Microprocessor based new technique for measuring pneumatic pressure using optocoupler controlled vibrating were transducer

IEEE;The Society of Instrument and Control Engineers, Japan Proceedings of the 1994 IEEE Instrumentation and Measurement Technology Conference. Part 2 (of 3) --10 May 1994 through 12 May 1994 -- Hamamatsu, Jpn -- A new and sensitive pneumatic pressure measuring device is proposed. The sensor consists of a diaphragm and a string fixed inside a hollow cylinder attached to a pneumatic medium. While one side of the diaphragm is exposed to pneumatic pressure, the string is stretched on the other side. With the use of a microprocessor, the string is periodically excited through an electromagnetand the vibrating frequency is measured from the signal obtained at an optocoupler. The frequency is calibrated to indicate the pressure.