JP4962463B2 - Image forming apparatus and image forming program - Google Patents

Description

  The present invention relates to an image forming apparatus and an image forming program.

  An image that is not transferred to the paper may be formed between the images transferred to the paper. Patent Document 1 discloses an image density calculation means for calculating an image density of a toner image in a transfer material facing area facing a transfer material conveyed to a transfer area in an image formable area on an image carrier, and the image The blank area width in the direction perpendicular to the transfer material moving direction with respect to the inter-image area between the transfer material facing area and the next transfer material facing area on the image carrier based on the image density calculation result by the density calculating means Determining means for determining whether or not it is necessary to create a cleaning blade protecting toner band, and a toner band image forming control means for controlling an image forming process of the toner band based on a determination result by the determining means. An image forming apparatus characterized by the above has been proposed.

  In some cases, a control patch is formed in the image transferred to the paper. Patent Document 2 discloses a patch forming unit that forms at least one patch row composed of a plurality of patches on a recording material of a predetermined length, and the density of the patch row on the recording material formed by the patch forming unit. Alternatively, detecting means for detecting chromaticity, conveying means for conveying the recording material at the time of detection by the detecting means, conveying speed of the recording material by the conveying means, and patch formation according to the predetermined length Control means for controlling the patch forming means and the conveying means by determining at least one of the number of patches formed by the means and the length of each patch, and based on the density or chromaticity detected by the detecting means Thus, there has been proposed an image forming apparatus having correction means for correcting image forming characteristics in the image forming means.

In Patent Document 3, as a technique for forming a toner band on a photosensitive drum, an electrostatic latent image for cleaning is dispersed in an inter-image area between the previous image forming area and the next image forming area on the photosensitive member. A special device is used to remove foreign matter such as paper dust that adheres to the surface of the photoreceptor by controlling the cleaning to be performed by a cleaning means without transferring a developed image obtained by developing the electrostatic latent image. There has been proposed an image forming apparatus that can be sufficiently removed without any problem.
Japanese Patent Publication No. 3835503 JP 2006-30564 A JP-A-4-317076

  An object of the present invention is to provide an image forming apparatus and an image forming program that effectively utilize non-image areas.

To achieve the above object, an image forming apparatus of the invention of claim 1 includes a first image carrier that rotates, a first electrostatic latent serving as an image to be printed on paper in the first image carrier on An electrostatic latent image forming unit that forms an image and forms a second electrostatic latent image that is an image for controlling image formation on the first image holding member, and the first electrostatic latent image And a developing means for developing the second electrostatic latent image with a color material, a first transfer means for transferring the color material image developed by the developing means to a second image holding member, and the first image holding. A first length, which is a length obtained by subtracting a length in the circumferential direction of the first image holding body in a region in which the first electrostatic latent image is written, from the circumference of the body is the second electrostatic latent image If longer than the second length is the circumferential length of the region to write, the second length to and a changing means for changing long below the first length Constructed.

Further, the invention of claim 2, in the invention of claim 1, wherein the second electrostatic latent image is formed on the image der so that for the purpose of discharge of the deterioration colorant from the developing unit.

The invention of claim 3 is the invention of claim 1 or 2, wherein the second electrostatic latent image is formed on so that is formed at the same position of the first image carrier.

According to a fourth aspect of the present invention, in the third aspect of the present invention, a blank area where no electrostatic latent image is formed is formed before and after the second electrostatic latent image in the circumferential direction of the first image carrier. The length in the circumferential direction of the first image carrier is the total length of the total area including the area where the first electrostatic latent image can be written, the area where the second electrostatic latent image can be written, and the blank area . Ri natural number multiple der the circumference of the image carrier, wherein the changing means, the second length, the first electrostatic latent image from the circumferential natural number times the length of the first image carrier the area to write the if circumferential direction shorter than the third length of minus the length, and the length of the 2 so that change longer below the length of the third.

According to a fifth aspect of the present invention, in the invention according to any one of the first to third aspects, a blank area in which no electrostatic latent image is formed before and after the second electrostatic latent image in the circumferential direction of the first image carrier. There is formed, the region in which the combination of the blank region first electrostatic latent image and the second electrostatic latent image as a person group, nature plurality of said sets of circumference of said first image carrier is formed to be several times, said changing means as the set of said plurality of the natural number multiple of the circumferential of the first image holding member, configured to modify longer second length Is done.

