Double sided laminating machine

Claim 3

A method as defined in claim 1, in which said laminating rollers have exposed surfaces consisting of a synthetic resin polymer having areas of chromium interspersed therein.

Claim 4

A method as defined in claim 2, in which said sheets of film are contacted with freely-rotating directing rollers between said supply sources and said preheat rollers to produce said sinusoidal path.

Claim 5

A method as defined in claim 1, wherein the step of heating said preheat rollers includes circulating a heated incompressible fluid through said preheat rollers.

Claim 6

A method as defined in claim 4, wherein the step of heating said laminating rollers includes circulating heated oil along an independent path through said laminating rollers, the source of oil for said laminating rollers originating from a separate source of oil than said preheat rollers so that a different temperature can be obtained.

Claim 7

A method as defined in claim 1, including the further step of contacting said sheets of film with said article therebetween with a pair of compressible driven pull rollers that are adjustable by fluid pressure downstream of said laminating rollers to pull the laminated film with said article therebetween through the laminating rollers, and adjusting the fluid pressure on the pull rollers to vary the effective diameter of the pull rollers and thereby the speed of said pull rollers.

Claim 8

A method as defined in claim 6, including the further step of driving one of said laminating rollers and one of said pull rollers while the other of said laminating rollers and said pull rollers are freely rotated.

Claim 9

A method as defined in claim 7, in which the others of said laminating rollers and said pull rollers are independently adjustable by varying fluid pressure.

Claim 10

A continuous laminating system for double laminating an article comprising a pair of laminating rollers in pressure-engaging contact with each other to form a nip which receives an article to be laminated; a pair of film supply rolls, each supplying a continuous web of laminating film with heat activatable adhesive thereon into said nip; a pair of preheat rollers respectively spaced from the respective supply rolls and the laminating rollers and engaging said webs of laminating film; a pair of reversing rollers respectively between said supply rolls and said preheat rollers producing extended surface contact of approximately 180° between said webs of laminating film and said preheat rollers; said laminating rollers being positioned so as to have extended surface contact of substantially more than 90° with said webs of laminating film; a first pair of pull rollers spaced from said laminating rollers with drive means for pulling said webs of laminating film from said supply rolls across said preheat rollers and through said laminating rollers; first heating means for heating said preheat rollers to a temperature below the activating temperature of said adhesive; and second heating means for heating said laminating rollers to a temperature above said activating temperature of said adhesive to thereby prevent stretching or elongation of the webs of laminating film between the preheat rollers and the laminating rollers.

Claim 11

A continuous laminating system for double laminating an article comprising a pair of laminating rollers in pressure-engaging contact with each other to form a nip which receives an article to be laminated; a pair of film supply rolls, each supplying a continuous web of laminating film with heat activatable adhesive thereon into said nip; a pair of preheat rollers respectively spaced from the respective supply rolls and the laminating rollers and engaging said webs of laminating film; a pair of reversing rollers respectively between said supply rolls and said preheat rollers producing extended surface contact of approximately 180° between said webs of laminating film and said preheat rollers; said laminating rollers being positioned so as to have extended surface contact of substantially more than 90° with said webs of laminating film; a first pair of pull rollers spaced from said laminating rollers with drive means for pulling said webs of laminating film from said supply rolls across said preheat rollers and through said laminating rollers; first heating means for heating said preheat rollers to a temperature below the activating temperature of said adhesive; and second heating means for heating said laminating rollers to a temperature above said activating temperature of said adhesive to thereby prevent stretching or elongation of the webs of laminating film between the preheat rollers and the laminating rollers.

Claim 12

A continuous laminating system as defined in claim 9, and further including a second pair of pull rollers downstream of said first pair of pull rollers with means for varying the speed of said first and second pairs of pull rollers with respect to said laminating rollers.