Detection of damped sine waves in a magnestostrictive displacement transducer using pretrigger and detection thresholds of opposite polarity
US5212444A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 31, 1991 |
| Grant date | May 18, 1993 |
| Priority date | — |
| Expiry date | Jul 31, 2011 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01F23/2963
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A damped sine wave detector for detecting the response of a magnetostrictive displacement transducer. A pretrigger comparator compares the signal to a predetermined negative threshold. A signal comparator compares the input signal to a predetermined positive threshold. The pretrigger comparator turns on a pretrigger flip-flop and starts a delay timer when the input signal falls below the predetermined negative threshold. The pretrigger flip-flop supplies the data input of a signal flip-flop. The signal flip-flop is clocked by the signal comparator when the input signal is above the predetermined positive threshold. The signal flip-flop turns on if clocked and the pretrigger flip-flop is on. The detector includes two timers for resetting the flip-flops. An inhibit timer resets both flip-flops upon expiration of an inhibit time longer than the maximum expected duration of the damped sine wave signal. A delay timer resets only the pretrigger flip-flop after a delay time greater than the maximum expected interval between when the damped sine wave falls below the predetermined negative threshold and when the damped sine wave rises above the predetermined positive threshold. Thus the cir…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.