Image forming apparatus and prohibition control method

Abstract

The present invention provides an image forming apparatus and a control method that can suppress deformation of continuous paper. [Solution] The image forming apparatus comprises an image forming unit that forms an image on continuous paper, a fixing unit that fixes the image formed by the image forming unit to the continuous paper, a transport unit that transports the continuous paper from the image forming unit toward the fixing unit, an adjustment control unit that performs an adjustment process by the image forming unit and, if the adjustment process is performed, controls the transport unit to return and transport the continuous paper, and a prohibition control unit that controls whether or not to prohibit the execution of the adjustment process according to the continuous paper information.

Description

Technical Field

[0001] The present invention relates to an image forming apparatus and a prohibition control method.

Background Art

[0002] In an image forming apparatus, during continuous printing, the color tone of an image may change due to environmental changes such as temperature and humidity, and toner state. Therefore, in an image forming apparatus, after a job starts, when a certain period of time has elapsed or when formation of a predetermined number of images is completed, adjustment processing for maintaining image quality is generally performed. When the adjustment processing is performed, the printing process is interrupted, and after the adjustment processing is completed, the printing process is restarted.

[0003] However, in an image forming apparatus that forms an image on continuous paper such as roll paper, when the printing process is restarted after completion of the adjustment processing, the printing process is restarted in a state where a blank portion where no image is formed on the continuous paper has been conveyed a certain distance. Therefore, if the printing process is restarted as it is, a problem of increased cost due to the occurrence of blank portions occurs. Also, when there is a post-processing device, a problem that post-processing cannot be performed due to the presence of blank portions also occurs.

[0004] Therefore, a configuration is known in which the continuous paper is conveyed back and an image is formed on the blank portion so that no blank portion occurs (see, for example, Patent Document 1). In this technique, in order to suppress a change in the color tone of a printed matter that occurs due to the continuous paper being conveyed through the fixing portion a plurality of times by conveying it back, parameters are switched with the fixing temperature and the conveyance speed.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] Incidentally, in recent years, various types of media have come into circulation, and among them are media made of materials that make it impossible to transport the fixing section multiple times. When such media are used as continuous paper, if the continuous paper is transported back based on the adjustment process described above, a problem arises in which the continuous paper deforms.

[0007] The object of the present invention is to provide an image forming apparatus and a prohibition control method capable of suppressing deformation of continuous paper. [Means for solving the problem]

[0008] The image forming apparatus according to the present invention is An image forming unit that forms an image on continuous paper, A fixing unit for fixing the image formed by the image forming unit onto the continuous paper, A transport unit that transports the continuous paper from the image forming unit toward the fixing unit, An adjustment control unit that performs the adjustment process by the image forming unit and, when the adjustment process is performed, controls the transport unit to return and transport the continuous paper, A prohibition control unit that controls whether or not to prohibit the execution of the adjustment process according to the continuous paper information, It is equipped with.

[0009] The prohibition control method according to the present invention is A method for controlling the prohibition of an image forming apparatus, comprising an image forming unit for forming an image on continuous paper, and a fixing unit for fixing the image formed by the image forming unit onto the continuous paper, The continuous paper is transported from the image forming unit toward the fixing unit, The adjustment process is performed by the image forming unit, and when the adjustment process is performed, the continuous paper is controlled to be returned and transported. It has, The system further includes controlling whether or not to prohibit the execution of the adjustment process in accordance with the continuous paper information between transporting the continuous paper and returning it. [Effects of the Invention]

[0010] According to the present invention, deformation of continuous paper can be suppressed. [Brief explanation of the drawing]

[0011] [Figure 1] This figure schematically shows the overall configuration of an image forming system equipped with an image forming apparatus according to an embodiment of the present invention. [Figure 2] This figure shows the main components of the control system of the image forming apparatus according to this embodiment. [Figure 3] This is a diagram illustrating how an image is formed on continuous paper. [Figure 4] This diagram illustrates how blank spaces appear on continuous paper due to the adjustment process. [Figure 5] This is a diagram illustrating the process of return transport. [Figure 6] This flowchart shows an example of the operation of image formation control in an image forming apparatus. [Figure 7] This figure shows the main components of the control system of an image forming apparatus according to a modified example. [Figure 8] This figure shows the main components of the control system of an image forming apparatus according to a modified example. [Figure 9] This flowchart shows an example of the operation of image formation control in an image forming apparatus according to a modified example. [Modes for carrying out the invention]

[0012] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Figure 1 is a schematic diagram showing the overall configuration of an image forming system 100 equipped with an image forming apparatus 1 according to an embodiment of the present invention. Figure 2 is a diagram showing the main part of the control system of the image forming apparatus 1 according to this embodiment.

