| 摘要 |
A thread rolling method for a gear using cylindrical capable of achieving a proper tooth profile by the use of cylindrical dies in which no slippage occur during the processing is provided. The method includes the steps of placing a work having a cylindrical outer surface to be supported to a support to be freely rotatable about a rotation axis of the cylindrical outer surface, placing a pair of the cylindrical dies each rotatable about an axis parallel to the rotation axis to face each other across the work, thrusting the pair of cylindrical dies against the work, the cylindrical dies being synchronized with each other in rotating speed and thrusting amount via a drive mechanism, and determining an outer diameter of the work, when rotary movement of the cylindrical dies and the work rotated together is shifted from friction gear movement based on thrusting forces exerted from both the cylindrical dies and the work to gear movement based on the engagement between the work and the cylindrical dies at tooth grooves formed in the work by thrusting the cylindrical dies against the work, in which a dimension obtained by dividing an outer circumferential dimension of a dedendum circle of the tooth grooves by the number of teeth to be formed is equal to an addendum circular pitch of each of the cylindrical dies. |
