JPS59124344U

JPS59124344U - Fatigue crack length automatic measuring device

Info

Publication number: JPS59124344U
Application number: JP1874383U
Authority: JP
Inventors: 良之近藤
Original assignee: 三菱重工業株式会社
Priority date: 1983-02-10
Filing date: 1983-02-10
Publication date: 1984-08-21

Abstract

(57)【要約】本公報は電子出願前の出願データであるた
め要約のデータは記録されません。(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Brief explanation of drawings]

第１図は従来の除荷弾性コンプライアンス計測装置の回
路図、第２図は除荷弾性コンプライアンス法による亀裂
長さ較正曲線図、第３図は本考案の疲労亀裂長さ自動計
測装置の一実施例のブロック図、第４図はスリット状態
（亀裂が入っていない）の荷重変位ヒステリシス図、第
５図はスリット状態での引算後荷重−変位ヒステリシス
図、第６図は亀裂成長に伴なう引算後の荷重−変位ヒス
テリシスの変化を示す図、第７図はクラッククローザ現
象による引算後荷重−変位ヒステリシスの変化を示す図
である。１・・田−ドセル、２・・・Ｕリンク、３，４・・・ピ
ン、５・・・Ｕリンク、６・・・試験機アクチュエータ
、７・・・除荷弾性コンプライアンス計測装置、８・・
・引算量調節用ポテンショメータ、９・・・微分範囲設
定器、１０・・・第１微分器、１１・・・第２微分器、
１２・・・亀裂長さ設定器、１３・・・試験機停止信号
発生装置、１４・・・アナログ割算器、１５・・・演算
装置、１６・・・疲労亀裂長さ自動計測装置、１７・・
・試験片、１８゜１９・・・ロッド、２０・・・ひずみ
ゲージ、ｐ・・・荷重信号、δ・・・引算後変位信号、
ａ・・・亀裂長さ。Figure 1 is a circuit diagram of a conventional unloading elastic compliance measuring device, Figure 2 is a crack length calibration curve diagram based on the unloading elastic compliance method, and Figure 3 is an implementation of the automatic fatigue crack length measuring device of the present invention. Example block diagram, Figure 4 is a load-displacement hysteresis diagram in a slit state (no crack), Figure 5 is a load-displacement hysteresis diagram after subtraction in a slit state, and Figure 6 is a diagram of the load-displacement hysteresis in a slit state. FIG. 7 is a diagram showing changes in load-displacement hysteresis after subtraction due to the crack closer phenomenon. 1... Field cell, 2... U link, 3, 4... Pin, 5... U link, 6... Testing machine actuator, 7... Unloading elastic compliance measuring device, 8...・
・Potentiometer for adjusting the amount of subtraction, 9... Differential range setter, 10... First differentiator, 11... Second differentiator,
12... Crack length setting device, 13... Testing machine stop signal generator, 14... Analog divider, 15... Arithmetic device, 16... Fatigue crack length automatic measuring device, 17・・・
・Test piece, 18° 19... Rod, 20... Strain gauge, p... Load signal, δ... Displacement signal after subtraction,
a...Crack length.

Claims

[Scope of utility model registration request]

an unloading elastic compliance measuring device that inputs the load signal of the test load applied to the crack test specimen and the displacement signal of the test specimen;
A first differentiator that inputs the load signal output from this measuring device, a second differentiator that inputs the displacement signal after subtraction from the same measuring device, and a differential range setting that sets the differential range by inputting it to the first differentiator. An analog divider that inputs the output signal from the divider and performs division, and an arithmetic device that inputs the output signal of the divider and converts compliance into crack length. An automatic fatigue crack length measuring device featuring: