Laminating apparatus utilizing offset rollers

Claim 2

PLASTIC FILM LAMINATING APPARATUS HAVING A SINGLE PAIR OF PRESSURE ROLLS EACH MOUNTED FOR ROTATION ON ITS OWN AXIS AND COMPRISING: MEANS RESILIENTLY BIASING SAID ROLLS INTO PRESSURE ENGAGEMENT WITH EACH OTHER, A HEATING STATION COMPRISING FRIST AND SECOND HEAT CONDUCTIVE MEANS POSITIONED SO AS TO GUIDE A MULTI-SHEET WORKPIECE TO BE LAMINATED INTO THE NIP FORMED BY SAID ROLLS, SAID FIRST AND SECOND MEANS BEING DISPOSED ONE ABOVE THE OTHER AND HAVING FLAT CONFROMING SURFACES THAT ARE IN ENGAGEMENT WITH EACH OTHER, MEANS MOUNTING SAID FIRST AND SECOND MEANS FOR RELATIVE SEPARATING MOVEMENT OF SAID CONFRONTING SURFACES SO THAT A WORKPIECE TO BE LAMINATED MAY BE INSERTED BETWEEN THEM AND POSITIONED IN THE NIP OF SAID ROLS. SAID MOUNTING MEANS INCLUDING GUIDE MEANS FOR PREVENTING HORIZONTAL MOVEMENT OF SAID FIRST AND SECOND MEANS, MEANS FOR HEATING SAID FIRST AND SECOND MEANS, AND DRIVE MEANS FOR ROTATING AT LEAST ONE OF SAID ROLLS TO DRAW SAID WORKPIECE FROM SAID HEATING STATION THROUGH SAID ROLLS SO THAT THE SHEETS OF SAID

Claim 3

Apparatus according to claim 1 wherein said axes and said surfaces are substantially horizontal.

Claim 4

Apparatus according to claim 2 wherein the axes of said rolls lie in a common plane that extends at an angle of between about 5* and about 12* to a plane that is parallel to said axes and normal to said confronting surfaces.

Claim 5

Apparatus according to claim 1 wherein said first means is mounted above said second means and said second means is fixed while said first means is moveable vertically relative to said second means.

Claim 6

Apparatus according to claim 4 wherein the confronting surface of said second means lies in a plane that is substantially tangent to one of said rolls.

Claim 7

Apparatus according to claim 4 wherein said first means includes an electrical heating element.

Claim 8

Plastic film laminating apparatus comprising a pair of pressure rolls, a pair of spaced arms rotatably supporting one of said rolls for rotation on its own axis, means rotatably supporting the other of said rolls for rotation on its own axis, said rolls being parallel to one another, a pair of side plates, means moveably mounting said arms to said side plates so that said one roll can move into and out of engagement with said other roll, means resiliently biasing said one roll into pressure engagement with said other roll, a heating station comprising first and second heat conductive metal plates positioned so as to guide a multi-sheet workpiece to be laminated into the nip formed by said rolls, said first and second plates having confronting surfaces that normally engage one another, means mounting said first and second plates for relative separating movement of said confronting surfaces so that a workpiece to be laminated may be inserted between them and positioned in the nip of said rolls, means for heating at least one of said first and second plates, and drive means for rotating at least one of said rolls in a direction to draw said workpiece from said heating station through said rolls so that the sheets of said workpiece are forced together by said rolls, said confronting surfaces having end portions located close to the nip of said rolls that are located in planes that are parallel to the axes of rotation of said rolls, said rolls being offset so that their axes lie in a common plane that extends at an acute angle to the plane of said end portions, whereby to minimize curling of said workpiece as it passes out from between said rolls.

Claim 9

Plastic film laminating apparatus comprising a pair of pressure rolls, a pair of spaced arms rotatably supporting one of said rolls for rotation on its own axis, means rotatably supporting the other of said rolls for rotation on its own axis, said rolls being parallel to one another, a pair of side plates, means moveably mounting said arms to said side plates so that said one roll can move into and out of engagement with said other roll, means resiliently biasing said one roll into pressure engagement with said other roll, a heating station comprising first and second heat conductive metal plates positioned so as to guide a multi-sheet workpiece to be laminated into the nip formed by said rolls, said first and second plates having confronting surfaces that normally engage one another, means mounting said first and second plates for relative separating movement of said confronting surfaces so that a workpiece to be laminated may be inserted between them and positioned in the nip of said rolls, means for heating at least one of said first and second plates, and drive means for rotating at least one of said rolls in a direction to draw said workpiece from said heating station through said rolls so that the sheets of said workpiece are forced together by said rolls, said confronting surfaces having end portions located close to the nip of said rolls that are located in planes that are parallel to the axes of rotation of said rolls, said rolls being offset so that their axes lie in a common plane that extends at an acute angle to the plane of said end portions, whereby to minimize curling of said workpiece as it passes out from between said rolls.

Claim 10

Apparatus according to claim 7 wherein said heating means comprises an electrical resistance heating element that is mounted to one of said first and second plates.

Claim 11

Apparatus according to claim 8 comprising first and second thermostat switches mounted to said first and second plates respectively, said first and second thermostat switches being adapted to operate at a first lower temperature and a second higher temperature respectively, an indicator light, means connecting said indicator light to said first thermostat switch so that said light is energized when said first thermostat switch is operated, and means connecting said second thermostat switch to said heating element so that said heating element is energized so long as said second thermostat switch is below said second higher temperature.

Claim 12

Apparatus according to claim 9 wherein said other roll is rotatably supported by said side plates.

Claim 13

Apparatus according to claim 10 wherein said resilient biasing means comprise leaf springs pivotally mounted to said side plates and engaging axial extensions of said one roll, and means urging said leaf springs against said axial extensions.

Claim 14

Apparatus according to claim 9 wherein said side plates are located at opposite ends of said second plate, and further comprising means affixing the ends of said second plate to said side plates, said first plate being located above said second plate, said means mounting said first and second plates comprising guide means affixed to said side plates for preventing endwise and lateral movement of said first plate while simultaneously permitting vertical movement thereof.