- Email: [email protected]
Acoustic detection devices
tube is less than one-half wavelength highest frequency to be propagated.
of the
Acoustic detection finders: monostable circuits Freid Krupp GmbH UK patent 1269566 (1972) filed 12 July 1968 An arrangement for determining the direction of incidence of sound waves within a relatively broad angular region comprises: an array of transducers whose outputs are combined to form a plurality of relatively narrow beam patterns covering different adjacent sectors of the region; a device for periodically scanning received signals of all the sectors; a cathode ray oscilloscope; and a device for determining the incidence direction within any sector from the phase or travel-time difference between received signals in two beam patterns associated with that sector. Ultrasonic transducers: ultrasonic lenses F. Hoffmann La Roche & Co AG UK patent 1269869 (1972) filed 5 June 1969 An ultrasonic transducer assembly which can be used for investigating human arterial wall motion using the doppler effect, has an elongate preset curved printed circuit board supporting ultrasonic transducer units along its longitudinal axis. I
Transmission of ultrasound through the larynx as a means of determining vocalfold activity Hamlet, S. L., Reid, .I. M. Bio-Medical Engineering Vol BME 19 No 7 (January 1972) pp 34-37 A method of determining vocal-fold closure using continuous-wave ultrasound through the larynx is described. A frequency of 3.2 MHz and an applied acoustic power of less than 1 mV cm-’ is used. Phvsiological interpretation of received signals is discussed in terms of glottal closure, vocal-fold thickness, vocal-fold vibratory pattern, and thyroid cartilage ossification. Suggestions are offered for choice and arrangement of transducers for this application. Sonar (sound navigation and ranging) 1. Introduction Reith, B. C. Ingenieur Vol 83 No 5 1 (December 19 7 1) pp 180-183 (In Dutch) Sonar (sound navigation and ranging) II. Transducers foiactive sonar - -Rijnja, H. A. J. Ingenieur Vo183 No 51 (December 1971) pp 183-188 (In Dutch)
_
Ultrasonic flaw detection Allegheny Ludlum Industries Inc UK patent 1269845 (1972) filed 22 November 1968 A flaw detector in which pulsed ultrasound echoes from boundaries transverse to the scanning beam are blanked out, utilizes an electron recording beam in a storage oscilloscope.
Sonar devices: sonar transducers Sparton Corp UK patent 1269751 (1972) tiled 14 April 1969 An acoustically sensitive transducer comprises a piezoelectric cylinder carrying two sets of electrodes, one set provides omnidirectional voltages and the other set orthogonal directional bearing related voltages.
Ultrasonic inspection devices International Research & Development Co Ltd UK patent 1270387 (1972) filed 7 June 1968
Acoustic detection devices National Research Development Corp UK patent 1270245 (1972) filed 11 June 1968 An apparatus for counting fish passing through a water channel beams ultrasound to illuminate the channel in two crosssectional planes, and counts only if echoes are detected from both planes.
192
MISCELLANEOUS
Improved depthfinder display presentation bv use of MS1 Brede, R. Electroteknisk Tidsskrift Vol 84 No 20 (November 1971) pp 19-20 (In Norwegian) Equipment for the fine welding of electrical and electronic components Rub, F. Electrotechnik Vol 53 No 19 (October 1971) pp 20-24 (In German) An ultrasonic-microwelding method welding small synthetic components described. Diagnostic sonar Sabbagha, R. E. Instrumentation Technology (December 1971) pp 40-43
for is
Vol 18 No 12
Ultrasonics for ultra-clean surfaces Industrial Finishing and Surface Coatings Vo123 No 282 (December 1971) pp 26-28 Ultrasonic pressure gauge for static pressure Hoechli, U. T., Mueller, F., Nievergelt, H. IBM Technical Disclosure Bulletin Vol 14 No 5 (October 1971) pp 1629-1630 An ultrasonic pressure gauge will record static pressure between 1 and lo4 k? cm-’ with an accuracy of 0.17cfrom a few degrees Kelvin up to about 1000 K. Microstructure detection with the aid of ultrasound Wegel, G. Feinger’ate-Technik Vol 20 No 12 (December 1971) pp 563-566 (In German) A technique for determining the microstructure in cast iron from measurement of the speed of ultrasound in the material is described. A clear distinction can be made
