JPH08166333A - Estimation method of bend-resistant life of composite body and evaluation method of bend-resistant property of composite body - Google Patents
Estimation method of bend-resistant life of composite body and evaluation method of bend-resistant property of composite bodyInfo
- Publication number
- JPH08166333A JPH08166333A JP2310095A JP2310095A JPH08166333A JP H08166333 A JPH08166333 A JP H08166333A JP 2310095 A JP2310095 A JP 2310095A JP 2310095 A JP2310095 A JP 2310095A JP H08166333 A JPH08166333 A JP H08166333A
- Authority
- JP
- Japan
- Prior art keywords
- bend
- composite
- bending
- bending resistance
- life
- 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.)
- Pending
Links
Landscapes
- Investigating Strength Of Materials By Application Of Mechanical Stress (AREA)
Abstract
Description
【0001】[0001]
【産業上の利用分野】本発明は、導体を絶縁体で被覆し
た構成をなす複合体の耐屈曲寿命を予測する方法、及
び、このような複合体の耐屈曲性を評価する方法に関す
る。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of predicting the flex life of a composite having a conductor covered with an insulator, and a method of evaluating the flex resistance of such a composite.
【0002】[0002]
【従来の技術】電線,フラットケーブル,FPC(Flex
ible Printed Circuit:フレキシブルプリント配線板)
等のような、導体を絶縁材料にて被覆してなる複合体の
耐屈曲性を評価する方法として、従来から以下に示すよ
うな方法が広く行われている。図10はこのような従来の
評価試験方法の実施状態を示す図である。2. Description of the Related Art Electric wires, flat cables, FPC (Flex
ible Printed Circuit: Flexible Printed Circuit Board)
As a method for evaluating the bending resistance of a composite body obtained by coating a conductor with an insulating material as described above, the following methods have been widely used. FIG. 10 is a diagram showing a state of implementation of such a conventional evaluation test method.
【0003】図10(a)は、一方の側にのみよく曲げる
ような用途の複合体に対する摺動屈曲評価試験の実施状
態を示しており、試料となる複合体1を、距離2Rを隔
てて対向配置した2枚の平行板2a, 2bの間に、折り曲げ
て挟み込み、一方の平行板2aは固定し他方の平行板2bは
摺動させながら、複合体1の外側,内側を一定にして、
繰り返し屈曲させる。この試験方法では、複合体1が半
円状に屈曲していると仮定し、面間隔2Rを直径として
2枚の平行板2a, 2bに接する半円を理想半円と定義し、
その理想半円の半径Rを屈曲半径という。FIG. 10 (a) shows a state in which a sliding / bending evaluation test is performed on a composite for an application in which only one side is well bent. The composite 1 as a sample is separated by a distance 2R. Between the two parallel plates 2a and 2b arranged facing each other, it is bent and sandwiched, one parallel plate 2a is fixed and the other parallel plate 2b is slid, while the outer side and the inner side of the composite body 1 are fixed,
Bend repeatedly. In this test method, it is assumed that the composite 1 is bent in a semicircular shape, and the semicircle in contact with the two parallel plates 2a and 2b with the surface spacing 2R as the diameter is defined as an ideal semicircle.
The radius R of the ideal semicircle is called the bending radius.
【0004】一方、図10(b)は、両側にわたって曲げ
るような用途の複合体に対するMIT屈曲評価試験の実
施状態を示しており、試料となる複合体1を、所定の曲
率半径Rを有する2個の治具3a, 3bの周面に交互に巻き
付ける事によって、複合体1の外側,内側を反転させな
がら繰り返し屈曲させる。この図10(b)に示す場合に
も、球面体3a, 3bの周面に沿った屈曲半径Rの理想半円
が定義される。On the other hand, FIG. 10 (b) shows a state in which the MIT bending evaluation test is performed on a composite for a purpose of bending over both sides, and a composite 1 as a sample has a predetermined radius of curvature R2. By alternately winding the jigs 3a and 3b around the peripheral surfaces, the outer and inner sides of the composite 1 are inverted and repeatedly bent. Also in the case shown in FIG. 10B, an ideal semicircle having a bending radius R along the peripheral surfaces of the spherical bodies 3a and 3b is defined.
【0005】以上のようにして、評価対象の複合体を何
回も繰り返して屈曲させ、その導体部の抵抗値が所定値
(例えば、初期値の120 %)に増加するまでの屈曲回数
を測定し、その測定回数に応じて各複合体の耐屈曲性を
評価している。また、導体部の抵抗値が所定値に到達し
たときの屈曲回数を、耐屈曲寿命と定義する。As described above, the composite to be evaluated is repeatedly bent many times, and the number of times of bending until the resistance value of the conductor portion increases to a predetermined value (for example, 120% of the initial value) is measured. The flex resistance of each composite is evaluated according to the number of measurements. In addition, the number of times of bending when the resistance value of the conductor reaches a predetermined value is defined as the bending resistance life.
【0006】[0006]
【発明が解決しようとする課題】従来の複合体の評価方
法では、試料としての複合体を試験装置に取り付ける際
には、図11(a)に示すように、平行板2a, 2bに対して
試料たる複合体1を垂直にする必要がある。しかし、常
に図11(a)に示すような状態で取り付けることは困難
であり、図11(b)に示すようにずれた状態で取り付け
られることがある。また、試料としての複合体を作製す
る際に、設定値の寸法上の差異も生じる。従って、得ら
れた耐屈曲性の評価結果に誤差, バラツキが発生するの
で、信頼性が高い評価結果を得るためには、条件(導体
部,絶縁部の材料及び厚さ並びに評価時の屈曲半径)を
同一にした試料を複数回にわたって試験しなければなら
なかった。According to the conventional method for evaluating a composite, when the composite as a sample is attached to the test apparatus, as shown in FIG. 11 (a), the parallel plates 2a and 2b are attached to the parallel plates 2a and 2b. It is necessary to make the sample composite body 1 vertical. However, it is difficult to always attach in the state shown in FIG. 11 (a), and sometimes it is attached in a displaced state as shown in FIG. 11 (b). In addition, when a composite as a sample is produced, a dimensional difference in set value occurs. Therefore, errors and variations will occur in the obtained bending resistance evaluation results, so in order to obtain highly reliable evaluation results, the conditions (material and thickness of the conductor and insulating parts, and the bending radius at the time of evaluation) ) Identical sample had to be tested multiple times.
