Patent Application
20080138127
This application claims the benefit of Korean Patent Application No. 2006-123933, filed Dec. 7, 2006, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference.
1. Field of the Invention
Aspects of the present invention relate to a fuser cleaning apparatus and a method of operating a fuser cleaning apparatus for use with an image forming device, in which a contaminated fuser of the image forming device is cleaned by a heating of a heating roller of the fuser while the heating roller is not in motion.
2. Description of the Related Art
In an electro-photographic image forming device, a latent image is formed on a photosensitive drum to which toner is adhered. The toner is developed into a visible image using developer and the visible toner image is then transferred to a print medium, such as paper or a transparency. The image transferred to the print medium is fixed to the print medium by passing the print medium through a fuser. Once the print medium has passed through the fuser, the print medium is discharged from the image forming apparatus.
The fuser applies heat and pressure to the print medium to fix the image to the print medium. To this end, the fuser includes a heating roller to apply heat to the print medium and a pressure roller to apply pressure to the print medium. The heating roller and the pressure roller are provided along a conveyance path of the print medium.
As a result, it is frequently necessary to clean a fuser that becomes contaminated with toner. According to a conventional method of cleaning a fuser, a fusing temperature of the fuser is set to a high preset temperature in a cleaning mode via a heating of the heating roller while rotating the heating and pressure rollers. When the fusing temperature reaches the preset temperature, the medium (i.e., a sheet of paper) is picked up and passed between the heating and pressure rollers to remove melted toner.
The fuser further includes a guide member, which is referred to as a claw, to smoothly discharge media while preventing them from being wound around the photosensitive drum. As the number of sheets of media printed on increases, an increasing amount of toner that attaches to the guide member ends up being fixed to the guide member due to the fusing temperature increases during fusing processes. However, according to the conventional cleaning method, melting toner contaminants on the guide member is difficult since the cleaning operation is performed while the heating roller rotates. Rather, toner contaminants on the heating and pressure rollers may be added to toner contaminants on the guide member.
Thus, the conventional cleaning method is not effective to clean contaminants on the guide member. If the contaminants fixed to the guide member scratch a medium to be discharged, undesired vertical black lines may be printed on the medium and the medium may also be jammed.
Therefore, it is an aspect of the invention to provide a fuser cleaning apparatus and a method of operating a fuser cleaning apparatus for use with an image forming device in which media are prevented from being scratched and jammed during fusing processes due to residual contaminants on a guide member which are hard to clean.
In accordance with an aspect of the invention, there is provided a fuser cleaning apparatus, the apparatus comprising a fuser including a guide member to guide a print medium conveyed through the image forming device, and heating and pressure rollers to fix an image to the print medium; a power source to power the conveyance of the print medium and to rotate the fuser; a heater to heat the heating roller to melt contaminants fixed to the guide member; and a controller to drive the heater while the fuser is not rotated and to pass the print medium through the fuser to remove the melted contaminants from the guide member.
In accordance with an aspect of the invention, there is provided a fuser cleaning method for use with an image forming device comprising a fuser including a guide member and heating and pressure rollers to fix an image transferred to a print medium, the method comprising: heating the fuser, when a cleaning mode for the fuser has been set, by driving a heater thereof while the fuser does not rotate to melt contaminants on the guide member; and passing the print medium through the fuser to absorb and remove the melted contaminants.
In accordance with an aspect of the invention, there is provided a method of operating a cleaning mode of a fuser of an image forming apparatus, comprising: setting a fuser cleaning temperature; activating a power source of the image forming apparatus to convey the print medium through the apparatus to a first position; when the print medium reaches the predetermined position, deactivating the power source and activating a heater of the fuser to heat the fuser; when the temperature of the fuser reaches the fuser cleaning temperature, reactivating the power source to convey the print medium to a second position and deactivating the heater; and when the print medium reaches the second position, ending the cleaning mode.
Additional and/or other aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.
These and/or other aspects and advantages of the invention will become apparent and more readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:
Reference will now be made in detail to the present embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the like elements throughout. The embodiments are described below in order to explain the present invention by referring to the figures.