According to a sixth aspect of the present invention, in the fifth aspect of the present invention, there are a plurality of the developing means for each color material, and the second electrostatic latent image is used for testing the reproducibility of the color material image density. The first image, the second image for testing the reproducibility of the positional relationship between the plurality of color material images, and the second image for specifying the position of the color material image corresponding to the first electrostatic latent image. 3 and any one of a fourth image for controlling the discharge amount of the color material from the developing means, and the first image and the second image are the first image carrier. is formed in the same position, the type of an image formed on said set of the second electrostatic latent image of said plurality of configured so that different among the sets of the plurality of.

According to a seventh aspect of the invention, in the invention according to any one of the fourth to sixth aspects, the second electrostatic latent image and the blank area are formed prior to the formation of the first electrostatic latent image. Configured to be

The invention according to claim 8 is the invention according to claim 5 or 6 , wherein the first image , the second image, and the fourth image are arranged in a circumferential direction of the first image carrier. It is comprised so that it may form in parallel toward .

According to a ninth aspect of the present invention, there is provided an image forming program for forming a first electrostatic latent image as an image to be printed on a sheet on a rotating first image holding body and holding the first image. Electrostatic latent image forming means for forming a second electrostatic latent image which is an image for controlling image formation on the body, the first electrostatic latent image and the second electrostatic latent image as color materials Developing means for developing the first electrostatic latent image from the circumference of the first image holding body, first transfer means for transferring the color material image developed by the developing means to the second image holding body, A first length obtained by subtracting a length in the circumferential direction of the first image carrier in the writing area is a second length in the circumferential direction of the area in which the second electrostatic latent image is written . When the length is longer than the first length, the second length is changed to be longer than the first length .

  According to the first aspect of the present invention, the non-image area can be effectively used as compared with the case where the size of the second electrostatic latent image is not changed according to the image area.

According to the third aspect of the invention, as compared with the case where not constitute the present invention, it is Rukoto suppress the influence of the unevenness of the first image carrier.

According to the fourth aspect of the present invention, the non-image area can be effectively used as compared with the case where the present invention is not configured.
According to the invention of claim 5 , the non- image area can be effectively used as compared with the case where the present invention is not configured.

According to the invention of claim 6, as compared with the case where not constitute the present invention, it is resulting in higher accuracy such as density control or position control.

According to the invention of claim 7, the size of the region of the second electrostatic latent image can be increased as compared with the case where the present invention is not configured.

According to the eighth aspect of the present invention, the area of the second electrostatic latent image can be used more efficiently than in the case where the present invention is not configured.

  According to the ninth aspect of the present invention, it is possible to effectively use the non-image area as compared with the case where the size of the second electrostatic latent image is not changed according to the image area.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

  First, the configuration of the image forming apparatus 100 will be described with reference to FIG.

  FIG. 1 is a diagram showing an outline of the configuration of the image forming apparatus 100.

  As shown in FIG. 1, an image forming apparatus 100 includes a paper feeding device 1, a paper feed unit 2, a secondary transfer roll 3, an intermediate transfer belt 4 used as a second image carrier in the present embodiment, a fixing device 5, A transfer belt cleaning device 6, an intermediate transfer belt reference position detecting means 7, a photosensitive drum 8 used as a first image carrier in this embodiment, an exposure device 9 used as an electrostatic latent image forming means in this embodiment, The charging device 10, the photosensitive drum cleaning device 11, the primary transfer roll 12 used as the first transfer means in this embodiment, the ATC (Auto Toner Control) sensor 13, and the developing device used as the developing means in this embodiment. 14, ADC (Auto Density Control) sensor 15, display / operation unit 16, control unit 17 also used as changing means in this embodiment, register sensor 1 Equipped with a.

  The paper feeding device 1 stores paper used for image formation in the image forming device 1.

  The paper feed unit 2 sends out the paper stored in the paper feeding device 1 to the conveyance path.