[0013] The image forming system 100 is a system that forms an image on a recording medium (including a recording medium such as continuous paper P shown by a thick line in FIG. 1). Here, the continuous paper P is a continuous medium having a length exceeding the main body width of the image forming apparatus 1, for example, in its conveyance direction, and is, for example, roll paper.

[0014] As shown in FIG. 1, the image forming system 100 includes a paper feeding device 2, an image forming device 1, and a winding device 3, which are connected in order from the upstream side along the conveyance direction of the continuous paper P.

[0015] The paper feeding device 2 is a device that feeds the continuous paper P to the image forming device 1. Inside the housing of the paper feeding device 2, the continuous paper P is held in a state of being wound around a support shaft in a roll shape. The paper feeding device 2 feeds the continuous paper P wound around the support shaft to the image forming device 1 at a constant speed via a plurality of conveyance roller pairs such as a feeding roller and a paper feeding roller. The paper feeding operation of the paper feeding device 2 is controlled by the control unit 101 provided in the image forming device 1.

[0016] The image forming device 1 is an intermediate transfer type color image forming device that uses electrophotographic process technology. That is, the image forming device 1 primarily transfers the Y (yellow), M (magenta), C (cyan), and K (black) toner images formed on the photosensitive drum 413 to the intermediate transfer belt 421, overlaps the four-color toner images on the intermediate transfer belt 421, and then secondarily transfers them to the continuous paper P fed from the paper feeding device 2 to form an image.

[0017] In addition, the image forming device 1 employs a tandem method in which the photosensitive drums 413 corresponding to the four colors of YMCK are arranged in series in the running direction of the intermediate transfer belt 421, and the respective color toner images are sequentially transferred to the intermediate transfer belt 421 in one procedure.

[0018] As shown in FIG. 2, the image forming device 1 includes an image reading unit 10, an operation display unit 20, an image processing unit 3, an image forming unit 40, a paper conveyance unit 50, a fixing unit 60, and a control unit 101.

[0019] The control unit 101 includes a CPU (Central Processing Unit) 102, a ROM (Read Only Memory) 103, a RAM (Random Access Memory) 104, etc. The CPU 102 reads a program corresponding to the processing content from the ROM 103, loads it into the RAM 104, and works in cooperation with the loaded program to centrally control the operation of each block of the image forming apparatus 1. At this time, various data stored in the storage unit 72 are referenced. The storage unit 72 is composed of, for example, a non-volatile semiconductor memory (so-called flash memory) or a hard disk drive.

[0020] The control unit 101 transmits and receives various types of data to and from external devices (e.g., personal computers) connected to a communication network such as a LAN (Local Area Network) or WAN (Wide Area Network) via the communication unit 71. For example, the control unit 101 receives image data transmitted from an external device and forms an image on continuous paper P based on this image data (input image data). The communication unit 71 is composed of a communication control card, such as a LAN card.

[0021] As shown in Figure 1, the image reading unit 10 is configured to include an automatic document feeder 11 called an ADF (Auto Document Feeder) and a document image scanning device 12 (scanner), etc.

[0022] The automatic document feeder 11 transports the documents D placed in the document tray using a transport mechanism and sends them to the document image scanner 12. The automatic document feeder 11 makes it possible to continuously scan images (including both sides) of multiple documents D placed in the document tray all at once.

[0023] The document image scanning device 12 optically scans a document transported from the automatic document feeder 11 onto the contact glass or a document placed on the contact glass, and images the reflected light from the document onto the light-receiving surface of the CCD (Charge Coupled Device) sensor 12a to read the document image. The image reading unit 10 generates input image data based on the reading result by the document image scanning device 12. This input image data is subjected to predetermined image processing by the image processing unit 30.

[0024] As shown in Figure 2, the operation display unit 20 is composed of, for example, a liquid crystal display (LCD) with a touch panel, and functions as a display unit 21 and an operation unit 22. The display unit 21 displays various operation screens, image status, and the operating status of each function in accordance with the display control signals input from the control unit 101. The operation unit 22 is equipped with various operation keys such as a numeric keypad and a start key, and accepts various input operations from the user and outputs operation signals to the control unit 101.

