of the tube 3 irrespective of noise even at a portion where the height of the reflected echo is reduced, and it is not always necessary to provide an automatic gain control function, which leads to cost reduction of the measuring device.
【０００９】[0009]
【発明の実施の形態】以下、本発明の実施の形態を、図
示例と共に説明する。ただし、この実施形態に記載され
ている構成部品の寸法、形状、その相対的位置等は特に
特定的な記載がないかぎりは、この発明の範囲をそれに
限定する趣旨ではなく、単なる説明例にすぎない。本発
明の禁止ゲート付超音波厚さ計の一実施例を図１、図
２、図５、図６を参照して説明すると、図１は、超音波
厚さ計の禁止ゲートの説明図、図２は、禁止ゲートの具
体的な調整要領、図５は前記禁止ゲートを生成するため
の超音波厚さ計の要部回路ブロック図、図６は前記回路
の動作手順を示すフローチャート図である。Embodiments of the present invention will be described below with reference to the drawings. However, unless otherwise specified, the dimensions, shapes, relative positions, etc. of the components described in this embodiment are not intended to limit the scope of the present invention thereto, but are merely illustrative examples. Absent. An embodiment of an ultrasonic thickness gauge with a prohibition gate of the present invention will be described with reference to FIGS. 1, 2, 5, and 6. FIG. 1 is an explanatory view of a prohibition gate of the ultrasonic thickness gauge, FIG. 2 is a specific procedure for adjusting the prohibition gate, FIG. 5 is a circuit block diagram of a main part of an ultrasonic thickness gauge for generating the prohibition gate, and FIG. 6 is a flowchart showing an operation procedure of the circuit. .
【００１０】図５において、１Ａは送／受波部１を具え
た探触子、１０は前記送受波部の制御回路、１１は前記
制御回路を介して受波部よりの測定波形を検出する受波
検出回路で、管内表面エコーＳ検出の為の禁止ゲート
（Ｓゲート）を生成するＳゲート生成回路１２、管外表
面エコーＳ検出とノイズＮ除去の為の禁止ゲート（Ｂゲ
ート）を生成するＢゲート生成回路１３、及びタイマ回
路１４が付設されている。１５は管内タイマ回路よりの
クロックに基づいて、表面エコー（Ｓエコー）と管外表
面エコー（Ｂエコー）の間の時間ｔを計測し、これに管
材の音速を乗ずることにより厚さの測定を行うための演
算回路である。１６は前記測定波形及び禁止ゲート等を
表示するためのブラウン管その他のディスプレー、１７
はコントローラである。尚、Ｂゲート生成回路１３はコ
ントローラ１７よりの指示によりＢゲートの多段レベル
状の禁止ゲートの閾値レベルや閾値幅を任意に調整可能
に構成している。In FIG. 5, reference numeral 1A is a probe equipped with a transmitting / receiving unit 1, 10 is a control circuit for the transmitting / receiving unit, and 11 is a measuring waveform from the receiving unit via the control circuit. In the received wave detection circuit, an S gate generation circuit 12 that generates an inhibition gate (S gate) for detecting the surface echo S inside the tube, and an inhibition gate (B gate) that detects the surface echo S outside the tube and noise N are removed A B gate generation circuit 13 and a timer circuit 14 are additionally provided. Reference numeral 15 measures the time t between the surface echo (S echo) and the external surface echo (B echo) based on the clock from the in-pipe timer circuit, and multiplies this by the sound velocity of the pipe material to measure the thickness. It is an arithmetic circuit for performing. 16 is a cathode ray tube or other display for displaying the above-mentioned measured waveforms and prohibited gates, 17
Is a controller. The B gate generation circuit 13 is configured to be able to arbitrarily adjust the threshold level and the threshold width of the multi-level prohibited gate of the B gate according to an instruction from the controller 17.
【００１１】次に図１及び図２に基づいて前記測定波形
及び禁止ゲートについて説明する。図１において、
（Ａ）は測定波形の発生状態を示し、該波形中、Ｔは送
信パルス、Ｓは管内表面エコー、Ｎはノイズ、Ｂは管外
表面エコーである。また、図１中の（Ｂ）は管内表面エ
コーＳ検出の禁止ゲート（Ｓゲート）、言換えれば時間
ｔ計測の原点を決めるための禁止ゲートを示し、前記し
たコントローラ１７の指示によりＳゲートの立上り時期
（ＳＴＡＲＴ）と高さレベル（Ｌ）を調整出来るように
なっており、ゲートの立上りから最も近い位置に現われ
たエコー、即ち管内表面エコーＳを時間計測の原点とし
て認識する。Next, the measurement waveform and the inhibition gate will be described with reference to FIGS. 1 and 2. In FIG.
