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 composite/metal joint includes a composite member, a metallic member, a cylindrical liner, and a fastener. The composite member has a first aperture. The metallic member is disposed adjacent to the composite member and has a second aperture coaxially aligned with the first aperture. The cylindrical liner extends longitudinally from a first end to a second end. The cylindrical liner has a cylindrical outer liner surface and a longitudinally extending third aperture coaxial with the first and second apertures and defined by an inner liner surface. The cylindrical liner is disposed in the first and second apertures with the outer liner surface adjacent to aperture walls of the first and second apertures. The cylindrical liner has a plurality of grooves intersecting the outer liner surface. The fastener is disposed through the third aperture of the cylindrical liner and is configured to attach the metallic member to the composite member. An outer surface of the fastener is in direct contact with the inner liner surface.

An easily inspected shaft assembly is provided and includes a shaft, a sleeve receptive of a portion of the shaft and an optically activatable layer including first and second sections disposed on respective exterior surfaces of the shaft and the sleeve, respectively, such that the first and second sections move relative to one another as the shaft and the sleeve move relative to one another.

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.

A joint structure includes a first member configured to be connected rotatably to a mating member, and a second member configured to be connected rotatably to an actuator for driving the mating member. Each of the first and second members has one or more ridge portions that extend circumferentially along an outer peripheral surface. The joint structure further includes a core shaft connecting the first member and the second member, and a covering member provided tightly thereon to cover the core shaft, the one or more ridge portions of the first member, and the one or more ridge portions of the second member.

A composite shaft with an end fitting mounted on one end of said shaft and a preload structure arranged to provide a biasing force to bias the composite shaft against the end fitting. The end fitting has a first interface surface, the first interface surface being tapered at an angle to the shaft axis and the shaft has a second interface surface for engagement with the first interface surface and is tapered at an angle to the shaft axis, the second interface surface extending axially from a first end to a second end, the shaft being thicker at the second end than at the first end. The shaft has a third interface surface and the preload structure has a fourth interface surface and the contact pressure of the third interface against the fourth interface increases from the first end of the shaft to the second end of the shaft.

A mechanical part configured to be placed under torque. The mechanical part includes an inner tube having, a corrugated web, and an outer shell. The inner tube has an outer tube circumference, a tube axial direction, and a tube length. The corrugated web has a plurality of peaks and a plurality of troughs, a height measured as a difference between one of the peaks and one of the troughs, and a web length perpendicular to the height and in the tube axial direction. The outer shell has an inner shell circumference, an outer shell circumference, and a shell length. The plurality of troughs is affixed to the outer circumference of the inner tube. The plurality of peaks is affixed to the inner shell circumference of the outer shell. The web length is aligned with the tube length and the shell length.

A method for producing by pultrusion a hollow main body of a rotary movement transmission shaft made of a composite material, the method including: impregnating a reinforcement; arranging a reinforcing fabric around a pultrusion chuck to wrap the pultrusion chuck, the fabric including circumferential fibers arranged in planes orthogonal to a longitudinal axis of the chuck; and then depositing the impregnated reinforcement around the reinforcing fabric.

The method includes producing an initial preform on a mandrel by filament winding without generating shrinking, cutting the initial preform to the correct length, placing the assembly provided beforehand with internal drainage device and pressurization device into a female mold, and bringing the preform assembly to a softening temperature and pressurizing the assembly at both ends until it is deformed by a diametrical increase in its dimensions. The method further includes bringing the impregnation resin to polymerization temperature and pressure in order to allow the workpiece to consolidate, its external shape becoming consistent with the internal shape of the mold, opening the mold and removing the workpiece from the mold, and machining the final shapes of the composite workpiece.

A corrugated portion is formed in one end edge portion of the metallic shaft main body (2), and a triangular corrugated portion (11) is formed in an end edge portion of the shaft auxiliary body (3) on the metallic shaft main body side. The metallic shaft main body (2) and the shaft auxiliary body (3) are integrated by being linearly arranged by way of meshing that brings a side of the triangular corrugated portion (9) on the main body side and a side of the triangular corrugated portion (11) on the auxiliary body side into contact with each other. A fiber orientation angle (θ) of the fiber reinforced plastic of the shaft auxiliary body (3) is set so as to be in the same direction as a direction of stress generated in a hypotenuse of each triangular portion under a torque load state.