Image forming apparatus

Abstract

To enable supply of recording paper to prevent interruption of adjustment processing even when the recording paper cannot be supplied for image formation from a paper feeding unit that supplies recording paper for the adjustment processing.SOLUTION: An image forming apparatus 10 comprises: a plurality of paper feed cassettes 71-75 that supply recording paper; an image forming unit 12 that executes, on the recording paper, image formation or adjustment processing that is image formation for adjustment set in advance; an operating unit 21 to which an instruction is input by a user; and a control unit 29 that, during the execution of the adjustment processing, causes a predetermined paper feeding unit for adjustment processing to supply the recording paper, the paper feeding unit for adjustment processing set with attribute information matching a condition necessary for the execution of the adjustment processing, and causes the image forming unit 12 to execute the adjustment processing. When the recording paper cannot be supplied from the paper feeding unit for adjustment processing during the execution of the adjustment processing, the control unit 29 causes an alternative paper feeding unit set in advance as an alternative paper feeding unit for adjustment processing to supply the recording paper used for the adjustment processing.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to an image forming apparatus that performs an adjustment process, which is image formation or image formation for a preset adjustment, on recording paper supplied by a paper supply unit, and in particular to a technique for setting the paper supply unit that supplies the recording paper used in the adjustment process. [Background technology]

[0002] Image forming devices include electrophotographic systems that deposit toner on recording paper to form an image on the recording paper, and inkjet systems that eject ink onto the recording paper to form an image on the recording paper, etc. In electrophotographic systems, an adjustment process is performed in which a pattern is formed on the recording paper to adjust the image density, while in inkjet systems, an adjustment process is performed in which ink in an ink head is ejected onto the recording paper.

[0003] The recording device described in Patent Document 1 has cassettes each containing a plurality of types of recording media, and determines the recording medium (e.g., the widest recording medium) on which to record the test pattern based on the priority of the recording medium size and the priority of the recording medium type, selects the cassette containing this recording medium, supplies the recording medium from the selected cassette, and records the test pattern on this recording medium. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2020-37210 A Summary of the Invention [Problem to be solved by the invention]

[0005] Here, when the above-mentioned adjustment process is performed, a paper feed unit that contains recording paper of a type and size suitable for the adjustment process is selected from among a plurality of paper feed units (such as paper feed cassettes), and recording paper is supplied from this selected paper feed unit. In Patent Document 1, a recording medium on which a test pattern is recorded is determined based on the priority order of the recording medium size and the priority order of the recording medium type, a cassette containing this recording medium is selected, and the recording medium is supplied from this selected cassette. However, when an error occurs in the paper feed unit, it is not possible to deal with this, and the adjustment process is interrupted.

[0006] The present invention has been developed in consideration of the above-mentioned circumstances, and aims to enable the supply of recording paper, thereby preventing the adjustment process from being interrupted, even in the event that a situation arises in which it is not possible to supply recording paper for image formation from a paper feed section that supplies recording paper for the adjustment process. [Means for solving the problem]

[0007] An image forming apparatus according to one aspect of the present invention comprises a plurality of paper feeding units that supply recording paper, an image forming unit that performs an adjustment process, which is image formation or image formation for a preset adjustment, on the recording paper supplied by the paper feeding units, an operation unit to which instructions are input by a user, and a control unit that, when performing the adjustment process, causes recording paper to be supplied from a predetermined paper feeding unit for adjustment process that is set with attribute information that matches the conditions necessary for performing the adjustment process, and causes the image forming unit to perform the adjustment process, and if recording paper cannot be supplied from the paper feeding unit for adjustment process when performing the adjustment process, the control unit causes the recording paper to be used in the adjustment process to be supplied from an alternative paper feeding unit that is preset as an alternative paper feeding unit for adjustment process. Effect of the Invention

[0008] According to the present invention, even if a situation occurs in which it is not possible to supply recording paper for image formation from the paper feed section that supplies recording paper for the adjustment process, it is possible to prevent the adjustment process from being interrupted by making it possible to supply recording paper. [Brief description of the drawings]

