WO2004099883A1 - 画像形成装置 - Google Patents
画像形成装置 Download PDFInfo
- Publication number
- WO2004099883A1 WO2004099883A1 PCT/JP2004/006366 JP2004006366W WO2004099883A1 WO 2004099883 A1 WO2004099883 A1 WO 2004099883A1 JP 2004006366 W JP2004006366 W JP 2004006366W WO 2004099883 A1 WO2004099883 A1 WO 2004099883A1
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- WO
- WIPO (PCT)
- Prior art keywords
- image
- sheet
- image forming
- detection
- recording paper
- Prior art date
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Classifications
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N1/00—Scanning, transmission or reproduction of documents or the like, e.g. facsimile transmission; Details thereof
- H04N1/00681—Detecting the presence, position or size of a sheet or correcting its position before scanning
- H04N1/00684—Object of the detection
- H04N1/00687—Presence or absence
- H04N1/00694—Presence or absence in an input tray
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- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
- G03G15/00—Apparatus for electrographic processes using a charge pattern
- G03G15/04—Apparatus for electrographic processes using a charge pattern for exposing, i.e. imagewise exposure by optically projecting the original image on a photoconductive recording material
- G03G15/04018—Image composition, e.g. adding or superposing informations on the original image
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N1/00—Scanning, transmission or reproduction of documents or the like, e.g. facsimile transmission; Details thereof
- H04N1/00681—Detecting the presence, position or size of a sheet or correcting its position before scanning
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N1/00—Scanning, transmission or reproduction of documents or the like, e.g. facsimile transmission; Details thereof
- H04N1/00681—Detecting the presence, position or size of a sheet or correcting its position before scanning
- H04N1/00742—Detection methods
- H04N1/00745—Detecting the leading or trailing ends of a moving sheet
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N1/00—Scanning, transmission or reproduction of documents or the like, e.g. facsimile transmission; Details thereof
- H04N1/00681—Detecting the presence, position or size of a sheet or correcting its position before scanning
- H04N1/00763—Action taken as a result of detection
- H04N1/00774—Adjusting or controlling
- H04N1/00779—Adjusting settings, e.g. mode, feeding rate or type of paper
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N1/00—Scanning, transmission or reproduction of documents or the like, e.g. facsimile transmission; Details thereof
- H04N1/46—Colour picture communication systems
- H04N1/50—Picture reproducers
- H04N1/506—Reproducing the colour component signals picture-sequentially, e.g. with reproducing heads spaced apart from one another in the subscanning direction
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- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
- G03G2215/00—Apparatus for electrophotographic processes
- G03G2215/04—Arrangements for exposing and producing an image
- G03G2215/0429—Changing or enhancing the image
- G03G2215/0431—Producing a clean non-image area, i.e. avoiding show-around effects
- G03G2215/0434—Parameters defining the non-image area to be cleaned
- G03G2215/0443—Copy medium outline relative to the charge image
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N1/00—Scanning, transmission or reproduction of documents or the like, e.g. facsimile transmission; Details thereof
- H04N1/04—Scanning arrangements, i.e. arrangements for the displacement of active reading or reproducing elements relative to the original or reproducing medium, or vice versa
- H04N1/12—Scanning arrangements, i.e. arrangements for the displacement of active reading or reproducing elements relative to the original or reproducing medium, or vice versa using the sheet-feed movement or the medium-advance or the drum-rotation movement as the slow scanning component, e.g. arrangements for the main-scanning
Definitions
- the present invention relates to an electrophotographic image forming apparatus, and more particularly, to a measure for reducing the amount of developer collected without being transferred to a sheet as much as possible.
- an electrostatic latent image is created on the basis of image data input on an image carrier, and the electrostatic latent image is developed (developed) by a developing device.
- a developer image is formed on the image carrier.
- the developer image formed on the image carrier is transferred to a conveyed sheet, and then the developer image is melted with heat and pressure by a fixing device to be fixed on the sheet.
- the position of the read original image and the position of the created image The position will be different.
- the sheet transport deviation is not constant, and varies depending on the size and type of the sheet or the storage means in which the sheet is stored. Therefore, if a misalignment occurs between the developer image and the sheet when performing borderless image formation (full-surface image formation) for forming an image on the entire surface of the sheet, the image transferred to the sheet will be chipped. However, the resulting image is very unsightly.
- a large-size image (developer image) with a margin on the image carrier is taken into account in consideration of a positional shift due to a sheet transport deviation between the developer image on the image carrier and the sheet. In such a case, even when a sheet is shifted in conveyance, a good image without any chipping can be formed.
- the developer collected by the tally-engaging means without being transferred to the sheet is generated. More and more recovered development In an image forming apparatus in which the developer cannot be reused, the recovered developer is discarded, which is extremely uneconomical, and the cycle until the recovered developer is full becomes very short.
- the tally means c provided with a container a for recovering the developer t on the transfer belt d that conveys the sheet p by sucking and conveying the sheet p is provided with the collected developer t.
- a detecting means for detecting an end position of a sheet conveyed toward a transfer point is provided upstream of a transfer point for transferring an image formed on an image carrier to a sheet in a sheet conveying direction.
- the size of the image on the image carrier is determined based on the size of the sheet whose end position has been detected by the detection means, and the sheet is formed according to the image formed on the image carrier after the size is determined.
- an image on the image carrier an image of a size corresponding to the size of the conveyed sheet is formed on the image carrier, and the image is not transferred to the sheet, and is not transferred to the sheet by tallying means. It is known to reduce the amount of developer collected (for example, see Japanese Patent Application Laid-Open No. 10-186951).
- the image is formed on the image carrier after the size of the image on the image carrier is determined after the detection of the sheet end position by the detecting device. Also needs to be provided considerably upstream in the sheet conveyance direction. In this case, the sheet conveyance path from the detection point of the sheet edge position by the detection means to the transfer point must be considerably long in the sheet conveyance direction, and the size of the image forming apparatus becomes very large. In addition, the longer the sheet conveyance path from the detection point of the detection means to the transfer point, the longer the time required for image formation.
- the detection accuracy of the sheet end position by the detection means decreases, and the sheet is shifted due to the sheet conveyance deviation.
- the image of the sheet may be chipped, if the detection means is moved closer to the transfer point, the sheet 2004/006366
- a registration means which is a timing adjusting means for adjusting the position of an image formed on the image carrier and the conveyed sheet. After stopping the conveyed sheet once, the sheet is restarted at the same timing.
- This registration means has not only the function of adjusting the timing with the image on the image carrier, but also the function of correcting the skew (inclination conveyance) of the conveyed sheet.
- the present invention has been made in view of such a point, and an object of the present invention is to shorten a sheet conveyance path from a detection point to a transfer point so that a sheet end position by a detection unit or a sheet end position is detected. While ensuring the detection accuracy of the position and skew state, the compactness is achieved, the developer collected by the greening means is reduced as much as possible, and the cycle until the developer is full is extended, and the cleaning failure is reduced.
- An object of the present invention is to provide an image forming apparatus which can effectively prevent the image forming apparatus.
- the image forming apparatus of the present invention forms an image on an image carrier based on input image data, transfers the image to a conveyed sheet, T / JP2004 / 006366
- An image forming apparatus for forming an image on the image carrier, and conveying the image formed on the image carrier to a transfer point upstream of a transfer point for transferring the image to the sheet toward the transfer point.
- Detecting means for detecting an end position of the sheet to be transferred, wherein when the size of the image on the image carrier is larger than the size of the sheet conveyed toward the transfer point, the detecting means The size of the image on the image carrier transferred to the middle of the sheet after the detection of the sheet edge position is changed based on the detection result by the detecting means, and the size of the image on the image carrier having the changed size is changed.
- the image formation on the sheet thereafter is continuously performed in accordance with the image of (1).
- the image conveyed to the transfer point with respect to the sheet conveyed to the image carrier is larger than the sheet size.
- the size of the image on the image carrier transferred to the middle of the sheet is changed based on the detection result.
- the size of the image formed on the image carrier is changed before and after the detection of the sheet end position by the detection means is obtained. Therefore, even before the end position of the sheet is detected before the detection by the detection unit, the image on the image carrier that is larger than the sheet size is used to detect the image due to the sheet conveyance deviation.
- the size of the image on the image carrier is determined based on the detection result of the end position of the sheet. Is changed to a size according to the end position of the sheet.
- the amount of the developer that is not transferred to the sheet and collected by the cleaning unit is reduced as much as possible, and it is possible to suppress the waste of the developer and economically consume the developer.
- the tallying unit in which the container for collecting the collected developer is integrated the bias of the developer in which the collected developer partially accumulates is suppressed, and the part of the collected developer is suppressed. Cleaning by Leakage Defects can be prevented.
- the detection means can be provided close to the transfer point. Therefore, the conveyance path of the sheet from the detection point of the sheet end position by the detection means to the transfer point is shortened in the sheet conveyance direction, and the image forming apparatus can be made compact. In addition to this, the time required for image formation can be shortened.
- the image formed on the image carrier before the detection of the position of the sheet edge by the detecting means may be configured to detect a shift in conveyance of the sheet conveyed toward the transfer point. It may be characterized in that it is set to a large size with a margin in consideration.
- the image on the image carrier having a large size with a margin causes the sheet conveyance deviation. It is possible to reliably prevent image chipping and transfer a better image onto the sheet.
- the detecting means corrects the sheet conveying inclination before the detecting of the sheet end position by the detecting means, and the image of the image on the image carrier with respect to the sheet. It may be provided on the downstream side of the registration means for adjusting the position.
- the registration means corrects the oblique conveyance of the sheet conveyed toward the transfer point.
- the end position of the sheet is detected in a state where the sheet is conveyed substantially straight, and the end position of the sheet is detected with high accuracy.
- the size of the image having a margin on the image carrier formed before the detection of the image is also reduced as much as possible. For this reason, the amount of waste developer collected without being transferred to the sheet is reduced, and the cycle of the cleaning unit until the developer collection container is full can be made longer. 2004/006366
- the distance from the detection point by the detection means to the transfer point is shorter than the distance from the image writing point to the image carrier to the transfer point.
- the size of the image formed on the image carrier before the detection of the position of the sheet end by the detection means is set based on predetermined data.
- the size of the image on the image carrier after the detection of the position of the sheet edge may be changed based on the detection result of the detection means.
- the distance from the detection point by the detection unit to the transfer point is set to be shorter than the distance from the image writing point to the image carrier to the transfer point.
- the detection of the end position of the sheet by the detection means can be performed at an early stage, and the size of the image on the image carrier is quickly changed based on the detection result of the end position of the sheet after the detection by the detection means. Will be. As a result, the amount of waste developer collected without being transferred to the sheet becomes smaller, and the cycle until the developer collection container of the tally Jung means becomes full can be further lengthened.
- the image forming apparatus further includes a plurality of image carriers that are arranged in parallel in a conveying direction of the sheet carrier that carries and conveys the sheet, and that individually form images on the sheet.
- the size of the image on the image carrier located on the most upstream side in the sheet conveying direction of the carrier is changed during the image formation after the detection of the sheet end position by the detection means, while remaining the size of the image on the image carrier, according to the image forming apparatus which may c this invention is characterized in that to change previously image formed based on the detection result of the sheet end portion location by the detecting means
- an upper position is determined based on the detection result of the sheet end position by the detection means.
- the timing for changing the size of the image on the image carrier is different from the timing for forming an image on each of the image carriers.
- the image bearing member located at the most upstream side in the sheet conveying direction.
- the size of the image is changed during the image formation after the detection of the sheet edge position by the detection means, but in the other remaining image carriers, the image is placed on each of the image carriers.
- an image having a size (a size as small as possible) based on the detection result of the sheet end position by the detection means is formed. As a result, the amount of waste developer collected without being transferred to the sheet is effectively reduced, and the cycle until the developer collection container of the cleaning unit is filled can be lengthened.
- one of the image carriers may have a correction for correcting a displacement of an image forming position of the remaining image carriers with respect to the one image carrier.
- the size of the image formed on each of the image carriers is set based on the detection result of the sheet edge position by the detection means and the correction data. It may be.
- an image forming position shift with respect to a reference image carrier in a tandem type image forming apparatus that is, a position shift, a position shift of a writing unit, a transfer belt conveyance inclination, and the like.
