JP2005181535A - Image forming apparatus and image forming method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To maintain image quality in accordance with user's demand level and to make the time when an image forming apparatus can not be used because of correction processing as short as possible. <P>SOLUTION: The image forming apparatus includes an image forming means 60, an operation means 16 with a frequency setting function operated to optionally set the performance frequency of the correction processing in the image forming means 60, and a control means 15 for discriminating whether or not the image forming means 60 attains correction time with the performance frequency set by the operation means 16 as reference and also performing the correction processing of the image forming means 60 at the correction time on the basis of the discriminated result. By such constitution, the correction processing of the image forming means 60 is performed at correction performance intervals according to the optionally set performance frequency. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention has an intermediate transfer belt or a transfer material conveyance belt, and a color image forming apparatus and an image suitable for being applied to a tandem type color printer, a color copying machine, a complex machine thereof, etc. that execute a process correction mode The present invention relates to a forming method.

  In recent years, tandem type color printers, color copiers, and multi-function machines of these are often used. In these color image forming apparatuses, yellow (Y), magenta (M), cyan (C), and black (BK) exposure means, developing means, photosensitive drums, and intermediate transfer belts or conveying material transfer belts are used. And a fixing device.

  For example, the Y-color exposure means draws an electrostatic latent image on the photosensitive drum based on arbitrary image information. In the developing device, a color toner image is formed by attaching a Y-color toner to the electrostatic latent image drawn on the photosensitive drum. The photosensitive drum transfers the toner image to the intermediate transfer belt. Similar processing is performed for the other M, C, and BK colors. The color toner image transferred to the intermediate transfer belt is transferred to a sheet and then fixed by a fixing device.

  According to this type of color image forming apparatus, color registration correction, maximum image density (Dmax) correction, and gradation correction are performed for the purpose of maintaining high image quality, but the frequency of executing the correction processing is high. In addition, the time for correction processing tends to be long. As execution conditions for these correction processes, a fixed value is described in a read-only memory (ROM). For example, the correction execution time is written as “1000 sheets”. This means that “when it is time to execute correction” when 1000 sheets have been reached since the start of image formation processing (printing). When this correction execution condition is satisfied after the start of printing, the correction operation is automatically shifted to. The correction execution conditions described in the ROM, such as the execution frequency and the correction execution timing, are often fixed values set at the time of design.

  In a color image forming apparatus, in order to maintain optimum color image formation quality, color misregistration does not occur between Y, M, C, and BK colors that reproduce R, G, and B colors of an original image. It is essential to correct the image forming means (hereinafter referred to as color misregistration correction mode). Color misregistration generally occurs due to assembly tolerances of the image writing unit and the photosensitive drum. Further, it is considered that the exposure means and the support portion such as the photosensitive drum expand and contract due to a change in the outside air temperature due to a change in the outside air temperature or continuous use, causing a positional shift over time, which is considered to be caused by this.

  Regarding the above-described color misregistration correction mode, a registration mark formed on the intermediate transfer belt or the conveyance material transfer belt is detected by a detection unit (hereinafter referred to as a color misregistration detection sensor) for detecting color misregistration such as a reflection type sensor. Deviation amounts of main scanning, sub-scanning, lateral magnification, and skew relating to registration marks of other colors with respect to the reference color are calculated, and color deviation is corrected by adjusting image formation timing and the like.

  In relation to this type of process correction function, Patent Document 1 discloses an image forming apparatus. According to this image forming apparatus, the image forming means is controlled to perform initial setting, laser power adjustment, toner density control, maximum image density correction, gradation correction, and developer preparation using the warm-up time of the fixing device. A control device is provided. When an image forming apparatus is configured with such a control device, a copy image having stable and stable gradation and image density can be obtained without providing a special correction processing time.

  Patent Document 2 discloses an image forming apparatus. According to this image forming apparatus, the fixing operation detection unit and the control unit are provided, and the control unit determines the timing for performing the misalignment correction process based on the operation time of the heater and the like detected by the fixing operation detection unit. Is made. With this configuration, the execution timing of the misregistration correction process can be predicted, and the misregistration correction process can be executed at a low cost and at a timing that improves the image forming efficiency.

Japanese Patent Application Laid-Open No. 08-095460 (2nd page, Fig. 2) JP 2000-228760 A (page 4, Fig. 1)

  However, the conventional tandem type color image forming apparatus has the following problems.

  i. According to the apparatus in which the execution condition of the correction process is described in the ROM or the like as a fixed value, the correction execution time is monitored based on the description content of the ROM, and the correction process is executed when the correction time comes, the correction execution condition is satisfied. Automatically shift to the correction operation. Therefore, once it is shifted to the correction process, it becomes difficult to interrupt the correction process. Therefore, even if the user wants to use the color copying machine or the like, the copying machine or the like is kept until the correction process is completed. Can't use it and waits. As a result, the color copying machine or the like is unusable and productivity may be significantly reduced.

  ii. According to Patent Document 1, initial setting, laser power adjustment, toner density control, maximum image density correction, gradation correction, and developer preparation are performed using the warm-up time. However, when the correction execution time comes in a time zone other than the warm-up time in Patent Document 1, and the user wants to use the color copying machine or the like urgently, the above problem i is not solved and the correction is made. It is expected that the operation time will be longer and the situation where the device cannot be used will become longer.

  iii. According to Japanese Patent Application Laid-Open No. 2004-228620, the timing for performing the misalignment correction process is determined based on the operation time of a heater such as a fixing device. However, in Patent Document 2, when the user wants to use the color copying machine or the like urgently at the execution timing of the predicted misregistration correction process, the above-described problem i is not solved, and the correction operation time becomes long. It is expected that the situation in which the device cannot be used will become long.

  Therefore, the present invention solves the above-described problem, and can maintain an image quality according to a user's requested level and can reduce the time during which the apparatus cannot be used by correction processing as much as possible. An object is to provide a forming apparatus and an image forming method.

  In order to solve the above-described problems, an image forming apparatus according to the present invention is an apparatus that forms an image based on arbitrary image information. The image forming unit and the frequency of execution of correction processing in the image forming unit are arbitrarily set. The frequency setting operation means that is operated to set the correction time, and whether or not the correction time has been reached based on the execution frequency set by the frequency setting operation means, and the correction time based on the determination result And a control means for correcting the image forming means.

  According to the image forming apparatus of the present invention, when an image is formed based on arbitrary image information, the frequency setting operation unit is operated to arbitrarily set the execution frequency of correction processing in the image forming unit. . The image forming unit forms an image based on arbitrary image information. Based on this assumption, the control unit determines whether the correction time has been reached based on the execution frequency set by the frequency setting unit, and corrects the image forming unit at the correction time based on the determination result. Come to process.

