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 filament wound composite fibre reinforced polymer shaft comprising helical wound fibres, the shaft having at least one hole perpendicular to an axis of the shaft; wherein fibre paths of the helical wound fibres divert around the hole. The hole can be used as an attachment point to connect the shaft to other parts, e.g. by means of a pin passed directly through the hole. The amount of metal used in this type of connection can be significantly reduced compared to using metal end fittings, thus greatly reducing cost and weight of the whole system. Fibres are diverted around the hole rather than the hole being cut through the fibres which would reduce the strength of the shaft as a whole. By diverting the fibres around the hole, the fibres retain their load bearing properties and the strength of the shaft is maintained even in the presence of the hole.

A drive shaft is for selectively connecting a drive input to an output. The drive shaft has a tubular portion, a first diaphragm member, and a second diaphragm member displaced axially along the shaft from the first diaphragm member. The first and second diaphragm members each are formed with two axial ends. At least one undulation extends radially of the ends. The tubular portion connects the first and second diaphragm members. The first and second diaphragm members and the tubular portion are formed of fiber-reinforced polymer matrix composites. The first and second diaphragm members are connected to first and second axial ends of the tubular portion through a mechanical connection at joints. There is also a method of forming a drive shaft.

A low surface-roughness part is formed at a first tapered part, as a result, the roughness of an opening-edge of a groove part of an internal spline part that opens at the first tapered part is reduced, and surface pressure applied by the opening edge to a tooth of an external spline part can be reduced. As a result, the opening edge of the groove part of the internal spline part can be kept from digging into the tooth, and variation, between products, in the insertion load of a second shaft part can be suppressed.

An anti-resonance apparatus of a propeller shaft may include a support provided in a tube and configured to be rotated with the tube, and including at least a guide pin arranged at equal angles around a longitudinal axis of the tube and formed in a radial direction of the support, at least a mass body slidably engaged to the at least a guide pin and guided by the at least a guide pin to be moved along a longitudinal axis of the at least a guide pin, and a return spring configured to provide an elastic force in a moving direction in which the at least a mass body is moved toward the support.

A drive shaft made from composite materials that comprises a hollow body and a flange that is integrally formed with the hollow body. The hollow body is adapted to rotating around an associated rotation axis and is made of a first composite material. The flange is made of a second composite material and arranged at an axial end of the hollow body. The flange comprises at least two separate plates that branch out from the hollow body at the axial end. The flange further comprises a mounting section that is configured to be mounted to an external component and comprises a plurality of holes that is adapted to accommodate coupling means.

A drive shaft made from composite materials that comprises a hollow body and a flange that is integrally formed with the hollow body. The hollow body is adapted to rotating around an associated rotation axis and is made of a first composite material. The flange is made of a second composite material and arranged at an axial end of the hollow body. The flange comprises at least two separate plates that branch out from the hollow body at the axial end. The flange further comprises a mounting section that is configured to be mounted to an external component and comprises a plurality of holes that is adapted to accommodate coupling means.

A process for forming a flexible composite driveshaft includes providing a mandrel having a rigid region and a compressible region, applying fiber tape to the mandrel using automated fiber placement with in-situ laser curing in the rigid region and without in-situ laser curing the compressible region, and compressing the fiber tape and compressible material in the compressible region to form diaphragms that extend radially outward to a diameter that is at least twice the size of a diameter of the composite driveshaft in the rigid region.

An assembly includes a composite body and a load body connected to the composite body by a fastener. The composite body is elongate along a body axis and has a first fastener opening extending radially therethrough. The load body has a second fastener opening extending therethrough. The fastener extends along an insertion axis through the first fastener opening and the second fastener opening to connect the composite body and the first load body together. The fastener has a non-circular cross-section orthogonal to the insertion axis.

A power transmission shaft includes a metal shaft member, and a resin shaft member connected to the metal shaft member in an axial direction of the power transmission shaft. The resin shaft member is made of fiber reinforced plastic. The metal shaft member and the resin shaft member are joined to each other through a close-contact fitting portion between a male spline, which is formed in an outer surface of the metal shaft member, and a female spline formed by press-fitting the male spline into the resin shaft member. An edge is formed at a radially outer edge portion of a press-fitting-start end surface of the male spline of the metal shaft member.