[0009] [Figure 1] 1 is a cross-sectional view showing an image forming apparatus according to a first embodiment of the present invention. [Diagram 2] 1 is a block diagram showing a main internal configuration of an image forming apparatus; [Diagram 3] 11 is a flowchart showing a process for setting any one of a print job paper feed unit, an adjustment processing paper feed unit, and an alternative paper feed unit that supplies recording paper during image formation based on a print job. [Figure 4] FIG. 4 is a diagram showing an initial screen displayed on a display unit of the image forming apparatus. [Diagram 5] FIG. 4 is a diagram showing a paper feed selection screen displayed on a display unit of the image forming apparatus. [Figure 6] 13 is a diagram showing a paper feed setting window for adjustment process setting displayed on a display unit of the image forming apparatus. FIG. [Figure 7] 13 is a diagram showing a paper feed setting window for a print job (or an alternative) displayed on a display unit of the image forming apparatus. FIG. [Figure 8] 13 is a diagram conceptually showing a data table in which attribute information of each paper feed cassette is written. FIG. [Figure 9] 10 is a flowchart showing a process flow when performing an adjustment process. [Figure 10] FIG. 13 is a diagram showing an adjustment process execution screen displayed on a display unit of the image forming apparatus. [Figure 11] FIG. 13 is a diagram showing an error display screen displayed on a display unit of the image forming apparatus. [Figure 12] FIG. 13 is a diagram showing an error display screen displayed on a display unit of the image forming apparatus. [Figure 13] FIG. 4 is a cross-sectional view showing an image forming apparatus according to a second embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. First Embodiment Fig. 1 is a cross-sectional view showing an image forming apparatus according to a first embodiment of the present invention. As shown in Fig. 1, the image forming apparatus 10 is an MFP (multi-function peripheral) having multiple functions such as a copy function and a scanner function. The image forming apparatus 10 includes an image reading unit 11 and an image forming unit 12.

[0011] The image reading unit 11 has an image pickup element (CCD sensor, contact image sensor, etc.) that optically reads an image of a document, and image data representing the image of the document is generated from the analog output of this image pickup element.

[0012] The image forming unit 12 forms an image represented by the image data on a recording paper by electrophotography, and includes a magenta image forming unit 3M, a cyan image forming unit 3C, a yellow image forming unit 3Y, and a black image forming unit 3Bk. In each of the image forming units 3M, 3C, 3Y, and 3Bk, the surface of the photosensitive drum 4 is uniformly charged, the surface of the photosensitive drum 4 is exposed to light, an electrostatic latent image is formed on the surface of the photosensitive drum 4, the electrostatic latent image on the photosensitive drum 4 is developed into a toner image, and the toner image on the photosensitive drum 4 is transferred to the intermediate transfer belt 5. As a result, a color toner image is formed on the intermediate transfer belt 5. This color toner image is secondarily transferred to the recording paper P transported from the paper feeder 14 through the transport path 8 in the nip area N between the intermediate transfer belt 5 and the secondary transfer roller 6.

[0013] The paper feed device 14 includes a first paper feed cassette 71, a second paper feed cassette 72, a third paper feed cassette 73, a fourth paper feed cassette 74, a fifth paper feed cassette 75, and a manual feed tray 9, and the recording paper P is fed and transported from one of the paper feed cassettes 71 to 75 to the transport path 8, or the recording paper P is fed and transported from the manual feed tray 9 to the transport path 8. The recording paper P is sent to the transport path 8, and the color toner image on the intermediate transfer belt 5 is secondarily transferred to the recording paper P in the nip area N between the intermediate transfer belt 5 and the secondary transfer roller 6. The first paper feed cassette 71, the second paper feed cassette 72, the third paper feed cassette 73, the fourth paper feed cassette 74, and the manual feed tray 9 are examples of a paper feed section in the claims.

[0014] Thereafter, the recording paper P is heated and pressed in the fixing device 15 so that the toner image on the recording paper P is fixed by thermocompression, and the recording paper P is then discharged onto a paper discharge tray 17 via paper discharge rollers 16 .

[0015] Fig. 2 is a block diagram showing the internal configuration of the image forming apparatus 10. As shown in Fig. 2, the image forming apparatus 10 includes an image reading section 11, an image forming section 12, an operation section 21, a display section 22, a touch panel 24, a storage section 26, each of the paper feed cassettes 71 to 75, and a control unit 28. These components are capable of transmitting and receiving data or signals to and from each other via a bus.

[0016] The operation unit 21 includes physical keys such as a numeric keypad, a decision key, a start key, etc. The display unit 22 includes a liquid crystal display (LCD: Liquid Crystal Display), an organic light-emitting diode (OLED: Organic Light-Emitting Diode) display, or the like.

[0017] A touch panel 24 is disposed on the screen of the display section 22. The touch panel 24 is a so-called resistive film type or capacitive type touch panel, which detects contact (touch) of a user's finger or the like on the touch panel 24 together with the contact position, and outputs a detection signal indicating the coordinates of the contact position to a control section 29 of the control unit 28, which will be described later. Note that the touch panel 24 is considered to be a part of the operation section 21.

