JP2006072075A - Image forming apparatus and image forming regulation method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus for matching a front image with a rear image, by simply and in detailed manner of detecting the shift of the front and the rear and make the regulation contents clearer. <P>SOLUTION: The image forming apparatus for forming an image, by transferring a toner image on an image carrier on paper and incorporating a front and rear shift test mode comprises an image forming part for forming a pattern image on the front and rear faces of the paper by generating a test pattern, a pattern-detecting means for detecting the position of the pattern images of the front and rear faces, a shift-detecting means for detecting the pattern image of the paper front and rear detected with the pattern detecting means and the shift of a reference test pattern, and a regulation means for controlling the shift of the paper front and rear so as to cancel it by calculating the regulated amount from the shift detected by the shift-detecting means. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an image forming apparatus and an image formation adjusting method, and more particularly, to an image forming apparatus and an image formation adjusting method capable of eliminating a positional deviation between front and back surfaces in double-sided image formation.

  In an image forming apparatus having a double-sided image forming function, an image is formed with the intention that a predetermined image is formed at the same position on the front surface and the back surface during double-sided image formation. However, contrary to the operator's intention, there are cases where predetermined images are formed at different positions on the front and back surfaces of the recording paper.

In order to eliminate such a deviation, for example, double-sided image formation is performed with measurement position marks at predetermined positions on both sides of the paper, and images are formed with marks on both sides of the paper. Detects the position of double-sided marks from the image data obtained by scanning the detected paper, detects the misalignment of both sides of the detected mark, calculates the adjustment value from the detected misalignment of both sides of the paper, and forms double-sided images An image forming adjustment method for performing control so as to eliminate the positional deviation between the front and back sides of the paper at the time is disclosed (Patent Document 1).
JP 2003-173209 A

  However, it is necessary to prepare a document with a mark in order to detect misregistration, and there is a problem that adjustment is difficult only by misregistration between the front and back surfaces of the paper. Therefore, it is desired that the positional deviation between the front and back surfaces of the paper can be detected more easily, and that the adjustment is simple and the accuracy is high.

  The present invention has been made in view of the above problems, and an object of the present invention is to easily detect in detail the positional deviation of the front and back surfaces of the paper, to make adjustment contents clearer and more accurate, and to ensure that the front and back images are reliably An object of the present invention is to provide an image forming apparatus and an image forming adjustment method capable of matching.

  The object of the present invention can be achieved by any of the following means.

  (1) In an image forming apparatus that transfers a toner image on an image carrier onto a sheet to form an image and also has a built-in misregistration test mode for the front and back sides of the sheet, a test pattern is generated and the pattern image is transferred to the front and back sides of the sheet. An image forming unit to be formed, a pattern image detecting unit for detecting the position of the pattern image on the front and back surfaces, a positional deviation between the pattern images on the front and back surfaces detected by the pattern image detecting unit, A misregistration detecting means for detecting a misregistration of the pattern image, and an adjusting means for calculating an adjustment amount based on the misregistration detected by the misregistration detection means and controlling so as to eliminate the misregistration of the front and back images. An image forming apparatus comprising:

  (2) In an image forming apparatus that transfers a toner image on an image bearing member onto a sheet through an intermediate transfer member to form an image and incorporates a position deviation test mode for the front and back surfaces of the sheet, a test pattern is generated to generate the test pattern. Pattern intermediate image detecting means for detecting the position of the pattern intermediate image transferred to the intermediate transfer member, an image forming unit for generating a test image on the front and back surfaces of the paper by generating a test pattern, and the pattern images on the front and back surfaces A pattern image detecting means for detecting a position, a position deviation detecting means for detecting a position deviation between the front and back pattern images detected by the pattern image detecting means, and a position deviation of the front and back pattern images with respect to the pattern intermediate image; Adjustment means for calculating an adjustment amount based on the positional deviation detected by the positional deviation detection means and controlling so as to eliminate the positional deviation between the front and back images. An image forming apparatus characterized by comprising a.

  (3) The image forming apparatus according to (2), wherein the misregistration detection unit detects misregistration of the pattern images on the front and back surfaces with respect to the test pattern.

  (4) The image according to (1), (2), or (3), wherein the shape given to the test pattern is a shape that overlaps when the paper is turned upside down in a predetermined direction. Forming equipment.

  (5) The image forming apparatus according to (1), (2), (3) or (4), wherein an end portion of the sheet is used as a predetermined reference position of the sheet.