- Correction data for correcting misalignment, inclination, etc. of the other image carrier, and the sheet detected by the detection means provided in proximity to the image carrier located at the most upstream side in the sheet conveyance direction.
- the range of the image formed on each of the image carriers is set according to the detection result of the end position.
- a position or a magnification at which an image is formed on the image carrier is set based on predetermined data irrespective of a detection result of the sheet end position by the detection means. It may be characterized by being performed.
- the position and the magnification are changed when the range in which the image is formed on the image carrier is changed during the image formation on the sheet. If this is done, the continuity of the image will be lost or the image will be distorted, but if the position and magnification of the image are set based on the predetermined data, good image formation can be performed. It becomes possible.
- a borderless image forming mode for forming a borderless image on the sheet is provided so as to be selectable, and when the borderless image forming mode is selected, An image may be formed based on a detection result of the position of the sheet end by the detection unit.
- the image forming apparatus of the present invention it is possible to control the image forming range based on the detection result of the sheet edge position by the detecting means only by selecting the borderless image forming mode when forming the borderless image. Can be performed. As a result, while preventing the image on the sheet from being chipped, the amount of the unnecessary developer collected without being transferred onto the sheet is suppressed, and the cycle until the developer collection container of the cleaning unit is filled is completed. Can be lengthened.
- the detection unit when the size of the image on the image carrier is larger than the size of the sheet conveyed toward the transfer point, the detection of the sheet end position by the detection unit Further, the skew state of the sheet is detected, and the size of the image on the image carrier transferred to the middle of the sheet thereafter is determined by the detection means of the end position of the sheet and the detection result of the skew state. In accordance with the image on the image carrier whose size has been changed, so that the subsequent image formation on the sheet is continuously performed.
- the sheet conveyed toward the transfer point is larger than the sheet size.
- the image on the image carrier is transferred, and the end position and the skew state of the sheet are detected by the detection means, the image on the image carrier transferred to the middle of the sheet based on the detection result. Is resized. That is, the detection result of the edge position and skew state of the seat that by the said detection means at O and later before the following to be obtained, so that the size of an image formed on said image bearing member is changed c 6366
- the sheet is larger than the sheet size.
- the image on the image carrier it is possible to transfer a good image onto the sheet without causing the image to be chipped due to the skew of the sheet.
- the end position of the sheet and the skew state are not determined. Based on the detection result, the size of the image on the image carrier is changed to a size according to the end position of the sheet.
- the amount of the developer collected by the cleaning unit without being transferred to the sheet is reduced as much as possible, and it is possible to suppress the waste of the developer and economically consume the developer.
- the cleaning means in which the container for collecting the collected developer is integrated the bias of the developer in which the collected developer is partially increased is suppressed, and the collected developer is partially removed. It is possible to prevent cleaning failure due to leakage.
- the image is formed on the image carrier before the end position of the sheet and the skew state are detected by the detection means, it is possible to provide the detection means close to the transfer point. Become.
- the image formed on the image carrier before the end position of the sheet or the skew state is detected by the detection means is conveyed toward the transfer point.
- the sheet may be set to a large size with a margin in consideration of the sheet conveyance deviation. According to the image forming apparatus of the present invention, even if the detection result of the end position and the skew state of the sheet by the detection unit is not obtained, the image on the image carrier having a large size with a margin is provided.
- the detecting means may detect a position of an image on the image carrier with respect to the sheet before detecting an end position of the sheet or a skew state by the detecting means. It may be characterized in that it is provided downstream of the registration means for adjustment in the sheet conveying direction.
- the skew of the sheet conveyed toward the transfer point is corrected by the registration unit by positioning the detection unit downstream of the registration unit in the sheet conveyance direction. Is done.
- the end position and the skew state of the sheet are detected in a state where the skew of the sheet is substantially corrected, and the end position and the skew state of the sheet are detected with high accuracy.
- the size of the image having a margin on the image carrier formed before the detection of the end position of the sheet and the skew state by the detection means is reduced as much as possible. For this reason, the amount of waste developer collected without being transferred to the sheet is reduced, and the cycle of the cleaning unit until the developer collection container is full can be made longer.
- a distance from the detection point by the detection means to the transfer point is set to be shorter than a distance from the image writing point to the image carrier to the transfer point.
- the size of an image formed on the image carrier before the detection of the end position of the sheet and the skew state by the detection means is set based on predetermined data
- the size of the image formed on the image carrier after the detection of the edge position and the skew state of the sheet by the detection means is based on the detection result of the edge position and the skew state of the sheet by the detection means. May be changed.
- the distance from the detection point by the detection unit to the transfer point is set to be shorter than the distance from the writing point of the image to the image carrier to the transfer point. I have.
- the detection of the skew state at the end position of the sheet by the detection means can be performed at an early stage, 06366
- the size of the image on the image carrier is promptly changed based on the detection result of the end position of the sheet and the skew state by the detection means.
- the amount of waste developer collected without being transferred to the sheet becomes smaller, and the cycle until the developer collection container of the clearing means becomes full can be further lengthened.
- a distance from the detection point by the detection means to the transfer point is set to be shorter than a distance from the image writing point to the image carrier to the transfer point.
- the size of the image formed on the image carrier is set based on the detection result of the sheet end position by the detection means, and the skew state of the sheet is detected by the detection means. In this case, after the detection, the size of the image formed on the image carrier may be changed based on the detection result of the skew state of the sheet.
- the image forming apparatus of the present invention when detecting the skew state of the sheet, it is necessary to convey the sheet to some extent and to detect the end position by the detection means, so that the skew state of the sheet is It takes time to detect, and the skew state of the sheet is detected after the start timing of image formation.
- the skew state of the sheet is detected, the size of the image on the image carrier thereafter is quickly changed according to the skew state of the sheet, and the image is collected without being transferred to the sheet. The amount of waste developer can be reduced.
- the image forming apparatus further includes a plurality of image carriers that are arranged in parallel in a conveying direction of the sheet carrier that carries and conveys the sheet, and that individually form images on the sheet.
- the size of the image on the image carrier located on the most upstream side in the sheet conveyance direction of the carrier is determined based on the detection result of the end position of the sheet and the skew state by the detection means.
- the size of the remaining images on the image carrier which will be changed later, are determined based on the detection result of the end position of the sheet and the skew state by the detection means. It may be characterized in that it is changed before the start of image formation.
- the image forming apparatus of the present invention in a tandem type image forming apparatus having a plurality of image carriers, since the positions of the image carriers are different, the position of the end of the sheet by the detection means is different.
- the timing for changing the size of the image on the image carrier based on the detection result of the skew state is different from the timing for forming an image on each of the image carriers. Therefore, in the image carrier positioned at the most upstream side in the sheet conveying direction, after the start of image formation (during image formation), the detection result of the end position of the sheet by the detection means is obtained.
- the detection result of the end position and the skew state of the sheet by the detection unit is used. Based on this, an image of a size based on the size (a size with a margin as small as possible) is formed. As a result, the amount of waste developer collected without being transferred onto the sheet is effectively reduced, and the cycle until the developer collection container of the cleaning unit is filled can be lengthened. It becomes.
- one of the image carriers may have a correction for correcting a displacement of an image forming position of the remaining image carriers with respect to the one image carrier.
- the size of the image formed on each of the image carriers is set based on the detection result of the end position and the skew state of the sheet by the detection means and the correction data. It can be characterized by that.
- an image forming position shift with respect to a reference image carrier in a tandem type image forming apparatus that is, a position shift, a position shift of a writing unit, a transfer belt conveyance inclination, and the like.
- Correction data for correcting misalignment, inclination, etc. of the other image carrier, and the sheet detected by the detection means provided in proximity to the image carrier located at the most upstream side in the sheet conveyance direction.
- the size (range) of the image formed on each of the image carriers is set according to the end position and the detection result of the skew state. Accordingly, even if the image carrier other than the reference image carrier has a deviation or an inclination, etc.
- the image carrying the image in the smallest possible range for the sheet conveyed on the transfer carrier is carried out. It can be formed on the body.
- the position or magnification at which an image is formed on the image carrier is determined in advance irrespective of the end position of the sheet and the detection result of the skew state by the detection means. It may be characterized in that it is set based on the obtained data.
- the image forming apparatus of the present invention if the position or magnification is changed when changing the range of image formation on the image carrier during the image formation on the sheet, image continuity may be lost or the image may be lost. However, if the position and the magnification of the image are set based on the predetermined data, it is possible to form a good image.
- a borderless image forming mode for forming a borderless image on the sheet is provided so as to be selectable, and when the borderless image forming mode is selected, An image may be formed based on the detection result of the end position of the sheet and the skew state by the detection means.
- an image based on the detection result of the edge position and the skew state of the sheet by the detection means is only required to select the borderless image forming mode when forming the borderless image.
- the formation range can be controlled.
- FIG. 1 is a schematic diagram showing a schematic configuration of an image forming apparatus using an electrophotographic method according to a first embodiment of the present invention.
- FIG. 2 is a schematic diagram showing a configuration in the vicinity of the first and second photosensitive drums. 2004/006366
- FIG. 3 is a plan view of the vicinity of the line sensor as viewed from above.
- FIG. 4 is a block diagram illustrating a configuration of an image forming system of the image forming apparatus.
- FIG. 5 is an explanatory diagram illustrating an image forming area of an image formed on the first photosensitive drum.
- FIG. 6 is an explanatory diagram illustrating an image forming area of an image formed on the first and second photosensitive drums.
- FIG. 7 is an explanatory diagram illustrating an image forming area of an image on the first photosensitive drum that is changed before and after detection by the line sensor.
- FIG. 8 is an explanatory diagram illustrating an image forming area of an image on the second photosensitive drum that is changed before and after detection by the line sensor.
- FIG. 9 is a flowchart showing a procedure for changing the image forming area of the electrostatic latent image based on the detection result of the line sensor.
- Fig. 10 is a timing chart showing the timing of writing the electrostatic latent image on each photosensitive drum, the timing of connecting and disconnecting the resist roller clutch, the timing of detecting the line sensor, and the timing of detecting the resist sensor. It is.
- FIG. 11 is a schematic diagram showing a configuration near the first and second photosensitive drums of an image forming apparatus using an electrophotographic method according to the second embodiment of the present invention.
- FIG. 12 is a plan view of the skew state of the recording paper viewed from above the transfer conveyance belt.
- FIG. 13 is a block diagram illustrating a configuration of an image forming system of the image forming apparatus.
- FIG. 14 is an explanatory diagram illustrating an image forming area of an image formed on the first and second photosensitive drums.
- FIG. 15 is an explanatory diagram illustrating an image forming area of an image on the first photosensitive drum that is changed before and after detection by the line sensor.
- FIG. 16 is an explanatory diagram illustrating an image forming area of an image on the second photosensitive drum that is changed before and after detection by the line sensor.
- FIG. 17 is an explanatory diagram illustrating an image forming area of an image on the third and fourth photosensitive drums that is changed before and after the detection by the line sensor.
- FIG. 18 is a flowchart showing a procedure for changing the image forming area of the electrostatic latent image based on the detection result of the line sensor.
- Figure 19 is a timing chart showing the timing of writing the electrostatic latent image on each photosensitive drum, the timing of connecting and disconnecting the resist roller clutch, the timing of detecting the line sensor, and the timing of detecting the resist sensor. It is.
- FIG. 20 is a flowchart showing a procedure for changing the image forming area of the electrostatic latent image based on the detection result of the line sensor by the image forming apparatus using the electrophotographic method according to the third embodiment of the present invention. .
- FIG. 21 is an explanatory diagram illustrating an image forming area of an image on the first photosensitive drum that is changed before and after detection at a second detection point by the line sensor.
- FIG. 22 is a schematic diagram showing a schematic configuration of a mono-claw type digital copying machine using an electrophotographic method according to a fourth embodiment of the present invention.
- FIG. 23 is a plan view of the vicinity of a line sensor according to another modification when viewed from above.
- FIG. 24 is a plan view of the vicinity of a line sensor according to another modification when viewed from above.
- FIG. 25 is an explanatory diagram illustrating the state of recovery of toner cut near the cleaning device according to the conventional example.
- FIG. 1 shows a main part of an electrophotographic image forming apparatus according to a first embodiment of the present invention.
