Image forming apparatus and method for operating image forming apparatus

Abstract

To reduce the time required for replacement of a fixing unit.SOLUTION: An image forming apparatus comprises a control section, a display section, a removable fixing unit, and a temperature measuring section that measures the temperature of or near the fixing unit. The control section displays, on the display section, prediction information related to the completion of a cooling operation to cool the fixing unit mounted in the image forming apparatus on the basis of a result of measurement performed by the temperature measuring section.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to an image forming apparatus and the like. [Background technology]

[0002] Conventionally, a dry electrophotographic method (laser printer method) has been used as a printing method for image forming devices such as printers and multifunction devices. In the laser printer method, after toner is transferred to form an image on paper, the image on the paper is heated and pressurized to fix the image on the paper. For this reason, image forming devices that print using the laser printer method are equipped with a fixing device for heating and pressurizing the image on the paper.

[0003] The fixing unit has a fixing member that comes into contact with the paper on which the image to be fixed is formed. The fixing member is, for example, a fixing belt. The fixing belt is disposed so that its longitudinal direction is perpendicular to the paper transport direction. In this application, the width of the paper in the direction perpendicular to the paper transport direction is called the paper width. For example, in a general MFP (Multi Function Printer) having a scanner function, the sub-scanning direction of the scanner coincides with the paper transport direction, and the main scanning direction of the scanner is perpendicular to the paper transport direction. Therefore, in a general MFP, the paper width refers to the width of the paper in the main scanning direction.

[0004] 26A is a diagram for explaining scratches that occur on the fixing belt when A5 paper passes repeatedly. When A5 paper 301 passes repeatedly through fixing belt 303, scratches 305 and 307 occur on fixing belt 303 at positions corresponding to the paper width of A5 paper 301. After these scratches occur, consider that A3 paper 309, which is larger than A5 paper, passes repeatedly over the same fixing belt 303.

[0005] 26(b), scratches 311, 313 also occur on fixing belt 303 at positions corresponding to the paper width of A3 paper 309, but scratches 311, 313 are almost outside A3 paper 309 and therefore do not affect the print quality of A3 paper 309. However, scratches 305, 307 caused by A5 paper 301 are contained within the paper width of A3 paper 309 and therefore adversely affect the print quality of A3 paper 309. Specifically, stains 315, 317 occur on A3 paper 309 at positions corresponding to scratches 305, 307 caused by A5 paper 301.

[0006] To avoid this problem, it has been considered to use the fixing belt only for printing a specific paper width. That is, as shown in Fig. 27(a), fixing belt 303 is used when printing A5 paper 301, while another fixing belt 321 is used when printing A3 paper 309, as shown in Fig. 27(b). Although scratches 305 and 307 occur on fixing belt 303 and scratches 311 and 313 occur on fixing belt 321 due to repeated printing, since a fixing belt is prepared for each paper width, it is possible to prevent scratches occurring when printing other paper widths from adversely affecting print quality.

[0007] As described above, another operating method for replacing the fixing belt or fixing unit is disclosed in Patent Document 1. The types of media that can be passed through are becoming more diverse, and detailed adjustments of the fixing conditions that determine the final image quality are required depending on the thickness and surface properties of the media, the density and gloss of the desired image product, etc. As a countermeasure against these issues, Patent Document 1 proposes that a dedicated fixing unit be prepared according to the paper size and type of media that can be passed through, and that the user can obtain optimal image quality by replacing the fixing unit as necessary.

[0008] Generally, since a fixing unit becomes hot after operation, when replacing the fixing unit, it is necessary to take this high temperature into consideration and wait for the fixing unit to cool down to a predetermined temperature before replacing it. In relation to this, Patent Document 1 proposes notifying a user whether or not the temperature of the installed fixing unit has cooled down to a predetermined temperature or lower. [Prior art documents] [Patent documents]

[0009] [Patent Document 1] JP 2017-003725 A Summary of the Invention [Problem to be solved by the invention]

[0010] According to Patent Document 1, the user is notified after the temperature drops below a predetermined temperature, but is not notified of the time required for the temperature to drop. Generally, it takes a certain amount of time for a high-temperature fixing unit to drop to a predetermined temperature, but conventional image forming devices do not notify the user of this required time. Therefore, the user must constantly monitor the current temperature of the fixing unit while waiting for the fixing unit to drop. If this monitoring is neglected, the fixing unit that has reached the predetermined temperature may be left unattended, resulting in unnecessary waiting time, which may result in a delay in the entire fixing unit replacement operation.

[0011] The present disclosure has been made in light of the above circumstances, and a problem to be solved by the present disclosure is to improve the efficiency of the time required for replacing a fixing unit. [Means for solving the problem]

[0012] In order to solve the above-mentioned problems, the present disclosure provides an image forming apparatus including a control unit, a display unit, a detachable fixing unit, and a temperature measurement unit that measures the temperature of the fixing unit or its vicinity, and the control unit displays on the display unit predicted information regarding the completion of a cooling operation for cooling the installed fixing unit based on the measurement results by the temperature measurement unit.

[0013] The present disclosure also provides an operating method for an image forming apparatus having a removable fixing unit, the operating method including the steps of measuring the temperature of the fixing unit or its vicinity, and displaying, based on the results of the measurement, predicted information regarding the completion of a cooling operation for cooling the installed fixing unit. Effect of the Invention

[0014] According to the present disclosure, it is possible to improve the efficiency of the time required for replacing a fixing unit. [Brief description of the drawings]

