David C Hunter

US Patent:

6568906, May 27, 2003

Filed:

Apr 24, 2001

Appl. No.:

09/841676

Inventors:

Simon J. Gharibian - New Haven CT
David H. Hunter - Cheshire CT

Assignee:

Sikorsky Aircraft Corporation - Stratford CT

International Classification:

B64C 1128

US Classification:

416 88, 384 42

Abstract:

A conformal bearing assembly includes an bearing housing, an elastomeric member and a bearing element. The bearing assembly is mounted between and inner and outer telescopic member. The elastomeric member allows the bearing element to substantially conform to the adjacent telescopic member irrespective of minor manufacturing inconsistencies along the adjacent telescopic member. Contact pressure between the bearing element and the adjacent telescopic member is thereby more evenly distributed which minimizes regions of interference and or clearance which may otherwise result in undesirable wear characteristics of the telescopic system.

US Patent:

7695249, Apr 13, 2010

Filed:

Dec 1, 2006

Appl. No.:

11/565669

Inventors:

Timothy A. Krauss - Harwinton CT, US
Pedro L. Cabrera - West Haven CT, US
David H. Hunter - Cheshire CT, US

Assignee:

Sikorsky Aircraft Corporation - Stratford CT

International Classification:

B64C 27/32

US Classification:

416134A, 416226

Abstract:

A bearingless rotor system includes a flexbeam assembly having a first beam and a second beam arranged in a back-to-back orientation with a pitch shaft channeled therebetween. The beams morph into a rotor blade spar at an outboard rotor blade station. The outboard section of the flexbeam assembly receives the full pitch input from the pitch shaft while the most inboard section of the flexbeam assembly is essentially fixed in pitch by a blade attachment to a rotor hub assembly. The flexbeam assembly twist versus span is essentially linear from the most inboard to the most outboard rotor blade stations. The outboard rotor blade station, being attached to the outboard section of the flexbeam assembly, thereby also defines the pitch input equivalent from the outboard rotor blade station to the rotor blade tip.

US Patent:

20120201678, Aug 9, 2012

Filed:

Feb 8, 2012

Appl. No.:

13/368795

Inventors:

David H. Hunter - Cheshire CT, US
Ryan Thomas Casey - West Haven CT, US
Francis Edward Byrnes - White Plains NY, US

Assignee:

SIKORSKY AIRCRAFT CORPORATION - Stratford CT

International Classification:

B64C 11/12

US Classification:

416134 A

Abstract:

A rotor hub assembly for a helicopter includes a rotor hub operably connectible to a shaft of a helicopter. One or more flex beams extend through the rotor hub, with each end of each flex beam operably connectible to a rotor blade. One or more inner bearings are located at the rotor hub to spherically support the one or more flex beams in the rotor hub. A rotor assembly for a helicopter includes a rotor hub operably connectible to a shaft of a helicopter. One or more flex beams extending through the rotor hub and one or more inner bearings are located at the rotor hub to spherically support the one or more flex beams in the rotor hub. A plurality of rotor blades are operably connected to the ends of the one or more flex beams.

US Patent:

20130064674, Mar 14, 2013

Filed:

Sep 13, 2011

Appl. No.:

13/231600

Inventors:

David H. Hunter - Cheshire CT, US
Ryan T. Casey - West Haven CT, US
Francis E. Byrnes - White Plains NY, US

Assignee:

SIKORSKY AIRCRAFT CORPORATION - Stratford CT

International Classification:

B64C 27/473

US Classification:

416226

Abstract:

A rotor for use in an aircraft includes an inner hub; and a plurality of blades arranged around the inner hub, each of the plurality of blades comprising an inner structural member; an outer blade shell surrounding the inner structural member; and a centering block located at a base of the inner structural member proximal to the inner hub, wherein the centering block is located between a first lateral portion of the inner structural member and a second lateral portion of the inner structural member, wherein the centering block is further connected to the outer blade shell, and wherein the centering block allows the outer blade shell to rotate about an axis approximately corresponding to the inner structural member.

