JP2013225012A - Image formation control device, image forming apparatus, and control method of image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce a time required for removing a toner forming a pattern for positional deviation correction in an image forming apparatus.SOLUTION: An image formation control device controls image formation output for forming an image on a sheet conveyed by a roller, extends a detection period of a paper feed error to determine whether or not feeding of a sheet is completed when feeding of a sheet is expected to be delayed due to deterioration of a paper feeding roller, and transmits image information of the first page before delaying a timing to start transmission of image information of the subsequent page according to the length of the extended detection period.

Description

  The present invention relates to an image forming control apparatus, an image forming apparatus, and an image forming apparatus control method, and more particularly to mechanism control according to deterioration of a paper transport mechanism.

  In recent years, there has been a tendency to digitize information, and image processing apparatuses such as printers and facsimiles used for outputting digitized information and scanners used for digitizing documents have become indispensable devices. Such an image processing apparatus is often configured as a multifunction machine that can be used as a printer, a facsimile, a scanner, or a copier by providing an imaging function, an image forming function, a communication function, and the like.

  Among such image processing apparatuses, electrophotographic image forming apparatuses are widely used in image forming apparatuses used for outputting digitized documents. In an electrophotographic image forming apparatus, an electrostatic latent image is formed by exposing a photoreceptor, and the electrostatic latent image is developed using a developer such as toner to form a toner image. Paper output is performed by transferring the toner image onto paper.

  In such an electrophotographic image forming apparatus, the toner image is transferred onto the paper by feeding the paper stacked on the paper feeding device one by one in accordance with the transfer timing of the developed toner image. The As a method of matching the toner image transfer timing with the paper feeding timing, the paper is temporarily stopped by the pair of registration rollers before the transfer position, and the pair of registration rollers is driven in accordance with the toner image transfer timing. A configuration for feeding to the transfer position is used.

  When the paper cannot be normally conveyed due to a paper jam or the like during the conveyance (jam error), printing is interrupted. However, if the conveyance roller is worn, the probability of occurrence of a jam error increases. As a technique for avoiding this, a technique for making the jam detection time variable is already known (see, for example, Patent Document 1).

  In Patent Document 1, when wear occurs in a paper feed roller for feeding out the paper loaded on the paper feed device, paper feed is started after shortening the period until the paper feed roller is driven after receiving image forming data. The timing is advanced and the period for detecting a paper feed error after the start of paper feed is lengthened. Thereby, even if the paper feed timing is delayed due to wear of the paper feed roller, control is performed so that it is not detected as an error.

  When the paper is fed out by the paper feed roller, there is a possibility that a “feeding” state occurs in which the next paper is fed out somewhat due to friction with the paper stacked on top. When this follow-up occurs, when the next sheet is transported, the transport is started from a slightly advanced state. As a result, the sheet may reach the registration roller at an earlier timing than expected.

  As described above, when the paper reaches the registration roller at a timing earlier than the assumed timing, the paper being conveyed may reach the rear end of the preceding paper. This is partly because the conveyance speed of the paper feed roller is generally faster than the conveyance speed of the registration rollers.

  When the paper being transported reaches the trailing edge of the preceding paper, the detection state of the sensor for detecting the end of transport of the preceding paper does not change, and the paper being transported The paper is continuously conveyed to the paper being jammed, and jamming occurs. Such a problem is more likely to occur by advancing the paper conveyance start timing as disclosed in Patent Document 1.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to suitably prevent occurrence of a paper feed error in a state where a roller for transporting paper is worn.

  In order to solve the above-described problem, an aspect of the present invention is an image formation control device that controls an image formation output that forms an image on a sheet conveyed by a roller, and that performs image formation output. An image information output unit that transmits image information of an image to be output to each unit for each page, and the sheet is supplied from a storage unit that stores the sheet in response to the start of transmission of the image information for each page. Based on an output signal of a paper feed roller drive control unit that starts rotation of a paper feed roller for paper and a paper detection sensor that detects the paper in the paper feed path and outputs a detection signal, the paper feed roller A paper feed success / failure judgment unit that judges whether or not the paper is completed within a predetermined detection period, and the paper feed success / failure judgment unit delays paper feed due to deterioration of the paper feed roller. Is predicted In this state, the detection period is extended to determine whether the paper feeding is completed, and the image information output unit may delay the paper feeding due to the deterioration of the paper feeding roller. In a predicted state, after transmitting image information of one page, the timing of starting transmission of image information of the next page is delayed according to a period in which the detection period is extended.

  Another aspect of the present invention is an image forming apparatus including the image forming control apparatus described above.

  According to still another aspect of the present invention, there is provided a control method for an image forming apparatus for controlling the transport of the paper in an image forming control apparatus for forming an image on a paper transported by a roller. Image information of an image to be output is transmitted page by page to the image forming unit to be executed, and the sheet is fed from the storage unit in which the sheet is stored in response to the start of transmission of the image information for each page. The paper feed roller starts rotating, detects the paper in the paper feed path, and outputs a detection signal. Based on the output signal of the paper detection sensor, the paper is fed within a detection period. In the state where it is predicted that the paper feeding will be delayed due to the deterioration of the paper feeding roller, the detection period is extended and the paper feeding is completed. Whether or not Determining, after transmitting the image information of one page, the timing of starting the transmission of the image information of the next Peji, and wherein the delaying in response to a period obtained by extending the sensing period.

