US 12,207,049 B2
Headrest mounted loudspeaker for producing sound at base frequencies
David Corynen, Dendermonde (BE)
Assigned to PSS BELGIUM NV, Dendermonde (BE)
Appl. No. 17/999,147
Filed by PSS BELGIUM NV, Dendermonde (BE)
PCT Filed Jun. 2, 2021, PCT No. PCT/EP2021/064765
§ 371(c)(1), (2) Date Nov. 17, 2022,
PCT Pub. No. WO2021/249843, PCT Pub. Date Dec. 16, 2021.
Claims priority of application No. 2008724 (GB), filed on Jun. 9, 2020.
Prior Publication US 2023/0199377 A1, Jun. 22, 2023
Int. Cl. H04R 1/34 (2006.01); H04R 1/02 (2006.01); H04R 1/28 (2006.01); H04R 7/12 (2006.01); H04R 7/18 (2006.01)
CPC H04R 1/347 (2013.01) [H04R 1/025 (2013.01); H04R 1/288 (2013.01); H04R 7/12 (2013.01); H04R 7/18 (2013.01); H04R 2400/11 (2013.01); H04R 2499/13 (2013.01)] 14 Claims
OG exemplary drawing
 
1. An audio system comprising a dipole loudspeaker and a headrest;
the dipole loudspeaker includes: a diaphragm having a first radiating surface and a second radiating surface, wherein the first radiating surface and the second radiating surface are located on opposite faces of the diaphragm; a drive unit configured to move the diaphragm at bass frequencies such that the first and second radiating surfaces produce sound at bass frequencies, wherein the sound produced by the first radiating surface is in antiphase with sound produced by the second radiating surface; a loudspeaker frame, wherein the diaphragm is suspended from the loudspeaker frame via a primary suspension system; and
the headrest includes:
a main body assembly shaped to include a first opening configured to allow sound produced by the first radiating surface to propagate out of a first side of the headrest, and a second opening configured to allow sound produced by the second radiating surface to propagate out of a second side of the headrest, wherein the main body assembly includes a foam structure, wherein the foam structure is acoustically resistive; and
a projecting element formed of acoustically resistive foam, which extends between the foam structure of the headrest and the loudspeaker frame, wherein the projecting element provides:
a waveguide formation which is configured to direct sound produced by the first radiating surface out of the first opening, and to direct sound produced by the second radiating surface out of the second opening as a result of the projecting element and the loudspeaker frame combining to form an acoustic baffle; and
an attachment formation which is used to attach the loudspeaker frame to the headrest, wherein the attachment formation provides a secondary suspension system via which the loudspeaker frame is suspended.