BENDING MOMENT SENSOR FOR VORTEX FLOWMETERS Russian patent published in 2019 - IPC G01F1/32 

FIELD: measuring equipment.

SUBSTANCE: invention relates to liquid, gas or steam vortex flowmeters, in particular, to bending moment sensors used and intended for recording frequency of vortices formed in flow of liquid, gas or vapor behind streaming body. In a bending moment sensor for liquid or gas vortex flowmeters, having a hollow cylindrical metal housing, ending on one side with a wedge-shaped wing, and on the other side with a pressure-tight input with a coaxial cable having a screen and central conductors connected to the piezoelectric unit located inside the housing, according to the invention, the piezoelectric assembly is composed of two spatially spaced apart metallized piezoelectric plates on the planes, which are rigidly fixed to each other on the side of narrow face ends by means of annular and H-shaped retainers, to metalized surfaces of each of plates are connected conductors of coaxial cable, wherein sum of length of plates and thickness of ring coincides with depth of cylindrical hollow part of metal housing, and distance between external metallized surfaces of plates, width of plates, clearance between inner surface of metal housing of sensor and edge of external metallized surface of piezoelectric plate are selected from certain conditions. Metal-coated surfaces of piezoelectric plates on the side of annular retainer can be connected either to screen conductor of coaxial cable or central conductor. Screen conductor of the coaxial cable can be additionally connected to the housing.

EFFECT: high sensitivity of the sensor, low level of minimum measured velocities and, consequently, low level of minimum measured flow rates.

6 cl, 3 dwg, 2 tbl