Image forming apparatus, display method, and program

Abstract

To provide an image forming apparatus that appropriately deals with sliding of a recording medium.SOLUTION: The present invention relates to an image forming apparatus in which a transfer unit transfers an image formed on an image carrier to a recording medium. The image forming apparatus has: a paper feed unit that feeds the recording medium from a storage unit storing the recording medium to the transfer unit; and a display unit that, when a feeding time from the start of feeding until detection of the recording medium in the transfer unit exceeds a threshold, displays a message indicating that a feeding roller should be cleaned.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to an image forming apparatus, a display method, and a program. [Background technology]

[0002] In image forming devices that form images on sheet-like recording media such as paper, the timing of the image to be transferred to the recording media may differ from the timing of feeding the recording media to the transfer position due to "slippage" of the recording media. The image forming device judges a delay in feeding due to such "slippage" of the recording media as a jam and stops operation. In other words, even if the recording media is not stuck in the feeding path, i.e. a jam, the user must open and close the cover of the image forming device to remove the jam, resulting in "downtime" when the image forming device cannot be used.

[0003] There is a known technology for reducing such downtime (see, for example, Patent Document 1). In Patent Document 1, when a delay in feeding due to slippage of the recording medium is detected, transfer is stopped once, the paper is advanced to a specified position, and when the recording medium is detected by a sensor, image formation is performed again, and if the recording medium is not detected within a certain period of time, it is determined to be a jam, thereby reducing downtime. Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the conventional technology, the image forming device must form an image again, which consumes more toner than usual and extends the travel distance of each part (reducing the maintenance lifespan).In addition, depending on the model, if the image is repeatedly formed again, it is assumed that a jam has been detected, so the user must remove the jam even if a jam has not actually occurred.

[0005] In view of the above-mentioned problems, the present invention provides a technique for appropriately dealing with slippage of a recording medium. [Means for solving the problem]

[0006] The present invention is an image forming device that transfers an image formed on an image carrier to a recording medium in a transfer unit, and has a feeding unit that feeds the recording medium from a storage unit in which the recording medium is stored to the transfer unit, and a display unit that displays a message that the feed roller should be cleaned when the feeding time from the start of feeding to the detection of the recording medium in the transfer unit exceeds a threshold value. Effect of the Invention

[0007] The image forming apparatus can appropriately deal with slippage of the recording medium. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a configuration diagram showing an embodiment of an image forming apparatus, and is a configuration diagram showing an example of a tandem type image forming apparatus in which a plurality of image carriers are arranged in parallel. [Diagram 2] FIG. 2 is a diagram illustrating an example of a hardware configuration of an image forming apparatus. [Diagram 3] FIG. 2 is a diagram illustrating an example of a functional configuration of an image forming apparatus. [Figure 4] FIG. 1 is a flowchart illustrating an example of a flow of image formation performed by an image forming apparatus, which is shown as a comparative technique for explaining the present embodiment. [Diagram 5] FIG. 1 is a flowchart illustrating an example of a flow of an image forming process executed in the image forming apparatus according to the embodiment. [Figure 6] 13 is a diagram illustrating an example of a notification screen for a user displayed on a display unit. [Figure 7] 13 is a diagram illustrating an example of a notification screen for a user that forced printing is possible. [Figure 8] FIG. 13 is a flowchart illustrating an example of a process in which a display unit displays a message to clean the paper feed roller when the occurrence rate of image retransmissions in the same job exceeds an occurrence rate determination threshold. [Figure 9]FIG. 13 is a flowchart illustrating an example of a process in which a display unit displays a message to clean the paper feed rollers when the total downtime caused by image retransmissions in the same job exceeds a downtime determination threshold. [Figure 10] FIG. 13 is a diagram showing an example of a notification condition setting screen displayed on a display unit. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An image forming apparatus and a display method performed by the image forming apparatus will be described below as an example of an embodiment of the present invention with reference to the drawings.

[0010] <Outline of the embodiment> In the case of an image-first machine in which an image is prepared before the paper is transported, delays (slippage) of the paper may occur due to paper dust adhering to the paper feed roller, which may extend the paper feed time, and the paper may not arrive in time for the image on the intermediate transfer belt to reach the transfer position. Therefore, some image forming devices are equipped with an "image resending" function that stops the transfer once, advances the paper to a specified position, and forms the image again when the paper is detected by a sensor.

[0011] As mentioned above, image resending has the disadvantages of consuming more toner than usual and extending the travel distance of each part (reducing the maintenance lifespan). Also, some image forming devices "determine a jam when image resending is performed for N consecutive sheets," and even if the disadvantages of increased toner consumption and travel distance can be reduced, the user is forced to remove the jam (the user does not know that the jam detection is due to image resending).

[0012] Therefore, the image forming apparatus of this embodiment detects the occurrence of a paper delay (slippage), and if a certain condition is met, it stops printing once and notifies the user by a pop-up or the like that the paper feed roller should be cleaned. This eliminates the need for the user to remove the jam. It also reduces the disadvantages of increased toner consumption and mileage. In addition, since the user can know that the image resend function has been activated, the image forming apparatus can urge the user to clean the paper feed roller. Furthermore, by temporarily stopping printing, when the image forming apparatus is printing a large volume, it is possible to urge the user to stop printing and perform cleaning, thereby shortening the time until printing is completed.

[0013] <Terminology> Cleaning the paper feed rollers is, for example, a task of wiping the entire paper feed rollers with a cloth that has been soaked in water and wrung out tightly while rotating the paper feed rollers. The user then wipes them off with a dry cloth. Note that the method of manufacturing the paper feed rollers does not matter as long as it reduces slippage of the paper P. Also, if there are parts other than the paper feed rollers that cause slippage of the paper P, the image forming apparatus 100 may display a message to the effect that the parts will be cleaned.