[0025] The image processing unit 30 includes circuits and other components that perform digital image processing on the input image data according to initial settings or user settings. For example, under the control of the control unit 101, the image processing unit 30 performs gradation correction based on gradation correction data (gradation correction table). In addition to gradation correction, the image processing unit 30 also performs various correction processes such as color correction and shading correction, as well as compression processing, on the input image data. The image forming unit 40 is controlled based on the image data that has undergone these processes.

[0026] As shown in Figure 1, the image forming unit 40 includes image forming units 41Y, 41M, 41C, 41K, an intermediate transfer unit 42, etc., for forming images using colored toners of Y, M, C, and K components based on input image data.

[0027] The image forming units 41Y, 41M, 41C, and 41K for the Y, M, C, and K components have similar configurations. For the sake of illustration and explanation, common components are indicated by the same reference numeral, and when distinguishing between them, Y, M, C, or K is added to the reference numeral. In Figure 1, only the components of the image forming unit 41Y for the Y component are labeled with reference numerals, while the components of the other image forming units 41M, 41C, and 41K are omitted.

[0028] The image forming unit 41 includes an exposure device 411, a developing device 412, a photoreceptor drum 413, a charging device 414, and a drum cleaning device 415, etc.

[0029] The photoconductor drum 413 is a negatively charged organic photoconductor (OPC) in which an undercoat layer (UCL), a charge generation layer (CGL), and a charge transport layer (CTL) are sequentially laminated on the circumferential surface of a conductive cylindrical body (aluminum tube), for example, made of aluminum.

[0030] The control unit 101 rotates the photoreceptor drum 413 at a constant peripheral speed by controlling the drive current supplied to the drive motor (not shown) that rotates the photoreceptor drum 413.

[0031] The charging device 414 has a charging grid (not shown) and is a band electrode that uniformly charges the surface of the photoconductive photoreceptor drum 413 with negative polarity. The exposure device 411 is composed of, for example, a semiconductor laser and irradiates the photoreceptor drum 413 with laser light corresponding to the image of each color component.

[0032] The developing device 412 is a two-component developing device that forms a toner image by visualizing an electrostatic latent image by depositing toner of each color component onto the surface of the photoreceptor drum 413.

[0033] The drum cleaning device 415 has drum cleaning blades and the like that are slid into contact with the surface of the photoreceptor drum 413, and removes any remaining toner after primary transfer from the surface of the photoreceptor drum 413.

[0034] The intermediate transfer unit 42 includes an intermediate transfer belt 421, a primary transfer roller 422, a plurality of support rollers 423, a secondary transfer roller 424, and a belt cleaning device 426, etc.

[0035] The intermediate transfer belt 421 is an endless belt and is stretched in a loop around a plurality of support rollers 423. At least one of the plurality of support rollers 423 is a drive roller, and the others are driven rollers. For example, it is preferable that the roller 423A, which is located downstream in the belt travel direction from the primary transfer roller 422 for component K, is the drive roller. This makes it easier to maintain a constant belt travel speed in the primary transfer section. As the drive roller 423A rotates, the intermediate transfer belt 421 travels at a constant speed in the direction of arrow A.

[0036] The intermediate transfer belt 421 is a conductive and elastic belt, and is rotationally driven by a control signal from the control unit 101.

[0037] The primary transfer roller 422 is positioned on the inner circumferential side of the intermediate transfer belt 421, facing the photoreceptor drum 413 for each color component. By pressing the primary transfer roller 422 against the photoreceptor drum 413 with the intermediate transfer belt 421 in between, a primary transfer nip is formed for transferring the toner image from the photoreceptor drum 413 to the intermediate transfer belt 421.

[0038] The secondary transfer roller 424 is positioned on the outer circumferential surface side of the intermediate transfer belt 421, opposite the backup roller 423B which is located downstream of the drive roller 423A in the belt travel direction. By pressing the secondary transfer roller 424 against the backup roller 423B with the intermediate transfer belt 421 in between, a secondary transfer nip is formed for transferring the toner image from the intermediate transfer belt 421 to the continuous paper P.

[0039] As the intermediate transfer belt 421 passes over the primary transfer nip, the toner image on the photoreceptor drum 413 is sequentially transferred onto the intermediate transfer belt 421 as a primary transfer. Subsequently, as the continuous paper P passes over the secondary transfer nip, the toner image on the intermediate transfer belt 421 is transferred to the continuous paper P as a secondary transfer. The continuous paper P, on which the toner image has been transferred, is then transported toward the fuser unit 60.