  The secondary transfer roll 3 is disposed in pressure contact with the toner image holding surface side of the intermediate transfer belt 4, and a toner image held on the intermediate transfer belt is applied by applying a bias voltage higher than that on the intermediate transfer belt 4. Secondary transfer is performed on a sheet in contact with the secondary transfer roll 3. The primary transfer is performed on the intermediate transfer belt 4 from a photoconductor described later.

  The intermediate transfer belt 4 is supported by several tension rolls so as to be rotatable in the direction of arrow a.

  The fixing device 5 fixes the toner on the sheet on which the toner image is transferred by the secondary transfer roll 3.

  The transfer belt cleaning device 6 collects the toner on the intermediate transfer belt 4 that has not been transferred by the secondary transfer roll 3.

  The intermediate transfer belt reference position detection unit 7 detects a mark provided on the intermediate transfer belt 4 as a reference position.

  The photosensitive drum 8 is a drum as an image carrier used in an electrophotographic system, and the electrostatic latent image formed by the exposure device 9 is developed by the developing device 14 to form a toner image.

  The exposure device 9 irradiates the photosensitive drum 8 with light to form an electrostatic latent image on the photosensitive drum 8.

  The charging device 10 uniformly charges the surface of the photosensitive drum 8 so that an electrostatic latent image is formed by the exposure device 9.

  The photosensitive drum cleaning device 11 cleans the photosensitive drum 8 after the primary transfer on the photosensitive drum 8.

  In the photosensitive drum cleaning device 11, the toner remaining after the primary transfer on the photosensitive drum 8 is scraped off by the blade of the photosensitive drum cleaning device 11 to remove the toner, as well as talc, ozone, and the like. Foreign matter on the surface of the photosensitive drum is removed.

  The primary transfer roll 12 is disposed in pressure contact with the non-toner image arrangement surface side of the intermediate transfer belt 4 and is applied with a bias voltage higher than the surface of the photosensitive drum 8 on which the toner image is disposed, The toner image on the photosensitive drum 8 is transferred to the intermediate transfer belt 4 that passes between the photosensitive drum 8 and the primary transfer roll 12.

  The ATC sensor 13 is a sensor that detects the toner density in the developing device 14. For example, a magnetic permeability sensor can be used as the ATC sensor 13.

  The developing device 14 has a developer composed of a non-magnetic toner and a magnetic carrier inside, charges the stirred and mixed developer to a predetermined polarity, and uses the developer to develop an electrostatic latent image on the photosensitive drum 8. Develop the image.

  The exposure device 9, the charging device 10, the photosensitive device cleaning device 11, the primary transfer roll 12, and the ATC sensor 13 disposed around the photosensitive drum 8 and the photosensitive drum 8 are respectively for Y (yellow), Four devices are provided for M (magenta), C (cyan), and K (black). As shown in FIG. 1, a device for Y (yellow), a device for M (magenta), and a C (cyan) ) Device and K (black) device are arranged in parallel on the intermediate transfer drum 4.

  In this embodiment, the ADC sensor 15 that reads the procompact used as the first image is a sensor that measures the density of the procompact on the intermediate transfer belt 4. The ADC sensor 15 is configured by, for example, a reflective photosensor. Note that performing density control of an image image in accordance with the density measured by the ADC sensor 15 is referred to as process control (hereinafter referred to as process control).

  The display / operation unit 16 includes a liquid crystal touch panel and is a user interface screen.

  The control unit 17 includes a CPU and a memory, and performs overall control of the image forming apparatus 100 and also controls control related to formation of a toner image transferred to the intermediate transfer belt 4.

  The regicon sensor 18 detects the positional relationship between the color images in the patch area. The control of the positional relationship of each color image of the image image according to the position measured by the registration sensor is called registration control (hereinafter referred to as registration control), and the toner image read by the registration sensor is referred to as a registration control patch. Call. In this example, a regicon patch was used as the second image.

  A patch written on the intermediate transfer belt 4 for reference of the position of an image image on which a toner image to be formed on a sheet is arranged is called an image lead patch. The timing for sending the sheet to the transfer point is taken with the image lead patch as a reference. In this embodiment, an image lead patch is used as the third image.

