| 摘要 |
PURPOSE:To reduce manufacturing cost by diverting a used opening-closing cylinder, and to rapidly and easily change a gap, by operating valves basing on the results detected by a detector which detects the position of a wrapper roll. CONSTITUTION:A wrapper roll arm 4, being in a open state at the starting of wrapping, is put in rapid closing action until it reaches the prescribed objective position by changing the valve position of a large capacity changeover valve 9 from the neutral position NP to a closing-action position CP. A wrapper-roll position detector 7 detects a moving quantity of a cylinder rod 6 to send the detected signal to a controlling device in order to compute a gap; when the gap reaches the sum of the sheet thickness and an adjusting allowance, the valve 9 is returned to the neutral position and a changeover valve 10 is put to the closing-action position together to reduce oil quantity, flowing into an opening- closing cylinder 5. The wrapper roll arm is stopped and is kept in position by returning the valve 10 to the neutral position at the time when the gap, obtained by the detector 7, coincides a set value of the sheet thickness. |
