David B Leach

US Patent:

6422807, Jul 23, 2002

Filed:

Nov 28, 2000

Appl. No.:

09/726213

Inventors:

David Leach - Niskayuna NY
Iain Robertson Kellock - Clifton Park NY
Larry Wayne Plemmons - late of Hamilton OH
Cedric Chow - Schenectady NY
Brendan Francis Sexton - Clifton Park NY
Mark Stewart Schroder - Hendersonville NC

Assignee:

General Electric Company - Schenectady NY

International Classification:

F01D 1124

US Classification:

415 1, 415136, 4151732, 415175, 415176, 415178

Abstract:

A method of operating a gas turbine having inner and outer shells, with the inner shell being radially movable relative to rotor bucket tip passage in the inner shell for flowing a thermal medium. A pair of passage portions are formed in each of the aft and forward inner shell sections with axially communicating passageways between the passage portions. A thermal medium, preferably from an off-turbine site, is provided for flow through the second-stage aft inner shell section, along axial passageways along the mid-line of the inner shell to a first passage portion of the forward inner shell section. Cross-over paths flow the thermal medium from the first passage portions to second circumferentially extending passage portions of the forward inner shell section, in turn, in communication with axial passageways extending from the forward section to the aft section. A second pair of passage portions flow the thermal medium to an outlet in the aft section. By controlling the temperature of the thermal medium for flow through the aft and forward sections of the inner shell, the clearance between the shrouds and the tips of the buckets for at least the first and second stages of the turbine is controllably adjusted.

US Patent:

6457936, Oct 1, 2002

Filed:

Sep 20, 2000

Appl. No.:

09/665690

Inventors:

David Leach - Niskayuna NY
Peter Allen Bergendahl - Scotia NY

Assignee:

General Electric Company - Schenectady NY

International Classification:

F01D 2526

US Classification:

415138, 415139

Abstract:

Circumferentially spaced arrays of support pins are disposed through access openings in an outer turbine shell and have projections received in recesses in forward and aft sections of an inner turbine shell supported from the outer shell. The projections have arcuate sides in a circumferential direction affording line contacts with the side walls of the recesses and are spaced from end faces of the recesses, enabling radial and axial expansion and contraction of the inner shell relative to the outer shell. All loads are taken up in a tangential direction by the outer shell with the support pins taking no radial loadings.

US Patent:

6590370, Jul 8, 2003

Filed:

Oct 1, 2002

Appl. No.:

10/261823

Inventors:

David H. Leach - Albany NY

Assignee:

MTI MicroFuel Cells Inc. - Albany NY

International Classification:

G05F 500

US Classification:

323299, 320101

Abstract:

This invention presents a method and apparatus for controlling the operating point, i. e. the output voltage or current, of a fuel cell to a desired value, efficiently transferring the available fuel cell power to a rechargeable battery and load, and isolating the fuel cell from the battery and load. Active control of the operating point of the fuel cell allows for optimized power output and fuel cell efficiency. This invention uses feedback from the input to regulate the input voltage or current. The output of the DC-DC converter either charges the battery or helps the battery supply the load, and is maintained equal to the battery voltage as the output of the DC-DC converter is directly connected to the battery.

US Patent:

7306869, Dec 11, 2007

Filed:

Dec 2, 2003

Appl. No.:

10/726162

Inventors:

David H. Leach - Albany NY, US

Assignee:

MTI MicroFuel Cells Inc. - Albany NY

International Classification:

H01M 8/04

US Classification:

429 34, 429 23, 1376235

Abstract:

A wide-area electrostatically-actuated shutter is provided that includes a thin, flexible, diaphragm that is placed between two rigid electrode structures. In one embodiment of the invention, the diaphragm has a set of openings in it. These openings overlap with corresponding openings in one of the rigid electrodes such that when the diaphragm is contiguous to that electrode, the openings provide apertures through which vaporous fuel can flow. The opposite electrode does not have overlapping openings, thus it forms a seal that prevents gas or vapor from passing through it when the diaphragm is in contact with the opposite electrode. The shutter is actuated electrostatically by an associated driver that applies a voltage to the diaphragm such that when the high voltage is applied to the diaphragm, the diaphragm is attracted to the fixed electrode that is tied to ground. Alternatively, when is desired to place the shutter in the opposite position, the diaphragm is placed at ground, which, in turn, pulls it towards the fixed electrode that is at a high voltage, to adjust the shutter. The shutter can be rapidly opened and closed at a high frequency in a PWM mode or a PFM mode.

