US 11,817,755 B2
Axisymmetric linear resonant actuators
Brett W. Degner, Menlo Park, CA (US); Brenton A. Baugh, Los Altos Hills, CA (US); Shingo Yoneoka, Saratoga, CA (US); and Songsheng Zhou, San Jose, CA (US)
Assigned to Apple Inc., Cupertino, CA (US)
Filed by Apple Inc., Cupertino, CA (US)
Filed on Jun. 1, 2021, as Appl. No. 17/336,074.
Prior Publication US 2022/0385160 A1, Dec. 1, 2022
Int. Cl. H02K 33/18 (2006.01); H02K 1/34 (2006.01); G06F 3/01 (2006.01); G06F 3/0354 (2013.01)
CPC H02K 33/18 (2013.01) [H02K 1/34 (2013.01); G06F 3/016 (2013.01); G06F 3/03545 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A linear resonant actuator, comprising:
a ferritic tube having an axis extending from a first end of the ferritic tube to a second end of the ferritic tube;
a movable mass having a set of magnet sections disposed along the axis;
a first flexure mechanically coupling a first end of the movable mass to the ferritic tube;
a second flexure mechanically coupling a second end of the movable mass to the ferritic tube;
a set of one or more electric coils attached to the ferritic tube and extending around the movable mass, between the ferritic tube and the movable mass; wherein,
each magnet section in the set of magnet sections has magnetic poles disposed at different positions along the axis;
like magnetic poles of adjacent magnetic sections face each other; and
the first flexure and the second flexure suspend the movable mass within the ferritic tube and allow movement of the movable mass along the axis.