  Therefore, the image forming unit can be corrected at a correction execution interval with an execution frequency set arbitrarily. Thus, when the correction execution interval is set to be short according to the user's image quality requirement level, high image quality can always be maintained, and when the correction execution interval is set to be long, the correction process is performed. As a result, the time during which the apparatus cannot be used can be shortened as much as possible.

  An image forming method according to the present invention is a method of forming an image based on arbitrary image information in an image forming system, and sets the execution frequency of correction processing in the image forming system and the correction execution conditions in the correction processing. Determining whether or not the correction time has been reached with reference to a preset execution frequency, and correcting the image forming system based on the correction execution condition at the correction time determined here. is there.

  According to the image forming method of the present invention, when an image based on arbitrary image information is formed in the image forming system, the image forming system is corrected with a correction execution interval and a correction execution condition at an arbitrarily set execution frequency. can do.

  According to the image forming apparatus of the present invention, when an image is formed based on arbitrary image information, it is determined whether or not the correction time has been reached with reference to an execution frequency that is arbitrarily set in advance. Control means for correcting the image forming means at the correction time based on the determination result is provided.

  With this configuration, the image forming unit can be corrected at a correction execution interval with an arbitrarily set execution frequency. Therefore, when the correction execution interval is set to be short according to the image quality requirement level of the user, it is always possible to maintain high image quality, and when the correction execution interval is set to be long, the device is corrected by correction processing. The time when it becomes impossible to use can be shortened as much as possible.

  According to the image forming method of the present invention, the execution frequency of the correction process in the image forming system and the correction execution condition in the correction process are set in advance, and the correction time is reached based on the execution frequency set here. The image forming system is corrected based on the correction execution conditions set in advance at the correction time determined here.

  With this configuration, the image forming unit can be corrected with a correction execution interval and a correction execution condition based on an arbitrarily set execution frequency.

Hereinafter, an image forming apparatus and an image forming method according to embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a conceptual diagram showing a configuration example of a color copying machine 100 as an embodiment of the present invention.
In this embodiment, control means for controlling the formation of an image based on arbitrary image information is provided, and it is determined whether or not the correction time has been reached with reference to an execution frequency arbitrarily set in advance, and the determination result is When the correction execution interval is set to be short according to the user's image quality requirement level, the image forming means is corrected based on the correction time, so that high image quality can be maintained and the correction execution interval is long. When set, the time during which the apparatus cannot be used by the correction process can be shortened as much as possible.

  A color copying machine 100 shown in FIG. 1 is an example of an image forming apparatus, and is an apparatus that forms a color image by superimposing colors on an image forming body based on arbitrary image information. The process correction mode and the color misregistration correction mode are executed. Here, the process correction mode refers to an operation of correcting an image forming process (hereinafter also referred to as an image forming system) in which an image for color adjustment is formed on an image forming body and the image is read to adjust a color image.

  In addition, the color misregistration correction mode is a method of forming an image of each color including a reference color for color misregistration correction on an image forming body, reading the passage timing of the image for color misregistration correction, and other colors for the reference color image. This is an operation for calculating the amount of image displacement and correcting the image forming position based on the amount of displacement.

  The color copying machine 100 includes a copying machine main body 101 and an image reading device 102. An image reading device 102 including an automatic document feeder 201 and a document image scanning exposure device 202 is installed on the upper part of the copying machine main body 101. The document 30 placed on the document table of the automatic document feeder 201 is conveyed by a conveying means, and one or both sides of the document are scanned and exposed by the optical system of the document image scanning exposure device 202 to reflect the document image. Incident light is read by the line image sensor CCD.

  The analog image signal photoelectrically converted by the line image sensor CCD is subjected to analog processing, A / D conversion, shading correction, image compression processing, and the like in an image processing unit (not shown) to become digital image data Din. The image data Din is converted into image data Dy, Dm, Dc, Dk for Y, M, C, BK colors, and then image writing units (exposure means) 3Y, 3M, 3C constituting the 0 image forming means 60. To 3K.

  The automatic document feeder 201 described above is provided with automatic double-sided document conveying means. The automatic document feeder 201 continuously reads the contents of a large number of documents 30 fed from the document placement table at once, and stores the document contents in a storage means (electronic RDH function). This electronic RDH function is conveniently used when copying the contents of a large number of documents by the copying function or when transmitting a large number of documents 30 by the facsimile function.

  The copying machine main body 101 is called a tandem type color copying machine. The image forming means 60 includes a plurality of sets of image forming units (image forming systems) 10Y, 10M, 10C, and 10K each having an image forming body for each color, and an endless intermediate transfer belt (image transfer) as an example of an intermediate transfer body. System) 6, a paper feeding / conveying means including a re-feeding mechanism (ADU mechanism), and a fixing device 17 for fixing the toner image.

  The image forming unit 10Y that forms a yellow (Y) image includes a photosensitive drum 1Y as an image forming body that forms a Y-color toner image, and a Y-color charging disposed around the photosensitive drum 1Y. Means 2Y, exposure means 3Y, developing device 4Y, and image forming body cleaning means 8Y. An image forming unit 10M for forming a magenta (M) color image includes a photosensitive drum 1M as an image forming body for forming an M color toner image, an M color charging unit 2M, an exposure unit 3M, and a developing device 4M. And an image forming member cleaning means 8M.

  An image forming unit 10C for forming a cyan (C) color image includes a photosensitive drum 1C as an image forming body for forming a C toner image, a charging unit 2C for C color, an exposure unit 3C, and a developing device 4C. And an image forming member cleaning means 8C. An image forming unit 10K that forms a black (BK) color image includes a photosensitive drum 1K as an image forming body that forms a BK color toner image, a charging unit 2K for BK color, an exposure unit 3K, and a developing device 4K. And an image forming member cleaning means 8K.

  The charging unit 2Y and the exposure unit 3Y, the charging unit 2M and the exposure unit 3M, the charging unit 2C and the exposure unit 3C, and the charging unit 2K and the exposure unit 3K constitute a latent image forming unit. Development by the developing devices 4Y, 4M, 4C, and 4K is performed by reversal development in which a development bias in which an AC voltage is superimposed on a DC voltage having the same polarity (negative polarity in this embodiment) as the polarity of the toner to be used is applied. . The intermediate transfer belt 6 is wound around a plurality of rollers and is rotatably supported. Each of the Y, M, C, and BK colors formed on each of the photosensitive drums 1Y, 1M, 1C, and 1K. A toner image is transferred.

  Here, an outline of the image forming process will be described below. Each color image formed by the image forming units 10 </ b> Y, 10 </ b> M, 10 </ b> C, and 10 </ b> K is subjected to primary transfer bias (not shown) having a polarity (positive polarity in this embodiment) opposite to the toner to be used. The rollers 7Y, 7M, 7C, and 7K are sequentially transferred (primary transfer) onto the rotating intermediate transfer belt 6 to form a synthesized color image (color image: color toner image). The color image is transferred from the intermediate transfer belt 6 to the paper P.