【0007】また、上記条件を変更する毎に、その試料
の作製,試験を行わなければならず、評価結果を得るた
めに多大な労力と時間とを必要とするという問題があっ
た。Further, every time the above conditions are changed, the sample must be prepared and tested, which requires a great deal of labor and time to obtain the evaluation result.
【0008】本発明は斯かる事情に鑑みてなされたもの
であり、導体を絶縁体で被覆した構成をなす複合体の耐
屈曲寿命を極めて容易にしかも正確に予測できる複合体
の耐屈曲寿命予測方法を提供することを目的とする。The present invention has been made in view of the above circumstances, and it is extremely easy and accurate to predict the flex life of a composite having a conductor covered with an insulator. The purpose is to provide a method.
【0009】また、本発明の他の目的は、上述のような
誤差,バラツキがない正確な複合体の耐屈曲性の評価結
果を得ることができる複合体の耐屈曲性評価方法を提供
することにある。Another object of the present invention is to provide a flexural resistance evaluation method for a composite, which can obtain an accurate flexural resistance evaluation result of the composite without the above-mentioned errors and variations. It is in.
【0010】[0010]
【課題を解決するための手段】以下、本発明の考案に到
った経緯について簡単に説明する。複合体を構成する材
料及びその構造により複合体の耐屈曲寿命が変化するの
は、耐屈曲性を決定づける何らかの要因が存在するため
であり、それを知ることができれば、耐屈曲寿命の容易
な予測が可能であると本発明者等は考えた。耐屈曲性評
価試験装置に試料(複合体)を装着した際に導体部の歪
み量が大きいことは、その部分に発生する応力が大きい
ことと同義である。ここで、導体単独にて耐屈曲性評価
試験を施した場合に、図12に示すように、導体に加える
引張り応力が大きくなる程、耐屈曲寿命は低下する。よ
って、複合体においても導体部に発生する最大歪み量が
大きくなる程、その部分に加わる応力が大きくなって耐
屈曲寿命は低下すると考えられる。従って、耐屈曲性評
価試験装置に試料(複合体)を装着した際に導体部に発
生する最大歪み量が耐屈曲寿命を決定する要因であると
いう知見を得るに到った。The background to the invention of the present invention will be briefly described below. The reason why the flex life of the composite changes depending on the material constituting the composite and its structure is that there is some factor that determines the flex resistance, and if this can be known, it is possible to easily predict the flex life. The inventors of the present invention considered that it is possible. A large amount of strain in the conductor portion when the sample (composite body) is attached to the bending resistance evaluation test device is synonymous with a large stress generated in that portion. Here, when the bending resistance evaluation test is performed on the conductor alone, as shown in FIG. 12, the bending resistance life decreases as the tensile stress applied to the conductor increases. Therefore, it is considered that, even in the composite body, as the maximum strain amount generated in the conductor portion increases, the stress applied to that portion increases and the flexing resistance life decreases. Therefore, it has been found that the maximum strain amount generated in the conductor portion when the sample (composite body) is attached to the bending resistance evaluation test device is a factor that determines the bending resistance life.
【0011】これまでの耐屈曲性評価試験装置により複
合体の耐屈曲性を評価する場合、屈曲半径が一定である
ときを捉えて、複合体の被覆部である絶縁体の厚さが同
じであれば、図10(a),(b)に示すように、屈曲時
の導体部の最大歪み量は一定であると考えられてきた。
しかしながら、導体部の最大歪み量が耐屈曲寿命を決定
する要因であるという知見に基づいて、実際は理想的な
屈曲半径を常に維持して屈曲されているのではないこと
を、本発明者等は明らかにした。図13はこの状態を示す
図であり、図13(a),図13(b)はそれぞれ図10
(a),図10(b)に対応している。図13(a),
(b)の破線に示す如く同じ屈曲半径の理想半円で屈曲
していると考えられていた場合でも、実際には図13
(a),(b)の太実線に示すように、複合体1の屈曲
状態が異なっており、必ずしも設定条件通りには屈曲し
ていない。When the bending resistance of a composite is evaluated by the conventional bending resistance evaluation test apparatus, the case where the bending radius is constant is detected and the thickness of the insulator, which is the covering portion of the composite, is the same. If so, as shown in FIGS. 10 (a) and 10 (b), it has been considered that the maximum strain amount of the conductor portion during bending is constant.
However, on the basis of the finding that the maximum strain amount of the conductor portion is a factor that determines the bending resistance life, the present inventors have found that in reality, the bending is not always performed while maintaining an ideal bending radius. Revealed. FIG. 13 is a diagram showing this state, and FIGS. 13 (a) and 13 (b) respectively show FIG.
This corresponds to (a) and FIG. 10 (b). Figure 13 (a),
Even if it is considered that the wire is bent in an ideal semicircle with the same bending radius as shown by the broken line in (b), it is actually shown in FIG.
As shown by the thick solid lines in (a) and (b), the bending state of the composite 1 is different, and the bending is not necessarily performed according to the set conditions.
【0012】また、試料としての複合体1を耐屈曲性評
価試験装置に装着した際に、図13(a),(b)の太実
線に示す複合体1の屈曲形状が、図13(a),(b)の
破線に示す理想半円からどの程度ずれているかも、耐屈
曲寿命を予測する指標となり得る。複合体1の屈曲形状
が理想半円から大きくずれておれば導体に局所的に大き
な応力が加わるため、一般的に耐屈曲寿命は短く、あま
りずれていなければ一般的に耐屈曲寿命は長いと言え
る。When the composite 1 as a sample is mounted on the bending resistance evaluation test apparatus, the bent shape of the composite 1 shown by the thick solid lines in FIGS. 13 (a) and 13 (b) is as shown in FIG. ) And (b) deviate from the ideal semicircle indicated by the broken line, which can also be an index for predicting the flex life. If the bending shape of the composite 1 is largely deviated from the ideal semicircle, a large stress is locally applied to the conductor, so that the flexing life is generally short, and if not so much, the flexing life is generally long. I can say.
【0013】従って、予め異なる条件(導体部,絶縁部
の材料及び厚さ並びに屈曲半径)の複数の試料(複合
体)について、それぞれを耐屈曲性評価試験装置に装着
した際の導体部の最大歪み量または屈曲形状の理想半円
からのずれ量と耐屈曲寿命とを求めて得られた関係を示
す、図14に示すようなマスターカーブを予め作成してお
けば、他の条件の試料(複合体)について、その試料を
耐屈曲性評価試験装置に装着した場合の導体部の最大歪
み量または屈曲形状の理想半円からのずれ量を求めるこ
とにより、このマスターカーブを参照してその試料の耐
屈曲寿命を予測することができる。Therefore, for a plurality of samples (composites) under different conditions (materials and thicknesses of conductors and insulating parts, and bending radii) in advance, the maximum of the conductors when each was mounted in the bending resistance evaluation test device If a master curve as shown in FIG. 14 is created in advance, showing the relationship obtained by obtaining the amount of strain or the amount of deviation from the ideal semicircle of the bending shape and the bending resistance life, the sample under other conditions ( For the composite), the sample is referred to this master curve by obtaining the maximum strain amount of the conductor part or the deviation of the bent shape from the ideal semicircle when the sample is mounted in the bending resistance evaluation test device. It is possible to predict the flex life.
