Multiply paperboard machine

Claim 1

A multiply paperboard manufacturing machine comprising: A. a top fibrous ply holding and wet pressing unit having: four horizontally positioned spaced-apart rolls equally spaced from a vertical plane normal to the axes of the rolls, with said rolls being a tail roll, head roll, foot roll and guide roll, parallel to each other, a fibrous ply forming endless fabric belt wound over the four rolls, the run of fabric belt between the head roll and the tail roll being inclined, a vacuum box beneath a run of the fabric belt extending from the tail roll to the head roll, and a high vacuum box behind a run of the fabric belt extending from the head roll to the foot roll; B. a plurality of fibrous ply forming apparatus, with each such apparatus comprising: four horizontally positioned spaced-apart rolls equally spaced from a vertical plane normal to the axes of the rolls, with said rolls being a tail roll, head roll, foot roll and guide roll, parallel to each other, a fibrous ply forming endless fabric belt wound over the four rolls, the run of fabric between the head roll and the tail roll being inclined, a low-vacuum box beneath a run of the fabric belt extending from the tail roll to the head roll for dewatering a forming fibrous ply deposited on said fabric run, a high-vacuum box behind a front face run of the fabric belt extending vertically from the head roll to the foot roll, said run constituting an apparatus front face, and a headbox positioned to deposit a fibrous ply on the fabric belt run between the tail roll and the head roll; the plurality of fibrous ply forming apparatus being positioned in a substantially vertical arrangement with the front face of every other apparatus fronting on, and being on, the same side of a vertical line; the vertically an uppermost forming apparatus for a first fibrous ply being positioned to have its head roll opposite and close to the vacuum box of the holding unit behind the run of the fabric belt extending from the head roll to the foot roll of the holding unit; the head roll of the second and subsequent ply forming apparatus being positioned opposite and close to the lower portion of the high-vacuum box of the next higher fibrous ply forming apparatus; the foot roll of each fibrous ply forming apparatus, except the lowermost apparatus, being positioned opposite and close to the upper portion of the high-vacuum box of the next lower fibrous ply forming apparatus; and C. a bottom pressure roll opposite and close to the lower portion of the high-vacuum box of the lowermost fibrous ply forming apparatus.