Nathan Mitchell

US Patent:

6595269, Jul 22, 2003

Filed:

May 17, 2001

Appl. No.:

09/859877

Inventors:

Nathan A. Mitchell - The Woodlands TX

Assignee:

Hewlett-Packard Development Company, L.P. - Houston TX

International Classification:

F28F 500

US Classification:

165 86, 16510433, 16510426, 361687

Abstract:

A notebook computer has a base housing with a heat-generating microprocessor therein, and a lid housing pivotally connected to the base housing. Operating heat from the microprocessor is transferred to the lid housing, for dissipation therefrom, via a specially designed thermosyphoning heat pipe structure formed from first and second heat pipes. The first heat pipe representatively has a rectangular cross-section, an evaporating portion thermally communicated with the microprocessor, and a coiled condensing portion centered about the lid hinge line and having a circularly cross-sectioned interior side surface portion defined by flat sides of the first heat pipe. The second heat pipe has a circular cross-section, an evaporating portion pivotally received within the coiled first heat pipe portion, and a condensing portion thermally communicated with the lid housing. When the lid housing is opened and closed, the evaporating portion of the second heat pipe is rotated within the coiled first heat pipe portion and slidably engages its circularly cross-sectioned interior side portion.

US Patent:

6912785, Jul 5, 2005

Filed:

May 17, 2001

Appl. No.:

09/859723

Inventors:

Nathan A. Mitchell - The Woodlands TX, US

Assignee:

Hewlett-Packard Development Company, L.P. - Houston TX

International Classification:

B23P015/00
B23P015/26

US Classification:

29890032, 29890036, 29890037

Abstract:

A notebook computer has a base housing with a heat-generating microprocessor therein, and a lid housing pivotally connected to the base housing. Operating heat from the microprocessor is transferred to the lid housing, for dissipation therefrom, via a specially designed thermosyphoning heat pipe structure formed from first and second heat pipes. The first heat pipe representatively has a rectangular cross-section, an evaporating portion thermally communicated with the microprocessor, and a coiled condensing portion centered about the lid hinge line and having a circularly cross-sectioned interior side surface portion defined by flat sides of the first heat pipe. The second heat pipe has a circular cross-section, an evaporating portion pivotally received within the coiled first heat pipe portion, and a condensing portion thermally communicated with the lid housing. When the lid housing is opened and closed, the evaporating portion of the second heat pipe is rotated within the coiled first heat pipe portion and slidably engages its circularly cross-sectioned interior side portion.

US Patent:

6950729, Sep 27, 2005

Filed:

May 21, 2001

Appl. No.:

09/862781

Inventors:

Nathan Mitchell - The Woodlands TX, US
Joseph F. Freiman - Cypress TX, US

International Classification:

G05D011/00

US Classification:

700286, 700195, 423439, 428402, 428570, 428627, 428634, 429 42, 429 44

Abstract:

A portable electronic system which obtains power from a dry-electrolyte fuel cell. Water which is produced by the fuel cell is atomized by an ultrasonic transducer, to avoid user inconvenience due to reservoirs or dripping.

US Patent:

58618120, Jan 19, 1999

Filed:

Dec 18, 1996

Appl. No.:

8/768477

Inventors:

Nathan Austin Mitchell - The Woodlands TX
Joseph F. Freiman - Cypress TX
Steven Kent McConkey - Houston TX

Assignee:

Compaq Computer Corporation - Houston TX

International Classification:

G08B 2100
H02J 704

US Classification:

340636

Abstract:

A removable battery pack for powering a pen-based or portable computer system in which the battery pack blocks its terminals when inserted into an unknown system. The known system includes a power supply microcontroller which passes battery charge data back and forth between a memory located in the battery pack and the power supply microcontroller. A battery microcontroller, located in the battery pack, eavesdrops drops on the communication between the power supply microcontroller and the memory, and when it validates a known signature of this communication, the battery microcontroller then enables the terminals of the battery pack. A trickle discharge current flows from the battery pack whenever the battery pack is out of the known system to allow the power supply microcontroller to power up in the case of a dead auxiliary battery.

US Patent:

62538365, Jul 3, 2001

Filed:

May 24, 1999

Appl. No.:

9/317332

Inventors:

Nathan A. Mitchell - The Woodlands TX

Assignee:

Compaq Computer Corporation - Houston TX

International Classification:

F28D 1100

US Classification:

165 86

Abstract:

A notebook computer has a base housing with a heat-generating microprocessor therein, and a lid housing pivotally connected to the base housing. Operating heat from the microprocessor is transferred to the lid housing, for dissipation therefrom, via a specially designed thermosyphoning heat pipe structure formed from first and second heat pipes. The first heat pipe representatively has a rectangular cross-section, an evaporating portion thermally communicated with the microprocessor, and a coiled condensing portion centered about the lid hinge line and having a circularly cross-sectioned interior side surface portion defined by flat sides of the first heat pipe. The second heat pipe has a circular cross-section, an evaporating portion pivotally received within the coiled first heat pipe portion, and a condensing portion thermally communicated with the lid housing. When the lid housing is opened and closed, the evaporating portion of the second heat pipe is rotated within the coiled first heat pipe portion and slidably engages its circularly cross-sectioned interior side portion.

US Patent:

60182296, Jan 25, 2000

Filed:

Jun 30, 1997

Appl. No.:

8/884928

Inventors:

Nathan Mitchell - The Woodlands TX
Joseph F. Freiman - Cypress TX
Thomas Sawyers - Houston TX

Assignee:

Compaq Computer Corporation - Houston TX

International Classification:

H02J 700

US Classification:

320112

Abstract:

A sealed rechargeable lithium-ion battery pack which includes a switching voltage regulator. The regulator uses the normal cutoff transistors as the switching devices, and also includes a discrete inductor in the battery pack. The regulator is operated with programmable voltage and current parameters, under control of a microcontroller which is also inside the sealed battery pack enclosure.

US Patent:

56415877, Jun 24, 1997

Filed:

Dec 15, 1995

Appl. No.:

8/573296

Inventors:

Nathan Austin Mitchell - The Woodlands TX
Joseph F. Freiman - Cypress TX
Steven Kent McConkey - Houston TX

Assignee:

Compaq Computer Corporation - Houston TX

International Classification:

H01M 1048
H02J 704

US Classification:

429 90

Abstract:

A removable battery pack for powering a pen-based or portable computer system in which the battery pack blocks its terminals when inserted into an unknown system. The known system includes a power supply microcontroller which passes battery charge data back and forth between a memory located in the battery pack and the power supply microcontroller. A battery microcontroller, located in the battery pack, eavesdrops drops on the communication between the power supply microcontroller and the memory, and when it validates a known signature of this communication, the battery microcontroller then enables the terminals of the battery pack. A trickle discharge current flows from the battery pack whenever the battery pack is out of the known system to allow the power supply microcontroller to power up in the case of a dead auxiliary battery.

US Patent:

61372684, Oct 24, 2000

Filed:

Jun 30, 1997

Appl. No.:

8/885215

Inventors:

Nathan Mitchell - The Woodlands TX
Joseph F. Freiman - Cypress TX

Assignee:

Compaq Computer Corporation - Houston TX

International Classification:

H02J 704

US Classification:

320149

Abstract:

A battery charging system in which current is averaged over a long time period (seconds) to determine the maximum average charging rate. When the integral of charging current over this long period reaches the programmed maximum charge value for one period, current is simply cut off for the remainder of the fixed long period.