Roller driving system for feeding sheet materials

Claim 1

In a roller driving system for feeding sheet materials comprising: a plurality of roller pair units in series, each roller pair unit comprising rollers on opposite sides of said sheet material, rotating in opposite directions with reference to each other and frictionally driving said sheet material by nipping said sheet material between the two rollers of said roller pair units to pass said sheet material from roller pair unit to roller pair unit, the improvement comprising: each of said roller pair units being driven from one side only with each roller of said roller pair units carrying a gear to the same side thereof and in mesh with one another with one roller of a given roller pair unit driven by the other, the axes of said rollers for each roller pair unit defining a plane which is at right angles to the plane of sheet material moving between the rollers of the roller pair units, drive shafts extending along the direction in which the sheet materials are fed on each side of the roller pair units, gears carried by said drive shafts at locations corresponding to given roller pair units and in mesh with a gear carried by one of said rollers for each roller pair unit, the improvement wherein: each of said roller pair units is driven from one side only, and said roller pair units are driven alternately from opposite sides by way of said drive shafts and the gears carried thereby such that the nipping pressure applied to said sheet material as it progresses through said system from roller pair unit to roller pair unit is balanced.