JP2007015355A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus capable of improving inspection efficiency by shortening the time for inspecting an image forming position. <P>SOLUTION: The image forming apparatus comprises an image forming means for forming a color image and a control means for instructing the image forming means to form an image for adjustment when receiving an instruction to form the image for adjustment. The control means forms images for adjustment 80C, 80M, 80Y, and 80K having two or more colors of intersections in which lines of the same color intersect one another and abutting parts in which tips of the lines of different colors abut with each other. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an image forming apparatus including an image forming unit that forms a color image and a control unit that causes the image forming unit to form an adjustment image when an adjustment image forming instruction is received.

Some image forming apparatuses such as copiers and multi-function machines can form color images. For example, C (cyan), M (magenta), Y (yellow), and K (black) color component images are displayed. Overlapping to form a color image. In order to maintain good image quality of color images, it is important to minimize the amount of shift in the formation position of each color component image. Therefore, an adjustment image of each color component image of C, M, Y, and K is formed, the presence / absence of a color shift of each color component image is inspected, and if there is a color shift, the formation position is corrected. (For example, refer to Patent Document 1).
JP 2001-277599 A

  The inspection for the presence or absence of color misregistration is performed by a measuring machine having a CCD (Charge Coupled Device) or the like, or visually inspected by an inspector. In the case of using a measuring machine, the inspection takes time, but the inspection accuracy is high. In the case of visual inspection, the inspection accuracy is low, but the inspection time is short. As a visual adjustment image, an image obtained by superimposing grid-like figures of respective color components is often used. However, when all the lattice patterns of C, M, Y, and K are overlapped, it is difficult to determine the presence or absence of color misregistration. Therefore, the overlap of K and C, the overlap of K and Y, Since the inspection is performed by separately forming the superimposed M, three types of inspection images are required, and there is a problem that the inspection takes time. In addition, as an adjustment image for a measuring instrument, C, M, Y, and K inspection patterns are formed, for example, the formation positions of C, M, and Y patterns based on the K pattern are detected and detected. The presence or absence of color misregistration is determined based on the determined position. Therefore, when the inspection by the measuring machine and the visual inspection are used together, it is necessary to prepare the adjustment image for the measuring machine and the adjustment image for the visual observation separately. When the adjustment images are prepared separately, there is a problem that the labor for preparation and inspection increases and the labor for managing the adjustment images increases.

  The present invention has been made in view of such circumstances, and an adjustment image having an intersecting portion where lines of the same color intersect and an abutting portion against which the tip of a line of a different color is abutted is controlled. It is an object of the present invention to provide an image forming apparatus that can shorten the inspection time and improve the inspection efficiency.

  Further, according to the present invention, the adjustment image includes a plurality of color cross graphics and is arranged so that tips of the cross graphics of different colors abut each other, or includes a plurality of color cross graphics and a straight line, Another object of the present invention is to provide an image forming apparatus that can easily grasp an inspection point by arranging the ends of the graphic and the straight line to face each other.

  Further, according to the present invention, the adjustment image includes a straight line that constitutes the cross figure and a straight line that is perpendicular to the straight line that are arranged so that the ends abut against each other. Another object of the present invention is to provide an image forming apparatus that can easily perform the above.

  Another object of the present invention is to provide an image forming apparatus that can easily grasp an inspection point when the adjustment image includes a bowl-shaped figure or a square-shaped figure.

  Further, according to the present invention, the adjustment image is a block in which unit images of four colors including a cross shape are arranged in two rows and two columns, and a plurality of columns in which a plurality of blocks are arranged are alternately shifted by a half block. However, another object of the present invention is to provide an image forming apparatus that can perform inspection efficiently by bringing inspection points of each color component close to each other.

  According to another aspect of the present invention, there is provided an image forming apparatus capable of easily specifying an inspection point by including a plurality of cross figures arranged in a direction perpendicular to a sheet conveyance direction. Objective.

