| 摘要 |
PURPOSE:To make easy mass production of a lightweight and inexpensive plateworked pulley by building up an annular thick walled part in the outside circumferential region of a circular plate and forming an annular corner part for the bottom of a cup-shaped pulley blank material in the thick walled part then subjecting the same to pressing for forming a tooth profile. CONSTITUTION:A circular plate a1 is pressed and a plate b1 built up beforehand with a thick walled part 8 in the outside circumferential region with the part 4b corresponding to a bottom plate 4 decreased in wall thickness is prepd. The plate b1 is then subjected to pressing for deep drawing to form a cup-shaped pulley blank material 1b consisting of a cylindrical part 3b and a bottom part 4d and to form an annular corner part 5b for the bottom of the material 1b with the thick walled part 8, thereby building up excess metals 6b, 6c by the part 8 in the part 5b. The excess metals 6b, 6c are elongated in parallel with the axial direction, i.e., the cylindrical part 3b by pressing for forming a tooth profile whereby a tooth profile 2 is formed. |
