Composite honeycomb core structures and single stage hot bonding method of producing such structures

Abstract

Composite honeycomb core structures, such as airplane control surface structures, capable of withstanding bending and shear stresses, are disclosed along with a single stage hot bonding process of manufacturing such structures. The composite structures include: a primary load carrying member formed of a high density honeycomb core, two spar caps, each having a predetermined thickness, bonded to opposing surfaces of the high density honeycomb core; a low density honeycomb core bonded to the high density honeycomb core along one edge thereof; and, a skin superposed on, and bonded to, the spar caps and the low density honeycomb core. (In some cases, depending upon the structural strength needed, the high density honeycomb core may be replaced by a low density honeycomb core and formed in a unitary manner with the low density honeycomb core to which the skin is bonded. Or, both can be high density honeycomb cores formed in a unitary manner and machined to the desired shape.) The single stage hot bonding process includes the steps of bonding a low density honeycomb core to a high density honeycomb core, shaping the combined honeycomb core, adhesively attaching spar caps to opposing surfaces of the high density honeycomb core, adhesively attaching a skin to the spar caps and the low density honeycomb core and curing the composite structure in a heated bag mold.

Dependencies are inferred from the claim text.