[0040] The belt cleaning device 426 removes any remaining transfer toner from the surface of the intermediate transfer belt 421 after secondary transfer.

[0041] The fixing unit 60 includes an upper fixing unit 60A having a fixing surface side member positioned on the fixing surface side of the continuous paper P, i.e., the side on which the toner image is formed, and a lower fixing unit 60B having a back side support member positioned on the back side of the continuous paper P, i.e., the side opposite to the fixing surface. When the back side support member is pressed against the fixing surface side member, a fixing nip is formed that grips and transports the continuous paper P.

[0042] The fuser unit 60 heats and pressurizes the continuous paper P, which has been transported after the toner image has been secondarily transferred, using a fuser nip, thereby fixing the toner image to the continuous paper P. The fuser unit 60 is arranged as a unit within the fuser unit F.

[0043] The paper transport unit 50 includes a paper discharge unit 52 and a transport path unit 53, etc. The transport path unit 53 has a plurality of transport roller pairs, including a registration roller pair 53a.

[0044] The continuous paper P fed from the paper feeder 2 to the image forming apparatus 1 is transported to the image forming unit 40 by the transport path 53. In the image forming unit 40, the toner image from the intermediate transfer belt 421 is transferred to one side of the continuous paper P in a single secondary transfer, and a fixing process is performed in the fixing unit 60.

[0045] The continuous paper P with the image formed on it is transported to the winding device 3 by a paper discharge section 52 equipped with a transport roller pair (paper discharge roller pair) 52a.

[0046] The winding device 3 is a device that winds up the continuous paper P that has been transported from the image forming apparatus 1. Inside the housing of the winding device 3, for example, the continuous paper P is wound around a winding shaft and held in a roll shape. To this end, the winding device 3 winds the continuous paper P that has been transported from the image forming apparatus 1 onto the winding shaft at a constant speed, passing through multiple transport roller pairs (for example, a feed roller and a paper discharge roller). The winding operation of the winding device 3 is controlled by the control unit 101 of the image forming apparatus 1.

[0047] Furthermore, the image forming apparatus 1 performs adjustment processing to account for changes in the color of the image as the printing process continues during a print job. The adjustment processing consists of at least one of an image stabilization process to stabilize the image and a color shift correction process to correct color shifts in the image. The image stabilization process and the color shift correction process may be, for example, known techniques.

[0048] The adjustment process is performed when the conditions for image adjustment are met. These conditions include, for example, the completion of image formation for a predetermined number of images (e.g., 1000 images) in the image forming apparatus 1, the start of a print job, or the elapsed time since the power of the image forming apparatus 1 was turned on.

[0049] If the conditions for image adjustment are met during a print job, the printing process is interrupted and the adjustment process is performed. After the adjustment process is completed, the image forming apparatus 1 resumes the printing process. In the image forming apparatus 1 that forms an image on continuous paper P, if the conditions for image adjustment are met during a print job, the portion of the continuous paper P located in the image forming section 40 is fixed in the fixing section 60, and then the adjustment process is performed.

[0050] For example, as shown in Figure 3, in a print job, multiple images G are formed on continuous paper P. At the moment when image G1 is fixed to the continuous paper P by the fixing unit 60, the conditions for image adjustment are met, and the control unit 101 receives a request to execute the adjustment process.

[0051] At this point, since images G2 and G3 have already been formed on the continuous paper P by the image forming unit 40, it is necessary to fix images G2 and G3 to the continuous paper P before the adjustment process is performed. Therefore, images G2 and G3 are transported to the fixing unit 60 and fixed to the continuous paper P by normal transport during image formation (normal transport). After that, the adjustment process is performed in the image forming apparatus 1.

[0052] However, since the continuous paper P is continuous from the paper feeder 2 to the winding device 3, when the printing process resumes after the adjustment process is completed, the printing process will resume with a certain amount of the blank area of ​​the continuous paper P where no image has been formed having been transported.

[0053] For example, as shown in Figure 4, the adjustment process is performed when image G3 is at the position corresponding to the fixing unit 60, so the portion of the continuous paper P corresponding to the area between the fixing unit 60 and the image forming unit 40 becomes a blank area. Therefore, if the printing process is resumed in that state, image formation will resume on the continuous paper P with the blank area remaining as is. In other words, the image G4 following image G3 is formed by the image forming unit 40 with the blank area still present.

