Machine for the production of plastic film bags with means of positioning with respect to each other the trailing end of a film being used up and the leading end of a reserve film

摘要

A machine for the production of weldable plastic film bags from a strip reel, and for the filling of the said bags, comprises means of supporting and unwinding a first strip reel (B₁); means of supporting a second reserve strip reel (B₂); and means (41, 49) of cutting and welding the strip (N), to automatically make the join between the trailing end of the strip being unwound from the first reel (B₁) and the leading end of the strip on the second reel (B₂) when the first reel is about to be used up. In order to bring the strip on reel (B₁) into phase with the strip on reel (B₂), there are provided means (5, 7, 9) of delimiting a predetermined length of the path of the strip between the means of forming, filling and sealing the bags and the means (41, 49) of cutting and welding the strip; a first reference (151) down-line from the means of welding and cutting the strip; and a second reference (153) for the strip from the second reel.