  According to the present invention, it is possible to suitably prevent the occurrence of a paper feed error in a state where a roller for transporting paper is worn.

1 is a block diagram illustrating a hardware configuration of an image forming apparatus according to an embodiment of the present invention. 1 is a diagram illustrating a functional configuration of an image forming apparatus according to an embodiment of the present invention. 1 is a diagram illustrating a configuration of a print engine according to an embodiment of the present invention. It is a figure which shows the control structure of the print engine by the engine control part which concerns on embodiment of this invention. 6 is a timing chart showing general sheet conveyance timing. It is a timing chart which shows the timing of paper conveyance at the time of roller wear concerning a prior art. 6 is a timing chart showing the timing of sheet conveyance when the roller is worn according to an embodiment of the present invention. It is a figure which shows the judgment item of abrasion of the paper feed roller which concerns on embodiment of this invention. 6 is a timing chart showing the timing of sheet conveyance when the roller is worn according to an embodiment of the present invention. It is a flowchart which shows the abrasion judgment operation | movement of the paper feed roller which concerns on embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the present embodiment, an image forming apparatus as an MFP (Multi Function Peripheral) will be described as an example. The image forming apparatus according to the present embodiment is an electrophotographic image forming apparatus, and controls roller and jam (paper jam) detection according to wear of a transport roller for transporting a sheet as a medium that is an image formation output target. Is the gist.

  FIG. 1 is a block diagram illustrating a hardware configuration of an image forming apparatus 1 according to the present embodiment. As shown in FIG. 1, the image forming apparatus 1 according to the present embodiment includes an engine that executes image formation in addition to the same configuration as an information processing terminal such as a general server or a PC (Personal Computer). That is, the image forming apparatus 1 according to the present embodiment includes a CPU (Central Processing Unit) 10, a RAM (Random Access Memory) 11, a ROM (Read Only Memory) 12, an engine 13, an HDD (Hard Disk Drive) 14, and an I / O. F15 is connected via the bus 18. Further, an LCD (Liquid Crystal Display) 16 and an operation unit 17 are connected to the I / F 15.

  The CPU 10 is a calculation unit and controls the operation of the entire image forming apparatus 1. The RAM 11 is a volatile storage medium capable of reading and writing information at high speed, and is used as a work area when the CPU 10 processes information. The ROM 12 is a read-only nonvolatile storage medium, and stores programs such as firmware. The engine 13 is a mechanism that actually executes image formation output in the image forming apparatus 1.

  The HDD 14 is a nonvolatile storage medium capable of reading and writing information, and stores an OS (Operating System), various control programs, application programs, and the like. The I / F 15 connects and controls the bus 18 and various hardware and networks. The LCD 16 is a visual user interface for the user to check the state of the image forming apparatus 1. The operation unit 17 is a user interface such as a keyboard and a mouse for the user to input information to the image forming apparatus 1.

  In such a hardware configuration, a program stored in a recording medium such as the ROM 12, the HDD 14, or an optical disk (not shown) is read into the RAM 11, and the CPU 10 performs calculations according to those programs, thereby configuring a software control unit. The A functional block that realizes the functions of the image forming apparatus 1 according to the present embodiment is configured by a combination of the software control unit configured as described above and hardware.

  Next, the functional configuration of the image forming apparatus 1 according to the present embodiment will be described with reference to FIG. FIG. 2 is a block diagram illustrating a functional configuration of the image forming apparatus 1 according to the present embodiment. As shown in FIG. 2, the image forming apparatus 1 according to the present embodiment includes a controller 20, an ADF (Auto Document Feeder) 110, a scanner unit 22, a paper discharge tray 23, a display panel 24, and a paper feed table. 25, a print engine 26, a paper discharge tray 27, and a network I / F 28.

  The controller 20 includes a main control unit 30, an engine control unit 31, an input / output control unit 32, an image processing unit 33, and an operation display control unit 34. As shown in FIG. 2, the image forming apparatus 1 according to the present embodiment is configured as a multifunction machine having a scanner unit 22 and a print engine 26. In FIG. 2, the electrical connection is indicated by solid arrows, and the flow of paper is indicated by broken arrows.

  The display panel 24 is an output interface that visually displays the state of the image forming apparatus 1 and is an input when the user directly operates the image forming apparatus 1 or inputs information to the image forming apparatus 1 as a touch panel. It is also an interface (operation unit). The network I / F 28 is an interface for the image forming apparatus 1 to communicate with other devices via the network, and uses an Ethernet (registered trademark) or a USB (Universal Serial Bus) interface.