  Further, the present invention provides an image forming apparatus capable of easily grasping an inspection point by including a figure in which the adjustment image includes two quadrilaterals so that one diagonal of each quadrilateral is on the same straight line. For other purposes.

  An image forming apparatus according to the present invention includes: an image forming unit that forms a color image; and a control unit that causes the image forming unit to form an adjustment image when an adjustment image formation instruction is received. The control means is configured to form an adjustment image having an intersecting portion where lines of the same color intersect and an abutting portion against which the tip of a line of a different color is abutted. And

  In the image forming apparatus according to the present invention, the adjustment image includes a plurality of colors of cross shapes and is arranged so that tips of the cross shapes of different colors abut each other, or includes a plurality of colors of cross shapes and straight lines, The cross-shaped figures and the straight lines having different shapes are arranged so that the tips of the straight lines abut against each other.

  The image forming apparatus according to the present invention is characterized in that the adjustment image includes a straight line that is perpendicular to the straight line that is arranged such that the straight line that forms the cross-shaped figure and the leading ends abut each other.

  The image forming apparatus according to the present invention is characterized in that the adjustment image includes a bowl-shaped figure or a rice field-shaped figure.

  In the image forming apparatus according to the present invention, the adjustment image is formed by arranging four color unit images including a cross figure in two rows and two columns as one block, and alternately arranging a plurality of columns in which a plurality of blocks are arranged. It is characterized by being arranged while being shifted by a half block.

  The image forming apparatus according to the present invention is characterized in that the adjustment image includes a plurality of cross figures arranged in a direction perpendicular to a sheet conveyance direction on which the adjustment image is formed.

  The image forming apparatus according to the present invention is characterized in that the adjustment image includes a figure in which two quadrangles are arranged so that one diagonal line of each quadrangle is on the same straight line.

  In the present invention, the control means causes the image forming means to form an adjustment image having a crossing portion where lines of the same color intersect and an abutting portion where the tip of a line of a different color is abutted. It is possible to detect the misalignment of the intersecting portion with a measuring machine having the above and the like, and an inspector or the like can detect the misalignment in the abutting portion visually. Since the adjustment image includes crossing portions and butting portions of a plurality of colors, the inspection for all colors can be performed with one type of adjustment image, and the inspection time can be shortened. Further, by inspecting the intersecting portion with a measuring machine and visually inspecting the abutting portion, the inspection by the measuring machine and the visual inspection can be performed using the same adjustment image.

  In the present invention, the adjustment image includes a plurality of color crosses and is arranged so that the tips of the crosses of different colors abut each other, or includes a plurality of color crosses and straight lines, and the crosses of different colors In addition, the center of the cross figure (intersection) can be used for inspection by a measuring machine, and the tip of the cross figure (butting part) is used for visual inspection. The inspection point can be easily grasped.

  In the present invention, the adjustment image includes a straight line that constitutes the cross shape and a straight line that is perpendicular to the straight line so that the ends abut against each other, and the abutting portion is bent at a right angle. In addition, it is possible to easily inspect misalignment in two orthogonal directions (for example, the main scanning direction and the sub-scanning direction).

  In the present invention, the adjustment image includes a bowl-shaped figure or a rice field-shaped figure, and in the case of performing an inspection by a measuring machine, the center of the bowl-shaped figure or the rice field-shaped figure (cross intersection). Becomes an inspection point, and when visual inspection is performed, since adjacent portions (butting portions) between bowl-shaped figures or rice-shaped figures are inspection points, it is easy to grasp the inspection points.