[0054] This results in wasted space and increased costs. Furthermore, if post-processing equipment is present, the presence of blank spaces can prevent post-processing of the continuous paper P.

[0055] Therefore, in this embodiment, the continuous paper P is transported in the reverse direction to form an image in the blank area. In other words, the control unit 101 executes the adjustment process by the image forming unit 40 when the conditions for image adjustment are met. Reverse transport is transport in the opposite direction to the transport performed by normal image formation. After the adjustment process is performed, the control unit 101 controls the paper transport unit 50 to transport the continuous paper P in the reverse direction. Specifically, the control unit 101 transports the continuous paper P in the reverse direction by controlling the paper transport unit 50, as well as the paper feeder 2 and the winding device 3. The control unit 101 corresponds to the "adjustment control unit" of the present invention.

[0056] For example, as shown in Figure 5, by performing a return transport from the state shown in Figure 4, it becomes possible to form image G4 in the portion adjacent to image G3 of continuous paper P.

[0057] By doing so, it becomes possible to form an image in the blank areas of the continuous paper P, thereby suppressing the occurrence of the above-mentioned problem.

[0058] Incidentally, when the continuous paper P is returned and transported, there are parts of the continuous paper P where the fixing unit 60 is transported multiple times. Specifically, when the continuous paper P is returned and transported from the state in Figure 4 to the state in Figure 5, and then normal transport is performed, at least images G2 and G3 will pass over the fixing unit 60 multiple times.

[0059] When the medium to which the continuous paper P is applied is a film material, if the area that becomes hot, such as the fixing section 60, is transported multiple times, the transported portion becomes softer and expands and contracts with even slight tension. In other words, a problem occurs in which the continuous paper P deforms.

[0060] In this embodiment, when the control unit 101 receives a request to perform an adjustment process in the middle of a print job, it controls whether or not to prohibit the execution of the adjustment process according to the information of the continuous paper P (continuous paper information). The control unit 101 corresponds to the "prohibition control unit" of the present invention.

[0061] In this case, for example, in the state shown in Figure 3, no adjustment process is performed, and images G3 and subsequent images are formed on the continuous paper P based on normal transport.

[0062] A request to perform adjustment processing in the middle of a print job occurs when the conditions for image adjustment are met during the print job.

[0063] Continuous paper information includes, for example, information about the type of continuous paper P. Examples of continuous paper P include plain paper, coated paper, film paper, etc.

[0064] For example, the control unit 101 prohibits the execution of the adjustment process if the type of continuous paper P is a film material (film paper).

[0065] In the case of film paper, it is prone to deformation if it passes through the fixing section 60 multiple times, so it is preferable not to return it to the transport section. Therefore, in this embodiment, if the type of continuous paper P is film paper, the adjustment process is prohibited. As a result, deformation of the continuous paper P can be suppressed.

[0066] Furthermore, depending on the material coated on its surface, coated paper can be easily deformed by the heat from the fixing unit 60. Therefore, the control unit 101 prohibits the execution of the adjustment process if the type of continuous paper P is coated paper and made of a material that is easily deformed by heat. This prevents the continuous paper P from deforming.

[0067] Furthermore, the control unit 101 does not prohibit the execution of the adjustment process if the type of continuous paper P is coated paper and made of a material that is resistant to thermal deformation. As a result, the adjustment process is executed.

[0068] Furthermore, when plain paper is relatively thin, it is prone to deformation due to the heat from the fixing unit 60. Therefore, the control unit 101 prohibits the execution of the adjustment process if the type of continuous paper P is plain paper and is thinner than a predetermined thickness. This suppresses deformation of the continuous paper P.

[0069] Furthermore, the control unit 101 does not prohibit the execution of the adjustment process if the type of continuous paper P is plain paper and has a thickness equal to or greater than a predetermined thickness. As a result, the adjustment process is executed.

[0070] If the control unit 101 does not prohibit the execution of the adjustment process, it returns and transports the continuous paper P and resumes image formation on the continuous paper P. This makes it possible to form printed materials that maintain the image quality based on the adjustment process.

[0071] Furthermore, information on the types of paper for which the adjustment process is prohibited may be stored as a list in a storage unit 72, for example.

[0072] An example of the operation of the image forming control in the image forming apparatus 1, configured as described above, will now be explained. Figure 6 is a flowchart showing an example of the operation of the image forming control in the image forming apparatus 1. This control is executed, for example, when a print job based on image formation on continuous paper P is executed.