  (6) The pattern image detecting means detects the pattern image on the front surface, inverts the pattern image on the back surface by image processing, and superimposes the pattern image on the front and back surfaces of the paper (1) to ( The image forming apparatus according to any one of 5).

  (7) The image forming apparatus according to any one of (1) to (6), wherein the pattern image detecting unit uses a document reading unit that reads a document provided in the image forming apparatus.

  (8) In an image forming adjustment method of an image forming apparatus incorporating a misregistration test mode for the front and back surfaces of a paper while forming an image by transferring a toner image on an image carrier onto the paper, a pattern image is generated by generating a test pattern. Is detected on the front and back sides of the paper, the position of the pattern images on the front and back sides is detected, and the positional deviation between the detected front and back pattern images and the positional deviation of the pattern image on the front and back sides with respect to the test pattern are detected and detected. An image forming adjustment method, wherein an adjustment amount is calculated based on the misregistration to adjust so as to eliminate the misregistration between the front and back images.

  (9) In an image forming adjustment method of an image forming apparatus having a built-in misregistration test mode on the front and back sides of a sheet, the toner image on the image carrier is transferred to a sheet through an intermediate transfer member to form an image. Detecting the position of the pattern intermediate image transferred to the intermediate transfer body, generating a test pattern to form a pattern image on the front and back surfaces of the paper, detecting the position of the pattern image on the front and back surfaces, Detects the positional deviation between the detected front and back pattern images, the positional deviation of the front and back pattern images with respect to the pattern intermediate image, calculates the adjustment amount based on the detected positional deviation, and calculates the positional deviation of the front and back images. An image forming adjustment method, wherein adjustment is performed so as to eliminate the problem.

  Here, the “positional deviation” means all the positional deviations with respect to the reference, for example, deviations with respect to the reference point, line, or shape.

  Since it comprised as mentioned above, there exist the following effects.

  According to the first and eighth aspects of the present invention, a test pattern is generated to form a pattern image on the front and back sides of the paper, the position of the pattern image on the front and back sides is detected, and the detected pattern images on the front and back sides of the paper and Detects the misalignment of the test pattern, calculates the amount of adjustment from the detected misalignment, and controls to eliminate the misalignment between the front and back sides of the paper. The contents are clearer and can be adjusted with high accuracy, and the front and back images can be reliably matched.

  According to the second and ninth aspects of the invention, a test pattern is generated to detect the position of the pattern intermediate image transferred to the intermediate transfer member, and the test pattern is generated to form the pattern image on the front and back surfaces of the paper. The position of the pattern image on the front and back surfaces is detected, and the position shift between the detected pattern images on the front and back surfaces, the position shift of the pattern image on the front and back surfaces with respect to the pattern intermediate image is detected, and based on the detected position shift Since the adjustment amount is calculated and adjusted so as to eliminate the positional deviation between the front and back images, the positional deviation between the front and back sides of the paper can be detected easily and in detail, the adjustment details can be adjusted more clearly and accurately, and the front and back images can be adjusted. Can be reliably matched.

  According to the third aspect of the present invention, the misalignment detecting means detects misalignment of the pattern images on the front and back surfaces with respect to the test pattern, so that the misalignment between the front and back surfaces can be detected in more detail, and the adjustment content becomes clearer. It was.

  According to the fourth aspect of the present invention, the test pattern is a pattern that overlaps when the paper is reversed in a predetermined reversal direction, so that it is easy to detect the positional deviation between the front and back sides.

  According to the fifth aspect of the invention, since the end portion provided on the sheet is used as the predetermined reference position, the reference position can be easily detected.

  According to the sixth aspect of the invention, the pattern image detecting means detects the pattern image on the front and back surfaces of the paper, inverts the pattern image on the back surface of the paper by image processing, and superimposes the pattern image on the front and back surfaces of the paper. When it is difficult to show the pattern image, it can be surely superimposed.

  According to the seventh aspect of the invention, since the pattern image detecting means uses the original reading means for reading the original provided in the image forming apparatus, the pattern image can be detected easily and reliably.

  An image forming apparatus and an image forming adjustment method in the embodiment will be described. First, the <mechanical configuration of the image forming apparatus> common to the first and second embodiments will be described. FIG. 1 is a diagram illustrating a configuration of an image forming apparatus according to an embodiment.

