| 摘要 |
PROBLEM TO BE SOLVED: To determine any chipping of a fillet roller with good accuracy with simple control.SOLUTION: The maximum pressure change &Dgr;Pmaxj and the integrated pressure change value &Dgr;Pj are calculated by using the sequentially calculated pressure change &Dgr;Pi per predetermined time (Steps S102-S114), the permissible ranges &Dgr;Pjmav±3&sgr;sj and &Dgr;Pmaxjmav±3&sgr;mj are set by using nearest 20 sets of integrated pressure change value &Dgr;Pj-19 to &Dgr;Pj and the maximum pressure change value &Dgr;Pmaxj-19 to &Dgr;Pmaxj including the maximum pressure change &Dgr;Pmaxj and the integrated pressure change &Dgr;Pj (Steps S114-S118), and it is determined whether or not any chipping is caused in a fillet roller R depending on whether or not the maximum pressure change value &Dgr;Pmaxj and the integrated pressure change value &Dgr;Pj are within the range of the permissible value range &Dgr;Pmaxjmav±3&sgr;mj and &Dgr;Pjmav±3&sgr;sj, respectively (Step S120). |
