Belt for continuously variable transmission

摘要

A belt (15) for a continuously variable transmission is formed by supporting a large number of metal elements (32) on a metal ring assembly (31,31) wherein multiple sheets of endless metal rings are layered. The durability of the entire metal ring assembly (31) is enhanced by increasing the wear life of the radially inner surface of the metal ring of the innermost layer (331) which is the layer which is most easily fractured. The thickness of the metal ring (331) of the innermost layer is different from the thickness of the metal rings of layers other than the innermost layer. The thickness of the metal ring of the innermost layer is set so that the stress amplitude applied to the radially outer surface of the metal ring of the innermost layer is not more than the stress amplitude applied to the radially outer surfaces of the metal rings of layers other than the innermost layer. By setting the thickness of the metal ring of the innermost layer at 0.042 mm to 0.161 mm when the thickness of the metal rings of layers other than the innermost layer is 0.185 mm, the stress amplitude sigma a1 applied to the metal ring of the innermost layer becomes lower than the stress amplitude sigma an of 25.65 kgf / mm<2> applied to the other metal rings. Thus the durability of the metal ring of the innermost layer can be enhanced to increase the life span of the entire metal ring assembly.