- a transfer and transport belt mechanism 1 is provided in the image forming apparatus X.
- the transfer transport belt mechanism 1 has a drive roller 11 rotatably supported on one side (the left side in FIG. 1) and a rotatable support on the other side (the right side in FIG. 1).
- an endless transfer / transport belt 13 as a sheet carrier that is stretched between the two rollers 11 and 12 and is driven in the direction of the arrow Z shown in FIG.
- the registration rollers 10 and 10 temporarily hold the recording paper P being transported along the paper transport path S. Then, the recording paper P is conveyed in time with the rotation of each of the photoconductor drums 3a to 3d so that the toner images on the respective photoconductor drums 3a to 3d can be transferred onto the recording paper P in a good multiple transfer. It has the function of sending. That is, based on the detection signal output from the resist sensor 10a, the resist rollers 10 and 10 move the leading end of the toner image on each of the photosensitive drums 3a to 3d to the leading end of the printing range on the recording paper P. At the same time, it is set to transport the recording paper P. In this case, the transfer conveyance belt 13 has a thickness of 100 ⁇ ! It is formed endlessly using a film of about 150 ⁇ m.
- a fixing device 2 is provided on the downstream side of the transfer paper belt mechanism 1 in the recording paper P transport direction (the left side in FIG. 1). Fixing is performed on top.
- the fixing device 2 is provided with a heat roller 21 and a pressure roller 22 at the top and bottom, and heats the front and back of the recording paper P conveyed on the transfer belt mechanism 1 (transfer belt 13). The paper is passed through a nip between the heat roller 21 and the pressure roller 22.
- a first image forming station S1, a second image forming station S2, a third image forming station S3, and a fourth image forming station S4 are provided above the transfer / transport belt mechanism 1. Each of them is arranged adjacent to the transfer conveyance belt 13 at predetermined intervals in order from the upstream side of the recording paper conveyance path (the right side in FIG. 1). In this case, the recording paper P on the transfer conveyor belt 13 is transferred to the first image forming station S1, the second image forming station S2, the third image forming station S3, and the fourth image forming station S. Sequentially transported to 4 PC orchid 004/006366
- Each of the image forming stations S1 to S4 has substantially the same configuration, and includes first to fourth photosensitive drums 3a to 3d as image carriers that rotate in the direction of arrow F shown in FIG. ing.
- a charge is applied to each of the photoconductor drums 3a to 3d to form an electrostatic latent image on the outer peripheral surface of each of the photoconductor drums 3a to 3d.
- first to fourth exposure means 8a to 8d are provided above the photosensitive drums 3a to 3d.
- Each of the exposure means 8a to 8d is a writing means, and an image is formed on the surface of each of the charged photosensitive drums 3a to 3d based on image information by light such as an LED or a laser. Write. As a result, an electrostatic latent image is formed on each of the photosensitive drums 3a to 3d.
- a pixel signal corresponding to the black component image of the color original image is input to the first exposure unit 8a of the first image forming station S1 located on the most upstream side in the transport direction of the transfer transport belt 13.
- a pixel signal corresponding to the cyan color component image of the color original image is input to the second exposure means 8b of the next second image forming station S2.
- a pixel signal corresponding to the magenta color component image of the color original image is input to the third exposure unit 8c, and the color is input to the fourth exposure unit 8d of the fourth image forming station S4 located at the most downstream side.
- a pixel signal corresponding to the one-color component image of the original image is input.
- an electrostatic latent image corresponding to the color-converted document image information is formed on the outer peripheral surface of each of the photosensitive drums 3a to 3d.
- the first developing device 5a of the first image forming station S1 contains black toner
- the second developing device 5b of the second image forming station S2 contains cyan toner.
- the third developing device 5c of the third image forming station S3 contains a magenta toner
- the fourth developing device 5d of the fourth image forming station S4 has a yellow color.
- the electrostatic latent image on the outer peripheral surface of each photosensitive drum 3a to 3d is developed into a visible image by the toner of each color, whereby the original image information is converted to the toner of each color. Is to be reproduced as a single image.
- a recording paper suction charger (not shown) is provided between the first image forming station S1 and the transfer conveyance belt 13. This charger for attracting recording paper charges the surface of the transfer conveyance belt 13, and transfers the recording paper P supplied from a paper feed tray 19 provided below the image forming apparatus X to the transfer conveyance belt.
- the recording paper P is conveyed from the first image forming station S1 to the fourth image forming station S4 without being shifted by securely adsorbing the recording paper P on the recording medium P.
- the transfer of the toner image from each of the photosensitive drums 3 a to 3 d to the recording paper P is performed by the transfer rollers 6 a to 6 d which are in contact with the back side of the transfer / conveyance belt 13.
- a high-voltage transfer bias (a high voltage having a polarity (+) opposite to the charge polarity (-) of the toner) is applied to transfer the toner image.
- Each of the transfer rollers 6a to 6d is based on a metal (for example, stainless steel) shaft having a diameter of 8 to 10 mm, and its surface is covered with a conductive elastic material (for example, EPDM, urethane foam, or the like). With this conductive elastic material, a high voltage can be uniformly applied to the recording paper P.
- the transfer rollers 6a to 6d are used as transfer electrodes, but a brush or the like is also used.
- the toner attached to the transfer conveyance belt 13 due to the contact with each of the photoconductor drums 3a to 3d may stain the back surface of the recording paper P. Removed ⁇ Set to be collected.
- a cleaning blade (not shown) is provided to transfer a portion (below the third image forming station S3 and the fourth image forming station S4) where the cleaning blade contacts.
- the transport belt 13 is supported from the back side by a transfer transport belt driven roller 13b. Further, a transfer / conveyance belt driven roller 13 c is provided below the first image forming station S 1, and the transfer / conveyance belt 13 is supported from behind by the transfer / conveyance belt driven roller 13 c. It has become so.
- the paper feed tray 19 is a tray for storing recording paper P used for image formation, and is provided below the image forming unit of the image forming apparatus X. Further, a paper discharge tray 17 provided at the upper part of the image forming apparatus X is a tray for placing the recording paper P on which an image has been formed in a face-down manner.
- the paper output tray 18 provided in the printer is a tray on which recording paper on which an image has been formed is placed face-up.
- an S-shaped paper transport path for sending the recording paper P in the paper feed tray 19 to the output tray 17 via the transfer belt mechanism 1 and the fixing device 2 is provided.
- S is provided.
- a pickup roller 19a, a resist roller 10, a transport direction switching guide 34, and a recording paper P are provided in the paper transport path S from the paper feed tray 19 to the paper output tray 17 and the paper output tray 18.
- a transport mechanism unit 300 such as a transport roller 35 for transport is provided.
- the transport roller 35 is a small roller that facilitates and assists the transport of the recording paper P.
- a plurality of the transport rollers 35 are provided along the paper transport path S.
- the conveyance direction switching guide 34 is rotatably provided on the side cover Xa of the image forming apparatus X.
- the conveyance direction switching guide 34 is provided from the middle of the paper conveyance path S.
- the recording paper P is separated, and the recording paper P is discharged to the discharge tray 18 on the side of the image forming apparatus X.
- the conveyance direction switching guide 34 is converted to the state shown by the solid line, the recording paper P is formed between the fixing device 2, the side cover Xa, and the conveyance direction switching guide 34.
- the paper is discharged to the upper paper discharge tray 17 through the transport section Sa (part of the paper transport path S).
- a line sensor 51 is provided as a detecting means for detecting the edge position (end position) of the recording paper P conveyed toward the recording paper P. As shown in FIG.
- the line sensor 51 is provided below one side (lower side in FIG. 3) of the direction orthogonal to the transport direction of the recording paper P.
- the line sensor 51 is separated from the paper transport path S as shown in FIG.
- the edge position of the recording paper P is detected based on whether or not it is blocked by the paper P.
- the line sensor 51 is located immediately downstream of the registration rollers 10 and 10 in the recording paper conveyance direction. Before the line sensor 51 detects the edge position of the recording paper P, the registration rollers 10 and 10 correct the transport inclination of the recording paper P by the registration rollers 10 and 10, and the recording paper P The positions of the toner images (images) on the photosensitive drums 3a to 3d are adjusted, in which case the irradiation light emitted from the illumination means 52 is directly input to the line sensor 51.
- the line sensor 51 can be arranged close to the recording paper P, and the edge position of the recording paper P can be accurately detected without using lens means. It is also possible.
- a commercially available line image sensor head for a small scanner is used as the in-sensor 51. According to this, the resolution is 200 to 300 dpi, and the number of pixels is 864-: 1 2 1 6. It has a reading range of about 104 mm.
- the maximum size of the recording paper P is A3 (shown by a solid line in Fig. 3), while the minimum size is As a postcard (indicated by the two-dot chain line in Fig.
- the distance L 1 from the detection point R of the edge position of the recording paper P by the line sensor 51 to the transfer point G is the first photosensitive drum of the first image forming station S 1.
- the distance is set to be shorter than the distance L0 from the writing point Q of the electrostatic latent image (image) to the transfer point G by the first exposure means 8a to 3a.
- FIG. 4 is a block diagram illustrating a configuration of the image forming system of the image forming apparatus X.
- the image forming system includes an image processing unit 403 having an image data input unit 401, a memory unit 402, an optical writing unit 404, an operation unit 405, a data storage unit 4 06, an operation unit 407, a line sensor 51, and a resist sensor 10a. Each part of this image forming system is controlled by the control unit 40.
- the image forming system further includes the above-described transport mechanism 300, chargers 4a to 4d, developing devices 5a to 5d, transfer rollers 6a to 6d, and a fixing device 2. .
- the operation unit 405 is provided with a switching switch (not shown) for switching to a borderless image forming mode when a borderless image is formed on the recording paper P.
- a switching switch (not shown) for switching to a borderless image forming mode when a borderless image is formed on the recording paper P.
- an electrostatic latent image larger than the size of the recording paper P whose edge position is detected by the line sensor 51 is formed in the first image forming station S1. 1 Written on photoconductor drum 3a.
- the size of the electrostatic latent image on the first photosensitive drum 3a transferred to the middle of the recording paper P is determined by the detection result of the line sensor 51. (The detection result of the edge position of the recording paper P).
- the electrostatic latent image (toner image) on the first photosensitive drum 3a whose size has been changed, the subsequent image formation on the recording paper P is continuously performed.
- the recording paper P having a width W 0 width in the horizontal direction orthogonal to the recording paper transport direction
- the recording paper P having a width W 0 width in the horizontal direction orthogonal to the recording paper transport direction
- the conveyance inclination of the recording paper P in the paper conveyance path s is corrected by aligning the leading ends with the registration rollers 10 and 10.
- the effective width W1 in the direction orthogonal to the recording paper P conveyance direction is obtained.
- margins W2 and W2 of about 1 mm are added to both sides of the effective width W1, and the width W4 (W4) of the image forming area in the horizontal direction orthogonal to the recording paper conveyance direction is added. l + W 2 X 2).
- the first developing device 5a After writing the electrostatic latent image having the image forming area width W4 in the lateral direction on the first photosensitive drum 3a of the first image forming station S1 by the first exposure means 8a, the first developing device 5a to form a toner image having an image forming area width W4 in the horizontal direction larger than the horizontal width W0 of the recording paper P. At this time, the default value of the horizontal width W 0 of the selected recording paper P and the horizontal image forming area width w of the input electrostatic latent image
- the position and the magnification of the image on the recording paper P are set according to step 4, but may be set automatically or manually by the operation guide of the image forming apparatus X.
- the width W4 of the image forming area in the horizontal direction of the toner image (electrostatic latent image) on the first photosensitive drum 3a of the first image forming station S1 is orthogonal to the initially set recording paper conveyance direction. This is a value that is stored in advance in the data storage unit 406 for each size and type of the recording paper P.
- W5 is a margin in the transport direction (longitudinal direction) including a start variation of the recording paper P by the registration rollers 10 and 10, and a margin.
- the storage unit 406 stores the recording paper P for each size and type.
- W 7 is a default value of the length of the recording paper P in the conveyance direction of the recording paper, and the default value W 7 of the length of the recording paper P is also stored in advance in the data storage unit 406 for each size and type of the recording paper P It is remembered. Then, based on the margin W5 in the recording paper transport direction and the default length W7 of the recording paper P, the toner image (electrostatic latent) on the first photosensitive drum 3a of the first image forming station S1 is obtained.