[0073] As shown in Figure 6, the control unit 101 acquires continuous paper information (step S101). After step S101, the control unit 101 starts printing (step S102). After step S102, the control unit 101 determines whether or not the conditions for image adjustment have been met (step S103).

[0074] If the result of the determination is that the conditions for image adjustment are not met (step S103, NO), the process proceeds to step S108. On the other hand, if the conditions for image adjustment are met (step S103, YES), the control unit 101 determines, based on the continuous paper information, whether or not the continuous paper P is subject to the adjustment process being prohibited (step S104).

[0075] If the determination result is that the continuous paper P is not subject to the adjustment process prohibition (step S104, NO), the control unit 101 executes the adjustment process (step S105). After step S105, the control unit 101 returns the continuous paper P and resumes printing (step S106). After step S106, the process proceeds to step S108.

[0076] Returning to the determination in step S104, if the continuous paper P is subject to the adjustment process prohibition (step S104, YES), the control unit 101 prohibits the adjustment process (step S107). In other words, printing continues without the adjustment process being performed.

[0077] After step S107, the control unit 101 determines whether the print job is complete or not (step S108). If the result of the determination is that the print job is not complete (step S108, NO), the process returns to step S103. On the other hand, if the print job is complete (step S108, YES), this control ends.

[0078] According to this embodiment configured as described above, the execution of adjustment processing is prohibited according to the continuous paper information, so deformation of the continuous paper P caused by return transport can be suppressed. As a result, the wasteful discarding of continuous paper P due to deformation of the continuous paper P can be suppressed, and consequently, printing with stable color tones can be performed.

[0079] In the above embodiment, the continuous paper information was information about the type of continuous paper P, but the present invention is not limited to this. For example, the continuous paper information may be information about the characteristics of the continuous paper P.

[0080] Information regarding the properties of the continuous paper P includes, for example, at least one piece of information on the paper's stiffness, resistance, and basis weight.

[0081] For example, if the stiffness of the continuous paper P is relatively small, if the resistance of the continuous paper P is relatively small, or if the basis weight of the continuous paper P is relatively small, the continuous paper P is prone to deformation after passing through the fixing unit 60 multiple times. In this case, the control unit 101 prohibits the execution of the adjustment process.

[0082] Furthermore, information regarding the characteristics of the continuous paper P may include information about the smoothness of the paper. For example, if the continuous paper P has relatively high smoothness, such as the coated paper described above, passing through the fixing unit 60 multiple times may affect the surface properties and thus the smoothness. Therefore, for example, the control unit 101 may prohibit the execution of the adjustment process if the smoothness of the continuous paper P is relatively high.

[0083] Furthermore, the control unit 101 may prohibit the execution of adjustment processing in addition to continuous paper information, depending on the surrounding environment information of the image forming apparatus 1.

[0084] For example, in high-temperature and high-humidity environmental conditions or low-temperature and low-humidity environmental conditions, expansion and contraction of the continuous paper P is likely to occur, making deformation of the continuous paper P more likely due to passing through the fixing unit 60 multiple times. Therefore, the control unit 101 prohibits the execution of the adjustment process in high-temperature and high-humidity environmental conditions or low-temperature and low-humidity environmental conditions. The environmental information may be information obtainable from, for example, a temperature and humidity sensor capable of acquiring temperature and humidity information.

[0085] Furthermore, in this case, the information regarding the characteristics of the continuous paper P may include information about the paper's moisture content. For example, under high temperature and high humidity environmental conditions, when the paper's moisture content is relatively high, or under low temperature and high humidity environmental conditions, when the paper's moisture content is relatively low, the moisture content of the continuous paper P may be too high or too low. Therefore, in such cases, the control unit 101 prohibits the execution of the adjustment process.

[0086] Furthermore, information regarding the characteristics of the continuous paper P may be obtained from the specifications of the continuous paper P, or, as shown in Figure 72, from a sensor unit 80 capable of obtaining information regarding the characteristics of the continuous paper P. The sensor unit 80 is, for example, a media sensor. The sensor unit 80 may be located, for example, inside the paper feed device 2, or at a position corresponding to the transport path between the paper feed device 2 and the image forming unit 40.

[0087] This allows us to obtain information about the characteristics of the continuous paper P based on its current state.