[0014] The threshold value is a value for detecting, based on the feeding time, the occurrence of a delay (slippage) of the paper P. In this embodiment, the threshold value is explained by the term "registration restart time."

[0015] <Configuration example of image forming apparatus> Next, an image forming apparatus according to the present embodiment will be described with reference to the drawings. The image forming apparatus according to the present embodiment is an apparatus that forms an image by applying a developer or ink to a recording medium such as paper, an OHP sheet, thread, fiber, textile, leather, metal, plastic, glass, wood, or ceramics as a "recording medium". In the following description, "image formation" refers not only to applying an image having meaning such as a character or figure to a recording medium, but also to applying an image having no meaning such as a pattern to a recording medium. In addition, the "sheet-like body" is not limited to paper (paper), but also includes OHP sheets, textiles, etc., and means a medium to which a developer or ink can be applied, and includes those called recording media, recording paper, and recording paper. In the following embodiment, the sheet-like body will be described as "paper P". In addition, the dimensions, materials, shapes, and relative positions of each component are examples, and are not intended to limit the scope of the present embodiment unless otherwise specified.

[0016] FIG. 1 is a configuration diagram showing an embodiment of an image forming apparatus equipped with an image formation control device according to the present embodiment, and is a configuration diagram showing an example of a tandem type image forming apparatus in which a plurality of image carriers 2 are arranged in parallel. As shown in FIG. 1, inside the image forming apparatus 100, four process units 1C, 1M, 1Y, and 1K are arranged as image forming units (imaging devices) for forming images of each color of cyan (C), magenta (M), yellow (Y), and black (K). The four process units 1C, 1M, 1Y, and 1K are all almost the same configuration except that the toner colors are different. In the following description, for convenience, C (cyan), M (magenta), Y (yellow), and K (black) are added as suffixes after the numbers indicating the components in accordance with the toner colors of the images to be formed. In addition, in the case of general description, these suffixes are omitted as appropriate.

[0017] As shown in Fig. 1, each of the process units 1 (C, M, Y, K) includes a drum-shaped image carrier 2 (2C, 2M, 2Y, 2K). The four image carriers 2 are arranged in parallel at equal intervals in the moving direction of an intermediate transfer belt 16 in the image forming section. When the image forming apparatus 100 is in operation, the peripheral surface of each of the image carriers 2 rotates in the same direction as the conveying direction of the intermediate transfer belt 16 that it faces, as a result of the drive force being transmitted from a drive source. A toner image is formed on the image carrier 2 by an image creation process using laser light inside the process unit 1.

[0018] A transfer device 15 is disposed below the image carriers 2. The transfer device 15 has an endless intermediate transfer belt 16, one end of which is wound around a driven roller 17 and the other end of which is wound around a transfer drive roller 18. The intermediate transfer belt 16 runs in the direction of arrow A as the transfer drive roller 18, which is driven by a drive source, rotates, so that the surface of each image carrier 2 comes into contact with the upper surface of the intermediate transfer belt 16. Four primary transfer rollers 19 (Y, C, M, K) are provided on the inner periphery of the intermediate transfer belt 16 so as to face each image carrier 2.

[0019] A belt cleaning device 21 constituting an image removal unit is provided on the outer periphery near the right end of the intermediate transfer belt 16. The belt cleaning device 21 is a device that wipes away unnecessary toner remaining on the surface of the intermediate transfer belt 16, paper powder, and other foreign matter.

[0020] A secondary transfer roller 20 constituting a transfer section is provided on the outer periphery of the intermediate transfer belt 16 at a position facing the transfer drive roller 18 with the intermediate transfer belt 16 sandwiched therebetween. The secondary transfer roller 20 abuts against the intermediate transfer belt 16 at a position facing the transfer drive roller 18, forming a secondary transfer nip as a secondary transfer section. The secondary transfer nip electrostatically transfers a toner image formed and carried on the intermediate transfer belt 16 to the paper P by applying a bias while paper P, which is a recording medium, passes between the intermediate transfer belt 16 and the secondary transfer roller 20.

[0021] The paper feed tray 30 is a storage section that stores a plurality of sheets of paper P in a stacked state in its internal space. A bottom plate 46 for placing the sheets of paper P in a stacked state is disposed on the bottom surface of the internal space of the paper feed tray 30. One end of the bottom plate 46 in the longitudinal direction is supported by a support shaft so as to be freely rotatable, and the other end is capable of swinging up and down. The bottom plate 46 is constantly biased upward by a biasing member such as a spring.

[0022] A feed roller 47 is disposed as a rotating member on the end side of the feed tray 30 where the bottom plate 46 swings. This feed roller 47 comes into contact with the top of the stack of sheets P placed in a stacked state on the feed tray 30, and can feed out the topmost sheet P. The feed roller 47 does not necessarily have to be in the form of a roller, as long as it can feed the sheets P in a predetermined direction. For example, an endless rotating belt stretched between two rollers may be used instead of the feed roller 47.

[0023] A registration sensor 31 capable of detecting the leading edge of the paper P is disposed downstream of the paper feed roller 47 in the feeding direction. Further, a registration roller pair 32 serving as a medium standby unit for temporarily stopping the paper P is disposed downstream of the registration sensor 31 in the feeding direction. The registration sensor 31 detects that the paper P has arrived at the secondary transfer nip, and the registration roller pair 32 causes the paper P to wait.

[0024] The registration roller pair 32 is located immediately upstream of the intermediate transfer belt 16, and stops the paper P to temporarily slacken it in order to precisely align the toner image carried on the intermediate transfer belt 16 with the leading edge position of the paper in the transfer section. The registration roller pair 32 sends the paper P, which has been stopped temporarily, to the secondary transfer nip section at a predetermined timing just before the toner image formed and carried on the intermediate transfer belt 16 is transferred to the paper P in the secondary transfer nip section. The paper feed tray 30, the paper feed roller 47, and the registration roller pair 32 form a feed section.

