EXPLOSION-PROOF FIBER-OPTIC LEVEL GAUGE Russian patent published in 2019 - IPC G01N21/35 G01F23/22 

FIELD: measuring equipment.

SUBSTANCE: invention relates to test and measurement equipment. Explosion-proof fiber-optic level gauge comprises an optical radiation source, an acoustooptical modulator connected to a high-frequency generator, a photodetector placed in a measurement information processing unit connected by an optical fiber to a fiber-optic sensor mounted on the monitored object. Output of the acoustooptical modulator is connected to the inlet port of the first circulator, the output port of the circulator is connected to the photodetector. Bidirectional port of the first circulator is connected by optical fiber to the bidirectional port of the second circulator, which is placed in the sensor, the output port of which is connected to the first pole of the first fiber-optic Y-splitter, made of single-mode optical fiber. Second pole of the first Y-splitter is connected to the input port of the third circulator, and the third pole of the first Y-splitter is connected to the second pole of the second Y-splitter. First pole of second Y-splitter is connected to inlet port of second circulator, and third pole of second Y-splitter is connected to output of third circulator, bidirectional port of which is arranged in focus of collimator lens, and the photodetector output is connected through an amplifier to a frequency detector, wherein the frequency of the high-frequency electronic generator varies according to a saw-tooth law.

EFFECT: high accuracy of measuring liquid level, simple design and high reliability of the level gauge.

1 cl, 2 dwg