Image forming apparatus, sheet type setting method, and sheet type setting program

Abstract

To provide an image forming apparatus, a sheet type setting method, and a sheet type setting program for preventing unnecessary switching of sheet type setting modes without impairing the effect of an automatic reset function, thereby allowing smooth execution of image forming processing.SOLUTION: An image forming apparatus 1 receives a print job and starts the execution of the job, and if subsequently a reason for interruption such as paper empty arises, interrupts the execution of the print job. When an automatic reset time elapses with the image forming apparatus remaining in the interruption state, the apparatus checks a sheet type setting mode, and if the mode is a user designation mode, inhibits the sheet type setting mode from being switched to a default setting by an automatic reset function. Subsequently, the image forming apparatus resumes the execution of the print job while maintaining the sheet type setting mode to the user designation mode. When the automatic reset time elapses after the completion of the print job, the image forming apparatus returns the sheet type setting mode to the default setting.SELECTED DRAWING: Figure 8

Description

[Technical Field]

[0001] The present disclosure relates to an image forming apparatus, a sheet type setting method, and a sheet type setting program, and more particularly to a technique for appropriately setting the type of recording sheet used in image forming processing. [Background technology]

[0002] In recent years, user needs for electrophotographic image forming devices have become increasingly diverse, one example of which is the diversification of recording sheets. Users now desire to use a wide variety of recording sheets for image formation processes, including not only plain paper but also thick paper such as postcards and envelopes with overlapping sheets. This has created a demand for image forming devices that can form high-quality images on a variety of recording sheets.

[0003] Since the image process conditions for forming high-quality images differ depending on the type of recording sheet, in order to form high-quality images on a variety of recording sheets, it is necessary to set the image process conditions according to the characteristics of the recording sheet. For this reason, image forming devices are equipped with an operation panel (GUI: Graphical User Interface) that allows the user to specify the type of recording sheet.

[0004] However, specifying the type of recording sheet using a GUI is cumbersome and time-consuming for users of image forming devices, and is therefore not necessarily preferred. In particular, for users who do not have sufficient knowledge about recording sheets and image forming devices, it is not necessarily easy to properly specify the type of recording sheet. If the type of recording sheet specified by the user does not match the type of recording sheet contained in the paper feed cassette, the image process conditions cannot be set appropriately, making it impossible to form high-quality images (see, for example, Patent Document 1).

[0005] To address this issue, a technology has been developed that uses a sensor to detect the thickness and quality of the recording sheet fed from the paper cassette of the image forming device, thereby determining the type of recording sheet and setting the image processing conditions. By adopting this technology, appropriate image processing conditions can be automatically set without any user intervention. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2007-62963 Summary of the Invention [Problem to be solved by the invention]

[0007] By providing an automatic detection mode that uses the above-mentioned sensor to detect the type of recording sheet, the image forming apparatus can reduce the hassle of the user having to set the sheet type of the recording sheet via a GUI. However, there are recording sheets that do not meet specifications and are difficult to correctly detect using the above-mentioned sensor. To accommodate such sheets, the image forming apparatus also has, in addition to the above-mentioned automatic detection mode, a setting mode (hereinafter referred to as a "user-specified mode") in which the sheet type of the recording sheet can be set via a GUI or the like.

[0008] In general, image forming apparatuses are often shared by multiple users, and among these users there are experienced users who are familiar with the types of recording sheets and how to specify them, and beginners who are not very knowledgeable.

[0009] Inexperienced users often perform image formation processes without checking the sheet type setting mode, for example. Therefore, if they perform image formation processes assuming the automatic detection mode without realizing that the recording sheet type has been specified in the user-specified mode, the image processing conditions cannot be set properly because the recording sheet type has not been correctly specified, which can result in poor print results, such as reduced image quality. While the example described above is for an inexperienced user, the problem of not realizing that the intended mode is different can also occur even with experienced users.

[0010] To address this issue, it is conceivable to switch the sheet type setting mode to the automatic detection mode after a predetermined time has elapsed after performing image formation processing using a recording sheet of the sheet type set in the user specification mode (hereinafter referred to as "auto reset"). If the auto reset function is provided, even if the sheet type is set in the user specification mode, it will then switch to the automatic detection mode without any user operation, thereby solving the problem of reduced image quality due to an incorrect specification of the recording sheet type.

