JPH01288701A - Elongation measurement - Google Patents
Elongation measurementInfo
- Publication number
- JPH01288701A JPH01288701A JP11967788A JP11967788A JPH01288701A JP H01288701 A JPH01288701 A JP H01288701A JP 11967788 A JP11967788 A JP 11967788A JP 11967788 A JP11967788 A JP 11967788A JP H01288701 A JPH01288701 A JP H01288701A
- Authority
- JP
- Japan
- Prior art keywords
- sample
- elongation
- reflector
- probe
- tip
- 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.)
- Granted
Links
- 238000005259 measurement Methods 0.000 title abstract description 10
- 239000000523 sample Substances 0.000 claims abstract description 60
- 230000008602 contraction Effects 0.000 claims description 6
- 238000001514 detection method Methods 0.000 abstract description 6
- 238000010276 construction Methods 0.000 abstract 1
- 239000000463 material Substances 0.000 description 7
- 238000000034 method Methods 0.000 description 7
- 238000010586 diagram Methods 0.000 description 5
- 238000009429 electrical wiring Methods 0.000 description 4
- 239000011888 foil Substances 0.000 description 3
- 239000002184 metal Substances 0.000 description 3
- 239000007779 soft material Substances 0.000 description 3
- 230000003287 optical effect Effects 0.000 description 2
- 238000009864 tensile test Methods 0.000 description 2
- 230000003321 amplification Effects 0.000 description 1
- 210000003484 anatomy Anatomy 0.000 description 1
- 239000000470 constituent Substances 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 238000000691 measurement method Methods 0.000 description 1
- 238000003199 nucleic acid amplification method Methods 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は、引張り試験における試験片の伸びを測定する
方法に関し、特に数％程度の伸びを測定するのに適した
伸び測定方法に関するものである。[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for measuring the elongation of a test piece in a tensile test, and particularly to an elongation measuring method suitable for measuring an elongation of about several percent. be.
構造物及び構成体の強度等を知るため、あるいは保守管
理等のために、構造材料の伸びを検知する必要が生じる
のは周知の事実である。このような伸びを測定する従来
の方法及び手段としては、−殻内に電気的に検知する方
法が用いられ、その手段としては、差動トランス式伸び
計、πゲージ式伸び計、歪ゲージ等が用いられている。It is a well-known fact that it is necessary to detect the elongation of structural materials in order to know the strength of structures and constituent bodies, or for maintenance management and the like. Conventional methods and means for measuring such elongation include - In-shell electrical sensing methods, such as differential transformer extensometers, π gauge extensometers, strain gauges, etc. is used.
（発明が解決しようとする課題）
しかしながら、上記両伸び計は、重量が一般的に数百グ
ラムもあり、柔かい材料に対して適用しようとした場合
、該重量が問題となり適用しえないものであった。また
紙あるいはプラスチック基材上に金属箔を固着せしめた
歪ゲージと呼ばれるものは軽量であるが、基材の弾性率
と金属箔の弾性率に違いがある場合には、基材が伸縮し
ても金属箔が基材の伸縮に追随しないという問題があっ
た。(Problem to be Solved by the Invention) However, both of the above extensometers generally weigh several hundred grams, and if they are to be applied to soft materials, the weight becomes a problem and they cannot be applied. there were. Strain gauges, which are made by fixing metal foil onto a paper or plastic base material, are lightweight, but if there is a difference in the elastic modulus of the base material and that of the metal foil, the base material may expand or contract. However, there was a problem in that the metal foil did not follow the expansion and contraction of the base material.
また伸縮量を電気的な変化層として検出する方法であれ
ば、必ず試料に取付けられる測定器に伸びを検出するた
めの電気的な配線を行わなければならず、また変化量を
増幅３を経て増幅しなければならないため、配線作業や
増幅器の取扱い上、測定が煩雑にならざるを得なかった
。In addition, if the amount of expansion and contraction is detected as an electrical change layer, it is necessary to install electrical wiring to the measuring device attached to the sample to detect the expansion, and the amount of change must be measured through amplification 3. Since it has to be amplified, measurements have become complicated due to wiring work and handling of the amplifier.
そこで本発明は、命中な構成で、（２かも合易じ伸び測
定を行うことができる伸び測定方法を提供することを目
的としている。Therefore, an object of the present invention is to provide an elongation measurement method that can perform elongation measurement with a precise configuration.
