| 摘要 |
PROBLEM TO BE SOLVED: To stop a ring rail at a position causing less thread breakage when the ring rail is reactivated regardless of the ring rail position in emergency shutdown due to power failure and manual emergency stop and others.SOLUTION: A spindle deceleration gradient after an emergency stop signal is emitted is obtained. A spindle rotation speed when a ring rail reaches a position, at which the deceleration gradient descends by a target movement amount from a start of descending, is calculated based on the obtained spindle deceleration gradient. If the spindle rotation speed reaches the calculated spindle rotation speed when the ring rail is moving up, the ring rail is lowered by reversely rotating the ring rail until the spindle stops. If the spindle rotation speed reaches the calculated spindle rotation speed when the ring rail is moving down, the ring rail is continuously lowered until the spindle stops.SELECTED DRAWING: Figure 2 |
