US 12,260,887 B1
Voice coil motor composite magnet assembly including low-coercivity magnetic material
Brandon Kaplan, Woodinville, WA (US)
Assigned to Western Digital Technologies, Inc., San Jose, CA (US)
Filed by Western Digital Technologies, Inc., San Jose, CA (US)
Filed on Sep. 27, 2023, as Appl. No. 18/373,957.
Int. Cl. G11B 5/55 (2006.01); G11B 5/48 (2006.01); H02K 1/02 (2006.01); H02K 15/03 (2006.01); H02K 41/035 (2006.01)
CPC G11B 5/5521 (2013.01) [G11B 5/4813 (2013.01); H02K 1/02 (2013.01); H02K 15/03 (2013.01); H02K 41/0354 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A voice coil motor (VCM) comprising:
a coil;
a first yoke having a coil-side facing the coil;
a first low-coercivity permanent magnet positioned between the coil and the coil-side of the first yoke and having a yoke-side facing the first yoke and a coil-side opposing the yoke-side;
a first high-coercivity permanent magnet adjoining the coil-side of the first low-coercivity permanent magnet;
a second yoke having a coil-side facing the coil;
a second low-coercivity permanent magnet positioned between the coil and the coil-side of the second yoke and having a yoke-side facing the second yoke and a coil-side opposing the yoke-side; and
a second high-coercivity permanent magnet adjoining the coil-side of the second low-coercivity permanent magnet.