Coiled valve spring with axial coils - has at least three corners with angle twice at least thickness of spring material

摘要

The coiled valve spring has axially successive coils twisted towards each other (d) or in the opposite direction. The coils have at least three corners (6,7,8). The size of the twist angle (d) is double the thickness of the sprung material. The sprung material is coiled over a rectangular core with rounded narrow sides.