VORTEX CURRENT CALLIPER Russian patent published in 2011 - IPC G01B7/06 G01N27/90 

FIELD: machine building.

SUBSTANCE: vortex current calliper consists of auto generator, of two vortex current converters in form of two cylinder coils, of differential transformer as comparing device, and of two cascade connected keys. An output of the auto-generator is connected to the cascade connected keys controlled with a paraphase signal from the auto-generator. Two parallel connected identical coils of similar inductance L are connected to the keys. Identical condensers of capacity C ensuring matching of proper frequency of inductive-capacity circuits with frequency of the auto-generator are coupled in series to each coil. Both parallel circuits LC are connected to the differential transformer. Tubes out of similar material are inserted inside the coils as cores. One of the tubes is a reference one and has specified thickness of a wall. The second tube is the object of measurement. Frequency of the auto-generator should facilitate such depth of penetration of an electro-magnetic wave into material of the tubes, which is not less, than thickness of the wall.

EFFECT: increased accuracy of measurement.

2 dwg