  In the present invention, the adjustment image is one block of four color unit images including a cross shape arranged in two rows and two columns, and a plurality of rows in which a plurality of blocks are arranged are alternately shifted by a half block. Since they are arranged, it is possible to arrange the unit images of the other three colors so as to be adjacent to the unit image of a certain color, and the inspection can be performed efficiently by bringing the inspection points of the respective color components close to each other. In addition, since an inspection point of an arbitrary block among a plurality of blocks can be inspected, it is possible to inspect an arbitrary position of the sheet on which the adjustment image is formed. For example, inspection can be performed at inspection points along the main scanning direction or the sub-scanning direction.

  In the present invention, the adjustment image includes a plurality of cross-shaped figures arranged perpendicular to the sheet conveyance direction, and the cross-shaped figures are used as scales to be used as a reference position when inspecting visually or by a measuring machine. The inspection point in the adjustment image can be easily specified, and the inspection efficiency can be improved. Further, the fθ lens extending in the direction perpendicular to the sheet conveyance direction (main scanning direction) has a small center shift, but tends to have a large end shift, so the cross shape is used for the fθ lens inspection. It is also possible.

  In the present invention, the image for adjustment includes a figure in which two squares are arranged so that one diagonal line of each square is on the same straight line, and like a bowl-like figure or a rice-shaped figure, The inspection point can be easily grasped.

  According to the present invention, all colors can be inspected with one type of adjustment image, and the inspection time can be shortened to improve inspection efficiency. Further, the inspection by the measuring machine and the visual inspection can be performed using the same adjustment image, and the labor for preparing, managing, and inspecting the adjustment image can be reduced.

  According to the present invention, the inspection point can be easily grasped.

  According to the present invention, it is possible to easily inspect a positional deviation in two orthogonal directions.

  According to the present invention, inspection can be performed efficiently by bringing inspection points of each color component close to each other.

  According to the present invention, it is possible to easily specify inspection points in an adjustment image and improve inspection efficiency.

Hereinafter, the present invention will be specifically described with reference to the drawings showing embodiments thereof.
FIG. 1 is a schematic diagram showing a configuration of a main part of an image forming apparatus according to the present invention. The image forming apparatus mainly includes a photosensitive drum 10 on which an image is formed, a laser diode 42 that outputs a laser beam, a first mirror 44 that guides the laser beam output from the laser diode 42 to the photosensitive drum 10, and a polygon. The mirror 40, the second mirror 46, the developing roller 24 for developing the latent image formed on the photosensitive drum 10 by the laser beam, the transfer belt 30 to which the image formed on the photosensitive drum 10 is transferred, and the transfer belt 30 A transfer roller 36 for transferring the image transferred to the sheet (sheet) 50 and a fixing roller 38 for fixing the image transferred to the sheet.

  The photosensitive drum 10 includes a photosensitive drum 10K for black, a photosensitive drum 10C for cyan, a photosensitive drum 10M for magenta, and a photosensitive drum 10Y for yellow. Similarly, the developing roller 24 includes a developing roller 24K for black, a developing roller 24C for cyan, a developing roller 24M for magenta, and a developing roller 24Y for yellow. The laser diode 42 includes a laser diode 42K for black, a laser diode 42C for cyan, a laser diode 42M for magenta, and a laser diode 42Y for yellow.

  The first mirror 44 includes a cyan first mirror 44C that guides laser beams output from the cyan laser diode 42C, the magenta laser diode 42M, and the yellow laser diode 42Y to the polygon mirror 40, A first mirror 44M for magenta and a first mirror 44Y for yellow are included. The second mirror 46 guides the laser beam reflected by the polygon mirror 40 to each of the black photosensitive drum 10K, the cyan photosensitive drum 10C, the magenta photosensitive drum 10M, and the yellow photosensitive drum 10Y. A second mirror 46K for black, a second mirror 46C for cyan, a second mirror 46M for magenta, and a second mirror 46Y for yellow are included.

