GB969797A - Improvements in wrapping machines - Google Patents

Abstract

969,797. Feeding webs. J. W. J. GREGORY. May 1, 1962 [Jan. 23, 1962], No. 2395/62. Heading B6B. [Also in Division B8] In a wrapping-machine of the type described in Specifications 453,165, 542,234, 551,523, 566,702, where wrapping web is drawn off a reel in amounts corresponding to the girth of an article being wrapped together with an overlap, a photo-electric monitor is positioned to monitor registration marks spaced on said web at intervals corresponding to the length of a single wrapper, so that, should a larger article take more web and cause a second registration mark to pass beneath said monitor, means is actuated after severing to draw back the free end of said web a fixed amount. In this manner a more consistent positioning of the wrapper pattern on the wrapped article is obtained. Each article passes along conveyers 2, 4 on to a platform 8, thereby catching an end 6a of web therebeneath and drawing it from the reel, and is moved upwards, a roller 10 meanwhile moving to draw the web down to provide an overlap, the roller being initially adjusted to give a greater overlap than normally required, whereafter a blade 11 severs the web. The article is then pushed off the platform by a member 9 and conveyed past further folding and heatsealing means (not detailed). If a second mark passes under the photoelectric monitor 12, indicating that a prearranged length of wrapper has been exceeded, a signal transmitted by the monitor will be stored by cam-operated switch means (Fig. 3, not shown) to cause the web to be clamped by solenoid-operated members 16, and a roller 15 to push it down a fixed amount between rollers 14, thus drawing back the free end 6a, and also reducing the amount of overlap provided at the next wrapping operation. The stroke of roller 15 may be varied. Specification 969,798 also is referred to.