JP3249425B2 - Crack measuring device - Google Patents
Crack measuring deviceInfo
- Publication number
- JP3249425B2 JP3249425B2 JP11564097A JP11564097A JP3249425B2 JP 3249425 B2 JP3249425 B2 JP 3249425B2 JP 11564097 A JP11564097 A JP 11564097A JP 11564097 A JP11564097 A JP 11564097A JP 3249425 B2 JP3249425 B2 JP 3249425B2
- Authority
- JP
- Japan
- Prior art keywords
- crack
- measuring device
- contact needles
- subject
- contact
- 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
- Investigating Or Analyzing Materials By The Use Of Electric Means (AREA)
Description
【発明の詳細な説明】DETAILED DESCRIPTION OF THE INVENTION
【０００１】[0001]
【発明の属する技術分野】本発明は、鋼構造物、金属材
料の板厚及び表面部欠陥等の亀裂を非破壊で検査する亀
裂測定装置に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a crack measuring device for non-destructively inspecting cracks such as a thickness of a steel structure and a metal material and a surface defect.
【０００２】[0002]
【従来の技術】金属材料等の内部に亀裂がある場合、亀
裂を横切るように流れる電流は亀裂により妨げられ、そ
の亀裂付近の抵抗値は亀裂の深さに比例して増加する。
この亀裂の深さを測定するため、例えば図４に示す亀裂
測定装置が用いられている。2. Description of the Related Art When a crack is present inside a metal material or the like, a current flowing across the crack is hindered by the crack, and the resistance value near the crack increases in proportion to the depth of the crack.
In order to measure the depth of the crack, for example, a crack measuring device shown in FIG. 4 is used.
【０００３】図４（ａ）は従来の亀裂測定装置の検出部
を詳細に示した横断面図であり、図４（ｂ）は同検出部
を上面から見た図である。接触針１ａ〜１ｄは直線状の
ものであり、それぞれが一定間隔ａだけ離れて平行に設
けられている。また、接触針１ａ〜１ｄの根元部分には
それぞれコイルばね２が設けられているため、被検面に
押圧した際にコイルばね２が収縮することにより、被検
体８に凹凸面が存在しても４本の接触針１ａ〜１ｄが良
好に接触するようになっている。コイルばね２の上端に
は蓋４が設けられ、蓋４とケーシング３により検出部を
被包する。FIG. 4A is a cross-sectional view showing in detail a detecting section of a conventional crack measuring device, and FIG. 4B is a view of the detecting section as viewed from above. The contact needles 1a to 1d are linear, and are provided in parallel at a predetermined interval a. In addition, since the coil springs 2 are provided at the root portions of the contact needles 1a to 1d, the coil springs 2 contract when pressed against the surface to be inspected. Also, the four contact needles 1a to 1d come into good contact with each other. A cover 4 is provided at the upper end of the coil spring 2, and the detection unit is covered by the cover 4 and the casing 3.
【０００４】本発明の対象とする亀裂測定装置の測定動
作を図５に示す。被検体８の亀裂９を挟んで等間隔ａの
４本の接触針１ａ〜１ｄを亀裂に対して直角に当て、外
側の２本の接触針１ａ，１ｄにリード線５を通じて一定
の直流電流１０を流し、内側の２本の接触針１ｂ，１ｃ
に接続された計測装置６により電位差Ｖを測定する。FIG. 5 shows a measuring operation of the crack measuring apparatus to which the present invention is applied. Four contact needles 1a to 1d at equal intervals a are applied at right angles to the crack with the crack 9 of the subject 8 interposed therebetween, and a constant DC current 10 is passed through the lead wire 5 to the two outer contact needles 1a and 1d. And the inner two contact needles 1b, 1c
The potential difference V is measured by the measuring device 6 connected to the.
【０００５】また、測定した電位差Ｖ及び予め測定して
おいた亀裂９が存在しない健全部の測定電圧Ｖ0 より、
電圧比Ｖ／Ｖ0 を算出する。このＶ／Ｖ0 の値に基づ
き、図６に示す関係式からｄ／ａを求め、亀裂９の深さ
ｄを算出し、指示計７で表示する。このようにして亀裂
の深さを非破壊的に求めることができる。Further, based on the measured potential difference V and the previously measured voltage V 0 of the sound portion where no crack 9 is present,
The voltage ratio V / V 0 is calculated. Based on the value of V / V 0 , d / a is obtained from the relational expression shown in FIG. 6, and the depth d of the crack 9 is calculated and displayed on the indicator 7. In this way, the depth of the crack can be determined non-destructively.