  The paper P accommodated in the paper cassettes 20A, 20B, and 20C is fed by the feed roller 21 and the paper feed roller 22A provided in the paper cassettes 20A, 20B, and 20C, respectively, and the transport rollers 22B, 22C, 22D, After passing through the registration roller 23 and the like, the sheet is conveyed to the secondary transfer roller 7A, and the color image is collectively transferred to one surface (front surface) on the paper P (secondary transfer).

  The paper P on which the color image has been transferred is fixed by the fixing device 17, is sandwiched between the paper discharge rollers 24, and is placed on a paper discharge tray 25 outside the apparatus. The transfer residual toner remaining on the peripheral surfaces of the photosensitive drums 1Y, 1M, 1C, and 1K after the transfer is cleaned by the image forming body cleaning means 8Y, 8M, 8C, and 8K, and enters the next image forming cycle.

  At the time of double-sided image formation, the paper P formed on one side (front surface) and discharged from the fixing device 17 is branched off from the sheet discharge path by the branching unit 26, and constitutes a sheet feeding and conveying unit. After passing through the circulation sheet passing path 27A, the front and back are reversed by a reversing conveyance path 27B which is a refeed mechanism (ADU mechanism), passes through the refeed conveyance section 27C, and merges at the sheet feeding roller 22D. The reversely conveyed sheet P is conveyed again to the secondary transfer roller 7A through the registration roller 23, and a color image (color toner image) is collectively transferred onto the other side (back side) of the sheet P. The paper P on which the color image has been transferred is fixed by the fixing device 17, is sandwiched between the paper discharge rollers 24, and is placed on a paper discharge tray 25 outside the apparatus. On the other hand, after the color image is transferred to the paper P by the secondary transfer roller 7A, the residual toner is removed by the intermediate transfer belt cleaning means 8A from the intermediate transfer belt 6 that has separated the curvature of the paper P. A temperature sensor (not shown) is provided in the fixing device 17 so as to detect the fixing temperature.

The time of forming these images, 52.3~63.9kg / m ² (1000 sheets) as the paper P about thin and 64.0~81.4kg / m ² (1000 sheets) of approximately plain paper, 83 .0~130.0kg / m ² (1000 sheets) about cardboard and 150.0kg / m ² (1000 sheets) about super thick paper is used. The thickness of the paper P (paper thickness) is about 0.05 to 0.15 mm.

  A temperature sensor 11 is attached inside the copying machine main body 101. For example, the temperature sensor 11 is installed in the vicinity of the intermediate transfer belt 6. The temperature sensor 11 detects an in-machine temperature such as the temperature of the intermediate transfer belt 6 and outputs a temperature detection signal S1. The temperature sensor 11 has a thermocouple structure, a thermistor structure, or an IC thermocouple structure.

  A color misregistration detection sensor 12 as an example of a detection unit is provided on the upstream side of the cleaning unit 8A and on the left side of the intermediate transfer belt 6, and the image forming units 10Y, 10M, and 10C described above. The position of a color image (hereinafter referred to as a registration mark) including a reference color for color misregistration correction formed on the intermediate transfer belt 6 by 10K is detected and a position detection signal S2 is output. A density detection sensor 13 is provided on the downstream side of the color misregistration detection sensor 12, and detects the density of the reference patch image and outputs a density detection signal S3.

  The copying machine main body 101 is provided with a control unit 15 and executes a process correction mode and a color misregistration correction mode at the correction time. This process correction mode includes a surface potential correction process, a maximum image density correction process (Dmax correction), and a gradation correction process. In the surface potential correction process, a correction operation is performed to keep the surface potential of the photosensitive drums 1Y, 1M, 1C, and 1K constant. In the maximum image density correction process, a correction operation is performed to keep the maximum image density constant in the developing devices 4Y, 4M, 4C, and 4K. In the gradation correction process, the image processing means 70 executes a γ correction operation that keeps the gradation constant from the highlight to the maximum image density. In the process correction operation, the photoreceptor surface potential correction, the maximum image density correction, and the gradation correction are executed in one set.

  When the color misregistration correction mode is executed, the image writing start position of the laser beam with respect to the photosensitive drums 1Y, 1M, 1C, and 1K is adjusted. For example, in the color misregistration correction mode, a registration mark for color misregistration correction is formed on the intermediate transfer belt 6, the passage timing of the registration mark is read, and another registration mark position (edge, center of gravity, etc.) for the reference color is read. The positional deviation amount of the color registration mark is calculated, and the image forming position at the time of color superposition is corrected based on the positional deviation amount. Here, the image forming position at the time of color superposition refers to toner images of Y color, M color, C color, BK color, etc., when an arbitrary color image based on color image data is reproduced on the intermediate transfer belt 6. Is the position to overlap. This image forming position is corrected by adjusting the image writing start position for the photosensitive drums 1Y, 1M, 1C, and 1K.

  FIG. 2 is a block diagram illustrating a configuration example of a control system of the color copying machine 100. 2 includes a temperature sensor 11, a color misregistration detection sensor 12, a density sensor 13, a control unit 15, a communication unit 19, a paper feeding unit 20, an image memory 33, an operation panel 48, an image forming unit 60, The image processing unit 70 and the image reading device 102 are included.

  The image reading apparatus 102 is connected to the control means 15 and reads an image from the original 30 shown in FIG. 1 and outputs digital image data Din to the image memory 33. The image memory 33 stores the image data Din input from the image reading apparatus 102. The image processing unit 70 performs image processing on the image data Din read from the image memory 33 and transfers the image data Dout after the image processing to the image memory 33 or the image forming unit 60. The image forming unit 60 includes the image forming units 10Y, 10M, 10C, and 10K shown in FIG. The above-described image data Dout is converted into image data Dy, Dm, Dc, Dk for Y, M, C, K colors, and then image writing units (exposure means) 3Y, 3M, Sent to 3C, 3K.

  The temperature sensor 11 is connected to the control means 15, detects the temperature inside the copying machine main body 101, and outputs a temperature detection signal S 1 to the control means 15. The control means 15 executes the process correction mode based on the temperature detection information after the temperature detection signal S1 is converted from analog to digital. The color misregistration detection sensor 12 detects color misregistration such as a color resist image formed on the intermediate transfer belt 6 and outputs a color misregistration detection signal S <b> 2 to the control unit 15. The control unit 15 performs color misregistration correction based on position detection information after the color misregistration detection signal S2 is converted from analog to digital.

  The density sensor 13 detects the density of a reference patch image or the like formed on the intermediate transfer belt 6 and outputs a density detection signal S3 to the control unit 15. The control means 15 adjusts the toner density and the like based on density detection information after the density detection signal S3 is converted from analog to digital.

