Smooth surface possessing fatigue strength - has regularly shaped protuberances on it with square base surface

摘要

The surface (4) possessing fatigue strength has a smooth, convex surface from which protrude regularly shaped protuberances. The sides of each protruberance form a four sided pyramid plane at right angles to the surface and containing all the surface normals of the side surface. The side surface forms an intersecting line. The protuberances have a square base surface and are positioned in a draught board formation. These are grooves in the pyramids and the curved surfaces at the bases of thepyramids the pyramids fulfil a given mathematical relationship. USE/ADVANTAGE - Possible notch stresses on the surface are minimised and the surface joined to the material.