[0018] The storage unit 26 is a large-capacity storage device such as a solid state drive (SSD) or a hard disk drive (HDD), and stores various application programs and various data.

[0019] The control unit 28 is composed of a processor, a RAM (Random Access Memory), a ROM (Read Only Memory), etc. The processor is, for example, a CPU (Central Processing Unit), an ASIC, or an MPU (Micro Processing Unit), etc. The control unit 28 functions as a control unit 29 by the processor executing a control program stored in the ROM or the storage unit 26.

[0020] The control unit 29 comprehensively controls the image forming apparatus 10. The control unit 29 is connected to the image reading unit 11, the image forming unit 12, the operation unit 21, the display unit 22, the touch panel 24, the storage unit 26, and each of the paper feed cassettes 71 to 75, and controls the operation of these components and transmits and receives signals or data to and from each of the components.

[0021] The control unit 29 serves as a processing unit that executes various processes required for image formation by the image forming apparatus 10. The control unit 29 also accepts operation instructions input by the user based on a detection signal output from the touch panel 24 or an operation of a physical key of the operation unit 21. For example, the control unit 29 accepts a touch operation on a GUI (Graphical User Interface) or the like displayed on the screen of the display unit 22 through the touch panel 24. Furthermore, the control unit 29 has a function of controlling the display operation of the display unit 22.

[0022] Furthermore, the control unit 29 controls the driving sources (motors, etc.) that operate the respective paper feed cassettes 71-75 to transport and supply the recording paper P from any of the paper feed cassettes 71-75 to the transport path 8.

[0023] In the image forming apparatus 10 having such a configuration, the control unit 29 performs image forming operations such as reading the image of the original document using the image reading unit 11, supplying recording paper from either one of the paper feed cassettes 71-75 of the paper feed device 14 or the manual feed tray 9, inputting image data representing the image of the original document to the image forming unit 12 based on a printing job, and causing the image forming unit 12 to form the image of the original document on the supplied recording paper.

[0024] In addition, the control unit 29 counts the number of recording sheets on which an image is formed by the image forming unit 12, and when this counted number reaches a preset threshold value, executes an adjustment process in which recording sheets are supplied from any of 71-75 of the paper feed device 14 or from the manual feed tray 9, image data indicating preset patterns of each color, black, yellow, cyan, and magenta, is input to the image forming unit 12, and the image forming unit 12 forms a pattern of each color on the recording sheets.

[0025] For example, the user looks at the patterns of each color formed on the recording paper, and operates operation unit 21 to input an adjustment amount for the density of each color component of the image formed on the recording paper by image forming unit 12. Based on the adjustment amount for the density of each color component input to operation unit 21, control unit 29 controls image forming unit 12 to correct the density of each color component of the image formed on the recording paper by image forming unit 12. Alternatively, the user causes image reading unit 11 to read the patterns of each color formed on the recording paper. Control unit 29 determines the density of the patterns of each color read by image reading unit 11, and based on the determined density of each color component, controls image forming unit 12 to correct the density of each color component of the image formed on the recording paper.

[0026] Here, in the image forming apparatus 10, the control unit 29 controls the recording paper used for image formation by the print job or the recording paper used for image formation in the adjustment process to be supplied from any of the paper feed cassettes or the manual feed tray, since the image forming apparatus 10 is provided with four paper feed cassettes, namely, a first paper feed cassette 71, a second paper feed cassette 72, a third paper feed cassette 73, a fourth paper feed cassette 74, a fifth paper feed cassette 75, and a manual feed tray 9. Here, there are two types of adjustment processes, type I and type II. Type I of adjustment process is an adjustment process in which the size and layout of the patterns of each color, black, yellow, cyan, and magenta, formed on the recording paper are adapted to the standard size "A4". Type II of adjustment process is an adjustment process in which the size and layout of the patterns of each color, formed on the recording paper, are adapted to the standard size "A3".

[0027] Patterns of each color that are compatible with the standard size "A4" of adjustment process type I, and patterns of each color that are compatible with the standard size "A3" of adjustment process type II are pre-stored in memory unit 26, and are read out from memory unit 26 by control unit 29 and used in the adjustment process.