between spheroidal and lame&r graphite structure. Advantages of the method include the facility for serial testing with negligible time delays. Automation of ultrasonic and eddy current methods Gunnell, R. A. Testing, Instruments & Controls Vo18 No 11 (1971) pp 13-17 Bat’s sonar simulator Escudie, B., Dziedzic, A., Barreault, G. Revue d’Acoustique Vol 5 No 18 (1972) pp 26-30 The study of bat’s sonar using spectral analysis and signal processing requires a generator emitting signals similar to those emitted by bats. A wide-band frequency modulated oscillator provides many of the emitted waveforms used by vespertillions and other bats. The experiments prove that the signals are similar to those recorded in nature. Proposals for the measurement of volume flow by ultrasonic methods Fitzhugh, H. A., Twidle, G. G., Richardson, J. R. National Physical Laboratory Report NPL-MS No 3-71 (October 1971) 4 pp A method of measuring the rate of volume flow in an air duct is proposed which depends on the downstream convection of an ultrasonic beam projected across the flow. The device requires no calibration, has a high frequency response and does not obstruct the flow. A method for digital measurement of attenuation Gavenda, J. D. Review of Scientific Instruments Vol 42 No 12 (December 1971) pp 1881-1882 Surface-wave amplifier with improved geometry Adler, R. Electronics Letters Vol 8 No 3 (February 1972) pp 65-66 A surface-wave amplifier is proposed in which an array of transverse conducting bars couples a narrow semi-conductor to a broad region of piezoelectric substrate. Ultrasonic determination of liver and spleen volumes Kardel, T., Holm, H. H., Norby Rasmussen, S., Mortensen, T. Scandinavian Clinical Laboratory Investigations Vol 20 No 2 (1971) pp 123-128 Nonlinear materials for acoustic surfacewave convolver Lim, T. C., Kraut, E. A., Thompson, R. B. Applied Physics Letters Vol 20 No 3 (February 197 2) pp 1277 129 Acoustic surface-wave convolution by nonlinear mixing has been observed in cubic, hexagonal and trigonal crystals. The magnitudes of the phenomenological nonlinear surface-wave coupling constants are tabulated and compared with the linear electromechanical coupling factor 2 @Y/v). It has been found that the basal plane of pzt-8 has a larger nonlinear coupling constant that that of the commonly used y-cut, z-propogating LiNbOs.
ULTRASONICS.
JULY 1972
of the
Acoustic detection finders: monostable circuits Freid Krupp GmbH UK patent 1269566 (1972) filed 12 July 1968 An arrangement for determining the direction of incidence of sound waves within a relatively broad angular region comprises: an array of transducers whose outputs are combined to form a plurality of relatively narrow beam patterns covering different adjacent sectors of the region; a device for periodically scanning received signals of all the sectors; a cathode ray oscilloscope; and a device for determining the incidence direction within any sector from the phase or travel-time difference between received signals in two beam patterns associated with that sector. Ultrasonic transducers: ultrasonic lenses F. Hoffmann La Roche & Co AG UK patent 1269869 (1972) filed 5 June 1969 An ultrasonic transducer assembly which can be used for investigating human arterial wall motion using the doppler effect, has an elongate preset curved printed circuit board supporting ultrasonic transducer units along its longitudinal axis. I
Transmission of ultrasound through the larynx as a means of determining vocalfold activity Hamlet, S. L., Reid, .I. M. Bio-Medical Engineering Vol BME 19 No 7 (January 1972) pp 34-37 A method of determining vocal-fold closure using continuous-wave ultrasound through the larynx is described. A frequency of 3.2 MHz and an applied acoustic power of less than 1 mV cm-’ is used. Phvsiological interpretation of received signals is discussed in terms of glottal closure, vocal-fold thickness, vocal-fold vibratory pattern, and thyroid cartilage ossification. Suggestions are offered for choice and arrangement of transducers for this application. Sonar (sound navigation and ranging) 1. Introduction Reith, B. C. Ingenieur Vol 83 No 5 1 (December 19 7 1) pp 180-183 (In Dutch) Sonar (sound navigation and ranging) II. Transducers foiactive sonar - -Rijnja, H. A. J. Ingenieur Vo183 No 51 (December 1971) pp 183-188 (In Dutch)
_
Ultrasonic flaw detection Allegheny Ludlum Industries Inc UK patent 1269845 (1972) filed 22 November 1968 A flaw detector in which pulsed ultrasound echoes from boundaries transverse to the scanning beam are blanked out, utilizes an electron recording beam in a storage oscilloscope.
