DEVICE FOR MEASUREMENT OF LIQUID DENSITY Russian patent published in 2002 - IPC

FIELD: continuous measurement of density of petroleum products directly in reservoirs of petrol stations and oil tank centers. SUBSTANCE: method consists in converting motion of float into electrical signal. Used as converter is two-circuit self-excited oscillator whose one oscillatory circuit is just coaxial line vertically immersed in liquid under test together with float embracing it on the outside; external circular permanent magnet is secured on said float; when float is set in motion due to change in density of liquid under test, circular permanent magnet is also set in motion; this magnet is arranged inside coaxial line and is connected with shorting plunger made from non-magnetic alloy; it has sliding galvanic contact with both tubes of coaxial line. While moving, plunger shorts coaxial line at different points, thus changing its active length and consequently frequency of signal generated by oscillator depending on density of liquid. EFFECT: enhanced accuracy of measurements. 1 dwg