  The control means 15 includes a nonvolatile memory 14, a correction amount calculation unit 51, a system bus 55, an interface 56, a CPU (Central Processing Unit) 57, a ROM (Read Only Memory) 58, and a work RAM (Random Access Memory). 59). The system bus 55 is connected to the interface 56. Although not shown, the sensors 11 to 13, the image memory 33, the communication unit 19, the paper feeding unit 20, the operation panel 48, the image forming unit 60, the image processing unit 70, and the image reading apparatus 102 are connected to the interface 56.

  The system bus 55 connected to the interface 56 is connected to the nonvolatile memory 14, the correction amount calculation unit 51, the CPU 57, the ROM 58, and the work RAM 59. The ROM 58 stores system program data for controlling the entire copying machine. The RAM 59 temporarily stores control commands when various modes are executed. When the power is turned on, the CPU 57 reads the system program data from the ROM 58, starts up the system, and controls the entire copying machine. The CPU 57 adjusts the Y color, M color, and C color writing timing, the CLK frequency, the horizontal and vertical inclinations, and the like according to the correction amount of each error factor.

  The nonvolatile memory 14 is an example of a storage unit, and stores information related to the date and time when the image forming unit 60 was corrected last time (hereinafter referred to as corrected date and time data). In addition to the correction date and time data, the non-volatile memory 14 records position detection information after the A / D conversion and binarization of the position detection signal S2 output from the color shift detection sensor 12 in the color shift correction mode. The In addition to the position detection information, the non-volatile memory 14 also stores data relating to the amount of misregistration and the amount of color misregistration.

  The correction amount calculation unit 51 described above performs main scanning correction amount calculation processing, sub-scanning correction amount calculation processing, overall horizontal magnification correction amount calculation processing, partial horizontal magnification correction amount calculation processing, and skew correction amount calculation processing. For example, the correction amount calculation unit 51 reads position detection information from the nonvolatile memory 14 in the color misregistration correction mode, and the amount of deviation of each error factor (main scanning, overall magnification, partial horizontal magnification, skew) is calculated from this position detection information. The correction amount for each error factor is obtained from the calculated shift amount.

  For example, in the main scanning correction amount calculation process, the position detection information is read from the nonvolatile memory 14 and the positional deviation amount in the main scanning direction is calculated. This is for adjusting the writing start timing in the main scanning direction so as to eliminate the positional deviation amount. In the sub-scanning correction amount calculation process, the position detection information is read from the nonvolatile memory 14 and the position shift amount in the sub-scanning direction is calculated. This is for adjusting the writing start timing in the sub-scanning direction so as to eliminate the positional deviation amount.

  In the overall lateral magnification correction amount calculation process, the position detection information is read from the nonvolatile memory 14 and the overall lateral magnification deviation amount is calculated. This is for adjusting the frequency of the pixel clock signal so as to eliminate the overall lateral deviation. In the partial lateral magnification correction amount calculation process, the position detection information is read from the nonvolatile memory 14 and the partial lateral magnification deviation amount is calculated. This is for adjusting the horizontal inclination of the image writing unit 3Y and the like so as to eliminate the partial lateral double shift amount. In the skew correction amount calculation process, the position detection information is read from the nonvolatile memory 14 to calculate the skew deviation amount. This is for adjusting the vertical inclination of the image writing unit 3Y or the like so as to eliminate the skew deviation amount.

  The operation panel 48 is connected to the control means 15 and has an operation means 16 constituted by a touch panel and a display means 18 constituted by a liquid crystal display panel. The operation panel 48 uses GUI (Graphic User Interface) type input means. A power switch (such as a power save button) is provided on the operation panel 48. The display unit 18 performs a display operation in conjunction with the operation unit 16. The operation panel 48 is operated when selecting image forming conditions and the paper feed cassettes 20A to 20C.

  In this example, the operation unit 16 includes a frequency setting unit 16A, a condition setting unit 16B, a stop instruction unit 16C, a confirmation unit 16D, and an execution instruction unit 16E. The frequency setting unit 16A is an example of a frequency setting operation unit, and is operated to arbitrarily set the execution frequency of correction processing in the image forming unit 60. Here, the execution frequency refers to the degree to which correction processing is repeatedly executed at the same correction execution interval. In this example, Table 1 shows an example of the relationship between the correction execution interval setting value and the number of prints.

  According to Table 1, the number of prints = 1000 is set for the correction execution interval setting value # 1. Similarly, the number of prints = 2500 is set for the set value # 2, the number of prints = 5000 is set for the set value # 3, and the number of prints = 7500 for the set value # 4. Sheets are set, and the number of prints = 10000 is set for the set value # 5. The relationship data of the set value versus the number of prints is stored in the nonvolatile memory 14.

  The condition setting unit 16B is an example of a condition setting operation unit, and is operated to set a correction execution condition in the image forming unit 60. By this setting operation, the conditions for shifting to the correction process, that is, the execution frequency and the correction execution timing are freely set and can be freely changed. The stop instruction unit 16C is an example of a stop instruction operation unit, and is manually operated to instruct to stop the correction process (process correction mode) in the image forming unit 60. Since the stop instruction unit 16C can input a request to stop the correction process in the middle of the image forming unit 60, even when the process has already shifted to the correction process, the correction process is forcibly stopped. Can do. Accordingly, the copying machine 100 can be used immediately.

  The confirmation unit 16D is an example of a confirmation operation unit, and is operated so as to confirm whether or not the execution of correction processing in the image forming unit 60 is necessary. For example, when the correction time has come and the correction process is being executed, when the stop instruction unit 16C is operated to instruct the stop of the correction process in the image forming means 60, the correction process is actually performed on the correction process execution necessity confirmation screen P2. Whether or not to stop can be selected by “Yes / No”. The execution instruction unit 16E is an example of an execution instruction operation unit, and is operated to instruct the forced execution of the correction process in the image forming unit 60. This is because the image forming unit 60 is forced to shift to the correction process at any time regardless of the correction time. In this way, the correction process in the image forming unit 60 can be executed even before or after the correction time.

  It should be noted that the image forming conditions and paper feed cassette selection information set by the operating means 16 and the execution frequency, correction execution conditions, correction processing stop, necessity of continuing correction processing, and forced execution instructions for correction processing are related. The information is output to the CPU 57 as operation data D3.

  In addition to the operation means 16 described above, the display means 18 connected to the control means 15 displays the previous correction date and time read from the nonvolatile memory 14 or the elapsed time from the previous correction time to the present time. . The correction date and time, the elapsed time, and the like are supplied from the control means 15 to the display means 18 as display data D2.

  Further, the display unit 18 operates to display a menu selection screen (not shown), a correction processing execution necessity confirmation screen P2 as shown in FIG. 5 and the like based on the display data D2. When the correction is interrupted, the user is warned by informing the user of the date and time when the previous correction was performed and the elapsed time from the previous correction time to the present time. Of course, the display means 18 operates to input image forming conditions on the basic setting screen or the like.