[0015] [Figure 1] 1 is a functional block diagram of an image forming apparatus according to an embodiment of the present invention. [Diagram 2] 4 is a flowchart illustrating an operation of the image forming apparatus according to the embodiment of the present invention. [Diagram 3] 10 is a diagram showing an example of a home screen displayed on a display unit of the image forming apparatus when replacing a fixing unit in the embodiment of the present invention. FIG. [Figure 4] 13 is a diagram showing an example of a machine adjustment screen displayed on a display unit of the image forming apparatus when replacing a fixing unit in an embodiment of the present invention. FIG. [Diagram 5] 11 is a diagram showing an example of an image quality adjustment screen displayed on a display unit of the image forming apparatus when replacing a fixing unit in an embodiment of the present invention. [Figure 6] 13 is a diagram showing an example of an other function screen displayed on a display unit of the image forming apparatus when replacing a fixing unit in the embodiment of the present invention. FIG. [Figure 7] 13 is a diagram showing an example of a fixing unit type display screen displayed on a display unit of the image forming apparatus when replacing a fixing unit in the embodiment of the present invention. FIG. [Figure 8] 13 is a diagram showing an example of a precaution confirmation screen displayed on a display unit of the image forming apparatus when replacing a fixing unit in the embodiment of the present invention. FIG. [Figure 9]13 is a diagram showing an example of a precaution confirmation screen displayed on a display unit of the image forming apparatus when replacing a fixing unit in the embodiment of the present invention. FIG. [Figure 10] 13 is a diagram showing an example of a replacement preparation start screen displayed on a display unit of the image forming apparatus when replacing a fixing unit in an embodiment of the present invention. FIG. [Figure 11] 13 is a diagram showing an example of a fixing unit type designation request screen displayed on a display unit of the image forming apparatus when replacing a fixing unit in an embodiment of the present invention. FIG. [Figure 12] 13 is a diagram showing an example of a replacement confirmation screen displayed on a display unit of the image forming apparatus when replacing a fixing unit in the embodiment of the present invention. FIG. [Figure 13] 13 is a diagram showing an example of a cooling screen displayed on a display unit of the image forming apparatus when replacing a fixing unit in the embodiment of the present invention. FIG. [Figure 14] 13 is a diagram showing an example of a preparation completion screen displayed on a display unit of the image forming apparatus when replacing a fixing unit in the embodiment of the present invention. FIG. [Figure 15] FIG. 13 is a diagram showing an example of a replacement confirmation screen displayed on a display unit of the image forming apparatus when replacing a fixing unit in the first modified example of the embodiment of the present invention. [Figure 16] FIG. 13 is a diagram showing an example of a replacement confirmation screen displayed on a display unit of the image forming apparatus when replacing a fixing unit in the first modified example of the embodiment of the present invention. [Figure 17] FIG. 13 is a diagram showing an example of a cooling screen displayed on a display unit of an image forming apparatus when replacing a fixing unit in a second modified example of the embodiment of the present invention. [Figure 18] FIG. 13 is a diagram showing an example of a cooling screen displayed on a display unit of an image forming apparatus when replacing a fixing unit in a third modified example of the embodiment of the present invention. [Figure 19] FIG. 13 is a diagram showing an example of a replacement confirmation screen displayed on a display unit of an image forming apparatus when replacing a fixing unit in a fourth modified example of the embodiment of the present invention. [Figure 20]FIG. 13 is a diagram showing an example of a cooling screen displayed on a display unit of an image forming apparatus when replacing a fixing unit in a fourth modified example of the embodiment of the present invention. [Figure 21] FIG. 13 is a diagram showing an example of a start time setting screen displayed on a display unit of an image forming apparatus when setting a time to start preparation for replacing a fixing unit in a fifth modified embodiment of the present invention. [Figure 22] FIG. 13 is a diagram showing an example of a screen displayed by another function executable by the image forming apparatus until the start time of preparation for fixing unit replacement is set in the fifth modified embodiment of the present invention. [Diagram 23] FIG. 21 is a diagram showing an example of a start confirmation screen displayed on the display unit of the image forming apparatus when the start time arrives during execution of another function exemplified in FIG. 20 in a fifth modified embodiment of the present invention. [Figure 24] FIG. 13 is a diagram showing an example of a cooling screen displayed on a display unit of an image forming apparatus when replacing a fixing unit in a fifth modified example of the present invention. [Diagram 25] FIG. 23 is a diagram showing an example of a cooling screen displayed on a display unit of an image forming apparatus when replacing a fixing unit in a sixth modified example of the present invention. [Figure 26] Figure 26(a) is a diagram to explain the scratches that occur on the fixing belt when A5 paper passes through, and Figure 26(b) is a diagram to explain the stains that occur on A3 paper when it passes through a fixing belt with scratches. [Figure 27] Figure 27(a) is a diagram for explaining scratches that occur on a fixing belt for A5 paper when A5 paper passes through, and Figure 27(b) is a diagram for explaining scratches that occur on a fixing belt for A3 paper when A3 paper passes through. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] 1. Embodiment 1.1 Functional configuration of image forming device 1 1 is a functional block diagram of an image forming apparatus 1 according to an embodiment of the present invention. The image forming apparatus 1 is an MFP (Multi-Function Printer) or a multifunction machine, and typically includes a copy function, an image scanner function, a facsimile function, and a printer function. The image forming apparatus 1 may further include other functions, such as an email sending / receiving function, a file server function, etc.

[0017] The image forming apparatus 1 includes a display unit 3, an operation unit 5, an image input unit 9, a paper feed unit 11, an image forming unit 13, a communication unit 19, a connection unit 21, a memory unit 23, and a control unit 29. The operation unit 5 includes a main power switch 7. The image forming unit 13 includes a fixing unit 15, a temperature sensor 17, and a cooling unit 18. The memory unit 23 includes an attachment unit type memory unit 25 and a unit type setting information memory unit 27. The control unit 29 includes a cooling time estimation unit 31 and a temperature monitoring unit 33.

[0018] The display unit 3 is a functional unit for displaying images and characters. For example, it is configured with a liquid crystal display (LCD) or an organic EL (Electro-Luminescence) panel. The display unit 3 may be a standalone display device, or may further include an externally connected display device.

[0019] The operation unit 5 accepts operation input from a user. For example, the operation unit 5 is configured with hardware keys and software keys. The operation unit 5 also includes task keys for executing tasks such as fax transmission and image scanning, and a stop key for canceling an operation. The operation unit may also include physical operation keys such as task keys, a stop key, a power key, and a power save key. The main power SW7 is a switch for turning on and off the main power of the image forming apparatus 1.

[0020] The display unit 3 and the operation unit 5 may be integrated together. For example, a touch panel display may be used as the display unit 3 and the operation unit 5.

[0021] The image input unit 9 reads an image (original) and outputs it as image data. The image input unit 9 is configured with a general scanner (image input device). The image input unit 9 may input image data from an external storage medium such as a USB memory, or may receive an image via a network. The sub-scanning direction of the image input unit 9 coincides with the direction in which the paper is transported by the paper feed unit 11.

[0022] Paper feed unit 11 has a paper feed tray that stores media such as paper, and a transport mechanism that transports the media from the paper feed tray to image forming unit 13. Paper feed unit 11 may also have a sorter mechanism that sorts media (paper) on which an image has been formed, a paper output tray for discharging the media on which an image has been formed, and a transport mechanism that transports the media on which an image has been formed to the sorter mechanism or the paper output tray. Paper feed unit 11 may also have a transport mechanism that transports the media on which an image has been formed to image input unit 9, and a transport mechanism that transports the media on which an image has been read by image input unit 9 to the paper output tray, sorter mechanism, etc.

[0023] The paper feed unit 11 transports the medium along the sub-scanning direction of the image input unit 9. In this application, as described above, the width of the paper in the direction perpendicular to the transport direction of the medium (paper) is called the paper width. Therefore, in this embodiment, the paper width can also be called the width of the paper in the main scanning direction of the image input unit 9. The paper feed unit 11 transports the medium such that the longitudinal direction of a fixing belt (not shown) of the fixing unit 15 and the transport direction of the medium are perpendicular to each other.

