Abstract:
A rotor blade of a helicopter is presented. In an embodiment, the rotor blade includes a body; and a heating mat arranged in the body and configured to supply heat to said body. The heating mat includes a first plurality of fibers and a second plurality of fibers electrically connected to the first plurality of fibers. The first plurality of fibers define a positive angle smaller than about +45° relative to a first direction perpendicular to a longitudinal direction of the body. The second plurality of fibers define a negative angle greater than about -45° relative to the first direction.
Abstract:
An assembly for providing flexure to a blade of a rotary blade system, the assembly including an upper support plate (22) having an upper curved surface (37) , a lower support plate (24) having a lower curved surface (37) , and a yoke (120) positioned therebetween. At least one of the upper and lower yoke surfaces (37) having a layer of cushioning material (56) positioned thereon and secured thereto. The layer of cushioning material (56) extending along and following the general contour of yoke surface (37) , and the layer of cushioning material (56) directly contacting a support plate (22,24) . Another embodiment is an assembly for providing flexure to a blade of a rotary blade system, including, an upper support plate (22) having an upper curved surface (27) , a lower support plate (24) having a lower curved surface (37) , and a yoke (120) positioned therebetween and directly contacting the support plates wherein one of the curved surfaces (37) is a non-circular arc that does not form part of the circumference of a circle.
Abstract:
A rotor blade of a helicopter is presented. In an embodiment, the rotor blade (100) includes a body (105) ; and a heating mat (301) arranged in the body (105) and configured to supply heat to said body. The heating mat (301) includes a first (505) plurality of fibers (400) and a second (510) plurality of fibers (400) electrically connected to the first plurality of fibers. The first plurality of fibers define a positive angle smaller than about +45° relative to a first direction perpendicular to a longitudinal direction of the body. The second plurality of fibers define a negative angle greater than about -45° relative to the first direction.
Abstract:
A structural joint includes a first member having a first base portion and a first leg portion. The structural joint further includes a second member having a second base portion and a second base portion. The first base portion and the second base portion are coupled together at an overlapping portion. The first leg portion and the second leg portion form a cavity for structurally coupling to a structural member.
Abstract:
A present system of the present application provides for reticulating adhesive to the surface network of cellular core. As such, the present invention allows for substantial improvements over prior systems. The present invention may be implemented with any aircraft, wind turbine, rocket, space satellite, or land vehicle, but there is nothing within the spirit and scope of the present invention limiting it to any particular application. The teachings of the present invention are useful to any composite structure utilizing cellular core.
Abstract:
A method of making a rotor yoke includes preparing a cured composite rotor yoke preform on a single-sided curing tool and machining at least one portion of the cured rotor yoke preform to form a rotor yoke. In one embodiment, preparing the cured composite rotor yoke is accomplished by applying successive layers of uncured polymeric composite material to a single-sided tool in a configuration to produce an uncured rotor yoke preform; disposing a semi-rigid caul to an untooled side of the uncured rotor yoke preform; enclosing the uncured rotor yoke preform and the semi-rigid caul by substantially hermetically sealing a vacuum bag to the tool; substantially evacuating a volume defined by the vacuum bag and the tool of air; and heating the uncured rotor yoke preform, sometimes under pressure, to form the cured composite rotor yoke preform.
Abstract:
A helicopter rotor blade includes a structural composite skin defining a cavity therein; a composite spar disposed within the cavity and adhesively bonded to the skin, a portion of the spar exhibiting a C-shape in cross section; and a foam core disposed within the cavity and adhesively bonded to the skin. The structural composite skin forms an external, closed box structure configured to transmit mechanical loads encountered by the rotor blade.
Abstract:
A composite core includes a plurality of tubes, each the plurality of tubes comprising a plurality of fibers disposed in a polymeric matrix. Adjacent tubes of the plurality of tubes are adhesively bonded to one another along sides of the adjacent tubes. A method of making a composite core includes the steps of providing a plurality of tubes, each of the plurality of tubes including a plurality of fibers disposed in a polymeric matrix, and adhesively bonding adjacent tubes of the plurality of tubes along sides of the adjacent tubes. A method of making a composite core such that a removable band is included in the core, the removable band being configured to be removable through a procedure subsequent to the cure of the composite core, thereby producing gaps in the core.
Abstract:
An assembly for providing flexure to a blade of a rotary blade system, the assembly including an upper support plate having an upper curved surface, a lower support plate having a lower curved surface, and a yoke positioned therebetween. At least one of the upper and lower yoke surfaces having a layer of cushioning material positioned thereon and secured thereto. The layer of cushioning material extending along and following the general contour of yoke surface, and the layer of cushioning material directly contacting a support plate. Another embodiment is an assembly for providing flexure to a blade of a rotary blade system, including, an upper support plate having an upper curved surface, a lower support plate having a lower curved surface, and a yoke positioned therebetween and directly contacting the support plates wherein one of the curved surfaces is a non-circular arc that does not form part of the circumference of a circle.