초록 ▼

A method of making hollow aircraft rotor blades from laminated material. An expandable mandrel is first made from curable materials and then a composite build-up of epoxy material is made by layering a plurality of prepreg plies of curable material over the expandable mandrel. The mandrel and build-

A method of making hollow aircraft rotor blades from laminated material. An expandable mandrel is first made from curable materials and then a composite build-up of epoxy material is made by layering a plurality of prepreg plies of curable material over the expandable mandrel. The mandrel and build-up of epoxy materials are then placed in a mold and pressure is applied to expand the mandrel which, in turn, expands the build-up of material against the mold. The mandrel and composite build-up of material are then cured and the mandrel becomes an integral part of the rotor blade.

대표청구항 ▼

A method of making a section of a hollow aircraft rotor blade comprising the steps of: forming a hollow expandable mandrel by connecting an upper skin panel, a lower skin panel, a leading edge channel and an aft channel, said panels and channels being of resin reinforced curable materials which are

A method of making a section of a hollow aircraft rotor blade comprising the steps of: forming a hollow expandable mandrel by connecting an upper skin panel, a lower skin panel, a leading edge channel and an aft channel, said panels and channels being of resin reinforced curable materials which are cemented together, then laying a plurality of prepreg plies of curable material onto said hollow expandable mandrel to form a composite build-up, then placing said hollow expandable mandrel with said plurality of prepreg plies thereon in a female mold, then placing a pressure diaphragm inside said hollow mandrel which applies pressure to the inside of said hollow mandrel which, in turn, expands and transmits uniform pressure to said composite build-up, then curing said mandrel and build-up whereby said mandrel becomes an integral part of said aircraft rotor blade.