Apparatus for producing a continuous succession of wrapper sheets for use in a wrapping machine

Apparatus for making wrapper sheets for use in a wrapping machine, comprising;

• feeder means for alternately delivering a first web of sheet material from a first source of such material and a second web of such material from a second source thereof via a first path and a second path respectively to an inlet end of a principal path whereto the first and second paths converge, to deliver successive wrapper sheets via the principal path, the feeder means including first and second feeders located adjacent the first and second paths respectively and each disposed to feed a leading portion of the respective web, incident to the delivering of the other web, from the respective source along the respective path and to stop the leading portion in a starting position thereof with a leading edge at a point of the respective path adjacent the inlet end of the principal path;
• cutter means comprising a principal cutter located adjacent the principal path for producing the successive wrapper sheets from either web of sheet material, and first and second auxiliary cutters located respectively adjacent the first and second paths, each for cutting a final portion of sheet material from the respective web when the respective web is nearly exhausted;
• and
• control means for controlling the feeder means and cutter means to maintain a continuous and uniform stream of the wrapper sheets travelling over the principal path in succession to one another and free of mutual overlapping during a transition to the delivering of the other web as well as during the delivering of either web from the respective source, comprising, (a) a primary control controlled by the principal cutter to time the feeder means in synchronism with the principal cutter, (b) first and second transition controls associated with the first and second auxiliary cutters respectively and each including a sensor adjacent the respective path, between the respective source of sheet material and the respective auxiliary cutter, for sensing that the source is nearly exhausted, and for thereupon activating said respective auxiliary cutter to then detach a final wrapping sheet at a trailing edge thereof, from a final portion of the nearly exhausted web which travels over the respective path, while activating the feeder means to begin delivering the other web with its leading edge following said trailing edge into the principal path, and (c) memory and shift register means for enabling the feeder means to time the feeding of the webs so as to maintain the continuous and uniform stream of wrapper sheets while enabling the principal cutter to operate at variable speeds and thereby to cut the travelling web into successive sheets of variable length.