METHOD FOR MANUFACTURING SCREW, WHIRLING CUTTER, AND SCREW MANUFACTURING DEVICE

摘要

Provided is a method for manufacturing a screw which is capable of solving a problem due to rolling or cutting and prevents the movement path of an insert (13) from interfering with a desired curve line of the screw at the time of exiting and entering the curve line, thereby providing an intended curve line to the screw by a thread whirling process. In the method for manufacturing the screw, in the case where a lead angle and an attachment angle (ß) of the screw are different from each other, the attachment angle is determined from the following equation. Attachment angle = tan-1{n*pitch/(p*D1)} D1 = {(screw core diameter + screw outside diameter)/2} + ?T screw core diameter = D1 = screw outside diameter In the case where ?T > 0 is satisfied, {(screw outside diameter - screw core diameter)/2}*0.2 < ?T < {(screw outside diameter - screw core diameter)/2} In the case where ?T < 0 is satisfied, -{(screw outside diameter - screw core diameter)/2} < ?T < -{(screw outside diameter - screw core diameter)/2}*0.2 where D1?0, ?T?0, and n is the number of threads