  The control unit 15 determines whether or not the correction time has been reached based on the execution frequency set by the frequency setting unit 16A of the operation unit 16, and based on the determination result, the image is displayed at the correction time. The forming means 60 is corrected. For example, the control unit 15 controls the timing of shifting to the correction process according to preset execution frequency information and the like, and the image forming unit at the correction timing based on the correction execution condition set in advance by the condition setting unit 16B. 60 is corrected.

  Furthermore, when the correction process is interrupted (stopped) in the middle, the control unit 15 prompts the operation of the condition setting operation unit 16 for the next correction execution condition, and a new correction different from the previously set correction execution condition. It is controlled to input execution conditions. The nonvolatile memory 14 stores a correction execution condition that is different from the previously set correction execution condition. The correction execution condition includes a timing for shifting to the correction processing at a timing different from the previous time.

  The communication means 19 is connected to a communication line such as a LAN, and is used when performing communication processing with an external computer or the like. When the color copying machine 100 is used as a printer, the communication means 19 is used to receive print data Din from an external computer in the print operation mode. The paper feeding means 20 is connected to a motor (not shown) for driving the paper feeding cassettes 20A to 20C, controls the rotation of the motor based on the paper feeding control signal S4, and from the paper feeding cassettes 20A, 20B or 20C. It operates so as to convey the fed paper P to the image forming system. The paper feed control signal S4 is supplied from the control means 15 to the paper feed means 20.

FIGS. 3A and 3B are conceptual diagrams showing a configuration example of the operation panel 48 and a display example of the correction timing setting screen P0.
The operation panel 48 shown in FIG. 3A includes a display means 18, a power save button B1, a stop / clear button B2, a start button B3, a numeric keypad B4, and the like. The stop / clear button B2 constitutes the stop instruction unit 16C, and is pressed when canceling the image forming job or interrupting the correction process.

  The correction timing setting screen P0 shown in FIG. 3B transitions from the key operator screen or the like during initial setting, for example. For example, it is displayed on the display means 18 after selecting “Set correction execution condition” on a menu screen (not shown). The correction timing setting screen P0 includes, for example, a message area AR1 and a status icon display area AR2.

  In the message area AR1, character information of “correction execution timing setting” is displayed. In this example, “1” to “5” can be set. The smaller the number, the shorter the interval for shifting to correction, and the higher the image quality. On the contrary, the larger the number, the longer the interval for shifting to correction, and the frequency with which the machine cannot be used due to correction is less, but the image quality may gradually deteriorate.

  For example, in the status icon display area AR2, five selection buttons B # 1 to B # 5 constituting the frequency setting unit 16A are displayed together with character information of “correction execution interval”. The selection button B # 1 corresponds to the correction execution interval setting value # 1 shown in Table 1, and is pressed when setting the number of prints = 1000.

  Similarly, the selection button B # 2 corresponds to the setting value # 2 of the correction execution interval, and is pressed when setting the number of prints = 2500. The selection button B # 3 corresponds to the correction execution interval setting value # 3, and is pressed when setting the number of prints = 5000. The selection button B # 4 is set to the correction execution interval setting value # 4. The selection button B # 5 corresponds to the setting value # 5 of the correction execution interval, and is pressed when setting the number of prints = 10000. Is done. The operation data D3 accompanying the pressing operation of these five selection buttons B # 1 to B # 5 is output to the control means 15. In the figure, the shaded portion is the pressed portion, and the display color is changed.

  The control means 15 shown in FIG. 2 reads the number of prints corresponding to the set value # 1, # 2, # 3, # 4 or # 5 from the nonvolatile memory 14 based on the operation data D3. Is set as a comparison reference value (threshold value) of the counter in a register or the like. Further, a leftward Δ mark is displayed below the selection button B # 1 shown in FIG. 3, and “short” character information is displayed. Below the selection button B # 5 on the opposite side, a rightward Δ mark is displayed and “long” character information is displayed. The “short” indicates “the correction execution interval is short”, and the “long” indicates “the correction execution interval is long”. In this example, when the selection button B # 3 is pressed and “# 3” is set as the correction execution interval, the control unit 15 causes the image forming unit 60 to execute the correction process for every 5000 prints. Control.

  Below these “long” and “short” display areas, three condition setting buttons B5 to B7 constituting the condition setting unit 16B are displayed together with character information of “correction execution permission timing”. The condition setting button B5 is pressed when accepting the selection of “when printing starts” as the correction execution permission timing, and the condition setting button B6 is pressed when accepting the selection of “printing” as the timing, and the condition setting The button B7 is pressed when accepting the selection “after printing” as the timing.

  In this example, all of “at the start of printing”, “during printing”, and “after printing” can be permitted, or not permitted. If all of them are not permitted, correction processing is executed at execution timings other than these three, for example, during warming up or when the operation is not performed for a fixed time and an auto reset is applied. In this example, even if the correction timing (execution timing) is reached, if the timing is not permitted, the correction processing is not executed and is later performed.

  Below the display area such as “when printing starts”, “during printing”, “after printing”, etc., together with the character information of “correction forced execution reservation”, one correction reservation button constituting the execution instruction section 16E B8 is displayed. The correction reservation button B8 is pressed when the image quality deteriorates because the correction process has not been executed for a long time. The user consciously reserves correction on the correction execution timing setting screen P0 by operating the correction reservation button B8, and the control unit 15 can forcibly execute the correction process. In this example, when the correction reservation button B8 is selected on the correction timing setting screen P0 before or after the arrival of the correction time, the setting screen P0 returns to the basic setting screen P1 and correction processing is performed. It is forcibly executed. Note that the buttons B # 3, B6, B7, and B8, including the button B # 3 whose display color is changing, have already been selected as correction execution conditions.

  FIG. 4 is an image diagram showing a display example of the basic setting screen P1 on the display means 18. As shown in FIG. The basic setting screen P1 shown in FIG. 4 is displayed on the display means 18 following a menu screen (not shown) after the power is turned on. In addition to the message area AR1 and the status icon display area AR2, the basic setting screen P1 includes a number display area AR3, various icon display areas AR4, a remaining memory area AR5, a folder button area AR6, and a screen setting display area AR7. .

  In the message area AR1, character information such as “copy reservation is possible” is displayed. An “application setting” icon is displayed in the screen setting display area AR7. The “applied setting” icon is provided with keys K1 to K5 such as “image quality adjustment”, “original setting”, “applied function”, “automatic image rotation cancellation”, “original reading”, and the like. The user can select various keys K1 to K5 from the “application setting” icon at the time of copy reservation.

  FIG. 5 is an image diagram showing a display example of the correction processing execution necessity confirmation screen P2. The correction processing execution necessity confirmation screen P2 shown in FIG. 13 is displayed as a pop-up on the basic setting screen P1. For example, when the stop / clear button B2 shown in FIG. 3 is pressed during the execution of the correction process, the screen P2 instructs the control unit 15 to interrupt the correction process and confirms whether or not the execution is necessary. Is displayed on the display means 18.