  As shown in FIG. 1, the image forming apparatus is a tandem type image forming apparatus that forms a color image through an intermediate transfer member, and includes a plurality of sets of image forming units 10Y, 10M, 10C, and 10K, and an intermediate transfer unit. 7 and a paper feeding / conveying section and fixing means 28. An image reading unit SC is disposed on an upper portion of an image forming apparatus main body (hereinafter referred to as an apparatus main body) A.

  The image forming unit 10Y that forms a yellow image includes a charging unit 2Y, an exposure unit 3Y, a developing unit 4Y, a primary transfer unit 5Y, and a cleaning unit 6Y disposed around an image carrier (photoconductor) 1Y. The image forming unit 10M that forms a magenta image includes an image carrier (photoconductor) 1M, a charging unit 2M, an exposure unit 3M, a developing unit 4M, a primary transfer unit 5M, and a cleaning unit 6M. The image forming unit 10C that forms a cyan image includes an image carrier (photoconductor) 1C, a charging unit 2C, an exposure unit 3C, a developing unit 4C, a primary transfer unit 5C, and a cleaning unit 6C. The image forming unit 10K that forms a black image includes an image carrier (photosensitive member) 1K, a charging unit 2K, an exposure unit 3K, a developing unit 4K, a primary transfer unit 5K, and a cleaning unit 6K. Each image forming unit 10 (10Y, 10M, 10C, 10K) is charged, exposed, and developed to form an image of each color on the image carrier 1.

  The intermediate transfer unit 7 includes a semiconductive endless belt-shaped intermediate transfer body 70 that is wound around a plurality of rollers and is rotatably supported.

  The images of the respective colors formed by the image forming units 10Y, 10M, 10C, and 10K are synchronized and sequentially transferred onto the rotating intermediate transfer body 70 by the primary transfer units 5Y, 5M, 5C, and 5K. Thus, a synthesized color image is formed. A recording medium (hereinafter referred to as “paper”) P stored in the paper feeding cassette 20 is fed by a paper feeding means 21, passes through a plurality of intermediate rollers 22 A, 22 B, 22 C, 22 D, and registration rollers 23, and is secondary. The color image is transferred onto the paper P at a time by being conveyed to the transfer means 5A. The sheet P on which the color image has been transferred is subjected to fixing processing by the fixing unit 28, sandwiched between the discharge rollers 25 and placed on the discharge tray 26 outside the apparatus.

  In the case of double-sided copying, color images are collectively transferred to the surface of the paper P, fixed by the fixing means 28, passed through the reverse conveyance path 27, and again through the intermediate roller 22D and the registration roller 23, and then the secondary transfer means. The color image is transferred to the back surface of the paper P at a time. The sheet P on which the color image has been transferred is subjected to fixing processing by the fixing unit 28, sandwiched between the discharge rollers 25 and placed on the discharge tray 26 outside the apparatus.

  On the other hand, after the color image is transferred to the paper P by the secondary transfer means (also referred to as an intermediate transfer roller) 5A, the residual toner is removed by the cleaning means 6A from the intermediate transfer body 70 which has separated the curvature of the paper P.

  During the image forming process, the primary transfer unit 5K is always in pressure contact with the photoreceptor 1K. The other primary transfer units 5Y, 5M, and 5C are in pressure contact with the corresponding photoreceptors 1Y, 1M, and 1C, respectively, only during color image formation. The secondary transfer means 5A is in pressure contact with the intermediate transfer body 70 only when the sheet P passes through the secondary transfer means 5A.

  Here, a test pattern used in the embodiment will be described. FIG. 2 shows a test pattern. Nine crosshairs (marks) are formed on the test pattern TP. Cross lines m1, m2,. m3, cross lines m8, m9, m4 are formed at the center, and cross lines m5, m6, m7 are formed at the rear end side. Since the test pattern TP checks the positional deviation when the front and back sides are overlapped, the crosshairs on the front end side and the crosshairs on the rear end side are symmetrical with respect to the center line L. The sheet front / back reversing mechanism is reversed in the transport direction.

(Embodiment 1)
Next, the <electrical configuration of the image forming apparatus> according to the first embodiment will be described. FIG. 3 is a block diagram showing an electrical configuration in the image forming apparatus according to the first embodiment. As shown in FIG. 3, the overall control unit 9 includes a control unit 9a, an image processing unit 9b, a pattern image detection unit (pattern image detection unit) 9c, a position shift detection unit (position shift detection unit) 9d, and an adjustment unit (adjustment). Means) 9e, test mode selection section 9f, and the like.

