Assembly for processing blanks

An assembly for processing blanks, and which comprises a first endless conveyor (1) with location for holders (3) for the blanks, and which further comprises at least one stationary processing station (7) for carrying out said processing, said first conveyor comprising a number of self-propelled vehicles (2), where each vehicle is equipped with a tool (4), and a holding device for the blank holder (3), wherein the first conveyor (1) comprises at least one guiding line (19) comprising a row of colored spots marked on a running surface (18), wherein each vehicle (2) is provided with sensors (20) for detecting said guiding line as well as guiding means (22) which are adapted to guide said vehicle towards or adjacent the guiding line (19) of the running surface, the running surface (18) comprises a main path (1a) and at least one siding path (10, 11), which siding path can be used either for a temporary removal/replacement of the tool (4) on each vehicle (2) or for allowing an overtaking or temporary moving aside of each vehicle (2) relative to the main path without involving a change of the succession of vehicles on the main path, the processing station (7) is positioned outside both the siding path and the main path, the guiding line of each siding path (10) over the majority of its length extends substantially parallel to the opposing length (1′) of the guiding line of the main path (1a), and the guiding line (10) of said siding path is without a direct connection with the guiding line (1a) of the main path at the branching location (45, 46), but instead extends relatively close and parallel to the guiding line of said main path at said locations (45, 46).