  The transfer belt 30 has a loop shape, and the photosensitive drums 10K, 10C, 10M, and 10Y for each color component are arranged side by side so as to face the surface of the transfer belt 30. Further, the image transferred to the transfer belt 30 is moved from the right to the left in the drawing with respect to the photosensitive drum 10 by the belt driving roller 32 inscribed in the transfer belt 30. A transfer roller 36 is disposed so as to face the belt driving roller 32 with the transfer belt 30 in between. An image is transferred from the transfer belt 30 onto a sheet 50 passing through the transfer roller 36 and is fixed by a fixing roller 38. Is done.

  FIG. 2 is a block diagram illustrating a main configuration of the image forming apparatus. The image forming apparatus includes an LSU (Laser Scanning Unit) 64 including laser diodes 42K, 42C, 42M, and 42Y and a polygon mirror 40, photosensitive drums 10K, 10C, 10M, and 10Y, and developing rollers 24K, 24C, and the like. A developing unit 72 including 24M and 24Y, a fixing unit 74 including a fixing roller 38 and a heater 76, a driving unit 66 for driving the photosensitive drum 10, the belt driving roller 32, the polygon mirror 40, and the like, and a document image are read. An image input unit 62 such as an image scanner, a control unit 60 such as a CPU (Central Processing Unit) that controls the LSU 64, the drive unit 66, the image input unit 62, the developing unit 72, and the fixing unit 74, and the control unit 60. And an image memory 34, a display unit 68, and an operation unit 70 connected thereto. The control unit 60 includes a ROM (Read Only Memory) that stores a control program and the like, and a RAM (Random Access Memory) that stores temporary data and the like. The operation unit 70 includes various operation keys such as a start key, a cancel key, a numeric keypad, and a function key. The display unit 68 uses a liquid crystal display panel, but the display unit 68 can be used as the operation unit 70 by using, for example, a touch panel.

  The image forming apparatus can form a color image in which a plurality of color component images are superimposed on the paper 50, but the control unit (control unit) 60 is controlled by the image memory 34 in response to an operation on the operation unit 4. It is also possible to prepare an adjustment image of the formation position of each color component and form the prepared adjustment image. FIGS. 3A to 3C are diagrams showing an outline of the inspection of the formation position of each color component using the adjustment image. As shown in FIG. 3 (a), cross patterns (unit images) 80C, 80M, 80Y, and 80K of C, M, Y, and K color components are arranged in two rows and two columns so that the tips meet each other. A unit image block is formed. 3 (b), the formation position of the Y cross pattern 80Y is shifted to the right in FIG. 3 (b), and the formation position of the M cross pattern 80M is downward in FIG. 3 (c). Such a shift is inspected.

  FIG. 4A is a diagram illustrating an example of unit image blocks of an adjustment image used in the present embodiment, FIG. 4B is a diagram illustrating an arrangement example of a plurality of unit image blocks, and FIG. It is a figure which shows the example of the formation area of the image for adjustment. As shown in FIG. 4A, the unit image block includes wrinkle patterns (unit images) 82C, 82M, 82Y, and 82K for the respective color components C, M, Y, and K, and the tip of the cross portion included in the wrinkle pattern. They are arranged in 2 rows and 2 columns so that the tips of the ridge patterns and the tips of the heel patterns abut each other. In the example shown in the figure, a Y haze pattern 82Y is arranged above the K haze pattern 82K, and an M haze pattern 82M is arranged on the left side of the K haze pattern 82K. Each wrinkle pattern 82C, 82M, 82Y, 82K has a line width of 1 dot (42 μm), and a vertical width and a horizontal width of 61 dots. As shown in FIG. 4B, the adjustment image includes a plurality of unit image blocks arranged so that the tips of the cross portions included in the heel pattern and the tips of the heels abut against each other. However, as shown in FIG. 4B, each unit image block is shifted by one unit image (half unit image block) in the vertical direction, and the right side of the K haze pattern 82K is the C haze pattern 82C. It is arranged to be.