The correction processing execution necessity confirmation screen P2 displays the elapsed time and the hour and minute at the time of the previous correction as a guide for the correction processing together with the character information “Do you want to stop the correction?”. This is for prompting the user to determine the necessity of the correction processing and the execution determination thereof.
In this example, character information such as “previous correction is 2/16 10:00” and “30 hours have passed since the previous correction” is displayed. Regarding the elapsed time, it includes the case where the actual time elapsed and the accumulated operating time elapsed are displayed. For example, “3 hours have passed since the previous correction” is displayed for the cumulative operating time, and “30 hours have passed since the previous correction” is displayed for the actual time. The former is the case where the sleeping time is excluded, and the latter is the case including the sleeping time.

  Below these character information display areas, a “YES” key K6 and a “NO” key K7 constituting the confirmation unit 16D are displayed. The “YES” key K6 is pressed when instructing to interrupt the correction process. The “NO” key K7 is pressed when not instructing to interrupt the correction process. When this screen P2 is displayed on the display means 18, the user presses the “YES” key K6 or the “NO” key K7. For example, when the “YES” key K6 is selected, the correction process is interrupted on the spot, and the copying machine 100 returns to a state where it can be copied. When the “NO” key K7 is selected, the correction process is continued as it is.

6A and 6B are time charts showing examples of correction execution in the color copying machine 100. FIG. 6A and 6B, the horizontal axis represents time t.
According to the first correction execution example shown in FIG. 6A, when the set value # 1 is set as the correction execution interval and “after printing” is set as the correction execution permission timing, the control means 15 The correction process is executed as follows. In the drawing, the “correction” portion indicated by hatching indicates the correction execution period. In this example, regarding an image forming job (hereinafter referred to as JOB), JOB1 is 1500 sheets, JOB2 is 250 sheets, JOB2 is 250 sheets, and JOB4 is 1000 sheets.

  In this example, since the set value # 1 is set for the correction execution interval, the correction execution time comes at the time t1 of image formation for 1000 prints indicated by black marks in the drawing. Since “after printing” is set, the correction processing is executed at the time point t2 indicated by the white triangle Δ after the completion of 1500 sheets of image forming processing (printing operation). In this example, the counter is reset when the correction process is completed.

  Thereafter, the image forming process of JOB2 = 250 sheets and JOB2 = 250 sheets is continuously executed, and further, the image forming process of JOB4 = 1000 sheets is executed. At this time, the correction execution timing comes at the image formation time t3 of 500 sheets related to JOB4 indicated by the next black mark Δ in the figure, but “after printing” is set as the correction execution permission timing. In the middle, the correction process is prohibited and cannot be performed, and the correction process is executed at the time t4 indicated by the white mark Δ after the completion of the 1000 image forming jobs related to JOB4.

  Further, according to the second correction execution example shown in FIG. 6B, the set value # 1 is set as the correction execution interval, “printing” and “after printing” are set as the correction execution permission timing, and the correction is performed. When the execution stop instruction operation is performed, the control unit 15 executes the correction process as follows. In the drawing, the “correction” portion indicated by hatching indicates the correction execution period. In this example, for an image forming job, JOB1 is 1500 sheets and JOB2 is 1500 sheets.

  In this example, since the set value # 1 is set for the correction execution interval, the correction process is executed at the image formation time point (time indicated by a white triangle in the figure) t11 of 1000 prints related to JOB1. Thereafter, the remaining 500 image forming processes are continuously executed. Then, based on the setting “after printing”, the correction process is executed at time t12 shown by a white triangle Δ in the drawing. Also in this example, the counter is reset when the correction process is completed.

  Thereafter, the image forming process of JOB2 = 1500 sheets is continuously executed. At this time, the correction execution timing comes at the image formation time t13 of 1000 sheets related to JOB4. However, the correction execution stop (correction cancellation) is performed in the middle of executing the correction process because the user desires to acquire the image formed product as soon as possible. When the operation is performed, the control unit 15 interrupts the correction process, and the remaining 500 image forming processes are continuously performed.

  Then, at the time t14 when all 1500 image forming jobs related to JOB2 are completed, the control unit 15 executes the correction process. In this example, when the correction is canceled, the number of prints from the time t13 when the correction is canceled until the next correction processing is executed may be set separately from the previous setting. For example, if the remaining number is 500, the correction execution timing may be set here.

  Next, the image forming method according to the present invention will be described in two parts: an image forming process / correction condition setting process example and a correction execution determination process example. FIG. 7 is a flowchart showing an example of image forming processing and correction condition setting processing in the color copying machine 100.

  In this embodiment, it is assumed that an image based on arbitrary image information is formed in the image forming system. With regard to the correction condition setting process, a case where the execution frequency of the correction process in the image forming system and the correction execution condition in the correction process are set will be described as an example.

  Using these as image forming conditions, the control unit 15 waits for an image forming request or a correction execution condition setting request while monitoring the detection of the power-on information in step A1 of the flowchart shown in FIG. The operation panel 48 shown in FIG. 3 is provided with a power save button B1. For example, power-on information is generated by pressing the power save button B1 of the copier 100 in the sleeping state. The power-on information becomes operation data D3 and is output from the operation means 16 to the control means 15.

  When the power-on information is detected, the process proceeds to step A2, and the control unit 15 displays character information and the like for selecting an image forming mode or a correction condition setting mode on a menu screen (not shown). At this time, the user selects either the image forming mode or the correction condition setting mode displayed on the menu screen.

  In step A3, the control unit 15 branches the control based on the image forming mode or the correction condition setting mode selected by the user. When the image forming mode is selected, the basic setting screen P1 shown in FIG. The control means 15 sets the image forming conditions input using the operation panel 48 in step A4 in the image forming means 60 and the like.

  At this time, character information such as “Can make a copy reservation” is displayed on the basic setting screen P1 shown in FIG. An “application setting” icon is displayed in the screen setting display area AR7. The “applied setting” icon is provided with keys K1 to K5 such as “image quality adjustment”, “original setting”, “applied function”, “automatic image rotation cancellation”, “original reading”, and the like. The user can select various keys K1 to K5 from the “application setting” icon at the time of copy reservation.

  Thereafter, the process proceeds to step A5, where the control unit 15 controls the image reading apparatus 102 to execute the document image reading process. At this time, the image reading apparatus 102 reads an image from the document 30 shown in FIG. 1 and outputs digital image data Din to the image memory 33. The image processing unit 70 performs image processing on the image data Din read from the image memory 33 and transfers the image data Dy, Dm, Dc, Dk for Y, M, C, and K colors after the image processing to the image forming unit 60. Is done.