  The controller 20 is configured by a combination of software and hardware. Specifically, a control program such as firmware stored in a nonvolatile recording medium such as the ROM 12 and the nonvolatile memory and the HDD 14 and the optical disk is loaded into a volatile memory (hereinafter referred to as a memory) such as the RAM 11 to control the CPU 10. The controller 20 is configured by a software control unit configured according to the above and hardware such as an integrated circuit. The controller 20 functions as a control unit that controls the entire image forming apparatus 1.

  The main control unit 30 plays a role of controlling each unit included in the controller 20 and gives a command to each unit of the controller 20. The engine control unit 31 serves as a drive unit that controls or drives the print engine 26, the scanner unit 22, and the like. The input / output control unit 32 inputs a signal or a command input via the network I / F 28 to the main control unit 30. The main control unit 30 controls the input / output control unit 32 and accesses other devices via the network I / F 28.

  The image processing unit 33 generates drawing information based on the print information included in the input print job under the control of the main control unit 30. The drawing information is information for drawing an image to be formed in the image forming operation by the print engine 26 as an image forming unit. The print information included in the print job is image information converted into a format that can be recognized by the image forming apparatus 1 by a printer driver installed in an information processing apparatus such as a PC. The operation display control unit 34 displays information on the display panel 24 or notifies the main control unit 30 of information input via the display panel 24.

  When the image forming apparatus 1 operates as a printer, first, the input / output control unit 32 receives a print job via the network I / F 28. The input / output control unit 32 transfers the received print job to the main control unit 30. When receiving the print job, the main control unit 30 controls the image processing unit 33 to generate drawing information based on the print information included in the print job.

  When drawing information is generated by the image processing unit 33, the engine control unit 31 performs image formation on the paper conveyed from the paper feed table 25 based on the generated drawing information. That is, the print engine 26 functions as an image forming unit. A document on which an image has been formed by the print engine 26 is discharged to a discharge tray 27.

  When the image forming apparatus 1 operates as a scanner, the operation display control unit 34 or the input / output unit is operated in accordance with a user operation on the display panel 24 or a scan execution instruction input from an external PC or the like via the network I / F 28. The control unit 32 transfers a scan execution signal to the main control unit 30. The main control unit 30 controls the engine control unit 31 based on the received scan execution signal.

  The engine control unit 31 drives the ADF 21 and conveys the document to be imaged set on the ADF 21 to the scanner unit 22. Further, the engine control unit 31 drives the scanner unit 22 and images a document conveyed from the ADF 21. If no original is set on the ADF 21 and the original is directly set on the scanner unit 22, the scanner unit 22 takes an image of the set original under the control of the engine control unit 31. That is, the scanner unit 22 operates as an imaging unit.

  In the imaging operation, an imaging element such as a CCD included in the scanner unit 22 optically scans the document, and imaging information generated based on the optical information is generated. The engine control unit 31 transfers the imaging information generated by the scanner unit 22 to the image processing unit 33. The image processing unit 33 generates image information based on the imaging information received from the engine control unit 31 according to the control of the main control unit 30. Image information generated by the image processing unit 33 is stored in a storage medium attached to the image forming apparatus 1 such as the HDD 40. That is, the scanner unit 22, the engine control unit 31, and the image processing unit 33 work together to function as a document reading unit.

  The image information generated by the image processing unit 33 is stored in the HDD 40 or the like as it is according to a user instruction or transmitted to an external device via the input / output control unit 32 and the network I / F 28. That is, the ADF 21 and the engine control unit 31 function as an image input unit.

  Further, when the image forming apparatus 1 operates as a copying machine, the image processing unit 33 generates drawing information based on the imaging information received by the engine control unit 31 from the scanner unit 22 or the image information generated by the image processing unit 33. To do. Based on the drawing information, the engine control unit 31 drives the print engine 26 as in the case of the printer operation.

  Next, the configuration of the print engine 26 according to the present embodiment will be described with reference to FIG. As shown in FIG. 3, the print engine 26 according to the present embodiment includes a configuration in which image forming units 106 of respective colors are arranged along an intermediate transfer belt 105 that is an endless moving unit, and is a so-called tandem type. It is said that. That is, a plurality of image forming units (in order from the upstream side in the transport direction of the intermediate transfer belt 105 along the intermediate transfer belt 105 to which the images formed and superimposed by the image forming units 106 of the respective colors are temporarily transferred. Electrophotographic process unit) 106BK, 106M, 106C, 106Y are arranged.

  The plurality of image forming units 106BK, 106M, 106C, and 106Y have the same internal configuration except that the colors of the toner images to be formed are different. The image forming unit 106BK forms a black image, the image forming unit 106M forms a magenta image, the image forming unit 106C forms a cyan image, and the image forming unit 106Y forms a yellow image. In the following description, the image forming unit 106BK will be described in detail. However, since the other image forming units 106M, 106C, and 106Y are the same as the image forming unit 106BK, the image forming units 106M, 106C, and 106Y are similar to the image forming unit 106BK. As for each of the components, only the symbols distinguished by M, C, and Y are displayed in the drawing in place of the BK attached to each component of the image forming unit 106BK, and the description thereof is omitted.