[0028] In the image forming apparatus 10, the control unit 29 sets each of the first paper feed cassette 71, the second paper feed cassette 72, the third paper feed cassette 73, the fourth paper feed cassette 74, the fifth paper feed cassette 75, and the manual feed tray 9 as either a print job paper feed unit that supplies recording paper for image formation based on a print job, an adjustment process paper feed unit that supplies recording paper for image formation when an adjustment process is being performed, or an alternative adjustment process paper feed unit that supplies recording paper when the adjustment process paper feed unit cannot supply recording paper when an adjustment process is being performed. The control unit 29 stores each of the settings in, for example, a nonvolatile memory or the like built into the control unit 28.

[0029] Next, the process of setting each paper feed cassette 71-75 or manual feed tray 9 as either a paper feed section for a print job that supplies recording paper during image formation based on a print job, a paper feed section for adjustment processing, or an alternative paper feed section will be described with reference to the flowchart shown in Figure 3.

[0030] A user places recording paper of, for example, a standard size in each of the paper feed cassettes 71 to 75. Here, it is assumed that the first paper feed cassette 71 holds recording paper of standard size "A4" plain paper, the second paper feed cassette 72 holds recording paper of standard size "A3" plain paper, the third paper feed cassette 73 holds recording paper of standard size "A4" plain paper, the fourth paper feed cassette 74 holds recording paper of standard size "A3" plain paper, and the fifth paper feed cassette 75 holds recording paper of standard size "A3" recycled paper.

[0031] The control unit 29 causes the display unit 22 to display an initial screen G1 as shown in Fig. 4, for example. A plurality of function keys 31a to 31h, each associated with a different function, are displayed on the initial screen G1. When the user touches the function key 31h indicating the paper feed setting mode, the control unit 29 receives an instruction to start the paper feed setting mode associated with the function key 31h via the touch panel 24, and causes the display unit 22 to display a paper feed selection screen G2 as shown in Fig. 5 (S101).

[0032] On the paper feed selection screen G2, for each of the first paper feed cassette 71, the second paper feed cassette 72, the third paper feed cassette 73, the fourth paper feed cassette 74, the fifth paper feed cassette 75, and the manual feed tray 9, there are displayed a button B1 for accepting an instruction to use the paper feed cassette etc. as a paper feed section for adjustment processing, a button B2 for accepting an instruction to use the paper feed cassette etc. as a paper feed section for a print job, and a button B3 for accepting an instruction to use the paper feed cassette etc. as an alternative paper feed section.

[0033] For example, when the control unit 29 detects through the touch panel 24 that the user has operated button B1 for any of the paper feed cassettes on the paper feed selection screen G2 (S102 "Adjustment"), the control unit 29 accepts an instruction to select the paper feed cassette corresponding to the operated button B1 as the paper feed unit for adjustment processing (S103). Here, as an example, it is assumed that the control unit 29 has accepted an instruction to select the third paper feed cassette 73 as the paper feed unit for adjustment processing. The control unit 29 displays a paper feed setting window W1 for adjustment processing setting, as shown in FIG. 6 (S104).

[0034] The paper feed setting window W1 for the adjustment process displays a size selection button T11 for receiving instructions to set the standard size of the recording paper to be stored in the paper feed cassette, a type selection button T12 for receiving instructions to set the type of recording paper, and an OK key K11.

[0035] When the user touches the size selection button T11, the control unit 29 receives a pull-down display instruction via the touch panel 24, and causes buttons indicating each standard size to be displayed in a pull-down menu. The user touches the button portion indicating the standard size of the recording paper to be stored in the third paper feed cassette 73 (the paper feed portion selected as the paper feed portion for adjustment processing), for example, "A4," from among the standard sizes displayed in the pull-down menu. The control unit 29 accepts the standard size displayed in the portion touched as the standard size of the recording paper to be stored in the paper feed cassette (S105).

[0036] Furthermore, when the user touches text box T12, control unit 29 receives a pull-down display instruction via touch panel 24 and causes buttons indicating predetermined types of recording paper to be displayed in a pull-down menu. The user touches the button indicating the type of recording paper to be stored in third paper feed cassette 73 (the paper feed unit selected as the paper feed unit for adjustment processing), for example "plain paper," from among the types displayed in the pull-down menu. Control unit 29 accepts the type displayed in the touched area as the type of recording paper to be stored in the paper feed cassette (S106).

[0037] The control unit 29 stores "A4" as the standard size of the recording paper accepted in S106 and plain paper as the type accepted in S107 for the third paper feed cassette 73 accepted as the paper feed unit for adjustment processing in a data table DT such as the example shown in Figure 8 as attribute information of the paper feed unit for adjustment processing (S109).