[0024] The image forming unit 13 forms (prints) an image on a medium such as copy paper based on image data. The printing method of the image forming unit 13 is a laser printer. The image forming unit 13 may be a monochrome laser printer or a color laser printer. The image forming unit 13 may include a paper feed mechanism for supplying the medium, a transport mechanism for transporting the medium, a sorter mechanism for sorting the medium after the image is formed, and the like. The fixing unit 15 is a fixing device that heats and pressurizes the toner image transferred onto the paper, thereby fusing the toner image to the paper. The temperature sensor 17 (temperature measurement unit) is a sensor that measures the temperature of the fixing unit 15. The temperature sensor 17 converts the temperature of the fixing unit 15 into physical quantities such as voltage and resistance value and outputs it.

[0025] The cooling section 18 is a device that performs a cooling operation to cool the fixing unit 15. The cooling section 18 may directly lower the temperature of the fixing unit 15, or may indirectly lower the temperature of the fixing unit 15 by lowering the temperature of the air inside the housing of the image forming apparatus 1. The cooling principle of the cooling section 18 is not particularly limited. For example, it may be air-cooled or water-cooled. It may be a heat pump using a reverse Carnot cycle like an electric refrigerator or air conditioner, or a heat pump using a semiconductor such as a Peltier element. Specifically, the cooling section 18 is, for example, an electric fan that exhausts air inside the housing of the image forming apparatus 1 to the outside of the housing. In FIG. 1, the cooling section 18 is illustrated as a part of the image forming section 13, but it may be provided outside the image forming section 13 as long as it can cool the fixing unit 15. In addition, when the image forming apparatus 1 is operating normally, an electric fan that exhausts air mainly for the purpose of lowering the temperature of the control section 29 may be configured to operate as the cooling section 18 of the fixing unit 15 by operating at a higher speed than usual.

[0026] The communication unit 19 is a functional unit for connecting to a network. The communication unit 19 is configured with an interface that can connect to, for example, a wired LAN (Local Area Network), a wireless LAN, or an LTE (Long Term Evolution) network. When the communication unit 19 is connected to a network, it is connected to other devices and an external network.

[0027] The connection unit 21 connects the image forming apparatus 1 to other devices. For example, the connection unit 21 is a USB interface, and a USB memory or the like is connected to the connection unit 21. The connection unit 21 may also be configured to include a device (e.g., an antenna or the like) for short-range wireless communication such as NFC (Near Field Communication) or Bluetooth (registered trademark).

[0028] Furthermore, the communication unit 19 and the connection unit 21 may be integrated into one unit. For example, they may be provided as a single wireless communication interface, and may be capable of using wireless LAN or Bluetooth.

[0029] The storage unit 23 is a functional unit that stores various programs and various data necessary for the operation of the image forming apparatus 1. The storage unit 23 includes a recording device capable of temporary storage, such as a dynamic random access memory (DRAM), and a non-temporary recording device, such as a solid state drive (SSD) composed of a semiconductor memory and a hard disk drive (HDD) composed of a magnetic disk. Although the storage unit 23 is configured as one unit for convenience of explanation, it may be configured as separate devices for each purpose, such as an area used for executing programs (main storage area), an area for saving programs and data (auxiliary storage area), an area used for caching, etc.

[0030] The attachment unit type storage section 25 stores the type (unit type) of the fixing unit 15 currently attached to the image forming apparatus 1. The unit type corresponds to the type of paper on which an image is fixed using the fixing unit. The paper type is, for example, one of the paper width, the paper material, the thickness, the shape (envelope), and the like, or a combination of these. The paper type based on the paper width is, for example, the long side of the A3 size (420 mm), the short side of the A3 size and the long side of the A4 size (297 mm), the short side of the A4 size and the long side of the A5 size (210 mm), and the like. Similarly, the long side of the B3 size (515 mm), the short side of the B3 size and the long side of the B4 size (364 mm), the short side of the B4 size and the long side of the B5 size (257 mm), and the like.

[0031] The unit type setting information storage unit 27 stores setting information of the image forming apparatus 1 determined for each unit type. The unit type setting information includes, for example, basis weight setting, paper type, paper attribute, fixing temperature setting, fixing pressure setting, primary transfer current value setting, secondary transfer current value setting, and PTC (Pre Transfer Charger) current value setting. The basis weight setting is a setting of the weight per square meter of one sheet of paper. The paper type is a setting of the type of paper, for example, uncoated paper, gloss coated paper, matte course paper, embossed paper, etc. The paper attribute is a setting of the paper attribute, for example, setting whether the paper has a front and back side, whether double-sided printing is not possible, etc. The fixing temperature setting is a setting of the temperature generated by the fixing unit 15 when fixing a toner image. The fixing pressure setting is a setting of the strength of pressure applied by the fixing unit 15 to the paper when fixing a toner image. The primary transfer current value setting is a setting of the magnitude of the current for adhering the toner to the intermediate transfer belt of the fixing unit 15, and is set for each of the colors black (Bk), cyan (C), magenta (M), and yellow (Y). The secondary transfer current value setting is a setting of the magnitude of the current for adhering the toner formed on the intermediate transfer belt to the paper, and is set for each of the front and back sides of the paper. The PTC current value setting is a setting of the magnitude of the current that imparts an electric charge to the toner to be transferred.

[0032] The control unit 29 is a functional unit for controlling the entire image forming apparatus 1. The control unit 29 is composed of one or more control devices and control circuits, and is composed of, for example, a CPU (Central Processing Unit), a SoC (System on a Chip), etc.

[0033] Moreover, the control unit 29 can realize each function by reading out the programs stored in the storage unit 23 and executing the processes.

[0034] The cooling time estimation unit 31 estimates the time required for the temperature of the fixing unit 15 to drop to a level where the fixing unit 15 can be removed from the image forming unit 13, based on the current temperature of the fixing unit 15 measured by the temperature sensor 17.

[0035] The temperature monitoring unit 33 monitors the current temperature of the fixing unit 15 measured by the temperature sensor 17 in real time.

[0036] 1.2 Operation of the Image Forming Apparatus 1 in the Embodiment 2 is a flowchart for explaining the operation of the image forming apparatus 1 when replacing the fixing unit 15. The image forming apparatus 1 can install three types of fixing units (unit types A, B, and C) as fixing units 15 in the image forming section 13. Unit type A is a fixing unit for A4 / A3 sizes. Unit type B is a fixing unit for B5 / B4 sizes. Unit type C is a fixing unit for envelope sizes. Here, an example will be described in which unit type A installed in the image forming section 13 is replaced with unit type B.