【０００６】[0006]
【発明が解決しようとする課題】上記従来の亀裂測定装
置では、以下に示す問題点が生ずる。すなわち、金属体
等の内部における亀裂深さは一定でなく、大小さまざま
である。電気抵抗法による亀裂測定は、亀裂深さｄと各
接触針の間隔ａとは密接な関係があり、図６に示すよう
にｄ／ａ＜１の範囲では被検体厚さをｔとしたときのｔ
／ａの値いかんにかかわらず、Ｖ／Ｖ0 とｄ／ａは直線
関係にある。従って亀裂深さを正確に測定するために
は、直線関係にある範囲で測定する必要がある。The above-described conventional crack measuring device has the following problems. That is, the depth of cracks inside a metal body or the like is not constant, but varies in size. In the crack measurement by the electric resistance method, the crack depth d has a close relationship with the distance a between the contact needles, and when the thickness of the subject is t in the range of d / a <1, as shown in FIG. T
Regardless of the value of / a, V / V 0 and d / a have a linear relationship. Therefore, in order to accurately measure the crack depth, it is necessary to measure within a linear relationship.
【０００７】亀裂測定装置の検出部に設けた接触針１
は、上記したように一定間隔ａで固定されている。実際
に測定を行う場合においては、亀裂９は被検体８表面か
ら判別できないため、従来は接触針１ａ〜１ｄ間の間隔
ａが異なる亀裂測定装置を数種類用意し、亀裂に応じた
接触針の間隔を有する亀裂測定装置を選定して測定して
いた。[0007] Contact needle 1 provided in the detection section of the crack measuring device
Are fixed at a constant interval a as described above. In actual measurement, the crack 9 cannot be distinguished from the surface of the subject 8, and therefore, conventionally, several types of crack measuring devices having different distances a between the contact needles 1 a to 1 d are prepared, and the distance between the contact needles according to the crack is prepared. Was selected and measured.
【０００８】本発明は上記課題を解決するためになされ
たもので、その目的とするところは、亀裂深さが不明で
あっても複数の検出器を使用することなく、一の検出器
で亀裂の深さに対応した測定を可能とする亀裂測定装置
を提供することにある。SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to use a single detector for cracking without using a plurality of detectors even if the crack depth is unknown. It is an object of the present invention to provide a crack measuring device capable of performing a measurement corresponding to the depth of a crack.
【０００９】[0009]
【課題を解決するための手段】本発明の亀裂測定装置
は、被検体に電流を流したときに、この被検体表面の亀
裂を挟んだ２点間で発生する電圧を測定する亀裂測定装
置本体と、この亀裂測定装置本体で得られた測定電圧、
予め求めておいた健全時の電圧及び亀裂を挟んだ被検体
の２点間の距離に基づいて被検体の亀裂の深さを算出す
る計測部とを備えた亀裂測定装置において、前記亀裂測
定装置本体に回転可能に軸支持された２つの腕部材と、
この腕部材の回転軸とは異なる位置に取り付けられ、腕
部材とともに回転して被検体の亀裂を挟んで発生する電
圧を測定する２つの接触針と、前記２つの腕部材の回転
角を調整することにより該２つの接触針間の距離を変更
させる手段とを具備してなることを特徴とする。SUMMARY OF THE INVENTION A crack measuring device according to the present invention measures a voltage generated between two points sandwiching a crack on the surface of a subject when a current is applied to the subject. And the measured voltage obtained by this crack measuring device body,
A measuring unit for calculating a depth of the crack of the subject based on a previously determined healthy voltage and a distance between two points of the subject sandwiching the crack. Two arm members rotatably supported by the main body,
Two contact needles that are attached to a position different from the rotation axis of the arm member and rotate together with the arm member to measure a voltage generated across a crack in the subject, and adjust a rotation angle of the two arm members. Means for changing the distance between the two contact needles.