  In step A6, the control unit 15 controls the image forming unit 60 to execute image forming processing. At this time, the image forming unit 10Y shown in FIG. 1 forms a Y color image on the photosensitive drum 1Y based on the Y color image data Dy. The image forming unit 10M forms an M color image on the photosensitive drum 1M based on the M color image data Dm. The image forming unit 10C forms a C color image on the photosensitive drum 1C based on the C color image data Dc.

  The image forming unit 10K forms a BK color image on the photosensitive drum 1K based on the BK color image data Dk. Each color image formed on the photosensitive drums 1 </ b> Y to 1 </ b> K is transferred to the intermediate transfer belt 6. The color image transferred to the intermediate transfer belt 6 is transferred to a predetermined paper P fed out from the paper feed cassette, fixed by the fixing device 17 and then discharged.

  In step A7, the control unit 15 determines whether or not the page related to the image forming process is the last page. If the page related to the image forming process is not the final page, the process returns to step A6 and the image forming process is repeated. When the page related to the image forming process is the last page, the process proceeds to step A13. The number of formed images (number of printed sheets) is counted by a counter.

  If the correction condition setting mode is selected in step A3, the process proceeds to step A8. In step A8, the control means 15 controls the display means 18 to display the correction execution timing setting screen P0. At this time, the text information “Correction execution timing setting” is displayed on the correction timing setting screen P0 shown in FIG. 3B. In this example, together with the character information of “correction execution interval”, five selection buttons B # 1 to B # 5 constituting the frequency setting unit 16A are displayed.

  Furthermore, a leftward Δ mark is displayed below the selection button B # 1 shown in FIG. 3B, and “short” character information is displayed. Below the selection button B # 5 on the opposite side, a rightward Δ mark is displayed and “long” character information is displayed. Below these “long” and “short” display areas, three condition setting buttons B5 to B7 constituting the condition setting unit 16B are displayed together with character information of “correction execution permission timing”. Below the display area of these condition setting buttons B5 to B7, etc., one correction reservation button B8 constituting the execution instruction section 16E is displayed together with the character information of “correction forced execution reservation”. In the example shown in FIG. 6A, the set value # 1 relating to 1000 prints is set, and “after printing” is set as the correction execution permission timing.

  Thereafter, the process proceeds to step A9, where the control unit 15 branches the control depending on either the correction condition setting or the correction forced execution reservation. When the correction condition setting is selected, the process proceeds to step A10, and the control means 15 performs the correction execution condition setting process in the process correction mode. At this time, the selection button B # 1 corresponds to the correction execution interval setting value # 1 shown in Table 1 and is pressed when setting the number of prints = 1000.

  Similarly, the selection button B # 2 corresponds to the setting value # 2 of the correction execution interval, and is pressed when setting the number of prints = 2500. The selection button B # 3 corresponds to the correction execution interval setting value # 3, and is pressed when setting the number of prints = 5000. The selection button B # 4 is set to the correction execution interval setting value # 4. The selection button B # 5 corresponds to the setting value # 5 of the correction execution interval, and is pressed when setting the number of prints = 10000. Is done.

  The operation data D3 accompanying the pressing operation of these five selection buttons B # 1 to B # 5 is output to the control means 15. In the figure, the shaded portion is the pressed portion, and the display color is changed. Based on the operation data D3, the control unit 15 reads the number of prints corresponding to the set value # 1, # 2, # 3, # 4 or # 5 from the nonvolatile memory 14, and the number of prints is stored in the counter. It is set in a register or the like as a comparison reference value (threshold value).

  The condition setting button B5 is pressed when accepting the selection of “when printing starts” as the correction execution permission timing, and the condition setting button B6 is pressed when accepting the selection of “printing” as the timing, The condition setting button B7 is pressed when accepting the selection “after printing” as the timing.

  Thereafter, the process proceeds to step A11, and the control means 15 determines whether or not the setting of the correction execution condition is completed. If the correction execution condition has not been set, the process returns to step A10 to continue the correction execution condition setting process. When the correction execution condition has been set, the process proceeds to step A13.

  When the correction forced execution reservation displayed on the correction timing setting screen P0 is selected in step A8, the process proceeds to step A12 and the control means 15 forcibly executes the correction process. At this time, the operation data D3 related to the correction forced execution reservation is output from the operation means 16 to the control means 15 and set in a register or the like. The control means 15 performs a correction process based on the operation data D3 set in the register or the like. In this example, when the correction reservation button B8 is selected on the correction timing setting screen P0, the setting screen P0 returns to the basic setting screen P1 and the correction processing is forcibly executed. After this correction process, the process proceeds to step A13.

  In step A13, the control unit 15 determines whether to end the image forming process. For example, the control unit 15 detects the power-off information and ends the image forming process. If the power-off information is not detected, the process returns to step A1 and the above-described processing is repeated.

  FIG. 8 is a flowchart showing an example of correction execution determination processing in the control means 15. In this embodiment, regarding the execution determination process, it is determined whether or not the correction time has been reached based on a preset execution frequency, and the image forming system is determined based on the correction execution condition at the correction time determined here. It is assumed that the correction is made.

  Under these correction execution determination conditions, the control means 15 determines whether or not the correction execution time has come in step E1 of the flowchart shown in FIG. At this time, the control means 15 determines whether or not the correction time has been reached based on the execution frequency set by the frequency setting unit 16A. For example, the control means 15 compares the preset comparison reference value (threshold value) with the printed sheet count value of the counter and detects whether or not they match, thereby determining whether or not the correction execution time has come. Is determined. In the example shown in FIG. 6A, the set value # 1 for 1000 prints is the comparison reference value. The correction execution permission timing is “after printing”.

  If the correction execution time has not arrived, the process proceeds to step E2 to determine whether or not a correction forcible execution reservation is set. At this time, the control means 15 determines based on whether or not the operation data D3 related to the correction forced execution reservation is set in the register or the like. If the correction forcible execution reservation is not set, the process returns to step E1 to continue monitoring whether the correction execution time has come.

  When the correction execution time has arrived, the process proceeds to step E3, where the control means 15 determines whether it is time to execute the correction process. At this time, whether or not the printing process has been completed is compared based on a preset “after printing”, for example, when the last page and the page related to the image forming process match. It is determined that “printing has ended”, and then it is time to execute the correction process.

  In step E4, the control unit 15 starts correction processing and executes a process correction mode and a color misregistration correction mode. This process correction mode includes a surface potential correction process, a maximum image density correction process (Dmax correction), and a gradation correction process. In the surface potential correction process, a correction operation is performed to keep the surface potential of the photosensitive drums 1Y, 1M, 1C, and 1K constant. In the maximum image density correction process, a correction operation is performed to keep the maximum image density constant in the developing devices 4Y, 4M, 4C, and 4K. In the gradation correction process, the image processing means 70 performs a correction operation for keeping the gradation constant from the highlight to the maximum image density. In the process correction operation, the photoreceptor surface potential correction, the maximum image density correction, and the gradation correction are executed in one set.

