SUPPORT STRUCTURE DEFINING A FLAT SUPPORT SURFACE

A support structure defining a flat support surface (18) for supporting a web material, the support structure comprising a number of beams (10) each of which has a cross-section elongated in a first direction (z) normal to the support surface (18), the beam (10) having a ruler edge (16) extending in a second direction (x) in parallel with the support surface (18), the support surface being defined by the ruler edges (16) of the beams, the support structure further comprising a number of adjustment mechanisms (20) for adjusting the positions of the ruler edges (16) in the first direction (z), wherein each beam (10) has a base part (12) and a ruler part (14), the ruler part (14) defining the ruler edge (16) and being connected to the base part (12) by at least three adjustment mechanisms (20) distributed over the length of the beam, and each adjustment mechanism (20) comprises a lever (22) that is pivotable relative to the base part (12) about a fixed fulcrum (24), is connected to the ruler part (14) by an articulated link (26), and has an adjustment arm (28) with a free end (30) that is adjustable in its position in the first direction (z) relative to the base part (12).