  The intermediate transfer belt 105 is an endless belt, that is, an endless belt that is stretched between a driving roller 107 and a driven roller 108 that are rotationally driven. The driving roller 107 is driven to rotate by a driving motor (not shown), and the driving motor and the driving roller 107 function as a driving unit that moves the intermediate transfer belt 105 that is an endless moving unit.

  At the time of image formation, the paper 104 stored in the paper feed tray 101 is sent out by the paper feed roller 102 in order from the top and is abutted against the registration roller 103. The registration roller 103 starts to rotate in accordance with the conveyance timing of the toner image transferred onto the intermediate transfer belt 105, thereby causing the abutted sheet to move between the secondary transfer roller 119 and the intermediate transfer belt 105. It is conveyed to a certain secondary transfer unit. In the secondary transfer portion, the toner image formed on the intermediate transfer belt 105 is transferred onto the sheet by the function of the secondary transfer roller 119.

  A registration sensor 104 for detecting a sheet is disposed between the sheet feeding roller 102 and the registration roller 103 in the sheet conveyance path. The register sensor 104 outputs a detection signal according to whether or not a sheet exists at the detection position. Based on the detection signal output from the registration sensor 104, the engine control unit 31 can detect a state where sheets are not conveyed as intended, a state where sheets are conveyed in duplicate, and the like.

  The image forming unit 106BK includes a photoconductor drum 109BK as a photoconductor, a charger 110BK arranged around the photoconductor drum 109BK, an optical writing device 111, a developing device 112BK, a photoconductor cleaner (not shown), and a static eliminator. 113BK and the like. The optical writing device 111 is configured to irradiate the respective photosensitive drums 109BK, 109M, 109C, and 109Y (hereinafter collectively referred to as the photosensitive drum 109) with a laser beam.

  At the time of image formation, the outer peripheral surface of the photosensitive drum 109BK is uniformly charged by the charger 110BK in the dark, and then writing is performed by a laser beam corresponding to the black image from the optical writing device 111. An image is formed. The developing device 112BK visualizes the electrostatic latent image with black toner, thereby forming a black toner image on the photosensitive drum 109BK.

  This toner image is transferred onto the intermediate transfer belt 105 by the action of the transfer unit 115BK at a position (transfer position) where the photosensitive drum 109BK and the intermediate transfer belt 105 are in contact with each other. By this transfer, an image of black toner is formed on the intermediate transfer belt 105. After the transfer of the toner image is completed, unnecessary toner remaining on the outer peripheral surface of the photosensitive drum 109BK is wiped off by the photosensitive cleaner, and then the charge is removed by the charge eliminator 113BK, and waits for the next image formation.

  As described above, the intermediate transfer belt 105 to which the black toner image is transferred by the image forming unit 106BK is conveyed to the next image forming unit 106M side by the rotational drive by the driving roller 107. In the image forming unit 106M, a magenta toner image is formed on the photosensitive drum 109M by a process similar to the image forming process in the image forming unit 106BK, and the toner image is superimposed and transferred onto the already formed black image. Is done.

  The intermediate transfer belt 105 is further conveyed to the next image forming units 106C and 106Y, and a cyan toner image formed on the photosensitive drum 109C and a yellow toner image formed on the photosensitive drum 109Y by the same operation. The toner image is superimposed and transferred. In this way, a full color image is formed on the intermediate transfer belt 105.

  The intermediate transfer belt 105 on which the full-color superimposed image is formed proceeds to the position facing the secondary transfer roller 119 described above, and the toner image formed on the intermediate transfer belt 105 in the secondary transfer portion is secondary to the sheet. Transcribed. Further, the sheet on which the toner image is transferred is discharged to the outside of the image forming apparatus after the image is fixed by the fixing device 116. In the case of double-sided printing in which image formation output is performed on both sides of a sheet, the sheet having a toner image fixed on one side is conveyed to a reversing path, reversed and applied to the registration roller 103 again.

  Next, a control configuration of the print engine 26 by the engine control unit 31 according to the present embodiment will be described. FIG. 4 is a diagram illustrating each part of the print engine 26 controlled by the engine control unit 31 according to the present embodiment. As shown in FIG. 4, the engine control unit 31 includes an optical writing device 111, a developing device 112, a transfer device 115, a secondary transfer roller 119, a paper feed clutch 01, and a paper transport among the modules included in the print engine 26. The print engine 26 is controlled by exchanging signals among the motor 202, the registration clutch 203, and the registration sensor 104.

  The optical writing device 111 executes optical writing on the photosensitive drum 109 by acquiring image information to be output from the engine control unit 31. In this case, the engine control unit 31 functions as an image information output unit that transmits information about an image to be imaged and output for each page. The developing device 112 outputs a developing bias voltage for developing the electrostatic latent image formed on the photosensitive drum 109 in accordance with a control signal from the engine control unit 31.

  The transfer unit 115 outputs a transfer bias voltage for transferring the toner image developed on the photosensitive drum 109 to the intermediate transfer belt 105 in accordance with a control signal from the engine control unit 31. The secondary transfer roller 119 outputs a secondary transfer bias voltage for transferring the toner image transferred onto the intermediate transfer belt 105 to a sheet in accordance with a control signal from the engine control unit 31.

