Patent ID: 8979012
Filing Date: 2015-03-17
Classification: B65H

Abstract:
1. A method for separating a web material in a winding machine, which comprises an upper winding roller, at least one guide plate, a lower winding roller, and a rider roller, wherein the guide plate is arranged at a location close to and below the upper winding roller and forms a channel with the upper winding roller, the upper winding roller, the lower winding roller, and the rider roller forming therebetween a winding nip, a separation mechanism being arranged below the upper winding roller and comprising a pivot shaft and a pinch arm extending from the pivot shaft, the pinch arm having a web engagement end, the method comprising the following operations: (a) having a web material borne on a lower circumferential surface of the upper winding roller that is rotatable in a predetermined rotation direction to have the web material fed into and passed through the channel; (b) winding the web material which passes through the channel around a first core in the winding nip to form a paper roll; (c) rotating the pinch arm to have the web engagement end periodically reaching an engagement position where the web engagement end opposes the upper winding roller, the web engagement end of the pinch arm being engageable with the web material while maintaining a predetermined spacing from the upper winding roller when at the engagement position, such that the pinch arm does not contact the upper winding roller, the pinch arm being rotatable in a direction opposite to the predetermined rotation direction of the upper winding roller; (d) providing a vacuum suction force at the web engagement end of the pinch arm; (e) feeding a second core into the channel; (f) reducing rotational speed of the lower winding roller relative to the upper winding roller to have the web material slightly slackened within the channel to form a slack portion; (g) guiding the slack portion of the web material with the web engagement end of the pinch arm, by use of the vacuum suction force, to have at least a portion of the slack portion of the web material clamped between the second core and the guide plate; and (h) subjecting the web material to a pulling force induced by the paper roll that is formed in the winding nip so as to tear and thus separate the web material at a location that is between the location where the web material is clamped between the second core and the guide plate and the paper roll of the first core.