【００１０】本発明の望ましい形態を以下に示す。 （１）亀裂測定装置本体に回転可能に軸支持された４つ
の腕部材を具備する。 （２）上記４つの腕部材は、同一直線上に軸を有し、外
側の２つの腕部材には被検体に電流を流す２つの接触針
を腕部材の回転軸とは異なる位置に取り付け、内側の２
つの腕部材には被検体の亀裂を挟んで発生する電圧を測
定する２つの接触針を腕部材の回転軸とは異なる位置に
取り付ける。Preferred embodiments of the present invention will be described below. (1) Four arm members rotatably supported on the crack measuring device main body are provided. (2) The four arm members have axes on the same straight line, and two contact needles for passing a current to the subject are attached to the outer two arm members at positions different from the rotation axis of the arm members. Inside 2
Two contact needles for measuring a voltage generated across a crack of the subject are attached to one arm member at a position different from the rotation axis of the arm member.
【００１１】（３）上記（１）の４つの腕部材として、
各腕部材の回転軸と接触針間の距離が異なるものを用い
る。また、各腕部材は、腕部材の回転軸と接触針間の距
離が各接触針の位置する直線及び腕部材の回転軸の位置
する直線との交点から各接触針までの距離に比例するよ
うに配置する。(3) As the four arm members of the above (1),
A different distance between the rotation axis of each arm member and the contact needle is used. In each arm member, the distance between the rotation axis of the arm member and the contact needle is proportional to the distance from the intersection of the straight line where the contact needle is located and the straight line where the rotation axis of the arm member is located to each contact needle. To place.
【００１２】（４）上記（１）の４つの腕部材における
各腕部材が同一の回転角を保持しながら回転させること
により各接触針間の距離を等間隔に保持しながら変更さ
せる手段を備える。 （５）上記（１）の４つの腕部材のうちの外側の１つの
腕部材の代わりに、固定軸を設け、この固定軸に接触針
を取り付ける。(4) A means is provided for changing the distance between the contact needles while maintaining the same angle of rotation by rotating each of the four arm members of the above (1) while maintaining the same rotation angle. . (5) A fixed shaft is provided in place of the outer one of the four arm members (1), and a contact needle is attached to the fixed shaft.
【００１３】[0013]
【発明の実施の形態】以下、図面を参照しながら本発明
の一実施形態を説明する。図１は、本発明の一実施形態
に係る亀裂測定装置の全体構成を示す図、図２は、同装
置における支持体の断面図、図３は、同装置の作用図で
ある。図１，図２に示すように、本発明の亀裂測定装置
本体には３つの異なる大きさの絶縁性の支持体１１ａ〜
１１ｃが設けられている。これら支持体１１ａ〜１１ｃ
は楕円かつ筒状であり、その一端は上下に貫通し、貫通
した穴には導電性の軸１２ａ〜１２ｃが通じている。こ
の軸１２ａ〜１２ｃを中心軸として、支持体１１ａ〜１
１ｃは軸１２ａ〜１２ｃと一体となって回転可能なよう
になっている。これら軸１２ａ〜１２ｃに軸１２ｄを含
めた４つの軸１２ａ〜１２ｄは、それぞれ同一直線上に
等間隔で並んでいる。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing the overall configuration of a crack measuring device according to an embodiment of the present invention, FIG. 2 is a cross-sectional view of a support in the device, and FIG. 3 is an operation diagram of the device. As shown in FIGS. 1 and 2, three different sizes of insulating supports 11a to 11c are provided in the crack measuring device body of the present invention.
11c is provided. These supports 11a to 11c
Has an elliptical and cylindrical shape, one end of which penetrates vertically, and a conductive shaft 12a to 12c communicates with the penetrated hole. With these shafts 12a to 12c as central axes,
1c is rotatable integrally with the shafts 12a to 12c. Four shafts 12a to 12d including the shafts 12a to 12c including the shaft 12d are arranged at equal intervals on the same straight line.
