Apparatus for coating a moving web

Claim 1

APPARATUS FOR PROCESSING A RUNNING LENGTH OF WEB MATERIAL COMPRISING FIRST AND SECOND RESERVOIRS FOR HOLDING QUANTITIES OF LIQUIDS, MEANS COMPRISING IMMERSION AND SQUEEZE ROLLS FOR IMPREGNATING SAID WEB WITH LIQUID MAINTAINED IN SAID FIRST RESERVOIR, MEANS FOR SUPPLYING LIQUID TO SAID SECOND RESERVOIR AT A RATE DEPENDENT UPON THE RATE OF MOVEMENT OF SAID WEB MATERIAL, TRANSFERRING MEANS FOR CONTACTING SAID LIQUID IN SAID SECOND RESERVOIR AND TO TRANSPORT SAID LIQUID BY FILM ADHESION TRANSVERSELY TO SAID WEB MATERIAL IMPREGNATED WITH LIQUID FROM SAID FIRST RESERVOIR, SAID TRANSFERRING MEANS INCLUDING A VARIABLY DRIVEN ROLL HAVING EXTERNAL DIMENSIONS CLOSELY CORRESPONDING TO THE INTERNAL CONFIGURATION OF SAID SECOND RESERVOIR TO PRODUCE A RELATIVELY LARGE CHANGE IN THE LEVEL OF SAID LIQUID MAINTAINED IN SAID SECOND RESERVOIR AS A RESULT OF A SMALL CHANGE IN THE QUANTITY OF SAID LIQUID IN SAID SECOND RESERVOIR, AND MEANS TO MEASURE THE AMOUNT OF LIQUID IN SAID SECOND RESERVOIR AND TO AUTOMATICALLY CONTROL THE RATE OF ROTATION OF SAID VARIABLY DRIVEN ROLL IN RESPONSE TO SMALL VARIATIONS IN THE AMOUNT OF SAID LIQUID IN SAID SECOND RESERVOIR SUCH THAT, WITH SAID SECOND RESERVOIR SUBSTANTIALLY FULL OF LIQUID, SAID LIQUID IS TRANSFERRED FROM SAID RESERVOIR TO SAID WEB MATERIAL BY SAID TRANSFERRING MEANS AT A RATE IN EXCESS OF THAT WHICH SAID LIQUID IS SUPPLIED TO SAID SECOND RESERVOIR BY AN INCREASE IN THE RATE OF SAID ROTATION OF SAID VARIABLY DRIVEN ROLL, AND SUCH THAT, WITH SAID SECOND RESERVOIR SUBSTANTIALLY EMPTY, SAID LIQUID IS TRANSFERRED FROM SAID RESERVOIR TO SAID WEB MATERIAL BY SAID TRANSFERRING MEANS AT A RATE LESS THAN AT WHICH IT IS SUPPLIED TO SAID SECOND RESERVOIR BY A DECREASE IN SAID RATE OF ROTATION OF SAID ROLL.