US 12,227,901 B2
Method for manufacturing two-sided laminated cardboard, as well as two-sided laminated cardboard manufactured by such a method
Albertus Uil, Wildervank (NL)
Assigned to Eska B.V., Sappemeer (NL)
Appl. No. 17/798,408
Filed by Eska B.V., Sappemeer (NL)
PCT Filed Feb. 10, 2021, PCT No. PCT/NL2021/050087
§ 371(c)(1), (2) Date Aug. 9, 2022,
PCT Pub. No. WO2021/162548, PCT Pub. Date Aug. 19, 2021.
Claims priority of application No. 2024873 (NL), filed on Feb. 10, 2020.
Prior Publication US 2023/0084783 A1, Mar. 16, 2023
Int. Cl. D21H 19/84 (2006.01); D21F 11/12 (2006.01); D21H 23/64 (2006.01)
CPC D21H 19/84 (2013.01) [D21F 11/12 (2013.01); D21H 23/64 (2013.01)] 2 Claims
OG exemplary drawing
 
1. A method for manufacturing two-sided laminated cardboard, wherein on both sides of an intermediate cardboard layer a first outer layer and a second outer layer, respectively, are laminated, and wherein during said laminating:
the intermediate layer is conveyed in a conveying direction through a laminating apparatus;
the first outer layer is glued together with the upper side of the intermediate layer by means of a rotating upper roller under exertion of a first torque, and the second outer layer is glued together with the lower side of the intermediate layer by means of a rotating lower roller under exertion of a second torque;
a measuring roller measures a measured band tension, in the conveying direction, of the intermediate layer being conveyed;
for the purpose of a taut running of the intermediate layer, the intermediate layer being conveyed is kept at a pre-determined constant operational band tension in the conveying direction in dependence of said measured band tension and in dependence of said pre-determined constant operational band tension; and
for the purpose of counteracting concaveness or convexness, in the conveying direction, of the two-sided laminated cardboard to be manufactured, band tensions of the first outer layer and the second outer layer are controlled;
wherein in said controlling of said band tensions of the first outer layer and the second outer layer:
a torque addition sum of the first torque and the second torque is controlled towards a pre-determined constant value of said torque addition sum, said pre-determined constant value being obtained from experience; and
a torque difference between the first torque and the second torque is controlled towards a pre-determined value of said torque difference, said pre-determined value of said torque difference being obtained from experience, while maintaining said controlling of said torque addition sum towards said pre-determined constant value of said torque addition sum.