[0011] However, the auto-reset function may have the following problem: For example, if a paper empty state is detected during image formation and the image formation process is interrupted, it is necessary to pull out the empty paper feed cassette from the image forming apparatus and replenish the paper feed cassette with recording sheets.

[0012] If the task of replenishing recording sheets takes time, the image formation process may be interrupted for a long period of time, and after a certain period of time has passed, the auto-reset function may switch the sheet type setting mode to the automatic detection mode, which is the default setting for the sheet type setting mode.

[0013] As a result, if the automatically detected sheet type differs from the sheet type specified in the print job when the image formation process is resumed, the image formation process may be stopped due to a paper mismatch. If the image formation process cannot be smoothly executed in this way, user convenience will be reduced.

[0014] In response to this, it is conceivable to delay the timing of starting the auto-reset function so that the sheet type setting mode is not automatically reset to the default setting while the image forming process is suspended.

[0015] However, if the timing of starting the auto-reset function is delayed too much, the next user may not realize that the type of recording sheet has been specified in the user-specified mode before the auto-reset function is started, and may execute the image forming process assuming that it is in the automatic detection mode. This makes it more likely that the above-mentioned problem will occur, and the original purpose of the auto-reset function will not be fully achieved.

[0016] The present disclosure has been made in consideration of the above-mentioned problems, and aims to provide an image forming apparatus, a sheet type setting method, and a sheet type setting program that can prevent unnecessary switching of the sheet type setting mode without compromising the effectiveness of the auto-reset function, thereby smoothly executing image formation processing. [Means for solving the problem]

[0017] In order to achieve the above-mentioned object, an image forming apparatus according to one embodiment of the present disclosure has a media detection means for automatically detecting the sheet type and a user specification means for accepting a user specification of the sheet type, and is set by default to either an automatic detection mode that prioritizes automatic detection or a user specification mode that prioritizes user specification, and is characterized by comprising a setting mode acceptance means for accepting the specification of the setting mode, a reset means for changing the setting mode from the specified setting mode to the default setting, provided that specified reset conditions are met, and a prohibition means for prohibiting the reset means from changing the setting mode and maintaining the specified setting mode, provided that specified prohibition conditions are met.

[0018] In this case, a switching notification means may be provided to notify the user when the setting mode has been switched.

[0019] In addition, when the default setting mode is the automatic detection mode and the specified setting mode is the user-specified mode, the resetting means may change the setting mode to the automatic detection mode when a reset condition is satisfied.

[0020] The prohibiting means may prohibit the resetting means from changing the setting mode on the condition that the default setting mode is the automatic detection mode and the specified setting mode is the automatic detection mode.

[0021] Furthermore, the setting mode may be set as a default at the time of shipment to either the automatic detection mode or the user-specified mode.

[0022] The reset unit may change the setting mode on the condition that the device is in a standby state or is not accepting a print job.

[0023] The resetting unit may also set the reset condition to be the passage of a predetermined auto-reset time while no print job is being executed.

[0024] The prohibiting means may prohibit the resetting means from changing the setting mode on the condition that the execution of the print job is interrupted.

[0025] In addition, if a reset condition is satisfied while execution of a print job is interrupted, the prohibition means may prohibit a change of the setting mode until execution of a subsequent print job that has been accepted until the execution of the print job is completed is completed.

[0026] The device may also be provided with an interruption reason detection means for detecting paper empty, toner empty, and waste toner full as interruption reasons for interrupting the execution of a print job, and a job interruption means for interrupting the execution of a print job when an interruption reason is detected.

[0027] The device may also include a user operation accepting means for accepting user operations by displaying an operation screen related to copy, fax / scan, fax, box or web browser, and a screen operation reset means for invalidating user operations accepted on the operation screen after the operation screen is displayed, on the condition that no user operations are accepted for a predetermined time while the operation screen is being displayed.

[0028] The device may further include a reset instruction receiving means for receiving a reset instruction from a user, and the reset means may set the reset condition as receiving the reset instruction from the user.

