US 11,943,578 B2
Loudspeaker enclosure with closeable port
Jakob Dyreby, Struer (DK)
Assigned to Bang & Olufsen A/S, Struer (DK)
Appl. No. 16/467,908
Filed by Bang & Olufsen A/S, Struer (DK)
PCT Filed Dec. 8, 2017, PCT No. PCT/DK2017/000022
§ 371(c)(1), (2) Date Jun. 7, 2019,
PCT Pub. No. WO2018/103798, PCT Pub. Date Jun. 14, 2018.
Claims priority of application No. PA 2016 00752 (DK), filed on Dec. 9, 2016; and application No. PA 2017 00065 (DK), filed on Feb. 2, 2017.
Prior Publication US 2019/0320257 A1, Oct. 17, 2019
Int. Cl. H04R 1/28 (2006.01); H04R 1/02 (2006.01)
CPC H04R 1/2826 (2013.01) [H04R 1/02 (2013.01); H04R 1/2892 (2013.01)] 19 Claims
OG exemplary drawing
 
1. A loudspeaker device comprising:
a loudspeaker unit comprising a diaphragm with a first and second surface and an enclosure in which the loudspeaker unit is mounted such that the first surface of the diaphragm is in acoustic communication with surroundings of the loudspeaker device; and
an internal cavity formed in the enclosure and being in acoustic communication with the surroundings of the loudspeaker device via an acoustic element;
wherein the second surface of the diaphragm is in acoustic communication with the internal cavity;
wherein the acoustic element is configured to be changed between an open state in which the acoustic element permits sound energy generated by the loudspeaker unit in the internal cavity to be emitted to the surroundings via the acoustic element and a closed state in which the acoustic element substantially prevents sound energy from entering the surroundings via the acoustic element,
wherein the acoustic element is configured to be changed between the open state and the closed state based on a threshold value of a sound pressure level that defines whether the acoustic element is to block or open acoustic communication from the internal cavity to the surroundings, wherein the threshold value is based on a diaphragm excursion limit of the loudspeaker unit such that when the sound pressure level generated by the loudspeaker device is above the threshold value, the acoustic element is configured to be in the open state to prevent non-linear distortion of an acoustic output of the loudspeaker device, and when the sound pressure level generated by the loudspeaker device is below the threshold value, the acoustic element is configured to be in the closed state.