US Patent:

7745025, Jun 29, 2010

Filed:

Feb 14, 2006

Appl. No.:

11/353755

Inventors:

David H. Leach - Albany NY, US
Russel Marvin - Goshen CT, US

Assignee:

MTI Microfuel Cells Inc. - Albany NY

International Classification:

H01M 12/00
H01M 8/04
H01M 2/00
H01M 10/44
H02J 7/00
H02J 7/04

US Classification:

429 9, 429 22, 429 61, 429149, 320101, 320103, 320119, 320140

Abstract:

A power pack system for charging a set of isolated batteries is provided. In an illustrative embodiment of the invention, a single fuel cell, a single DC-DC converter and a single system controller device comprises the power-generation side of the power pack. A set of switches is used to connect the power-generation side of the Power pack to one of the isolated batteries in the power pack, thereby recharging that particular battery in the battery power pack set. A battery protection and powerpath control device communicates with the system controller to determine which switches are to be closed depending upon which battery requires recharging. During normal operation the switches will follow the direction from the system controller. If a fault is detected by the battery protection circuit, the protection circuit will take priority and turn off the appropriate switch(es).

US Patent:

20060141308, Jun 29, 2006

Filed:

Dec 23, 2004

Appl. No.:

11/021971

Inventors:

Juan Becerra - Altamont NY, US
Charles Carlstrom - Saratoga Springs NY, US
George Costantino - Schenectady NY, US
Robert Hirsch - Troy NY, US
David Leach - Albany NY, US

International Classification:

H01M 8/04
H01M 8/10
F28F 27/00
G05D 23/00

US Classification:

429024000, 429030000, 429013000, 165276000, 165287000

Abstract:

An integrated heat management assembly that is thermally coupled to a component requiring temperature control is provided. The integrated heat management assembly in one embodiment of the invention is a heat switch which includes two opposed surfaces, a first surface being a hot contact which is coupled to the component, and the second surface being a cold contact which is coupled to a heat sink. An actuator which may be a phase changing material, is mechanically coupled to one of the two surfaces such that when the component reaches a threshold temperature, the actuator is triggered to bring the two surfaces into contact. In this manner, the hot surface conducts heat to the cold surface which then delivers heat to the heat sink to thereby lower the temperature of the component. Other embodiments include heat pipes associated with the heat switch in order to further dissipate heat or to divert it to other areas of the component requiring temperature control. Corresponding techniques are provided in accordance with the method of the invention.

US Patent:

20070285048, Dec 13, 2007

Filed:

Jun 12, 2006

Appl. No.:

11/451293

Inventors:

David H. Leach - Albany NY, US
Russel Marvin - Goshen CT, US
Peter S. Opela - Lake Worth FL, US

International Classification:

H02J 7/00
H01M 10/46
H01M 16/00

US Classification:

320101, 320107, 429 7

Abstract:

A fuel cell-based powerpack for use with an electronic device that requires multiple voltages is provided. The power pack includes an interface between a direct oxidation fuel cell and one or more rechargeable batteries coupled to supply power to the electronic application device. The interface is connected to receive the output of the fuel cell and includes one or more DC-DC converters that not only boost power to said one or more batteries, but are further coupled to the electronic device such that the fuel cell can be used to directly provide one or more subvoltages, at required voltage rails, directly to said electronic device. The output voltage can also be linearly regulated if needed in a particular application.

US Patent:

42508100, Feb 17, 1981

Filed:

Sep 25, 1979

Appl. No.:

6/078976

Inventors:

Raymond L. Fowler - Boulder CO
David W. Leach - Lexington KY
Lowell T. Sloan - Fort Lauderdale FL

Assignee:

International Business Machines Corporation - Armonk NY

International Classification:

B41F 2104
B41F 2712

US Classification:

101410

Abstract:

A clamp for holding a flexible sheet on a rotary carrier tightens the grip on, and pulls, the sheet upon rotation of the carrier, as a result of centrifugal forces generated on two weights attached to two cooperating arms within the clamp. The magnitude of the grip-tightening force is dependent upon the mass of a grip-tightening weight attached to the clamp. The magnitude of the sheet-pulling force is dependent upon the mass of a sheet-pulling weight attached to the clamp. The clamp faces are mounted for concurrent movement along the periphery of the carrier to prevent tearing or other damage to the sheet when it is pulled as the carrier is rotated.