[0038] Furthermore, when the control unit 29 detects through the touch panel 24 that the user has operated button B3 for any of the paper feed cassettes on the paper feed selection screen G2 (S102 "Alternative"), the control unit 29 accepts an instruction to select the paper feed cassette corresponding to the operated button B3 as an alternative paper feed unit (S110). Here, as an example, it is assumed that the control unit 29 has accepted an instruction to select the fifth paper feed cassette 75 as an alternative paper feed unit. The control unit 29 displays a paper feed setting window W2 for alternative settings as shown in FIG. 7 (S111).

[0039] The alternative paper feed setting window W2 displays a size selection button T21 for receiving an instruction to set the standard size of the recording paper to be stored in the alternative paper feed cassette, a type selection button T22 for receiving an instruction to set the type of recording paper, and an OK key K23.

[0040] When the user touches the size selection button T21, the control unit 29 receives a pull-down display instruction via the touch panel 24, and causes buttons indicating each standard size to be displayed in a pull-down menu. The user touches the button portion indicating the standard size of the recording paper to be stored in the fifth paper feed cassette 75 (the paper feed portion selected as the alternative paper feed portion), for example, "A3," from among the standard sizes displayed in the pull-down menu. The control unit 29 accepts the standard size displayed in the portion touched as the standard size of the recording paper to be stored in the paper feed cassette (S112).

[0041] Furthermore, when the user touches text box T22, control unit 29 receives a pull-down display instruction via touch panel 24 and causes buttons indicating predetermined types of recording paper to be displayed in a pull-down menu. The user touches the button indicating the type of recording paper to be stored in fifth paper feed cassette 75 (the paper feed unit selected as the alternative paper feed unit), for example, "recycled paper," from among the types displayed in the pull-down menu. Control unit 29 accepts the type displayed in the touched area as the type of recording paper to be stored in the paper feed cassette (S113).

[0042] The control unit 29 stores in the data table DT as attribute information of the alternative paper feed unit, for the fifth paper feed cassette 73 accepted as the alternative paper feed unit in S110, "A3" as the standard size of the recording paper accepted in S112, and recycled paper as the type accepted in S113 (S115).

[0043] When the control unit 29 detects through the touch panel 24 that the user has operated button B2 for any of the paper feed cassettes, etc. on the paper feed selection screen G2 (S102 ``Print''), the control unit 29 accepts an instruction to select the paper feed cassette corresponding to the operated button B2 as the paper feed unit for the print job.In this case, too, the attribute information of the paper feed unit for the print job is set and stored in the same manner as when an alternative paper feed unit is accepted.

[0044] In the data table DT shown in FIG. 8, for the first paper feed cassette 71, a print job, a standard size of the recording paper, "A4", and a type of the recording paper, "plain paper", are stored, and for the second paper feed cassette 72, a print job, a standard size of the recording paper, "A3", and a type of the recording paper, "plain paper", are stored. For the third paper feed cassette 73, an adjustment process, a standard size of the recording paper, "A4", and a type of the recording paper, "plain paper", are stored, and for the fourth paper feed cassette 74, an adjustment process, a standard size of the recording paper, "A3", and a type of the recording paper, "plain paper", are stored. For the fifth paper feed cassette 75, an alternative, a standard size of the recording paper, "A3", and a type of the recording paper, "recycled paper", are stored. For the manual feed tray 9, a print job, a standard size of the recording paper, "A4", and a type of the recording paper, "plain paper", are stored.

[0045] The print job, adjustment process, substitution, standard size of recording paper, and type of recording paper in the data table DT constitute attribute information in the claims.

[0046] In this way, the attribute information of the paper feed cassettes 71 to 75 and the manual feed tray 9 is written into the data table DT, and then the process of the flowchart shown in FIG. 3 ends.

[0047] In this example, the standard size of the recording paper stored in each paper feed cassette 71-75 is input in the paper feed setting window W1 or W2, but it is also possible to provide known recording paper size detection sensors for detecting the standard size of each recording paper stored in each paper feed cassette 71-75, and have the control unit 29 accept the standard sizes of each recording paper detected by these sensors as the recording paper sizes stored in each paper feed cassette.

[0048] Next, the process for executing the adjustment process will be described with reference to a flowchart shown in FIG 9.

