Device and method for locating ferromagnetic hidden objects in a nonferromagnetic environment and for determining their dilatation

摘要

A permanent magnet (2) generates static magnetic field with a bias field strength larger than the earth's magnetic field strength. The permanent magnet is adjustably and symmetrically arranged with the magnetic field sensor (1), such that the gap between the magnetic field sensor and permanent magnet is twice as large as the diameter of the permanent magnet. A preamplifier (3) and the evaluation unit are arranged after the permanent magnet. The localization device has a measuring unit provided for the path covered by a sensor head (I) which is electrically connected to an evaluation unit (III) through an integrated line unit. A power supply is provided for the evaluation unit. A threshold setting unit, a comparator, virtual logarithmic amplifiers, and optical or acoustic display are provided with the evaluation unit. An Independent claim is also included for the localization and determination of expansion of invisible ferromagnetic body in a non-ferromagnetic environment.