Patent Application
20060045583
The invention relates to cleaning deposits from rollers in a fusing apparatus for a printer.
Variable information may be added to media pre-printed, for example by offset lithography, using digital printing machines, such as the Digimaster® 9110 available from Nexpress Solutions LLC, Rochester, N.Y. Pre-printed media may generate an unacceptable level of contamination of a fuser in a printer, and in particular, on an externally heated roller fuser. With pre-printed media generated by an offset printing process, the contamination is caused by transfer of offset inks and spray powder to the fuser components, and in particular the fuser roller. Such contamination typically causes image defects and release failure of printed/fused materials from the fuser roller. This results in frequent service calls to replace fuser parts.
Various aspects of the invention are now presented with reference to the drawings, which are not drawn to any particular scale, and wherein like components in the numerous views are numbered alike. As used herein, “first”, “second”, and “third” are used for reference only, do not indicate any particular order, and are not intended to limit the invention. Referring now specifically to
The moving surface may be an outer circumferential surface of a roller 104 held by the support 102, the roller defining the circumferential surface and being rotatable about an axis 108 relative to the support 102. Another example of a moving surface is a fuser belt that defines the moving surface, which is also a fusing surface. A fuser belt system is disclosed in U.S. Pat. No. 6,096,427 issued Aug. 1, 2000 to Chen et al. This patent is hereby incorporated in its entirety by reference as if fully set forth herein. A fusing nip 148 may be formed with another roller 118, or a fuser belt.
A sheet S enters the fuser assembly 100 from the left through entry 126, passes through the fusing nip 148, and exits the fuser assembly 100 to the right through exit 128. Other configurations and are contemplated in the practice of the invention, the particular configuration not being critical in the practice of the invention. The sheet S has ink particles X deposited on it, for example by inkjet, electrographic, or other means that apply marking material to the sheet S, and the ink particles X may comprise ink, dye, and/or toner (fusible dry ink). The sheet S passes between the rollers 104 and 118 under pressure and/or heat, in the direction of arrow 130. This process fixes the ink particles X to the sheet S, as is well known in the art. As used herein “fuser” and “fusing” refers to apparatus and processes for stabilizing an image on a receiver by heat and/or pressure. Appropriate sheet handling apparatus (not shown) is provided within the fuser that carries the sheet S from the entry 126, through the nip between the rollers 104 and 118, and to the exit 128.
According to an aspect of the invention, a fusing process in a printer is provided comprising rotating the roller 104 held by the support 102 about the axis 108 relative to the support 102, the roller defining a circumferential surface 106. The common mount 150 is held by the support 102. The mount holds the first marginal end 202 of the first cleaning blade 112 that defines the first edge 114 opposite the first marginal end 202. The common mount 150 holds a second marginal end 204 of the second cleaning blade 120 that defines the second edge 122 opposite the second marginal end 204. The first edge 114 and the second edge 122 contact the circumferential surface 106.
According to an aspect of the invention, a fusing process in a printer is provided comprising moving a fusing surface (surface 106 for example) held by the support 102 in a direction 110 relative to the support 102. The support 102 holds the common mount 150 that holds the first marginal end 202 of the first cleaning blade 112 and the second marginal end 204 of the second cleaning blade 120. The first cleaning blade 112 defines the first edge 114 opposite the first marginal end 202, and the second cleaning blade 120 defines the second edge 122 opposite the second marginal end 204. The first edge 114 and the second edge 122 contact the fusing surface.
Referring now to
Referring now to
Referring now to
The cleaning device 200, 300, etc., may be constructed as separate replaceable units.
The moving surface 106 (circumferential surface, fusing surface, etc.) may comprise material deposited from pre-printed media, for example offset ink and/or powder. The powder is applied to inhibit smearing, offsetting, and blocking in an offset printing process, as is described on pages 176 and 249-250 of Hemult Kipphan, HANDBOOK OF PRINT MEDIA (Springer 2001), and is residual on pre-printed media. According to one aspect of the invention, the cleaning blades remove such material. Of course, the cleaning blades may be implemented to remove contamination from any source.
