Douglas J Button

US Patent:

6768806, Jul 27, 2004

Filed:

Mar 18, 1999

Appl. No.:

09/271686

Inventors:

Douglas J. Button - Los Angeles CA
Ralph E. Hyde - Santa Clarita CA
Alex V. Salvatti - Northridge CA

Assignee:

Harman International Industries, Incorporated - Northridge CA

International Classification:

H04R 2500

US Classification:

381401, 381396, 381412, 381414

Abstract:

Loudspeakers and other transducers of the dual-voice-coil/dual-magnetic-gap type can be improved by the addition of one or more annular shorting rings strategically located in the vicinity of the two magnetic gaps. The shorting rings have no effect on a steady state magnetic field but act in opposition to any change in flux density or any displacement of the flux lines such as those that occur under the loading imposed when the voice coils are driven hard with audio frequency current. The location of the shorting rings determines their effect: location close to a voice coil reduces the voice coil inductance, location entirely within the magnetic flux loop centerline favors reduction of second harmonic and higher order even harmonic distortion, a centered location on the flux loop centerline, i. e. centered in the magnetic gap, favors reduction of third harmonic and higher odd order harmonic distortion, while location outside the flux loop as defined by its center line but near the voice coil acts generally to reduce harmonic distortion and reduce the voice coil inductance. Thus a plurality of rings can be strategically deployed at different locations so as to optimally suppress both even and odd order harmonic distortion and to reduce the voice coil inductance.

US Patent:

6774510, Aug 10, 2004

Filed:

Oct 25, 2000

Appl. No.:

09/696392

Inventors:

Jerry Moro - Moorpark CA
Douglas J. Button - Simi Valley CA

Assignee:

Harman International Industries, Inc. - Northridge CA

International Classification:

H04R 900

US Classification:

310 12, 381400, 381414, 381429

Abstract:

The present invention provides an electromagnetic drive motor assembly (EDMA) that has an inner flux return assembly formed from an upper pole piece and a lower pole piece oppositely disposed relative to each other along the center of the EDMA. An annularly positioned conductive ring (or flux stabilization ring) encircles the inner flux return assembly, concentrically in contact with the outside of the inner flux return assembly. Along the exterior side of the flux return pieces, is a magnet that is between a top plate and a bottom plate. Each plate contacts with the magnet to form a magnetically conductive system. A magnetic gap is formed in between the inner flux return assembly and the top and bottom plates. Disposed within the magnetic gap is a dual coil wound around a cylinder. The dual coil includes a first coil portion and a second coil portion.

US Patent:

6801634, Oct 5, 2004

Filed:

Jul 31, 2001

Appl. No.:

09/921191

Inventors:

Douglas J. Button - Simi Valley CA

Assignee:

Harman International Industries, Inc. - Northridge CA

International Classification:

H04R 2500

US Classification:

381398, 381403, 381407, 381430, 181171

Abstract:

The invention provides a continuous layer of polymer that is shaped to act as the suspension, the former, and an attachment to the diaphragm. The coil may be located within the pocket providing insulation to the coil thus preventing electrical short circuiting of the voice coil as the voice coil expands or contracts based on its operating temperature. The invention also provides an inner flange area of a suspension that may act as a spring generating additional acoustic energy from the compression driver. The inner flange area may also be tuned to vibrate at a predetermined high frequency. Thus, in certain applications, where more acoustic energy is desired at high frequency, the inner flange area may be tuned to provide that extra acoustic energy. To further increase the high frequency energy generated by the compression driver, the diaphragm may be coupled to the bottom side of the inner flange area. Such an arrangement places the diaphragm closer to the phasing plug to minimize the space or cavity between the two.

US Patent:

6847726, Jan 25, 2005

Filed:

Apr 9, 2003

Appl. No.:

10/410005

Inventors:

Douglas J. Button - Los Angeles CA, US
Ralph E. Hyde - Santa Clarita CA, US
Alex V. Salvatti - Northridge CA, US

Assignee:

Harman International Industries, Incorporated - Northridge CA

International Classification:

H04R 2500

US Classification:

381401, 381396, 381412, 381414

Abstract:

Loudspeaker and other transducers of the dual-voice-coil/dual-magnetic-gap type can be improved by the addition of one or more annular shorting rings strategically located in the vicinity of the two magnetic gaps. The shorting rings have no effect on a steady state magnetic field but act in opposition to any change in flux density or any displacement of the flux lines such as those that occur under the loading imposed when the voice coils are driven hard with audio frequency current. The location of the shorting rings determines their effect: location close to a voice coil reduces the voice coil inductance, location entirely within the magnetic flux loop centerline favors reduction of second harmonic distortion and higher order even harmonic distortion, a centered location on the flux loop centerline, i. e. centered in the magnetic gap, favors reduction of third harmonic and higher odd order harmonic distortion, while location outside the flux loop as defined by its center line but near the voice coil acts to generally reduce harmonic distortion and reduce the voice coil inductance. Thus a plurality of rings can be strategically deployed at different locations so as to optimally suppress both even and odd order harmonic distortion and to reduce the voice coil inductance.