[0037] The control unit 29 displays a home screen on the display unit 3 (step S1). Next, the control unit 29 displays a machine adjustment screen on the display unit 3 (step S3). Next, the control unit 29 displays an image quality adjustment screen on the display unit 3 (step S5). Next, the control unit 29 displays an other function screen on the display unit 3 (step S7). Next, the control unit 29 displays a display screen of the fuser type before replacement on the display unit 3 (step S9). Next, the control unit 29 displays a precautions confirmation screen on the display unit 3 (step S11). Next, the control unit 29 displays a replacement preparation start screen on the display unit 3 (step S13). Next, the control unit 29 displays a fuser type designation request screen on the display unit 3 (step S15). Next, the control unit 29 displays a replacement confirmation screen on the display unit 3 to confirm with the user whether or not to start preparation for replacement of the fuser unit (step S17).

[0038] When the replacement confirmation screen receives an input via the operation unit 5 indicating that it is OK to start preparation for replacement (step S19, Yes), the control unit 29 displays on the display unit 3 a cooling screen indicating that it is waiting for the temperature of the currently installed fixing unit 15 to drop to a predetermined value, and starts a cooling operation to cool the fixing unit 15 (step S21).

[0039] In the cooling operation of the fixing unit 15, the control unit 29 stops the power supply to the fixing unit 15. In addition, in the cooling operation, the control unit 29 activates the cooling unit 18 to promote the temperature drop of the fixing unit 15.

[0040] When the cooling operation starts, the temperature monitoring unit 33 of the control unit 29 measures the temperature of the fixing unit 15 or its vicinity using the temperature sensor 17 (step S23). Thereafter, the temperature monitoring unit 33 monitors the temperature of the fixing unit 15 using the temperature sensor 17 until the cooling operation is completed. Based on the measurement result by the temperature sensor 17, the cooling time estimation unit 31 of the control unit 29 generates prediction information regarding the cooling time (step S25). The prediction information is, for example, a required time predicted to be required for the temperature of the fixing unit 15 to drop to a predetermined end temperature. In addition, the prediction information is, for example, a time (scheduled end time) when the fixing unit 15 is predicted to drop to the end temperature. The end temperature is a temperature that is predetermined as a temperature at which a user will not get burned even if he or she touches the fixing unit 15 directly, and is, for example, about 40 degrees.

[0041] Next, the control unit 29 displays the prediction information on the display unit 3 (step S27). At this time, a message indicating that cooling is in progress may also be displayed. By looking at the displayed prediction information, the user can know in advance when the cooling operation will end. Therefore, the user can leave the image forming apparatus 1 until the time suggested by the prediction information. In addition, by returning to the image forming apparatus 1 by the time suggested by the prediction information and continuing the work, the user can remove the currently mounted fixing unit 15 from the image forming section 13 without delay and install another fixing unit after the currently mounted fixing unit 15 reaches a temperature at which it can be replaced. As a result, the time required for the entire replacement work of the fixing unit 15, including the cooling operation, can be minimized.

[0042] Next, when the temperature monitored by the temperature monitoring section 33 reaches the end temperature, the control section 29 ends the cooling operation (step S29) and displays a preparation completion screen on the display section 3 (step S31). By visually checking the preparation completion screen, the user can confirm that the fixing unit 15 has actually reached the end temperature.

[0043] 1.3 Example of a screen of the image forming apparatus 1 according to the embodiment A description will be given of an example of a screen displayed on the display unit 3 when replacing the fixing unit 15. Here, it is assumed that the display unit 3 and the operation unit 5 are integrally configured as a touch panel display.

[0044] 3 is a diagram showing an example of a home screen displayed on the display unit 3 of the image forming apparatus 1 when replacing the fixing unit 15 in the embodiment of the present invention. The home screen 51 is a screen that the control unit 29 displays on the display unit 3 after the main power of the image forming apparatus 1 is turned on from a main power off state. The home screen 51 includes a machine adjustment button 53. The control unit 29 displays the home screen 51 on the display unit 3, for example, in step S1. When the user touches the machine adjustment button 53, the control unit 29 displays a machine adjustment screen 55, which will be described next.

[0045] 4 is a diagram showing an example of a machine adjustment screen displayed on the display unit 3 of the image forming apparatus 1 when replacing the fixing unit 15 in the embodiment of the present invention. In step S1, when the home screen 51 is displayed on the display unit 3 and the user touches the machine adjustment button 53, the control unit 29 proceeds to step S3 and displays the machine adjustment screen 55 on the display unit 3. The machine adjustment screen 55 is a menu screen related to various adjustment operations of the image forming apparatus 1. The machine adjustment screen 55 includes an image quality adjustment button 57. The image quality adjustment button 57 is an area that is touched when proceeding to the image quality adjustment screen, which will be described next.

[0046] 5 is a diagram showing an example of an image quality adjustment screen displayed on the display unit 3 of the image forming apparatus 1 when replacing the fixing unit 15 in the embodiment of the present invention. In step S3, when the machine adjustment screen 55 is displayed on the display unit 3, if the user touches the image quality adjustment button 57, the control unit 29 proceeds to step S5 and displays the image quality adjustment screen 61 on the display unit 3. The image quality adjustment screen 61 is a menu screen related to adjusting the image quality of the image formed on paper by the image forming unit 13. The image quality adjustment screen 61 includes an other function button 63. The other function button 63 is an area that is touched when proceeding to the other function screen 67 described next.

[0047] 6 is a diagram showing an example of an other function screen displayed on the display unit 3 of the image forming apparatus 1 when replacing the fixing unit 15 in the embodiment of the present invention. In step S5, when the image quality adjustment screen 61 is displayed on the display unit 3, if the user touches the other function button 63, the control unit 29 proceeds to step S7 and displays the other function screen 67 on the display unit 3. The other function screen 67 is a menu screen related to image quality adjustment of the image formed on the paper by the image forming unit 13. The other function screen 67 includes a fixing unit replacement button 69. The fixing unit replacement button 69 is an area that is touched when proceeding to the fixing unit type display screen 73 described next.

[0048] 7 is a diagram showing an example of a fuser type display screen displayed on the display unit 3 of the image forming apparatus 1 when replacing the fuser unit 15 in the embodiment of the present invention. In step S7, when the other function screen 67 is displayed on the display unit 3, if the user touches the fuser unit replacement button 69, the control unit 29 proceeds to step S9 and displays the fuser type display screen 73 on the display unit 3.

[0049] The fuser type display screen 73 is a screen that displays the unit type of the fuser unit 15 currently installed in the image forming apparatus 1. The fuser type display screen 73 includes a unit type list 75. The unit type list 75 displays unit types A 75a, B 75b, and C 75c.

