Patents by Inventor Nathan Mitchell

Nathan Mitchell has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 6595269
    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.
    Type: Grant
    Filed: May 17, 2001
    Date of Patent: July 22, 2003
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventor: Nathan A. Mitchell
  • Patent number: 6587612
    Abstract: A thermally actuated spectroscopic optical switch including reflective surfaces which are selectively moved into a position intersecting a beam of light by applying electrical or heat energy to a selected composite cantilever beam on which the reflective surface is mounted.
    Type: Grant
    Filed: September 6, 2000
    Date of Patent: July 1, 2003
    Assignee: Southwest Research Institute
    Inventors: Joseph Nathan Mitchell, Martin Peter W├╝est
  • Publication number: 20030002133
    Abstract: A thermal actuator includes a first arm having a proximal end and a distal end, a second arm, parallel to the first arm, having a proximal end and a distal end, and a third arm arranged between and parallel to the first and second arms, the third arm having a proximal end and a distal end. The third arm has at least one portion at the distal end of the third arm having a width that is substantially larger than a width of the first arm and a width of the second arm. The distal ends of the first, second and third arms are coupled together to form a distal end of the thermal actuator, and the first, second and third arms preferably are made of a single material.
    Type: Application
    Filed: June 28, 2001
    Publication date: January 2, 2003
    Applicant: SOUTH WEST RESEARCH INSTITUTE
    Inventors: Heather Shannon Hanson, Joseph Nathan Mitchell
  • Publication number: 20020008960
    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.
    Type: Application
    Filed: May 17, 2001
    Publication date: January 24, 2002
    Inventor: Nathan A. Mitchell
  • Publication number: 20010022720
    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.
    Type: Application
    Filed: May 17, 2001
    Publication date: September 20, 2001
    Inventor: Nathan A. Mitchell
  • Publication number: 20010023378
    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.
    Type: Application
    Filed: May 21, 2001
    Publication date: September 20, 2001
    Inventors: Nathan Mitchell, Joseph F. Freiman
  • Patent number: 6259971
    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.
    Type: Grant
    Filed: June 30, 1997
    Date of Patent: July 10, 2001
    Assignee: Compaq Computer Corporation
    Inventors: Nathan Mitchell, Joseph F. Freiman
  • Patent number: 6253836
    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.
    Type: Grant
    Filed: May 24, 1999
    Date of Patent: July 3, 2001
    Assignee: Compaq Computer Corporation
    Inventor: Nathan A. Mitchell
  • Patent number: 6137268
    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.
    Type: Grant
    Filed: June 30, 1997
    Date of Patent: October 24, 2000
    Assignee: Compaq Computer Corporation
    Inventors: Nathan Mitchell, Joseph F. Freiman
  • Patent number: 6040684
    Abstract: A lithium-ion cell charging system wherein pulse charging (with excursions above the critical voltage) is followed (once average current has fallen low enough) by charging in a linear regulator mode, using a transistor internal to a battery pack as an element of a linear regulator.
    Type: Grant
    Filed: June 30, 1997
    Date of Patent: March 21, 2000
    Assignee: Compaq Computer Corporation
    Inventor: Nathan Mitchell
  • Patent number: 6018229
    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.
    Type: Grant
    Filed: June 30, 1997
    Date of Patent: January 25, 2000
    Assignee: Compaq Computer Corporation
    Inventors: Nathan Mitchell, Joseph F. Freiman, Thomas Sawyers
  • Patent number: 5911947
    Abstract: A method for fan-folding lithium-ion-polymer battery cells, wherein gaps are left in the active material at fold locations of the metallic backing conductor. This avoids fatigue at the fold locations when the active materials expand and contract during charge and discharge.
    Type: Grant
    Filed: June 30, 1997
    Date of Patent: June 15, 1999
    Assignee: Compaq Computer Corporation
    Inventor: Nathan Mitchell
  • Patent number: 5630132
    Abstract: A data processing system for executing multimedia applications which interface with multimedia devices that consume or produce at least one of real-time and asynchronous streamed data includes a CPU for execution of one or more multimedia applications and a DSP for processing data including streamed data. A plurality of modular multimedia software tasks may be called by the multimedia application for execution in the DSP. A plurality of data communication modules are provided for linking selected ones of the software tasks with selected others of the software tasks, and linking selected multimedia devices with selected ones of the software tasks. Each of the communications modules allows continuous, real-time and unidirectional communication of streamed data.
    Type: Grant
    Filed: May 23, 1995
    Date of Patent: May 13, 1997
    Assignee: International Business Machines Corporation
    Inventors: Gary G. Allran, Donald E. Carmon, Fetchi Chen, Jose A. Eduartez, Charles R. Knox, William L. Lawton, Llewellyn B. Marshall, Nathan A. Mitchell, Malcolm C. Ware, Raymond W. Weeks, Charles R. Young
  • Patent number: 5625845
    Abstract: A data processing system is provided for executing multimedia applications which interface with multimedia end devices that consume or produce at least one of (a) real-time and (b) asynchronous streamed data. The data processing system includes a central processing unit for data processing operations including execution of the multimedia application, a digital signal processor for processing data including the streamed data, and a plurality of modular components which cooperate to provide a substantially open architecture.
    Type: Grant
    Filed: October 13, 1992
    Date of Patent: April 29, 1997
    Assignee: International Business Machines Corporation
    Inventors: Gary G. Allran, Donald E. Carmon, Fetchi Chen, Jose A. Eduartez, Charles R. Knox, William W. Lawton, Llewellyn B. Marshall, Nathan A. Mitchell, Malcolm S. Ware, Raymond W. Weeks, Yoav Medan, Uzi Shvadron
  • Patent number: 5309132
    Abstract: A technique for trimming photoresistors to change relatively high tolerance parts to relatively low tolerance parts by blocking out a portion of the photoactive area, and the so-trimmed photoresistors. The blocking out can be performed by placing ink over the photo-active area. This ink placement step can be easily added in the photoresistor assembly line after the initial calibration location.
    Type: Grant
    Filed: April 2, 1993
    Date of Patent: May 3, 1994
    Assignee: Compaq Computer Corporation
    Inventors: Nathan A. Mitchell, Philip J. McKenzie
  • Patent number: 5272327
    Abstract: A LCD backlight system which regulates the light generated by the lamp by controlling the intensity of the light using a photoresistor cell. The current provided to the lamp is controlled by a pulse width modulation (PWM) signal. The PWM signal responds to brightness adjustments by the user and to a photoresistor exposed to the light from the lamp. An operational amplifier circuit controls the PWM signal so that if the lamp is too bright, the current to the lamp is reduced, and if the lamp is too dim, the current to the lamp is increased. When the lamp brightness reaches the appropriate intensity, the output of the operational amplifier is unchanging, causing the intensity of the lamp to remain stable.
    Type: Grant
    Filed: May 26, 1992
    Date of Patent: December 21, 1993
    Assignee: Compaq Computer Corporation
    Inventors: Nathan A. Mitchell, Phillip J. McKenzie