（課題を解決するための手段〕
上記目的を達成するために、本発明（ｉ、保持部材の−
・端部に固定された固定触針の先端を試料の表面Ｃ当接
させて試料に固定１−ろとともに、前記保持部材の他端
部に回動可能に設けられた回動触針の先端を、試料の表
面に試料の伸縮に対して追随可能に当接させ、該回動触
？１と一体的に設けられた反射機の回動角度を光学的に
測定することを特徴としている。(Means for Solving the Problems) In order to achieve the above object, the present invention (i.
- The tip of a fixed stylus fixed to the end is fixed to the sample by bringing it into contact with the surface C of the sample, and the tip of a rotating stylus rotatably provided at the other end of the holding member. is brought into contact with the surface of the sample so that it can follow the expansion and contraction of the sample, and the rotating contact ? It is characterized by optically measuring the rotation angle of a reflector provided integrally with 1.
以下本発明を図面に基づいて詳細に説明する。 The present invention will be explained in detail below based on the drawings.
第１図は本発明の伸び測定方法の測定原理を説明するも
ので、第２図は本発明の測定方法を実施するための測定
器の一実施例を示すもの、第３図は検出手段の一実施例
を示す説明図、第４図は検出手段の他の実施例を示す説
明図である。Fig. 1 explains the measurement principle of the elongation measuring method of the present invention, Fig. 2 shows an embodiment of a measuring device for carrying out the measuring method of the present invention, and Fig. 3 shows the detection means. FIG. 4 is an explanatory diagram showing one embodiment, and FIG. 4 is an explanatory diagram showing another embodiment of the detection means.
まず第１図において、試料Ｓの伸びを測定するには、保
持部材１の一解剖に固定された固定曽針？の先端２ａを
試料Ｓの表面に当接させて固定する。一方、前記保持部
材１の他端部に、試料Ｓの伸び方向Ｘと直交する方向に
設けられた回動支軸３により回動可能に設けられた回動
触針４の先端を、該回動触針４の先端４ａが試料Ｓの伸
縮に追随して移動し、前記回動支軸３を中心として回動
するように前記試料Ｓの表面に当接させる。First, in FIG. 1, in order to measure the elongation of the sample S, a fixed needle is fixed to an anatomical part of the holding member 1. The tip 2a of the sample S is brought into contact with the surface of the sample S and fixed. On the other hand, the tip of a rotating stylus 4, which is rotatably provided at the other end of the holding member 1 by a rotating shaft 3 provided in a direction perpendicular to the stretching direction X of the sample S, is attached to the other end of the holding member 1. The tip 4a of the movable contact needle 4 moves following the expansion and contraction of the sample S, and is brought into contact with the surface of the sample S so as to rotate about the pivot shaft 3.
そして試料Ｓを所定の引張力で引張り、前記回動触尖１
４と一体的に設けられた反射板５の回動角度θを光学的
に測定する。この反射板５の回動角度θの測定は、図示
のごとく、凸レンズ６と焦点板７を設けることにより、
容易に測定することができる。即ち、測定開始時に、反
射板５に向けて照射され、該反射板５で反射した光Ｒが
焦点板７の所定位置、例えば焦点板７の中心７ａで合焦
するように反射板５の角度及び凸レンズ６の位置を設定
しておく。Then, the sample S is pulled with a predetermined tensile force, and the rotating tactile tip 1 is
The rotation angle θ of the reflection plate 5 provided integrally with the reflection plate 4 is optically measured. The rotation angle θ of the reflection plate 5 can be measured by providing a convex lens 6 and a focusing plate 7 as shown in the figure.
Can be easily measured. That is, at the start of measurement, the angle of the reflector 5 is adjusted so that the light R irradiated toward the reflector 5 and reflected by the reflector 5 is focused at a predetermined position of the focus plate 7, for example, the center 7a of the focus plate 7. and the position of the convex lens 6.
これにより、試料Ｓの伸びに追随して回動触針４が回動
し、該回動触針４に設けられた反射板５が回動すると、
該反射板５で反射する光Ｒの焦点板７上での合焦像１１
Ｐが移動する。この移動距離を検出することにより、反
射板５の回動角度θが求められ、該反射板５の回動角度
θにより、回動触針４の先端４ａの移動距離（固定触針
２との相対的な移動距離）、即ち試料Ｓの伸びΔＬを測
定することができる。As a result, the rotary stylus 4 rotates following the elongation of the sample S, and when the reflection plate 5 provided on the rotary stylus 4 rotates,
A focused image 11 on the focusing plate 7 of the light R reflected by the reflecting plate 5
P moves. By detecting this movement distance, the rotation angle θ of the reflection plate 5 is determined, and from the rotation angle θ of the reflection plate 5, the movement distance of the tip 4a of the rotary stylus 4 (the distance between the tip 4a and the fixed stylus 2) is determined. relative movement distance), that is, the elongation ΔL of the sample S can be measured.
