Malcolm Eldridge Williams

US Patent:

7607437, Oct 27, 2009

Filed:

May 18, 2004

Appl. No.:

10/847693

Inventors:

David Boyle - Monrovia CA, US
Michael Holmes - Redlands CA, US
Malcolm Williams - San Clemente CA, US

Assignee:

Cardinal Health 203, Inc. - Wilmington DE

International Classification:

A61M 16/00
H02P 5/00

US Classification:

12820421, 12820418, 388800

Abstract:

A method and apparatus for controlling a brushless DC (BLDC) motor over a wide range of angular speeds is presented. Analog magnetic sensors provide continuous signal measurements related to the rotor angular position at a sample rate independent of rotor angular speed. In one embodiment, analog signal measurements are subsequently processed using an arctangent function to obtain the rotor angular position. The arctangent may be computed using arithmetic computation, a small angle approximation, a polynomial evaluation approach, a table lookup approach, or a combination of various methods. In one embodiment, the BLDC rotor is used to drive a Roots blower used as a compressor in a portable mechanical ventilator system.

US Patent:

20080092892, Apr 24, 2008

Filed:

Oct 23, 2007

Appl. No.:

11/877117

Inventors:

David Boyle - Monrovia CA, US
Michael Holmes - Redlands CA, US
Malcolm Williams - San Clemente CA, US

Assignee:

Pulmonetic Systems, Inc. - Minneapolis MN

International Classification:

G05D 7/06
A61M 16/00
H02P 7/285
A62B 7/00

US Classification:

128204210, 388809000, 700282000

Abstract:

A method and apparatus for controlling a brushless DC (BLDC) motor over a wide range of angular speeds is presented. Analog magnetic sensors provide continuous signal measurements related to the rotor angular position at a sample rate independent of rotor angular speed. In one embodiment, analog signal measurements are subsequently processed using an arctangent function to obtain the rotor angular position. The arctangent may be computed using arithmetic computation, a small angle approximation, a polynomial evaluation approach, a table lookup approach, or a combination of various methods. In one embodiment, the BLDC rotor is used to drive a Roots blower used as a compressor in a portable mechanical ventilator system.

US Patent:

20080092893, Apr 24, 2008

Filed:

Oct 23, 2007

Appl. No.:

11/877168

Inventors:

David Boyle - Monrovia CA, US
Michael Holmes - Redlands CA, US
Malcolm Williams - San Clemente CA, US

Assignee:

Pulmonetic Systems, Inc. - Minneapolis MN

International Classification:

G05D 7/06
A61M 16/00
H02P 7/285
A62B 7/00

US Classification:

128204210, 388809000, 700282000

Abstract:

A method and apparatus for controlling a brushless DC (BLDC) motor over a wide range of angular speeds is presented. Analog magnetic sensors provide continuous signal measurements related to the rotor angular position at a sample rate independent of rotor angular speed. In one embodiment, analog signal measurements are subsequently processed using an arctangent function to obtain the rotor angular position. The arctangent may be computed using arithmetic computation, a small angle approximation, a polynomial evaluation approach, a table lookup approach, or a combination of various methods. In one embodiment, the BLDC rotor is used to drive a Roots blower used as a compressor in a portable mechanical ventilator system.