US Patent:

7012345, Mar 14, 2006

Filed:

Jun 29, 2004

Appl. No.:

10/881993

Inventors:

Jerry Moro - Moorpark CA, US
Douglas J. Button - Simi Valley CA, US

Assignee:

Harman International Industries, Inc. - Northridge CA

International Classification:

H02K 41/00

US Classification:

310 12, 381414, 381412, 381420

Abstract:

The present invention provides an electromagnetic drive motor assembly (EDMA) that has an inner flux return assembly formed from an upper pole piece and a lower pole piece oppositely disposed relative to each other along the center of the EDMA. An annularly positioned conductive ring (or flux stabilization ring) encircles the inner flux return assembly, concentrically in contact with the outside of the inner flux return assembly. Along the exterior side of the flux return pieces, is a magnet that is between a top plate and a bottom plate. Each plate contacts with the magnet to form a magnetically conductive system. A magnetic gap is formed in between the inner flux return assembly and the top and bottom plates. Disposed within the magnetic gap is a dual coil wound around a cylinder. The dual coil includes a first coil portion and a second coil portion.

US Patent:

7095869, Aug 22, 2006

Filed:

Aug 31, 2004

Appl. No.:

10/931693

Inventors:

Douglas J. Button - Simi Valley CA, US

Assignee:

Harman International Industries, Inc. - Northridge CA

International Classification:

H04R 25/00

US Classification:

381423, 381343, 381398, 381407

Abstract:

The invention provides a continuous layer of polymer that is shaped to act as the suspension, the former, and an attachment to the diaphragm. The coil may be located within the pocket providing insulation to the coil thus preventing electrical short circuiting of the voice coil as the voice coil expands or contracts based on its operating temperature. The invention also provides an inner flange area of a suspension that may act as a spring generating additional acoustic energy from the compression driver. The inner flange area may also be tuned to vibrate at a predetermined high frequency. Thus, in certain applications, where more acoustic energy is desired at high frequency, the inner flange area may be tuned to provide that extra acoustic energy. To further increase the high frequency energy generated by the compression driver, the diaphragm may be coupled to the bottom side of the inner flange area. Such an arrangement places the diaphragm closer to the phasing plug to minimize the space or cavity between the two.

US Patent:

7447318, Nov 4, 2008

Filed:

Sep 7, 2001

Appl. No.:

09/949425

Inventors:

Douglas J. Button - Simi Valley CA, US
Paul Robert Williams - Stevenage, GB

Assignee:

Harman International Industries, Incorporated - Northridge CA

International Classification:

H03G 11/00
H04R 29/00
H04R 3/00
H04R 1/00

US Classification:

381 55, 381 56, 381 59, 381397, 381 96, 381116, 381 58

Abstract:

This invention provides a compensation system capable of compensating for power loss due to the power compression effects of the voice coil as the temperature of the voice coil increases. To compensate for the power compression effect, the invention predicts or estimates the temperature of the voice coil using a thermal-model, and adjusts the estimated temperature according to the cooling effect as the voice coil moves back and forth in the air gap. The thermal-model may be an equivalent electrical circuit that models the thermal circuit of a loudspeaker. With the input signal equating to the voltage delivered to the loudspeaker, the thermal-model estimates a temperature of the voice coil. The estimated temperature is then used to modify equalization parameters. To account for the cooling effect of the moving voice coil, the thermal resistance values may be modified dynamically, but since this cooling effect changes with frequency, a cooling equalization filter may be used to spectrally shape the cooling signal, whose RMS level may be used to modify the thermal resistance values. The invention may include a thermal limiter that determines whether the estimated voice coil temperature is below a predetermined maximum temperature to prevent overheating and possible destruction of the voice coil.

US Patent:

7684574, Mar 23, 2010

Filed:

Mar 8, 2006

Appl. No.:

11/371538

Inventors:

Douglas J. Button - Simi Valley CA, US

Assignee:

Harman International Industries, Incorporated - Northridge CA

International Classification:

H04R 25/00
H04R 9/06

US Classification:

381160, 381335, 381336, 381182

Abstract:

A reflective loudspeaker array is cooperatively operable with an acoustically reflective planar surface to provide a constructive combination of direct and reflected sound waves that produces a uniform sound field. The uniform sound field provides a controlled sound field in the vertical and horizontal direction, and also provides uniformity from distances close to the reflective loudspeaker array to far way. The direct and reflected sound waves are advantageously and constructively combinable to generate a focused beamwidth of soundwaves. The reflective loudspeaker array includes a plurality of loudspeakers coupled to a surface of the reflective loudspeaker array. The surface may be formed to include at least one curve with a radius of curvature. The reflective loudspeaker array may be placed adjacent an acoustically reflective planar surface such that a frontal plane of a loudspeaker adjacently located closest to the acoustically reflective planar surface is aligned perpendicularly, and a frontal plane of a loudspeaker spaced away from the acoustically reflective planar surface is not aligned perpendicularly.