Image transport fusing system
AssigneeDelphax Systems
InventorJeffrey J. Carrish
Life of this patent
Estimating the term…
Abstract
Fusing apparatus for an electrographic printer, includes an abhesive belt for carrying and contacting a recorded image, a low temperature heater to fuse the image, and an assembly for synchronously moving a sheet in contact with the belt past the heater for an extended dwell time so that the toned image attains a fusing temperature as it resides in thermal contact with the heater along an extended transport path. The belt has a release coating of low surface free energy. Image transfer or fusing may be accomplished at sufficiently low belt temperatures that a single belt may be employed to effect imaging, toning, image transfer and fusing steps without impairing heat-sensitive toning assemblies, photoconducting elements, or other temperature-sensitive parts of the printer.
Claims20
A heat fusing apparatus comprising
- a belt having a non-tacky surface which is abherent with respect to a melted toner, said belt extending the width of a recording sheet
- heating means for providing heat to a region of the belt having an area between approximately one third and several times as large as a printable area of the recording sheet, the heat heating the belt to a temperature not substantially above a melt temperature of a toner forming a toned image on the recording sheet, and
- means for thermally contacting a toned side of the recording sheet to the abherent surface of the belt and synchronously moving the belt and the recording sheet such that an extend region of each is in contact as they move past the heating means so that the recording sheet attains the melt temperature of the toner whereby the toned image is efficiently and cleanly fused to the recording sheet as a permanent print.
Printing apparatus, comprising
- charge writing means for forming a latent charge image
- developing means for toning the latent charge image to form a toned image
- means for applying the toned image to a recording sheet
- a belt assembly including a belt having a release surface which is abherent to melted toner and at least one pair of spaced apart rollers about which the belt is driven in a circuit for carrying the recording sheet
- heating means maintained at temperature not substantially over a toner fusing temperature and positioned for heating the belt to said toner fusing temperature in a heated portion of the circuit extending over an area comparable to the area of the recording sheet, and
- press means for urging the recording sheet into contact with the belt while the sheet moves synchronously with the belt through the heated portion of the circuit so that the image is brought to the toner fusing temperature by thermally contacting the belt release surface and is fused to the sheet.
A heat fusing apparatus comprising
- a belt extending the width of a recording sheet and having a surface release property with respect to melted toner
- heating means for providing heat to region of the belt extending entirely across an intended print area, the heat being controlled to a temperature not substantially above a melt temperature of the toner, and
- means for moving the belt to transport a recording sheet such that the belt and recording sheet move synchronously in contact with each other on an extended region of the sheet past the heater means for a dwell time effective for the sheet to substantially attain thermal equilibrium with the belt at the melt temperature of the toner, the belt pressing the sheet and thereby fusing a toner image to the recording sheet.
Dependencies are inferred from the claim text.