Method and device for transmitting and receiving electro-magnetic ultrasound
US4420978A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 7, 1981 |
| Grant date | Dec 20, 1983 |
| Priority date | — |
| Expiry date | Apr 7, 2001 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2291/02827
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method at the transmission and reception of electromagnetically generated and received pulses of ultrasound, especially at non-destructive testing of electrically conductive material. The method comprises the steps of in a transmitter generating a first magnetic field by means of a first coil and a magnet core and supplying a transmitter coil located in the first magnetic field with a transmission pulse of ultrasonic frequency, and in a receiver generating a second magnetic field by means of a second coil and magnet core and by means of a receiver coil located in the second magnetic field receiving a signal originating from said transmitted pulse. When testing in this way nonmagnetic material, the signal/noise ratio is low. The noise partially originates from generated ultrasound affecting the transmitter and receiver magnets. According to the invention, a first transmission pulse is caused to be transmitted and received while the current in said first coil (1) and said second coil (2) has the same or different direction, whereafter the received signal is stored in a memory (8) intended therefor, whereafter a second transmission pulse is caused to be transmitted and received whil…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.