【0014】本願の請求項1に係る複合体の耐屈曲寿命
予測方法は、導体部を絶縁部で被覆してなる複合体につ
いて、耐屈曲性評価試験装置を用いて、その導体部の抵
抗値が所定値に到達したときの屈曲回数で定義される耐
屈曲寿命を予測する方法において、複合体を耐屈曲性評
価試験装置に装着した際の導体部の最大歪み量及び/ま
たは屈曲形状の理想半円からのずれ量と実測した耐屈曲
寿命との関係を予め求めておき、耐屈曲性評価試験装置
に予測対象の複合体を装着した際の導体部の最大歪み量
及び/または屈曲形状の理想半円からのずれ量を求めて
おいた関係に照合して複合体の耐屈曲寿命を予測するこ
とを特徴とする。The method for predicting the flexural life of a composite according to claim 1 of the present application is such that the resistance of the conductive part of a composite in which the conductive part is covered with an insulating part is measured using a flexural resistance evaluation test device. In the method of predicting the flexing resistance life defined by the number of flexing times when reaches a predetermined value, the maximum strain amount and / or the ideal bending shape of the conductor part when the composite is mounted on the flexing resistance evaluation test device The relationship between the amount of deviation from the semicircle and the measured bending resistance life is obtained in advance, and the maximum amount of strain and / or bending shape of the conductor part when the composite to be predicted is attached to the bending resistance evaluation test device is determined. It is characterized in that the bending resistance life of the composite is predicted by collating with the relationship in which the amount of deviation from the ideal semicircle has been obtained.
【0015】本願の請求項2に係る複合体の耐屈曲性評
価方法は、導体部を絶縁部で被覆してなる複合体につい
て、耐屈曲性評価試験装置を用いて、その耐屈曲性を評
価する方法において、複数の複合体を耐屈曲性評価試験
装置にそれぞれ装着した際の導体部の最大歪み量及び/
または屈曲形状の理想半円からのずれ量に基づいて、こ
れらの複数の複合体の耐屈曲性を相対的に評価すること
を特徴とする。The flex resistance evaluation method for a composite according to claim 2 of the present application evaluates the flex resistance of a composite in which a conductor part is covered with an insulating part by using a flex resistance evaluation tester. Method, the maximum strain amount of the conductor part and //
Alternatively, the bending resistance of the plurality of composites is relatively evaluated based on the deviation amount of the bent shape from the ideal semicircle.
【0016】[0016]
【作用】請求項1の発明では、耐屈曲性評価試験装置に
装着した場合の導体部の最大歪み量及び/または屈曲形
状の理想半円からのずれ量と耐屈曲寿命実験結果との関
係を示すマスターカーブを予め作成しておき、寿命予測
対象の複合体を耐屈曲性評価試験装置に装着した際の導
体部の最大歪み量及び/または屈曲形状の理想半円から
のずれ量を求め、求めた最大歪み量及び/または屈曲形
状の理想半円からのずれ量を作成しておいたこのマスタ
ーカーブに照らし合わせて、その複合体の耐屈曲寿命を
予測する。よって、極めて容易に複合体の耐屈曲寿命を
予測できる。According to the first aspect of the present invention, the relationship between the maximum strain amount of the conductor portion and / or the deviation amount of the bent shape from the ideal semicircle and the result of the bending resistance life test when mounted on the bending resistance evaluation test device is shown. A master curve shown in advance is created in advance, and the maximum strain amount of the conductor part and / or the deviation amount from the ideal semicircle of the bent shape when the composite of the life prediction target is attached to the bending resistance evaluation test device is obtained, The bending resistance life of the composite is predicted by comparing the obtained maximum strain amount and / or the deviation amount of the bent shape from the ideal semicircle with the prepared master curve. Therefore, the flex life of the composite can be predicted very easily.
【0017】請求項2の発明では、前述したように耐屈
曲性評価試験装置に複合体を装着した際の導体部の最大
歪み量及び屈曲形状の理想半円からのずれ量が耐屈曲寿
命を決定する要因であるので、上述したようなマスター
カーブが予め作成されていない場合でも、異なる条件の
それぞれの複合体を耐屈曲性評価試験装置に装着した際
の導体部の最大歪み量及び/または屈曲形状の理想半円
からのずれ量を求めて比較することにより、異なる条件
の複数の複合体の耐屈曲性を相対的に比較評価すること
が可能である。According to the second aspect of the present invention, as described above, the maximum strain amount of the conductor portion and the deviation amount of the bent shape from the ideal semicircle when the composite is mounted on the bending resistance evaluation test device indicate the bending resistance life. Since it is a factor to determine, even if the above-mentioned master curve is not created in advance, the maximum strain amount and / or the maximum strain amount of the conductor part when each composite under different conditions is attached to the bending resistance evaluation test device. By obtaining and comparing the deviation amount of the bent shape from the ideal semicircle, it is possible to relatively compare and evaluate the bending resistance of a plurality of composites under different conditions.
【0018】[0018]
【実施例】以下、本発明の実施例について説明する。Embodiments of the present invention will be described below.
【0019】以下に述べる実施例では、複合体として、
図1に示すような、導体11を接着剤12を介して絶縁フィ
ルム13にて被覆したフラットケーブル10を使用する。導
体11, 絶縁フィルム13はそれぞれ軟銅, ポリエステルフ
ィルムからなり、接着剤12としてポリエステル系接着剤
を使用する。また、耐屈曲性評価試験装置としては、図
10(a)に示すようなU字摺動屈曲試験装置を用いる。In the examples described below, as a composite,
As shown in FIG. 1, a flat cable 10 in which a conductor 11 is covered with an insulating film 13 via an adhesive 12 is used. The conductor 11 and the insulating film 13 are made of annealed copper and polyester film, respectively, and a polyester adhesive is used as the adhesive 12. In addition, as a bending resistance evaluation test device,
A U-shaped sliding bending test device as shown in 10 (a) is used.