  The paper transport motor 202 rotates in response to a control signal from the engine control unit 31 to rotate the paper feed roller 102 and the registration roller 103. The paper feed clutch 201 switches whether to transmit the power of the paper transport motor 202 to the paper feed roller 102 according to the control of the engine control unit 31. In this case, the engine control unit 31 functions as a paper feed roller drive control unit that controls the rotational drive of the paper feed roller 102. The registration clutch 104 switches whether to transmit the power of the paper transport motor 202 to the registration roller 103 according to the control of the engine control unit 31.

  The registration sensor 104 is a sheet detection sensor that detects a sheet in the sheet feeding path and outputs a detection signal, and outputs a signal based on the presence or absence of the sheet at the detection position shown in FIG. For example, the registration sensor 104 outputs a signal to the engine control unit 31 only when there is a sheet at the detection position. As a result, the engine control unit 31 determines whether or not the sheet is conveyed as intended, and determines that the sheet is conveyed in duplicate. That is, the engine control unit 31 functions as a paper feed success / failure determination unit.

  In such a configuration, the gist of the present embodiment lies in the control of the paper feed clutch 201 and the paper transport motor 202 by the engine control unit 31 and the detection of a paper transport state defect based on the registration sensor 104. Hereinafter, the rotation control of the paper feed roller 102 by the control of the paper feed clutch 201 and the jam detection by the detection signal of the registration sensor 104 in the engine control unit 31 according to the present embodiment will be described.

  FIG. 5 is a timing chart showing the timing of the rotation control and jam detection period of the paper feed roller 102 during the normal operation of the image forming apparatus 1 according to the present embodiment. As shown in FIG. 5, the engine control unit 31 outputs an image signal for each page to the optical writing device 111 at intervals of a period T. After the start of the output of the image signal for each page and after the elapse of the period t, the engine control unit 31 controls the paper feed clutch 201 to transmit the power of the paper transport motor 202 to the paper feed roller 102 to feed the paper. The rotation of the roller 102 is started and the paper feed from the paper feed tray 101 is started.

  In other words, the engine control unit 31 starts rotational driving of the paper feed roller 102 that feeds paper from the paper feed tray 101 that is a paper storage unit in response to the start of transmission of image information for each page.

After the rotation of the paper feed roller 102 is started, the period t ₁ is a detection period for confirming that the paper is fed as intended. If the detection signal from the registration sensor 104 is not input during the time period t _1, the engine control unit 31 performs the paper feed error detection as the paper feed is not performed properly, the image forming apparatus 1 In the controller 20, control according to the paper feed error detection is executed.

FIG. 6 is a timing chart showing the control timing in the case where there is a possibility that the paper feed roller is worn and there is a possibility of delay in paper conveyance in the prior art. In the case of FIG. 6, the engine control unit 31 starts outputting the image signal for each page and then starts the rotation of the paper feed roller 102 after a period shorter by t ₂ than the period t to feed the paper feed tray 101. Feeding from the printer starts. During the period t ₂ minutes hastened start timing of the sheet feed takes longer time to perform sheet feeding error detection.

  According to such control, even in the case where there is a delay in the conveyance of the paper due to the wear of the paper feed roller, in the prior art, a state in which the operation of the apparatus is stopped due to the paper feed error detection is performed. However, when the top stacked sheet in the sheet feeding tray 101 is fed by the sheet feeding roller 102, the next sheet is fed from the sheet feeding tray to the registration roller 103 side by friction between the sheets. A state called “bringing” may occur.

In the example of FIG. 6, the period from the start of the input of the image signal in each page to the start of paper feeding is adjusted to be shorter than in the case of FIG. 5, but the image signal of each page is adjusted. since the input interval unchanged, as a result, after completing the feeding of one page, the period t ₃ until the start of feeding of the next page, is shorter than the case of FIG. 5 . Since the transport speed by the paper feed roller 102 is generally faster than the transport speed by the registration roller 103, the fed paper catches up with the paper of the previous page when the above-mentioned feed state occurs. It can happen.

  When the fed paper catches up with the paper of the previous page, the paper of the next page reaches the detection position of the registration sensor 104 before the paper of the previous page passes the detection position of the registration sensor 104. As a result, the registration sensor 104 remains outputting the detection signal.

  The engine control unit 31 controls the rotation of the registration roller 103 by controlling the registration clutch 203 in accordance with the detection signal of the registration sensor 104. For this reason, when the next page of paper catches up with the previous page of paper, the engine control unit 31 cannot determine the timing for stopping the rotation of the registration roller 103, and as a result, the next page of paper is moved to the previous page. It is transported along with the paper on the page, leading to jamming.

  In order to solve such a problem, in the present embodiment, rotation control of the paper feed roller 102 in a state where the paper feed roller 102 is worn is performed based on the timing shown in FIG. That is, FIG. 7 is a timing chart showing the timing at which the engine control unit 31 controls the driving of the paper feed roller 102 in a state where the paper feed is expected to be delayed due to deterioration of the paper feed roller. In the example of FIG. 7, as in the case of FIG. 5, the engine control unit 31 starts the rotation of the paper feed roller 102 after the elapse of the period t after starting input of an image signal in each page.

