LIQUID GAUGE Russian patent published in 2014 - IPC G01L7/18 

FIELD: measurement equipment.

SUBSTANCE: liquid gauge is proposed, comprising a U-shaped tube filled with liquid, an inlet elbow of which is connected with an air flow, and serially connected a generator of a probing signal, a receiver of an information signal, a solving unit and an indicator unit, differing by the fact that the solving unit is made in the form of an ADC, between the generator output and the receiver input there is an impedance dipole connected, to the second output of which also the upper end of one of two parallel electrodes of the impedance sensor is connected, the upper end of the second electrode of the impedance sensor is connected with an earth bus, the lower ends of the specified electrodes are lowered below the liquid level in a control elbow of the liquid gauge, and between the outlet of the receiver and the inlet of the solving unit there is a unit of compensation of a receiver's output signal constant. Besides, the unit of compensation of the receiver's output signal constant is made in the form of a galvanic element, the receiver is made in the form of serially connected a semiconductor diode and a low pass filter (LPF), the generator signal frequency is selected in the range of 103-105 Hz, besides, compensation of the receiver's output signal constant is provided through tuning of amplitude and/or frequency of the generator signal, or tuning of impedance of the impedance dipole, or tuning of the EMF, generated by the unit of compensation of the receiver's output signal constant. Besides, the impedance dipole is made in the form of a resistor or in the form of a capacitor. Besides, electrodes are installed in the inclined elbow in parallel to its longitudinal axis or in the vertical elbow as inclined towards its longitudinal axis. Besides, one of knees of the U-shaped tube filled with liquid serves as both the inlet and the control elbow. Besides, the impedance dipole is made in the form of a capacitor, the gauge liquid is selected as non-conducting with density less than in water, and electrodes are made in the form of plane-parallel plates. This provides for the above technical result.

EFFECT: increased dynamic range of measured physical values, simplicity of implementation, higher reliability and economic efficiency of a device, functional flexibility of a device, high noise immunity of a device to pulse noise together with its high sensitivity.

15 cl, 6 dwg