  The developing device 14 forms an image different from the image toner image, which is the first electrostatic latent image in this embodiment used for image formation on the paper, in the patch area on the photosensitive drum 8.

  The image formed in the patch area is referred to as a patch image which is the second electrostatic latent image in the present embodiment. In the patch area, the blade protection of the photosensitive drum cleaning device 11 and the developing device 14 include The toner band formed for discharging the deteriorated toner, the image lead patch for reference of the position of the image image where the toner image to be formed on the paper is arranged, and the toner image on the intermediate transfer belt 4 Procompacts formed for density detection and registration compacs formed for color registration are formed. In this embodiment, the toner band is used as the fourth image.

  Next, the function of the control unit 17 will be described with reference to FIG.

  FIG. 2 is a block diagram illustrating functions of the control unit 17.

  The control unit 17 includes an image density detection signal processing unit 21, a patch forming unit 22, a print controller 23, an image writing timing control unit 24, an image count unit 25, a density correction control unit 26, an image count area calculation unit 28, and a toner density. A detection signal processing / toner supply amount control unit 29, an image processing unit 30, and a pulse width modulation circuit 31 are included.

  The image density detection signal processing unit 21 performs processing based on signals detected by the ADC sensor 15 and the regicon sensor 18.

  For example, the image density detection signal processing unit 21 sends a signal to the paper feed unit 2 based on the position of the image lead patch on the intermediate drum detected by the regicon sensor 18, and the timing at which the paper is sent out from the paper feed unit 2 Be controlled.

  The image density detection signal processing unit 21 transmits a signal related to image toner image formation based on the signals detected by the ADC sensor 15 and the regicon sensor 18, and sends a signal related to patch formation to the patch forming unit 22. Processing and processing for sending a signal related to density correction to the density correction control unit 26 are performed.

  Upon receiving an instruction from the print controller 23, the patch forming unit 22 performs photosensitivity based on the information sent from the image density detection signal processing unit 21 and the intermediate transfer belt reference position detection unit 7 and the image image sent from the print controller 23. The patch image data formed on the body drum 8 is formed.

  The print controller 23 transmits a print start signal based on an instruction from the display / operation unit 16 or a print job instruction received by the image forming apparatus 100.

  In addition, image data of an image that is an image to be printed on paper is sent to the patch forming unit 22 and the image counting unit 25.

  The image writing timing control unit 24 writes the electrostatic latent image on the respective photosensitive drums 8 for Y (yellow), M (magenta), C (cyan), and K (black) by the exposure device 9. The timing control is performed.

  The image count unit 25 counts the amount of image data of the image data processed by the image processing unit 30.

  The density correction control unit 26 includes an image density target value storage unit 27, and based on the image density value sent from the image density detection signal processing unit 21 and the target value stored in the image density target value storage unit 27. Gradation correction data is calculated and sent to the image processing unit 30, and toner replenishment amount data is sent to the toner density detection signal processing unit / toner supply amount control unit 29.

  The image count area calculation unit 28 counts the image data amount for each area.

  The toner density detection signal processing unit / toner supply amount control unit 29 is predicted from the detection value by the ATC sensor 13, the density correction value sent from the density correction control unit 26, and the image data amount sent from the image count area calculation unit 28. The toner replenishment amount is obtained based on the toner consumption amount.

  The image processing unit 30 generates image data of an electrostatic latent image formed on the photosensitive drum 8. The exposure device 9 forms an electrostatic latent image on the photosensitive drum 8 based on the image generated by the image processing unit 30.

  The image generated by the image processing unit 30 includes a patch image and an image image formed on the photosensitive drum 8 (an image image here is an image printed on paper). .

  The pulse width modulation circuit 31 converts the digital image data generated by the image processing unit 30 into a pulse ON time length.

  Next, the toner image transferred to the intermediate transfer belt 4 of the image forming apparatus 100 will be described with reference to FIG.

  FIG. 3 is a schematic diagram showing a toner image transferred to the intermediate transfer belt 4.