[0025] A fixing device 34 is disposed further upstream in the feeding direction than the secondary transfer nip portion formed by the secondary transfer roller 20 and the transfer drive roller 18. The fixing device 34 includes a fixing roller 34a containing a heat source such as a halogen lamp, and a pressure roller 34b that rotates while contacting the fixing roller 34a with a predetermined pressure. The fixing device 34 may have another configuration, such as an endless rotating belt or an IH heating type.

[0026] <Basic printer operations> Next, a description will be given of the basic operation of the image forming apparatus 100. In Fig. 1, when the paper feed roller 47 of the paper feed tray 30 rotates in response to a feed start signal from the printer control unit, only the topmost paper P of the paper P stacked on the bottom plate 46 of the paper feed tray 30 is separated from the paper P below it and sent out.

[0027] When the leading edge of the paper P is detected by the registration sensor 31, the paper P is fed using the feeding timing as a trigger until a predetermined slack is formed in the secondary transfer nip portion of the registration roller pair 32, thereby correcting the leading edge skew of the paper P.

[0028] Next, the image forming operation of the image forming apparatus 100 will be described. A visible image formed on the image carrier 2K is primarily transferred to the surface of the intermediate transfer belt 16, which moves in synchronization with the image carrier 2K, by the transfer action of the positively charged primary transfer roller 19. Such operations of latent image formation, development, and primary transfer are sequentially performed in all process units 1 (C, M, Y, K) in accordance with the image data, and a four-color toner image in which the toner images of cyan C, magenta M, yellow Y, and black K are sequentially superimposed on each other is carried on the surface of the intermediate transfer belt 16. This four-color toner image is transported together with the intermediate transfer belt 16, whose surface moves in the direction of arrow A.

[0029] When each color toner image is transferred to the intermediate transfer belt 16, the pair of registration rollers 32 and the paper feed roller 47 start driving, and the paper P is fed to the secondary transfer roller 20, which is the transfer position, so that the timing matches with the toner image transferred to the intermediate transfer belt 16. Note that the pair of registration rollers 32 and the paper feed roller 47 do not necessarily start driving at the same time. Also, in addition to the pair of registration rollers 32 and the paper feed roller 47, a feed roller for feeding the paper P may be provided. The secondary transfer roller 20 is positively charged, and the toner image on the intermediate transfer belt 16 is transferred to the fed paper P by the secondary transfer nip portion of this secondary transfer roller 20. Residual toner and foreign matter on the surface of the intermediate transfer belt 16 are removed by the belt cleaning device 21 in preparation for the next image creation and transfer process.

[0030] After the toner image is transferred, the paper P is sent to a fixing device 34. The paper P sent to the fixing device 34 is sandwiched between a fixing roller 34a and a pressure roller 34b, and the unfixed toner image is fixed to the paper P by heating and pressing it.

[0031] <Hardware configuration of image forming device> Next, a hardware configuration for controlling a control system of the image forming apparatus according to this embodiment will be described with reference to Fig. 2. The hardware configuration of the image forming apparatus shown in Fig. 2 is an example applied to the image forming apparatus 100.

[0032] 2, in the image forming control device according to this embodiment, a UART (Universal Asynchronous Receiver Transmitter) 57, a CPU (Central Processing Unit) 58, a ROM (Read Only Memory) 59, a RAM (Random Access Memory) 60, an NVRAM (Non-Volatie Random Access Memory) 61, an operation panel I / F 62, an I / O 65, and an image processing IC 66 are interconnected via a system bus 64. The ROM 59, the RAM 60, and the NVRAM 61 constitute a storage unit of the image forming device 100 according to this embodiment.

[0033] An operation panel 63 operated by a user is connected to the operation panel I / F 62, and a controller 67 is connected to the image processing IC 66. In addition, the I / O 65 is connected to a registration sensor 31 that detects that the paper P is being fed, a feed motor 69 that rotates and drives the paper feed roller 47, a transfer motor 70 that rotates and drives the transfer drive roller 18, a photoconductor motor 71 that rotates and drives the image carrier 2, and a temperature and humidity sensor 72 that detects the temperature and humidity of the paper P.

[0034] An operation panel 63 is connected to the CPU 58 via an operation panel I / F 62. The operation panel 63 is equipped with a display unit 106 and an input unit, functions as a user interface, and is used to set the printer mode and the like. The operation panel I / F 62 exchanges data between the CPU 58 and the operation panel 63. In addition, a controller 67 is connected to the CPU 58 via an image processing IC 66. The CPU 58 obtains printing conditions such as the thickness of the paper to be printed from the controller 67.

[0035] The CPU 58 is a control unit that controls the entire image forming apparatus, and generally controls access to various devices connected to a system bus 64 based on a control program stored in a ROM 59. The CPU 58 controls input / output of the registration sensor 31, the feed motor 69, the transfer motor 70, the photoconductor motor 71, and the temperature / humidity sensor 72, which are connected via an I / O 65. That is, the CPU 58 executes the control program for the image forming apparatus stored in the ROM 59.

[0036] The CPU 58 executes control related to the image forming process such as measuring the feeding time of the paper P, detecting a delay in the feeding time, re-forming the image, and restarting registration (re-feeding) in accordance with commands constituted by the control program and control data.

[0037] The ROM 59 is a read-only non-volatile memory, and stores the control programs and control data used by the CPU 58.

[0038] The RAM 60 is a volatile memory that allows high speed reading and writing of information, and is used as a work frame memory for expanding recorded data and storing environmental data.

[0039] The NVRAM 61 is a readable and writable non-volatile memory, and stores information about the image forming apparatus used by the control program.

