Low frequency broad band ultrasonic transducers
US9142752B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 30, 2013 |
| Grant date | Sep 22, 2015 |
| Priority date | — |
| Expiry date | Dec 24, 2033 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG10K11/002
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Low frequency pulse-echo ultrasonic transducers are provided especially suited for use in downhole cement bond evaluation, but usable for various applications. One frequency pulse-echo ultrasonic transducer comprises a transducer stack having alternating layers of a piezoceramic element and an ultrasonic attenuating element that is preferably acoustic impedance matched to the piezoceramic elements in order to reduce the Q of the transducer stack. Another low frequency pulse-echo ultrasonic transducer comprises an assembly having the present transducer stack disposed on an acoustic attenuating backing and a front face. Yet another low frequency pulse-echo ultrasonic transducer comprises a transducer composite made from a lead metaniobate. Still another frequency pulse-echo ultrasonic transducer comprises a composite stack. A further low frequency pulse-echo ultrasonic transducer comprises a composite stack, wherein multiple drive elements allow driving individual elements at different times. The transducers may be driven in a multiple-pulse time delayed manner.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.