Described are novel composite structural panels and methods of forming such panels. In some examples, a method comprises wrapping a mandrel with a composite tape to form a composite tube. This wrapping operation allows forming composite tubular structures with any cross-sectional profiles defined by the mandrel. The wrapping is also used to control the fiber orientations in the composite tubular structures. The composite tube is then cut into composite tubular structures. In some examples, the composite tube is partially cured prior to the cutting, which allows removal of the mandrel while preserving the shape of the composite tube. This cutting operation allows forming composite tubular structures with different lengths, shapes, and orientations of the ends. The composite tubular structures are disposed on a support structure and are bonded to each other. In some examples, this bonding operation also involves final curing of the composite tubular structures.

A method and apparatus for fabricating a composite structure. The method comprises defining a shape for the composite structure with a first face sheet. The method places core sections on the shape defined by the first face sheet. The method places an adhesive in a group of joint cavities. The method places a second face sheet on the core sections placed on the first face sheet, wherein the first face sheet, the core sections, and the second face sheet, define a structural assembly in which the group of joint cavities are present. The method cures the structural assembly with the adhesive in the group of joint cavities to fabricate the composite structure in which the adhesive fills the group of joint cavities when the adhesive is cured.

A motor vehicle roof shell having a rigid composite component having an inner side facing a vehicle interior, and an acoustic insulation layer disposed on the inner side of the composite component. The panel-type rigid composite component has at least one tray-like recess on its inner side, said recess being filled with an open-pored foam material which forms the acoustic insulation layer and whose surface is flush with a surface of the composite component surrounding the recess. A motor vehicle roof shell motor vehicle having a panel-type rigid composite component having an inner side, which faces the vehicle interior, and an acoustic insulation layer disposed on the inner side of the composite component, wherein the acoustic insulation layer is formed by at least one rigid-foam or semi-rigid-foam plate which is bonded to the inner side of the composite component and compressed that its volume is reduced compared to preassembly state.

A method and apparatus for fabricating a composite structure. The method comprises defining a shape for the composite structure with a first face sheet. The method places core sections on the shape defined by the first face sheet. The method places an adhesive in a group of joint cavities. The method places a second face sheet on the core sections placed on the first face sheet, wherein the first face sheet, the core sections, and the second face sheet, define a structural assembly in which the group of joint cavities are present. The method cures the structural assembly with the adhesive in the group of joint cavities to fabricate the composite structure in which the adhesive fills the group of joint cavities when the adhesive is cured.

Systems and methods are provided for blade-and-slot panel affixation. One embodiment is a method. The method includes cutting a first slot into a first composite panel that includes a core between two facesheets. The first slot penetrates through the core of the first composite panel. The method also includes cutting a second slot into a second composite panel that includes a core between two facesheets. The second slot penetrates through a facesheet of the second composite panel as well as the core of the second composite panel. The method further includes inserting a blade into the first slot, and inserting the blade into the second slot.

Methods for reworking structures and reworked cellular core panels, reworked structures comprising the reworked cellular core panels, and guides and cutting apparatuses for reworking cellular acoustic panels and reworking cellular acoustic and non-acoustic panels are disclosed.

A plastic component having a core that has a thermoset matrix and an add-on part anchored to the core. At least the securing region of the add-on part can be formed from a thermoplastic and is secured by the securing region to the core of the plastic component, the securing region being attached to the core or inserted or pressed into the core, bonding, in a fusible state produced by the application of energy, in particular by ultrasonic vibrations, with the core and being anchored thereto or therein after solidification, in particular, as a connection anchor.

A motor vehicle roof shell having a rigid composite component having an inner side facing a vehicle interior, and an acoustic insulation layer disposed on the inner side of the composite component. The panel-type rigid composite component has at least one tray-like recess on its inner side, said recess being filled with an open-pored foam material which forms the acoustic insulation layer and whose surface is flush with a surface of the composite component surrounding the recess. A motor vehicle roof shell motor vehicle having a panel-type rigid composite component having an inner side, which faces the vehicle interior, and an acoustic insulation layer disposed on the inner side of the composite component, wherein the acoustic insulation layer is formed by at least one rigid-foam or semi-rigid-foam plate which is bonded to the inner side of the composite component and compressed that its volume is reduced compared to preassembly state.

The invention relates to a dowel for arranging in lightweight building boards, wherein a lightweight building board has a first cover layer and a second cover layer made of compact, pressure-resistant material and, arranged between the cover layers, a core layer made of material having a lower density than the cover layers, comprising a first dowel part and a second dowel part, wherein the first and the second dowel part are designed to be displaceable relative to one another, in which dowel the first dowel part and the second dowel part each have at least two fingers which extend parallel to a longitudinal direction of the dowel, wherein, in the plugged-together state of the first and second dowel part, the fingers of the first dowel part and the fingers of the second dowel part inter-engage at least in certain portions.

A method of anchoring a connector in a heterogeneous first object that includes a first building layer and, distally of the first building layer, an interlining layer. The method includes providing the first object and the connector, which includes thermoplastic material in a solid state; contacting the connector with the first building layer; applying a first mechanical pressing force to the connector until the first building layer is pierced by the connector and a distal portion of the connector reaches into the interlining layer; applying a second mechanical pressing force and mechanical vibration to the connector until a flow portion of the thermoplastic material is flowable and penetrates structures of the first object, and a distally facing abutment face of the head portion abuts against the metal profile in a region next to the opening; and letting the thermoplastic material resolidify to yield a positive-fit connection.