[0050] Of these unit types, the control unit 29 displays (for example, inverts or highlights) the unit type of the currently attached fixing unit 15 in a selected state on the display unit 3 based on the unit type stored in the attachment unit type storage unit 25. As described above, the fixing unit 15 currently attached to the image forming apparatus 1 is unit type A, so unit type A 75a is displayed in a selected state. The unit type stored in the attachment unit type storage unit 25 is registered via the operation unit 5, for example, when the user performs initial settings of the image forming apparatus 1. Thereafter, the unit type stored in the attachment unit type storage unit 25 is updated by the unit type designated on the fixing unit type designation request screen in step S11, which will be described later.

[0051] In this way, by displaying the unit type of the currently installed fixing unit 15, the user can easily recognize the unit type of the currently installed fixing unit 15. This also makes it possible to prevent the user from accidentally replacing the fixing unit 15 with a fixing unit of a different unit type.

[0052] If it is determined at this time that there is no need to change the unit type of the fixing unit 15, the user can cancel the replacement of the fixing unit by touching the back button 79. If the user still wants to replace the fixing unit after this confirmation, the user touches the next button 77. When the next button 77 is touched, the control unit 29 proceeds to step S7.

[0053] 8 is a diagram showing an example of a precautions confirmation screen displayed on the display unit 3 of the image forming apparatus 1 when replacing the fixing unit 15 in the embodiment of the present invention. In step S9, when the fixing unit type display screen 73 is displayed on the display unit 3, if the user touches the next button 77, the control unit 29 proceeds to step S10 and displays a precautions confirmation screen 80 on the display unit 3.

[0054] The precaution confirmation screen 80 is a screen for informing a user who is to replace the fixing unit 15 of various precautions regarding the replacement work before the replacement work and for requesting the user to confirm that the precautions have been conveyed to the user. The precaution confirmation screen 80 includes a precaution display field 80a, a declaration display field 80b, a check field 80c, a back button 80d, a next button 80e, and a scroll bar 80f.

[0055] The caution display field 80a displays a message addressed to the user who will perform the replacement work. The message in the caution display field 80a may be a list of cautions regarding the replacement work. In addition to or instead of such a message, the message in the caution display field 80a may inform the user who will perform the replacement work that there is a risk of injury or burns in the replacement work. Note that the caution display field 80a does not need to display the entire message at once. The message displayed in the caution display field 80a is scrolled up and down in response to the operation of the scroll bar 80f via the operation unit 5. In the caution display field 80a, the entire message can be viewed by scrolling.

[0056] The declaration display field 80b contains a message for the user performing the replacement work to declare that, prior to the replacement work, they have received sufficient training on the appropriate handling method for the fixing unit, and that they understand the risks associated with the replacement work. If the user agrees with the message in the declaration display field 80b, he or she checks the check field 80c via the operation unit 5. On the precautions confirmation screen 80, the check field 80c is not checked. When the check field 80c is not checked, the Next button 80e is displayed in gray. The grayed-out display indicates that the Next button 80e is currently not selectable.

[0057] The scroll bar 80f includes an up arrow button 80g, a down arrow button 80h, and a knob 80i. The scroll bar 80f is operated by the user via the operation unit 5 to scroll the message displayed in the notice display field 80a. When the up arrow button 80g is touched via the operation unit 5, the message displayed in the notice display field 80a is scrolled upward. Similarly, when the down arrow button 80h is touched, the message is scrolled downward. Instead of touching the up arrow button 80g or the down arrow button 80h, the message displayed in the notice display field 80a may be scrolled up and down by touching and moving the knob 80i up and down via the operation unit 5.

[0058] When an operation to check the check box 80c is performed via the operation unit 5 on the precaution confirmation screen 80, the control unit 29 shifts the screen displayed on the display unit 3 from the precaution confirmation screen 80 to a precaution confirmation screen 80-2 illustrated in FIG. 9. FIG. 9 is another example of a precaution confirmation screen displayed on the display unit 3 of the image forming apparatus 1 when replacing the fixing unit 15 in the embodiment of the present invention. The check box 80c, which was blank on the precaution confirmation screen 80, is checked, and the check box 80c-2 on the precaution confirmation screen 80-2 is changed to a checked check box 80c-2. In response to the checked check box 80c-2, the Next button 80e, which was grayed out on the precaution confirmation screen 80, shifts to a normal display state like the Next button 80e-2 on the precaution confirmation screen 80-2, indicating that it is selectable.

[0059] 10 is a diagram showing an example of a replacement preparation start screen displayed on the display unit 3 of the image forming apparatus 1 when replacing the fixing unit in the embodiment of the present invention. In step S13, the control unit 29 displays a replacement preparation start screen 81 on the display unit 3. The replacement preparation start screen 81 includes messages 83, 85, 87, a back button 89, a two-dimensional barcode 91, and a next button 93.

[0060] A message 83 is a message for notifying the user that preparations are required prior to replacing the fixing unit. The preparations include the cooling operation described above.

[0061] Message 85 is a message for informing the user that the fixing unit may be at a high temperature. In particular, immediately after image forming apparatus 1 outputs a medium on which an image is formed, the fixing member of fixing unit 15 is at a high temperature (for example, 160 to 180 degrees). Message 85 alerts the user not to directly touch fixing unit 15 at such a high temperature.

[0062] Message 87 notifies the user of information for accessing the procedure manual for replacement work. Message 87 describes address information for data of the procedure manual that can be downloaded by a device other than image forming apparatus 1. Specifically, a device other than image forming apparatus 1 is, for example, a smartphone, tablet, personal computer, etc. (hereinafter, referred to as a user terminal) of a user who replaces the fixing unit. By performing the work while reading the procedure manual on the user terminal, even a user who has no knowledge of fixing units or replacement procedures can safely perform the replacement work.

[0063] Usually, the display unit 3 of the image forming device 1 displays the current status of the image forming device 1, commands that can currently be instructed or set for the image forming device 1, various numerical values, etc. Since the display size of the display unit 3 is limited, it is difficult to simultaneously display these items and the instruction manual. It is possible to switch between these displays and the instruction manual as necessary, but in this case, the operation is likely to become complicated. By displaying the instruction manual on the user terminal, such problems can be avoided.

[0064] As described later, the work of replacing the fixing unit includes the process of turning on and off the main power supply of the image forming apparatus 1. Therefore, if the instruction manual is displayed on the display unit 3 of the image forming apparatus 1, there will be a period during the work when the instruction manual cannot be checked. However, a user who reads the message 87 can download the instruction manual to the user terminal, and therefore can check the instruction manual regardless of whether the power supply of the image forming apparatus 1 is on or off.

[0065] In the message 87, a URL (Uniform Resource Locator) on the Internet is described as address information, but the address information described here is not limited to address information of a resource on the Internet, and may be address information of a resource that can be accessed from a user terminal and from which data of a procedure manual can be downloaded. For example, when both the user terminal and the image forming apparatus 1 can be connected to the same LAN (Local Area Network), the procedure manual may be stored in the storage unit 23 of the image forming apparatus 1, and the control unit 29 may operate as a file server to provide data of the procedure manual to the user terminal via the LAN. In addition, a Bluetooth communication function may be provided in the communication unit 19 and / or the connection unit 21, and a file may be shared with a user terminal that also has a Bluetooth communication function, so that the user terminal may download the procedure manual data from the image forming apparatus 1 via the Bluetooth communication function.

