High energy, low frequency, ultrasonic transducer
US6109109A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 19, 1998 |
| Grant date | Aug 29, 2000 |
| Priority date | — |
| Expiry date | Oct 19, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2291/2626
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A wide bandwidth, ultrasonic transducer to generate nondispersive, extensional, pulsed acoustic pressure waves into concrete reinforced rods and tendons. The wave propagation distance is limited to double the length of the rod. The transducer acoustic impedance is matched to the rod impedance for maximum transfer of acoustic energy. The efficiency of the transducer is approximately 60 percent, depending upon the type of active elements used in the transducer. The transducer input energy is, for example, approximately 1 mJ. Ultrasonic reflections will occur at points along the rod where there are changes of one percent of a wavelength in the rod diameter. A reduction in the rod diameter will reflect a phase reversed echo, as compared with the reflection from an incremental increase in diameter. Echo signal processing of the stored waveform permits a reconstruction of those echoes into an image of the rod. The ultrasonic transducer has use in the acoustic inspection of long (40+foot) architectural reinforcements and structural supporting members, such as in bridges and dams.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.