[0029] The device may also include a reading means for reading a document, and a document transport means for transporting documents one by one from a stack of documents placed on a document tray to the reading means, the document transport means having a document detection means for detecting that a stack of documents has been placed on the document tray, and the reset means may have the placement of a stack of documents on the document tray as a reset condition.

[0030] Also, a user authentication means for performing user authentication may be provided, and the reset means may be reset when new user authentication has been performed.

[0031] The resetting means may also make the change when the operating mode of the device returns from a sleep mode as a reset condition.

[0032] Furthermore, when the setting mode accepted by the setting mode accepting means is a user-specified mode, the prohibiting means may set a prohibiting condition that the sheet type accepted as specified by the user is unacceptable paper, which is a sheet type that is likely to be erroneously detected by the media detecting means.

[0033] Furthermore, the prohibition means may automatically detect the sheet type when the setting mode accepted by the setting mode acceptance means is a user-specified mode, and the prohibition condition may be that the automatically detected sheet type is unacceptable paper, which is a sheet type that is likely to be erroneously detected by the media detection means.

[0034] Furthermore, when the resetting means switches the setting mode from the user-specified mode to the automatic detection mode, the sheet type may be automatically detected from the first recording sheet of the next print job to be executed.

[0035] In addition, when the prohibiting means prohibits the resetting means from switching the setting mode from the user-specified mode to the automatic detection mode, the setting mode may be maintained in the user-specified mode until the sheet type is automatically detected for the first recording sheet of the next print job to be started.

[0036] In addition, an openable paper feed cassette is provided to supply recording sheets to be used for printing, and when the reset means switches the setting mode from the user-specified mode to the automatic detection mode, the sheet type may be automatically detected by the first recording sheet supplied from the paper feed cassette after the paper feed cassette is opened and closed next time.

[0037] In addition, if an openable / closable paper feed cassette is provided to supply recording sheets to be used for printing, and if the prohibiting means prohibits the resetting means from switching the setting mode from the user-specified mode to the automatic detection mode, the setting mode may be maintained in the user-specified mode until the sheet type is automatically detected for the first recording sheet supplied from the paper feed cassette after the paper feed cassette is next opened and closed.

[0038] The reset means may also change the setting mode from the specified setting mode to the default setting on the condition that the execution of the print job currently being executed is completed when the reset condition is satisfied, and further on the condition that if a subsequent print job is accepted during the execution of the print job, the execution of the subsequent print job is completed.

[0039] Furthermore, when the prohibiting means prohibits the resetting means from switching the setting mode from the user-specified mode to the automatic detection mode, the setting mode may be maintained in the user-specified mode until the execution of the print job being executed when the resetting condition is satisfied is completed, and further, if a subsequent print job is accepted during the execution of the print job, until the execution of the subsequent print job is completed.

[0040] In addition, the setting mode accepting means can accept the designation of the setting mode with administrator authority and user authority, and if the automatic detection mode is designated with administrator authority, the setting mode can be changed to the user-specified mode with user authority, while if the user-specified mode is designated with administrator authority, changing the setting mode to the automatic detection mode with user authority may be prohibited.

[0041] The media detection means may also determine the type of sheet by measuring at least one of the transmittance and reflectance of the recording sheet using an optical sensor.

[0042] Also, when the setting mode is the automatic detection mode, the print job is executed under image process conditions according to the automatically detected sheet type, and when the setting mode is the user-specified mode, the print job is executed under image process conditions according to the sheet type specified by the user.

[0043] Also, an image forming apparatus may have a media detection means that automatically detects the sheet type, and a setting mode that determines whether or not to set image process conditions according to the automatically detected sheet type is set as a default, and may include a setting mode acceptance means that accepts the designation of the setting mode, a reset means that changes the setting mode from the designated setting mode to the default setting, provided that specified reset conditions are met, and a prohibition means that prohibits the reset means from changing the setting mode and maintains the designated setting mode, provided that specified prohibition conditions are met. An image forming apparatus characterized by:

[0044] Furthermore, a sheet type setting method according to one embodiment of the present disclosure is a sheet type setting method executed by an image forming device that has a media detection means for automatically detecting the sheet type and a user specification means for accepting a user specification of the sheet type, and that is set by default to either an automatic detection mode that prioritizes automatic detection or a user specification mode that prioritizes user specification, and is characterized by including a setting mode acceptance step for accepting the specification of the setting mode, a reset step for changing the setting mode from the specified setting mode to the default setting when a specified reset condition is met, and a prohibition step for prohibiting the reset means from changing the setting mode and maintaining the specified setting mode, provided that a specified prohibition condition is met.

