Patent ID: 6012318
Filing Date: 2000-01-11
Classification: B21D,B21H,Y10T

Abstract:
A method of producing a sheet metal pulley for a V belt from a sheet metal cylindrical member having a circular base plate portion and a cylindrical portion at an outer periphery of the circular base plate portion, the cylindrical portion extending in elongation on one side of the base plate portion, and defining a root portion, the method comprising the steps of: opening an annular first valley portion in a V-like shape by slitting the root portion of the cylindrical portion and the outer periphery of the base plate portion continuous to the root portion; preparing the cylindrical portion for a second valley portion to be continuous to the first valley portion, thereby together forming an intermediate shaped member which has the first valley portion in the outer periphery of the base plate portion and in which the cylindrical portion for forming the second valley portion is continuous to the first valley portion; and applying a pressing force in an axial direction to the cylindrical portion of the intermediate shaped member while rotating the intermediate shaped portion, and thereafter pressing an intermediate portion of the intermediate shaped member in the radial direction of the cylindrical portion to be inwardly bent, thereby shaping the pressed portion into the second valley portion.