发明名称 |
Method and device for the non-destructive and contactless detection of flaws in a test piece moved relative to a probe |
摘要 |
Method for nondestructive and contact-free detection of faults in a test specimen which is moved relative to a probe that detects a periodic electrical signal having a carrier oscillation whose amplitude and/or phase is/are modulated by any fault in the test specimen. The probe signal is filtered and sampled by a triggerablie A/D converter stage to obtain a demodulated digital measurement signal which is filtered using a digital frequency-selective adjustable second filter unit to obtain a useful signal which is evaluated to detect a fault in the test specimen. The A/D converter stage is triggered at a fraction of the frequency of the carrier oscillation selected as a function of the fault frequency obtained as the quotient of the relative speed between the test specimen and the probe and the effective width of the probe, and the frequency-selective second filter unit is adjusted as a function of the fault frequency.
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申请公布号 |
US2007080681(A1) |
申请公布日期 |
2007.04.12 |
申请号 |
US20050595899 |
申请日期 |
2005.07.18 |
申请人 |
PRUEFTECNIK DIETER BUSCH AG |
发明人 |
HOELZL ROLAND;HERMANN MICHAEL |
分类号 |
G01N27/82 |
主分类号 |
G01N27/82 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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