The fuser 250 applies heat and pressure to the paper carrying the transferred toner image so as to fix the toner image to the paper. The fuser 250 includes a heating roller 251 to generate high heat and a pressure roller 252 that is in close contact with the heating roller 251. The heating roller 251 includes a heater 253 to generate the high heat. A heating lamp provided in the heating roller 251 or an electric heating coil inserted between inner and outer circumferential surfaces of the heating roller may be used as the heater 253. The fuser 250 also includes a temperature sensor 291 provided near the heating roller 251 to sense the temperature of the surface of the heating roller. The pressure roller 252 closely contacts the heating roller 251 at a constant pressure and rotates at the same speed as the heating roller 251.
The pickup roller 261 is provided at a beginning position of a paper conveyance path P to pick up each sheet of paper from a paper feed cassette (not shown) in which sheets of paper are stacked. The paper conveyance path P is a path along which the paper is conveyed until the paper is discharged through paper exit rollers 266, 267, 268, and 269 after being picked up by the pickup roller 261. Conveying rollers 262 and 263, which convey the picked-up sheet of paper, registration rollers 264 and 265, which align the front end of the sheet of paper that is being conveyed, the paper exit rollers 266, 267, 268, and 269, which discharge the sheet of paper, the photosensitive drum 220, the transfer roller 240, and the fuser 250 are provided along the paper conveyance path P.
The paper feed sensor 271 senses a sheet of paper that is being conveyed and is provided near the registration rollers 264 and 265 to sense that the sheet of paper is moving to the photosensitive drum 220. The paper feed sensor outputs a first sensed signal. The first sensed signal is used to determine exposure and developing timings.
A paper exit sensor 272 is provided in the paper conveyance path P downstream of the paper feed sensor 271, and, more specifically, downstream of the fuser 250. The paper exit sensor 272 senses a sheet of paper that passes through the fuser 250 and outputs a second sensed signal. The second sensed signal is used to determine the time to complete printing.
The first and second motors 281 and 282 respectively transfer motive force to the components. The first motor 281 is connected to the photosensitive drum 220 and the components (i.e., the developing roller 230, the transfer roller 240, the registration rollers 264 and 265, the conveying rollers 262 and 263, and the pickup roller 261) that are provided in the paper conveyance path P upstream of the photosensitive drum 220. The second motor 282 is a drive source to drive the components (i.e., the heating roller 251, the pressure roller 252, and the paper exit rollers 266, 267, 268, and 269) that are provided in the paper conveyance path P downstream of the photosensitive drum 220.
The fuser cleaning apparatus of the present invention includes a controller 201 to control overall operations of the fuser cleaning apparatus as shown in
Although fuser cleaning operations may be performed each time a printing operation is performed, it is more effective to perform fuser cleaning operations when a fuser cleaning mode has been set. The fuser cleaning mode may be set based on the type and size of the product and/or on the number of printed sheets of paper. Taking into consideration the fact that printing of tens of thousands of sheets severely contaminates a guide member of the fuser, the setting of the fuser cleaning mode on the number of printed sheets may be advantageous.
The fuser cleaning mode may be set directly by the user through the host computer 100 or may be automatically set when the total number of printed sheets of paper counted in printing operations reaches a preset number. When the fuser cleaning mode is automatically set, the controller 201 uses print count information that is obtained by counting, through a counter 202, the total number of sheets of paper printed in printing operations.
If the fuser is significantly contaminated as a result of the performance of a number of printing operations, it is necessary to perform a fuser cleaning operation to separate toner remnants B that may be fixed to a guide member 254 from the guide member 254 as shown in
At time Ta when the sheet of paper S reaches a specific position A, the controller 201 turns off the first motor 281 (see
As the sheet of paper S passes between the heating roller 251 and the pressure roller 252, the paper S absorbs and removes toner remnants B that have been melted from the guide member 254 (see
According to an embodiment of the present invention, the controller 201 sets the fuser cleaning mode according to a cleaning mode setting command input from the host computer 100. According to an alternate embodiment, the controller 201 determines whether to set the fuser cleaning mode according to the number of printed sheets counted by the counter 202.
If the fuser cleaning mode is set, the controller 201 then performs a fuser cleaning operation to clean contaminants on the fuser as shown in
First, the controller 201 sets a fuser cleaning temperature Hc to be higher than a fusing temperature set to be appropriate for printing (301). The controller 201 turns the first motor 281 on, turns the second motor 282 off, and turns the heater 253 (303) on. Accordingly, the heating roller 251 is heated by the heater 253 while the heating roller 251 is not in motion and a sheet of paper S is picked up and conveyed along the paper conveyance path P.