[0040] <Functional configuration of image forming apparatus 100> Next, the functional configuration of the image forming apparatus 100 will be described with reference to Fig. 3. As shown in Fig. 3, the image forming apparatus 100 includes a control unit 101, an image creation process unit 102, a fixing unit 103, an image writing control unit 104, an operation unit 105, an I / F unit 107, an image retransmission control unit 108, a jam detection unit 109, a registration monitoring unit 110, and a determination unit 111. Each of these units of the image forming apparatus 100 is a function or means realized by the CPU 58 in Fig. 2 executing commands of a program expanded in the RAM 60.

[0041] The control unit 101 controls each of the functional blocks shown in FIG. 3 in a coordinated manner so that a series of operations for image formation is performed.

[0042] The image creation process unit 102 creates a toner image by electrophotography from image data sent from a terminal device such as a PC (Personal Computer) operated by a user or image data read by a scanner, and transfers the toner image onto paper P. Furthermore, if the image creation process unit 102 detects misalignment during printing, it corrects it.

[0043] The fixing unit 103 applies heat and pressure to the paper P onto which the toner image has been transferred by the image creation process unit 102, thereby fixing the toner image onto the paper.

[0044] The image writing control unit 104 converts the image data sent from the I / F unit 107 into control signals for each color included in the process unit 1 , and controls the writing of a latent image onto the image carrier 2 .

[0045] An operation unit 105 accepts user input to the image forming apparatus using hard keys or soft keys on an operation screen displayed on a touch panel.

[0046] The display unit 106 displays an operation screen related to image formation and the status of the image forming apparatus on a touch panel, and when an error occurs, displays the content of the error and a method for solving the error to the user. The display unit 106 may provide an operation screen to the terminal device by a Web application or the like.

[0047] The I / F unit 107 communicates with a terminal device that issues a print request to the image forming apparatus 100. The I / F unit 107 transmits image data sent from the terminal device to the control unit 101 and issues a print request to the image forming apparatus 100.

[0048] When a delay (slippage) of the paper P occurs, the image retransmission control unit 108 performs control (image retransmission control) such as having the image creation process unit 102 re-form the image and controlling the timing of feeding the delayed paper P to execute the image creation process again.

[0049] When the registration sensor 33 does not detect the paper P until a predetermined jam detection time has elapsed since the start of paper feeding, the jam detection unit 109 detects a jam of the paper P. Even if a jam of the paper P is detected, there are cases where a jam does not actually occur.

[0050] The registration monitoring unit 110 measures the feeding time of the paper P from the start of the image forming process in the image forming process unit 102, and monitors whether or not the registration sensor 31 detects the paper P by the time registration is resumed.

[0051] When an image retransmission occurs, the determination unit 111 determines whether or not a condition for notifying the user to clean the paper feed rollers is satisfied.

[0052] <Image formation process> Next, an image forming process to be compared with this embodiment will be described with reference to Fig. 4. Fig. 4 is a flow chart showing the flow of image formation performed by image forming apparatus 100, which is shown as a comparative technique for explaining this embodiment.

[0053] The user can switch between enabling and disabling the image retransmission function. The user sets in advance whether the image retransmission function is enabled or disabled for a specific screen displayed by the display unit 106. Whether the image retransmission function is enabled or disabled is stored in the image retransmission control unit 108.

[0054] When the print process is started in the image forming apparatus 100, each motor is started, and the control unit 101 starts the image forming process in the process unit 1 (S401).

[0055] The registration monitoring unit 110 starts measuring the registration restart time (S402). The registration restart time is a time for determining whether or not to perform image retransmission control (whether or not slippage of the paper P has occurred).

[0056] Next, the control unit 101 starts the paper feed process (S403). By the control of the control unit 101, the paper feed roller 47, to which the feed motor 69 is connected via an electromagnetic clutch, receives the driving force of the feed motor 69 and starts rotating, and starts feeding the paper P stacked in the paper feed tray 30.

[0057] The control unit 101 increments the number of prints by one in order to accumulate the number of times the image forming apparatus 100 has been used and to determine the timing of maintenance (S404).

[0058] Next, the jam detection unit 109 starts measuring the jam detection time (S405). If the registration sensor 31 does not detect the paper P before the jam detection time has elapsed, it is determined that a jam has occurred. There is a relationship between the jam detection time and the registration restart time: "jam detection time>registration restart time."

[0059] Next, the control unit 101 determines whether or not the registration sensor 31 has detected the leading edge of the paper P (S406). If the determination in step S406 is Yes, the process proceeds to step S407, and if the determination is No, the process proceeds to step S412.

[0060] In step S407, since the paper P has been detected by the registration sensor 31, the image retransmission control unit 108 initializes the number of retransmissions to "0" (S407). Note that the number of retransmissions is the number of times image retransmissions have been performed consecutively.

[0061] Next, the control unit 101 resumes the rotation of the registration roller pair 32 (S408). By the time of reaching step S408, the image creation process completed by the image creation processor 102 has caused the toner image to be transferred to the intermediate transfer belt 16 by the primary transfer roller 19, and the intermediate transfer belt 16 has fed the toner image toward the secondary transfer roller 20. The control unit 101 resumes the rotation of the registration roller pair 32 at the timing when the toner image carried on the intermediate transfer belt 16 and the paper P waiting at the registration roller pair 32 are aligned at the secondary transfer roller 20.

[0062] As a result, the toner image is transferred to the paper P by the secondary transfer roller 20 (S409). Thereafter, the paper P onto which the toner image has been transferred is fed to the fixing device 34, and the fixing section 103 executes a fixing process (S410).

[0063] Thereafter, the paper P on which the toner image has been fixed by the fixing device 34 is discharged outside the image forming apparatus 100 (S411), and the printing process is completed.

[0064] In step S412, the jam detector 109 determines whether the jam detection time has elapsed (S412). If the determination in step S412 is Yes, the process proceeds to step S413, and if the determination is No, the process proceeds to step S415.

