| 摘要 |
<p>Metal parts having two or more yokes used, for example, for a universal joint for an automobile, are manufactured by pressing a solid metal rod material from one end in a closed cavity formed by two opposing dies, urging another end of the rod to an impression formed in one of the two dies to divide the rod material into two or more bodies and extruding the divided rod material into hollow portions parallel to the pressing direction. The shaping apparatus comprises two opposing dies forming a closed cavity and a punch pressing the metal solid rod material in the closed cavity from one end. One of the two dies is provided with a guide hole for guiding the rod material, the hole perforating said die in a direction perpendicular to the contact surfaces of both dies. The other die is provided with a projected portion located opposite the above described guide hole, which portion is urged against the top end portion of the rod material and divides said rod material into two or more bodies. An impression is formed in the inside of the projected portion and a plurality of passageways guide the divided rod material in a direction parallel to the guide hole. The punch slides in the guide hole formed in said one die and extrudes one end of the rod material. The apparatus may be provided with a counter punch which is inserted into the passageways provided in said other die and applies back pressure to each top end surface of the divided material extruded into the passageways.</p> |
