US 12,340,927 B2
Detection of magnetic pulse and orientation when magnetizing
Jesper Kirt, Skibby (DK); Bo Justesen, Ringsted (DK); and Tanja Lykke Petersen, Regstrup (DK)
Assigned to Unomedical A/S, Lejre (DK)
Filed by UNOMEDICAL A/S, Lejre (DK)
Filed on Apr. 8, 2021, as Appl. No. 17/225,649.
Application 17/225,649 is a continuation of application No. PCT/EP2021/059240, filed on Apr. 8, 2021.
Claims priority of provisional application 63/007,469, filed on Apr. 9, 2020.
Prior Publication US 2021/0319940 A1, Oct. 14, 2021
Int. Cl. H01H 47/00 (2006.01); G01R 33/02 (2006.01); H01F 13/00 (2006.01)
CPC H01F 13/003 (2013.01) [G01R 33/02 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A magnetizing pulse detector that detects magnetizing pulses produced by a magnetizing coil; the magnetizing pulse detector comprising:
a measuring coil configured to generate a measuring pulse in response to a magnetizing pulse produced by the magnetizing coil;
a measuring pulse detection circuit configured to generate a detection signal based on the measuring pulse generated by the measuring coil; and
a duration extension circuit configured to generate an extended detection signal based on the detection signal generated by the measuring pulse detection circuit;
a first measuring pulse smoothing portion configured to smooth oscillations in the measuring pulse;
a second measuring pulse smoothing portion configured to smooth oscillations in the measuring pulse; and
a steering portion configured to direct a negative polarity measuring pulse to the first measuring pulse smoothing portion, and to direct a positive polarity measuring pulse to the second measuring pulse smoothing portion;
wherein the measuring pulse detection circuit comprises a plurality of Zener diodes connected in parallel to one another and connected in parallel with the measuring coil;
wherein the duration extension circuit is configured to trigger only when the detection signal exceeds a pulse threshold that indicates the magnetizing pulse produced by the magnetizing coil was sufficient to successfully magnetize a specimen and to remain triggered for a duration of a holding function of the duration extension circuit;
wherein the first measuring pulse smoothing portion generates a negative polarity detection signal when the negative polarity measuring pulse is directed to the first measuring pulse smoothing portion, and the second measuring pulse smoothing portion generates a positive polarity detection signal when the positive polarity measuring pulse is directed to the second measuring pulse smoothing portion;
wherein the duration extension circuit comprises a negative pulse detection circuit configured to trigger based on the negative polarity detection signal and a positive pulse detection circuit configured to trigger based on the positive polarity detection signal;
wherein the negative pulse detection circuit is configured to trigger only when the negative polarity detection signal exceeds a negative pulse threshold that indicates the magnetizing pulse produced by the magnetizing coil was sufficient to successfully magnetize a specimen with negative polarity; and
the positive pulse detection circuit is configured to trigger only when the positive polarity detection signal exceeds a positive pulse threshold that indicates the magnetizing pulse produced by the magnetizing coil was sufficient to successfully magnetize the specimen with positive polarity.