[0065] In step S413, jam detection unit 109 detects a jam of paper P (S413). Upon detection of the jam, control unit 101 suspends printing (S414). Thereafter, display unit 106 displays a message urging the user to remove the jammed paper, and after control unit 101 determines that the jammed paper has been removed, it returns to S401 and resumes the printing operation. In other words, in the case of a jam, printing resumes automatically.

[0066] In step S415, the registration monitoring unit 110 judges whether or not the registration restart time has elapsed (S415). If the judgment in step S415 is Yes, the process proceeds to step S416, and if the judgment is No, the process proceeds to step S406.

[0067] In step S416, since the registration sensor 31 does not detect the paper P even though the registration restart time has elapsed, the control unit 101 determines that a delay has occurred in the paper P. If a delay has occurred in the paper P, the image can be transferred to the paper P by image retransmission, so the control unit 101 determines whether the image retransmission function is enabled (S416).

[0068] If the determination in step S416 is Yes, the process proceeds to step S419, and if the determination is No, the process proceeds to step S417.

[0069] In step S417, the jam detection unit 109 detects a jam of the paper P (S417). In response to the detection of the jam, the control unit 101 suspends printing (S418). In other words, if the image retransmission function is disabled, the jam is deemed to have occurred, and the image forming apparatus 100 does not perform image retransmission control, thereby suppressing an increase in toner consumption and travel distance.

[0070] In step S419, the judgment unit 111 judges whether the number of retransmissions is greater than a jam judgment threshold (an example of a first threshold) (S419). That is, it is judged whether the condition "when the number of consecutive image retransmissions exceeds the jam judgment threshold" is met. As described later, the number of retransmissions is incremented by one each time step S424 is executed, and is initialized in step S407. As long as the process does not pass step S407, that is, when step S424 is executed consecutively a number of times that exceeds the jam judgment threshold (an integer of 1 or more), it is judged as Yes in step S419. The jam judgment threshold may be "0", and in this case, if a delay in the paper P occurs even once, it is possible to display a message that the image forming apparatus 100 will clean the paper feed rollers.

[0071] If the determination in step S419 is Yes, the process proceeds to step S420, and if the determination is No, the process proceeds to step S422.

[0072] In step S420, the jam detection unit 109 detects a jam of the paper P (S420). Upon detection of the jam, the control unit 101 suspends printing (S421).

[0073] In step S422, since the number of retransmissions is equal to or less than the jam determination threshold, the control unit 101 starts image retransmission control. First, the control unit 101 causes the image creation process unit 102 to stop image creation (S422).

[0074] Next, the control unit 101 determines whether or not the registration sensor 31 has detected the leading edge of the paper P (S423). If the determination in step S423 is Yes, the process proceeds to step S424, and if the determination is No, the process proceeds to step S430.

[0075] In step S425, the image retransmission control unit 108 increments the number of retransmissions for the determination in step S419 by one (S424).

[0076] Next, the control unit 101 causes the image creation processor 102 to re-form the image (S425). The image creation processor 102 creates a toner image and causes the primary transfer roller 19 to transfer it to the intermediate transfer belt 16. The control unit 101 restarts the registration roller pair 32 at a timing when the toner image carried on the intermediate transfer belt 16 by the secondary transfer roller 20 and the paper P waiting at the registration roller pair 32 are aligned (S426).

[0077] As a result, the toner image is transferred to the paper P by the secondary transfer roller 20 (S427). Thereafter, the paper P onto which the toner image has been transferred is fed to the fixing device 34, and the fixing section performs a fixing process (S428).

[0078] Thereafter, the paper P on which the toner image has been fixed by the fixing device 34 is discharged outside the image forming apparatus 100 (S429), and the printing process is completed.

[0079] In step S430, the jam detector 109 determines whether the jam detection time has elapsed (S430). If the determination in step S430 is Yes, the process proceeds to step S431, and if the determination is No, the process proceeds to step S423.

[0080] In step S431, the jam detection unit 109 detects a jam of the paper P (S431). Upon detection of the jam, the control unit 101 suspends printing (S432).

[0081] By the above process, image forming apparatus 100 performs image retransmission control in response to a delay in paper P, and when the number of retransmissions exceeds the jam determination threshold, determines that a jam has occurred, thereby suppressing an increase in toner consumption and travel distance. However, in FIG. 4, when image retransmissions are performed consecutively as in step S419, it is determined that a jam has occurred, printing is interrupted, and the user must carry out the jam removal operation.

[0082] Therefore, the image forming apparatus 100 of the present embodiment does not interrupt printing when a jam is detected, but notifies the user to clean the paper feed rollers, as described below. This makes it possible to suppress toner consumption and increases in travel distance, and also to suppress the user from having to perform jam removal work.

[0083] <Notify to clean the paper feed rollers if image resending occurs continuously> Fig. 5 is a flowchart showing the flow of image forming processing executed in image forming apparatus 100 according to this embodiment. Note that the explanation of Fig. 5 may mainly focus on the differences from Fig. 4. Steps S501 and S502 have been added in Fig. 5, so these steps will be explained in detail.

[0084] In Fig. 4, if it is determined in step S419 that the number of resends is greater than the jam determination threshold, a jam is detected even if a jam does not actually occur. Since the user cannot determine whether a jam has occurred or an image resend has occurred, the user ends up performing a jam removal operation. Therefore, the image forming apparatus 100 of this embodiment displays a message to clean the paper feed roller as follows.

[0085] If it is determined in step S419 that the number of resends is greater than the jam determination threshold, in step S501, the control unit 101 stops the next printing (S501). Then, the display unit 106 displays a message to clean the paper feed rollers (S502). Examples of a message to clean the paper feed rollers are shown in Figs. 6 and 7. The next printing refers to printing of the next page and onwards. Printing is stopped even if one print job is still in progress.

