Method and apparatus for processing electrical signals and a stress wave sensor
US5176032A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 2, 1992 |
| Grant date | Jan 5, 1993 |
| Priority date | — |
| Expiry date | Jun 2, 2012 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T10/40
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An apparatus for processing electrical signals corresponding to acoustic emissions produced in a machine or process comprises a transducer acoustically coupled to the machine or process, which detects the acoustic emissions and converts them into an output signal. The output signal is amplified by an amplifier, rectified and enveloped by an enveloper having a short time constant to produce an electrical signal. An enveloper having a long time constant, measures the mean level of the electrical signal. A DC component remover removes the DC component from the electrical signal and an enveloper, having a long time constant, measures the mean level of the rectified AC component of the electrical signal. A processor having a low sampling rate, measures a power of the ratio between the mean level of the rectified AC component of the electrical signal and the mean level of the electrical signal. The apparatus is self compensating for variations in the machine operating condition or transducer sensitivity and is relatively cheap to manufacture.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.