04244226 is referenced by 21 patents and cites 10 patents.

A distance measuring apparatus and a differential pressure transmitter utilizing the same having an ultrasonic element reflector mounted between a pair of ultrasonic transducers. The alternate operation of the ultrasonic transducers produces a pair of transducer energizing signals which are related to the relative separation of the reflector element from the transducers. In one embodiment, the reflector element is mounted within a closed pressure vessel divided internally by an ultrasonic reflector diaphragm with a pair of fluid inlet lines admitting respective pressurized fluids to corresponding sides of the reflector diaphragm. The ultrasonic transducer elements are mounted on the outside of the pressure vessel on an acoustical signal transmitting interface and are arranged to alternately supply an ultrasonic signal through the pressure vessel wall to the respective side of the diaphragm reflector while an analysis of the frequency of operation of each transducer is used to determine the differential pressure applied to the diaphragm.

Title
Distance measuring apparatus and a differential pressure transmitter utilizing the same
Application Number
6/81692
Publication Number
4244226
Application Date
October 4, 1979
Publication Date
January 13, 1981
Inventor
Douglas W Wilda
West Chester
PA, US
John L Searle
Camden
NJ, US
William F Newbold
Philadelphia
PA, US
Yoel Keiles
Havertown
PA, US
Norman F Green
Warrington
PA, US
Agent
Mitchell J Halista
Lockwood D Burton
Laurence J Marhoefer
Assignee
Honeywell
MN, US
IPC
G01L 11/00
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