[0086] After printing has stopped, printing of the next page and subsequent pages will not resume unless the user performs an operation to resume printing. Since printing is temporarily stopped, the user can clean the paper feed rollers after image retransmission control has ended and the paper has been discharged. After step S502, image retransmission control is performed, but since the next printing is stopped, the user can clean the paper feed rollers to prevent the paper P from slipping and improve printing efficiency. In other words, when an image forming device prints a large volume, stopping printing once to perform cleaning is more efficient, and doing so can shorten the time until printing is completed. In addition, the user does not need to perform the work of removing a jam even if a jam has not occurred.

[0087] As will be described with reference to FIG. 7, it is preferable that the user be able to select whether to stop the next print job or to forcibly print the job.

[0088] <Example of notification to users> 6 shows a notification screen 200 for the user displayed on the display unit 106. This notification screen 200 displays a message 201 saying, "Productivity is decreasing due to delayed paper feed. Please clean the paper feed rollers." The user cleans the paper feed rollers upon seeing the message 201, so that it is possible to suppress increases in toner consumption and travel distance, and thus suppress a decrease in productivity.

[0089] 6, if message 201 is simply displayed, the next printing is stopped in step S501. Since image forming apparatus 100 has stopped, the user can easily clean the paper feed rollers, and cleaning can improve production efficiency. However, there are cases where the user wants to continue printing and finish the print job because there is only a little left in the print job, or there are cases where the user knows that the conditions for displaying message 201 are strict and wants to continue printing even if image resending occurs.

[0090] Therefore, it is preferable that the user be able to select whether to stop printing or to forcibly print, as shown in Fig. 7. Fig. 7 shows a notification screen 210 for the user who can forcibly print. The notification screen 210 is displayed in S502, skipping step S501. The notification screen 210 displays a message 211 saying "Productivity is decreasing due to delayed paper feed. Please clean the paper feed rollers", a print cancel button 212, and a forced print button 213. The user sees the message 211 and cleans the paper feed rollers.

[0091] The user can cancel the next print job by pressing the print cancel button 212, or can force print by pressing the force print button 213. Regardless of whether the print cancel button 212 or the force print button 213 is pressed, the control unit 101 executes step S422 and subsequent steps in Fig. 5. However, when the print cancel button 212 is pressed, printing of the next page and subsequent pages is not performed, and the print job is canceled when the toner image currently being created is printed under image resend control.

[0092] <Conditions for notifying the user to clean the paper feed roller> 5, when it is determined in step S419 that the number of consecutive image retransmissions is greater than the jam determination threshold, the display unit 106 displays a message to clean the feed rollers. On the other hand, the condition for the display unit 106 to display a message to clean the feed rollers may be as follows. When the occurrence rate of image resends within the same job exceeds the occurrence rate judgment threshold (an example of the second threshold). - When the total downtime caused by image resending within the same job exceeds the downtime judgment threshold (an example of the third threshold).

[0093] 8 is a flow chart for explaining a process in which the display unit 106 displays a message to clean the feed rollers when the occurrence rate of image retransmissions in the same job exceeds the occurrence rate determination threshold value. Note that FIG. 8 is an excerpt of steps S419 to S502 in FIG. 5.

[0094] In step S419-2, the judgment unit 111 judges whether the occurrence rate of image retransmissions within the same job exceeds the occurrence rate judgment threshold (S419-2). The same job is one print command to print a set number of pages and copies of one file to be printed. The image retransmission control unit 108 counts the number of times A that image retransmissions occurred and the number of times B that image retransmissions did not occur within the same job, and calculates the occurrence rate. Note that the number of times A that image retransmissions occurred may be the number of times step S425 was executed, and the number of times that image retransmissions did not occur may be the number of times step S407 was executed. Incidence rate = A / (A+B)

[0095] The determination unit 111 compares the occurrence rate with the occurrence rate determination threshold value. If the determination in step S419-2 is Yes, steps S501 and S502 are executed.

[0096] According to such a condition, even if the number of consecutive image retransmissions does not exceed the jam determination threshold, if the occurrence rate within the same job is high, the display unit 106 can display a message to clean the paper feed rollers.

[0097] Instead of the occurrence rate, the display unit 106 may display a message to clean the feed roller when the number of occurrences of image retransmissions within the same job exceeds an occurrence count threshold. Also, the occurrence rate may be an occurrence rate within a certain period of time in the past, rather than within the same job.

[0098] 9 is a flow chart for explaining a process in which the display unit 106 displays a message to clean the feed rollers when the total downtime caused by image retransmissions in the same job exceeds the downtime determination threshold. Note that FIG. 9 shows steps S419 to S502 extracted from FIG. 5.

[0099] In step S419-3, the judgment unit 111 judges whether the total downtime caused by image retransmission within the same job exceeds a downtime judgment threshold (S419-3). Downtime is the extra time caused by a delay in the paper P, which is longer than the time required for one print job when the paper P is not delayed. Specifically, it is the time from when the registration restart time has elapsed until the pair of registration rollers 32 restarts in step S426. The total within the same job is the total of these downtimes. Note that this is different from the downtime during which the user is unable to use the image forming apparatus 100. The image retransmission control unit 108 measures the downtime and calculates the total downtime within the same job.

[0100] The determination unit 111 compares the total downtime with the downtime determination threshold value. If the determination in step S419-3 is Yes, steps S501 and S502 are executed.

[0101] According to such conditions, even if the number of consecutive image resends does not exceed the jam determination threshold, when the downtime becomes long, the display unit 106 can display a message to clean the feed rollers. In other words, since the user can know the decrease in printing efficiency in units of time, it is easy to urge the user to clean the feed rollers.

[0102] The total downtime is not limited to downtime within the same job, and may be the total downtime within a certain period of time in the past. If even one downtime is extremely long, step S419-3 may be judged as YES even if the total does not exceed the downtime judgment threshold. If even one downtime is extremely long, step S419-3 will always be judged as YES, so image forming apparatus 100 can promptly display a message indicating that the paper feed rollers should be cleaned.