- the image forming area length W 9 (W 7 + W 5 X 2) in the vertical direction parallel to the recording paper transport direction of the image) is determined.
- the electrostatic latent image written on the first photosensitive drum 3a by the first exposure means 8a (developed by the first developing device 5a)
- the width W4 of the image forming area in the horizontal direction of the toner image to be formed is set to the electrostatic latent based on the detection result of the edge position of the recording paper P by the line sensor 51 during the image formation on the first photosensitive drum 3a.
- the width of the image forming area in the horizontal direction of the image is changed to W6, and the electrostatic latent image is continuously written on the first photosensitive drum 3a by the first exposure means 8a.
- an electrostatic latent image (the first developing device 5a) written on the first photosensitive drum 3a by the first exposure unit 8a is used. Is changed so that the width of the image forming area in the horizontal direction of the toner image to be developed is reduced from W4 to W6.
- the writing of the electrostatic latent image (image) by 8d is performed after the line sensor 51 detects the edge position of the recording paper P, and as shown in FIG. 8, on the photosensitive drums 3b to 3d.
- the width W 61 of the image forming area in the horizontal direction and the length W 91 of the image forming area in the vertical direction are determined by the exposure means 8 b to 8 d based on the detection result of the edge position of the recording paper P by the line sensor 51. It has been changed and set before writing the latent image.
- the default value W71 of the length in the vertical direction of the toner image (electrostatic latent image) on the photosensitive drums 3b to 3d of the second to fourth image forming stations S2 to S4 Is a value calculated from the detection result of the front end and the rear end of the recording paper P by the line sensor 51, and the margin W is provided on both front and rear sides of the predetermined value W71 of the vertical length. 8 (for example, about l mm), and the length W 9 1 (W 7 1) of the vertical image forming area of the electrostatic latent image written on the photosensitive drums 3 b to 3 d. + W 8 X 2).
- the default value WO 1 of the horizontal length of the toner image (electrostatic latent image) on the photosensitive drums 3 b to 3 d of the second to fourth image forming stations S 2 to S 4 is This is a value calculated from the detection results of the leading edge and the trailing edge of the recording paper P by the sensor 51, and the margin value W3 is added to each of the left and right sides of the default value WO1 of the lateral length.
- the width W61 (WO1 + W3X2) of the image forming area in the horizontal direction of the electrostatic latent image written on the photosensitive drums 3b to 3d is determined.
- step ST1 of the flowchart in FIG. 9 after the image forming operation is started by pressing the start button of the operation unit 405, it is determined in step ST2 whether the mode has been switched to the borderless image forming mode by the switching switch. Is determined. If the determination in step ST2 is NO, in which the mode has not been switched to the borderless image forming mode, the process proceeds to step ST12, in which a normal bordered image is formed. Go to 0.
- step ST3 the data is stored in the data storage unit 406 from the information on the size of the recording paper P to be used.
- the margin W5 of the electrostatic latent image including the start variation and margin of the paper P, and the default value W7 of the electrostatic latent image in the vertical direction of the recording paper transport direction are set.
- step ST4 the writing of the electrostatic latent image is started on the first photosensitive drum 3a of the first image forming station S1 by the first exposing means 8a with the image forming area width W4 in the horizontal direction. I do.
- step ST5 the line sensor 51 detects a horizontal edge position (one of left and right side edge positions) parallel to the transport direction of the recording paper P, and From the detection result, an actual lateral width WO1 in the lateral direction orthogonal to the transport direction of the recording paper P is obtained. Then, in step ST6, the images (electrostatic latent image and toner image) on the first photosensitive drum 3a in which the allowance W3 is given to both the left and right sides of the actual width W01 obtained in step ST5 above, respectively.
- the width W 6 of the image forming area in the horizontal direction is calculated by the calculation unit 4 07, and the first exposure means 8 a is placed on the first photosensitive drum 3 a before the edge position of the recording paper P is detected by the line sensor 51.
- the width of the image forming area in the horizontal direction of the electrostatic latent image is changed to W6 based on the detection result of the edge position of the recording paper P by the sensor 51.
- step ST7 the photosensitive drums 3b to 3d are transferred to the second to fourth image forming stations S2 to S4 downstream of the first image forming station S1 in the recording paper conveyance direction.
- Writing of the electrostatic latent image (image) by the exposure means 8b to 8d is performed based on the detection result of the edge position of the recording paper P by the line sensor 51, as shown in FIG.
- the width W61 of the image forming area in the horizontal direction on 3b to 3d and the margin W8 in the vertical direction are set, and the electrostatic latent by the exposure means 8b to 8d on the photosensitive drums 3b to 3d. Start writing the image.
- step ST8 a default value of the vertical length of the electrostatic latent image (toner image) on the photosensitive drums 3b to 3d of the second to fourth image forming stations S2 to S4 is set.
- W71 is calculated from the detection results of the leading edge and the trailing edge of the recording paper P by the line sensor 51, and a margin W8 (e.g., l mm), and the length of the vertical image forming area W91 (W71 + W) of the electrostatic latent image written on the second photosensitive drum 3b of the second image forming station S2 is added.
- 8 X 2) is determined.
- step ST9 the horizontal image forming area width W61 and the vertical image forming area length W on the second photosensitive drum 3b set in the second image forming station S2 are set.
- step ST9 Write an electrostatic latent image on the photosensitive drums 3c and 3d of the third and fourth image forming stations S3 and S4 by the exposure means 8c and 8d as shown in 1. 2004/006366
- step ST10 the electrostatic latent images written on the photosensitive drums 3a to 3d of the image forming stations S1 to S4 are developed into toner images by the developing devices 5a to 5d, After the images are sequentially transferred to the recording paper P on the transfer conveyance belt 13, in step ST 11, the image of the recording paper P after the above-described transfer is fixed by the fixing device and discharged onto the discharge trays 17 and 18. .
- the timing of writing the electrostatic latent image on the photosensitive drums 3a to 3d of each of the image forming stations S1 to S4, and the registration roller clutches for disconnecting and connecting the driving force to the registration rollers 10 and 10 The connection / disconnection timing, the detection timing of the edge position of the recording paper P by the line sensor 51, and the detection timing by the registration sensor 10a will be described based on the timing chart of FIG.
- the writing of the electrostatic latent image on the first photosensitive drum 3a of the first image forming station S1 is performed based on the detection start (ON) of the registration sensor 10a. T Starts almost simultaneously with the connection (ON) of the registration roller clutch 2 seconds later.
- the width W4 of the image forming area in the horizontal direction of the electrostatic latent image written by the exposure means 8a is the edge of the recording paper P by the line sensor 51 during the image formation on the first photosensitive drum 3a.
- the width is changed to the width W6 of the image forming area in the horizontal direction of the electrostatic latent image based on the position detection result.
- the width W 61 of the image forming area in the horizontal direction and the length W 91 of the image forming area in the vertical direction on the photosensitive drums 3 b to 3 d of the image forming stations S 2 to S 4 are the line sensors 5 1 Is set beforehand before writing the electrostatic latent image by the exposure means 8b to 8d based on the detection result of the edge position of the recording paper P by the above.
- the dashed line of the reading timing of the line sensor 51 indicates the connection (ON) of the registration roller clutch 1 second after T with respect to the detection start (ON) of the registration sensor 10a and the line sensor 51 at the same time. This indicates that reading has started.
- the solid line of the reading timing of the line sensor 51 indicates the time when the recording paper P conveyed on the transfer conveyance belt 13 is actually read by the line sensor 51.
- the edge position of the trailing edge of the recording paper P is detected (T5 seconds after the edge position of the leading edge is detected by the line sensor)
- the connection of the registration roller clutch is disconnected (OFF).
- the detection of the edge position of the recording paper P by the line sensor 51 is performed continuously to the rear end of the recording paper P on the transfer conveyance belt 13.
- the line sensor 51 may detect only necessary parts. In other words, according to the size of the recording paper selected, the edge position parallel to the leading edge of the recording paper and the transport direction can be determined by detecting the leading edge and the trailing edge of the recording paper at least twice.
- Both end positions) and the rear end passage timing may be detected.
- Color registration ratio (color matching) correction control is performed so that an excellent image quality can be obtained. That is, the data storage unit 406 of the image forming apparatus X stores the image formed on the reference photosensitive drum (for example, the first photosensitive drum 3a on the most upstream side) on the other photosensitive drums 3b to 3d. Data for detecting the position (timing) is stored in advance.
- the positions of the images formed on the respective photoconductor drums 3b to 3d are corrected, and the images formed on the respective photoconductor drums 3a to 3d are correctly overlapped and color-shifted without shifting. It is controlled so that no deviation occurs. Therefore, in the first embodiment, when the mode is switched to the borderless image forming mode by the switching switch of the operation unit 405, the electrostatic latent image having the larger size than the size of the recording paper P is formed in the first image forming mode. Writing can be started on the first photosensitive drum 3a of the station S1.
- the size of the electrostatic latent image on the first photosensitive drum 3a transferred to the middle of the subsequent recording paper P is determined by the line sensor 5 It is changed based on the detection result (detection result of edge position of recording paper P) by step 1.
- the subsequent image formation on the recording paper P is continuously performed. Specifically, when the recording paper P having the width W0 is conveyed and the leading edge is corrected by the registration rollers 10 and 10, the correction deviation of the recording paper P due to the correction is anticipated as shown in FIG. To obtain the effective width W1 of the recording paper P. As shown in FIG.
- a margin W2 and W2 of about 1 mm are added to both sides of the effective width W1 and the width W4 (Wl + W2X 2) and start writing the electrostatic latent image having the width W4 in the horizontal direction on the first photosensitive drum 3a of the first image forming station S1 by the first exposure means 8a.
- the actual width W0 of the recording paper P is obtained from the detection result of the edge position of the recording paper P by the line sensor 51, as shown in FIG. 7, both the left and right sides of the obtained actual width W0 are obtained as shown in FIG.
- the calculation unit 407 calculates the width W6 of the image forming area in the horizontal direction of the image (the electrostatic latent image and the toner image) on the first photosensitive drum 3a to which the allowance W3 is given.
- the electrostatic latent image (developed by the first developing device 5a) written on the first photosensitive drum 3a by the first exposure device 8a before the line sensor 51 detects the edge position of the recording paper P is detected.
- the width W 4 of the image forming area in the horizontal direction of the toner image is determined based on the detection result of the edge position of the recording paper P by the line sensor 51 during the image formation on the first photosensitive drum 3 a.
- the width of the image forming area in the horizontal direction of the electrostatic latent image is changed to W6, and the electrostatic latent image is continuously written on the first photosensitive drum 3a by the first exposure means 8a. That is, before and after the edge position of the recording paper P is detected by the line sensor 51, the electrostatic latent image (the first developing device) written on the first photosensitive drum 3a by the first exposure means 8a 5 by a
- the width of the image forming area in the horizontal direction of the toner image to be developed is changed so as to decrease. Therefore, even before the edge position of the recording paper P is detected before the detection by the line sensor 51, the toner image (electrostatic force) on the first photosensitive drum 3a that is larger than the size of the recording paper P is detected.
- the latent image With the latent image, it is possible to transfer a good image onto the recording paper P without causing image loss due to the conveyance deviation of the recording paper P.
- the first photosensitive drum 3 is detected based on the detection result of the edge position of the recording paper P.
- the size of the toner image on a is changed to the size according to the edge position of the recording paper P.
- the amount of toner collected by the cleaning device 7a without being transferred to the recording paper P is reduced as much as possible, and waste of toner can be suppressed, and economical toner consumption can be achieved.
- the cycle until the collected toner is full can be extended.
- the cleaning device 7a in which the container for collecting the collected toner is integrated the collected toner is prevented from partially accumulating in the container, and the collected toner is partially leaked. It is possible to prevent the cleaning failure due to this.
- the line sensor 51 detects the edge position of the recording paper P
- an electrostatic latent image is written on the first photosensitive drum 3a by the first exposure means 8a, so that the line sensor 51 is transferred to the transfer point. It will be possible to set up close to G.
- the transport distance L1 of the recording paper P from the detection point R of the edge position of the recording paper P by the line sensor 51 to the transfer point G becomes shorter in the transport direction of the recording paper P
- the image forming apparatus X becomes compact.