(A) shows the generation state of the measured waveform, in which T is a transmission pulse, S is a surface echo inside the tube, N is noise, and B is an echo outside the tube. Further, (B) in FIG. 1 shows a prohibition gate (S gate) for detecting the surface echo S in the tube, in other words, a prohibition gate for determining the origin of the time t measurement. The rising timing (START) and the height level (L) can be adjusted, and the echo appearing at the closest position from the rising of the gate, that is, the pipe surface echo S is recognized as the origin of time measurement.
【００１２】即ち、管３の内側から水を媒体として管３
の厚さを測定する場合、時間計測の原点となるのはＳエ
コー（管内表面３ａエコー）であるので、Ｓゲートの立
上りはＳエコーより送信パルス（Ｔパルス）側に設定す
る必要があり、且つ高さレベルはノイズレベルより６〜
１２ｄｂ（デシベル）高目に設定する。That is, water is used as a medium from the inside of the pipe 3
When measuring the thickness of S, since the origin of time measurement is the S echo (echo inside the tube 3a), the rising edge of the S gate must be set to the transmission pulse (T pulse) side of the S echo. And the height level is 6 ~ than the noise level
Set to 12db (decibels) higher.
【００１３】一方、図１（Ｃ）に示すＢゲートは、Ｓエ
コーの後に最初に現われるエコー（管外表面３ｂからの
反射エコー（Ｂエコー））をとらえ、Ｓエコーからの距
離（時間）を計測するためにＢエコーを精度良く且つ確
実に検出するための禁止ゲートで、Ｓゲートと同様、Ｂ
ゲートの立上りから最も近い位置に現われたエコーをＢ
エコーとして取り込む様になっている。On the other hand, the B gate shown in FIG. 1 (C) captures the echo (reflection echo (B echo) reflected from the outer surface 3b) that appears first after the S echo, and determines the distance (time) from the S echo. Forbidden gate to detect B echo accurately and surely for measurement.
The echo that appears closest to the rising edge of the gate is B
It is designed to be captured as an echo.
【００１４】このＢゲートの特徴は、測定波形上のノイ
ズ部分にノイズの形状に合わせて、ゲートの立上り時期
（ＳＴＡＲＴ）と閾値高さレベル（Ｌ１，２，３・・・
ｎ）及び閾値幅（Ｗ１，２，３・・・ｎ）が、調整可能
な多段レベル状（例えば階段状や鋸歯状）の禁止ゲート
（Ｂゲート）を設けたことであり、この禁止ゲート内の
ノイズは時間計測の対象外として無視するようにした。
そして、各段の閾値高さレベル（Ｌ１，２，３・・・
ｎ）を越えたエコーについてのみ検出し、前記Ｓエコー
よりの時間を前記演算回路等で計測するようにした。The characteristic of the B gate is that the rise time (START) of the gate and the threshold height level (L1, 2, 3 ...
n) and the threshold width (W1, 2, 3, ... N) are provided with an adjustable multi-level level (for example, stepped or sawtooth) inhibition gate (B gate). The noise of is excluded from the target of time measurement.
Then, the threshold height level (L1, 2, 3, ...
Only echoes exceeding n) are detected, and the time from the S echo is measured by the arithmetic circuit or the like.
【００１５】図２は、前記Ｂゲートが５段式の禁止ゲー
トである超音波厚さ計のディスプレー１６上に表示され
た例示で、測定波形が図２の様なノイズ形状の場合、先
ず、Ｂゲートの２段目と４段目のゲートの閾値幅（Ｗ）
と閾値高さ（Ｌ）をノイズの形状に合わせて調整する。
そして、ノイズに関係のない１段目と３段目及び５段目
のゲートの閾値高さをディスプレー１６上基線近傍まで
出来るだけ下げた後、管外表面エコーＢの取り込み開始
点である１段目のゲートの立上り（ＢゲートのＳＴＡＲ
Ｔ）を、Ｓエコーの不感帯を避けてその直後に設定す
る。このような調整を行なえば、図２に斜線Ａで示す様
に基線Ｉの直上から管外表面３ｂエコーの取り込み範囲
となるので、超音波の反射エネルギーが極端に低下する
局部減肉部５でも、ノイズに関係なく管３の厚さ測定が
可能である。FIG. 2 shows an example displayed on the display 16 of the ultrasonic thickness gauge in which the B gate is a 5-step prohibition gate. In the case where the measurement waveform has a noise shape as shown in FIG. Threshold width (W) of the second and fourth gates of B gate
And the threshold height (L) are adjusted according to the noise shape.