  3A is a schematic diagram showing a toner image transferred from the photosensitive drum to the intermediate transfer belt in the image forming apparatus according to the conventional technique, and FIG. 3B is an intermediate transfer of the image forming apparatus 100. FIG. 6 is a schematic diagram illustrating a toner image transferred to a belt. As shown in FIG. 3A, in the conventional image forming apparatus, the patch image formation cycle is set to be the same as the cycle of the photosensitive drum so as not to be affected by unevenness of the surface state of the photosensitive drum or uneven rotation. When the area of the image image transferred to the paper is small, a vacant area (reference number 301) in which neither the patch image nor the image image is formed occurs. Then, patches that could not be written in the patch area were written with a patch inter-image secured. In some cases, a patch cycle is provided after the image is finished, not in the inter-image.

  Here, in the image forming apparatus 100, the area of the patch image is widened (reference number 302) in order to effectively use the above-described vacant area.

  Next, a process of forming a patch image in the image forming apparatus 100 will be described with reference to the flowchart of FIG.

  As shown in FIG. 4, first, when a print start signal is issued from the print controller 23 (step 401), the image data that is image data to be printed on the paper and the screen setting conditions are displayed from the print controller 23. It is sent to the image processing unit 30 through the counting unit 25 (step 402).

  When a print start signal is issued from the print controller 23 (step 401), patch image data and screen settings are sent from the patch forming unit 22 to the image processing unit 30 via the image count unit 25 (step 403). .

  The image image data sent from the print controller 23 and the patch image data sent from the patch forming unit 22 are counted by the image counting unit 25 and sent to the image processing unit 30 (step 404). ).

  Then, under the control of the image writing timing control unit 24, the image data sent to the image processing unit is exposed to the photosensitive drum 8 by the exposure device 9 (step 405).

  At that time, the photosensitive drum 8 is exposed to a patch image and an image image.

  The electrostatic latent image of the patch image and the image image exposed on the photosensitive drum 8 is developed into a toner image by the developing device 4 (step 406).

  The toner images developed on the photosensitive drums 8 are transferred from the respective photosensitive drums 8 to the intermediate transfer belt 4 by the primary transfer roll 12 (step 407).

  At that time, a part of toner forming a toner band in the patch image developed on the photosensitive drum 8 remains on the photosensitive drum 8 without being transferred to the intermediate transfer belt 4 by the primary transfer roll 12, As the drum 8 rotates, it is supplied to the blade of the photosensitive drum cleaning device 11 and scraped off.

  Further, the toner image that is primarily transferred from the patch image developed on the photosensitive drum 8 is collected by the transfer belt cleaning device 6.

  Next, the contents of the patch image formed on the photosensitive drum 8 will be described with reference to FIG.

  FIG. 5 is a schematic diagram showing the patch image, and FIG. 5A is a schematic diagram showing a case where the patch image and the image image are developed by one rotation of the photosensitive drum 8, and FIG. ) Is a schematic diagram showing a case where a patch image and an image image are developed by two rotations of the photosensitive drum 8.

  As shown in FIG. 3B, the patch image and the image image shown in FIG. 5A are obtained by forming a wider area of the patch image than the case where the configuration of the present invention is not provided. .

  The patch image and the image image shown in FIG. 5A are toner images developed on the photosensitive drum 8 of the image forming apparatus 100.

  As shown in FIG. 5A, when a patch image and an image image are formed in one drum cycle, the toner image of the patch image is first developed as the photosensitive drum 8 rotates (see Next, the toner image of the image image is developed (reference number 502).

  However, the intermediate transfer belt 4 prevents the patch image on the intermediate transfer belt 4 from being transferred onto the sheet by the secondary transfer roll 3 after a part of the toner image of the patch image is transferred from the photosensitive drum 8 to the intermediate transfer belt 4. Before and after the toner image of the upper patch image passes through the secondary transfer roll 3, application of a bias voltage for transferring the toner image to the paper is turned off / on.

  That is, before the toner image of the patch image passes, the bias voltage for transferring the toner image on the intermediate transfer belt 4 to the sheet is turned off.

  Then, the toner image of the patch image on the intermediate transfer belt 4 passes through the secondary transfer roll 3 without being transferred to the paper.

