A flexible coupling for transmitting torque between parts of a transmission shaft system comprises a tubular section of continuous-fibre-reinforced composite material which has been modified to form a living hinge section with reduced bending stiffness to allow flexion of the tubular section. The tubular section may be modified through the provision of a pattern of formations within the living hinge section. The formations may be in the form of apertures and/or recesses in the continuous-fibre-reinforced composite material to create a plurality of living hinges in the material between, in particular slots and/or grooves.

The invention relates to a strut, such as fiber composite struts used in aircraft or spacecraft, which has a largest possible outer diameter within a cylindrical installation space of the strut. The invention concerns an insert connected to a fiber composite hollow structure, such as a fiber plastic composite hollow structure, where the hollow structure engages an undercut of the insert, wherein the outer region of the fiber composite hollow structure likewise has an undercut and this undercut is filled with a fiber composite jacket, such as a fiber plastic composite jacket, and the inner region of the fiber composite hollow structure has, at least in one subregion, a core connected thereto.

A drive shaft has a central tubular portion formed of a polymer composite with imbedded fibers. It extends between a first end and a second end. The central tubular portion has an outer peripheral surface. There is at least one ring on the outer peripheral surface of the central tubular portion. A method of repairing a composite material tube includes the steps of (a) identifying a damaged area on a composite tube, and (b) placing a patch on a surface of the tube and over the damaged area.

A tube arrangement includes a composite tube defining a centerline axis, wherein the composite tube comprises a proximal surface and a distal surface, and an end fitting comprising a first end disposed within the composite tube and a second end extending from the composite tube, wherein an outer surface of the end fitting defines a flared portion defining a terminus of the first end, a lobe portion disposed axially from the flared portion, and a terminating portion disposed axially from the lobe portion, the proximal surface conforms to a geometry of the outer surface of the end fitting, the lobe portion and the flared portion mechanically lock the end fitting to the composite tube to mitigate movement of the end fitting relative to the composite tube.

A composite vehicle driveshaft assembly includes a composite tube and a yoke bonded to one of the ends of the tube. The yoke has an inner sleeve that is concentrically received in the end of the tube. The sleeve has an outer peripheral surface that faces the inner peripheral surface of the tube with a cavity formed therebetween. An adhesive injection passage is formed in the yoke and extends at an acute angle from an inlet that is formed in an axial surface of the yoke to an outlet that is formed in the outer peripheral surface of the sleeve and that opens into the cavity. Also disclosed is a method of bonding a yoke of such a driveshaft assembly to a composite tube.

A shaft component, which in particular can be connected or is connected to the input or output side of a gear box in a gas turbine engine, in particular an aircraft engine, wherein the shaft component has at least two regions comprising fiber reinforced plastic, with fibers in the at least two regions differing in their composition, their geometric properties, their density, their radial position, their axial position and/or in their fiber orientation in the shaft component.

A drive shaft extends between axial ends and has at least one portion through which an outer diameter of the drive shaft changes through an infinite number of diameters, with the at least one portion extending across at least 15% of an axial distance between the axial ends of the drive shaft. A drive shaft with a generally spiral undulation at its outer periphery is also disclosed.

A drive shaft body extends between axial ends and has an outer peripheral surface with undulations extending between relatively greater and smaller outer diameters. The undulations extend along a non-zero angle relative to a circumferential direction defined relative to a drive axis of the drive shaft. The undulations extend along a spiral. The drive shaft body is formed of a fiber-reinforced composite material.

A flexible coupling for transmitting torque between parts of a transmission shaft system comprises a tubular section of continuous-fibre-reinforced composite material which has been modified to form a living hinge section with reduced bending stiffness to allow flexion of the tubular section. The tubular section may be modified through the provision of a pattern of formations within the living hinge section. The formations may be in the form of apertures and/or recesses in the continuous-fibre-reinforced composite material to create a plurality of living hinges in the material between, in particular slots and/or grooves.

A drive shaft has a tubular member extending between axial ends and being hollow. The tubular member is formed of a thermoplastic matrix with embedded fibers. At least one ring member is positioned radially of the tubular member. A method is also disclosed.