[0103] <<Selecting the condition to notify the user to clean the paper feed roller>> If the user can set the conditions of steps S419, S419-2, and S419-3 in the image forming apparatus, the user can set the conditions for cleaning the paper feed rollers by himself.

[0104] 10 shows a notification condition setting screen 220 displayed on the display unit 106. The notification condition setting screen 220 may be displayed by a terminal device or the like operated by a user communicating with the image forming apparatus 100. The notification condition setting screen 220 may be displayed by a terminal device or the like operated by a user communicating with the image forming apparatus 100. - When the number of consecutive image retransmissions exceeds the jam detection threshold 221 - When the occurrence rate of image retransmissions in the same job exceeds the occurrence rate judgment threshold 222 - When the total downtime caused by image retransmission in the same job exceeds the downtime judgment threshold 223 Check boxes 224 to 226 are displayed in association with each of the above. Note that the jam determination threshold, the occurrence rate determination threshold, and the downtime determination threshold can be set by the user.

[0105] By checking one or more of the check boxes 224 to 226, the user can set the conditions for notifying the user to clean the paper feed rollers.

[0106] <Major Effects> The image forming apparatus of this embodiment detects the occurrence of a paper delay (slippage), and if a certain condition is met, it stops printing once and notifies the user, for example by a pop-up, that the paper feed rollers should be cleaned. This eliminates the need for the user to remove the jam. It also reduces the disadvantages of increased toner consumption and mileage. In addition, since the user can know that the image resend function has been activated, the image forming apparatus can urge the user to clean the paper feed rollers. Furthermore, by temporarily stopping printing, when the image forming apparatus is printing a large volume, it is possible to urge the user to stop printing and perform cleaning, thereby shortening the time until printing is completed.

[0107] <Other application examples> The above describes the best mode for carrying out this embodiment using examples, but this embodiment is not limited to these examples in any way, and various modifications and substitutions can be made within the scope that does not deviate from the gist of this embodiment.

[0108] For example, in this embodiment, image retransmission performed by an electrophotographic image forming apparatus 100 has been described, but the printing method is not important as long as the image forming apparatus 100 feeds paper P using a paper feed roller, such as an inkjet image forming apparatus 100.

[0109] In addition, when the number of consecutive image retransmissions exceeds the jam determination threshold and a size mismatch occurs between the paper size set by the user and the size of the paper actually set in the tray, the display unit 106 may notify the user that the paper feed roller should be cleaned.

[0110] In the present embodiment, the image forming apparatus 100 displays the message that the feed roller should be cleaned, but a terminal device that communicates with the image forming apparatus 100 via a network may display the message that the feed roller should be cleaned. For example, if the terminal device is running a printer driver, the printer driver displays the message that the feed roller should be cleaned. If the terminal device communicates with the image forming apparatus 100 using a Web browser, the message that the feed roller should be cleaned may be displayed by receiving a Web page. Alternatively, the terminal device may connect to a management server that communicates with the image forming apparatus 100 and display the message that the feed roller should be cleaned by receiving a Web page.

[0111] In addition, in this embodiment, an intermediate transfer belt type image forming apparatus 100 has been described, but a direct transfer type image forming apparatus 100 in which a toner image is transferred directly from the process unit 1 to the paper P may also display a message indicating that the feed roller should be cleaned.

[0112] In addition, the configuration example in Fig. 3 and the like is divided according to main functions in order to facilitate understanding of the processing by the image forming apparatus 100. The present invention is not limited by the manner in which the processing units are divided or the names of the processing units. The processing by the image forming apparatus 100 can be further divided into more processing units depending on the processing contents. Also, it can be divided so that one processing unit includes even more processes.

[0113] Each function of the above-described embodiments can be realized by one or more processing circuits. Here, the term "processing circuit" in this specification includes a processor programmed to execute each function by software, such as a processor implemented by an electronic circuit, and a device such as an ASIC (Application Specific Integrated Circuit), a DSP (digital signal processor), an FPGA (field programmable gate array), or a conventional circuit module designed to execute each function described above.

