| 摘要 |
PURPOSE:To decrease considerably the cost of manufacture by forming a pulley part of a sheet metal, putting the pulley part into a forming die and connecting and forming a boss part by a die cast molding method to the coupling part formed preliminarily to the pulley part. CONSTITUTION:A pulley part 1 is formed of a sheet metal and holes 3 for coupling are punched to the disc center part 2 thereof along the circumference. Such pulley part 1 is put into a forming die A for die casting and a molten metal is poursd into the die to mold integrally a boss part 4. The molten metal solidifies in the state of entering the holes 3 thereby coupling the pulley part 1 and the boss part 4. |
