Apparatus for making a shingle

Apparatus for cutting a multi-layer shingle comprised of an anterior layer and a posterior layer, to have a natural, random appearance comprising:

• conveyor means for delivering an anterior sheet of shingle material along a predetermined longitudinal path, past a first cutting roll;
• a first cutting roll for cutting the shingle material longitudinally as the sheet of shingle material is delivered therepast;
• said first cutting roll having cutting means thereon for cutting the anterior shingle material into an upper headlap area and a lower tab area, with the tab area comprising a plurality x of tabs separated by longitudinally spaced apart slotted openings;
• means providing a posterior shingle layer;
• severing means for severing both anterior and posterior layers of the shingle transversely to predetermined spaced apart lengths L, measured longitudinally;
• and wherein said first cutting roll has a predetermined cutting design thereon for the tab area of the shingle with the circumference C of said first cutting roll being defined by the formula:
• ##EQU5## and where x the number of full tabs in the anterior shingle layer to be cut and wherein any two partial tabs at ends of the anterior shingle layer to be cut count together as a full tab;
• and
• where n=a whole number no smaller than -50, no greater than 50 and not equal to zero,
• whereby the tab area cut design repeatability for the anterior shingle layer in the longitudinal direction, of shingles made on the apparatus, is different than the length of the shingle in the longitudinal direction, enabling a seemingly random appearance to shingles when laid-up on a roof.