Unit for the guidance of sheets of flexible material for the purpose of forming a three-dimensional assembly

Apparatus for the guidance of sheets of flexible material for the purpose of forming a three-dimensional assembly, said apparatus including a drive device formed from at least one bearing plate, a drive wheel constructed and arranged to press flexible sheet material to be guided onto said bearing plate, means for control of said drive wheel, and a position detector for detecting the position of an edge of sheet material on said bearing plate, said detector including at least one photoelectric detector placed in front of said edge used in the guidance of said sheet material and electronic circuits converting the signals provided by said detector into a control signal for said drive device, wherein the drive device includes a spherical drive wheel which moves freely around a spindle, said spindle being parallel to a bearing plate and said spindle being attached at one end to an axially movable shaft by an extension, said extension being approximately orthogonal to said bearing plate and said shaft, said shaft having a means of rotational control provided at the end of said shaft opposite the end attached to said spindle by said extension;

• and a drive roller having an axis which is parallel to said bearing plate and which controls the rotation of said spherical drive wheel, wherein said shaft and said drive roller are supported by common frame means which provide the appropriate angular positions of said shaft and said drive roller.