【００１４】また、支持体１１ａ〜１１ｃには軸１２ａ
〜１２ｃが設けられた一端と長軸方向反対側に、軸１２
ａ〜１２ｃに平行して上下に貫通穴が設けられ、また軸
１２ｄの下部に設けられたケーシング３に貫通穴が設け
られている。これら貫通穴にはコイルばね２ａ〜２ｄが
挿入されており、これらコイルばね２ａ〜２ｄの先端に
は接触針１ａ〜１ｄが設けられている。コイルばね２ａ
〜２ｄは、測定時における接触針１ａ〜１ｄの被検面へ
の接触性を保持するためのものである。すなわち、接触
針１ａ〜１ｄの押圧に伴いコイルばね２ａ〜２ｄが収縮
することにより被検体８に凹凸面が存在しても各接触針
１ａ〜１ｄが上下方向に摺動して被検面に完全に接触す
るようになっている。The supports 11a to 11c have a shaft 12a.
12c is provided on the opposite side of one end provided with
Through holes are provided vertically above and below a to 12c, and a through hole is provided in the casing 3 provided below the shaft 12d. Coil springs 2a to 2d are inserted into these through holes, and contact needles 1a to 1d are provided at the tips of these coil springs 2a to 2d. Coil spring 2a
2 to 2d are for maintaining the contactability of the contact needles 1a to 1d to the surface to be measured at the time of measurement. That is, even if the test object 8 has an uneven surface due to the contraction of the coil springs 2a to 2d due to the pressing of the contact needles 1a to 1d, each of the contact needles 1a to 1d slides in the vertical direction, and It comes in complete contact.
【００１５】支持体１１ａ〜１１ｃの上面には軸１２ａ
〜１２ｄを保持する上部板１９が設けられている。支持
体１１ａ〜１１ｃとともに回転する軸１２ａ〜１２ｃ
は、ケーシング３の下部に設けられた突起１８に固定さ
れている。この突起１８は軸１２ａ〜１２ｃを支持し、
上部板１９とともに回転可能な凹部を設けている。A shaft 12a is provided on the upper surfaces of the supports 11a to 11c.
There is provided an upper plate 19 for holding .about.12d. Shafts 12a to 12c rotating together with supports 11a to 11c
Is fixed to a projection 18 provided at a lower portion of the casing 3. The projection 18 supports the shafts 12a to 12c,
A concave portion rotatable with the upper plate 19 is provided.
【００１６】支持体１１ａ〜１１ｃの上部には蓋１４が
取り付けられ、この蓋１４を貫通した穴からは軸１２ａ
〜１２ｄのみが突出しており、収縮自在のコイルばね２
ａ〜２ｃは突出しない構成となる。また、コイルばね２
ｄは、上部板１９によりコイルばね２ｄの突出を防ぐ構
成となる。軸１２ａ〜１２ｃの上端にはそれぞれ同径の
プーリー１５が固着されている。プーリー１５は、軸１
２ａ〜１２ｄと一体となって回転するようになってお
り、その外周には溝付ベルト１６が巻かれている。この
溝付ベルト１６により支持体１１ａ〜１１ｃがそれぞれ
連動して回転するようになっている。A cover 14 is attached to the upper portions of the supports 11a to 11c.
-12d protruding and contractible coil spring 2
a to 2c do not protrude. The coil spring 2
In the configuration d, the upper plate 19 prevents the coil spring 2d from projecting. Pulleys 15 having the same diameter are fixed to the upper ends of the shafts 12a to 12c, respectively. The pulley 15 is connected to the shaft 1
It rotates integrally with 2a to 12d, and a grooved belt 16 is wound around its outer periphery. The grooved belt 16 allows the supports 11a to 11c to rotate in conjunction with each other.
【００１７】さらに、支持体１１ａに対応するプーリー
１５には指針付ツマミ１７が固定されており、プーリー
１５，軸１２ａと一体となって回転するようになってい
る。すなわち、指針付ツマミ１７を回転させることによ
り接触針１ａ〜１ｃが同時かつ同じ角度を保持したまま
回転する。この指針付ツマミ１７には目盛り２０が設け
られ、この目盛り２０を読むことにより、各接触針１ａ
〜１ｄ間の距離が分かるようになっている。Further, a knob 17 with a pointer is fixed to the pulley 15 corresponding to the support 11a, and is rotated integrally with the pulley 15 and the shaft 12a. That is, by rotating the knob 17 with the pointer, the contact needles 1a to 1c rotate simultaneously and while maintaining the same angle. The scale 17 is provided with a scale 20. By reading the scale 20, each contact needle 1a is read.
