04264788 is referenced by 32 patents and cites 16 patents.

This invention relates to damping pads and accoustical horns for use with transducer assemblies. The problems of proximity detection ranges, subfreezing operating temperature ranges, ringing and backwave reflection are addressed. In a preferred embodiment of an ultrasonic level control indicator using a piezoelectric transducer, a resilient, compressible sound absorbing damping material (like polyurethane pads) is compressed against the transducer vibrating member to decrease ringing and backwave effects. An acoustical horn assembly with a tapered opening is positioned adjacent the transducer to improve the signal.

Title
Damped ultrasonic detection unit
Application Number
6/8170
Publication Number
4264788
Application Date
January 31, 1979
Publication Date
April 28, 1981
Inventor
Larry P Kahhan
Sicklerville
NJ, US
John F Keidel
Blue Bell
PA, US
Agent
Charles H Lindrooth
Assignee
Princo Instruments
PA, US
IPC
H04R 17/00
H01L 41/10
G01F 23/28
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