Roll-unwinding device for automatically changing rolls at full running speed

Claim 1

A roll-unwinding device for automatically changing rolls or a web-type material for the continuous delivery of the web-type material as it is unwound from successive rolls to a treatment station, comprising a support frame which comprises a pair of laterally spaced support elements, a first pair of laterally spaced longitudinally extending roll support arms positioned between said support elements and arranged to support a roll of web-type material between said support arms as the material is unwound, a second pair of laterally spaced longitudinally extending roll support arms positioned between said support elements and arranged to support another roll of web-type material between said support arms as it is unwound, the support arms of said first pair being spaced laterally from the support arms of said second pair, means mounted on said support elements for pivotally supporting said first pair and second pair of roll support arms, the support arms of said first and second pairs each having a pivot axis and a roll support axis with the pivot axis of each spaced in the longitudinal direction from its roll support axis, the support arms of said first pair having a length between their pivot axis and roll support axis which is different from the length of the support arms of said second pair between their pivot axis and roll support axis, means mounted on said support frame for pivoting said first and second pairs of roll support arms through limited angular distances between a plurality of roll positions, and means cooperating with said first and second pairs of support arms for connecting the webs of materials from a succeeding roll to a preceding roll and for cutting the web material on the preceding roll after the connection has been made.