  As shown in FIG. 5, a plurality of cross patterns 94 are arranged along the right edge of the sheet 90 as an adjustment image, and a plurality of unit image blocks are arranged in the other part (formation region 92) of the sheet 90. FIG. 6 is an enlarged view of a main part showing details of the arrangement of the cross pattern 94 (black in the example in the figure). The cross pattern 94K has a line width of 1 dot, and a vertical width and a horizontal width of 61 dots, so that the vertical coordinates of the center point of the K collar pattern 82K and the center point of the cross pattern 94K are the same. , K are arranged at intervals of 59 dots in the right direction from the K wrinkle pattern 82K. In addition, the cross pattern 94K is formed every time four K wrinkle patterns 82K are formed (every 480 dots). Further, as shown in the enlarged view of the main part showing the details of the arrangement of the cross pattern 94 in FIG. 7, the Y cross pattern 94Y, the M cross pattern 94M, and the C cross pattern 94C are arranged between the K cross patterns 94K. It is also possible to arrange them at intervals.

  FIG. 8 is a flowchart showing an example of arrangement processing of a plurality of unit image blocks when preparing an adjustment image. As shown in FIG. 5, the upper right of the formation area 92 in which the unit image block is arranged is the origin (X0, Y0), the lower direction is the X direction, and the left direction is the Y direction. The sheet conveyance direction is the -Y direction, and the cross patterns 94 are arranged in the X direction. The unit image block and the cross pattern are stored in advance in the ROM. The control unit 60 sets variables N and M stored in the RAM to N = 0 and M = 0 (S10), and coordinates (X0 + 120N, Y0 + 120M) in the adjustment image forming area 92 stored in the image memory 34. ) Is arranged (S12), and 1 is added to N stored in the RAM (S14). The same processing is repeated until N exceeds a predetermined value (determined according to the paper size, 54 in the illustrated example) (S16: NO, S12, S14). When N exceeds 54 (S16: YES), the control unit 60 resets N stored in the RAM to 0 and adds 1 to M (S18).

  Subsequently, the control unit 60 arranges unit image blocks at the coordinates (X0 + 60 + 120N, Y0 + 120M) in the adjustment image forming area 92 stored in the image memory 34 (S20), and then stores N stored in the RAM. 1 is added to (S22). The same processing is repeated until N exceeds 54 (S24: NO, S20, S22). When N exceeds 54 (S24: YES), the control unit 60 resets N stored in the RAM to 0 and adds 1 to M (S26). When M has reached a predetermined value (determined according to the paper size, 40 in the example in the figure) (S28: YES), the preparation of the adjustment image is completed, and M has not reached 40 (S28: NO). Repeats the same processing (S12 to S26).

  Based on the adjustment image stored in the image memory 34, the control unit 60 controls the LSU 64 and the like, and each color component of the adjustment image is formed on the photosensitive drums 10K, 10C, 10M, and 10Y and transferred to the transfer belt 30. And developed on paper. Using the adjustment image, as shown in FIG. 4B, the misalignment of the central parts (intersections) PC, PM, PY, PK of the eyelid patterns 82C, 82M, 82Y, 82K is inspected using a measuring machine. , The misalignment between the K wrinkle pattern 82K and the butting portions QC, QM, QY of the C, M, Y wrinkle patterns 82C, 82Y, 82K can be visually inspected. Since the abutting portions QC, QM, and QY are positioned around the heel pattern 82K, the inspection position can be easily grasped, and the visual inspection can be efficiently performed. In addition, since the intersections PC, PM, PY, and PK are included, the inspection by the measuring machine can be performed using the same adjustment image, and the inspection efficiency is improved.

  In the above-described embodiment, the bowl-shaped unit image is used. However, the basic image only needs to include a cross shape. For example, another example of the unit image block of the adjustment image in FIG. As shown in the drawing and the drawing showing the arrangement example of the plurality of unit image blocks in FIG. 9B, the square-shaped unit images 84C, 84M, 84Y, and 84K are used, or the adjustment image in FIG. As shown in the figure showing another example of the unit image block and the figure showing the arrangement example of the plurality of unit image blocks in FIG. It is also possible to use a unit image in which two quadrilaterals are arranged so that one diagonal of each quadrangle is on the same straight line by connecting the lower and right ends in a dogleg shape.

