In the continuous, mass production of paper, a continuous web of paper is formed, pressed and dried and then wound into finished logs at the reel. The web advances continuously at a high rate of speed through the production line and into the horizontal winding reel where it is wound upon spools into discrete logs for later processing.
When starting a new roll on an empty core or spool, the paper web is easily adhered to the metal surface of the new roll by wetting the surface. In this manner the end of the web is easily adhered to the roll, wound around to make the first winding layer, after which the web is pulled against itself and held securely as further windings accumulate.
Occasionally, however, a problem or defect occurs upstream in the production line which causes the web to break when a core is only partially completed. In conventional paper production this results in a time consuming and costly procedure to thread the web through the machine and secure it to the partial reel.
In particular, after the upstream problem or defect is corrected, a new tail is formed which must be threaded into the reel and around the spool or core. A tail is a narrow strip having a width which is controlled by a squirt on the forming fabric. After the tail is properly threaded onto the partial reel, the tail is progressively widened until it reaches the full width of the web.
In a conventional reel, the reel drum pivots against the spool or core. The tail and eventually the full width web passes down through the nip between the drum and the spool, underneath and around and then over the top of the spool and back through the nip. The principal problem in threading the reel is to convey the tail down around the bottom and up over the top of the spool because gravity tends to pull the tail away from that portion of the spool.
In the conventional papermaking production line, a worker must physically go down beneath the spool with an air hose and blow the tail around, underneath and over toward the top of the partially filled spool. This procedure is both a danger to the worker and results in considerable down time for the production line. Typically this down time is in the range of 15 minutes to an hour.
It is therefore an object of the present invention to increase the safety of the paper making operation and at the same time reduce the production line down time.
A great variety of systems have been used for guiding or threading a web through paper manufacturing machinery. These include the rope systems in which rope belts are used for guidance, vacuum-belt systems in which a vacuum draws the web against a porous belt which delivers the tail or web to the desired position and air tube threaders in which an air blast from fixed pipes blows a tail or web against a roll. Other systems use air foils or the Coanda effect to entrain air and draw the web against the roll. None of these, however, have been satisfactory for guiding a web, such as a paper tail, beneath and up around to the top of a rotating, partial reel upon which it is to be wound.