The distance between 〜1d can be understood.
【００１８】接触針１ａ〜１ｄはそれぞれ導電性の材料
で構成される。これら接触針１ａ〜１ｄ及び軸１２ａ〜
１２ｄ間はそれぞれリード線５で電気的に接続されてお
り、両者が導通するようになっている。４本の接触針の
うち１ａ及び１ｄは図示しない電圧源を挟んで軸１２を
介して接続されており、１ｂ及び１ｃは軸１２を介して
計測装置６に接続されている。被検体に接触針１ａ〜１
ｄを接触させ、接触針１ａ及び１ｄ間に電圧を印加した
際に、この印加電圧により被検体中に生じた電流を接触
針１ｂ及び１ｃにより検出するような構成となってい
る。さらに、計測装置６に入力され、増幅及び信号処理
された検出信号は指示計７に出力され、被検体の亀裂深
さが表示される。Each of the contact needles 1a to 1d is made of a conductive material. These contact needles 1a-1d and shafts 12a-
The leads 12d are electrically connected to each other by the lead wire 5, so that both are conductive. Of the four contact needles, 1a and 1d are connected via a shaft 12 via a voltage source (not shown), and 1b and 1c are connected to the measuring device 6 via the shaft 12. Contact needles 1a to 1
d is brought into contact, and when a voltage is applied between the contact needles 1a and 1d, a current generated in the subject by the applied voltage is detected by the contact needles 1b and 1c. Further, the detection signal input to the measuring device 6 and amplified and signal-processed is output to the indicator 7, and the crack depth of the subject is displayed.
【００１９】なお、本亀裂測定装置の検出部は、カバー
１３で被包されている。上記実施形態に係る亀裂測定装
置の動作を説明する。まず、接触針１ａ〜１ｄを被検体
８に接触させる。接触の際には、接触針１ａ〜１ｄを被
検体８に対する押圧に伴いコイルばね２ａ〜２ｄが収縮
する。次に、図５に示すように接触針１ｂ及び１ｃ間に
亀裂９を挟み、接触針１ａ，１ｄ間に計測装置６から直
流電流１０を流す。亀裂９は接触針１ｂ，１ｃ間の被検
体８内部で抵抗として作用するため、亀裂深さｄに対応
した電位差が接触針１ｂ，１ｃ間に生じる。この電位差
は計測装置６で検出され、増幅及び信号処理される。そ
して、亀裂深さｄを表す信号として指示計７に出力さ
れ、指示計７で表示される。The detecting section of the crack measuring apparatus is covered with a cover 13. The operation of the crack measuring device according to the above embodiment will be described. First, the contact needles 1 a to 1 d are brought into contact with the subject 8. At the time of contact, the coil springs 2a to 2d contract as the contact needles 1a to 1d are pressed against the subject 8. Next, as shown in FIG. 5, a crack 9 is sandwiched between the contact needles 1b and 1c, and a direct current 10 is passed from the measuring device 6 between the contact needles 1a and 1d. Since the crack 9 acts as a resistance inside the subject 8 between the contact needles 1b and 1c, a potential difference corresponding to the crack depth d is generated between the contact needles 1b and 1c. This potential difference is detected by the measuring device 6, amplified and signal-processed. Then, the signal is output to the indicator 7 as a signal indicating the crack depth d, and is displayed on the indicator 7.
【００２０】上記した亀裂測定における電圧比と接触針
間の間隔ａ及び亀裂深さｄとの関係を図６に示す。図６
において、Ｖは測定電圧、Ｖ0 は亀裂９が存在しない健
全部において予め測定しておいた電圧を示す。電圧比Ｖ
／Ｖ0 を算出し、このＶ／Ｖ0 値に基づき、図６の関係
式からｄ／ａを求め、亀裂９の深さｄを推定する。この
ようにして亀裂の深さを非破壊的に求めることができ
る。本亀裂測定装置における測定では、亀裂深さｄと接
触針５１の間隔ａとは密接な関係があり、図６に示すよ
うにｄ／ａ＜１の範囲では被検体厚さをｔとしたときの
ｔ／ａの値いかんにかかわらず、Ｖ／Ｖ0 とｄ／ａは直
線関係にある。従って亀裂深さを正確に測定するために
はこの範囲で測定する必要がある。FIG. 6 shows the relationship between the voltage ratio and the distance a between the contact needles and the crack depth d in the crack measurement described above. FIG.