Then, after starting the rotation of the paper feed roller 102, the period t ₂ minutes period longer than the period t ₁ in FIG. 5, the sheet feeding error detection period. That is, the engine control unit 31 starts the rotation of the paper feed roller 102, and when the detection signal is not input from the registration sensor 104 within a period of t ₁ + t ₂ that is extended by t ₂ from t ₁ , Is determined not to be fed as intended. As a result, even if the paper feed roller 102 is worn out and paper feed is delayed, it is determined that a paper feed error is detected and the apparatus is stopped by extending the paper feed error detection period. Can be prevented.

Furthermore, the engine control unit 31 according to the present embodiment increases the jam detection period by t ₂ minutes, in other words, increases the paper feeding period for one page by t ₂ minutes, and the next page image. The timing for starting the formation output, that is, the timing for starting the input of the image signal for the next page is delayed by t ₂ , and the image signal for each page is output to the optical writing device 111 at intervals of the period T + t ₂ . That is, the engine control unit 31 starts transmission of the image information of one page and then extends the timing of starting transmission of the image information of the next page according to the period in which the paper feed error detection period is extended.

Such control, in the example of FIG. 7, after completing the feeding of the one page, time t ₄ before the start of feeding of the next page, as the period t ₃ in FIG. 6 It will not be shortened. Therefore, as described above, the fed paper can be prevented from catching up with the paper of the previous page.

In the example of FIG. 7, the period from when the engine control unit 31 starts inputting the image signal to when the rotation of the paper feed roller 102 starts is the period t as in the case of FIG. 5. As an example, in consideration of the arrival timing of the sheet to the registration roller 103, it may be set to t−t ₂ as shown in FIG. Also in this case, as shown in FIG. 7, the same effect as described above can be obtained by delaying the input start timing of the image signal of the next page by t2 by setting the paper feed error detection period to t ₁ + t _2. Is possible.

  Next, a description will be given of determination when the engine control unit 31 according to the present embodiment functions as a paper feed roller deterioration determination unit and switches from the control shown in FIG. 5 to the control shown in FIG. FIG. 8 is a diagram illustrating determination items for determining switching to the control as illustrated in FIG. 7, that is, determination items for determining that the paper feed roller 102 is deteriorated, and setting values necessary for the determination. .

  As shown in FIG. 8, the determination items according to the present embodiment include “registration arrival delay time”, “number of sheets fed”, “cumulative rotation distance”, and “sheet feeding error probability”. “Registration arrival delay time” is a period during which the registration sensor 104 detects a sheet and outputs a detection signal after the sheet feeding roller 102 starts rotating and starts feeding a sheet. This is a determination based on the delay time when it is later than (registration arrival reference period).

The resist reaches a reference period is a shorter period than t ₁ shown in FIG. For the determination item of “registration arrival delay time”, “delay period threshold value” is set, and after the engine control unit 31 starts rotation of the paper feed roller 102, the registration sensor 104 outputs a detection signal. The period until output is accumulated by acquiring a period delayed from the registration arrival reference period (hereinafter referred to as “detection delay period”) and storing it in the storage medium. And the engine control part 31 calculates the average value of the past several detection delay periods, and when the average value exceeds the said delay period threshold value, it determines switching to control as shown in FIG. .

  The “number of sheets fed” is set based on the idea that minute wear occurs every time the sheet feed roller 102 feeds sheets from the sheet feed tray 101, and the number of sheets fed by the sheet feed roller 102 is set. This is an item for determining switching to the control as shown in FIG. 7 when the “sheet count threshold” is exceeded. Therefore, the engine control unit 31 counts the number of sheets fed by the sheet feed roller 102, and makes a determination by comparing the count value and the sheet feed number threshold each time the sheet is fed by the sheet feed roller 102.

  The “cumulative rotation distance” is based on the idea that minute wear occurs each time the paper feed roller 102 rotates to feed paper from the paper feed tray 101, so that the roller surface is conveyed by the rotation of the paper feed roller 102. This is an item for determining switching to control as shown in FIG. 7 when the distance exceeds the set “rotational distance threshold”. For this reason, the engine control unit 31 counts the conveyance distance of the roller surface due to the rotation of the paper feed roller 102, and each time the paper is fed by the paper feed roller 102, the determination is made by comparing the count value with the rotation distance threshold. I do.

The “paper feed error probability” is set as the “paper feed error probability” in which the detection signal from the registration sensor 104 is not output within the paper feed error detection period as indicated by t ₁ in FIG. This is an item for determining switching to control as shown in FIG. 7 when the error probability threshold is exceeded. Therefore, the engine control unit 31 counts the number of times paper is fed from the paper feed tray 101 and the number of times a paper feed error has occurred, and calculates a paper feed error probability based on the count result. Each time the paper is fed by the paper feed roller 102, a determination is made by comparing the calculation result of the paper feed error probability with the “paper feed error probability threshold”.

