Folding roller comprising coating

A folding apparatus for forming a fold at a signature to be folded, wherein the signature to be folded is pressed by means of a folding blade into an incoming nip of a counter-rotating folding roller pair, wherein at least one folding roller of the folding roller pair is a folding roller comprising a jacket surface at least partially having an elastic coating that is compressible, wherein each folding roller of the folding roller pair defines an axis of rotation and a first folding roller of the folding roller pair defines a first roller radius and a second folding roller of the folding roller pair defines a second roller radius, and wherein an axial distance between the axis of rotation of the first folding roller and the axis of rotation of the second folding roller is equal to or greater than the sum of the first roller radius and the second roller radius when the coating is not compressed and is less than the sum of the first roller radius and the second roller radius when the coating is compressed.

A folding apparatus for forming a fold at a signature to be folded, wherein the signature to be folded is pressed by means of a folding blade into an incoming nip of a counter-rotating folding roller pair, wherein at least one folding roller of the folding roller pair is a cylindrical folding roller comprising a plurality of segments disposed in a circumferential direction, and wherein at least one folding roller of the folding roller pair comprises a jacket surface that at least partially having an elastic coating that is compressible.

A method for operating a folding apparatus, wherein to form a fold at a signature to be folded, the signature is pressed by means of a folding blade into an incoming nip of a counter-rotating folding roller pair having axes of rotation and spaced apart at an axial distance between the axes of rotation, comprising providing two folding rollers having roller radii, wherein at least one of the folding rollers of the folding roller pair comprises a jacket surface at least partially having an elastic coating that is compressible, and placing the two folding rollers of the folding roller pair such that the axial distance between the axes of rotation is equal to or greater than the sum of the roller radii when the coating is not compressed and is less than the sum of the roller radii when the coating is compressed.