[0066] Instead of displaying the instruction manual on the user terminal, the instruction manual may be displayed on the display unit 3 of the image forming apparatus 1. In this case, as described above, although the instruction manual cannot be checked while the main power supply of the image forming apparatus 1 is being turned on and off, there is no need to prepare a separate user terminal.

[0067] The two-dimensional barcode 91 is a two-dimensional barcode that displays the address information of the instruction manual data. The address information indicated by the two-dimensional barcode 91 may be the same address as the address information written in the message 87 or a different address.

[0068] When the user touches the back button 89, the control unit 29 displays the fixing unit type display screen 73 on the display unit 3. When the user touches the next button 93, the control unit 29 proceeds to the next step S15.

[0069] 11 is a diagram showing an example of a fuser type designation request screen displayed on the display unit 3 of the image forming apparatus 1 when replacing the fuser unit 15 in the embodiment of the present invention. The fuser type designation request screen 103 is in a state after the user touches and selects unit type B 107b. Therefore, unit type B 107b is displayed in a selected state on the fuser type designation request screen 103.

[0070] When the user touches the Next button 111 on the fuser type designation request screen 103, the control unit 29 proceeds to the next step S17 assuming that the unit type currently in the selected state, i.e., unit type B, has been selected. Also, at this time, the control unit 29 updates the unit type stored in the attachment unit type storage unit 25 with the selected unit type. When the Next button 111 is touched on the fuser type designation request screen 103, the control unit 29 updates the unit type stored in the attachment unit type storage unit 25 to unit type B.

[0071] By requesting the user to input the unit type of the replaced fixing unit, as in the fixing unit type designation request screen 103, it is possible to prevent the user from replacing the fixing unit with a different unit type by mistake.

[0072] 12 is a diagram showing an example of a replacement confirmation screen displayed on the display unit 3 of the image forming apparatus 1 when replacing the fixing unit 15 in the embodiment of the present invention. The replacement confirmation screen 113 has a message area 115. In the message area 115, a message 115a is displayed to confirm to the user that preparation for replacing the fixing unit 15 is to be started. The message area 115 also has an OK button 115b and a cancel button 115c. If the OK button 115b is touched (step S19, Yes), the control unit 29 proceeds to step S21 and starts the cooling operation. If the cancel button 115c is touched (step S19, No), the control unit 29 stops (ends) the process.

[0073] 13 is a diagram showing an example of a cooling screen displayed on the display unit 3 of the image forming apparatus 1 when replacing the fixing unit 15 in the embodiment of the present invention. In step S21, the control unit 29 starts the cooling operation, and also measures the temperature of the fixing unit 15 with the temperature sensor 17 by the temperature monitoring unit 33 (step S23), generates prediction information based on the measurement result (step S25), and displays the cooling screen 121 on the display unit 3 (step S27).

[0074] The cooling screen 121 includes a message area 123. In the message area 123, a message 123a instructing the user to wait until the temperature of the fixing unit 15 drops, prediction information 123b, and a stop button 125 are displayed.

[0075] The prediction information 123b includes the required time and the scheduled end time. The time "60 minutes" listed as the required time is a value calculated by the cooling time estimation unit 31 of the control unit 29 based on the current temperature of the fixing unit 15 measured by the temperature sensor 17. The time "11:52" listed as the scheduled end time indicates the time after the required time has elapsed from the current time. By looking at the required time, the user can know how long the cooling operation will take. Also, by looking at the scheduled end time, the user can know when the user can start replacing the fixing unit after the cooling operation is completed.

[0076] Even after step S23, temperature monitoring section 33 periodically measures the temperature of fixing unit 15 using temperature sensor 17 and compares it with the end temperature. If the temperature of fixing unit 15 reaches or exceeds the end temperature without touching stop button 125, control section 29 ends the cooling operation (step S29) and proceeds to step S31.

[0077] 14 is a diagram showing an example of a preparation completion screen displayed on the display unit 3 of the image forming apparatus 1 when replacing the fixing unit 15 in the embodiment of the present invention. The control unit 29 displays the preparation completion screen 145 in step S31. The preparation completion screen 145 includes messages 147, 85, 87, a cancel button 151, a two-dimensional barcode 91, and a replacement start button 153.

[0078] Message 147 includes a message notifying the user that the temperature of fixing unit 15 has reached the end temperature and it is now ready to perform replacement work. Message 147 also includes a message notifying the user that touching replacement start button 153 will turn off the power to the operation panel (display unit 3 and operation unit 5) and transition image forming apparatus 1 to a standby state. Message 147 also includes a message instructing the user to turn off main power switch 7 to power off image forming apparatus 1 after image forming apparatus 1 transitions to the standby state.

[0079] The cancel button 151 is a button for instructing the image forming apparatus 1 to cancel the replacement of the fixing unit 15.

[0080] The replacement start button 153 is a button for finally instructing the image forming apparatus 1 to replace the fixing unit 15. The messages 85, 87 and the two-dimensional barcode 91 have already been described with reference to FIG.

[0081] When preparation complete screen 145 is displayed and replacement start button 153 is touched, the power to the operation panel is turned off. Thereafter, the user turns off main power switch 7 of image forming apparatus 1, removes fixing unit 15, which is unit type A, from image forming section 13, and attaches fixing unit 15, which is unit type B, to image forming section 13. After attachment, turning on main power switch 7 enables image formation using fixing unit 15, which is unit type B.

[0082] 1.4 Effects of the embodiment The embodiment has the following advantages.

[0083] In step S9, the fixing unit type display screen 73 is displayed, so that the user can check the unit type of the fixing unit 15 currently installed before replacing it.

[0084] In step S15, the fixing unit type designation request screen 103 is displayed to request the user to input the unit type, so that the user can be urged to reliably recognize the unit type after replacement, and this can prevent the fixing unit 15 from being replaced with an incorrect unit type.

[0085] In step S13, the user is notified of information for accessing the replacement procedure manual as a message 87 on the replacement preparation start screen 81, so that the user can replace the fixing unit 15 while looking at the user terminal. Therefore, even a user who lacks knowledge about the structure of the image forming apparatus 1 or the details of the replacement procedure of the fixing unit 15 can safely perform the replacement procedure. In addition, since the procedure manual can be viewed on the user terminal, the user can view the procedure manual regardless of whether the power of the image forming apparatus 1 is on or off.

