MULTIPLE MAGNET LOUDSPEAKER

• US 20090123005A1
• Filed: 11/14/2007
• Published: 05/14/2009
• Est. Priority Date: 11/14/2007
• Status: Active Grant

• Current Assignee: Harman International Industries Incorporated (Samsung Electronics Co. Ltd.)
• Original Assignee: Harman International Industries Incorporated (Samsung Electronics Co. Ltd.)
• Inventors: Hogue, Douglas K., Holt, Andrew, Canada, Michael A. SR.
• Granted Patent: US 8,135,162 B2
• Time in Patent Office: Days
• US Class Current: 381/117
• CPC Class Codes: H04R 1/24 Structural combinations of separate transducers or of two parts of the same transducer and responsive respectively to two or more frequency ranges
• CPC Class Codes: H04R 9/025 Magnetic circuit
• CPC Class Codes: H04R 9/063 using a plurality of acoustic drivers H04R1/24 and H04R1/403 take precedence

Abstract

A loudspeaker provides increased magnetic flux from multiple magnets to drive voice coils to generate sound. The loudspeaker is formed as a smaller profile and reduced weight package. The loudspeaker includes a dual pole, first and second magnets, first and second front plates, and first and second gaps. The polarities of the first and second magnets are aligned in the same direction. The first and second magnets may be disk or ring-shaped and may be coupled to a flange of the dual pole. The first and second gaps may be formed between the inner diameters of the first and second magnets and the dual pole. The magnetic flux produced by the first and second magnets may be combined, directed, and concentrated within the first and second gaps by the dual pole and the front plates. At least portions of a first and a second voice coil may be positioned within the first and second gaps, respectively, and diaphragms may be coupled to the first and second voice coils.

Claims

1. A loudspeaker having a magnet structure, the magnet structure comprising:

a dual pole comprising a core, a first planar surface, and a second planar surface;

a first magnet coupled to the first planar surface; and

a second magnet coupled to the second planar surface;

where the first and second magnets are positioned so that a polarity of the first magnet is aligned in a same direction as a polarity of the second magnet.

2. The magnet structure of claim 1, where the second planar surface is substantially opposite the first planar surface, and the first and second planar surfaces form a flange that extends substantially perpendicularly away from the core.

3. The magnet structure of claim 1, where the first and second magnets have a substantially annular shape, and the dual pole, the first magnet, and the second magnet are substantially concentric about a central axis of the magnet structure.

4. The magnet structure of claim 1, further comprising:

a first front plate coupled to the first magnet;

a first gap formed between the first front plate and the dual pole;

a second front plate coupled to the second magnet; and

a second gap formed between the second front plate and the dual pole;

where the first and second front plates are positioned to combine, direct, and concentrate a magnetic flux of the first and second magnets substantially within the first and second gaps.

5. The magnet structure of claim 4, where the first and second front plates have a substantially annular shape and are substantially concentric about a central axis of the magnet structure.

6. The magnet structure of claim 1, further comprising:

a first front plate coupled to the first magnet and comprising a stepped shape with a thicker inner portion relative to an outer portion; and

a second front plate coupled to the second magnet and comprising a partial wedge shape;

where the first and second magnets extend laterally beyond the first and second planar surfaces of the dual pole.

7. The magnet structure of claim 1, where the core comprises an orifice formed in an inner surface of the core, the orifice adapted to allow support of the magnet structure in the loudspeaker.

8. A loudspeaker having a magnet structure, the magnet structure comprising:

a first magnet having a first polarity and a first magnetic flux;

a second magnet having a second polarity aligned in a same direction as the first polarity, and a second magnetic flux; and

a dual pole coupled to the first and second magnets, the dual pole comprising a core,

where a combined magnetic flux flows substantially in the dual pole, the combined magnetic flux comprising the first magnetic flux and the second magnetic flux.

9. The magnet structure of claim 8, where the dual pole further comprises a flange, the first and second magnets coupled to the flange and positioned such that the combined magnetic flux flows substantially in the core and the flange, the flange extending substantially perpendicularly away from the core.

10. The magnet structure of claim 8, where the first and second magnets have a substantially annular shape, and the dual pole, the first magnet, and the second magnet are substantially concentric about a central axis of the magnet structure.

11. The magnet structure of claim 8, further comprising:

a first front plate coupled to the first magnet;

a first gap formed between the first front plate and the dual pole;

a second front plate coupled to the second magnet; and

a second gap formed between the second front plate and the dual pole;

where the first and second front plates are positioned to direct and concentrate the combined magnetic flux substantially within the first and second gaps.

12. The magnet structure of claim 11, where the first and second front plates have a substantially annular shape and are substantially concentric about a central axis of the magnet structure.

13. The magnet structure of claim 8, further comprising:

a first front plate coupled to the first magnet and comprising a stepped shape with a thicker inner portion relative to an outer portion; and

a second front plate coupled to the second magnet and comprising a partial wedge shape;

where the first and second magnets extend laterally beyond the first and second planar surfaces of the dual pole.

14. The magnet structure of claim 8, where the core comprises an orifice formed in an inner surface of the core, the orifice adapted to allow support of the magnet structure in the loudspeaker.

15. A method of manufacturing a magnet structure of a loudspeaker, comprising:

providing a dual pole, the dual pole comprising a core, a first planar surface, and second planar surface;

coupling a first magnetic material to the first planar surface and a second magnetic material to the second planar surface; and

magnetizing the first and second magnetic materials such that a polarity of the first magnetic material is aligned in a same direction as a polarity of the second magnetic material, if the first and second magnetic materials are not already magnetized.

16. The method of claim 15, further comprising forming a flange that extends perpendicularly away from the core, the flange formed from the first and second planar surfaces.

17. The method of claim 15, further comprising positioning the dual pole, the first magnetic material, and the second magnetic material to be substantially concentric about a central axis of the magnet structure, the first and second magnetic materials having a substantially annular shape.

18. The method of claim 15, further comprising:

coupling a first front plate to the first magnetic material;

forming a first gap between the first front plate and the dual pole;

coupling a second front plate to the second magnetic material; and

forming a second gap between the second front plate and the dual pole;

such that the first and second front plates are positioned to combine, direct, and concentrate a magnetic flux of the first and second magnetic materials substantially within the first and second gaps.

19. The method of claim 18, further comprising positioning the first and second front plates to be substantially concentric about a central axis of the magnet structure, the first and second front plates have a substantially annular shape.

20. The method of claim 15, further comprising forming an orifice in an inner surface of the core, the orifice adapted to allow support of the magnet structure in the loudspeaker.