例えば、第１図の状態で、試料の標線間の距離、即ち固
定触針２の先端２ａと初期設定時の回動触針４の先端４
ａとの闇の距離をし、試料の伸びをΔＬ１両触針２．４
の長さ、即ち回動触針４の回動支軸３中心と先端４ａと
の距離をｄ３反射板５の回動角度をθ、凸レンズ６の焦
点距離をｆ、焦点板７における合焦位置Ｐの移動距離を
ｈとすると、次式により試料の伸びΔし及び伸び率εを
求めることができる。For example, in the state shown in FIG.
Determine the dark distance from
The length of the rotary stylus 4, that is, the distance between the center of the pivot shaft 3 and the tip 4a, is d, the rotation angle of the reflector 5 is θ, the focal length of the convex lens 6 is f, and the focusing position on the focus plate 7 is When the moving distance of P is h, the elongation Δ and the elongation rate ε of the sample can be determined by the following equations.
ｔａｎ（２θ）−ｈ／ｒ
、°、θ＝ （ｔａｎ” （ｈ／ｆ ） ） ／２ΔＬ
＝ ｄ ｘ ｔａｎθ
ε＝（Ｌ十ΔＬ）／Ｌ
ここで両触針の長さｄと焦点距離をｆは一定の値である
から、試料の伸びΔＬは合焦位置Ｐの移動距離りの同数
として求めることができる。また焦点板７に合焦像ｉ１
Ｐの移動距１ｈに対応する試料の伸びΔＬを示す目盛を
付しておけば、合焦位置Ｐの移動により、試料の伸びΔ
Ｌを直読することも可能である。従って、電気的な増幅
器等を必要とせず、電気的な配線や増幅器の操作等を行
う必要がないので、伸び測定の操作性を向上させること
ができる。tan(2θ)−h/r,°,θ=(tan”(h/f))/2ΔL
= d x tanθ ε = (L + ΔL)/L Here, since the length d of both stylus needles and the focal length f are constant values, the elongation ΔL of the sample is the same number as the distance traveled by the focus position P. It can be found as In addition, the focused image i1 on the focusing plate 7
If a scale is attached to indicate the elongation ΔL of the sample corresponding to the moving distance 1h of P, the elongation ΔL of the sample will be increased by moving the focus position P.
It is also possible to read L directly. Therefore, there is no need for an electrical amplifier or the like, and there is no need for electrical wiring or operation of the amplifier, so that the operability of elongation measurement can be improved.
次に第２図は、本発明の測定方法を実施するだめの測定
器の一実施例を示すものである。この測定器１０は、固
定触針部１１と回動触針部１２とを所定の良さの保持部
材１の両端に設けたもので、各部の大きさ等は、例えば
ＪＩＳ Ｋ ７１１３に規定されている引張り試験
片の形状に対応して形成される。Next, FIG. 2 shows an embodiment of a measuring device for carrying out the measuring method of the present invention. This measuring device 10 has a fixed stylus portion 11 and a rotary stylus portion 12 at both ends of a holding member 1 having a predetermined thickness, and the size of each portion is determined by, for example, JIS K 7113. It is formed to correspond to the shape of the tensile test piece.
上記固定触針部１１は、前記保持部＄４１と一体的に形
成された固定触針２と、該固定触針２、即ち測定器１０
を試料Ｓに固定するための固定具１３とで構成されてい
る。測定器１０を試料Ｓに固定するには、固定触！１２
の先端部両側に突設された角＠１４を固定具１３の両脚
片１５の開口１５ａに係止させ、固定触針２の対向側か
らスプリング１６の付勢力あるいはねじ１７等で固定板
１８を試料Ｓの裏面に押付けて、固定触針２と固定板１
８とで試料Ｓを挟着する。この時、固定触側２先端２ａ
のナイフェツジ部を、試料Ｓの横断方向、即ち試料Ｓの
伸び方向Ｘに直交する方向とする。The fixed stylus portion 11 includes a fixed stylus 2 integrally formed with the holding portion $41, and a measuring instrument 10.
and a fixture 13 for fixing the sample S to the sample S. To fix the measuring instrument 10 to the sample S, use the fixing touch! 12
The corners @ 14 protruding from both sides of the tip of the fixture 13 are engaged with the openings 15a of both leg pieces 15 of the fixture 13, and the fixing plate 18 is fixed from the opposite side of the fixed stylus 2 using the biasing force of the spring 16 or the screw 17. Press the fixed stylus 2 and the fixed plate 1 onto the back surface of the sample S.
