USA as Represented by Secretary of the Navy

Lawrence M Brown

Reza Zoughi

John Mittleman

Robert DeNale

Nasser Nidal Qaddoumi

Timothy A Bigelow

An inventively enhanced near-field sensor includes circuitry which removes variation in standoff distance (of the sensor from the inspected object) as a factor in the inspection system readings. An original output voltage which varies linearly according to standoff distance is, modified and added to a counterbalancing output voltage which equivalently but oppositely varies linearly according to standoff distance, resulting in a constant output voltage regardless of standoff distance. For calibration purposes, a third output voltage can also be summed along with the modified output voltage and the counterbalancing output voltage. Since the effect of surface variation is nullified, the practitioner can more truly assess the interior physical condition of the inspected object, knowing that the object's surface roughess is rendered irrelevant.

Standoff distance variation compensator and equalizer

Field strength of an electromagnet is monitored at a threshold with a coupling coil positioned to monitor magnetic flux in a leg of an electromagnet. In the context of magnetic particle inspection for surface flaws (e.g. cracks) in ferromagnetic materials, sensing magnetic flux in a portion of a magnetic circuit including the material being inspected provides a continuous direct indication of whether or not the magnetic field strength produced is sufficient for reliable inspection to be performed. Since the magnetic flux in the electromagnet will be reduced with increases in reluctance of the magnetic circuit, the continuous monitoring of magnetic field strength also effectively monitors correct inspection technique by the magnetic particle inspection methodology.

Growing community of inventors

Manassas, VA, United States of America

Lawrence M Brown