In the equation, V indicates a measured voltage, and V 0 indicates a voltage measured in advance in a sound portion where no crack 9 exists. Voltage ratio V
/ V 0 , and based on the V / V 0 value, d / a is obtained from the relational expression of FIG. 6 to estimate the depth d of the crack 9. In this way, the depth of the crack can be determined non-destructively. In the measurement by the present crack measuring device, the crack depth d and the distance a between the contact needles 51 have a close relationship, and when the thickness of the subject is t in the range of d / a <1, as shown in FIG. Regardless of the value of t / a, V / V 0 and d / a have a linear relationship. Therefore, it is necessary to measure within this range in order to accurately measure the crack depth.
【００２１】実際に測定を行う場合においては、被検体
８内の亀裂９は表面から判別できないため、指針付ツマ
ミ１７を回転させることにより接触針間の距離を変え、
上記図６の直線関係にある部分に合わせて測定を行う。When the measurement is actually performed, the distance between the contact needles is changed by rotating the knob 17 with a pointer since the crack 9 in the subject 8 cannot be distinguished from the surface.
The measurement is performed in accordance with the linear relationship shown in FIG.
【００２２】上記指示計７の表示を読みとる際、例えば
出力電圧が小さく指示計７の指示が不安定な場合は亀裂
深さｄに対し接触針１の間隔ａが大きいためで、指針付
ツマミ１７を左に回転させ、亀裂深さｄに対応した間隔
ａにする。また、出力電圧が大きすぎて不安定な場合は
指針付ツマミ１７を逆に回転させ間隔ａを大きくし、適
切な出力電圧を得る。When reading the display of the indicator 7, for example, when the output voltage is small and the indication of the indicator 7 is unstable, the interval a between the contact needles 1 is larger than the crack depth d. Is rotated to the left to make an interval a corresponding to the crack depth d. If the output voltage is too high and unstable, the knob 17 with the pointer is rotated in the reverse direction to increase the interval a to obtain an appropriate output voltage.
【００２３】図３を用いて指針付ツマミ１７の回転動作
に伴う支持体１１ａ〜１１ｃの作用を説明する。支持体
１１ａ〜１１ｃは、軸１２ａ〜１２ｃを中心軸として回
転する。接触針１ａ〜１ｃは、それぞれ軸１２ａ〜１２
ｃとの距離に比例した円弧を描いて回転する。また、接
触針１ａ〜１ｃと軸１２ａ〜１２ｃとの距離ｒa ，ｒ
b ，ｒc の関係は、ｒa ＝３ｒc ，ｒb ＝２ｒc となっ
ている。支持体１１ａ〜１１ｃの楕円断面の長軸がそれ
ぞれ一の直線上に位置するときには、各支持体間の距離
は全てａ3 となり、等間隔を保っている。ここで、指針
付ツマミ１７を回転させるとその回転動作に連動してプ
ーリー１５及び溝付ベルト１６が回転し、支持体１１ａ
〜１１ｃは、それぞれ楕円断面の長軸が平行な状態を保
持したまま同じ角度で回転する。従って、この回転動作
の後においても、距離ｒa ，ｒb ，ｒc の関係より、各
接触針間の距離は等間隔を保持したままａ3 からａ1 ま
で短くなる。このように、指針付ツマミ１７を回転させ
て接触針１ａ〜１ｄの間隔ａを自由に変えることができ
るとともに、その値を目盛り２０で読みとることができ
る。Referring to FIG. 3, the operation of the supports 11a to 11c associated with the rotating movement of the pointer 17 will be described. The supports 11a to 11c rotate around the axes 12a to 12c. The contact needles 1a to 1c are respectively provided with shafts 12a to 12c.