[0049] The control unit 29 counts the number of sheets of recording paper on which the image forming unit 12 has formed an image based on the print job, and when the counted number reaches a preset threshold (YES in S201), the control unit 29 displays an adjustment process execution screen G11, for example, as shown in FIG. 10, on the display unit 22 (S202). The adjustment process execution screen G11 displays a function key 310 indicating the execution of an adjustment process, and the like. When the user touches the function key 310 indicating the execution of an adjustment process, the control unit 29 accepts an instruction to execute the adjustment process through the touch panel 24 (YES in S203). Note that, if the control unit 29 does not accept an instruction to execute the adjustment process within a certain period (for example, one minute) after the display of the adjustment process execution screen G11 (NO in S203), it ends the process. Note that, if the counted number does not reach a preset threshold (NO in S201), the control unit 29 repeats the process of S201.

[0050] When the control unit 29 receives an instruction to execute the adjustment process, it detects a paper feed unit for adjustment process in which attribute information including a set value that matches the content of the adjustment process to be executed at this time is set (S205). For example, when the above-mentioned type II is set as the adjustment process to be executed, the control unit 29 refers to the data table DT to detect a paper feed unit for adjustment process in which attribute information including a set value that matches the recording paper size and type indicated by type II is set. The control unit 29 detects, for example, the fourth paper feed cassette 74 associated with type II of the adjustment process. It is assumed that whether type I or type II of the adjustment process is executed is set in advance based on the usage status of the image forming apparatus 10 (such as the frequency of use of each standard size). It is also assumed here that, when multiple paper feed units for adjustment process are set, different attribute information is set for each of them.

[0051] Then, the control unit 29 judges whether the adjustment process paper feed unit detected in S205 is in a state where it cannot feed recording paper, that is, whether an error has occurred (S208). An error in the adjustment process paper feed unit is, for example, a state where no recording paper is stored in the adjustment process paper feed unit, a state where the adjustment process paper feed unit is not operating due to a malfunction, etc. If the adjustment process paper feed unit does not discharge recording paper even when the control unit 29 controls the adjustment process paper feed unit to operate, or if the recording paper pulled out from the adjustment process paper feed unit is not detected by a known paper detection sensor installed downstream of the adjustment process paper feed unit in the recording paper transport direction, the control unit 29 judges that an error has occurred in the adjustment process paper feed unit.

[0052] Here, if the control unit 29 determines that no error has occurred (S208 "No"), it causes the fourth paper feed cassette 74 (adjustment processing paper feed unit) to supply recording paper of the standard size "A3", reads out from the memory unit 26 patterns of each color that are suitable for the standard size "A3" of adjustment processing type II, and causes the image forming unit 12 to form the patterns of each color on recording paper of the standard size "A3" (S209). After this, the process ends.

[0053] The standard size "A3" recording paper on which the patterns of each color are formed is used to adjust the density of each color component of the image formed on the recording paper by the image forming unit 12 as described above.

[0054] Furthermore, when the control unit 29 determines that an error has occurred in the fourth paper feed cassette 74 (adjustment processing paper feed unit) detected in S205 (S208 "Yes"), it refers to the data table DT and selects a paper feed cassette, etc. set as an alternative paper feed unit (S210). Here, it is assumed that the fifth paper feed cassette 75 has been selected as the paper feed cassette, etc. set as the alternative paper feed unit. Then, the control unit 29 determines whether the attribute information set in the fifth paper feed cassette 75 (alternative paper feed unit) includes a setting value that matches the content of the adjustment processing to be executed at this time (S211). That is, when the recording paper size required for executing the adjustment processing matches the standard size of recording paper set in the fifth paper feed cassette 75 (alternative paper feed unit), the control unit 29 determines that the recording paper of the fifth paper feed cassette 75 can be applied, and when they do not match, it determines that the recording paper is not applicable.

[0055] In this case, the standard size "A3" required to execute the adjustment process matches the standard size "A3" of the recording paper indicated by the attribute information set in the fifth paper feed cassette 75 (alternative paper feed unit), so the control unit 29 determines that the recording paper of the fifth paper feed cassette 75 can be used (S211 "Yes"), causes the fifth paper feed cassette 75 to supply recording paper of the standard size "A3", reads out from the storage unit 26 patterns of each color that are suitable for the standard size "A3" of adjustment process type II, and causes the image forming unit 12 to form the patterns of each color on recording paper of the standard size "A3" (S209). After this, the control unit 29 resumes the print job and returns to S201.

[0056] Furthermore, assuming that the fifth paper feed cassette 75 serving as an alternative paper feed section contains recording paper of the standard size "A4" and that the standard size "A4" is stored in association with the fifth paper feed cassette 75 in the data table DT, the control section 29 determines that it is not possible to use the recording paper of the fifth paper feed cassette 75 because the standard size "A4" of the recording paper of the fifth paper feed cassette 75 does not match the standard size "A3", which is the recording paper size required to perform the adjustment process (S211 "No").