The engine control unit 31 according to the present embodiment individually determines each determination item as shown in FIG. 8 and when it is determined from at least one item that the paper feed roller 102 has deteriorated. Switches to control as shown in FIG. It is also possible to set a sub-stage threshold value for one determination item. In such a case, for example, "the number of fed sheets" and each time the count value of "cumulative rotational distance" or the like reaches the threshold value stages each, by extending the sheet feeding error detection period by t _2, sheet feeding error Thus, it is possible to avoid a state in which the apparatus operation stops.

Figure 9 is a timing chart showing a further state of the sheet feeding error detection period was extended t ₂ minutes from the state shown in FIG. As shown in FIG. 9, the same effect as described above can be obtained by further extending the input start interval of the image signal of each page as T + 2t ₂ in accordance with the extension of the paper feed error detection period. is there. In other words, the engine control unit 31 sets the paper feed error detection period according to the threshold value used in the deterioration determination among a plurality of different threshold values set for the information on the deterioration determination target of the paper feed roller. Wide adjustment is possible by changing the extension period when extending.

  Further, by setting a sub-stage threshold value for one determination item, it is possible to speed up the control switching determination process and to improve the reliability of the determination by combining a plurality of determinations. Such an example will be described below.

  FIG. 10 is a flowchart showing an operation in the case of setting a sub-stage threshold value for one determination item and determining by combining a plurality of determinations. In the example of FIG. 10, “sheet feeding number” and “sheet feeding error probability” are set as determination items, and a case where a two-stage threshold is set for the number of feeding sheets is taken as an example.

  As shown in FIG. 9, when the engine control unit 31 controls the paper feed clutch 201 to start paper feeding (S1001), the engine control unit 31 counts up the number of fed paper sheets each time paper is fed (S1002). As a result of the count-up, the number of paper sheets to be fed is the lower threshold value of the first stage among the paper sheet number threshold values set in two stages, that is, a severe condition for determining that the paper feed roller has not deteriorated. If it is less than the threshold value (S1003 / YES), the engine control unit 31 determines that there is no possibility of paper feed delay due to wear of the paper feed roller, and ends the control timing switching judgment operation.

  In this way, by setting a threshold value that is stricter than the threshold value with which the feed roller wear is surely determined, it is determined that there is no possibility of a delay in feed due to wear of the feed roller at an earlier timing. And the processing speed can be increased.

  On the other hand, if the number of fed sheets is equal to or greater than the lower threshold of the first stage among the thresholds of the number of fed sheets set in two stages (S1003 / NO), the engine control unit 31 wears the feed rollers. It is determined that there is a possibility of paper feed delay. Then, the engine control unit 31 calculates a paper feed error probability (S1004) and compares it with the set paper feed error probability threshold (S1005). That is, when the engine control unit 31 determines that there is a possibility of deterioration of the paper feed roller based on a strict threshold set for information on a certain determination target, the paper feed based on the information on another determination target. Judge roller deterioration. As a result, the accuracy of deterioration determination can be improved.

  As a result of the comparison in S1005, when the calculated paper feed error probability is less than the set paper feed error probability threshold (S1005 / YES), the engine control unit 31 at least in terms of the paper feed error probability It is determined that there is no possibility of a paper feed delay due to wear of the 102, and the second stage out of the count value of the number of paper feeds counted for each paper feed and the paper feed sheet number threshold set in two stages. Comparison with the higher threshold is performed (S1006).

  As a result of the determination in S1006, if the count value of the number of fed sheets is less than the higher threshold value, the engine control unit 31 determines that there is no possibility of delay in feeding due to wear of the feeding roller, and the control timing The switching determination operation is terminated.

  On the other hand, if the paper feed error probability is greater than or equal to the threshold in the determination of S1005 (S1005 / NO), or if the count value of the number of fed paper is greater than or equal to the higher threshold in the determination of S1006 (S1006 / NO), the engine control unit 31 determines that the paper feed roller 102 has deteriorated due to wear, and performs control according to the deterioration (S1007).

Processing of S1007, as described in FIG. 7, another processing for switching to the control was extended t ₂ minutes a prolonged period set the paper feed error detection period, through the display panel 24 or the like, the paper feed roller 102 This is processing for notifying the user that replacement is necessary because wear has occurred. Further, when the paper feed roller detection period is sequentially extended as described with reference to FIG. 9 using the sub-stage threshold, the paper feed error detection period is extended according to the threshold used as a criterion.

  In FIG. 10, as an example, the case of using the determination items of “number of sheets to be supplied” and “paper supply error probability” has been described as an example, but other determination items can be similarly applied. For example, in S1002 and S1006, the “cumulative rotation distance” is compared with the first and second thresholds, and in S1005, the “feed error probability” is compared with the threshold. Variations such as performing are possible.

  The determination items described with reference to FIG. 8 are merely examples, and other determination items may be adopted as long as the content can determine deterioration due to wear of the paper feed roller.

