US 12,452,605 B2
Speaker
Hiroki Toita, Fukushima (JP); and Yusuke Yoshida, Fukushima (JP)
Assigned to ALPS ALPINE CO., LTD., Tokyo (JP)
Filed by ALPS ALPINE CO., LTD., Tokyo (JP)
Filed on Feb. 9, 2023, as Appl. No. 18/107,756.
Claims priority of application No. 2022-024790 (JP), filed on Feb. 21, 2022.
Prior Publication US 2023/0269540 A1, Aug. 24, 2023
Int. Cl. H04R 9/06 (2006.01); H04R 7/12 (2006.01); H04R 9/02 (2006.01); H04R 9/04 (2006.01)
CPC H04R 9/046 (2013.01) [H04R 7/12 (2013.01); H04R 9/025 (2013.01); H04R 9/06 (2013.01)] 16 Claims
OG exemplary drawing
 
1. A speaker diaphragm configured to be fixed to a bobbin around which is wound a voice coil, the speaker diaphragm comprising:
a base on one side along a reference line extending in a sounding direction and an end on another side, the base including a hole configured to receive the bobbin,
wherein, when projected to a plane perpendicular to the reference line, the hole has a perfectly circular shape centered on the reference line, and the outer peripheral end is larger in dimension along a major axis than along a minor axis perpendicular to the major axis,
wherein the speaker diaphragm includes a perfectly circular cross-sectional area in a predetermined height range from an intermediate portion between the base and the end to the base, wherein, in the predetermined height range, the perfectly circular cross-sectional area is perfectly circular in cross section taken along a plane perpendicular to the reference line,
wherein, in a cross section containing the reference line, an outer surface of the perfectly circular cross-sectional area has an arc shape having a center of curvature outside the speaker diaphragm, wherein the arc shape has a constant radius around a whole circumference in a direction of rotation about the reference line,
wherein the speaker diaphragm includes an expanded area nearer to the end than the perfectly circular cross-sectional area,
wherein, in a cross section containing the reference line, an outer surface of the expanded area has an arc shape having a center of curvature outside the speaker diaphragm, wherein a radius of the arc shape in the major axis is larger than the radius in the minor axis, wherein the radius in the major axis and the radius in the minor axis are larger than the radius of the perfectly circular cross-sectional area,
wherein the speaker diaphragm includes an intermediate area between the perfectly circular cross-sectional area and the expanded area, and
wherein, in a cross section containing the reference line, an outer surface of the intermediate area has an arc shape having a center of curvature outside the speaker diaphragm, wherein, in the intermediate area, a radius of the arc shape is constant around a whole circumference in a direction of rotation about the reference line, and the radius of the intermediate area is smaller than the radius of the perfectly circular cross-sectional area.