  The controller 9a has overall control relating to image formation and a test mode control function. The image processing unit 9b performs image processing. The pattern image detector 9c detects the positions of the pattern images on the front and back surfaces. The misregistration detection unit 9d detects misregistration between the front and back pattern images and the test pattern detected by the pattern image detection unit. The adjustment unit (adjustment unit) 9e calculates an adjustment amount based on the positional deviation and performs control so as to eliminate the positional deviation between the front and back surfaces. The test mode selection unit 9f has a function of selecting a front / back surface displacement detection mode.

  The operation unit 91 can be operated to select a front / back position adjustment mode. The display unit 92 displays the detection result of the positional deviation between the front and back surfaces. The image reading means (scanner) SC reads the pattern images on the front and back sides of the paper. The image forming unit 10 forms a pattern image on the front and back surfaces. The image memory 95 stores the pattern image.

  Here, the display screen that displays the positional deviation between the front and back surfaces will be described. FIG. 4 is a diagram showing an example of a display screen displaying the positional deviation between the front and back surfaces. As shown in FIG. 4, the display screen TS1 displays the positional deviation of the pattern image PDa on the front surface, the pattern image PDb on the back surface, and the test pattern TPS. As the reference position, the end PS of the sheet is used. In the display screen TS1, the vicinity of the nine crosshairs M is enlarged and the interval between the crosshairs M is reduced in order to make it easy to see the front / back position deviation visually.

  A description will be given of the detection result of the positional deviation between the front and back surfaces by the above display method. FIG. 5 is a diagram illustrating an example of the detection result of front / back position deviation. As shown in FIG. 5, in the display screen TS2, the pattern image PDa on the front surface is partially bent from the substantially central portion, and the pattern image PDb on the back surface is also partially bent from the substantially central portion. The test pattern TPS indicates a reference pattern. As shown in FIG. 5, both the front and back surfaces are bent symmetrically with respect to the line, the unbent portion matches the test pattern TPS, and no misalignment occurs at the center of the sheet. In this case, if it has been confirmed in advance that the exposure means has been adjusted correctly, it is considered that the front and back are displaced due to the bending of the fixing roller 24 (FIG. 1). However, the positional deviation between the front and back surfaces has been resolved.

Next, the image forming adjustment method of the present invention will be described with reference to FIGS. 1 and 6 using the image forming apparatus of the embodiment. FIG. 6 is a flowchart of the image formation adjustment method.
Flow F11: The front / back position misalignment test mode is set by the operation unit 91.
Flow F12: A test pattern TP is generated to form a pattern image PDa on the surface of the paper.
Flow F13: Reverse the front and back of the paper.
Flow F14: A test pattern TP is generated to form a pattern image PDb on the back side of the paper.
Flow F15: A pattern image is detected by the image reading means (scanner) SC from the front and back pattern images.
Flow F16: The pattern image positions on the front and back surfaces are detected.
Flow F17: Detects the positional deviation of the pattern image between the front and back surfaces and the pattern image on the front and back surfaces with respect to the test pattern.
Flow F18: An adjustment amount is calculated based on the positional deviation.
Flow F19: Adjust the positional deviation between the front and back surfaces.

  As described above, the test pattern is generated, and the positional deviation of the pattern image between the front and back surfaces and the positional deviation of the pattern image of the front and back surfaces with respect to the test pattern are detected. Based on the detected contents of misalignment with a large amount of information as described above, it is possible to easily determine the cause of misregistration between the front and back sides, perform appropriate and accurate adjustment, and match the front and back images with high accuracy.

(Embodiment 2)
The <Electrical configuration of the image forming apparatus> according to the second embodiment will be described. FIG. 7 is a block diagram showing an electrical configuration in the image forming apparatus according to the second embodiment. Parts that are functionally the same as the electrical configuration of the image forming apparatus according to the first embodiment are given the same reference numerals, and a part of the description is omitted. As shown in FIG. 7, the overall control unit 9 includes a control unit 9a, an image processing unit 9b, a pattern image / pattern intermediate image detection unit (pattern image detection unit, pattern intermediate image detection unit) 9g, and a positional deviation detection unit (position A deviation detection unit) 9d, an adjustment unit (adjustment unit) 9e, a test mode selection unit 9f, and the like.