[0114] <Additional Notes> [Claim 1] An image forming apparatus that transfers an image formed on an image carrier to a recording medium by a transfer unit, a feeding section that feeds the recording medium from a storage section in which the recording medium is stored to the transfer section; a display unit that displays a message indicating that the feed roller should be cleaned when a feeding time from a start of feeding to a time when the recording medium is detected at the transfer unit exceeds a threshold value; An image forming apparatus comprising: [Claim 2] 2. The image forming apparatus according to claim 1, further comprising a control unit that stops the next printing when the feeding time exceeds a threshold value. [Claim 3] the display unit displays a soft key for accepting whether to continue the next printing or to cancel the next printing together with a message to the effect that the feeding roller should be cleaned; an operation unit that accepts depression of the soft key; the control unit continues the next printing if the feeding time exceeds a threshold value when the operation unit accepts pressing of the soft key for continuing the next printing, 3. The image forming apparatus according to claim 2, wherein when the operation unit accepts pressing of the soft key for canceling the next printing, if the feeding time exceeds a threshold value, the next printing is canceled. [Claim 4] an image retransmission control unit that, when the feeding time exceeds a threshold value, forms an image on the image carrier again, and when the recording medium is detected in the transfer unit, performs image retransmission by transferring the image formed on the image carrier to the recording medium in the transfer unit; 4. The image forming apparatus according to claim 1, wherein the display unit displays a message to the effect that the feed roller should be cleaned when the number of image retransmissions exceeds a first threshold value. [Claim 5] an image retransmission control unit that, when the feeding time exceeds a threshold value, forms an image on the image carrier again, and when the recording medium is detected in the transfer unit, performs image retransmission by transferring the image formed on the image carrier to the recording medium in the transfer unit; 4. The image forming apparatus according to claim 1, wherein the display unit displays a message indicating that the feed roller should be cleaned when the occurrence rate of the image retransmission within the same job exceeds a second threshold value. [Claim 6] an image retransmission control unit that, when the feeding time exceeds a threshold value, forms an image on the image carrier again, and when the recording medium is detected in the transfer unit, performs image retransmission by transferring the image formed on the image carrier to the recording medium in the transfer unit; 4. The image forming apparatus according to claim 1, wherein the display unit displays a message to the effect that the feed roller should be cleaned when a total amount of downtime caused by the image retransmission within the same job exceeds a third threshold. [Claim 7] The conditions for displaying the need to clean the feed roller are as follows: When the image retransmission is performed continuously more than a first threshold value, When the occurrence rate of image retransmissions in the same job exceeds a second threshold value, and If the total downtime caused by image retransmission in the same job exceeds a third threshold, 7. The image forming apparatus according to claim 4, wherein the conditions are received from a user. [Claim 8] The image retransmission can be set to be enabled or disabled, When the image retransmission is enabled, if the feeding time exceeds a threshold value, the display unit displays a message indicating that the feeding roller should be cleaned; 8. The image forming apparatus according to claim 4, wherein, when the image retransmission is disabled and the feeding time exceeds a threshold value, the display unit displays a message that a paper jam has been detected. [Claim 9] When the feeding time exceeds the threshold value and the paper size set by the user differs from the size of the paper actually set in the tray, 2. The image forming apparatus according to claim 1, wherein the display unit displays a message that the feed roller should be cleaned. [Explanation of symbols]

[0115] 16 Intermediate transfer belt 31 Resist sensor 32 Registration roller pair 47 Paper feed roller 100 Image forming device [Prior art documents] [Patent documents]

[0116] [Patent Document 1] JP 2008-052257 A

Claims

1. An image forming apparatus that transfers an image formed on an image carrier to a recording medium by a transfer unit, a feeding section that feeds the recording medium from a storage section in which the recording medium is stored to the transfer section; a display unit that displays a message to the effect that the feed roller should be cleaned when a feeding time from a start of feeding until the recording medium is detected at the transfer unit exceeds a threshold value; An image forming apparatus comprising:

2. The image forming apparatus according to claim 1 , further comprising a control unit that stops the next printing when the feeding time exceeds a threshold value.

3. the display unit displays a soft key for accepting an instruction to continue the next printing or to cancel the next printing together with a message to the effect that the feeding roller should be cleaned, an operation unit that accepts depression of the soft key; the control unit continues the next printing if the feeding time exceeds a threshold value when the operation unit accepts pressing of the soft key for continuing the next printing, The image forming apparatus according to claim 2 , wherein when the operation unit accepts pressing of the soft key for canceling the next printing, if the feeding time exceeds a threshold value, the next printing is canceled.

4. an image retransmission control unit that, when the feeding time exceeds a threshold value, forms an image on the image carrier again, and when the recording medium is detected in the transfer unit, performs image retransmission by transferring the image formed on the image carrier to the recording medium in the transfer unit; 4. The image forming apparatus according to claim 1, wherein the display unit displays a message to the effect that the feed roller should be cleaned when the number of image retransmissions exceeds a first threshold value.

5. an image retransmission control unit that, when the feeding time exceeds a threshold value, forms an image on the image carrier again, and when the recording medium is detected in the transfer unit, performs image retransmission by transferring the image formed on the image carrier to the recording medium in the transfer unit; The image forming apparatus according to any one of claims 1 to 3, wherein the display unit displays a message indicating that the feed roller should be cleaned when the occurrence rate of image retransmission within the same job exceeds a second threshold value.

6. an image retransmission control unit that, when the feeding time exceeds a threshold value, forms an image on the image carrier again, and when the recording medium is detected in the transfer unit, performs image retransmission by transferring the image formed on the image carrier to the recording medium in the transfer unit; The image forming apparatus according to any one of claims 1 to 3, wherein the display unit displays a message indicating that the feed roller should be cleaned when the total downtime caused by the image retransmission within the same job exceeds a third threshold.

7. The conditions for displaying the need to clean the feed roller are as follows: When the image retransmission is performed continuously more than a first threshold value, When the occurrence rate of image retransmissions in the same job exceeds a second threshold value, and If the total downtime caused by image retransmission in the same job exceeds a third threshold, The image forming apparatus according to claim 4 , wherein the conditions are received from a user.

8. The image retransmission can be set to be enabled or disabled, When the image retransmission is enabled, if the feeding time exceeds a threshold value, the display unit displays a message indicating that the feeding roller should be cleaned; 5. The image forming apparatus according to claim 4, wherein if the image retransmission is disabled and the feeding time exceeds the threshold value, the display unit displays a message indicating that a paper jam has been detected.

9. When the feeding time exceeds the threshold value and the paper size set by the user differs from the size of the paper actually set in the tray, 2. The image forming apparatus according to claim 1, wherein the display unit displays a message that the feed roller should be cleaned.

10. A display method performed by an image forming apparatus that transfers an image formed on an image carrier to a recording medium at a transfer unit, comprising: A process of feeding the recording medium from a storage unit in which the recording medium is stored to the transfer unit; a process of displaying a message indicating that the feed roller should be cleaned when a feed time from the start of feeding to the detection of the recording medium at the transfer unit exceeds a threshold value; How to display.

11. An image forming apparatus that transfers an image formed on an image carrier to a recording medium at a transfer unit, A process of feeding the recording medium from a storage unit in which the recording medium is stored to the transfer unit; a process of displaying a message indicating that the feed roller should be cleaned when a feeding time from the start of feeding to the detection of the recording medium at the transfer unit exceeds a threshold value; A program that executes the following.

Images