David K Welch

US Patent:

6345141, Feb 5, 2002

Filed:

Dec 5, 2000

Appl. No.:

09/730168

Inventors:

Stephen G. Grubb - Columbia MD
David F. Welch - Menlo Park CA

Assignee:

SDL, Inc. - San Jose CA

International Classification:

G02B 602

US Classification:

385127, 372 6

Abstract:

A double-clad optical fiber has an inner cladding that has a torsional stress induced within it during manufacture. By rotating the fiber preform before curing of the inner cladding layer, a physical stress may be permanently imparted to the inner cladding that interacts with pump energy within the inner cladding layer to encourage mode mixing. As the cladding modes are disturbed by the stresses in the fiber, they are redirected so that the light in them intersects the core.

US Patent:

20130283821, Oct 31, 2013

Filed:

Apr 30, 2012

Appl. No.:

13/459831

Inventors:

Jonathan Gilson - West Hartford CT, US
Molly M. May - Manchester CT, US
David A. Welch - Quaker Hill CT, US
Nigel David Sawyers-Abbott - South Glastonbury CT, US

International Classification:

F02C 3/04
F04D 29/66

US Classification:

60805, 415119

Abstract:

A nacelle structure for a gas turbine engine assembly includes a fan case, an inlet, and a noise attenuation device. The fan case is configured to be disposed about a fan section of the gas turbine engine, which fan section has a diameter D. The inlet is attached to the fan case and extends axially forward of the fan case. A hilite of the inlet is spaced a distance L from a region in which the fan section is configured to be disposed. A ratio L/D is less than about 0.6. The noise attenuation structure covers a portion of an inner surface of the fan case and the inlet.

US Patent:

61577634, Dec 5, 2000

Filed:

Mar 30, 1998

Appl. No.:

9/050386

Inventors:

Stephen G. Grubb - Columbia MD
David F. Welch - Menlo Park CA

Assignee:

SDL, Inc. - San JOse CA

International Classification:

G02B 622

US Classification:

385126

Abstract:

A double-clad optical fiber has an inner cladding with a cross-sectional shape that is non-circular, but that maintains a good end-coupling profile. The cross-sectional shape of the inner cladding is such that two perpendicular distances across the shape, each of which passes through a geometric center of a core of the fiber, are equal for all angular positions. Thus, while mode mixing within the inner cladding is enhanced, the inner cladding does not suffer any oblong distortions of its shape, and is therefore more easily coupled to conventional fibers. The cross-sectional cladding shape may include various regions along its outer surface that do not conform to a circular geometry about a center of the core. These regions may include flat regions, or concave or convex regions. The overall cross-sectional shape of the inner cladding may also be octagonal or star-shaped.

US Patent:

20200123905, Apr 23, 2020

Filed:

Oct 18, 2018

Appl. No.:

16/163690

Inventors:

- Farmington CT, US
James Glaspey - Farmington CT, US
David A. Welch - Quaker Hill CT, US

International Classification:

F01D 5/16
F01D 5/02

Abstract:

An airfoil for a gas turbine engine according to an example of the present disclosure includes, among other things, an airfoil section that extends from a root section. The airfoil section extends between a leading edge and a trailing edge in a chordwise direction and extends between a tip portion and the root section in a radial direction. The airfoil section defines a pressure side and a suction side separated in a thickness direction, and the airfoil section includes a metallic sheath that defines an internal cavity receiving a composite core. The root section defines at least one bore dimensioned to receive a retention pin. At least one damping element is received in the internal cavity and that selectively causes the airfoil section to stiffen.

US Patent:

20160131039, May 12, 2016

Filed:

Mar 12, 2014

Appl. No.:

14/771294

Inventors:

- Hartford CT, US
Andre Herman TROUGHTON - Windsor Locks CT, US
Brian J. BRESLIN - Palm Beach Gardens FL, US
Jesse Ian BERUBE - Simsbury CT, US
Christopher DURKEE - Westfield MA, US
David A. WELCH - Quaker Hill CT, US

International Classification:

F02C 7/18
F02C 7/14

Abstract:

A heat exchanger manifold for a gas turbine engine according to an exemplary aspect of the present disclosure includes, among other things, a manifold body extending between a first face and a second face, a first seal land defining a first fluid port extending through the manifold body between the first face and the second face, and a first seal received within the first fluid port.

US Patent:

20160032833, Feb 4, 2016

Filed:

Mar 12, 2014

Appl. No.:

14/774035

Inventors:

- Hartford CT, US
Mark W. Costa - Storrs CT, US
David A. Welch - Quaker Hill CT, US

International Classification:

F02C 7/045

Abstract:

A cartridge for a fan case of a gas turbine engine includes an inlet acoustic liner section integrated with a thermally conforming liner section.