Tenter unit

A width stretching unit for a web of material, the width stretching unit comprising:

• a first needle disc unit having first and second needle discs disposed along a first axis at an axial distance corresponding to a width of the web of material, the first and second needle discs having a multiplicity of peripherally distributed needles pointing radially outward, the multiplicity of needles intended for insertion into selvedges of the web of material;
• a pivoting mechanism for pivoting a first rotational axis and a second rotational axis of the first and second needle discs, respectively;
• a pinning mechanism for pinning the web of material by its edges onto the multiplicity of needles of the first and second needle discs in a region of reduced axial distance between edges of the first and second needle discs;
• a second needle disc unit associated with the first needle disc unit, the second needle disc unit having a second axis parallel to the first axis, the second needle disc unit further having third and fourth needle discs rotatably mounted substantially perpendicular to the second axis, the third and fourth needle discs rotating about the second axis at the same peripheral speed as the first and second needle discs, an axial distance between the third and fourth needle discs being equal to the axial distance between the first and second needle discs in a zone of increased distance between the first and second needle discs;
• wherein the edge of the first needle disc practically touches the edge of the third needle disc in the zone of increased distance, and the edge of the second needle disc practically touches the edge of the fourth needle disc in the zone of increased distance so that it is possible for the web of material to be transferred from the first and second needle discs to the third and fourth needle discs, respectively, without relinquishing the pinning on at least one of the first or third needle discs and at least one of the second or fourth needle discs.