[0057] At this time, the control unit 29 causes the display unit 22 to display an error display screen G30 indicating that an error has occurred in the alternative paper feed unit, as shown in Fig. 11 (S212). The paper feed cassette etc. error display screen G30 shown in Fig. 11 displays a message E1 indicating that an error has occurred in the paper feed cassette etc. and that the paper feed cassette etc. will be changed.

[0058] In this case, the control unit 29 refers to the data table DT and detects another paper feed cassette, etc. that contains recording paper of the standard size "A3", which is the recording paper size required to execute the adjustment process, i.e., a paper feed cassette, etc. that is set as a paper feed unit for the print job and has attribute information set that includes a setting value that matches the contents of the adjustment process (S213).

[0059] If there is a print job paper feed unit for which attribute information including a set value matching the content of the adjustment process is set (S213 "Yes"), the control unit 29 selects this print job feed unit (for example, the second paper feed cassette 72) as a paper feed cassette or the like that will supply recording paper used in image formation in the adjustment process (S214). The control unit 29 causes the selected paper feed cassette or the like, in this example the second paper feed cassette 72, to supply recording paper of the standard size "A3", reads out from the storage unit 26 patterns of each color that are suitable for the standard size "A3" of the adjustment process type II, and causes the image forming unit 12 to form the patterns of each color on recording paper of the standard size "A3" (S209). After this, the process ends.

[0060] Furthermore, if there is no print job paper feed unit for which attribute information including a setting value matching the content of the adjustment process is set (S213 "No"), the control unit 29 causes the display unit 22 to display a paper feed cassette error display screen G31 as shown in Fig. 12 (S215). The paper feed cassette error display screen G31 shown in Fig. 12 displays a message E2 indicating that the adjustment process will not be executed due to an error in the paper feed cassette. After this, the process ends.

[0061] In this way, in image forming apparatus 10, during adjustment processing, a paper feed unit for adjustment processing is selected based on data table DT, recording paper is supplied from the selected paper feed cassette or the like, and image formation in the adjustment processing is performed on the supplied recording paper by image forming unit 12. If an error occurs in the selected paper feed unit for adjustment processing, recording paper is supplied from an alternative paper feed unit or a paper feed unit for a print job in which attribute information including a setting value matching the contents of the adjustment processing is set based on data table DT, and image formation in the adjustment processing is performed on the supplied recording paper by image forming unit 12.

[0062] As a result, according to the image forming device 10, even if a situation occurs in which the paper feed section that supplies recording paper for the adjustment process is unable to supply recording paper for image formation, it is possible to supply recording paper, thereby preventing the adjustment process from being interrupted.

[0063] Furthermore, depending on the user's operation, each of the paper feed cassettes 71 to 75 can be used to supply recording paper for a print job, for supplying recording paper for adjustment processing, or for supplying alternative recording paper.

[0064] <Second embodiment> Fig. 13 is a cross-sectional view showing an image forming apparatus according to a second embodiment of the present invention. In Fig. 13, parts that perform the same functions as those in Fig. 1 are given the same reference numerals and their description will be omitted.

[0065] The image forming apparatus 10A of the second embodiment includes an image reading unit 11 and an image forming unit 12A. The image reading unit 11 has an image sensor that optically reads an image of a document, and image data representing the image of the document is generated from an analog output of the image sensor.

[0066] The image forming unit 12A forms an image represented by the image data on recording paper by an inkjet method, and has line heads (an example of an ink head) 55 that eject ink droplets of four colors (black, cyan, magenta, and yellow). Each line head 55 ejects ink droplets of the corresponding color onto the recording paper P that has been transported from the paper feeder 14 to the transport unit 54 through the transport path 53, forming a color image on the recording paper P.

[0067] The transport unit 54 includes a drive roller 68, a driven roller 69, a tension roller 65, and a transport belt 66. The transport belt 66 is an endless belt that is stretched across the drive roller 68, the driven roller 69, and the tension roller 65. The drive roller 68 is a roller that is driven to rotate clockwise by a motor (not shown), and as the drive roller 68 is driven to rotate, the transport belt 66 is moved in a clockwise orbit, and the driven roller 69 and the tension roller 65 are driven to rotate clockwise.

[0068] The tension roller 65 is a roller for maintaining an appropriate tension of the conveyor belt 66. The adsorption roller 67 is in contact with the conveyor belt 66 and electrostatically adsorbs the recording paper P fed from the paper feeder 14 to the conveyor belt 66 by charging the conveyor belt 66.