Sonar devices: sonar transducers Sparton Corp UK patent 1269751 (1972) tiled 14 April 1969 An acoustically sensitive transducer comprises a piezoelectric cylinder carrying two sets of electrodes, one set provides omnidirectional voltages and the other set orthogonal directional bearing related voltages.
Ultrasonic inspection devices International Research & Development Co Ltd UK patent 1270387 (1972) filed 7 June 1968
Acoustic detection devices National Research Development Corp UK patent 1270245 (1972) filed 11 June 1968 An apparatus for counting fish passing through a water channel beams ultrasound to illuminate the channel in two crosssectional planes, and counts only if echoes are detected from both planes.
192
MISCELLANEOUS
Improved depthfinder display presentation bv use of MS1 Brede, R. Electroteknisk Tidsskrift Vol 84 No 20 (November 1971) pp 19-20 (In Norwegian) Equipment for the fine welding of electrical and electronic components Rub, F. Electrotechnik Vol 53 No 19 (October 1971) pp 20-24 (In German) An ultrasonic-microwelding method welding small synthetic components described. Diagnostic sonar Sabbagha, R. E. Instrumentation Technology (December 1971) pp 40-43
for is
Vol 18 No 12
Ultrasonics for ultra-clean surfaces Industrial Finishing and Surface Coatings Vo123 No 282 (December 1971) pp 26-28 Ultrasonic pressure gauge for static pressure Hoechli, U. T., Mueller, F., Nievergelt, H. IBM Technical Disclosure Bulletin Vol 14 No 5 (October 1971) pp 1629-1630 An ultrasonic pressure gauge will record static pressure between 1 and lo4 k? cm-’ with an accuracy of 0.17cfrom a few degrees Kelvin up to about 1000 K. Microstructure detection with the aid of ultrasound Wegel, G. Feinger’ate-Technik Vol 20 No 12 (December 1971) pp 563-566 (In German) A technique for determining the microstructure in cast iron from measurement of the speed of ultrasound in the material is described. A clear distinction can be made
between spheroidal and lame&r graphite structure. Advantages of the method include the facility for serial testing with negligible time delays. Automation of ultrasonic and eddy current methods Gunnell, R. A. Testing, Instruments & Controls Vo18 No 11 (1971) pp 13-17 Bat’s sonar simulator Escudie, B., Dziedzic, A., Barreault, G. Revue d’Acoustique Vol 5 No 18 (1972) pp 26-30 The study of bat’s sonar using spectral analysis and signal processing requires a generator emitting signals similar to those emitted by bats. A wide-band frequency modulated oscillator provides many of the emitted waveforms used by vespertillions and other bats. The experiments prove that the signals are similar to those recorded in nature. Proposals for the measurement of volume flow by ultrasonic methods Fitzhugh, H. A., Twidle, G. G., Richardson, J. R. National Physical Laboratory Report NPL-MS No 3-71 (October 1971) 4 pp A method of measuring the rate of volume flow in an air duct is proposed which depends on the downstream convection of an ultrasonic beam projected across the flow. The device requires no calibration, has a high frequency response and does not obstruct the flow. A method for digital measurement of attenuation Gavenda, J. D. Review of Scientific Instruments Vol 42 No 12 (December 1971) pp 1881-1882 Surface-wave amplifier with improved geometry Adler, R. Electronics Letters Vol 8 No 3 (February 1972) pp 65-66 A surface-wave amplifier is proposed in which an array of transverse conducting bars couples a narrow semi-conductor to a broad region of piezoelectric substrate. Ultrasonic determination of liver and spleen volumes Kardel, T., Holm, H. H., Norby Rasmussen, S., Mortensen, T. Scandinavian Clinical Laboratory Investigations Vol 20 No 2 (1971) pp 123-128 Nonlinear materials for acoustic surfacewave convolver Lim, T. C., Kraut, E. A., Thompson, R. B. Applied Physics Letters Vol 20 No 3 (February 197 2) pp 1277 129 Acoustic surface-wave convolution by nonlinear mixing has been observed in cubic, hexagonal and trigonal crystals. The magnitudes of the phenomenological nonlinear surface-wave coupling constants are tabulated and compared with the linear electromechanical coupling factor 2 @Y/v). It has been found that the basal plane of pzt-8 has a larger nonlinear coupling constant that that of the commonly used y-cut, z-propogating LiNbOs.
ULTRASONICS.
JULY 1972