초록 ▼

The magnetic marker strip is formed of a signal strip made from ferromagnetic material with a low coercive force onto which there is applied ferromagnetic material whose coercive force is distinctly higher than that of the material of the signal strip. The signal strip is relatively long as compared

The magnetic marker strip is formed of a signal strip made from ferromagnetic material with a low coercive force onto which there is applied ferromagnetic material whose coercive force is distinctly higher than that of the material of the signal strip. The signal strip is relatively long as compared with its width, and emits harmonic-containing signals in a first, unmagnetized state as a consequence of the magnetic field in the interrogation region and emits no harmonic-containing signal in a second state in this magnetic field. The ferromagnetic material with the larger coercive force is arranged in the form of a plurality of control elements at a spacing from one another on the signal strip, the width of the control elements being essentially equal to the width of the signal strip, and the control elements switching the signal strip into the first state when they are in a first, unmagnetized state, and switching the signal strip into the second state when they are in a second, magnetized state. The signal strip is cut to length from a tape made from an amorphous, ductile alloy that is virtually free from magnetostriction transversely to the longitudinal axis of the tape, and the tape has a flat B-H loop whose axis is parallel to the longitudinal axis of the band.

대표청구항 ▼

[ We claim:] [1.]1. A magnetic marker strip for generating a signal inside an interrogation zone in which a periodically varying magnetic field with a predetermined fundamental frequency is present, the magnetic marker strip comprising:a signal strip of a first ferromagnetic material having a low co

[ We claim:] [1.]1. A magnetic marker strip for generating a signal inside an interrogation zone in which a periodically varying magnetic field with a predetermined fundamental frequency is present, the magnetic marker strip comprising:a signal strip of a first ferromagnetic material having a low coercive field strength, said signal strip having a greater length than width, and emitting harmonic-containing signals in a first, unmagnetized state when exposed to a magnetic field in an interrogation zone and emitting substantially no harmonic-containing signal in a second state in the magnetic field;said signal strip being cut to length from a tape transversely to a longitudinal axis of the tape, said tape consisting of an amorphous, ductile alloy virtually free from magnetostriction, and having a flat B-H loop with an axis parallel to the longitudinal axis of the tape;a second ferromagnetic material applied on said signal strip and having a coercive field strength distinctly higher than the coercive field strength of said first ferromagnetic material of said signal strip; andsaid second ferromagnetic material being formed in a plurality of deactivating elements disposed at a spacing from one another on said signal strip, said deactivating elements having a width substantially equal to the width of said signal strip, and said deactivating elements switching said signal strip into the first state when said deactivating elements are in a first, unmagnetized state, and switching said signal strip into the second state when said deactivating elements are in a second, magnetized state.