Patents by Inventor Steven D. Pratt
Steven D. Pratt 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).
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Publication number: 20080145736Abstract: A device for transferring fluid in a fuel cell power system. The device has a first barrier layer and a second barrier layer. Sealing portions bond the first and second barrier layers together in predetermined areas, to define one or more unbonded pathways between the barrier layers. The pathways are adapted to transport fluid through the device. Ports through a layer provide pathway fluid ingress and egress.Type: ApplicationFiled: December 15, 2006Publication date: June 19, 2008Inventors: Steven D. Pratt, Ronald J. Kelley
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Patent number: 7184756Abstract: Devices (302, 702, 800) with embedded control programs are provided are provided with RF-ID devices (114, 504) or other non-contact read data carriers (604) that provide configuration data, on which the execution of the embedded control programs is contingent. Preferred embodiments include wireless communication devices (302, 702, 800) provided with RF-ID devices (114, 504) or set of magnets (604) that encodes data embedded in front fascia. Embodiments of the invention increase the security of configuration data, and allow for functionality to enhanced by replacing the front fascia.Type: GrantFiled: June 12, 2003Date of Patent: February 27, 2007Assignee: Motorola Inc.Inventors: Ronald J. Kelley, Steven D. Pratt, Sivakumar Muthuswamy
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Patent number: 7132192Abstract: A fuel cell (100) includes a membrane electrode assembly (110) located together with a layer of variable porosity porous gas diffusion material (150). The variable porosity gas diffusion material layer (150) operates to selectively limit the amount of reactants reaching localized areas of the membrane electrode assembly (110) in order to reduce hot spots.Type: GrantFiled: October 17, 2003Date of Patent: November 7, 2006Assignee: Motorola, Inc.Inventors: Sivakumar Muthuswamy, Steven D. Pratt, Ronald J. Kelley, Gene Kim
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Patent number: 7108931Abstract: A fuel cell (200) includes a membrane electrode assembly (210) located together with a layer of porous, z-axis electrically conductive, non-linear positive temperature coefficient (NPTC) material (250). The NPTC material (250) operates to selectively limit the amount of electrons collected from localized areas of the membrane electrode assembly (210) in order to reduce hot spots.Type: GrantFiled: March 24, 2004Date of Patent: September 19, 2006Assignee: Motorola, Inc.Inventors: Sivakumar Muthuswamy, Steven D. Pratt, Ronald J. Kelley
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Patent number: 6986957Abstract: A direct methanol fuel cell system 100 uses dissolved catalyst to promote a fuel cell reaction that takes place in an anode sub-chamber 110 of a fuel cell 102. According to the preferred embodiment the dissolved catalyst comprises a macro cyclic coordinated compound of platinum. The dissolved catalyst is preferably continuously circulated through the anode sub-chamber 110, and is preferably mixed in a mixing valve 118 with methanol and water in order to promote its catalytic action.Type: GrantFiled: December 9, 2002Date of Patent: January 17, 2006Assignee: Motorola, Inc.Inventors: Bobby Dean Landreth, Steven D. Pratt, Sivakumar Muthuswamy, Ronald J. Kelley, Robert W. Pennisi
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Patent number: 6926990Abstract: A fuel cell device has a composite particle electrode (200) formed using particles (210) having a combination of ion conductor material, electron conductor material, and catalyst material. Each composite particle (210) is preferably formed to have a substantially spherical outer layer (480) of ion conductor material (481) with conductive and catalyst particles (482, 484) are dispersed throughout the outer layer (480). An array of composite particles (210) is layered in a substantially structured or ordered manner on a membrane support structure (220) to form the fuel cell electrode. A fuel cell electrode so formed has interstitial gaps between the composite particles that result in a structure permeable to oxygen and other fluids.Type: GrantFiled: August 29, 2002Date of Patent: August 9, 2005Assignee: Motorola, Inc.Inventors: Ronald J. Kelley, Steven D. Pratt, Sivakumar Muthuswamy, Robert W. Pennisi