Rotate in an arc proportional to the distance to c. Further, the distances r a and r between the contact needles 1 a to 1 c and the shafts 12 a to 12 c
b, the relationship of r c is, r a = 3r c, and has a r b = 2r c. When the major axis of the ellipse cross section of the support 11a~11c is positioned on one straight line respectively, becomes the distance all a 3 between the supports, it is kept equidistant. Here, when the knob 17 with the pointer is rotated, the pulley 15 and the grooved belt 16 are rotated in conjunction with the rotation thereof, and the support 11a is rotated.
11c rotate at the same angle while maintaining the state in which the major axes of the elliptical cross sections are parallel. Thus, even after the rotation, the distance r a, r b, the relationship of r c, the distance between the contact needles are shorter from left a 3 holding the regular intervals until a 1. As described above, the distance a between the contact needles 1a to 1d can be freely changed by rotating the knob 17 with a pointer, and the value can be read on the scale 20.
【００２４】このように、接触針１ａ〜１ｃを回転可能
な支持体１１ａ〜１１ｃに取り付けることにより、各接
触針間の距離を等間隔に保持したまま変えることができ
る。従って、亀裂深さｄを測定する際に、ｄの大きさに
関係なく一の検出器で正確に測定することができ、作業
効率が向上するとともに経済的である。As described above, by attaching the contact needles 1a to 1c to the rotatable supports 11a to 11c, the distance between the contact needles can be changed while maintaining them at equal intervals. Therefore, when measuring the crack depth d, it is possible to accurately measure the crack depth irrespective of the size of d with one detector, thereby improving the working efficiency and economical.
【００２５】[0025]
【発明の効果】以上説明したように本発明によれば、亀
裂測定装置本体に回転可能に軸支持され、前記２つの接
触針を回転可能なように取り付けた２つの腕部材と、こ
の２つの腕部材の回転軸とは異なる位置に取り付けら
れ、腕部材とともに回転して被検体の亀裂を挟んで発生
する電圧を測定する２つの接触針と、前記２つの腕部材
の回転角を調整することにより該２つの接触針間の距離
を変更させる手段とっを具備してなるため、接触針の間
隔を自由に設定できる。したがって、一の検出器で亀裂
の深さに対応した測定が可能となるので作業効率が向上
するとともに経済的である。As described above, according to the present invention, two arm members rotatably supported by the crack measuring device main body and rotatably mounted with the two contact needles are provided. Two contact needles attached to a position different from the rotation axis of the arm member and rotating together with the arm member to measure a voltage generated across a crack in the subject; and adjusting a rotation angle of the two arm members. Thus, the distance between the two contact needles is changed, so that the distance between the contact needles can be set freely. Therefore, the measurement corresponding to the depth of the crack can be performed with one detector, so that the working efficiency is improved and it is economical.
【図１】本発明の一実施形態に係る亀裂測定装置の全体
構成を示す図。FIG. 1 is a diagram showing an entire configuration of a crack measuring device according to an embodiment of the present invention.
【図２】同実施形態における支持体の断面図。FIG. 2 is a cross-sectional view of the support in the embodiment.
【図３】同実施形態における亀裂測定装置の作用図。FIG. 3 is an operation diagram of the crack measuring device in the embodiment.
【図４】従来の亀裂測定装置の検出部を示す図。FIG. 4 is a diagram showing a detection unit of a conventional crack measuring device.
【図５】本発明の対象となる亀裂測定装置の回路構成を
示す図。FIG. 5 is a diagram showing a circuit configuration of a crack measuring device according to the present invention.
【図６】本発明の対象となる亀裂測定装置の電圧比Ｖ／
Ｖ0 と間隔ａ及び亀裂深さｄの関係を示す図。FIG. 6 shows a voltage ratio V / of a crack measuring device to which the present invention is applied.
Diagram showing the relationship between V 0 and spacing a and the crack depth d.