While the sheet of paper S is conveyed, the controller 201 determines whether the sheet of paper S has been detected by the paper feed sensor 271 (305). If the sheet of paper S is determined to have been detected, the controller 201 counts an elapsed time T using an internal timer (307) and determines whether the counted time T has reached a preset time Ta. The preset time Ta corresponds to the time required for the sheet of paper S to reach the specific position A from the paper feed sensor 271.
When the elapsed time T has reached the preset time Ta, the controller 201 determines whether a surface temperature H of the heating roller 251 sensed by the temperature sensor 291 has reached the preset cleaning temperature Hc (313). If the surface temperature H is determined to have not reached the preset cleaning temperature Hc, the controller 201 returns to operation 311 to maintain the heating operation.
If the surface temperature H is determined to have reached the preset cleaning temperature Hc, the controller 201 turns the first and second motors 281 and 282 on and turns the heater 253 off (315). Accordingly, the sheet of paper introduced between the heating roller 251 and the pressure roller 252 absorbs and removes toner remnants on the guide member 254 that are melted from the guide member 254 by the heating of the heating roller 251.
The controller 201 then determines whether the sheet of paper has been detected by the paper exit sensor 272 (317). If the sheet of paper is determined to have been detected by the paper exit sensor 272, the controller 201 returns to operation 315 to maintain the cleaning operation so as to absorb and remove toner remnants from the paper guide memory 254.
If the determination of operation 317 is that the sheet of paper has been detected by the paper exit sensor 272, the controller 201 determines that the toner remnants absorption and removal operation has been completed and terminates the cleaning operation.
Although the first and second motors 281 and 282 are used as driving sources to drive the components in the above embodiments, according to another embodiment of the invention, the paper pickup, conveyance, development, transfer, fusing, and exit processes may be performed using a single motor.
Another embodiment of the invention is shown in
As shown in
As shown in
Reference will now be made to
While the sheet of paper S is conveyed, the controller 201 determines whether the sheet of paper S has been detected by the paper feed sensor 271 (405). If the sheet of paper S has been determined to be detected, the controller 201 counts an elapsed time T using an internal timer (407) and determines whether the counted time T has reached a preset time Ta. The preset time Ta corresponds to the time required for the sheet of paper S to reach the specific position A from the paper feed sensor 271.
When the elapsed time T has reached the preset time Ta, the controller 201 turns the integrated motor 283 off and turns the heater 253 on. Accordingly, the heating roller 251 is heated by the heater 253 while the heating roller 251 is not in motion and the sheet of paper S waits at the specific position A.
The controller 201 then determines whether a surface temperature H of the heating roller 251 that is sensed by the temperature sensor 291 has reached the preset cleaning temperature Hc (413). If the surface temperature H is determined to have not reached the preset cleaning temperature Hc, the controller 201 returns to operation 411 to maintain the heating operation.
If the determination of operation 413 is that the surface temperature H has reached the preset cleaning temperature Hc, the controller 201 turns the integrated motor 283 on and turns the heater 253 off (415). Accordingly, the sheet of paper introduced between the heating roller 251 and the pressure roller 252 absorbs and removes toner remnants that are melted from the guide member 254 by heating of the heating roller 251.
The controller 201 then determines whether the sheet of paper has been detected by the paper exit sensor 272 (417). Depending on this determination, the controller 201 returns to operation 415 to maintain the cleaning operation or terminates the cleaning operation.
As is apparent from the above description, aspects of the present invention provide a fuser cleaning apparatus and method of operating a fuser cleaning apparatus for use with an image forming device which have a variety of advantages. For example, heat is efficiently transferred to a guide member of a fuser to allow for relatively easy performance of a cleaning operation of the fuser since a heating roller of the fuser is heated by a heater while the heating roller is not in motion. Also, it is possible to prevent melted toner remnants from contaminating the heating roller since a sheet of paper which has waited at an entrance of the fuser is conveyed and passed between the heating and pressure rollers of the fuser after the heating roller is heated while the heating roller is not in motion.
Although a few embodiments of the present invention have been shown and described, it would be appreciated by those skilled in the art that changes may be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the claims and their equivalents.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2006-123933 | Dec 2006 | KR | national |