[0088] Furthermore, in the above embodiment, if the execution of the adjustment process was not prohibited, the continuous paper P was returned and transported, and image formation on the continuous paper P was resumed. However, even if the continuous paper information was information that did not prohibit the execution of the adjustment process, deformation may occur in the portion of the continuous paper P that has passed through the fixing unit 60 multiple times. In this case, it is necessary to change the current continuous paper information of the continuous paper P to information that prohibits the execution of the adjustment process.

[0089] Therefore, for example, the control unit 101 may be capable of acquiring image reading information formed on the continuous paper P. The image reading information includes at least one piece of information such as color shift in the image, color misalignment in the image, wrinkles in the continuous paper P, and distortion of the continuous paper P, and may be acquired by a reading unit 90 such as a scanner, as shown in Figure 8. The reading unit 90 may be provided downstream of the fixing unit 60 of the image forming apparatus 1, or it may be provided in a post-processing device between the image forming apparatus 1 and the winding device 3.

[0090] The control unit 101 modifies the continuous paper information based on the reading information after image formation is resumed. The control unit 101 corresponds to the "modification unit" of the present invention.

[0091] Assume that the type of continuous paper P is ordinary paper and that the adjustment process is not prohibited.

[0092] In this case, if the image adjustment conditions are met, the adjustment process is executed, the paper is returned, and image formation on the continuous paper P is resumed. At this time, if the reading result from the reading unit 90 of the portion that has passed through the fixing unit 60 multiple times is equivalent to an image defect, it is considered that the current continuous paper P may be subject to the prohibition of performing the adjustment process.

[0093] In such cases, the control unit 101 modifies the continuous paper information so that the paper type corresponding to the current continuous paper P is subject to the prohibition of performing the adjustment process.

[0094] An example of the operation of the image forming control of the image forming apparatus 1, which is configured as described above and capable of changing continuous paper information, will now be explained. Figure 9 is a flowchart showing an example of the operation of the image forming control in the modified image forming apparatus 1. Note that this control is similar to the process from steps S101 to S108 in the flowchart shown in Figure 6, for example, and the explanation of the process from steps S101 to S108 will be omitted in the following explanation.

[0095] As shown in Figure 9, after step S106, the control unit 101 acquires reading information from the reading unit 90 and determines whether or not there is deformation in the continuous paper P based on the reading information (step S109). If the determination result is that there is no deformation in the continuous paper P (step S109, NO), the process proceeds to step S108.

[0096] On the other hand, if there is deformation in the continuous paper P (step S109, YES), the control unit 101 changes the continuous paper information (step S110). After step S110, this control ends.

[0097] According to the modified image forming apparatus 1, if deformation occurs in the continuous paper P after printing resumes, based on the read information, the continuous paper information can be modified to prohibit the execution of the adjustment process on the continuous paper P. In this way, continuous paper P that may be deformed by the adjustment process can be effectively excluded from the execution of the adjustment process.

[0098] Furthermore, in the above embodiment, if the adjustment process is prohibited, image formation on the continuous paper P continues without the adjustment process being performed. Therefore, deformation of the continuous paper P caused by return transport can be suppressed, but there is a possibility that the image quality may deteriorate due to the fact that the adjustment process is not performed.

[0099] Therefore, if the print job satisfies the image adjustment conditions, the control unit 101 executes the adjustment process before the print job starts. Furthermore, if the adjustment process is executed before the print job starts, the control unit 101 does not prohibit the execution of the adjustment process, even if the continuous paper information is information that should be subject to the prohibition of the execution of the adjustment process.

[0100] For example, suppose the condition for image adjustment is to execute the adjustment process every time the number of images reaches a predetermined number (e.g., 1000 images). Now, suppose the print job has 800 images, and based on past history information, the condition for image adjustment is met when the print job is in progress and the number of images reaches around 300.

[0101] In this case, the control unit 101 performs adjustment processing before the start of the print job, and after the start of the print job, even if the continuous paper information is information that is subject to the prohibition of performing adjustment processing, it does not prohibit the execution of adjustment processing.

[0102] By doing so, it is possible to suppress the deterioration of image quality caused by the failure to perform adjustment processing.

[0103] Furthermore, suppose a print job contains 2000 images. In this case, the number of images exceeds the predetermined number (1000) required for image adjustment. Therefore, as described above, even if the adjustment process is performed before the print job starts, the number of images will inevitably reach 1000 after the print job starts, making it impossible to complete the print job without satisfying the image adjustment conditions.