US Patent:

56014082, Feb 11, 1997

Filed:

Mar 18, 1996

Appl. No.:

8/617458

Inventors:

David H. Hunter - Cheshire CT
Francis E. Byrnes - White Plains NY
Douglas E. Tritsch - Beavercreek OH

Assignee:

Sikorsky Aircraft Corporation - Stratford CT

International Classification:

B64C 2735

US Classification:

416134A

Abstract:

An axisymmetric elastomeric bearing assembly (30) for an articulated rotor hub assembly (10), which axisymmetric elastomeric bearing assembly (30) is disposed in combination with a rotor assembly yoke (24) and hub retention member (12) of the rotor hub assembly (10) and is operative for accommodating the multi-directional displacement of a rotor blade assembly (14) thereof. The axisymmetric elastomeric bearing assembly (30) includes a central bearing element (32) having a spherical bearing surface (32s) defining a bearing focal point (30f) and spherical elastomeric elements (34) bonded to the spherical bearing surface (32s) on opposing sides of the bearing focal point (30f). Each of the spherical elastomeric elements (34) have a plurality of alternating layers of elastomer and nonresilient shims (36, 38) which have a center of curvature which is coincident with the bearing focal point (30f) and disposed at increasing radii therefrom. Bearing endplates (40) are bonded to the spherical elastomeric elements (34) and are mounted in combination with the yoke (24) and hub retention member (12). In operation, the central bearing element (32) is rotationally self-positioning to effect load and motion sharing between the spherical elastomeric elements (34).

US Patent:

60741260, Jun 13, 2000

Filed:

Oct 17, 1997

Appl. No.:

8/953744

Inventors:

David H. Hunter - Cheshire CT
Francis E. Byrnes - White Plains NY
Kevin S. French - Trumbull CT

Assignee:

Sikorsky Aircraft Corporation - Stratford CT

International Classification:

F16D 100

US Classification:

403404

Abstract:

A structural interlock (40) for inhibiting relative rotation between mating elements (20, 42) characterized by a plurality of grooves (50) being formed in one of the mating elements, and a mechanism (60) for producing a nominal contact pressure on the contact area (A. sub. 1 thru A. sub. 8) between the mating element, which contact pressure elastically deforms the other of the mating elements into the grooves (50), and is less than the material yield strength of either of the mating elements. In the preferred embodiment, the grooves (50) are radially oriented and an applied compressive load produces a nominal contact pressure which is about 80% of the material yield strength.

US Patent:

53642309, Nov 15, 1994

Filed:

Jun 22, 1992

Appl. No.:

7/903061

Inventors:

Timothy A. Krauss - Harwinton CT
David H. Hunter - Cheshire CT
Robert D. Beatty - Trumbull CT

Assignee:

United Technologies Corporation - Hartford CT

International Classification:

B64C 2733

US Classification:

416134A

Abstract:

A rotor blade subassembly for a rotor assembly having ducted, coaxial counter-rotating rotors includes a flexbeam, an integrated torque tube/spar member, and an aerodynamic fairing or rotor blade. The flexbeam is a laminated composite structure that reacts centrifugal loads and a majority of the bending loads of the rotor assembly. The flexbeam has a spanwise predetermined linear twist so that the pretwisted flexbeam is unstrained during specified forward flight conditions. The integrated torque tube/spar member is formed as a continuous, filament wound tubular composite structure having high torsional and bending stiffness that provides a continuous torsional load path and facilitates load coupling between the rotor blade and the pretwisted flexbeam. The spar segment of the functions as the primary structural member of the rotor blade subassembly and, is operative to react all bending, torsional, shear, and centrifugal dynamic loads of the rotor assembly. The torque tube segment reacts all torsional loads and some of the bending loads of the rotor assembly.

US Patent:

56454007, Jul 8, 1997

Filed:

Mar 18, 1996

Appl. No.:

8/617012

Inventors:

David H. Hunter - Cheshire CT
Karl B. Scherer - Stratford CT

Assignee:

Sikorsky Aircraft Corporation - Stratford CT

International Classification:

B64C 2737
B64C 2735

US Classification:

416134A

Abstract:

A composite cuff structure (40) for mounting the root end (14e) of a rotor blade assembly (14) to the radial arms (24a, 24b) of a rotor assembly yoke (24) and for accommodating a twist disparity therebetween. The composite cuff structure (40) is generally tubular in shape and is fabricated from a composite material having reinforcing fibers (70) disposed in a binding matrix. The composite cuff structure (40), furthermore, includes a blade-receiving sleeve portion (42), a yoke mounting portion (44), spanwise fold portions (46) and sidelobe portions (48), which portions (42, 44, 46, 48) are structurally integrated to form a unitary body. The blade-receiving sleeve portion (42) is disposed in combination with the root end (14e) of the rotor blade assembly (14) and includes first and second blade mounting segments (42a, 42b), which define a rotor blade attachment plane P. sub. B. The yoke mounting portion (44) is disposed in combination with the radial arms (24a, 24b) of the rotor assembly yoke (24) and includes fore and aft pairs (44-1, 44-2) of first and second yoke mounting segments (44a, 44b) defining a yoke attachment plane P. sub. Y. The pairs (44-1, 44-2) of yoke mounting segments (44a, 44b) are, furthermore, disposed laterally of the blade mounting segments (42a, 42b).