| 摘要 |
PROBLEM TO BE SOLVED: To provide a coupling capable of easily and precisely positioning a die when correcting (sizing) it. SOLUTION: The coupling is made of a sintered metal member in which axially extending spline grooves 3 are formed at every circumferentially equivalent distance on the inside peripheral face. A plurality of axial positioning grooves 5 are formed at every same pitch. A positioning groove 5 of the outside peripheral face of the coupling 1 is set to coinside with a protrusion on the inside peripheral face of the sizing hole of the die to relatively position the coupling 1 against the die. As the positioning groove on the outside peripheral face of the coupling 1 and the spline groove 3 on the inside peripheral face have mutually relative relation, by relatively positioning the coupling to the die through the positioning groove on the outside peripheral face, the spline axis is relatively positioned to the die and further, it is relatively positioned to the core rod having a relative positional relation to the die. |