[0086] In step S27, the time required until the cooling operation for cooling the fixing unit 15 is completed and the estimated end time are displayed. The user can see this and know the time when the cooling operation will be completed and the fixing unit will be accessible. Therefore, after the cooling operation starts, the user can leave the image forming apparatus 1 to perform another task or the like until the estimated end time. Also, if the user returns to the image forming apparatus 1 before the estimated end time, the user can remove the installed fixing unit 15 from the image forming section 13 and replace it with another fixing unit without delay after the cooling operation is completed.

[0087] 1.5 Modifications of the embodiment 1.5.1 Variation 1 In the above embodiment, the prediction information generated in steps S21-S25 together with the start of the cooling operation is displayed without being updated until the cooling operation is ended in step S29.

[0088] In this modification, after the replacement confirmation screen 113 is displayed, the scheduled end time is updated as time passes. For example, after the replacement confirmation screen 113 in FIG. 15 is displayed immediately after the start of the cooling operation, the temperature monitoring unit 33 measures the temperature of the fixing unit 15 every minute, generates a scheduled end time, and updates the value of the scheduled end time on the replacement confirmation screen 113. FIG. 16 shows the replacement confirmation screen 113 that is displayed five minutes after the replacement confirmation screen 113 in FIG. 15 is displayed. As can be seen by comparing the scheduled end times with each other, the scheduled end time "15:45" in FIG. 16 has been updated to five minutes after the scheduled end time "15:40" in FIG. 15. According to this modification, a more accurate estimated end time can be displayed.

[0089] 1.5.2 Transformation 2 In this modification, the cooling screen 121 in FIG. 13 displayed in step S27 is replaced with the cooling screen 121 in FIG. 17. In FIG. 13, the prediction information 123b is displayed as text information in the message area 123. In contrast to this, in this modification, the prediction information is displayed in the form of a graph, as in the progress bar 123c in FIG. 17. That is, the control unit 29 calculates the required time in the same manner as in the above embodiment, and then periodically calculates the progress of the cooling operation and displays it on the display unit 3 as the progress bar 123c. The progress is calculated by finding the time elapsed since the start of the cooling operation, and calculating the ratio of the elapsed time to the required time as a percentage. According to this modification, the progress of the cooling operation can be displayed almost in real time.

[0090] 1.5.3 Transformation 3 In this modification, when the required time changes due to a change in the environmental conditions, the prediction information on the cooling screen is updated. The environmental conditions are conditions regarding the environment in which the image forming device 1 is placed, and in particular the temperature around the image forming device 1. In the above embodiment, the prediction information is generated on the assumption that the image forming device 1 is operated in a general office environment. Therefore, if the image forming device 1 is installed in an extremely hot or cold place, the prediction information may deviate from the actual progress. Also, opening the cover of the image forming device 1 to blow cool air into it shortens the time it takes to complete cooling.

[0091] When the cooling section 18 has a simple configuration, for example when using only an exhaust fan whose main purpose is to simply exhaust the air inside the housing of the image forming apparatus 1, the fixing unit 15 will have to wait for its temperature to drop naturally due to heat dissipation to the surroundings. At this time, the time required for the temperature of the fixing unit 15 to drop to the end temperature is affected by the temperature difference between the surrounding temperature of the image forming apparatus 1 and the temperature of the fixing unit 15.

[0092] Therefore, when generating the prediction information in step S25, the temperature monitoring unit 33 calculates a predicted temperature of the fixing unit 15 at a predetermined elapsed time (for example, every minute after the start of the cooling operation) in addition to the above-mentioned prediction information, and stores it in the memory unit 23. During the cooling operation, the temperature monitoring unit 33 measures the temperature of the fixing unit 15 using the temperature sensor 17 at every predetermined elapsed time, and obtains the difference between the measured temperature and the predicted temperature at that time stored in the memory unit 23. The obtained difference is compared with a threshold value, and if the difference exceeds the threshold value, the temperature monitoring unit 33 executes steps S25 and S27 again to update the prediction information.

[0093] In this variation, the cooling in progress screen 121 in Fig. 11 is displayed immediately after the start of the cooling operation, and then, after time has passed and environmental conditions have changed, both the required time and the estimated end time are updated. An example of the cooling in progress screen 121 after the update is shown in Fig. 18. Compared to the prediction information 123b in Fig. 13, in the prediction information 123d in Fig. 18, the required time has been shortened by 15 minutes, from 60 minutes to 45 minutes. Accordingly, the estimated end time has been changed from 11:52 to 11:37, also shortened by 15 minutes. According to this modification, the prediction information can be updated in response to changes in the environmental conditions.

[0094] 1.5.4 Variation 4 In this modification, before the start of the cooling operation, the replacement confirmation screen 113 in Fig. 19 is displayed instead of the replacement confirmation screen 113 in Fig. 12. The required time and the scheduled start time are displayed on the replacement confirmation screen 113 in Fig. 19.

[0095] In this modification, after the cooling operation starts, the cooling screen 121 in Fig. 20 is displayed instead of the cooling screen 121 in Fig. 13. The required time and the scheduled end time are displayed on the cooling screen 121 in Fig. 20.

[0096] The current time is used as the scheduled start time. It is preferable that the scheduled start time is updated in real time. The scheduled end time is calculated based on the time when the OK button 115b is touched on the exchange confirmation screen 113 in FIG. 19, and therefore cannot be calculated before the OK button 115b is touched. By displaying the current time as in FIG. 19, it is possible to provide the user with supplementary information regarding the scheduled end time even before the OK button 115b is touched.

[0097] 1.5.5 Transformation 5 In this modification, a start time for the replacement work is set in the image forming apparatus 1, and the image forming apparatus 1 transitions to a cooling operation after the set start time.

[0098] In step S13 of the above embodiment, the start time setting screen 401 of Fig. 21 is displayed instead of the exchange confirmation screen 113 of Fig. 12. If the OK button 407 is touched with the check box 405 unchecked, step S19 and subsequent steps are executed in the same manner as in the embodiment.

[0099] When the OK button 407 is touched with the check box 405 checked, it is set in the image forming apparatus 1 that the replacement work of the fixing unit 15 will start at the start time set in the time setting 403. After that, the user can perform work other than the replacement work in the image forming apparatus 1 until the start time is reached. A screen 411 in FIG. 22 is an example of a screen related to functions that can be performed in the image forming apparatus 1 after the start time is set until the start time. When the set start time is reached, a message area 415 is displayed overlapping on a screen 413 related to the function being used by the user, as shown in FIG. 23. A message is displayed in the message area 415 to inform the user that the replacement work of the fixing unit is scheduled and that the functions of the image forming apparatus 1 cannot be used during the preparation work.

[0100] When the start button 415a on the screen 413 of Fig. 23 is touched, the cooling operation is started and the cooling in progress screen 121 as shown in Fig. 24 is displayed. Thereafter, the process proceeds to steps S29 and S31 as in the embodiment. When the cancel button 415b on the screen 413 of Fig. 23 is touched, the set replacement operation is cancelled.

