# US 11,906,915 B2 · Fuser power reduction controller > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,906,915 B2 - Document ID: US11906915B2 - Status: Granted - Kind: B2 - Application number: 17/242,348 - Filed: 2021-04-28 - Published: 2022-11-03 - Granted: 2024-02-20 - Earliest claimed: 2021-04-28 - Assignees: Xerox Corporation - Applicants: Xerox Corporation - Inventors: Michael J. Wilsher; John R. Washington; Graeme A. Adams - Web page: https://patentgrep.com/patent/US11906915B2 ## CPC - G03G 15/2039: {with means for controlling the fixing temperature} - G03G 15/205: {specially for the mode of operation, e.g. standby, warming-up, error (G03G15/2046 takes precedence)} - B41J 29/393: Devices for controlling or analysing the entire machine {; Controlling or analysing mechanical parameters involving printing of test patterns} - G03G 15/5004: {Power supply control, e.g. power-saving mode, automatic power turn-off} - G03G 15/5087: {for receiving image data} - G03G 15/556: {for toner consumption, e.g. pixel counting, toner coverage detection or toner density measurement} - G03G: ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY - B41J: TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS ## Abstract Printing apparatuses include a photoreceptor adapted to print an image by applying marking material to print media, a fuser adapted to heat the marking material on the print media, and a controller. The controller determines the amount of marking material per unit area of the image before the fuser heats the marking material on the print media. The controller rasterizes the image to produce a bitmap of the image, but the amount of marking material per unit area for the image is determined before completion of rasterization and marking of the image. The controller also adjusts the operating temperature of the fuser to a fusing temperature based on the amount of marking material per unit area of the image, causes the photoreceptor to print the image on the print media using the bitmap of the image, and causes the fuser to fuse the marking material to the print media. ## Claims ### Claim 1 A printing apparatus comprising: a marking material application device adapted to print a print image by applying marking material to print media; a heating device adapted to heat the marking material on the print media; and a controller adapted to: determine an amount of marking material per unit area of the print image before rasterization of the print image by lowering resolution of the print image to a reduced resolution image and determining the amount of marking material per unit area based on image pixels of the reduced resolution image; rasterize the print image to produce a bitmap of the print image after determining the amount of toner per unit area; adjust an operating temperature of the heating device to a fusing temperature based on the amount of marking material per unit area of the print image; cause the marking material application device to print the print image on the print media using the bitmap of the print image; and cause the heating device to fuse the marking material to the print media at the fusing temperature. ### Claim 2 (depends on 1) The printing apparatus according to claim 1, wherein the controller is adapted to evaluate the image pixels of the reduced resolution image, wherein each of the image pixels is a distinct area of averaged marking material coverage. ### Claim 3 (depends on 2) The printing apparatus according to claim 2, wherein the controller is adapted to set the amount of marking material per unit area of the print image equal to one of the image pixels of the reduced resolution image that has a highest of the averaged marking material coverage. ### Claim 4 The printing apparatus according to claim, 1 wherein the controller is adapted to reduce the resolution of the print image to a resolution that maintains a number of pixels of the reduced resolution image below a pixel maximum. ### Claim 5 (depends on 1) The printing apparatus according to claim 1, wherein the controller is adapted to cause the marking material application device to print the print image only when the operating temperature of the heating device is at the fusing temperature and higher temperatures. ### Claim 6 (depends on 1) The printing apparatus according to claim 1, wherein the controller is adapted to reduce the fusing temperature of the heating device for relatively lower amounts of the marking material per unit area and to increase the fusing temperature of the heating device for relatively higher amounts of the marking material per unit area. ### Claim 7 A printing apparatus comprising: a photoreceptor adapted to print a print image by applying toner to print media; a fuser adapted to apply heat and pressure on the toner on the print media to fuse the toner to the print media; and a controller adapted to: determine an amount of toner per unit area of the print image before rasterization of the print image by lowering resolution of the print image to a reduced resolution image and determining the amount of toner per unit area based on image pixels of the reduced resolution image; rasterize the print image to produce a bitmap of the print image after determining the amount of toner per unit area; adjust an operating temperature of the fuser to a fusing temperature based on the amount of toner per unit area of the print image; cause the photoreceptor to print the print image on the print media using the bitmap of the print image; and cause the fuser to fuse the toner to the print media at the fusing temperature. ### Claim 8 (depends on 7) The printing apparatus according to claim 7, wherein the controller is adapted to evaluate the image pixels of the reduced resolution image, wherein each of the image pixels is a distinct area of averaged marking material coverage. ### Claim 9 (depends on 8) The printing apparatus according to claim 8, wherein the controller is adapted to set the amount of marking material per unit area of the print image equal to one of the image pixels of the reduced resolution image that has a highest of the averaged marking material coverage. ### Claim 10 (depends on 7) The printing apparatus according to claim 7, wherein the controller is adapted to reduce the resolution of the print image to a resolution that maintains a number of pixels of the reduced resolution image below a pixel maximum. ### Claim 11 (depends on 7) The printing apparatus according to claim 7, wherein the controller is adapted to cause the photoreceptor to print the print image only when the operating temperature of the fuser is at the fusing temperature and higher temperatures. ### Claim 12 (depends on 7) The printing apparatus according to claim 7, wherein the controller is adapted to reduce the fusing temperature of the fuser for relatively lower amounts of the toner per unit area and to increase the fusing temperature of the fuser for relatively higher amounts of the toner per unit area. ### Claim 13 A printing apparatus comprising: a photoreceptor adapted to print a print image by applying toner to print media; a fuser adapted to apply heat and pressure on the toner on the print media to fuse the toner to the print media; and a controller adapted to: determine an amount of toner per unit area of the print image before rasterization of the print image by lowering resolution of the print image to a reduced resolution image and using image pixels of the reduced resolution image; rasterize the print image to produce a bitmap of the print image after determining the amount of toner per unit area; adjust an operating temperature of the fuser to a fusing temperature based on the amount of toner per unit area of the print image; cause the photoreceptor to print the print image on the print media using the bitmap of the print image; and cause the fuser to fuse the toner to the print media at the fusing temperature. ### Claim 14 (depends on 13) The printing apparatus according to claim 13, wherein the controller is adapted to evaluate the image pixels of the reduced resolution image, wherein each of the image pixels is a distinct area of averaged marking material coverage. ### Claim 15 (depends on 14) The printing apparatus according to claim 14, wherein the controller is adapted to set the amount of marking material per unit area of the print image equal to one of the image pixels of the reduced resolution image that has a highest of the averaged marking material coverage. ### Claim 16 (depends on 13) The printing apparatus according to claim 13, wherein the controller is adapted to reduce the resolution of the print image to a resolution that maintains a number of pixels of a reduced resolution image below a pixel maximum. ### Claim 17 (depends on 13) The printing apparatus according to claim 13, wherein the controller is adapted to cause the photoreceptor to print the print image only when the operating temperature of the fuser is at the fusing temperature and higher temperatures. ### Claim 18 (depends on 13) The printing apparatus according to claim 13, wherein the controller is adapted to reduce the fusing temperature of the fuser for relatively lower amounts of the toner per unit area and to increase the fusing temperature of the fuser for relatively higher amounts of the toner per unit area.