| 摘要 |
<p>The device comprises a field winding (32) generating an alternating current in the material and enclosing the container (24) of said material, at least a magnetic field sensor (52, 54) in the zone delimited by the field winding, said sensor comprising a pair of magnetic transducers for detecting the partial differential, along an axis of the inductor, of the field radial component, means (68, 70) for demodulating signals supplied by the sensor, the demodulation taking place with a phase shift substantially of π/2 relative to the current powering the field winding, and means (72, 74, 76) for processing the signals supplied by the demodulating means and for supplying a signal indicating that the material has reached the sensor level.</p> |