Sample S is sandwiched between 8 and 8. At this time, the fixed contact side 2 tip 2a
The knife edge portion is defined as the transverse direction of the sample S, that is, the direction perpendicular to the elongation direction X of the sample S.
一方回動触釘部１２は、回動触針４が一体に形成された
反射板５を、回動支軸３により保持部材１の端部に形成
した腕部１９に回動可能に取付けている。この回動触針
４の先端４ａは、測定器１０を上記のごとく試料Ｓに固
定した状態で、試料Ｓの表面に適当な圧力で当接すｚｌ
ように形成されており、試料Ｓの伸縮に追随しＣ回動触
針４２反側根５を回動させる。On the other hand, the rotary pin part 12 has a reflection plate 5 integrally formed with the rotary pin 4 rotatably attached to an arm part 19 formed at the end of the holding member 1 by the rotary support shaft 3. There is. The tip 4a of the rotating stylus 4 is brought into contact with the surface of the sample S with an appropriate pressure while the measuring device 10 is fixed to the sample S as described above.
The C rotating contact needle 42 rotates the opposite root 5 following the expansion and contraction of the sample S.
第３図は、上記のごとく形成された測定器１０を用いた
際の、反射板５の回動角度を検出する手＆を示す一実施
例である。FIG. 3 shows an example of how to detect the rotation angle of the reflecting plate 5 when using the measuring instrument 10 formed as described above.
回動角度検出装置２０は、オー１へフリメータ２１ど、
これを支持するスタンド２２、及びオートコリメータ２
１の光軸Ｏを測定器１０の反射板５の向きに対応させる
ための反射鏡あるいはプリズム２３とで構成されている
。上記スタンド２２には、オートコリメータ２１の光軸
Ｏを反射板５の中心に合せるための粗調整部２２ａと微
調整部２２ｂが設けられている。The rotation angle detection device 20 includes a 1 to 1 frimeter 21, etc.
A stand 22 that supports this and an autocollimator 2
The measuring device 10 includes a reflecting mirror or prism 23 for making the optical axis O of the measuring device 1 correspond to the direction of the reflecting plate 5 of the measuring device 10. The stand 22 is provided with a coarse adjustment section 22a and a fine adjustment section 22b for aligning the optical axis O of the autocollimator 21 with the center of the reflection plate 5.
このように、上記第２図に示すような測定器１０とオー
トコリメータ２１を用いることにより、容易に試料Ｓの
伸び寸法を求めることができる。In this way, by using the measuring instrument 10 and autocollimator 21 as shown in FIG. 2, the elongation dimension of the sample S can be easily determined.
また測定器１０の反射板５０回回動角をオートコリメー
タ２１で光学的に測定して試料Ｓの伸びを測定するので
、試ｎＳに取付けられる測定器１０に電気的な配Ｎを接
続する必要がなく、機器の設置も容易に行うことができ
る。さらに測定器１０を軽湯に形成覆ることができるの
で試料Ｓに負荷が掛らず、聚らかい材料の伸びの測定に
も用いることができる。In addition, since the elongation of the sample S is measured by optically measuring the 50-turn rotation angle of the reflector of the measuring device 10 with the autocollimator 21, it is necessary to connect the electrical wiring N to the measuring device 10 attached to the sample S. Therefore, the equipment can be easily installed. Furthermore, since the measuring instrument 10 can be covered with light water, no load is applied to the sample S, and it can also be used to measure the elongation of soft materials.
第４図は、反射板５を回動触針４に対して直交する方向
、即ら試料Ｓ表面と平行に設置」た例を示すもので、こ
の反射板４の方向に応じて反射板４の回動角度を測定す
るオートコリメータ２１等を配設することにより、上記
第３図に示す実施例と同様に試料Ｓの伸びを測定するこ
とができる。このように回動触針４と反射板５との相対
角度は、引張り試験機の構造や測定手段の構成等に応じ
て適宜に設定することができる。FIG. 4 shows an example in which the reflecting plate 5 is installed in a direction perpendicular to the rotating probe 4, that is, parallel to the surface of the sample S. By disposing an autocollimator 21 or the like for measuring the rotation angle of the sample S, the elongation of the sample S can be measured in the same manner as in the embodiment shown in FIG. 3 above. In this way, the relative angle between the rotary stylus 4 and the reflection plate 5 can be appropriately set depending on the structure of the tensile tester, the structure of the measuring means, etc.