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Patent number: 6888607Abstract: Rewritable signs (100, 1300) that include bistable cholesteric liquid crystal layers (102, 1402, 1404, 1406) are provided. According to one embodiment a rewritable sign (100) is devoid of circuitry for establishing electric fields in localize regions for writing information to the rewritable sign (100), and is consequently inexpensive. In the latter embodiment, a separate information writer (400) that includes an array of pixel electrodes (404) that is driven by an active matrix (602) is used to write information on the rewritable sign. According to another embodiment a rewritable sign (1300) includes three cholesteric liquid layers (1402, 1404, 1406) each of which reflects a different primary color. The three cholesteric liquid crystal layers (1402, 1404, 1406) are interleaved with sets of conductive lines (1316, 1320, 1322, 1324) that are used to apply signals to the cholesteric liquid crystal layers (1402, 1404, 1406) for the purpose of writing information.Type: GrantFiled: August 29, 2002Date of Patent: May 3, 2005Assignee: Motorola, Inc.Inventors: Bobby Dean Landreth, Steven D. Pratt, Robert W. Pennisi, Ronald J. Kelley, Sivakumar Muthuswamy, David S. Fredley
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Patent number: 6869708Abstract: A small fuel cell (10) powers a portable electronic device (12) and contains a fuel reservoir (14) and a device (16) that measures the amount of liquid fuel (18) that is in the reservoir. The fuel cell operates on hydrogen that is obtained from a liquid hydrocarbon fuel, such as alcohol or other hydrocarbons. The liquid fuel is typically converted into hydrogen by a reforming process. The reservoir that is connected to the fuel cell has an indicia (19) that is readable by a human user of the portable electronic device, for measuring the amount of liquid hydrocarbon fuel that is present in the reservoir. Typically, the indicia consist of a sight glass, a capacitive element, a resistive element, a transparent portion of the reservoir, a float, or an acoustic transmitter coupled with an acoustic receiver.Type: GrantFiled: July 16, 2003Date of Patent: March 22, 2005Assignee: Motorola, Inc.Inventors: Ronald J. Kelley, Sivakumar Muthuswamy, Steven D. Pratt, Robert W. Pennisi
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Publication number: 20040253944Abstract: Devices (302, 702, 800) with embedded control programs are provided are provided with RF-ID devices (114, 504) or other non-contact read data carriers (604) that provide configuration data, on which the execution of the embedded control programs is contingent. Preferred embodiments include wireless communication devices (302, 702, 800) provided with RF-ID devices (114, 504) or set of magnets (604) that encodes data embedded in front fascia. Embodiments of the invention increase the security of configuration data, and allow for functionality to enhanced by replacing the front fascia.Type: ApplicationFiled: June 12, 2003Publication date: December 16, 2004Inventors: Ronald J. Kelley, Steven D. Pratt, Sivakumar Muthuswamy
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Publication number: 20040203525Abstract: A portable electronic device (100) includes a keypad (e.g. 300) that may be actuated from either side of a single substrate (301, 401, 501, 601, 701, 801). The keypad includes inner actuators (103) and outer actuators (205) that provide active contact, support and tactile feel from both sides of the substrate. The electronic device gains greater operability and utility since a single keypad is operable from either side of one housing.Type: ApplicationFiled: December 31, 2002Publication date: October 14, 2004Applicant: Motorola, Inc.Inventors: Joseph G. Gillette, Scott Potter, Sivakumar Muthuswamy, Steven D. Pratt
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Publication number: 20040185311Abstract: A fuel cell (200) includes a membrane electrode assembly (210) located together with a layer of porous, z-axis electrically conductive, non-linear positive temperature coefficient (NPTC) material (250). The NPTC material (250) operates to selectively limit the amount of electrons collected from localized areas of the membrane electrode assembly (210) in order to reduce hot spots.Type: ApplicationFiled: March 24, 2004Publication date: September 23, 2004Inventors: Sivakumar Muthuswamy, Steven D. Pratt, Ronald J. Kelley
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Publication number: 20040131921Abstract: A direct methanol fuel cell system 100 uses dissolved catalyst to promote a fuel cell reaction that takes place in an anode sub-chamber 110 of a fuel cell 102. According to the preferred embodiment the dissolved catalyst comprises a macro cyclic coordinated compound of platinum. The dissolved catalyst is preferably continuously circulated through the anode sub-chamber 110, and is preferably mixed in a mixing valve 118 with methanol and water in order to promote its catalytic action.Type: ApplicationFiled: December 9, 2002Publication date: July 8, 2004Inventors: Bobby Dean Landreth, Steven D. Pratt, Sivakumar Muthuswamy, Ronald J. Kelley, Robert W. Pennisi
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Patent number: 6756142Abstract: A fuel cell (200) includes a membrane electrode assembly (210) located together with a layer of porous, z-axis electrically conductive, non-linear positive temperature coefficient (NPTC) material (250). The NPTC material (250) operates to selectively limit the amount of electrons collected from localized areas of the membrane electrode assembly (210) in order to reduce hot spots.Type: GrantFiled: October 31, 2001Date of Patent: June 29, 2004Assignee: Motorola, Inc.Inventors: Sivakumar Muthuswamy, Steven D. Pratt, Ronald J. Kelley