[0101] According to this modification, the user can make a reservation in the image forming apparatus 1 for the replacement work of the fixing unit.

[0102] 1.5.6 Variation 6 In the above embodiment, the cooling screen 121 in Fig. 13 is displayed in step S27. In this modification, instead of the cooling screen 121 in Fig. 13, the cooling screen 121 in Fig. 25 is displayed.

[0103] Compared to the cooling screen 121 of Fig. 13, the cooling screen 121 of Fig. 25 displays prediction information 123g instead of prediction information 123b. The prediction information 123g differs from the prediction information 123b in that it includes the current time.

[0104] The current time included in the prediction information 123g is the current time indicated by a clock that is referenced when the image forming apparatus 1 generates time information. This current time may be generated by a circuit included in the image forming apparatus 1 itself, or may be time information obtained from an NTP server using, for example, the Network Time Protocol (NTP).

[0105] By displaying the current time based on the time information of the image forming apparatus 1 as the predicted information 123g, the user can know the difference between the time of the clock he or she carries (e.g., a wristwatch, a smartphone, etc.) and the time used as a reference by the image forming apparatus 1. Therefore, even if there is a difference between the time referred to by the image forming apparatus 1 and the time referred to by the user, the user can know the exact time when the cooling operation will end.

[0106] 1.5.8 Other Transformations The present disclosure is not limited to the above-described embodiments and modifications, and various modifications are possible. In other words, the technical scope of the present disclosure also includes embodiments obtained by combining technical means that are appropriately modified within the scope of the gist of the present disclosure.

[0107] The programs that run on each device in the embodiments are programs that control the CPU and the like (programs that make a computer function) so as to realize the functions of the above-described embodiments. Information handled by these devices is temporarily stored in a temporary storage device (e.g., RAM) during processing, and is then stored in various storage devices such as ROMs (Read Only Memories) and HDDs, and is read, modified, and written by the CPU as necessary.

[0108] Here, the recording medium for storing the program may be any of semiconductor media (e.g., ROM, non-volatile memory cards, etc.), optical recording media, magneto-optical recording media (e.g., DVD (Digital Versatile Disc), MO (Magneto Optical Disc), MD (Mini Disc), CD (Compact Disc), BD (Blu-ray (registered trademark) Disc), etc.), magnetic recording media (e.g., magnetic tape, flexible disk, etc.), etc. Furthermore, not only are the functions of the above-mentioned embodiments realized by executing the loaded program, but the functions of the present disclosure may also be realized by processing in cooperation with an operating system or other application programs, etc., based on instructions from the program.

[0109] In addition, when distributing the program on the market, the program can be stored in a portable recording medium and distributed, or transferred to a server computer connected via a network such as the Internet. In this case, the storage device of the server computer is of course included in the present disclosure. [Explanation of symbols]

[0110] 1. Image forming device 3 Display section 5 Control section 7 Main power switch (SW) 9. Image Input Section 11 Paper feed section 13 Image forming section 15 Fuser unit (fuser) 17 Temperature Sensor 18 Cooling section 19 Communications Department 21 Connection 23 Memory section 25 Attachment unit type memory section 27 Unit type setting information storage section 29 Control Unit 31 Cooling time estimation part 33 Temperature monitoring section 51 Home Screen 53 Machine adjustment button 55 Machine adjustment screen 57 Picture quality adjustment button 59, 65, 71, 79, 80d, 89, 109, 117, 127 Back button 61 Image quality adjustment screen 63 Other function buttons 67 Other function screen 69 Fuser unit replacement button 73 Fuser type display screen 75, 105 Unit Type List 75a, 105a Unit Type A 75b, 105b Unit Type B 75c, 105c Unit Type C 77, 80e, 80e-2, 93, 111, 119, 131 Next button 80, 80-2 Notes confirmation screen 80a Notes display field 80b Oath display field 80c, 80c-2, 405 Check column 80f Scrollbar 80g Upper Arrow Button 80h Down Arrow Button 80i knob 81 Exchange preparation start screen 83, 85, 87, 115a, 115d, 147 Messages 91 2D Barcode 103 Fixing unit type selection request screen 113 Exchange confirmation screen 115, 123, 415 message area 121 Cooling screen 125 Stop button 151, 415b Cancel button 407 OK button 145 Ready screen 153 Exchange start button 301 A5 Paper 303, 321 Fixing belt 305, 307, 311, 313 Scratches 309 A3 Paper 315, 317 Dirt 401 Start time setting screen 403 Time setting 411, 413 screen 415a Start button

Claims

1. The device includes a control unit, a display unit, a detachable fixing unit, and a temperature measuring unit that measures a temperature of the fixing unit or a temperature in the vicinity of the fixing unit, the control unit displays, on the display unit, predicted information regarding the completion of a cooling operation for cooling the fixing unit that is currently installed, based on a measurement result by the temperature measurement unit. Image forming device.

2. The image forming apparatus according to claim 1 , wherein the prediction information includes a time required for the currently installed fixing unit to cool down to a predetermined temperature.

3. 3. The image forming apparatus according to claim 1, wherein the prediction information includes a scheduled end time that is predicted as a time at which the installed fixing unit will drop in temperature to a predetermined temperature.

4. The control unit repeatedly performs measurement by the temperature measurement unit, and displays the prediction information updated according to the measurement result on the display unit.

3. The image forming apparatus according to claim 1 or 2.

5. The control unit displays the prediction information on the display unit before starting the cooling operation.

3. The image forming apparatus according to claim 1 or 2.

6. The control unit displays, before the start of the cooling operation, a current time or a scheduled start time, which is a time to start the cooling operation, together with the prediction information on the display unit. The image forming apparatus according to claim 5 .

7. the control unit displays, on the display unit, a scheduled end time that is predicted as a time when the temperature of the installed fixing unit will drop to a predetermined temperature after the start of the cooling operation.

7. The image forming apparatus according to claim 6.

8. the control unit, before starting the cooling operation, displays the prediction information on the display unit, and displays on the display unit an input screen for receiving input of a scheduled start time, which is a time when the cooling operation is scheduled to be started. The image forming apparatus according to claim 5 .

9. The control unit further displays the current time on the display unit.

3. The image forming apparatus according to claim 1 or 2.

10. The image forming apparatus according to claim 1 , wherein the control unit displays, on the display unit, a graph indicating a progress of the cooling operation based on the prediction information and a current time.

11. A method for operating an image forming apparatus having a removable fixing unit, comprising: measuring a temperature at or near the fusing unit; displaying prediction information regarding the completion of a cooling operation for cooling the currently installed fixing unit based on the results of the measurement; A method of operating an image forming apparatus comprising:

Images