【0020】まず、導体11,接着剤12,絶縁フィルム13
の厚さが異なる複数種のフラットケーブル10を試料とし
て作製し、評価試験時の屈曲半径Rを変化させて、これ
らを耐屈曲性評価試験装置に装着した場合の導体11の最
大歪み量を求める。なお、このようなフラットケーブル
10にあっては、導体11の屈曲形状を直接に捉えることは
できないので、コンピュータを使用して有限要素法によ
り屈曲時の導体11の最大歪み量を算出する。First, the conductor 11, the adhesive 12, the insulating film 13
A plurality of types of flat cables 10 having different thicknesses are prepared as samples, the bending radius R at the time of the evaluation test is changed, and the maximum strain amount of the conductor 11 when these are attached to the bending resistance evaluation test device is obtained. . In addition, such a flat cable
In the case of 10, since the bent shape of the conductor 11 cannot be directly grasped, the maximum strain amount of the conductor 11 at the time of bending is calculated by a finite element method using a computer.
【0021】また、作製した複数種のフラットケーブル
10を試料として、評価試験時の屈曲半径Rを変化させ
て、耐屈曲性評価試験装置に装着した場合の屈曲形状の
理想半円からのずれ量を求める。この場合のずれ量につ
いては、以下の3種の長さ(曲率半径,第1距離,第2
距離)の何れかを測定することにより評価する。図2
は、ずれ量の1つの指標となる曲率半径rの定義を示す
模式図である。複合体としてのフラットケーブル10を2
枚の平行板2a, 2bに挟んで屈曲させた場合に、フラット
ケーブル10の導体11の屈曲部頂点近傍の内側に接するこ
とができる最大円(破線で示す)の半径を曲率半径rと
定義する。また、図3は、ずれ量の他の指標となる第1
距離d1の定義を示す模式図である。複合体としてのフ
ラットケーブル10を2枚の平行板2a, 2bに挟んで屈曲さ
せた場合に、半径Rの理想半円(破線で示す)に屈曲さ
せたときにフラットケーブル10が平行板2a, 2bから離れ
始める位置からフラットケーブル10の実際の位置までの
距離を第1距離d1と定義する。更に、図4は、ずれ量
の更に他の指標となる第2距離d2の定義を示す模式図
である。複合体としてのフラットケーブル10を2枚の平
行板2a, 2bに挟んで屈曲させた場合に、フラットケーブ
ル10が平行板2a, 2bから離れ始める位置を半径Rの理想
半円(破線で示す)と一致させた際のフラットケーブル
10の屈曲部の頂点と理想半円との距離を第2距離d2と
定義する。屈曲時のフラットケーブル10が理想半円に近
づく程、曲率半径rは大きくなって理想半円の半径Rに
近づき、第1距離d1及び第2距離d2は小さくなって
0に近づく。Further, a plurality of types of flat cables produced
Using 10 as a sample, the bending radius R at the time of the evaluation test is changed, and the amount of deviation of the bent shape from the ideal semicircle when attached to the bending resistance evaluation test device is determined. Regarding the amount of deviation in this case, the following three types of lengths (curvature radius, first distance, second
It is evaluated by measuring any of the distances. Figure 2
[Fig. 3] is a schematic diagram showing a definition of a radius of curvature r which is one index of a deviation amount. 2 flat cables 10 as a composite
The radius of the largest circle (indicated by the broken line) that can contact the inside of the conductor 11 of the flat cable 10 in the vicinity of the apex of the bent portion when it is bent by sandwiching it between the parallel plates 2a and 2b is defined as the radius of curvature r. . In addition, FIG. 3 shows the first index which is another index of the shift amount.
It is a schematic diagram which shows the definition of the distance d1. When the flat cable 10 as a composite is bent by sandwiching it between two parallel plates 2a, 2b, when the flat cable 10 is bent into an ideal semicircle with a radius R (shown by a broken line), The distance from the position starting from 2b to the actual position of the flat cable 10 is defined as the first distance d1. Further, FIG. 4 is a schematic diagram showing the definition of the second distance d2 which is another index of the shift amount. When the flat cable 10 as a composite body is sandwiched between two parallel plates 2a and 2b and bent, the position where the flat cable 10 starts to separate from the parallel plates 2a and 2b is an ideal semicircle with a radius R (shown by a broken line). Flat cable when matched with
The distance between the apex of the 10 bends and the ideal semicircle is defined as the second distance d2. As the flat cable 10 at the time of bending approaches the ideal semicircle, the radius of curvature r increases and approaches the radius R of the ideal semicircle, and the first distance d1 and the second distance d2 decrease and approach zero.
【0022】上述した3種のずれ量は、屈曲時の導体11
の最大歪み量と同様に、有限要素法による計算によって
算出可能である。また、図5に示すような観察用治具20
を使用すれば、顕微鏡観察にてこれらの3種のずれ量は
測定可能である。観察用治具20は、「コ」の字状をなす
板材からなり、対向する平行部20a, 20b間の内のりは屈
曲半径の2倍(2R)である。また、対向する各平行部
20a, 20bには残りの辺部20c からRの距離の位置に目印
21, 21が付けられている。また、辺部20c の中央(各平
行部20a, 20bからそれぞれRの距離の位置)にも目印21
が付けられている。このような観察用治具20にフラット
ケーブル10を装着して屈曲させることにより、目印21か
らのずれ等を顕微鏡で観察して3種のずれ量を測定でき
る。但し、曲率半径rについては、フラットケーブル10
の接着剤12及び絶縁フィルム13が透明性を有する場合、
または、フラットケーブル10の下側に光源を設けて導体
11が影となって観察できる場合に限ってのみ、顕微鏡観
察が可能である。The above-mentioned three types of deviations are the same as the conductor 11 when bent.
Like the maximum strain amount of, it can be calculated by the finite element method. In addition, the observation jig 20 as shown in FIG.
If the above is used, these three kinds of shift amounts can be measured by microscopic observation. The observing jig 20 is made of a plate material having a "U" shape, and the inner distance between the parallel portions 20a and 20b facing each other is twice the bending radius (2R). In addition, each parallel part that faces
Mark on 20a and 20b at the distance R from the remaining side 20c.
21, 21 are attached. In addition, a mark 21 is also provided at the center of the side portion 20c (the position of the distance R from each parallel portion 20a, 20b).
Is attached. By mounting the flat cable 10 on the observing jig 20 and bending it, it is possible to measure three kinds of deviation amounts by observing the deviation from the mark 21 with a microscope. However, regarding the radius of curvature r, the flat cable 10
When the adhesive 12 and the insulating film 13 of have transparency,
Alternatively, place a light source under the flat cable 10
Microscopic observation is possible only when 11 can be observed as a shadow.