- the time required for image formation can be shortened.
- the line sensor 51 is located immediately downstream of the registration rollers 10 and 10 so that the conveyance inclination of the recording paper P is corrected before the line sensor 51 detects the edge position of the recording paper P. Therefore, the oblique conveyance of the recording paper P conveyed toward the transfer point G is corrected by the registration rollers 10 and 10. Therefore, the edge position of the recording paper P is detected by the line sensor 51 in a state where the recording paper P is transported almost straight, and high precision is obtained.
- the edge position of the recording paper P is detected in degrees, and the marginal image on the first photosensitive drum 3a formed before the line sensor 51 detects the edge position of the recording paper P
- the size also becomes as small as possible. This is very advantageous in reducing the amount of waste toner collected without being transferred to the recording paper P.
- the distance L1 from the detection point R by the line sensor 51 to the transfer point G is longer than the distance L0 from the writing point Q of the electrostatic latent image to the first photosensitive drum 3a to the transfer point G. Since the setting is made shorter, the edge position of the recording paper P can be detected by the line sensor 51 at an early stage. The size of the electrostatic latent image on the first photosensitive drum 3a is quickly changed based on the detection result of the edge position of the recording paper P after the detection by the line sensor 51. The amount of waste toner collected without being transferred to P can be more effectively reduced.
- the first photosensitive drum 3a of the first image forming station S1 which is located on the most upstream side in the transport direction of the recording paper P, receives the image after the edge position of the recording paper P is detected by the line sensor 51.
- the size of the electrostatic latent image written on the first photosensitive drum 3a by the first exposure means 8a is changed.
- exposure means 8 is provided on the respective photosensitive drums 3b to 3d.
- the data storage unit 406 of the image forming apparatus X stores image forming positions on the other photosensitive drums 3 b to 3 d with respect to the reference photosensitive drum (for example, the first photosensitive drum 3 a on the most upstream side).
- the data to correct (timing) is stored in advance.
- the position of the image formed on each of the photoconductor drums 3 b to 3 d is corrected based on the data, and the images formed on each of the photoconductor drums 3 a to 3 d are correctly overlapped without displacement and color shift. Is controlled so as not to occur.
- the range of the image formed on each of the photoconductor drums 3a to 3d also depends on the data of the transport timing of the recording paper P obtained by the line sensor 51 5the transport position and the data for the color registration.
- the position of each of the photosensitive drums 3a to 3d is determined by the determination based on the correction data, and the electrostatic latent images by the exposure means 8b to 8d on the photosensitive drums 3b to 3d It is possible to set a small margin for forming an image without being influenced by the positional deviation of writing of the image, the conveyance inclination of the transfer conveyance belt 13 and the like.
- the position and magnification of the image on the recording paper P are set by the default value of the width W0 of the selected recording paper P and the width W4 of the image forming area in the horizontal direction of the input electrostatic latent image. If the position or magnification is changed when changing the range in which the electrostatic latent image is written on the first photosensitive drum 3a during the image formation on the recording paper P, the continuity of the image may be lost or the image may be distorted. However, if the position and the magnification of the image are set based on predetermined data, good image formation can be performed.
- black toner is applied to the first image forming device 5a of the first image forming station S1
- cyan toner is applied to the second developing device 5b of the second image forming station S2.
- the magenta toner is stored in the third image forming device 5c of the third image forming station S3, and the yellow toner is stored in the fourth developing device 5d of the fourth image forming station S4.
- Black toner, cyan toner, magenta toner and yellow toner may be stored in the developing device of each image forming station in any order.
- the line sensor 51 detects only the edge position of the recording paper P. This is changed so that the edge position of the recording paper P is detected at two points in the recording paper transport direction, and the skew state of the recording paper P can be detected.
- This will be described below as a second embodiment.
- the same components as those in the first embodiment are denoted by the same reference numerals, and the description will be made mainly on the differences.
- FIG. 11 is a schematic diagram showing a configuration near the first and second photosensitive drums in the second embodiment.
- FIG. 12 is a plan view illustrating the skew state of the recording paper viewed from above the transfer carrying belt.
- the line sensor 51 detects the edge position of the recording paper P conveyed toward the transfer point G at two positions in the recording paper conveyance direction (including the first detection point R1 of the edge position of the recording paper P). To detect. As a result, as shown in FIG. 12, the recording is performed from the inclination angle ⁇ of the center line o parallel to one of the left and right edges of the recording paper P (side parallel to the transport direction) with respect to the parallel line h parallel to the recording paper transport direction. The skew status of paper P is detected.
- the inclination angle ⁇ of the recording paper P is determined by the first and second detection intervals (time difference) by the line sensor 51 and the first and second detection results, that is, the left and right edges of the recording paper P It is calculated by the controller 40a (see FIG. 13) based on the reading result (position) and the transport speed of the recording paper P.
- the distance L 1 from the first detection point R 1 of the edge position of the recording paper P by the line sensor 51 to the transfer point G is determined by the first image forming station S 1.
- the distance from the writing point Q of the electrostatic latent image (image) on the first photosensitive drum 3a by the first exposure means 8a to the transfer point G is set to be shorter than the distance L0.
- FIG. 13 is a block diagram illustrating a configuration of an image forming system of the image forming apparatus X according to the second embodiment. Note that the only difference from FIG. 4 of the first embodiment is the control unit 40a.
- the line sensor 51 detects the edge position and the skew state of the recording paper P
- the electrostatic latent image on the first photosensitive drum 3 a transferred to the middle of the recording paper P thereafter is detected.
- the size is changed based on the detection result of the edge position of the recording paper P and the skew state by the line sensor 51.
- the electrostatic latent image (toner image) on the first photosensitive drum 3a whose size has been changed, the subsequent image formation on the recording paper P is continuously performed.
- a recording sheet P having a width W 0 width in the horizontal direction orthogonal to the recording sheet conveying direction
- the registration rollers 10 and 10 are moved. Is reached, the conveyance inclination of the recording paper P in the paper conveyance path S is corrected by aligning the leading end with the registration rollers 10 and 10.
- the correction deviation of the recording paper P due to the correction the deviation between the two-dot chain line and the dashed line shown in FIG.
- the effective width W 1 in the direction orthogonal to the transport direction of the recording paper P (registration roller 1) Includes the shift of the transport position when the recording paper P conveyed to 0, 10 is corrected, and also considers the skew of the recording paper P, which could not be corrected completely by the registration rollers 10 and 10. That is).
- the margins W2 and W2 of about 1 mm are added to the left and right sides of the effective width W1, respectively, and the width of the image forming area W4 (Wl + W) in the horizontal direction orthogonal to the recording paper conveyance direction is added. 2 X 2) is determined.
- This lateral latent image forming area width W4 of the electrostatic latent image is written on the first photosensitive drum 3a of the first image forming station S1 by the first exposure means 8a, and the first developing device 5a , A toner image having a width W4 of the image forming area in the horizontal direction larger than the width W0 of the recording paper P is started.
- the position and magnification of the image on the recording paper P are set by the default value of the width W 0 of the selected recording paper P and the width W 4 of the horizontal image forming area of the input electrostatic latent image.
- a configuration in which the setting is performed automatically or manually by operation guidance of the image forming apparatus X may be adopted.
- the width W4 of the image forming area in the horizontal direction of the toner image (electrostatic latent image) on the first photosensitive drum 3a of the first image forming station S1 is orthogonal to the initially set recording paper conveyance direction. This is a value that is stored in advance in the data storage unit 406 for each size and type of the recording paper P.
- Figure 1 As shown in Fig. 5, W5 is a margin before and after in the transport direction (longitudinal direction) including a start variation and a margin of the recording paper P due to the registration rollers 10 and 10, and the margin W5 is also determined in advance.
- the data storage unit 406 stores the size and type of the recording paper P.
- W 7 is a default value of the length of the recording paper P in the transport direction
- the default value W 7 of the length of the recording paper P is also stored in the data storage section 406 in advance.
- W71 is a default value obtained by replacing the default value W7 of the length of the recording paper P with a component having a length parallel to the recording paper transport direction. Then, the margin W5 in the recording paper transport direction and the default value W71 of the length parallel to the transport direction of the recording paper P are set on the first photosensitive drum 3a of the first image forming station S1.
- the image forming area length W 9 (W 71 + W 5 X 2) of the toner image (electrostatic latent image) in the vertical direction, which is parallel to the recording paper transport direction, is determined. These values are calculated from predetermined values, but the margin W5 in the recording paper transport direction and the default value W7 of the length of the recording paper P are stored in the data storage unit 406 for recording. The size may be stored in advance for each size / type of paper P.
- an actual horizontal width W01 orthogonal to the transport direction of the recording paper P is obtained.
- An image forming area width W 6 (W 0 1) of the image (electrostatic latent image and toner image) on the first photosensitive drum 3 a provided with a margin W 3 on each of the left and right sides of the actual width WO 1. + W 3 X 2) is calculated by the arithmetic unit 407.
- the line sensor 51 detects the edge position of the recording sheet P at the first detection point R1.
- the width W4 of the image forming area in the horizontal direction of the toner image developed by the developing device 5a is determined by the first detection point R1 by the line sensor 51 during the image formation on the first photosensitive drum 3a.
- the width of the image forming area in the horizontal direction of the electrostatic latent image is changed to W6 based on the detection result of the edge position of the recording paper P, and the electrostatic latent image is exposed on the first photosensitive drum 3a by the first exposure means 8 Write continuously with a.
- the controller 40a calculates the inclination angle 0 of the recording paper P based on the detection interval (a predetermined time difference) from the point R2 and the transport speed of the recording paper P, and calculates the recording paper P from the inclination angle ⁇ . Is detected.
- the line sensor 5 1 Before the detection of the edge position of the recording paper P at the second detection point R2 (before detecting the skew state of the recording paper P), the data is written on the first photosensitive drum 3a by the first exposure means 8a.
- the margin W3 in the lateral direction of the electrostatic latent image (toner image developed by the first developing device 5a) is reduced to a margin W3 1 (for example, about l mm) based on the detection result of the skew state.
- the writing of the image (image) is performed after the line sensor 51 detects the edge position of the recording paper P at the second detection point R2, that is, after the skew state of the recording paper P is detected.
- the horizontal image forming area width W61 on the second photosensitive drum 3b and the vertical image forming area The area length W 91 is determined by the second exposure means based on the detection result of the edge position and the skew state of the recording paper P at the first and second detection points R 1 and R 2 by the line sensor 51.
- the length W 91 of the image forming area in the vertical direction on the second photosensitive drum 3 b is determined by the recording paper at the first and second detection points R 1 and R 2 of the recording paper P by the line sensor 51.
- the default value of the length in the vertical direction parallel to the transport direction of the recording paper P obtained from the detection result of the edge position and the skew of P
- the width W 61 of the image forming area in the horizontal direction on the second photosensitive drum 3 b is equal to the toner image on the second photosensitive drum 3 b of the second image forming station S 2.
- Electrostatic latent image is determined by adding a margin W31 to each of the left and right sides of the actual horizontal width WO1 of the (electrostatic latent image).
- R2 The default value of the length in the vertical direction parallel to the transport direction of the recording paper P obtained from the edge position of the recording paper P and the detection result of the skew state in R2 It is determined by adding a margin W8 (for example, about l mm) to the front and rear sides on the line o).
- a margin W8 for example, about l mm
- the width W 61 of the image forming area in the horizontal direction on the third and fourth photosensitive drums 3 c and 3 d is obtained by adding a margin W 31 to each of the left and right sides of the actual width WO 1.
- step ST101 of the flowchart of FIG. 18 the image forming operation is started by pressing the start button of the operation unit 405, and in step ST102, the borderless image forming mode is set by the switching switch. It is determined whether or not it has been switched to. If the determination in step ST102 is NO in which the mode has not been switched to the borderless image forming mode, the process proceeds to step ST114, in which a normal bordered image is formed, and then a step described later is performed. Proceed to ST 1 1 2.
- Each process in steps ST103 and 104 is the same as each process in steps ST3 and ST4 in FIG.
- step ST105 the line sensor 51 detects a lateral edge position (one of the left and right side edge positions) parallel to the transport direction of the recording paper P at the first detection point R1, and From the detection result, the actual lateral width WO1 in the lateral direction orthogonal to the transport direction of the recording paper P is obtained.
