Acoustic pycnometer
AssigneeThe Dow Chemical Company
InventorBinneg Y. Lao
Life of this patent
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Abstract
An improved pycnometer in which the sample whose volume to be measured is put in a closed chamber to which an electro-mechanical transducer is coupled. The transducer is excited at a constant frequency. The change in impedance of the transducer is then read as a function of the volume of the sample.
Claims4
Pycnometer apparatus comprising an enclosable chamber for receiving a sample whose volume is to be measured, an electro-acoustical transducer coupled to the interior of said chamber, electronic signal generator means for electrically energizing said transducer at a predetermined frequency having a wave length at least four times the longest dimension of said chamber, electrical bridge circuit means coupled between said means for electrically energizing and said electro-mechanical transducer, said bridge circuit including means for nulling the signal across said bridge circuit when said chamber is empty, and means for reading the signal across said bridge when a sample is disposed in said chamber, the magnitude of said signal being a function of the volume of the sample.
Dependencies are inferred from the claim text.