【0023】なお、本実施例では、導体11の最大歪み量
及び屈曲形状の理想半円からのずれ量(上述の3種のず
れ量)は何れも、コンピュータによる計算結果により求
めた。試料の構造,構成材料の物理定数,屈曲条件(屈
曲半径,試験温度等)に基づいて、コンピュータにて最
大歪み量及び理想半円からのずれ量(曲率半径,第1距
離,第2距離)の算出は可能である。また、これらと同
じ条件下での各試料の耐屈曲寿命を実験的に求める。こ
の際、耐屈曲寿命とは、前述したように、導体11の抵抗
値が初期値の120 %に達するまでの屈曲回数を表すこと
とする。In this embodiment, both the maximum strain amount of the conductor 11 and the deviation amount of the bent shape from the ideal semicircle (the above-mentioned three kinds of deviation amounts) were obtained from the calculation results by the computer. Based on the structure of the sample, physical constants of the constituent materials, and bending conditions (bending radius, test temperature, etc.), the maximum strain amount and deviation from the ideal semicircle (curvature radius, first distance, second distance) are calculated by the computer. Can be calculated. Also, the flex life of each sample under the same conditions as these is experimentally obtained. At this time, the bending resistance life represents the number of times of bending until the resistance value of the conductor 11 reaches 120% of the initial value, as described above.
【0024】このようにして求めた導体11の最大歪み量
及び屈曲形状の理想半円からのずれ量と耐屈曲寿命との
関係を示すマスターカーブを作成する。図6〜図9は、
これらの作成したマスターカーブを表している。図6
は、最大歪み量と耐屈曲寿命との関係を示すマスターカ
ーブであり、横軸は最大歪み量を歪み率(%)で示し、
縦軸は耐屈曲寿命を対数軸(回)にて示す。また、図7
は、上述した定義による導体11の曲率半径rと耐屈曲寿
命との関係を示すマスターカーブであり、横軸は曲率半
径r(mm)を示し、縦軸は耐屈曲寿命を対数軸(回)
にて示す。また、図8は、上述した定義による第1距離
d1と耐屈曲寿命との関係を示すマスターカーブであ
り、横軸は第1距離d1(mm)を示し、縦軸は耐屈曲
寿命を対数軸(回)にて示す。更に、図9は、上述した
定義による第2距離d2と耐屈曲寿命との関係を示すマ
スターカーブであり、横軸は第2距離d2(mm)を示
し、縦軸は耐屈曲寿命を対数軸(回)にて示す。なお、
図6〜図9の各A〜I点における試料の構造及び試験条
件は、下記第1表に示す通りである。なお、第1距離d
1,第2距離d2に基づく耐屈曲寿命の予測は、試験時
の屈曲半径Rが等しい場合にのみ行えるので、第1距離
d1,第2距離d2については、屈曲半径Rを等しくし
た場合についてのデータのみからマスターカーブを作成
している(図8,図9参照)。A master curve showing the relationship between the maximum strain amount of the conductor 11 thus obtained and the deviation amount of the bending shape from the ideal semicircle and the bending resistance life is created. 6 to 9 show
It represents these created master curves. Figure 6
Is a master curve showing the relationship between the maximum strain amount and flex life, the horizontal axis shows the maximum strain amount in strain rate (%),
The vertical axis represents the bending resistance life on a logarithmic axis (times). Also, FIG.
Is a master curve showing the relationship between the radius of curvature r of the conductor 11 and the bending resistance life according to the above definition, the horizontal axis represents the curvature radius r (mm), and the vertical axis represents the bending resistance life in the logarithmic axis (times).
Shown in. Further, FIG. 8 is a master curve showing the relationship between the first distance d1 and the bending resistance life according to the above definition, the horizontal axis represents the first distance d1 (mm), and the vertical axis represents the bending resistance life in the logarithmic axis. Indicated in (times). Further, FIG. 9 is a master curve showing the relationship between the second distance d2 and the bending resistance life according to the above definition, the horizontal axis shows the second distance d2 (mm), and the vertical axis shows the bending resistance life. Indicated in (times). In addition,
The structure and test conditions of the sample at points A to I in FIGS. 6 to 9 are as shown in Table 1 below. The first distance d
Since the bending resistance life prediction based on the first and second distances d2 can be performed only when the bending radii R at the time of the test are the same, the first distance d1 and the second distance d2 are the same when the bending radii R are the same. A master curve is created only from the data (see FIGS. 8 and 9).
【0025】[0025]
【表1】 [Table 1]
【0026】そして、この作成した図6,図7,図8ま
たは図9に示すマスターカーブを参照して、他の条件の
フラットケーブル10の耐屈曲寿命を予測する。即ち、予
測したいフラットケーブル10を耐屈曲性評価試験装置に
装着した場合の導体11の最大歪み量,曲率半径r,第1
距離d1または第2距離d2の何れかをコンピュータに
て算出し、算出した最大歪み量,曲率半径,第1距離ま
たは第2距離を図6,図7,図8または図9に示すマス
ターカーブに照らし合わせて、そのフラットケーブル10
の耐屈曲寿命を予測する。このようなマスターカーブを
備えておくと、耐屈曲性評価試験装置に装着した際の導
体11の最大歪み量,曲率半径,第1距離または第2距離
を求めるだけで、フラットケーブル10の耐屈曲寿命の予
測を容易に行える。Then, referring to the created master curves shown in FIG. 6, FIG. 7, FIG. 8 or FIG. 9, the flex life of the flat cable 10 under other conditions is predicted. That is, when the flat cable 10 to be predicted is mounted on the bending resistance evaluation test device, the maximum strain amount of the conductor 11, the radius of curvature r, the first
Either the distance d1 or the second distance d2 is calculated by a computer, and the calculated maximum strain amount, radius of curvature, first distance or second distance is converted into the master curve shown in FIG. 6, FIG. 7, FIG. 8 or FIG. The flat cable 10 against
Predict the flex life. If such a master curve is provided, the bending resistance of the flat cable 10 can be obtained by simply obtaining the maximum strain amount, the radius of curvature, the first distance or the second distance of the conductor 11 when mounted on the bending resistance evaluation test device. The life can be easily predicted.