  As described above, according to the image forming apparatus 1 according to the present embodiment, it is possible to suitably prevent the occurrence of a paper feed error in a state where a roller for transporting paper is worn.

  In the above-described embodiment, the case of the secondary transfer type in which the toner image is transferred onto the sheet after the toner image is transferred onto the intermediate transfer belt 105 has been described as an example. In addition, the present invention can be applied to the direct transfer type in which the intermediate transfer belt 105 functions as a transport belt for transporting paper and the toner image is directly transferred from the photosensitive drum 109 to the paper. Is possible.

1 image forming apparatus,
10 CPU,
11 RAM,
12 ROM,
13 engine,
14 HDD,
15 I / F,
16 LCD,
17 Operation part,
18 Bus,
20 controller,
21 ADF,
22 Scanner unit,
23 Output tray,
24 display panels,
25 Paper feed table,
26 print engine,
27 Output tray,
28 Network I / F,
30 Main control unit,
31 engine control unit,
32 Input / output control unit,
33 Image processing unit,
34 Operation display control unit,
101 paper feed tray,
102 paper feed roller,
103 registration rollers,
104 resist sensor,
105 Intermediate transfer belt,
106BK, 106C, 106M, 106Y Image forming unit,
107 driving roller,
108 driven roller,
109BK, 109C, 109M, 109Y photosensitive drum,
110BK charger,
111 optical writing device,
112BK, 112C, 112M, 112Y Developer,
113BK, 113C, 113M, 113Y
115BK, 115C, 115M, 115Y transfer device,
116 fixing device,
119 Secondary transfer roller,
201 Paper supply clutch 202 Paper conveyance motor 203 Registration clutch

JP 2008-26690 A

Claims (9)

An image formation control device for controlling an image formation output for forming an image on a sheet conveyed by a roller,
An image information output unit that transmits image information of an image to be output for each page to an image forming unit that executes image formation output;
A paper feed roller drive control unit that starts rotation of a paper feed roller that feeds the paper from a storage unit in which the paper is stored in response to the start of transmission of the image information for each page;
Based on an output signal of a paper detection sensor that detects the paper in the paper feed path and outputs a detection signal, it is determined whether or not the paper feed is completed within a predetermined detection period. A paper success / failure determination unit,
The paper feed success / failure determination unit determines whether the paper feed of the paper is completed by extending the detection period in a state where the paper feed of the paper is expected to be delayed due to deterioration of the paper feed roller. Judging
The image information output unit transmits image information of one page and then transmits image information of the next page in a state where the paper feeding of the paper is expected to be delayed due to deterioration of the paper feed roller. An image forming control apparatus characterized in that the start timing is delayed according to a period obtained by extending the detection period. A paper feed roller deterioration determination unit that determines that the paper feed is expected to be delayed due to deterioration of the paper feed roller;
The paper feed roller deterioration determination unit is in a state where it is predicted that paper feed of the paper will be delayed due to deterioration of the paper feed roller based on a plurality of different threshold values set for information to be determined. Judging
The image forming control apparatus according to claim 1, wherein the paper feed success / failure determination unit changes a period for extending the detection period in accordance with a threshold used for determination among the plurality of different thresholds.   The image forming control apparatus according to claim 2, wherein the paper feed roller deterioration judgment unit uses a count value of the number of sheets fed by the paper feed roller as the information to be judged.   The image forming apparatus according to claim 2, wherein the paper feed roller deterioration determining unit uses, as the determination target information, a count value of a distance that the paper is transported by the rotation of the paper feed roller. Control device.   3. The paper feed roller deterioration determining unit uses information of a period delayed from a timing at which the paper is supplied as a predetermined reference as the determination target information. Image formation control device.   3. The image according to claim 2, wherein the paper feed roller deterioration determination unit uses, as the determination target information, information related to the number of times the paper supply is not completed within a predetermined detection period. Formation control device.   The paper feed roller deterioration determining unit, when a strict threshold for determining that the paper feed roller is not deteriorated among a plurality of different thresholds set for the determination target information is satisfied, It is immediately determined that the paper feed roller is not deteriorated, and if the strict threshold is not satisfied, the deterioration of the paper feed roller is determined based on information of another determination target. The image formation control device according to claim 2.   An image forming apparatus comprising the image forming control apparatus according to claim 1. A control method of an image forming apparatus for controlling the conveyance of the paper in an image forming control apparatus for forming an image on the paper conveyed by a roller,
For each page, image information of an image to be output is transmitted to an image forming unit that executes image formation output.
In response to the start of transmission of the image information for each page, rotation driving of a paper feed roller that feeds the paper from a storage unit that stores the paper is started.
Based on an output signal of a paper detection sensor that detects the paper in the paper feed path and outputs a detection signal, it is determined whether or not the paper feed is completed within a predetermined detection period;
In a state where the paper feed is expected to be delayed due to the deterioration of the paper feed roller, it is determined whether or not the paper feed is completed by extending the detection period. A method for controlling an image forming apparatus, comprising: delaying a timing at which transmission of image information of the next page is started after transmission of image information in accordance with a period obtained by extending the detection period.

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