Then, after lowering the threshold heights of the gates of the first stage, the third stage, and the fifth stage, which are not related to noise, to the vicinity of the base line on the display 16 as much as possible, the first stage, which is the starting point for capturing the external surface echo B Rise of eye gate (B gate STAR
T) is set immediately after avoiding the dead zone of S echo. If such an adjustment is made, as shown by the hatched line A in FIG. 2, the range from immediately above the baseline I to the echo surface 3b echo is captured, so that even in the local thinned portion 5 where the reflected energy of ultrasonic waves is extremely reduced. The thickness of the tube 3 can be measured regardless of noise.
【００１６】次に図６に基づいて、図５に基づく本実施
例の管厚さ測定手順について説明する。先ず送信パルス
（Ｔパルス）受波後（Ｓ１）、該送信パルスの不感帯を
避けてその直後に、Ｓゲートを立上げる。（Ｓ２） Ｓゲートを立上げ後に最初に現われるエコー（Ｓエコ
ー）を受波し、時間計測ｔを開始する。（Ｓ３） 次にＳエコー受波後、該Ｓエコーの不感帯を避けてその
直後に、Ｂゲートを立上げる。（Ｓ４） Ｂゲートは、測定波形上のノイズ部分にノイズの形状に
合わせて、ゲートの立上り時期と閾値高さレベル）及び
閾値幅を前もって調整しておく。Ｂゲートを立上げ後に
最初に現われるエコー（Ｂエコー）を受波し、該受波時
点で時間計測ｔを停止する。（Ｓ５） 前記計測した時間ｔを演算回路に取込み、該時間ｔと管
材の音速を乗ずることにより厚さの測定を行う。（Ｓ
６）Next, the tube thickness measuring procedure of this embodiment based on FIG. 5 will be described with reference to FIG. First, after receiving the transmission pulse (T pulse) (S1), the dead zone of the transmission pulse is avoided and immediately after that, the S gate is activated. (S2) The echo (S echo) that first appears after the S gate is activated is received, and the time measurement t is started. (S3) Next, after receiving the S echo, the dead zone of the S echo is avoided and immediately after that, the B gate is activated. (S4) In the B gate, the rising time of the gate and the threshold height level) and the threshold width are adjusted in advance according to the noise shape on the noise portion on the measurement waveform. The first echo (B echo) that appears after the B gate is activated is received, and the time measurement t is stopped at the time of the reception. (S5) The measured time t is taken into the arithmetic circuit, and the thickness is measured by multiplying the time t by the sound velocity of the pipe material. (S
6)
【００１７】[0017]
【発明の効果】以上記載のごとく本発明の超音波厚さ計
によれば、測定波形上のノイズ部分にノイズの形状に合
わせて、ゲートの立上りと閾値及び幅が、調整可能な多
段式の禁止ゲートを設け、この禁止ゲート内のノイズは
時間計測の対象外として無視するようにするとともに、
ノイズと関係のない残りのゲートは、ブラウン管の基線
近傍まで閾値を下げられる様にしているので、超音波の
反射エネルギーが極端に低下する局部減肉部５でも、ノ
イズに関係なく熱交換器の管等の厚さ測定が可能であ
る。As described above, according to the ultrasonic thickness gauge of the present invention, the rising edge of the gate and the threshold value and width can be adjusted according to the shape of the noise in the noise portion on the measured waveform. A forbidden gate is provided, and noise in this forbidden gate is ignored as not subject to time measurement.
The remaining gates not related to noise are designed so that the threshold value can be lowered to the vicinity of the base line of the cathode ray tube. Therefore, even in the local thinned portion 5 where the reflected energy of the ultrasonic wave is extremely reduced, the heat exchanger is not affected by noise. It is possible to measure the thickness of pipes.