【0027】また、有限要素法により算出した屈曲時の
導体11の最大歪み量,曲率半径,第1距離または第2距
離の何れかにて耐屈曲寿命を評価する場合は、従来例で
は避けられなかった誤差, バラツキをなくすことが可能
となり、耐屈曲寿命の向上に有効な条件をより正確に探
索できる。つまり、本実施例による複合体の耐屈曲寿命
予測方法から得られる評価結果は、実験的に行う従来の
評価方法と比較して信頼性の点で優れている。In addition, when the flex life is evaluated by the maximum strain amount of the conductor 11 at the time of bending calculated by the finite element method, the radius of curvature, or the first distance or the second distance, it is avoided in the conventional example. It is possible to eliminate errors and variations that were not present, and it is possible to more accurately search for conditions effective in improving the flex life. That is, the evaluation results obtained from the flexural life prediction method of the composite according to this example are superior in reliability as compared with the conventional evaluation method performed experimentally.
【0028】ところで、耐屈曲寿命の実験結果がなくて
も、導体11の最大歪み量が小さい程、または、屈曲形状
の理想半円からのずれ量が小さい程(曲率半径rが大き
い程、第1距離d1,第2距離d2が小さい程)、優れ
た耐屈曲性を有するフラットケーブル10であることは確
認できる。よって、上述したようなマスターカーブを準
備していない場合にあっても、異なる条件のフラットケ
ーブル10における屈曲時の導体11の最大歪み量、また
は、屈曲形状の理想半円からのずれ量を求めて比較する
ことにより、耐屈曲性の相対的な比較を行える。そし
て、このことは、耐屈曲性の向上に有利な条件の探究に
利用できる。Even if there is no experimental result of flex life, the smaller the maximum strain amount of the conductor 11 or the smaller the deviation of the bent shape from the ideal semicircle (the larger the radius of curvature r, It can be confirmed that the flat cable 10 has excellent bending resistance as the first distance d1 and the second distance d2 decrease. Therefore, even when the master curve as described above is not prepared, the maximum strain amount of the conductor 11 at the time of bending in the flat cable 10 under different conditions, or the deviation amount from the ideal semicircle of the bent shape is obtained. By making a comparison, the relative bending resistance can be compared. And this can be utilized for exploring conditions advantageous for improving flex resistance.
【0029】なお、上述の実施例では、軟銅からなる導
体と、ポリエステルフィルムからなる絶縁体と、ポリエ
ステル系材料からなる接着剤とから構成したフラットケ
ーブルを複合体として使用し、U字摺動屈曲試験装置を
耐屈曲性評価試験装置として用い、屈曲形状の理想半円
からのずれ量をすべてコンピュータを用いて求めた場合
について説明したが、これらは単なる例示であり、本発
明において、複合体の構造,構成材料,耐屈曲性評価試
験装置,理想半円からのずれ量の求め方などが上述した
実施例に限定されるものでないことは言うまでもない。In the above embodiment, a flat cable composed of a conductor made of annealed copper, an insulator made of a polyester film, and an adhesive made of a polyester material is used as a composite, and a U-shaped sliding bend is used. The test device was used as a bending resistance evaluation test device, and the case where the amount of deviation from the ideal semicircle of the bent shape was obtained using a computer was described, but these are merely examples, and in the present invention, It goes without saying that the structure, the constituent materials, the bending resistance evaluation test device, and the method of obtaining the amount of deviation from the ideal semicircle are not limited to the above-described embodiments.
【0030】また、上述の実施例では、導体部の最大歪
み量、または、屈曲形状の理想半円からのずれ量の何れ
かに基づいて、耐屈曲寿命の予測,耐屈曲性の相対的比
較を行う場合について説明したが、導体部の最大歪み量
及び屈曲形状の理想半円からのずれ量の両方を鑑みて、
耐屈曲寿命の予測,耐屈曲性の相対的比較を行うように
しても良いことは勿論である。Further, in the above-mentioned embodiment, the bending resistance life is predicted and the relative bending resistance is compared based on either the maximum strain amount of the conductor portion or the deviation amount of the bending shape from the ideal semicircle. However, in consideration of both the maximum strain amount of the conductor portion and the deviation amount from the ideal semicircle of the bent shape,
Of course, it is also possible to make a prediction of flex resistance and to make a relative comparison of flex resistance.
【0031】[0031]
【発明の効果】以上のように、請求項1の発明では、耐
屈曲性評価試験装置に装着した際の複合体の導体部の最
大歪み量及び/または屈曲形状の理想半円からのずれ量
を求めることにより、極めて容易にその複合体の耐屈曲
寿命を予測することが可能である。よって、多数種の複
合体について耐屈曲寿命を求める場合に従来例ではその
試料作製・屈曲試験に必要とした多大な労力と時間とを
削減でき、耐屈曲寿命の向上に好適な条件の探索の効率
化、及び、新製品開発の迅速化を図ることも可能とな
る。また、信頼性の点で優れた評価方法であるので、複
合体の信頼性を裏付ける指標としても利用できる。As described above, according to the first aspect of the invention, the maximum strain amount of the conductor portion of the composite and / or the deviation amount of the bent shape from the ideal semicircle when mounted on the bending resistance evaluation test device. It is possible to predict the flex life of the composite extremely easily by determining Therefore, in the case where the flex life is required for many kinds of composites, the great effort and time required for the sample preparation and flex test in the conventional example can be reduced, and the search for the conditions suitable for improving the flex life can be performed. It is possible to improve efficiency and speed up new product development. Further, since it is an excellent evaluation method in terms of reliability, it can be used as an index for supporting the reliability of the composite.
【0032】また、請求項2の発明では、耐屈曲性評価
試験装置に装着した際の複合体の導体部の最大歪み量及
び/または屈曲形状の理想半円からのずれ量を比較し合
うことにより、異なる種類の複合体の耐屈曲性を相対的
に評価できるので、優れた耐屈曲性を有する複合体の開
発の促進に大いに寄与できる。Further, in the invention of claim 2, the maximum strain amount of the conductor portion of the composite and / or the deviation amount of the bent shape from the ideal semicircle when mounted on the bending resistance evaluation test device are compared with each other. With this, since the flex resistance of different types of composites can be relatively evaluated, it can greatly contribute to the promotion of the development of composites having excellent flex resistance.
【図1】本発明の実施例に用いた複合体(フラットケー
ブル)の構成図である。FIG. 1 is a configuration diagram of a composite body (flat cable) used in an example of the present invention.
【図2】本発明の実施例における屈曲形状の理想半円か
らのずれ量(曲率半径r)の定義を説明するための模式
図である。FIG. 2 is a schematic diagram for explaining the definition of the deviation amount (curvature radius r) from the ideal semicircle of the bent shape in the embodiment of the present invention.
