Xerographic fixing apparatus

Claim 1

IN A XEROGRAPHIC APPARATUS INCLUDING MEANS TO REPRODUCE COPY IN THE FORM OF POWDER IMAGES HAVING A SOLVENT SOLUBLE COMPONENT LOOSELY ADHERING ON A WEB SHEET, MEANS TO ADVANCE THE SHEET, AND FUSING MEANS ADAPTED TO AFFIX THE POWDER IMAGE TO THE SURFACE OF THE SHEET DURING THE COURSE OF ITS MOVEMENT, AN IMPROVED FUSING MEANS COMPRISING THE COMBINATION: (A) AN ELONGATED FUSING CHAMBER INCLUDING SPACED TOP WALL, BOTTOM AND SIDE WALLS SECURED SUBSTANTIALLY VAPOR TIGHT TO EACH OTHER AND DEFINING AN INTERNAL GENERALLY UNOBSTRUCTED AND ENCLOSED PASSAGE EXTENDING AT LEAST PARTIALLY THE LENGTH THEREOF TO PERMIT A SUBSTANTIALLY UNIMPEDED VAPOR FLOW ALONG A SURFACE OF A WEB SHEET THEREIN; (B) AN ENTRANCE AND EXIT DEFINED BY AT LEAST ONE CHAMBER WALL AND CONNECTING TO SAID PASSAGE FOR THE PASSING OF A WEB SHEET THERETHROUGH; (C) A SOLVENT RESERVOIR ADJACENT THE PASSAGE OF SAID CHAMBER FOR CONTAINING A QUANTITY OF LIQUID SOLVENT FOR THE SOLUBLE COMPONENT OF THE POWER MATERIAL COMPRISING THE POWDER IMAGE; (D) DISPENSING MEANS EXTENDING FROM THE RESERVIOR INTO SAID DEFINED PASSAGE TO UNIFORMLY WIPE A METERED QUANTITY OF LIQUID SOLVENT FROM SAID RESERVIOR AGAINST AN ADVANCING PORTION OF THE NON-IMAGE SUPPORTING SURFACE OF THE MOVING WEB SHEET; (E) HEATING MEANS WITHIN SAID PASSAGE BEYOND SAID DISPENSING MEANS IN THE DIRECTION OF WEB MOVEMENT AND ADAPTED TO APPLY HEAT TO THE NON-IMAGE SUPPORTING SURFACE OF THE WEB AFTER APPLICATION OF LIQUID SOLVENT THERETO TO VAPORIZE SOLVENT FROM THE WEB; AND, (F) SEAL MEANS AT THE EXIT OF SAID CHAMBER TO SUBSTANTIALLY PREVENT THE SOLVENT VAPORIZED BY SAID HEATING MEANS FROM ESCAPING THEREPAST AND TO EFFECTIVELY CAUSE VAPORIZED SOLVENT TO DRIFT IN SAID PASSAGE AWAY FROM THE VICINITY OF SAID EXIT IN A DIRECTION TOWARD SAID ENTRANCE ALONG PORTIONS OF POWDER IMAGE ON THE WEB SHEET.