Acoustic device having an electro-acoustic transducer mounted to a passive radiator diaphragm

Patent metadata

Field	Value
Publication number	US-10667039-B2
Application number	US-201916390121-A
Country	US
Kind code	B2
Filing date	Apr 22, 2019
Priority date	Mar 20, 2017
Publication date	May 26, 2020
Grant date	May 26, 2020

Abstract

An acoustic device includes first and second acoustic cavities which are air tight. A first passive radiator includes a first passive radiator diaphragm that has a rear surface which is exposed to the first acoustic cavity. A second passive radiator includes a first passive radiator diaphragm having a front surface which is exposed to the first acoustic cavity, and a rear surface which is exposed to the second acoustic cavity. A first electro-acoustic transducer is supported on the second passive radiator diaphragm. The first electro-acoustic transducer is arranged such that a first radiating surface of the first electro-acoustic transducer radiates acoustic energy into the first acoustic chamber and a second radiating surface of the first electro-acoustic transducer radiates acoustic energy into the second acoustic chamber.

First claim

What is claimed is:

1. An acoustic device, comprising:
a first acoustic cavity that is substantially air tight;
a second acoustic cavity that is substantially air tight;
a first passive radiator comprising a first passive radiator diaphragm having a rear surface which is exposed to the first acoustic cavity;
a second passive radiator comprising a second passive radiator diaphragm having a front surface which is exposed to the first acoustic cavity, and a rear surface which is exposed to the second acoustic cavity; and
a first electro-acoustic transducer supported on the second passive radiator diaphragm,
wherein the first electro-acoustic transducer is arranged such that a first radiating surface of the first electro-acoustic transducer radiates acoustic energy into the first acoustic chamber and a second radiating surface of the first electro-acoustic transducer radiates acoustic energy into the second acoustic chamber.

2. The acoustic device of claim 1 , further comprising an enclosure that defines the first and second acoustic cavities.

3. The acoustic device of claim 2 , further comprising a third passive radiator comprising a third passive radiator diaphragm having a rear surface which is exposed to the second acoustic cavity.

4. The acoustic device of claim 3 , wherein the first passive radiator has a first effective radiating area; the second passive radiator has a second effective radiating area, inclusive of an effective radiating area of the electro-acoustic transducer; and the third passive radiator has a third effective radiating area; and wherein the first, second, and third effective radiating areas are substantially the same.

5. The acoustic device of claim 4 , wherein the first passive radiator diaphragm is coupled to the enclosure by a first suspension element, the second passive radiator diaphragm is coupled to the enclosure by a second suspension element, and the third passive radiator diaphragm is coupled to the enclosure by a third suspension element.

6. The acoustic device of claim 4 , wherein the first passive radiator diaphragm, the second passive radiator diaphragm, and the third passive radiator diaphragm are each configured to vibrate, relative to the enclosure, along a common vibration axis.

7. The acoustic device of claim 6 , wherein the first electro-acoustic transducer includes a transducer diaphragm, a motor, and a surround that couples the transducer diaphragm to the second passive radiator diaphragm, and wherein the motor drives motion of the transducer diaphragm, relative to the second passive radiator diaphragm, along the common vibration axis.

8. The acoustic device of claim 2 , wherein the first passive radiator diaphragm and the second passive radiator diaphragm are each configured to vibrate, relative to the enclosure, along a common vibration axis.

9. The acoustic device of claim 8 , wherein the first electro-acoustic transducer includes a transducer diaphragm, a motor, and a surround that couples the transducer diaphragm to the second passive radiator diaphragm, and wherein the motor drives motion of the transducer diaphragm, relative to the second passive radiator diaphragm, along the common vibration axis.

10. The acoustic device of claim 1 , further comprising a first enclosure which defines the first acoustic cavity, and a second enclosure that defines the second acoustic cavity, wherein the first enclosure is mounted to the second passive radiator such that the first enclosure moves when the second passive radiator diaphragm vibrates.

11. The acoustic device of claim 10 , wherein the first passive radiator diaphragm is coupled to the first enclosure by a first suspension element such that the second passive radiator diaphragm can vibrate relative to the first enclosure, and the second passive radiator diaphragm is coupled to the second enclosure by a second suspension element such that the second passive radiator diaphragm can vibrate relative to the second enclosure.

12. The acoustic device of claim 11 , wherein the first passive radiator diaphragm, and the second passive radiator diaphragm both vibrate along a common vibration axis.

13. The acoustic device of claim 12 , wherein the first electro-acoustic transducer includes a transducer diaphragm, a motor, and a surround that couples the transducer diaphragm to the second passive radiator diaphragm, and wherein the motor drives motion of the transducer diaphragm, relative to the second passive radiator diaphragm, along the common vibration axis.

14. The acoustic device of claim 11 , further comprising a third enclosure that defines the third acoustic cavity, wherein the third enclosure is mounted to the fourth passive radiator such that the third enclosure moves when the fourth passive radiator diaphragm vibrates.

15. An acoustic device, comprising:
a first acoustic cavity;
a second acoustic cavity;
a first passive radiator comprising a first passive radiator diaphragm having a rear surface which is exposed to the first acoustic cavity;
a second passive radiator comprising a second passive radiator diaphragm having a front surface which is exposed to the first acoustic cavity, and a rear surface which is exposed to the second acoustic cavity; and
an electro-acoustic transducer supported on the second passive radiator diaphragm,
wherein the electro-acoustic transducer is arranged such that a first radiating surface of the electro-acoustic transducer radiates acoustic energy into the first acoustic chamber and a second radiating surface of the electro-acoustic transducer radiates acoustic energy into the second acoustic chamber.

16. The acoustic device of claim 15 , wherein the first passive radiator has a first effective radiating area and the second passive radiator has a second effective radiating area that is substantially equal to the first effective radiating area.

17. The acoustic device of claim 16 , further comprising:
a first suspension element acting on the first passive radiator, the first suspension element having a first effective stiffness, the first passive radiator having a first effective mass; and
a second suspension element acting on the second passive radiator, the second suspension element having a second effective stiffness, the second passive radiator having a second effective mass,
wherein the ratio of the first effective stiffness to the first effective mass is substantially equal to the ratio of the second effective stiffness to the second effective mass.

18. The acoustic device of claim 15 , further comprising:
a first suspension element acting on the first passive radiator, the first suspension element having a first effective stiffness, the first passive radiator having a first effective mass; and
a second suspension element acting on the second passive radiator, the second suspension element having a second effective stiffness, the second passive radiator having a second effective mass,
wherein the ratio of the first effective stiffness to the first effective mass is substantially equal to the ratio of the second effective stiffness to the second effective mass.

19. The acoustic device of claim 15 , further comprising a third passive radiator comprising a third passive radiator diaphragm having a rear surface which is exposed to the second acoustic cavity.

20. The acoustic device of claim 19 , wherein the first passive radiator has a first effective radiating area, the second passive radiator has a second effective radiating area, and the third passive radiator has a third effec

Assignees

• Bose Corp

Inventors

• Litovsky Roman N
• Williams Chester Smith
• Tiene Michael

Classifications

• H04R1/2834 Primary

  for loudspeaker transducers · CPC title

• H04R1/26

  Spatial arrangements of separate transducers responsive to two or more frequency ranges · CPC title