- step ST106 the image on the first photosensitive drum 3a (the electrostatic latent image) with the allowance W3 given to the left and right sides of the actual width WO1 obtained in step ST105 above, respectively.
- the calculation unit 407 calculates the width W6 of the image forming area in the horizontal direction of the recording medium P and the toner image on the first photosensitive drum 3a before the line sensor 51 detects the wedge position of the recording paper P.
- the width W4 of the image forming area in the horizontal direction of the electrostatic latent image (the toner image developed by the first developing device 5a) written by the exposure unit 8a is set on the first photosensitive drum 3a. Based on the detection result of the edge position of the recording paper P at the first detection point R1 by the line sensor 51 during image formation, the width of the electrostatic latent image is changed to the image forming area width W6 in the horizontal direction.
- step ST107 the line sensor 51 detects the horizontal edge position (left side) parallel to the transport direction of the recording paper P at the second detection point R2. (The right side position).
- step ST108 the detection interval (time difference) of the first and second detection points Rl and R2 by the line sensor 51 and the respective Based on the detection results (detection results of the edge position) at the detection points Rl and R2 and the transport speed of the recording paper P, the inclination angle 0 of the recording paper P is calculated to detect the skew state of the recording paper P. I do.
- the margin W3 in the lateral direction of the electrostatic latent image is changed to a smaller margin W31, and the image forming area in the lateral direction is adjusted in the horizontal direction (main scanning direction) according to the inclination angle ⁇ of the recording paper P.
- the electrostatic latent image is continuously written on the first photosensitive drum 3a by the first exposure means 8a.
- step ST109 the photosensitive drums 3b to 3d at the second to fourth image forming stations S2 to S4 downstream of the first image forming station S1 in the recording paper transport direction are used.
- the width W61 (see Fig. 16) and the margin W51 (see Fig. 16) in the horizontal direction of the electrostatic latent image (image) by the exposure means 8b-8d Set based on the detection result of the edge position and the skew state of the recording paper P by the sensor 51, and write the electrostatic latent image on the second photosensitive drum 3b by the second exposure means 8b.
- step ST110 the length of the electrostatic latent image (toner image) on the photosensitive drums 3b to 3d of the second to fourth image forming stations S2 to S4 in the vertical direction is determined.
- the value W71 is calculated from the detection result of the edge position and the skew state of the recording paper P by the line sensor 51.
- the writing of the electrostatic latent image on the second photosensitive drum 3b of the second image forming station S2 is continuously performed.
- the image forming area length W92 (W71 + W8X2) in the vertical direction of the image is determined.
- steps ST 1 1 1 the third and fourth image shapes Writing of the electrostatic latent image on the photosensitive drums 3c, 3d of the forming stations S3, S4 is started by the exposure means 8c, 8d.
- steps ST112, 113 are the same as the respective processes in steps ST110, 11 in FIG.
- the timing of writing the electrostatic latent images on the photosensitive drums 3a to 3d of the image forming stations S1 to S4, the registration roller clutch for connecting and disconnecting the driving force to the registration rollers 10 and 10 are described.
- the timing of connection and disconnection, the timing of detecting the edge position of the recording paper P by the line sensor 51, and the timing of detection by the registration sensor 10a will be described based on the timing chart of FIG.
- the writing of the electrostatic latent image on the first photosensitive drum 3a of the first image forming station S1 is performed when the registration sensor 10a starts detection (ON).
- the reference is started almost simultaneously with the connection (ON) of the registration roller clutch 2 seconds after the start of T, and from the start of the writing of the electrostatic latent image on the first photosensitive drum 3a of the first image forming station S1, T Four seconds later, that is, after the line sensor 51 detects the edge position (the left or right side edge position) of the recording paper P at the first detection point R 1 (T 3 seconds from the start of detection of the registration sensor 10a) Later, the horizontal image formation of the electrostatic latent image written by the first exposure means 8a on the first photosensitive drum 3a before the detection of the edge position of the recording paper P by the line sensor 51 is performed.
- the area width W4 is in the middle of forming an image on the first photosensitive drum 3a.
- -Sensor 5 1 according to change in the image forming region width W 6 of the lateral electrostatic latent image that is based on the detection result of the edge position of the recording sheet P.
- the edge position of the paper P (the left or right side edge position) is detected.
- the detection intervals (time difference) of the first and second detection points Rl and R2 by the line sensor 51 and the detection results at each of the detection points Rl and R2 (the edge position reading results) And calculates the inclination angle ⁇ of the recording paper P based on the transport speed of the recording paper P, and detects the skew state of the recording paper P. I am trying to do it.
- the width W 61 of the horizontal image forming area and the length W 91 of the vertical image forming area on the photosensitive drums 3 b to 3 d of the second to fourth image forming stations S 2 to S 4, W92 is set after being changed in advance before writing the electrostatic latent image by the exposure means 8b to 8d based on the detection result of the edge position of the recording paper P by the line sensor 51.
- the color registration correction control is also performed. That is, the data storage unit 406 of the image forming apparatus X stores the reference photosensitive drum (for example, the first photosensitive drum 3a on the most upstream side) to the other photosensitive drums 3b to 3d. Data for correcting the image forming position (timing) is stored in advance. Then, based on the data and the detection results of the edge position and the skew state of the recording paper P at the first and second detection points R 1 and R 2 by the line sensor 51, the respective photosensitive drums are detected. The positions of the images formed on 3b to 3d and the image forming area are corrected, and the images formed on each of the photoconductor drums 3a to 3d are controlled so that they do not overlap with each other without color misregistration. I have.
- the electrostatic latent image having a size larger than the size of the recording paper P is transferred to the first image forming station.
- Writing can be started on the first photosensitive drum 3a of S1.
- the edge position of the recording paper P at the first detection point R1 is detected by the line sensor 51, the subsequent recording paper P
- the size of the electrostatic latent image on the first photosensitive drum 3a transferred to the surface is determined by the detection result of the line sensor 51 (the detection result of the edge position of the recording paper P at the first detection point R1).
- the line sensor 51 detects the edge position of the recording paper P at the second detection point R2
- the inclination angle ⁇ of the recording paper P is calculated based on the detection result
- the inclination angle ⁇ of the recording paper P is calculated.
- the skew state is detected, and while the image forming area in the horizontal direction of the electrostatic latent image is changed, control is performed so as to shift in the horizontal direction (main scanning direction) in accordance with the inclination angle 0 of the recording paper P.
- the subsequent image formation on the recording paper P is continuously performed.
- the recording paper P having the width WO is conveyed and the leading end is corrected by the registration rollers 10 and 10, the recording paper P is corrected by the correction as shown in FIG. 5 and FIG.
- the effective width W1 of the recording paper P is obtained in anticipation of the correction deviation.
- the width W4 (Wl + W2X2) of the image forming area in the horizontal direction of the recording paper is determined by adding margins W2 and W2 of about 1 mm to both sides of the effective width W1.
- the writing of the electrostatic latent image having the width W4 of the image forming area in the horizontal direction onto the first photosensitive drum 3a of the first image forming station S1 is started by the first exposure means 8a.
- the calculation unit 407 calculates the width W 6 of the image forming area in the horizontal direction of the image (the electrostatic latent image and the toner image) on the first photosensitive drum 3 a given the allowance W 3.
- the electrostatic latent image written by the first exposure means 8a on the first photosensitive drum 3a before the line sensor 51 detects the edge position of the recording paper P at the first detection point R1.
- the width W4 of the image forming area in the horizontal direction (the toner image developed by the first developing device 5a) is set to the first detection point by the line sensor 51 during the image formation on the first photosensitive drum 3a.
- the width of the image forming area in the horizontal direction of the electrostatic latent image is changed to W6 based on the detection result of the edge position of the recording paper P in R1. Further, when the edge position of the recording paper P at the second detection point R 2 is detected by the line sensor 51, the detection interval of the first and second detection points R l and R 2 by the line sensor 51 ( Time difference) and each detection point PC leak 004/006366
- the electrostatic latent written on the first photosensitive drum 3a by the first exposure means 8a is performed before and after the edge position of the recording paper P is detected by the line sensor 51 and the skew state.
- the width of the image forming area of the image (the toner image developed by the first developing device 5a) in the horizontal direction is changed to be reduced. Therefore, before the edge position and the skew state of the recording paper P are detected by the line sensor 51, even if the edge position and the skew state of the recording paper P have not been detected, the size is smaller than the size of the recording paper P.
- the single toner image (electrostatic latent image) on the large first photosensitive drum 3a enables a good image to be transferred onto the recording paper P without causing the image to be lost due to the skew of the recording paper P.
- the edge position and the skew state of the recording paper P may not be determined in time for the determination of the image size on the first photosensitive drum 3a. Based on the detection result of one state, the size of the toner image on the first photosensitive drum 3a is changed to a size in accordance with the edge position of the recording paper P.
- the amount of toner collected by the cleaning device 7a without being transferred to the recording paper P is reduced as much as possible, and it is possible to suppress waste of toner and economically consume toner.
- the cycle until the collected toner is full can be extended.
- the cleaning device 7a in which the container for collecting the collected toner is integrated the collected toner is prevented from partially accumulating in the container, and the collected toner is partially leaked. It is possible to prevent the cleaning failure due to the cutting.
- the line sensor 51 detects the edge position of the recording paper P and the skew state, an electrostatic latent image is written on the first photosensitive drum 3a by the first exposure means 8a.
- Move the line sensor 51 to the transfer point G It can be provided.
- the line sensor 51 detects the edge position of the recording paper P from the detection point Rl (R2) to the transfer point G.
- the transport distance L1 of the recording paper P is shorter than the recording paper P;
- the size of the device X can be reduced, and the time required for image formation can be shortened.
- the line sensor 51 is provided immediately downstream of the registration rollers 10 and 10 in the recording paper conveyance direction, the diagonal conveyance of the recording paper P conveyed toward the transfer point G is performed by the registration rollers 1.
- the edge position of the recording sheet P is detected by the line sensor 51 in a state where the recording sheet P is almost straightened, and the edge position of the recording sheet P is detected with high accuracy.
- the size of the image having a margin on the first photosensitive drum 3a formed before the detection of the edge position and the skew state of the recording paper P by 51 is also reduced as much as possible. This is very advantageous in reducing the amount of waste toner collected without being transferred to the recording paper P.
- the distance L 1 from the detection point R 1 (R 2) of the line sensor 51 to the transfer point G is determined from the transfer point G of the electrostatic latent image writing point Q to the first photosensitive drum 3 a. Is set to be shorter than the distance L0 to the line sensor 51, the line sensor 51 can detect the edge position and the skew state of the recording paper P at an early stage. The size of the electrostatic latent image on the first photosensitive drum 3a is quickly changed based on the detection result of the edge position and the skew state of the recording paper P after the detection by the line sensor 51. Thus, the amount of waste toner collected without being transferred to the recording paper P can be reduced more effectively.
- the first photosensitive drum 3a of the first image forming station S1 which is located on the most upstream side in the transport direction of the recording paper P, detects the edge position and the skew state of the recording paper P by the line sensor 51. During the subsequent image formation, the size of the electrostatic latent image written on the first photosensitive drum 3a by the first exposure means 8a is changed.
- the photosensitive drums 3b to 3d of the second to fourth image forming stations S2 to S4 which are further downstream in the transport direction, Before writing the electrostatic latent image on the body drums 3b to 3d by the exposure means 8b to 8d, the size based on the detection result of the edge position and the skew state of the recording paper P by the line sensor 51 An electrostatic latent image of a size as small as possible is written. This effectively reduces the amount of waste toner that is not transferred to the recording paper P and collected in the cleaning devices 7 b to 7 d of the second to fourth image forming stations S 2 to S 4. However, the cycle until the containers of the cleaning devices 7b to 7d are full can be drastically lengthened.
- the data storage unit 406 of the image forming apparatus X stores image forming positions on the other photosensitive drums 3 b to 3 d with respect to the reference photosensitive drum (for example, the first photosensitive drum 3 a on the most upstream side). (Timing) is stored in advance, and the data and the detection result of the edge position and the skew state of the recording paper P at the first and second detection points R 1 and R 2 by the line sensor 51 are stored. The position of the image formed on each of the photoconductor drums 3b to 3d is corrected based on this, so that the images formed on each of the photoconductor drums 3a to 3d are correctly overlapped without misalignment and color misregistration does not occur. Is controlled.