  Thereafter, after the toner image of the patch image on the intermediate transfer belt 4 passes through the secondary transfer roll 3, the bias voltage for transferring the toner image on the intermediate transfer belt 4 to the sheet is turned on, and then the secondary transfer is performed. The toner image of the image on the intermediate transfer belt 4 that passes through the roll 3 is transferred to a sheet.

  Thus, since the bias voltage is turned off / on before and after the toner image of the patch image on the intermediate transfer belt 4 passes through the secondary transfer roll 3, the secondary transfer roll is switched during the switching time of the bias voltage. The toner image of the patch image is not formed in the region of the intermediate transfer belt 4 that passes 3 (reference numbers 503 and 504).

  A blank area on the intermediate transfer belt 4 that passes through the secondary transfer roll 3 during the switching time of the bias voltage before the toner image of the patch image on the intermediate transfer belt 4 passes through the secondary transfer roll 3 is shown in FIG. ) Is indicated by B1 (reference number 503), and the blank area on the intermediate transfer belt 4 that passes through the secondary transfer roll 3 during the switching time of the bias voltage after the toner image of the patch image has passed through the secondary transfer roll 3 is shown in FIG. In FIG. 5A, it is shown as B2 (reference number 504).

  When one patch image and one image image are developed, the end (reference number 506) of the developed image image comes to the end portion (reference number 505) of the drum cycle of the photosensitive drum 8. Adjust and develop. By adjusting in this way, it corresponds to the switching time of the area of the image image and the bias voltage of the secondary transfer roll 3 from the circumferential shape of one rotation of the photosensitive drum 8 on which one patch image and the image image are developed. The area excluding the blank areas B1 and B2 to be processed can be set as an area where the patch image is developed, and a patch image area as wide as possible is secured.

  In FIG. 5 (a), one patch image and one image image are developed for one rotation of the drum. In FIG. 5 (a), this one patch image, the blank portion before and after that, and one image image. This set is called one panel. Further, in FIG. 5B, one patch image and one image image are developed for two revolutions of the drum, and one patch image of FIG. 5B, a blank portion before and after that, and an image of one image. This set is called one panel. In FIG. 6, two patch images and two image images are developed for three revolutions of the drum. In FIG. 6, a set of the two patch images and two images of blank portions before and after the two patch images is called one panel. . Thus, here, one panel is defined as a set of patch images and image images synchronized with the drum cycle.

  That is, when one patch image and one image image are developed, from the panel start portion (reference number 508) of the photosensitive drum 8 to the panel end portion (reference number 505) measured by the drum cycle. The length in the circumferential direction is B1 + the length in the circumferential direction of the patch image + B2 + the length in the circumferential direction of the image image (reference number 507).

  Next, the image forming apparatus 100 is configured to transfer one patch image and an image image to the intermediate transfer belt 4 by two rotations of the photosensitive drum 8, as shown in FIG. 5B. The Also in this case, the end of one image (reference number 509) is positioned at the end (reference number 510) of the peripheral surface of the two drums. An area obtained by excluding the area of the image image and the blank areas B1 and B2 corresponding to the switching time of the bias voltage of the secondary transfer roll 3 from the area of the two circumferential surfaces of the photosensitive drum 8 is the patch image. Set as an area.

  Next, an example in which regions of a plurality of patch images and a plurality of image images are set in a region corresponding to a plurality of rotations of the photosensitive drum 8 will be described with reference to FIG. Here, in order to eliminate the influence of the unevenness of the photosensitive drum, it is desirable to always form them at the same position. However, since the interimage becomes too long, the influence of the unevenness of the photosensitive drum is suppressed. However, in order to shorten the inter-image and ensure productivity, images and patches are arranged as shown in FIG.

  FIG. 6 is a schematic diagram showing the intermediate transfer belt 4 to which two patch images and two image images are transferred by rotating the photosensitive drum 8 three times.

  As shown in FIG. 6, the image forming apparatus 100 is also configured to develop a plurality of patch images and a plurality of image images by a plurality of rotations of the photosensitive drum 8. Also at this time, the end (reference number 601) of the last developed image among the plurality of image images is developed at the end of the last rotation of the photosensitive drum 8 of the plurality of rotations. Adjusted.