さらに測定器１０を、試料Ｓと同一素材、あるいは線膨
張係数が近接している素材で形成することにより、測定
環境の温度変化による測定誤差を無視することができる
。また回動触針４をより確実に試料Ｓの伸びに追随させ
るために、回動触針４の先端４ａをスプリング等で押圧
することもできる。Furthermore, by forming the measuring device 10 from the same material as the sample S or from a material having a linear expansion coefficient close to that of the sample S, measurement errors due to temperature changes in the measurement environment can be ignored. Further, in order to make the rotating stylus 4 follow the elongation of the sample S more reliably, the tip 4a of the rotating stylus 4 can be pressed with a spring or the like.
以上説明したように、本発明は、試料の伸びに追随して
回動する反射板の回動角度を光学的に測定し、該回動角
度により試料の伸びを測定プるので、測定器に電気的な
配線を行う必要がなく、機器の設置等も容易に行うこと
ができるとともに、検知器を軽出化することができ、柔
かい材料に対しても用いることができる。As explained above, the present invention optically measures the rotation angle of a reflector that rotates following the elongation of the sample, and uses the rotation angle to measure the elongation of the sample. There is no need for electrical wiring, equipment can be easily installed, the detector can be made lighter, and it can be used even on soft materials.
第１図は本発明の伸び測定方法の測定原理を説明する図
、第２図は測定器の一実施例を示す斜視図、第３図は検
出手段の一実施例を示す説明図、第４図は検出手段の他
の実施例を示す説明図である。
１・・・保持部材 ２・・・固定触針 ２ａ・・・
先端３・・・回動支軸 ４・・・回動触針 ４ａ・
・・先端５・・・反射板 １０・・・測定器 ２１
・・・オートコリメータ Ｓ・・・試料 ΔＬ・・
・試料の伸びθ・・・反射板の回動角度FIG. 1 is a diagram explaining the measurement principle of the elongation measuring method of the present invention, FIG. 2 is a perspective view showing an embodiment of the measuring device, FIG. 3 is an explanatory diagram showing an embodiment of the detection means, and FIG. The figure is an explanatory diagram showing another embodiment of the detection means. 1... Holding member 2... Fixed stylus 2a...
Tip 3... Rotating shaft 4... Rotating stylus 4a.
...Tip 5...Reflector plate 10...Measuring device 21
...Autocollimator S...Sample ΔL...
・Elongation of the sample θ...Rotation angle of the reflection plate
Claims (1)
料の表面に当接させて試料に固定するとともに、前記保
持部材の他端部に回動可能に設けられた回動触針の先端
を、試料の表面に試料の伸縮に対して追随可能に当接さ
せ、該回動触針と一体的に設けられた反射板の回動角度
を光学的に測定することを特徴とする伸び測定方法。1. A fixed stylus fixed to one end of the holding member, whose tip is brought into contact with the surface of the sample and fixed to the sample, and a rotating stylus rotatably provided at the other end of the holding member. The tip of the probe is brought into contact with the surface of the sample so as to be able to follow the expansion and contraction of the sample, and the rotation angle of a reflector provided integrally with the rotating probe is optically measured. How to measure elongation.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP11967788A JP2576884B2 (en) | 1988-05-17 | 1988-05-17 | Elongation measurement method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP11967788A JP2576884B2 (en) | 1988-05-17 | 1988-05-17 | Elongation measurement method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH01288701A true JPH01288701A (en) | 1989-11-21 |
| JP2576884B2 JP2576884B2 (en) | 1997-01-29 |
Family
ID=14767320
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP11967788A Expired - Fee Related JP2576884B2 (en) | 1988-05-17 | 1988-05-17 | Elongation measurement method |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2576884B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2022224589A1 (en) * | 2021-04-19 | 2022-10-27 | 株式会社日立製作所 | Strain gauge device, strain gauge system, and laser light emitter/receiver |
-
1988
- 1988-05-17 JP JP11967788A patent/JP2576884B2/en not_active Expired - Fee Related
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2022224589A1 (en) * | 2021-04-19 | 2022-10-27 | 株式会社日立製作所 | Strain gauge device, strain gauge system, and laser light emitter/receiver |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2576884B2 (en) | 1997-01-29 |
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