- the positional deviation of the respective photosensitive drums 3a to 3d the positional deviation of the writing of the electrostatic latent image by the exposure means 8b to 8d on the photosensitive drums 3b to 3d, and the transfer.
- the conveyance belt 13 has a conveyance inclination, etc., after the line sensor 51 detects the edge position and the skew state of the recording paper P, it is conveyed on the transfer conveyance belt 13.
- Image on the photosensitive drums 3a to 3d can be formed on the photosensitive drums 3a to 3d as small as possible with respect to the recording paper P to be formed, and the margin for forming the image can be set small. .
- the setting of the distance from the detection point of the line sensor to the transfer point and the distance from the writing point of the exposure means to the transfer point are changed. This will be described with reference to FIGS. 20 and 21. Note that the distance from the detection point of the line sensor to the transfer point and the distance from the writing point of the exposure means to the transfer point are other than the setting. 06366
- the distance from the detection point of the edge position of the recording paper P to the transfer point by the line sensor is determined by the first image forming station S1 on the first photosensitive drum 3a. Electrostatic latent image by exposure means 8a
- step ST21 of the flowchart of FIG. 20 the image forming operation is started by pressing the start button of the operation unit 405, and then in step ST22, the mode is switched to the blank image forming mode by the switching switch. Is determined. If the determination in step ST22 is NO, which indicates that the mode has not been switched to the borderless image forming mode, the process proceeds to step ST33, in which normal bordered image formation is performed, and then, step ST23 described later is performed. 3 Proceed to 1.
- step ST23 the line sensor 51 conveys the recording paper P at the first detection point R1.
- the horizontal edge position one of the left and right side edge positions
- an actual horizontal width WO 1 in the horizontal direction orthogonal to the transport direction of the recording paper P is obtained from the detection result.
- step ST24 based on the information on the size of the recording paper P to be used, based on the data stored in the data storage unit 406, as shown in FIG.
- the margin W3 in the horizontal direction of the electrostatic latent image on the first photosensitive drum 3a of the forming station S1 (the margin given to the right and left sides of the actual width WO1 of the recording paper P), the registration roller 1 Start of recording paper P by 0, 10 0
- the margin W5 in the vertical direction of the electrostatic latent image including the variation and the margin, and the default value W71 in the vertical direction of the recording paper transport direction of the electrostatic latent image are set to W7, respectively.
- step ST25 the image forming area in the horizontal direction is formed on the first photosensitive drum 3a of the first image forming station S1 by the first exposure means 8a.
- the writing of the electrostatic latent image starts at W 4 (W O 1 + W 3 X 2).
- Each process in steps ST 31 and 32 is the same as each process in steps ST 10 and 11 in FIG. 9, respectively.
- the distance from the point of detection of the edge position of the recording paper P by the line sensor to the transfer point is equal to the distance between the first image forming station S1 and the first photosensitive drum 3a.
- the distance is set to be sufficiently longer than the distance from the writing point of the electrostatic latent image by the first exposure means 8a to the transfer point. For this reason, when detecting the edge position of the recording paper P, after the recording paper P is conveyed and the edge position of the recording paper P is detected at the first detection point R1 by the line sensor 51, the first position is detected. Writing of the electrostatic latent image on the first photosensitive drum 3a by the exposure means 8a is started.
- the size of the electrostatic latent image written on the first photosensitive drum 3a of the first image forming station S1 is changed by the line sensor 51 to the recording paper P at the first detection point R1. It is possible to set a small size based on the edge position detection result. Further, the skew state and the edge position of the recording paper P at the first detection point R1 by the line sensor 51 are also detected at an early stage, and the subsequent electrostatic latent image on the first photosensitive drum 3a is detected. The size of the recording paper P is also quickly changed according to the skew state of the recording paper P, and the amount of waste toner collected without being transferred to the recording paper P can be greatly reduced.
- a monochromatic digital copier is applied as an image forming apparatus.
- the digital copying machine XI includes a scanner section 60, an image forming system for forming an image on recording paper P, and this image forming system.
- a paper transport mechanism 700 that transports the recording paper P to the stem is provided.
- the scanner section 60 includes a document table 61 made of transparent glass or the like, and a reversing automatic document feeder (RADF) 62 for feeding a document onto the document table 61.
- the RADF 62 is a part that reads the image of the original on the mounting table 6 1 to create image data.
- the RADF 62 is provided with an automatic paper feed tray 6 2a for automatically feeding paper to the scanner.
- the transport path for transporting the original on the automatic paper feed tray 6 2a to the original mounting table 6 1, and the scanner cut 63 reads both sides of the original. In order to reverse the original, a reverse path is provided.
- each path is provided with a transport path switching unit and a sensor group (both not shown) for recognizing the document transport position.
- the configuration of RADF 62 is well known in the art, and a detailed description thereof will be omitted.
- the scanner section 60 includes a scanner unit 63 for reading an image of a document conveyed onto the document table 61.
- the scanner unit 63 includes a lamp reflector assembly 64, a plurality of reflection mirrors 65a, 65b, 65c, an optical lens body 66, and a photoelectric conversion element (CCD) 67.
- CCD photoelectric conversion element
- the lamp reflector assembly 64 irradiates a document placed on the document table 61 with light.
- Each of the reflecting mirrors 65a, 65b, and 65c reflects the reflected light from the document once to the left in the figure and then downward, as shown by the two-dot chain line in Fig. 22. And then head to the optical lens body 6 6 As shown in FIG.
- the first scanning unit 6 3 a including the lamp reflector assembly 64 and the reflection mirror 65 a is moved to the document table 6 1. Scans horizontally along and illuminates the entire document.
- the second scanning unit 63b composed of the reflecting mirrors 65b and 65c is moved at a predetermined speed (to the first scanning unit 63a) with respect to the first scanning unit 63a. Move in the same direction at half the speed).
- each of the reflecting mirrors 65a, 65b, and 65c and passing through the optical lens body 66 forms an image on a photoelectric conversion element 67, and the light is reflected by the photoelectric conversion element 67.
- the reflected light is converted into an electric signal (original image data).
- the image data thus obtained is transmitted to an image processing unit (not shown), which will be described later. After various processes are performed, the image data is temporarily stored in an image memory (not shown) and output. The image data in the image memory is read out according to the instruction and used for the image forming operation by the image forming system.
- the image forming system includes a laser writing unit 81 and an electrophotographic process unit 82.
- the laser writing unit 81 converts the laser light based on the original image data converted by the photoelectric conversion element 67 or the image data transmitted from the personal computer or the like into a photoconductor as an image carrier of the electrophotographic process unit 82. It irradiates the surface of the drum 3.
- the laser writing unit 81 is a semiconductor laser light source that irradiates a laser beam corresponding to the image data, a polygon mirror that deflects the laser beam at a constant angular speed, and a polygon mirror that deflects the laser beam at a constant angular speed. It has an f-lens and the like that corrects the laser beam to scan the photosensitive drum 3 at a constant speed.
- the photoreceptor drum 3 rotates in the direction indicated by the arrow in FIG. 22, and the laser beam from the laser writing unit 81 is reflected by the reflection mirror 81 a so that the laser beam is emitted. An image is formed.
- the electrophotographic process section 82 is provided around the photosensitive drum 3 with a charger.
- the charger 4 charges the surface of the photosensitive drum 3 to a predetermined potential before an electrostatic latent image is formed.
- the developing device 5 develops the electrostatic latent image formed on the surface of the photoconductor drum 3 into a visible image using toner.
- the transfer device 6 transfers the toner image formed on the surface of the photosensitive drum 3 to the recording paper P.
- the fixing device 2 fixes the toner image transferred onto the recording paper P onto the recording paper P by heating, and includes a heating roller 21 and a pressure roller 22.
- the static eliminator 83 removes residual charges on the surface of the photosensitive drum 3.
- the peeling device 7 removes the toner remaining on the surface of the photosensitive drum 3 after the toner transfer. In this case, the cleaning device 7 is formed integrally with the container.
- the surface of the photosensitive drum 3 is charged to a predetermined potential by the charger 4, and the laser writing unit 81 emits a laser beam based on the image data to the photosensitive drum. Irradiates the surface of 3 to form an electrostatic latent image. Thereafter, the developing device 5 develops a visible image with toner on the surface of the photosensitive drum 3, and the toner image is transferred by the transfer device 6 to the recording paper P fed from the paper transport mechanism 700. You. Thereafter, the recording paper P is heated by the fixing device 2, and the toner image is fixed.
- the paper transport mechanism 700 stores the first, second, and third paper cassettes 71, 72, 73, and multi-bypass trays 74, one by one.
- the recording paper P on which the image has been formed is transported to the first, second, or third discharge trays 91, 92, and 93 while the image is formed by the image forming system.
- the paper transport mechanism 700 is provided with a double-sided copy unit 7 for once recovering the recording paper P having an image formed on one side and then performing image formation by the image forming system on the other side. Has five.
- Each of the paper cassettes 7 1, 7 2, 7 3 contains recording paper P of a different size, and the recording paper P from the paper cassette containing the recording paper P of the size desired by the user. Are sequentially taken out one by one and sequentially conveyed to the image forming system via a conveyance path 70.
- the transport path 70 of the paper transport mechanism 700 includes a main transport path 76 and a reverse transport path 77.
- the main transport path 76 has one end (upstream end in the recording paper transport direction) that is branched to face the paper cassettes 71, 72, 73, and the discharge side of the multi-purpose tray 74, respectively. And the other end (downstream end in the recording paper transport direction) is
- One end (upper end in the figure) of the reversing conveyance path 77 is connected to the main conveyance path 76 on the downstream side (left side in the figure) of the position where the fixing device 2 is provided, and an intermediate portion (upper side in the figure) (A central part in the downward direction) is branched into first and second branch roads 77A and 77B.
- the first branch 77 A extends vertically downward.
- one end of the second branch path 77B faces the loading side of the duplex copying unit 75.
- First and second branch claws 77 a and 77 b are provided at a connection portion between the main transport path 76 and the reverse transport path 77 and at a branch portion of the reverse transport path 77.
- the first branch pawl 77 a closes the discharge side of the main transport path 76 with the first position for closing the reverse transport path 77, and connects the main transport path 76 with the reverse transport path 77. It is rotatable around the horizontal axis between the second position.
- the recording paper P that has passed through the image forming system is discharged to the discharge trays 91, 92, and 93 as it is.
- the first branch claw 77a is at the second position, the recording paper P that has passed through the image forming system is supplied to the reverse conveyance path 77.
- the second branch pawl 77 b opens the first branch path 77 A of the reversing conveyance path 77, and It is rotatable about a horizontal axis between a first position for closing the two branch path 77B and a second position for opening the second branch path 77B and closing the first branch path 77A. It has become.
- the recording sheet P conveyed to the reverse conveyance path 77 is guided to the first branch path 77 A and conveyed to the lower end position.
- the recording paper P is transported to the second branch path 77 B via the branching part, and duplex copying is performed.
- Unit 75 is supplied. That is, the recording paper P was supplied to the duplex copying unit 75 via the first branch path 77A and the second branch path 77B, and the recording paper P was supplied to the image forming system. In this case, the image is formed upside down so that the image can be formed on the back surface of the recording paper P.
- Pickup rollers 78 are provided at the upstream end of the main transport path 76 (the part facing the discharge side of the paper cassettes 71, 72, 73, the multi-purpose tray 74, and the duplex copying unit 75). Is established. A plurality of paper feed rollers 79 for feeding the picked-up recording paper P to the main transport path 76 are provided downstream of each pickup roller 78. The recording paper P stored in the paper cassettes 71, 72, 73, the multi-purpose tray 74, and the duplex copying unit 75 is selected by the rotation of the pickup roller 78 and the paper supply roller 79. Alternatively, paper can be fed to the main transport path 76 one by one.
- the paper discharge unit of the digital copying machine X1 the first and second paper discharge trays 91 and 92 of the upper and lower two stages and the inside of the post-processing device 90 are not shown.