[0104] Therefore, the control unit 101 may limit the number of images in a print job to a predetermined number if the number of images in the print job exceeds a predetermined number. The control unit 101 corresponds to the "limiting unit" of the present invention.

[0105] This helps to prevent print jobs that require adjustment processing from being created.

[0106] Furthermore, if the number of images in a print job is limited to a predetermined number, the control unit 101 may inform the user to divide the print job into multiple jobs.

[0107] For example, if the number of images in a print job is 2000 as described above, the control unit 101 will inform the user to split the print job into two jobs, each containing a predetermined number of images, say 1000 images.

[0108] This allows you to prompt the user to execute a print job that does not meet the image adjustment requirements.

[0109] Furthermore, although the above embodiment was an image forming apparatus utilizing electrophotographic process technology, the present invention is not limited thereto, and may, for example, be an image forming apparatus utilizing an inkjet method. In this case, the fixing unit fixes the image to the continuous paper by drying the image formed on the continuous paper.

[0110] Furthermore, the above embodiments are merely examples of how the present invention may be implemented, and the technical scope of the present invention should not be limited by them. In other words, the present invention can be implemented in various ways without departing from its gist or its main features. [Explanation of Symbols]

[0111] 1. Image forming apparatus 2. Paper feed device 3 Winding device 40 Image forming unit 50 Paper transport section 60 Fixing section 80 Sensor section 90 Reading section 101 Control Unit

Claims

1. An image forming unit that forms an image on continuous paper, A fixing unit for fixing the image formed by the image forming unit onto the continuous paper, A transport unit that transports the continuous paper from the image forming unit toward the fixing unit, An adjustment control unit that performs the adjustment process by the image forming unit and, when the adjustment process is performed, controls the transport unit to return and transport the continuous paper, A prohibition control unit that controls whether or not to prohibit the execution of the adjustment process according to the continuous paper information, An image forming apparatus equipped with the following features.

2. The prohibition control unit controls whether or not to prohibit the execution of the adjustment process if a request to execute the adjustment process is received in the middle of a print job. The image forming apparatus according to claim 1.

3. The continuous paper information includes information regarding the type of continuous paper, The image forming apparatus according to claim 1.

4. The continuous paper information includes information regarding the characteristics of the continuous paper, The image forming apparatus according to claim 1.

5. It includes a sensor unit capable of acquiring information regarding the characteristics of the continuous paper, The image forming apparatus according to claim 4.

6. The information relating to the characteristics of the continuous paper is at least one of the following: moisture content, smoothness, stiffness, resistance, and basis weight. The image forming apparatus according to claim 5.

7. The prohibition control unit prohibits the execution of the adjustment process if the type of continuous paper is a film material. The image forming apparatus according to claim 3.

8. If the adjustment control unit does not prohibit the execution of the adjustment process by the prohibition control unit, the adjustment control unit returns and transports the continuous paper and resumes image formation on the continuous paper. The image forming apparatus according to claim 1.

9. An acquisition unit capable of acquiring reading information of an image formed on the continuous paper, A modification unit that modifies the continuous paper information based on the reading information after the resumption of the image formation process, Furthermore, The image forming apparatus according to claim 8.

10. The reading information includes at least one piece of information: color shift in the image, color misalignment in the image, wrinkles in the continuous paper, and distortion of the continuous paper. The image forming apparatus according to claim 9.

11. The adjustment control unit executes the adjustment process before the start of the print job if the print job satisfies the image adjustment conditions. The prohibition control unit shall not prohibit the execution of the adjustment process if the adjustment process is performed before the start of the print job. The image forming apparatus according to claim 1.

12. If the number of images in a job exceeds a predetermined number, the system further includes a limiting unit that limits the number of images in the job to the predetermined number. The image forming apparatus according to claim 1.

13. The adjustment process is at least one of image stabilization and color shift correction. The image forming apparatus according to claim 1.

14. A method for controlling the prohibition of an image forming apparatus, comprising an image forming unit for forming an image on continuous paper, and a fixing unit for fixing the image formed by the image forming unit onto the continuous paper, The continuous paper is transported from the image forming unit toward the fixing unit, The image forming unit performs the adjustment process, and when the adjustment process is performed, the continuous paper is controlled to be returned and transported. It has, The system further includes controlling whether or not to prohibit the execution of the adjustment process in accordance with the continuous paper information between transporting the continuous paper and returning it. Prohibition control method.

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