  The pattern image / pattern intermediate image detector 9g detects the positions of the pattern images on the front and back surfaces and the pattern intermediate image. The positional deviation detection unit 9d detects the positional deviation of the pattern image between the front and rear surfaces, and the positional deviation of the pattern image on the front and rear surfaces with respect to the pattern intermediate image and the test pattern. The pattern intermediate image scanner 93 detects a pattern intermediate image.

  Here, the display screen that displays the positional deviation between the front and back surfaces will be described. FIG. 8 is a diagram showing an example of a display screen displaying the positional deviation between the front and back surfaces. As shown in FIG. 8, the display screen TS3 displays the positional deviation of the pattern image PDa on the front surface, the pattern image PDb on the back surface, the pattern intermediate image PDN, and the test pattern TPS. The edge PS provided on the sheet is used as the reference position. In the display screen, the vicinity of the crosshair M is enlarged and the interval between the crosshairs M is reduced in order to make it easy to see the front-back displacement.

  A description will be given of the detection result of the positional deviation between the front and back surfaces by the above display method. FIG. 9 is a diagram illustrating an example of another front / back position detection result. As shown in FIG. 9, on the display screen TS4, the front surface pattern image PDa is displaced like a parallelogram, and the back surface pattern image PDb is also displaced like a parallelogram. The test pattern TPS shows a state with no positional deviation, and the pattern intermediate image PDN shows a state with a slight positional deviation. Both the front and back surfaces are displaced substantially line-symmetrically, and no misalignment occurs on the front end side of the paper. In this case, it can be seen from the pattern intermediate image PDN that the exposure apparatus is correctly adjusted, and it is considered that the front and back positions are shifted due to the bending of the intermediate transfer roller 5A (FIG. 1), and the bending of the registration roller is corrected. However, the positional deviation between the front and back surfaces was resolved.

Next, the image forming adjustment method of the present invention will be described with reference to FIGS. 1 and 10 using the image forming apparatus of the embodiment. FIG. 10 is a flowchart of another image formation adjustment method.
Flow F21: The front / back position misalignment test mode is set by the operation unit 91.
Flow F22: A test pattern TP is generated to form a pattern intermediate image.
Flow F23: The pattern intermediate image scanner 93 detects the pattern intermediate image PDS.
Flow F24: A test pattern TP is generated to form a pattern image on the surface of the paper.
Flow F25: Reverse the front and back of the paper.
Flow F26: A test pattern is generated to form a pattern image on the back side of the paper.
Flow F27: The pattern image is detected by the image reading means SC.
Flow F28: The position of the pattern image is detected.
Flow F29: Detect a positional deviation of the front and back pattern images with respect to the test pattern and pattern intermediate image.
Flow F30: An adjustment amount is calculated based on the positional deviation.
Flow F31: Adjust the front / back position deviation.

  As described above, the test pattern is generated, and the positional deviation of the pattern image between the front and back sides, and the positional deviation of the pattern image on the front and back sides with respect to the test pattern and the pattern intermediate image are detected. It is possible to detect in detail, and based on the detected content of misalignment with a large amount of information as described above, it is possible to easily determine the cause of misregistration of the front and back, make appropriate and accurate adjustment, and match the front and back images with high accuracy. It becomes possible.

  In the second embodiment, the same applies to the detection of the positional deviation of the pattern images on the front and back surfaces with respect to the test pattern.

  Further, although an example in which nine cross lines are provided as test patterns has been described, the present invention is not limited to this. For example, lines, dots, figures, etc. suitable for adjusting the positions of various mechanisms may be used. good.

  In the embodiment, an example has been described in which the test pattern and the pattern image are superimposed and displayed on the display provided on the operation panel of the image forming apparatus. However, the front and back position shift may be printed. .

  Although the color image forming apparatus has been described as the image forming apparatus, the present invention can be similarly applied to a black and white image forming apparatus or printer.