  In each of the above-described embodiments, the scissors pattern or the U-shaped pattern has been described as an example. However, in the adjustment image, the intersections where the same color lines intersect and the straight ends of different color components protrude from each other. It is only necessary to have at least an abutting portion that is applied. For example, an adjustment image can be configured by a cross pattern of each color component and a straight line of a different color in which the cross pattern and the tip are abutted. It is.

1 is a schematic diagram illustrating a configuration of a main part of an image forming apparatus according to the present invention. 1 is a block diagram illustrating a main configuration of an image forming apparatus. It is a figure which shows the outline | summary of the test | inspection of the formation position of each color component using the image for adjustment. (A) is a figure which shows the example of the unit image block of the image for an adjustment used by this Embodiment, (b) is a figure which shows the example of arrangement | positioning of several unit image block. It is a figure which shows the example of the formation area of the image for adjustment. It is a principal part enlarged view which shows the detail of arrangement | positioning of a cross pattern. It is a principal part enlarged view which shows the detail of arrangement | positioning of a cross pattern. It is a flowchart which shows the example of the arrangement | positioning process of the several unit image block at the time of preparing the image for adjustment. (A) is a figure which shows the other example of the unit image block of the image for adjustment, (b) is a figure which shows the example of arrangement | positioning of several unit image block. (A) is a figure which shows the other example of the unit image block of the image for adjustment, (b) is a figure which shows the example of arrangement | positioning of several unit image block.

Explanation of symbols

10K, 10C, 10M, 10Y Photosensitive drum 24K, 24C, 24M, 24Y Developing roller 30 Transfer belt 32 Belt drive roller 34 Image memory 38 Fixing roller 42K, 42C, 42M, 42Y Laser diode 50 Paper 60 Control unit 62 Image input unit 64 LSU
66 Drive unit 68 Display unit 70 Operation unit 72 Development unit 74 Fixing unit

Claims (7)

An image forming apparatus comprising: an image forming unit that forms a color image; and a control unit that causes the image forming unit to form an adjustment image when an instruction for forming an adjustment image is received.
The control means is configured to form an adjustment image having an intersecting portion where lines of the same color intersect and an abutting portion against which the tip of a line of a different color is abutted. Image forming apparatus.   The image for adjustment includes a plurality of cross-shaped figures and is arranged so that the ends of the cross-shaped figures of different colors collide with each other, or includes a cross-shaped figure and a straight line of a plurality of colors, and the ends of the cross-shaped figures and straight lines of different colors The image forming apparatus according to claim 1, wherein the image forming apparatus is disposed so as to abut against each other.   3. The image forming apparatus according to claim 1, wherein the adjustment image includes a straight line that is perpendicular to the straight line that is arranged such that a straight line and a tip of the cross-shaped figure abut each other.   The image forming apparatus according to claim 1, wherein the adjustment image includes a bowl-shaped figure or a rice field-shaped figure.   The adjustment image is arranged by arranging four color unit images including a cross figure in two rows and two columns as one block, and arranging a plurality of columns in which a plurality of blocks are arranged alternately by shifting half a block. The image forming apparatus according to claim 2, wherein the image forming apparatus is an image forming apparatus.   6. The image forming apparatus according to claim 1, wherein the adjustment image includes a plurality of cross-shaped figures arranged in a direction perpendicular to a conveyance direction of a sheet on which the adjustment image is formed. .   2. The image forming apparatus according to claim 1, wherein the adjustment image includes a figure in which two quadrangles are arranged so that one diagonal line of each quadrangle is on the same straight line.

Images