【図3】本発明の実施例における屈曲形状の理想半円か
らのずれ量(第1距離d1)の定義を説明するための模
式図である。FIG. 3 is a schematic diagram for explaining the definition of the deviation amount (first distance d1) of the bent shape from the ideal semicircle in the embodiment of the present invention.
【図4】本発明の実施例における屈曲形状の理想半円か
らのずれ量(第2距離d2)の定義を説明するための模
式図である。FIG. 4 is a schematic diagram for explaining the definition of the deviation amount (second distance d2) of the bent shape from the ideal semicircle in the embodiment of the present invention.
【図5】本発明の実施例において屈曲形状の理想半円か
らのずれ量を観察により求める際に使用する観察用治具
の斜視図である。FIG. 5 is a perspective view of an observing jig used when observing a deviation amount of a bent shape from an ideal semicircle in an example of the present invention.
【図6】本発明の実施例における導体部の最大歪み量と
耐屈曲寿命との関係を示すマスターカーブを表すグラフ
である。FIG. 6 is a graph showing a master curve showing the relationship between the maximum strain amount of the conductor portion and the bending resistance life in the example of the present invention.
【図7】本発明の実施例における曲率半径rと耐屈曲寿
命との関係を示すマスターカーブを表すグラフである。FIG. 7 is a graph showing a master curve showing the relationship between the radius of curvature r and the bending resistance life in the example of the present invention.
【図8】本発明の実施例における第1距離d1と耐屈曲
寿命との関係を示すマスターカーブを表すグラフであ
る。FIG. 8 is a graph showing a master curve showing the relationship between the first distance d1 and the bending resistance life in the example of the present invention.
【図9】本発明の実施例における第2距離d2と耐屈曲
寿命との関係を示すマスターカーブを表すグラフであ
る。FIG. 9 is a graph showing a master curve showing the relationship between the second distance d2 and the bending resistance life in the example of the present invention.
【図10】従来の耐屈曲性評価試験の実施状態を示す模
式図である。FIG. 10 is a schematic view showing an implementation state of a conventional bending resistance evaluation test.
【図11】従来例の問題点を説明するための図である。FIG. 11 is a diagram for explaining a problem of the conventional example.
【図12】導体単独の場合の引張り応力と破断までの屈
曲回数との関係を示すグラフである。FIG. 12 is a graph showing the relationship between the tensile stress and the number of times of bending until breakage when a conductor is used alone.
【図13】耐屈曲性評価試験装置に装着した複合体の屈
曲形状を示す模式図である。FIG. 13 is a schematic view showing a bent shape of a composite body mounted on a bending resistance evaluation test device.
【図14】本発明の概念を説明するためのマスターカー
ブを表すグラフである。FIG. 14 is a graph showing a master curve for explaining the concept of the present invention.
10 フラットケーブル(複合体) 11 導体(軟銅) 12 接着剤(ポリエステル系接着剤) 13 絶縁フィルム(ポリエステルフィルム) 20 観察用治具 10 Flat cable (composite) 11 Conductor (soft copper) 12 Adhesive (polyester adhesive) 13 Insulating film (polyester film) 20 Jig for observation
───────────────────────────────────────────────────── フロントページの続き (72)発明者 二階堂 智史 大阪府大阪市中央区北浜四丁目5番33号 住友電気工業株式会社内 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Satoshi Nikaido 4-5-3 Kitahama, Chuo-ku, Osaka-shi, Osaka Sumitomo Electric Industries, Ltd.
Claims (2)
ついて、耐屈曲性評価試験装置を用いて、その導体部の
抵抗値が所定値に到達したときの屈曲回数で定義される
耐屈曲寿命を予測する方法において、複合体を耐屈曲性
評価試験装置に装着した際の導体部の最大歪み量及び/
または屈曲形状の理想半円からのずれ量と実測した耐屈
曲寿命との関係を予め求めておき、耐屈曲性評価試験装
置に予測対象の複合体を装着した際の導体部の最大歪み
量及び/または屈曲形状の理想半円からのずれ量を求め
ておいた関係に照合して複合体の耐屈曲寿命を予測する
ことを特徴とする複合体の耐屈曲寿命予測方法。1. A composite comprising a conductor part covered with an insulating part is subjected to a bending resistance evaluation test apparatus, and the resistance value is defined by the number of times of bending when the resistance value of the conductor part reaches a predetermined value. In the method of predicting the bending life, the maximum strain amount of the conductor part when the composite is mounted in the bending resistance evaluation test device and / or
Alternatively, the relationship between the amount of deviation of the bent shape from the ideal semicircle and the measured bending resistance life is obtained in advance, and the maximum amount of strain of the conductor part when the composite to be predicted is attached to the bending resistance evaluation test device and And / or a bending resistance life prediction method for a composite, which is characterized by predicting a bending resistance life of the composite by comparing with a relationship in which a deviation amount of a bending shape from an ideal semicircle is obtained.
