DEVICE FOR MONITORING LIMITING LEVEL IN CONTAINER Russian patent published in 2010 - IPC G01F23/296 

FIELD: physics.

SUBSTANCE: device has a mechanical oscillatory system placed on the mark of the given filling level. Voltage from an external generator is applied across exciting transducers. Piezoelectric elements (11, 12) are deformed owing to piezoelectric effect. A membrane (3) and bars (1) are displaced through a fastening screw (4 9) and an extra metal ring (6), resting on connecting piece (5). Resonance frequency of the system: bar (1) and membrane (3) falls according to immersion of the bar into viscous medium. Piezoelectric elements (13, 14) of the feedback transducer serve for converting oscillations of the mechanical system into an electrical signal and controlling operation of the generator. When filling or evacuating the container, substance reaches places where the device is fitted and natural oscillation frequency thereof varies according to immersion or drying of the bar. Change in resonance frequency of the system is a measure of the level of the liquid at the point where the device for monitoring the limiting level is located.

EFFECT: high efficiency of the device owing to high amplitude of oscillation of the bar and electric output signal of the feedback transducer, which widens its field of use in more viscous and non-homogeneous granular media.

2 cl, 7 dwg