Apparatus for making corrugated paper board

Claim 1

In a machine for making corrugated paper board of the type having at least one fluted core and at least two spaced facing sheets, from at least two webs of material, each of said webs comprising a respective one of said facing sheets: means defining a feed path in said machine; means for feeding said webs along said feed path; means for bonding said two webs together to form said board, said bonding means comprising heating means; said heating means being at a first location along said feed path; moisturizing means for adding moisture to the drier one of said two facing sheets to equalize the moisture content of said two facing sheets to prevent warping of said board; said moisturizing means being at a second location along said feed path downstream of said heating means and comprising: a plurality of compartments at several locations along the width of the sheet; a plurality of spraying devices, there being a separate spraying device disposed in a separate one of said compartments to thereby spray water onto said one facing sheet at said several locations along the width of the sheet.