| 摘要 |
PURPOSE:To manufacture a multiple V-groove pulley having a dimensionally accurate V-groove part by slotting the outer peripheral side-face of a discoidal blank material into a V-shaped cross section by a slotting roll while forming the V-shaped cross section into a stepped shape toward the deepest part. CONSTITUTION:By a slotting roll 4, having a multistep chevron-shaped forming face 4a for forming the outer peripheral side-face of a discoidal blank material Q; a V-shaped slot groove S11, having a stepped cross section toward the deepest part, is formed in the outer peripheral side-face of material Q while compressing the material Q in its diametral direction and increasing its thickness. This slot groove S11 contains plane parts F parallel to the center line of material Q, and each plane part F is made to correspond to each crest part (m1) of a preforming roll 22, and also the quantity of blank material Q partitioned by the center line of each plane part F is set so as to make it equal to the quantity of each interroot blank material of a final product. Next, after expanding said slot groove S11 into a trapezoidal cross-sectional shape and forming it into a V- groove part S22 of wave-shaped face W, a multiple V-groove part S33 is formed by a forming roll 33 to obtain a multiple V-groove pulley. |
