FIBRE-OPTIC LEVEL GAUGE AND METHOD OF MAKING SAID GAUGE Russian patent published in 2010 - IPC G01F23/22 

FIELD: physics.

SUBSTANCE: fibre-optic level gauge has radiation sources and receivers, input and output optical fibres, circular bar with spherical segments. The radius of the bar satisfies the expression d_of≤R≤1.5d_of, where d_of is diametre of the optical fibre cladding. Each bar is lead to one input and one output fibre. The gauge also includes a pipe whose length is not less than the maximum value of the measured level of liquid with through holes on the lateral surface, inverted L-shaped housings consisting of rigidly joined hollow pipes, bushings and nose pieces in form of a cone. The holes in the top part of the hollow pipe are superposed with holes in the pipe and rods are fit into holes in the nose pieces. All optical fibres pass inside the pipe and through holes in the pipe to rods. The number of holes, inverted L-shaped housings and rods corresponds to the number of liquid level information retrieval points. The method of making the fibre-optic level gauge involves cutting 2n optical fibres, where n is number of controlled points of the liquid level. The fibres are joined into two bundles which are joined into one common bundle which is drawn through the pipe. Free ends of one of the input optical fibre and one output optical fibres, starting with the longest, are respectively drawn through holed in the pipe, starting with the lowest and moving upwards. The optical fibres are passed through hollow pipes of the housings and then glued in the bushing. The rods are glued in the nose pieces. The bushing is pressed by the nose pieces to the bottom end of the hollow pipes of housings and the pipes are welded at their junction points. The top parts of the housings are joined to the pipe. The bottom end of the pipe is closed by a plug. The free ends of input optical fibres are led to radiation sources and output optical fibres are led to radiation receivers.

EFFECT: possibility of monitoring several level values, reduced errors from wetting effect due to reduction of segment radius, working capacity in sever conditions of space-rocket engineering, high spark-, fire- and explosion safety.

2 cl, 3 dwg