【図１】本発明の禁止ゲート付超音波厚さ計のゲート機
構の説明図。FIG. 1 is an explanatory view of a gate mechanism of an ultrasonic thickness gauge with a prohibition gate according to the present invention.
【図２】本発明の禁止ゲート付超音波厚さ計のゲートの
調整要領図。FIG. 2 is a diagram of the adjustment procedure of the gate of the ultrasonic thickness gauge with a prohibited gate according to the present invention.
【図３】管の内側から超音波を利用して厚さを測定する
場合の原理図。FIG. 3 is a principle diagram in the case of measuring the thickness from the inside of the tube using ultrasonic waves.
【図４】従来型超音波厚さ計のオートゲイン機構の説明
図。FIG. 4 is an explanatory diagram of an auto gain mechanism of a conventional ultrasonic thickness gauge.
【図５】図１の禁止ゲートを生成するための超音波厚さ
計の要部回路ブロック図。5 is a circuit block diagram of a main part of an ultrasonic thickness gauge for generating the inhibition gate of FIG.
【図６】図５の回路の動作手順を示すフローチャート図
である。FIG. 6 is a flowchart showing an operation procedure of the circuit of FIG.
Ｔ 送信パルス Ｓ 管内表面エコー Ｂ 管外表面エコー ｔ 管の厚さに相当する時間 Ｎ ノイズ Ｌ 閾値高さ Ｗ 閾値幅 Ｓゲート、Ｂゲート 禁止ゲート T Transmit pulse S Surface echo inside tube B Surface echo outside tube t Time equivalent to tube thickness N Noise L Threshold height W Threshold width S gate, B gate Forbidden gate
Claims (1)
号を識別するために禁止ゲートを設けた超音波厚さ計で
あって、 前記測定波形のノイズ発生域に該ノイズの形状に合わせ
て、前記禁止ゲートの立上り位置、閾値高さ及び閾値幅
が、調整可能な多段レベル状の禁止ゲートを設け、この
禁止ゲート内のノイズ信号を無視して測定可能に構成す
るとともに、前記ノイズ発生域から外れた区域のゲート
閾値レベルを下げ、好ましくは測定波形画面上の基線近
傍まで閾値レベルを下げて前記多段レベル状の禁止ゲー
トを形成したことを特徴とする超音波厚さ計。1. An ultrasonic thickness gauge provided with a prohibition gate for distinguishing noise and received (echo) signal from a measured waveform, the ultrasonic thickness meter being adapted to a noise generation region of the measured waveform according to the shape of the noise. A rise gate, a threshold height and a threshold width of the prohibition gate are provided so that a multilevel level prohibition gate is provided, and the noise signal in the prohibition gate can be ignored for measurement, and the noise generation area An ultrasonic thickness gauge, characterized in that the gate threshold level of the area deviated from is lowered, and preferably the threshold level is lowered to near the base line on the measurement waveform screen to form the multi-step level forbidden gate.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP33434495A JP3453236B2 (en) | 1995-11-30 | 1995-11-30 | Ultrasonic thickness gauge with prohibition gate |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP33434495A JP3453236B2 (en) | 1995-11-30 | 1995-11-30 | Ultrasonic thickness gauge with prohibition gate |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH09152325A true JPH09152325A (en) | 1997-06-10 |
| JP3453236B2 JP3453236B2 (en) | 2003-10-06 |
Family
ID=18276321
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP33434495A Expired - Lifetime JP3453236B2 (en) | 1995-11-30 | 1995-11-30 | Ultrasonic thickness gauge with prohibition gate |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3453236B2 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006078371A (en) * | 2004-09-10 | 2006-03-23 | Keyence Corp | Ranging sensor and setting method therefor |
| JP2006078370A (en) * | 2004-09-10 | 2006-03-23 | Keyence Corp | Range sensor and its setting method |
-
1995
- 1995-11-30 JP JP33434495A patent/JP3453236B2/en not_active Expired - Lifetime
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006078371A (en) * | 2004-09-10 | 2006-03-23 | Keyence Corp | Ranging sensor and setting method therefor |
| JP2006078370A (en) * | 2004-09-10 | 2006-03-23 | Keyence Corp | Range sensor and its setting method |
Also Published As
| Publication number | Publication date |
|---|---|
| JP3453236B2 (en) | 2003-10-06 |
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