1 is a diagram illustrating a configuration of an image forming apparatus according to an embodiment. It is a figure which shows a test pattern. FIG. 2 is a block diagram illustrating an electrical configuration in the image forming apparatus according to the first embodiment. It is a figure which shows an example of the display screen which displayed front and back position shift. It is a figure which shows an example of a front-and-back position shift detection result. It is a figure which shows the flowchart of an image formation adjustment method. 6 is a block diagram illustrating an electrical configuration in an image forming apparatus according to Embodiment 2. FIG. It is a figure which shows an example of the display screen which displayed front and back position shift. It is a figure which shows the display screen which shows an example of the other front-and-back position shift detection result. It is a figure which shows the flowchart of another image formation adjustment method.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Image formation part 9b Image processing part 9c Pattern image detection part (pattern image detection means)
9g Pattern image / pattern intermediate image detection unit (pattern image detection means, pattern intermediate image detection means)
9d Position shift detector (position shift detector)
9e Adjustment part (adjustment means)
93 pattern intermediate image scanner SC image reading means (scanner)
TP test pattern PDa surface pattern image PDb back surface pattern image PDN pattern intermediate image

Claims (9)

In an image forming apparatus which transfers a toner image on an image carrier onto a sheet to form an image and incorporates a positional deviation test mode on the front and back sides of the sheet.
An image forming unit for generating a test pattern and forming pattern images on the front and back surfaces of the paper;
Pattern image detection means for detecting the position of the pattern images on the front and back surfaces;
A positional deviation detecting means for detecting a positional deviation between the front and back pattern images detected by the pattern image detecting means, a positional deviation of the front and back pattern images with respect to the test pattern;
Adjusting means for calculating an adjustment amount based on the positional deviation detected by the positional deviation detecting means and controlling so as to eliminate the positional deviation of the front and back images; and
An image forming apparatus comprising: In an image forming apparatus that transfers a toner image on an image carrier onto a sheet through an intermediate transfer member to form an image and incorporates a positional deviation test mode for the front and back surfaces of the sheet.
Pattern intermediate image detection means for generating a test pattern and detecting the position of the pattern intermediate image transferred to the intermediate transfer member;
An image forming unit for generating a test pattern and forming pattern images on the front and back surfaces of the paper;
Pattern image detection means for detecting the position of the pattern images on the front and back surfaces;
A positional deviation detecting means for detecting a positional deviation between the front and back pattern images detected by the pattern image detecting means, a positional deviation of the front and rear pattern images with respect to the pattern intermediate image;
Adjusting means for calculating an adjustment amount based on the positional deviation detected by the positional deviation detecting means and controlling so as to eliminate the positional deviation of the front and back images;
An image forming apparatus comprising: The image forming apparatus according to claim 2, wherein the misregistration detection unit detects misregistration of a pattern image on the front and back surfaces with respect to a test pattern. The image forming apparatus according to claim 1, wherein the shape given to the test pattern is a shape that overlaps when the paper is turned upside down in a predetermined direction. The image forming apparatus according to claim 1, wherein an end portion of the sheet is used as a predetermined reference position of the sheet. 6. The pattern image detecting unit according to claim 1, wherein the pattern image detecting unit detects a pattern image on the front surface, inverts the pattern image on the back surface by image processing, and superimposes the pattern image on the front and back surfaces of the paper. 2. The image forming apparatus according to item 1. The image forming apparatus according to claim 1, wherein the pattern image detecting unit uses a document reading unit configured to read a document provided in the image forming apparatus. In an image forming adjustment method of an image forming apparatus, which includes a toner image on an image carrier transferred to a sheet to form an image and a built-in misregistration test mode for the front and back sides of the sheet.
Generate a test pattern to form pattern images on the front and back of the paper,
Detect the pattern image position on the front and back
Detect the positional deviation between the detected pattern images on the front and back surfaces, the positional deviation of the pattern images on the front and back surfaces with respect to the test pattern,
An image forming adjustment method, characterized in that an adjustment amount is calculated based on the detected misregistration to adjust so as to eliminate misregistration between the front and back images. In an image forming adjustment method of an image forming apparatus that includes a toner image on an image carrier transferred to a sheet via an intermediate transfer member to form an image and a built-in positional deviation test mode for the front and back surfaces of the sheet.
Detecting the position of the pattern intermediate image transferred to the intermediate transfer member by generating a test pattern,
Generate a test pattern to form pattern images on the front and back of the paper,
Detecting the position of the pattern image on the front and back surfaces,
Detects the positional deviation between the detected pattern images on the front and back surfaces, the positional deviation of the pattern images on the front and back surfaces relative to the pattern intermediate image
An image forming adjustment method, characterized in that an adjustment amount is calculated based on the detected misregistration to adjust so as to eliminate misregistration between the front and back images.

Images