| 摘要 |
PURPOSE: To detect breakage in the early stage and to shorten response time by combining a detection means with a displacing means and arranging them to monitor and displace only the edge of a web. CONSTITUTION: A displacing unit is combined with a sensor above the longitudinal edge of a paper web 1 to constitute a jet flow blow-out nozzle 14 disposed in the proximity of the sensor while directing vertically to the plane of the paper web 1. The nozzle 14 creates an air flow and a thrust generated by the air flow to act on the longitudinal edge of the paper web is regulated not to cause any displacement of the longitudinal edge of the paper web 1 when it is not tensed, i.e., under normal state. Consequently, a thrust shown by an arrow 17 does not cause displacement of web due to tension during normal operation. When the paper web is damaged to decrease web tension, the longitudinal edge of the paper web 1 is displaced as shown by a dashed line by the nozzle 14 to actuate a break detection circuit. |