  Then, the first patch image (reference number 603) developed among the plurality of patch images in FIG. 6 is synchronized with the first patch image of the next panel after the plurality of rotations of the photosensitive drum 8, The patch image (reference number 604) developed for the second time among the plurality of patch images is not synchronized with the patch image for 603 developed for the first time in the drum cycle of the photosensitive drum 8.

  Considering the first patch image as a reference, the patch image is synchronized with the drum cycle of the photosensitive drum 8 (reference number 603), and the patch image is not synchronized with the drum cycle of the photosensitive drum (reference number 604). The first patch image and the second patch image may have different image contents. That is, the patch image (reference number 603) synchronized with the drum cycle includes a toner band (reference number 701), an image lead patch (reference number 702), and a procompatch (reference number 703) as shown in FIG. ), A regicon patch (reference number 704) is developed, and a patch image (reference number 604) that does not synchronize with the drum cycle includes a toner band (reference number 705), an image lead patch (reference number 704), as shown in FIG. Only reference number 706) may be developed.

  As described above, in the image forming apparatus 100, the types of patches developed into the patch image can be made different.

  Further, as shown in FIG. 7 (a), the registration compasses and procompatches developed as patch images are developed with a predetermined length, but the image lead has a property that the position of the image image is grasped. The length is variable according to the size of the image.

  Further, the toner band is also variable in length according to the size of the image as in the image lead as shown in FIG.

  Next, processing for patch formation performed by the patch forming unit 22 will be described with reference to FIG.

  FIG. 8 is a flowchart showing processing for patch formation performed by the patch forming unit 22.

  If the patch forming unit 22 determines that the registration control patch creation timing is reached (YES in step 801), a registration control patch is created at a designated position in the patch image area (step 802).

  If the patch forming unit 22 determines that the generation timing of the procompatch (YES in step 803), a procompatch is generated at a designated position in the patch image area (step 804).

  If the patch forming unit 22 determines that the toner band creation timing is reached (YES in step 805), a toner band is created at a designated position in the patch image area (step 806).

  Then, if a regicon patch, a procompatch, or a toner band is created or not created in the patch image area, an image lead patch is created at a designated position in the patch image area (step 807).

  Since the image lead patch is provided to clarify the reference of the position of the image image, it may be preferentially present over other patches as being created in pairs with the image each time.

  As described above, the priority order that exists in the patch image may be provided in the patch image among the regi-con patch, the pro-compatch, the toner band, and the image lead.

  In addition, when one circumference is different between the photoconductors, for example, only the diameter of the photoconductor corresponding to the black image is larger than that of the other color photoconductors, the patch region correspondingly corresponds to the difference. The image may be changed. In other words, for example, as shown in FIG. 6, when YMC can be one panel with three drums, if only K is 1.5 times the circumference, YMC 603 and 604 are not synchronized, but K is also synchronized with 603 and 604. When a patch to be received comes, the timing for writing a patch other than the register control patch in the image written in the patch area may be different between YMC and K.

  The present invention can be used in an image forming apparatus and an image forming program.

1 is a schematic diagram illustrating a configuration of an image forming apparatus 100. FIG. The block diagram which shows the function of the control part 17. FIG. FIG. 4 is a schematic diagram illustrating a toner image transferred to the intermediate transfer belt. 3 is a flowchart showing processing performed in the image forming apparatus 100. FIG. 6 is a diagram showing a positional relationship between a patch image formed on the photosensitive drum 8 and an image image. FIG. 4 is a schematic diagram showing that a plurality of patch images and image images are transferred to the intermediate transfer belt 4 by a plurality of rotations of the photosensitive drum 8. FIG. 3 is a schematic diagram showing a drum cycle of a photosensitive drum, a patch image that is synchronized, and a batch image that is not synchronized. 5 is a flowchart showing processing performed in the patch forming unit 22. FIG. 6 is a schematic diagram showing a toner image transferred to an intermediate transfer belt by a conventional technique.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Paper feeder 2 Paper feed part 3 Secondary transfer roll 4 Intermediate transfer belt 5 Fixing device 6 Transfer belt cleaning device 7 Intermediate transfer belt reference position detection means 8 Photoconductor 9 Exposure device 10 Charging device 11 Photoconductor drum cleaning device DESCRIPTION OF SYMBOLS 12 Primary transfer roll 13 ATC sensor 14 Developing apparatus 15 ADC sensor 16 Display / operation part 17 Control part 18 Resistor sensor 21 Image density detection signal processing part 22 Patch formation part 23 Print controller 24 Image writing timing control part 25 Image count part 26 Density correction control unit 27 Image density target value storage unit 28 Calculation unit for each image count area 29 Toner density detection signal processing unit / toner supply amount control unit 30 Image processing unit 31 Pulse width modulation circuit