１ａ〜１ｄ 接触針 ２ コイルばね ３ ケーシング ４ 蓋 ５ リード線 ６ 計測装置 ７ 指示計 ８ 被検体 ９ 亀裂 １０ 直流電流 １１ａ〜１１ｄ 支持体 １２ａ〜１２ｄ 軸 １３ カバー １５ プーリー １６ 溝付ベルト １７ 指針付ツマミ １８ 突起 １９ 上部板 ２０ 目盛り 1a-1d Contact needle 2 Coil spring 3 Casing 4 Lid 5 Lead wire 6 Measuring device 7 Indicator 8 Subject 9 Crack 10 DC current 11a-11d Support 12a-12d Shaft 13 Cover 15 Pulley 16 Slotted belt 17 Pointer knob 18 Projection 19 Upper plate 20 Scale
───────────────────────────────────────────────────── フロントページの続き (72)発明者 村川 寿 兵庫県高砂市荒井町新浜二丁目８番19号 高菱エンジニアリング株式会社内 (56)参考文献 特開 平３−84446（ＪＰ，Ａ) 実開 平３−4261（ＪＰ，Ｕ) 実開 昭61−67556（ＪＰ，Ｕ) (58)調査した分野(Int.Cl.7，ＤＢ名) G01N 27/00 - 27/24 ＪＩＣＳＴファイル（ＪＯＩＳ)──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hisashi Murakawa 2-8-19 Shinhama, Arai-machi, Takasago-shi, Hyogo Takahashi Engineering Co., Ltd. (56) References JP-A-3-84446 (JP, A) Hei 3-4261 (JP, U) Actually open Sho 61-67556 (JP, U) (58) Fields investigated (Int. Cl. 7 , DB name) G01N 27/00-27/24 JICST file (JOIS)
Claims (1)
体表面の亀裂を挟んだ２点間で発生する電圧を測定する
亀裂測定装置本体と、この亀裂測定装置本体で得られた
測定電圧、予め求めておいた健全時の電圧及び亀裂を挟
んだ被検体の２点間の距離に基づいて被検体の亀裂の深
さを算出する計測部とを備えた亀裂測定装置において、 前記亀裂測定装置本体に回転可能に軸支持された２つの
腕部材と、この腕部材の回転軸とは異なる位置に取り付
けられ、腕部材とともに回転して被検体の亀裂を挟んで
発生する電圧を測定する２つの接触針と、前記２つの腕
部材の回転角を調整することにより該２つの接触針間の
距離を変更させる手段とを具備してなることを特徴とす
る亀裂測定装置。1. A crack measuring device main body for measuring a voltage generated between two points sandwiching a crack on the surface of a subject when a current is applied to the subject, and a measurement obtained by the crack measuring device main body. A measuring unit for calculating a depth of a crack of the subject based on a voltage, a predetermined voltage in a healthy state, and a distance between two points of the subject sandwiching the crack. Two arm members rotatably supported by the measuring device main body and attached to a position different from the rotation axis of the arm members, and measure the voltage generated by rotating with the arm members and sandwiching the crack of the subject. A crack measuring device, comprising: two contact needles; and means for changing a distance between the two contact needles by adjusting a rotation angle of the two arm members.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP11564097A JP3249425B2 (en) | 1997-05-06 | 1997-05-06 | Crack measuring device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP11564097A JP3249425B2 (en) | 1997-05-06 | 1997-05-06 | Crack measuring device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH10307117A JPH10307117A (en) | 1998-11-17 |
| JP3249425B2 true JP3249425B2 (en) | 2002-01-21 |
Family
ID=14667654
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP11564097A Expired - Fee Related JP3249425B2 (en) | 1997-05-06 | 1997-05-06 | Crack measuring device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3249425B2 (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4789502B2 (en) * | 2005-04-26 | 2011-10-12 | 東京電力株式会社 | Crack depth measurement technique and apparatus for deep cracks using potentiometric method |
| JP2008128816A (en) * | 2006-11-21 | 2008-06-05 | Tohoku Univ | Non-destructive inspection device by potential difference method, and measurement method of non-destructive inspection using it |
| CN101963591B (en) * | 2010-08-13 | 2013-01-16 | 上海市建筑科学研究院(集团)有限公司 | Detection and evaluation method of crack condition on external insulating layer of thin-plastered outer wall |
| CN106527314B (en) * | 2015-10-25 | 2018-01-12 | 福州睿创纺织科技有限公司 | A kind of system monitored in real time on mobile phone |
| CN109765271B (en) * | 2018-12-30 | 2021-09-07 | 河海大学 | Device and method for judging hammering closing of metal fatigue crack |
-
1997
- 1997-05-06 JP JP11564097A patent/JP3249425B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH10307117A (en) | 1998-11-17 |
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