  In the color misregistration correction mode, the image writing start position of the laser beam with respect to the photosensitive drums 1Y, 1M, 1C, and 1K is adjusted. For example, in the color misregistration correction mode, a registration mark for color misregistration correction is formed on the intermediate transfer belt 6, the passage timing of the registration mark is read, and another registration mark position (edge, center of gravity, etc.) for the reference color is read. The positional deviation amount of the color registration mark is calculated, and the image forming position at the time of color superposition is corrected based on the positional deviation amount. This image forming position is corrected by adjusting the image writing start position for the photosensitive drums 1Y, 1M, 1C, and 1K.

  In step E5, the control means 15 accepts a correction stop request during execution of the correction process. At this time, the control unit 15 monitors whether or not the stop / clear button B2 of the operation panel 48 constituting the stop instruction unit 16C has been pressed. If there is no correction stop request during monitoring of the stop / clear button B2, the process proceeds to step E6, and the control means 15 determines whether or not to end the correction process. At this time, by receiving a notification of completion of the process correction mode from the image forming unit 60, the control unit 15 determines whether or not the correction process has been completed.

  When the correction process in the image forming unit 60 is completed, the process proceeds to step E7, where the control unit 15 sets the next correction execution time based on a preset correction execution interval. At this time, the value of the counter that counts the number of printed sheets from the previous time until the correction time is cleared.

  If there is a correction stop request in step E5 described above, the process proceeds to step E8, where the control means 15 displays a correction process execution necessity confirmation screen P2 and confirms the stop of the correction process. The At this time, the confirmation unit 16D of the operation unit 16 is operated to confirm whether or not the execution of correction processing in the image forming unit 60 is necessary. For example, a correction processing execution necessity confirmation screen P2 is pop-up displayed on the basic setting screen P1 shown in FIG.

  On the correction processing execution necessity confirmation screen P2, “YES / NO” is selected as to whether or not the correction processing can really be stopped. At this time, when the user wants to stop the correction process, the user presses the “YES” key K6. On the contrary, when it is desired to continue the correction process, the “NO” key K7 is pressed. Then, the process proceeds to step E9, and the control means 15 controls the operation means 16 so as to set a next correction execution time different from the preset correction execution interval. Thereafter, the process returns to step E1 to repeat the above-described processing.

  As described above, according to the color copying machine and the image forming method as the embodiment of the present invention, when the image is formed based on the arbitrary image information, the control unit 15 is set by the frequency setting unit 16A. Whether or not the correction time has been reached is determined based on the execution frequency, and the image forming unit 60 is corrected at the correction time based on the determination result.

  Therefore, the image forming unit 60 can be corrected at a correction execution interval at an arbitrarily set execution frequency. Thus, when the correction execution interval is set to be short according to the user's image quality requirement level, high image quality can always be maintained, and when the correction execution interval is set to be long, the correction process is performed. As a result, the time during which the apparatus cannot be used can be shortened as much as possible.

  Moreover, even if the process has already shifted to the correction process as shown in FIG. 6B, the correction process can be forcibly stopped by selecting the correction reservation button B8. can do.

  In this embodiment, with respect to the image forming units 10Y, 10M, 10C, and 10K, the image forming units 10Y and 10K that form toner images of Y, M, C, and BK colors on the photosensitive drums 1Y, 1M, 1C, and 1K. The case of having 10M, 10C, and 10K and the image transfer belt 6 for transferring the toner images formed on the photosensitive drums 1Y, 1M, 1C, and 1K for these colors has been described. The present invention can also be applied to a color image forming apparatus that forms a color image by superimposing colors on one transfer material conveying belt.

  The present invention is extremely suitable when applied to a tandem type color printer or copier having a intermediate transfer belt or a transfer material conveying belt and executing a process correction mode, a multi-function machine thereof, or the like.

1 is a conceptual diagram illustrating a configuration example of a color copying machine 100 as an embodiment of the present invention. 2 is a block diagram illustrating a configuration example of a control system of the color copying machine 100. FIG. A and B are conceptual diagrams illustrating a configuration example of the operation panel 48 and a display example of the correction execution timing setting screen P0. It is an image figure which shows the example of a display of the basic setting screen P1 in the display means. It is an image figure which shows the example of a display of the correction process execution necessity confirmation screen P2. A and B are time charts showing examples of correction execution in the color copying machine 100. 3 is a flowchart illustrating an example of image forming processing and correction condition setting processing in the color copying machine 100. 5 is a flowchart illustrating an example of correction execution determination processing in a control unit 15;

Explanation of symbols

1Y, 1M, 1C, 1K Photosensitive drum (image forming body)
3Y, 3M, 3C, 3K Image writing unit (image forming means)
4Y, 4M, 4C, 4K developing device (image forming means)
6 Intermediate transfer member (image forming member)
10Y, 10M, 10C, 10K Image forming unit (image forming means)
DESCRIPTION OF SYMBOLS 11 Temperature sensor 12 Color shift detection sensor 13 Density detection sensor 14 Non-volatile memory (memory | storage means)
DESCRIPTION OF SYMBOLS 15 Control means 16 Operation means 17 Fixing apparatus 18 Display means 48 Operation panel 60 Image forming means 100 Color copier 101 Copier main body 102 Image reading apparatus 201 Automatic document feeder 202 Document image scanning exposure apparatus

Claims (7)

An apparatus for forming an image based on arbitrary image information,
Image forming means;
A frequency setting operation means operated to arbitrarily set the execution frequency of correction processing in the image forming means;
Control means for determining whether or not the correction time has been reached based on the execution frequency set by the frequency setting operation means, and for correcting the image forming means at the correction time based on the determination result; An image forming apparatus comprising: A condition setting operation unit operated to set a correction execution condition in the image forming unit;
The control means includes
The image forming apparatus according to claim 1, wherein the image forming unit is corrected at the correction time based on the correction execution condition set by the condition setting operation unit.   The image forming apparatus according to claim 1, further comprising a stop instruction operation unit operated to instruct to stop correction processing in the image forming unit.   The image forming apparatus according to claim 1, further comprising a confirmation operation unit that is operated to confirm whether or not the execution of correction processing in the image forming unit is necessary.   The image forming apparatus according to claim 1, further comprising an execution instruction operation unit that is operated so as to instruct the execution of correction processing in the image forming unit. Storage means for storing the date and time when the image forming means was corrected last time;
The image forming apparatus according to claim 1, further comprising: a display unit that displays a previous correction date and time read from the storage unit or an elapsed time from the previous correction time to the present time. A method of forming an image based on arbitrary image information in an image forming system,
Set the execution frequency of the correction process in the image forming system and the correction execution condition in the correction process,
It is determined whether or not the correction time has been reached based on the preset execution frequency,
An image forming method, wherein the image forming system is corrected based on the correction execution condition at the determined correction time.

Images