Claims (9)

A first image carrier that rotates,
A first electrostatic latent image that is an image to be printed on a sheet is formed on the first image carrier , and a second static image is an image for controlling image formation on the first image carrier. An electrostatic latent image forming means for forming an electrostatic latent image;
Developing means for developing the first electrostatic latent image and the second electrostatic latent image with a color material;
A first transfer means for transferring the color material image developed by the developing means to a second image carrier;
A first length, which is a length obtained by subtracting the length in the circumferential direction of the first image carrier from the circumferential length of the first image carrier, is the second length . And changing means for changing the second length to be less than or equal to the first length when the electrostatic latent image writing area is longer than a second length that is the length in the circumferential direction. Image forming apparatus. It said second electrostatic latent image,
The image forming apparatus of an image Der Ru claim 1, wherein for the purpose of discharge of the deterioration colorant from the developing unit. It said second electrostatic latent image forming apparatus according to claim 1 or 2, wherein is formed at the same position of the first image carrier. A blank area where no electrostatic latent image is formed is formed before and after the second electrostatic latent image in the circumferential direction of the first image carrier , and the area where the first electrostatic latent image can be written and the second static image. the length of the first image carrier circumferential direction of the total area and area to write the electrostatic latent image by combining the said blank region Ri natural number multiple der of circumference of said first image holding member,
The changing means is
The second length is a third length obtained by subtracting a length in the circumferential direction of an area where the first electrostatic latent image can be written from a length that is a natural number times the circumference of the first image carrier. The image forming apparatus according to claim 3 , wherein when the length is short, the length of the second is changed to be longer than the third length . Blank areas where no electrostatic latent image is formed are formed before and after the second electrostatic latent image in the circumferential direction of the first image carrier, and the first electrostatic latent image and the second electrostatic latent image are formed. wherein an area obtained by combining the blank area as human pair, is formed such that a plurality of the set is a natural number multiple of the circumferential of the first image carrier and,
The changing means is
As the plurality of the set is a natural number multiple of the circumferential of the first image carrier, the image forming apparatus according to any one to claims 1 to 3 to change the second length longer. There are a plurality of developing means for each color material,
The second electrostatic latent image includes a first image for testing the reproducibility of the density of the color material image, a second image for testing the reproducibility of the positional relationship between the plurality of color material images, Either a third image for specifying the position of the color material image corresponding to the first electrostatic latent image, or a fourth image for controlling the discharge amount of the color material from the developing means Including statues,
The first image and the second image are formed at the same position of the first image carrier;
The types of images formed on the second electrostatic latent images of the plurality of sets are different among the plurality of sets.
The image forming apparatus according to claim 5. The image forming apparatus according to claim 4 , wherein the second electrostatic latent image and the blank area are formed prior to the formation of the first electrostatic latent image . The image forming apparatus according to claim 5 , wherein the first image, the second image, and the fourth image are formed in parallel toward a circumferential direction of the first image carrier . Computer
A first electrostatic latent image, which is an image to be printed on paper, is formed on the rotating first image carrier , and a second image is an image for controlling image formation on the first image carrier. An electrostatic latent image forming means for forming an electrostatic latent image;
Developing means for developing the first electrostatic latent image and the second electrostatic latent image with a color material;
A first transfer means for transferring the color material image developed by the developing means to a second image carrier;
A first length, which is a length obtained by subtracting the length in the circumferential direction of the first image carrier from the circumferential length of the first image carrier, is the second length . In order to function as a changing means for changing the second length to be less than or equal to the first length when the area in which the electrostatic latent image is written is longer than the second length which is the length in the circumferential direction. image formation program.

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