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Patent number: 6743543Abstract: A fuel cell (100) includes a membrane electrode assembly (110) located together with a layer of variable porosity porous gas diffusion material (150). The variable porosity gas diffusion material layer (150) operates to selectively limit the amount of reactants reaching localized areas of the membrane electrode assembly (110) in order to reduce hot spots.Type: GrantFiled: October 31, 2001Date of Patent: June 1, 2004Assignee: Motorola, Inc.Inventors: Sivakumar Muthuswamy, Steven D. Pratt, Ronald J. Kelley
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Publication number: 20040086776Abstract: A fuel cell (100) includes a membrane electrode assembly (110) located together with a layer of variable porosity porous gas diffusion material (150). The variable porosity gas diffusion material layer (150) operates to selectively limit the amount of reactants reaching localized areas of the membrane electrode assembly (110) in order to reduce hot spots.Type: ApplicationFiled: October 17, 2003Publication date: May 6, 2004Applicant: Motorola, Inc.Inventors: Sivakumar Muthuswamy, Steven D. Pratt, Ronald J. Kelley
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Publication number: 20040041971Abstract: Rewritable signs (100, 1300) that include bistable cholesteric liquid crystal layers (102, 1402, 1404, 1406) are provided. According to one embodiment a rewritable sign (100) is devoid of circuitry for establishing electric fields in localize regions for writing information to the rewritable sign (100), and is consequently inexpensive. In the latter embodiment, a separate information writer (400) that includes an array of pixel electrodes (404) that is driven by an active matrix (602) is used to write information on the rewritable sign. According to another embodiment a rewritable sign (1300) includes three cholesteric liquid layers (1402, 1404, 1406) each of which reflects a different primary color. The three cholesteric liquid crystal layers (1402, 1404, 1406) are interleaved with sets of conductive lines (1316, 1320, 1322, 1324) that are used to apply signals to the cholesteric liquid crystal layers (1402, 1404, 1406) for the purpose of writing information.Type: ApplicationFiled: August 29, 2002Publication date: March 4, 2004Inventors: Bobby Dean Landreth, Steven D. Pratt, Robert W. Pennisi, Ronald J. Kelley, Sivakumar Muthuswamy, David S. Fredley
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Publication number: 20040043282Abstract: A fuel cell device has a composite particle electrode (200) formed using particles (210) having a combination of ion conductor material, electron conductor material, and catalyst material. Each composite particle (210) is preferably formed to have a substantially spherical outer layer (480) of ion conductor material (481) with conductive and catalyst particles (482, 484) are dispersed throughout the outer layer (480). An array of composite particles (210) is layered in a substantially structured or ordered manner on a membrane support structure (220) to form the fuel cell electrode. A fuel cell electrode so formed has interstitial gaps between the composite particles that result in a structure permeable to oxygen and other fluids.Type: ApplicationFiled: August 29, 2002Publication date: March 4, 2004Inventors: Ronald J. Kelley, Steven D. Pratt, Sivakumar Muthuswamy, Robert W. Pennisi
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Patent number: 6699611Abstract: A thermo-responsive polymer is incorporated into a fuel cell (50) in order to maintain optimum hydration of the polymer electrolyte membrane. The thermo-responsive polymer (52) is situated proximate to the membrane electrode assembly (54) such that fuel or oxidant gas passes (56) through the thermo-responsive polymer to the membrane electrode assembly. The thermo-responsive polymer swells or shrinks in response to changes in the operating temperature of the membrane electrode assembly, altering the flow rate of the fuel or oxidant gas passing through the thermo-responsive polymer.Type: GrantFiled: May 29, 2001Date of Patent: March 2, 2004Assignee: Motorola, Inc.Inventors: Gene Kim, Ronald J. Kelley, Steven D. Pratt
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Patent number: D537742Type: GrantFiled: October 24, 2005Date of Patent: March 6, 2007Assignee: Motorola, Inc.Inventors: Yesenia V. Escorcia, Steven D. Pratt
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Patent number: D578116Type: GrantFiled: August 15, 2006Date of Patent: October 7, 2008Assignee: Motorola, Inc.Inventors: Kevin S. Olcott, Philip J. Hill, Jorge I. Rodriquez, Shawn P. Welsh, Yesenia V. Escorcia, Steven D. Pratt