Referring now to
The material of cleaning blades 112, 120, etc., may be any material capable of withstanding the heat and abrasiveness of the fuser and/or pressure rollers or other surface to which it is applied. One example of a suitable material is a thin spring steel between 0.002 and 0.006 inches thick. A 0.004 inch thick extra spring temper cold rolled steel strip may be implemented. The included angle of contact between the blade and a tangent to the surface at the point of contact with the moving surface 106 may be on the order of 0 to 30 degrees, inclusive, and may be on the order of 10 to 20 degrees, inclusive. The tip force perpendicular to the moving surface 106 at the point of contact may be on the order of 1 ounce to 5 ounces per linear inch, inclusive, and may be between 2 ounces and 4 ounces per linear inch, inclusive.
The support 102 may take any suitable configuration. It generally comprises a frame and is composed of numerous separate components although a simple fuser may have a monolithic support. The support 102 may comprise one or more additional supports 132 (shown in phantom in
The fusing surface may be heated. Generally, heating is accomplished internally or externally. In the example of
Furthermore, a surface treatment may be applied to the moving surface 106 by a roller 136, as described in Provisional Patent Application Ser. No. 60/540,883 entitled “METHOD AND APPARATUS FOR VARIABLE WIDTH SURFACE TREATMENT APPLICATION TO A FUSER”, filed Jan. 30, 2004, the contents of which are hereby incorporated by reference as if fully set forth herein. As described in that application the surface treatment may be a substance that promotes release of the fused sheet from the fuser roller 104, for example silicone oil. The roller 136 may be a porous wick roller, for example a porous ceramic cylinder covered with fabric. Silicone oil may be fed to it from a perforated tube disposed inside the ceramic cylinder.
Additional cleaning may be added, as described in Provisional Patent Application Ser. No. 60/582,482 entitled “VARIABLE FUSER FOR PRINT MEDIA”, filed Jun. 24, 2004, the contents of which are hereby incorporated by reference as if fully set forth herein. In the embodiment of
The heating roller 134, roller 136, and cleaning assembly 138, may be held by one or more additional supports 132 (shown in phantom) that, in turn, are held by the support 102. The exact configuration is not critical in the practice of the invention to the extent that the components do not interfere with each other and the sheet S is free to move through the fuser assembly 100 without obstruction.
In the embodiments described herein with reference to
A fuser roller 104 may comprise a core, for example made of aluminum, and a cylindrical fusing blanket supported on the core. The blanket is typically made of an elastomeric material such as rubber particularly formulated to be heat conductive or heat insulative dependent upon whether the fuser heat source is located within the core or in juxtaposition with the periphery of the blanket. An example of a fuser roller is disclosed in United Patent Application Publication U.S. 2004/0023144 A1, filed Aug. 4, 2003, in the names of Jerry A. Pickering and Alan R. Priebe, the contents of which are incorporated by reference as if fully set forth herein. The pressure member 118 may be similarly constructed, for example a metallic core (such as aluminum) covered by an elastomeric cushion (such as filled silicone elastomer), covered by a perfluoroalkoxy or tetrafluoroethylene plastic sleeve.
The cleaning blades of the invention may be mounted in numerous suitable ways, for example by retaining and/or clipping. The blades tend to heat during operation, so relatively large contiguous blades may be mounted in a manner that permits thermal expansion and contraction relative to the mount, for example a retainer with mounting holes elongated in a widthwise direction would allow the blade to expand and contract in the widthwise direction while remaining fully constrained. This may also be applied to narrower blades to the extent that relief for thermal expansion and contraction is desired.
According one aspect of the invention, the cleaning device is conformable to a surface to be cleaned. The cleaning device may be conformable across the width of a roller (or other moving surface) such as a heater roller or a pressure roller, and may be rendered more conformable than a single piece blade extending across the same widthwise distance. This feature may improve the cleaning characteristics of the cleaning device.
The claims should not be read as limited to the described order or elements unless stated to that effect. As used herein, “first”, “second”, and “third” are used for reference only, do not indicate any particular order, and are not intended to limit the invention. In addition, use of the term “means” in any claim is intended to invoke 35 U.S.C. §112, paragraph 6, and any claim without the word “means” is not so intended.
Although the invention has been described and illustrated with reference to specific illustrative embodiments thereof, it is not intended that the invention be limited to those illustrative embodiments. Those skilled in the art will recognize that variations and modifications can be made without departing from the true scope and spirit of the invention as defined by the claims that follow. It is therefore intended to include within the invention all such variations and modifications as fall within the scope of the appended claims and equivalents thereof.