[0069] The recording paper P on which the image of the original has been formed by the image forming unit 12A passes through a relay transport path and is discharged onto a discharge tray 63 via a driven roller 69.

[0070] The paper feeding device 14 is equipped with a first paper feeding cassette 71, a second paper feeding cassette 72, a third paper feeding cassette 73, a fourth paper feeding cassette 74, and a fifth paper feeding cassette 75, and recording paper P is transported and supplied to the transport path 53 from any of the paper feeding cassettes 71 to 75.

[0071] Next, a configuration relating to control of the image forming apparatus 10A of the second embodiment will be described. The configuration relating to control of the image forming apparatus 10A is generally the same as that of the image forming apparatus 10 of the first embodiment shown in FIG. 2. However, the image forming apparatus 10A of the second embodiment differs from the first embodiment in that an inkjet type image forming section 12A is used instead of the electrophotographic type image forming section 12. A control section 29 of the image forming apparatus 10A of the second embodiment controls the inkjet type image forming section 12A to perform a print job in which an image of an original is formed on recording paper by the image forming section 12A in the above-mentioned procedure.

[0072] In addition, the control unit 29 counts the number of recording sheets on which an image is formed by the image forming unit 12A, and when the counted number reaches a preset threshold, performs an adjustment process in which ink is purged onto the recording sheet by each line head 55 of the image forming unit 12A (purging). This purging of ink is performed to prevent the nozzles of each line head 55 from clogging.

[0073] The image forming apparatus 10A of the second embodiment differs from the image forming apparatus 10 of the first embodiment in that an inkjet type image forming unit 12A is used instead of an electrophotographic type image forming unit 12, but the processes shown in Figures 3 and 9 are performed in the same manner as in the image forming apparatus 10, and the recording paper to be adjusted is supplied by any of the paper feed cassettes 71 to 75 or the manual feed tray 9.

[0074] The present invention is not limited to the configurations of the above-mentioned embodiments, and various modifications are possible. The configurations and processes of the above-mentioned embodiments described with reference to Figures 1 to 13 are merely examples of the present invention, and are not intended to limit the present invention to these configurations and processes. [Explanation of symbols]

[0075] 10 Image forming device 10A Image forming device 11 Image reading unit 12 Image forming section 12A Image forming section 14 Paper feeder 21 Control section 22 Display section 24 Touch Panel 26 Memory section 28 Control Unit 29 Control Unit 71 First paper feed cassette 72 Second paper feed cassette 73 Third paper feed cassette 74 4th paper feed cassette 75 5th paper feed cassette

Claims

1. A plurality of paper feed units for supplying recording paper; an image forming unit that performs an adjustment process, which is image formation or preset image formation for adjustment, on the recording paper supplied by the paper feed unit; an operation unit into which instructions are input by a user; a control unit that, when performing the adjustment process, causes recording paper to be supplied from a predetermined adjustment process paper feed unit in which attribute information that matches a condition required for performing the adjustment process is set, and causes the image forming unit to perform the adjustment process; An image forming device, wherein when recording paper cannot be supplied from the adjustment process paper supply unit when the adjustment process is being performed, the control unit causes an alternative paper supply unit that is pre-set as an alternative adjustment process paper supply unit to supply recording paper to be used in the adjustment process.

2. The image forming apparatus according to claim 1 , wherein the control unit presets the alternative paper feed unit in accordance with an instruction input to the operation unit.

3. Attribute information indicating a size of the recording paper fed by the paper feed unit is set for each of the paper feed units, 2. The image forming apparatus according to claim 1, wherein the control unit selects the alternative paper feed unit when paper cannot be supplied from the paper feed unit for adjustment processing, on the condition that attribute information identical to attribute information set in the paper feed unit for adjustment processing is set in the alternative paper feed unit.

4. A display unit is provided, 2. The image forming apparatus according to claim 1, wherein, when an error occurs that prevents the alternative paper feed section from supplying recording paper, the control section causes the display section to display the occurrence of the error.

5. The image forming apparatus according to claim 1 , wherein the control unit presets the adjustment process paper feed unit in accordance with an instruction input to the operation unit.

6. the image forming unit forms an image on a recording sheet by an electrophotographic method; 2. The image forming apparatus according to claim 1, wherein the adjustment process is a process of forming a preset pattern on a recording sheet by the image forming section.

7. the image forming unit forms an image on a recording sheet by an inkjet method; 2. The image forming apparatus according to claim 1, wherein the adjustment process is a process of causing the image forming unit to spit ink onto the recording paper.

Images