- one third paper output tray 93 equipped with a staple finisher. That is, inside the post-processing device 90, there is provided a transport path that connects the downstream end of the main transport path 76 and each of the paper discharge trays 91, 92, and 93, and the recording paper P is discharged.
- the transport path can be switched according to the paper output trays 91, 92, and 93 on which the paper is to be printed.
- registration rollers 10 and 10 for temporarily holding the recording paper P sequentially transported to the image forming system via the transport path 70 are provided. Is provided. Also, the photosensitive drum 3 T JP2004 / 006366
- the edge position (end position) of the recording paper P transported toward the transfer point Line sensor 55 for detecting the edge sensor 55 is provided above one side in a direction orthogonal to the transport direction of the recording paper P.
- the line sensor 55 is provided integrally with an illuminating means (not shown) for irradiating irradiation light toward the transport path 70 (downward) and a light receiving means. The edge position of the recording paper P is detected based on whether light is reflected by the recording paper P being conveyed and received by the light receiving means.
- the line sensor 55 is provided immediately downstream of the registration rollers 10 and 10 in the recording paper conveyance direction, and the registration rollers 10 and 10 are detected before the line sensor 55 detects the edge position of the recording paper P.
- the inclination of the conveyance of the recording paper P is corrected to some extent, and the position of the toner image (image) on the photosensitive drum 3 with respect to the recording paper P is adjusted.
- the distance from the point where the edge position of the recording paper P is detected by the line sensor 55 to the transfer point is determined from the writing point of the electrostatic latent image (image) by the laser writing unit 81 on the photosensitive drum 3.
- the distance is set to be shorter than the distance to the transfer point.
- Reference numeral 40 in FIG. 22 indicates a control unit.
- an image on the photosensitive drum 3 larger than the size of the recording paper P is transferred to the recording paper P conveyed to the transfer point.
- the image on the photosensitive drum 3 transferred to the middle of the recording paper P based on the detection result of the line sensor 55 thereafter.
- the size changes. That is, the size of the image formed on the photosensitive drum 3 is changed before and after the detection result of the edge position of the recording paper P is obtained by the line sensor 55. Therefore, before the detection by the line sensor 55, even if the edge position of the recording paper P is not detected, the image on the photosensitive drum 3 that is larger than the size of the recording paper P causes the conveyance deviation of the recording paper P. It is possible to transfer a good image onto recording paper P without causing image loss.
- the size of the image on the photosensitive drum 3 is recorded based on the detection result of the edge position of the recording paper P.
- the size is changed according to the edge position of paper P.
- the amount of toner collected by the cleaning device 7 without being transferred to the recording paper P is reduced as much as possible, and waste of toner can be suppressed and toner can be economically consumed.
- the line sensor 55 can be provided close to the transfer point.
- the transport path of the recording paper P from the detection point of the edge position of the recording paper P by the line sensor 55 to the transfer point is shortened in the transport direction, and the digital copying machine X1 is made compact.
- the time required for image formation can be shortened.
- the line sensor 55 is integrally provided with the illuminating means and the light receiving means, the line sensor 55 and the illuminating means can be integrated, so that the assembling can be performed easily and a commercially available compact scanner can be used.
- a line image sensor head can be used.
- the line sensor 55 detects only the edge position of the recording paper P.
- This will be described below as a fifth embodiment in which the edge position of the recording paper P is changed to be detected at two points in the recording paper transport direction, and the skew state of the recording paper P can be detected.
- the same components as those of the fourth embodiment are denoted by the same reference numerals, and the description will be made mainly on the differences.
- the recording conveyed to the transfer point is performed before the edge position and the skew state of the recording paper P are detected by the line sensor 55.
- the image on the photosensitive drum 3 larger than the size of the recording paper P is transferred onto the paper P.
- the recording paper P is detected.
- the size of the image on the photosensitive drum 3 to be transferred on the way is changed.
- the size of the image formed on the photosensitive drum 3 is greatly changed before and after the detection of the edge position and the skew state of the recording paper P by the line sensor 55 and after the detection is obtained. become. Therefore, before the edge position and the skew state of the recording paper P are detected by the line sensor 55, even if the edge position and the skew state of the recording paper P are not detected, the size is smaller than the size of the recording paper P.
- the large image on the photosensitive drum 3 makes it possible to transfer a good image onto the recording paper P without causing the image to be lost due to the conveyance of the recording paper P.
- the edge position of the recording paper P and the skew state are not changed. Based on the detection result, the size of the image on the photosensitive drum 3 is changed to a size in accordance with the edge position of the recording paper P and the skew state (inclination angle 0). As a result, the amount of toner collected by the cleaning device 7 without being transferred to the recording paper P is reduced as much as possible, and it is possible to suppress waste of toner and economically consume toner. The cycle until the filled toner is full can be extended.
- the collected toner is prevented from partially accumulating in the container, and the collected toner is partially leaked.
- the c can be prevented cleaning failure, by which an image is formed on the previously detected edge position and skew state of the recording paper P by the line sensor 5 5 on the photosensitive drum 3, the transfer of Rainse capacitors 5 5 It becomes possible to provide it close to the point.
- the transport path of the recording paper P from the detection point of the edge position of the recording paper P by the line sensor 55 to the transfer point is shortened in the transport direction, and the digital copying machine X1 can be made compact.
- the time required for image formation is short can do.
- the present invention is not limited to the above embodiments, and includes various other modifications.
- the line sensors 51 and 55 are provided on one side in a direction orthogonal to the transport direction of the recording paper P, but as shown in FIG. 23, the line sensors 51 and 55 are perpendicular to the transport direction of the recording paper P.
- Line sensors 51, 51 (or 55, 55) may be provided on one side (the lower side in FIG. 23) and the other side (the upper side in FIG. 23), respectively.
- a line sensor extending in the left-right direction extends from one side (lower side in Fig. 24) to the other side (upper side in Fig. 24) in the direction orthogonal to the transport direction of the recording paper P. 5 and 6 may be provided.
- the edge positions on both the left and right sides of the recording paper P are more accurately detected, and the edge positions with high accuracy can be detected.
- the distance from the detection point of the edge position of the recording paper P by the line sensor to the transfer point is determined by the first photosensitive drum 3 a (The distance between the writing point of the electrostatic latent image by the first exposure means 8a (laser writing unit 81) and the transfer point by the first exposure means 8a to the photosensitive drum 3) was set longer, but the recording paper by the line sensor was used.
- the distance from the detection point of the edge position of P to the transfer point may be set to be shorter than the distance from the writing point of the electrostatic latent image by the exposure means to the photosensitive drum to the transfer point.
- the skew state of the recording paper when detecting the skew state of the recording paper, it is necessary to transport the recording paper to some extent and detect the edge position of the recording paper P at the second detection point R2 by the line sensor. However, it takes time to detect the skew state of the recording sheet, and the skew state of the recording sheet is detected after the timing of starting the writing of the electrostatic latent image on the photosensitive drum by the exposure unit. If the skew state of the recording paper is detected, the size of the subsequent image on the photosensitive drum is quickly changed according to the skew state of the recording paper, and the waste collected without being transferred to the recording paper is changed. The amount of the toner can be reduced.
- laser writing is performed on the photosensitive drum 3.
- the electrostatic latent image (image) is written by the embedding unit 81, but the electrostatic latent image may be written by using a solid-state scanning type optical writing head using a light emitting element array such as £ 0 ⁇ £. .
- the image forming apparatus of the present invention is extremely suitable for an electrophotographic image forming apparatus such as a color or monochrome digital copying machine or printer.
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Abstract
Description
Claims
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
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US10/555,862 US7536125B2 (en) | 2003-05-08 | 2004-04-30 | Image forming apparatus capable of suppressing developer waste |
Applications Claiming Priority (4)
Application Number | Priority Date | Filing Date | Title |
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JP2003-130453 | 2003-05-08 | ||
JP2003130453A JP2004333935A (ja) | 2003-05-08 | 2003-05-08 | 画像形成装置 |
JP2003134609A JP2004341051A (ja) | 2003-05-13 | 2003-05-13 | 画像形成装置 |
JP2003-134609 | 2003-05-13 |
Publications (1)
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WO2004099883A1 true WO2004099883A1 (ja) | 2004-11-18 |
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PCT/JP2004/006366 WO2004099883A1 (ja) | 2003-05-08 | 2004-04-30 | 画像形成装置 |
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US (1) | US7536125B2 (ja) |
WO (1) | WO2004099883A1 (ja) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
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US8027610B2 (en) * | 2006-02-27 | 2011-09-27 | Canon Kabushiki Kaisha | Image forming apparatus and control method for printing without a margin |
US8447202B2 (en) * | 2006-02-24 | 2013-05-21 | Canon Kabushiki Kaisha | Printing without margins-enabled image forming apparatus and control method |
EP1780604B1 (en) * | 2005-10-31 | 2016-06-08 | Canon Kabushiki Kaisha | Image forming apparatus, control method for registration error correction, and program |
Families Citing this family (10)
Publication number | Priority date | Publication date | Assignee | Title |
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JP2007030192A (ja) * | 2005-07-22 | 2007-02-08 | Konica Minolta Business Technologies Inc | 画像形成装置及びプログラム |
JP2007041112A (ja) * | 2005-08-01 | 2007-02-15 | Konica Minolta Business Technologies Inc | 画像形成装置 |
JP2009096099A (ja) * | 2007-10-18 | 2009-05-07 | Brother Ind Ltd | 画像記録装置 |
JP5043611B2 (ja) * | 2007-11-27 | 2012-10-10 | キヤノン株式会社 | 画像形成装置 |
US20100158545A1 (en) * | 2008-12-19 | 2010-06-24 | Eastman Kodak Company | Electophotographic borderless printing method and apparatus |
US8280297B2 (en) * | 2008-12-19 | 2012-10-02 | Eastman Kodak Company | Electophotographic borderless printing method and apparatus |
US8705992B2 (en) * | 2011-10-31 | 2014-04-22 | Eastman Kodak Company | Edge printing module |
JP6106918B2 (ja) * | 2012-01-26 | 2017-04-05 | 富士ゼロックス株式会社 | 画像形成装置 |
JP6083413B2 (ja) * | 2014-05-26 | 2017-02-22 | コニカミノルタ株式会社 | 画像形成装置および画像形成方法 |
JP7247668B2 (ja) * | 2019-03-11 | 2023-03-29 | 株式会社リコー | 画像検査装置、及び印刷システム |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH0258763U (ja) * | 1988-10-20 | 1990-04-26 | ||
JP2001347720A (ja) * | 2000-06-08 | 2001-12-18 | Canon Aptex Inc | 印刷制御装置及び方法 |
JP2002189381A (ja) * | 2000-12-20 | 2002-07-05 | Canon Inc | 画像形成装置 |
Family Cites Families (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH06301256A (ja) | 1993-04-12 | 1994-10-28 | Fuji Xerox Co Ltd | 画像形成装置のイメージ書き込み装置 |
JPH07148970A (ja) | 1993-11-30 | 1995-06-13 | Ricoh Co Ltd | デジタル画像形成装置 |
JPH10186951A (ja) | 1996-12-26 | 1998-07-14 | Canon Inc | 画像形成装置 |
-
2004
- 2004-04-30 WO PCT/JP2004/006366 patent/WO2004099883A1/ja active Application Filing
- 2004-04-30 US US10/555,862 patent/US7536125B2/en not_active Expired - Fee Related
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH0258763U (ja) * | 1988-10-20 | 1990-04-26 | ||
JP2001347720A (ja) * | 2000-06-08 | 2001-12-18 | Canon Aptex Inc | 印刷制御装置及び方法 |
JP2002189381A (ja) * | 2000-12-20 | 2002-07-05 | Canon Inc | 画像形成装置 |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP1780604B1 (en) * | 2005-10-31 | 2016-06-08 | Canon Kabushiki Kaisha | Image forming apparatus, control method for registration error correction, and program |
US8447202B2 (en) * | 2006-02-24 | 2013-05-21 | Canon Kabushiki Kaisha | Printing without margins-enabled image forming apparatus and control method |
US8027610B2 (en) * | 2006-02-27 | 2011-09-27 | Canon Kabushiki Kaisha | Image forming apparatus and control method for printing without a margin |
Also Published As
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US7536125B2 (en) | 2009-05-19 |
US20060216047A1 (en) | 2006-09-28 |
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