ついて、耐屈曲性評価試験装置を用いて、その耐屈曲性
を評価する方法において、複数の複合体を耐屈曲性評価
試験装置にそれぞれ装着した際の導体部の最大歪み量及
び/または屈曲形状の理想半円からのずれ量に基づい
て、これらの複数の複合体の耐屈曲性を相対的に評価す
ることを特徴とする複合体の耐屈曲性評価方法。2. A method of evaluating the bending resistance of a composite body obtained by coating a conductor portion with an insulating portion using a bending resistance evaluation test apparatus, wherein a plurality of the composite bodies are subjected to the bending resistance evaluation test apparatus. Characterized in that the bending resistance of the plurality of composites is relatively evaluated based on the maximum strain amount of the conductor part and / or the deviation amount of the bent shape from the ideal semicircle when mounted on Bending resistance evaluation method for composites.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2310095A JPH08166333A (en) | 1994-10-11 | 1995-02-10 | Estimation method of bend-resistant life of composite body and evaluation method of bend-resistant property of composite body |
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP24566494 | 1994-10-11 | ||
JP6-245664 | 1994-10-11 | ||
JP2310095A JPH08166333A (en) | 1994-10-11 | 1995-02-10 | Estimation method of bend-resistant life of composite body and evaluation method of bend-resistant property of composite body |
Publications (1)
Publication Number | Publication Date |
---|---|
JPH08166333A true JPH08166333A (en) | 1996-06-25 |
Family
ID=26360399
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP2310095A Pending JPH08166333A (en) | 1994-10-11 | 1995-02-10 | Estimation method of bend-resistant life of composite body and evaluation method of bend-resistant property of composite body |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPH08166333A (en) |
Cited By (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2001008172A1 (en) * | 1999-07-26 | 2001-02-01 | Sumitomo Wiring Systems, Ltd. | Method of predicting bending life of electric wire or electric wire bundle |
EP1136810A3 (en) * | 2000-03-22 | 2002-02-06 | Sumitomo Wiring Systems, Ltd. | Bend test for a wire harness and device for such a test |
JP2004191361A (en) * | 2002-11-28 | 2004-07-08 | Yazaki Corp | Bending durability prediction method of electric wire and bending protective member, its device and its program |
JP2004191360A (en) * | 2002-11-28 | 2004-07-08 | Yazaki Corp | Flex life prediction method of electric wire and/or electric wire protection member accompanying vibration, its device and its program |
US6839642B2 (en) | 2001-03-02 | 2005-01-04 | Sumitomo Wiring Systems, Ltd. | Flexure life estimating method, wire harness designing method and program thereof |
WO2009110440A1 (en) * | 2008-03-04 | 2009-09-11 | 新日鐵化学株式会社 | Method of predicting bend lifetime of laminated body, prediction device of bend lifetime of laminated body, prediction program of bend lifetime of laminated body, and recording medium |
JP2011091438A (en) * | 2011-01-24 | 2011-05-06 | Nippon Steel Chem Co Ltd | Double-sided flexible circuit board for repeatedly bending use |
WO2013002271A1 (en) * | 2011-06-30 | 2013-01-03 | 大電株式会社 | Method for selecting flex-resistant conductive material, and cable using same |
CN114577451A (en) * | 2022-02-24 | 2022-06-03 | 苏州华星光电技术有限公司 | Method for testing service life of display panel |
-
1995
- 1995-02-10 JP JP2310095A patent/JPH08166333A/en active Pending
Cited By (14)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2001008172A1 (en) * | 1999-07-26 | 2001-02-01 | Sumitomo Wiring Systems, Ltd. | Method of predicting bending life of electric wire or electric wire bundle |
US6439059B1 (en) | 1999-07-26 | 2002-08-27 | Sumitomo Wiring Systems, Ltd. | Method of predicting bending life of electric wire or electric wire bundle |
EP1136810A3 (en) * | 2000-03-22 | 2002-02-06 | Sumitomo Wiring Systems, Ltd. | Bend test for a wire harness and device for such a test |
US6494104B2 (en) | 2000-03-22 | 2002-12-17 | Sumitomo Wiring Systems, Ltd. | Bend test for a wire harness and device for such a test |
US6839642B2 (en) | 2001-03-02 | 2005-01-04 | Sumitomo Wiring Systems, Ltd. | Flexure life estimating method, wire harness designing method and program thereof |
JP2004191360A (en) * | 2002-11-28 | 2004-07-08 | Yazaki Corp | Flex life prediction method of electric wire and/or electric wire protection member accompanying vibration, its device and its program |
JP2004191361A (en) * | 2002-11-28 | 2004-07-08 | Yazaki Corp | Bending durability prediction method of electric wire and bending protective member, its device and its program |
WO2009110440A1 (en) * | 2008-03-04 | 2009-09-11 | 新日鐵化学株式会社 | Method of predicting bend lifetime of laminated body, prediction device of bend lifetime of laminated body, prediction program of bend lifetime of laminated body, and recording medium |
JP5248595B2 (en) * | 2008-03-04 | 2013-07-31 | 新日鉄住金化学株式会社 | Bending life prediction method for laminated body, bending life prediction apparatus for laminated body, bending life prediction program for laminated body, and recording medium |
TWI460425B (en) * | 2008-03-04 | 2014-11-11 | Nippon Steel & Sumikin Chem Co | Method, device, program and recording medium for predicting flex life of laminate |
JP2011091438A (en) * | 2011-01-24 | 2011-05-06 | Nippon Steel Chem Co Ltd | Double-sided flexible circuit board for repeatedly bending use |
WO2013002271A1 (en) * | 2011-06-30 | 2013-01-03 | 大電株式会社 | Method for selecting flex-resistant conductive material, and cable using same |
CN114577451A (en) * | 2022-02-24 | 2022-06-03 | 苏州华星光电技术有限公司 | Method for testing service life of display panel |
CN114577451B (en) * | 2022-02-24 | 2023-08-01 | 苏州华星光电技术有限公司 | Method for testing service life of display panel |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
CN108088753B (en) | Device for evaluating flexural properties of material and evaluation method using same | |
JPH08166333A (en) | Estimation method of bend-resistant life of composite body and evaluation method of bend-resistant property of composite body | |
US5227731A (en) | Method of continuously determining crack length | |
JP5248595B2 (en) | Bending life prediction method for laminated body, bending life prediction apparatus for laminated body, bending life prediction program for laminated body, and recording medium | |
JP2005214969A (en) | Technique for adhering strain gauge to deformable body of force-measuring cell | |
CN109520828B (en) | Elastic modulus testing method of film | |
US20060002815A1 (en) | Corrosion sensing microsensors | |
US7785864B2 (en) | Bio-molecules detecting apparatus using electromagnetic induction and detecting method using the same | |
RU2399031C1 (en) | Pressure sensor with thin-film tensoresistor nano- and micro-electromechanical system | |
CN108548729B (en) | Method and device for measuring maximum bending stress of material | |
JP2008082712A (en) | Pressure sensor element | |
JPH0623700B2 (en) | Method for measuring surface temperature of sensor used in electric heating method | |
JP3898051B2 (en) | Method for predicting flex life of wire or wire bundle | |
CN1206528C (en) | Device for measuring thermal conductivity of conductor thin film | |
Wycherley et al. | A method for uniform shear stress-strain analysis of adhesives | |
EP0414924A1 (en) | Device for determining the parameters of developing surface cracks | |
JP2020063989A (en) | Corrosion sensor | |
US11340261B2 (en) | Flexible electric probe | |
EP3570007A1 (en) | Humidity sensor and corrosion test method using the same | |
Sood et al. | Analysis of a Dynamic Flexed Flat Cable Harness | |
CN113677970A (en) | Sensor for detecting pressure, level, density, temperature, mass and flow | |
JP3045626B2 (en) | Degradation diagnosis method for laminated products | |
JP2004234962A (en) | Flex life prediction method of electric wire | |
JP2021165635A (en) | Sequencing method and sequencing device | |
CN113532287B (en) | DIC-based method for measuring relative slippage of spiral members of marine flexible pipeline |