[0045] Furthermore, a sheet type setting program according to one embodiment of the present disclosure has a media detection means for automatically detecting the sheet type and a user specification means for accepting a user specification of the sheet type, and is executed by a computer mounted on an image forming device that is set by default to either an automatic detection mode that prioritizes automatic detection or a user specification mode that prioritizes user specification, and is characterized in that the program causes the computer to execute a setting mode acceptance step for accepting the specification of the setting mode, a reset step for changing the setting mode from the specified setting mode to the default setting when a specified reset condition is met, and an inhibition step for prohibiting the reset means from changing the setting mode and maintaining the specified setting mode, provided that a specified inhibition condition is met. [Effects of the Invention]

[0046] In this way, switching of the sheet type setting mode to the default setting can be prohibited using the necessity of the sheet type setting mode as a prohibition condition, so that the image forming process can be carried out smoothly. [Brief explanation of the drawings]

[0047] [Figure 1] 1 is a diagram showing a main configuration of an image forming apparatus 1 according to a first embodiment of the present disclosure. [Figure 2] 1A is a diagram showing the arrangement of the media detection sensor 120, and FIG. 1B is a diagram showing the configuration of the media detection sensor 120. FIG. [Figure 3] FIG. 2 is a block diagram showing the main components of a control unit 101. [Figure 4] (a) is a diagram illustrating the "Manual Feed - Paper Size and Type" screen 400 with the sheet type setting mode set to user-specified mode, (b) is a diagram illustrating the "Manual Feed - Paper Size and Type" screen 400 with the sheet type setting mode set to automatic detection mode, and (c) is a diagram illustrating another screen with the sheet type setting mode set to automatic detection mode. [Figure 5]10 is a flowchart illustrating an auto-reset operation of the image forming apparatus 1. [Figure 6] FIG. 6 is a diagram illustrating an example of a "paper type automatic detection setting" screen 600 that accepts default settings of a sheet type setting mode for each recording sheet supply source. [Figure 7] (a) is a table illustrating a secondary transfer voltage setting table that associates sheet types with secondary transfer voltages, (b) is a table illustrating a fixing temperature setting table that associates sheet types with fixing temperatures, and (c) is a table illustrating a sheet conveying speed setting table that associates sheet types with sheet conveying speeds. [Figure 8] (a) is a sequence diagram explaining the auto-reset operation when printing is not interrupted, (b) is a sequence diagram explaining the auto-reset operation when printing is interrupted, and (c) is a sequence diagram explaining the auto-reset operation when the next print job is accepted while a print job is being executed. [Figure 9] 10 is a flowchart illustrating an auto-reset operation when a next print job is accepted while a print job is being executed. [Figure 10] 10A is a diagram illustrating an example of an auto-reset setting selection screen 1000, FIG. 10B is a diagram illustrating an example of an auto-reset time setting screen 1010, and FIG. 10C is a diagram illustrating an example of a copy screen 1020. FIG. [Figure 11] (a) is a diagram for explaining the reset operation triggered by placing a stack of documents D on the document tray 153 of the automatic document transport unit 152, (b) is a diagram for explaining the reset operation triggered by card authentication, (c) is a diagram for explaining the reset operation triggered by selecting the "reset" key 1121, and (d) is a diagram for explaining the reset operation triggered by transitioning to sleep mode. [Figure 12] (a) is a flowchart explaining the operation of prohibiting the auto-reset operation depending on the strengths or weaknesses of automatic detection of the sheet type specified by the user, and (b) shows examples of sheet types, including unsuitable letters that are difficult to automatically detect accurately, and other types of sheets. [Figure 13] 10 is a flowchart illustrating an operation of prohibiting the auto-reset operation depending on whether the sheet type automatically detected during execution of a print job is unacceptable paper. DETAILED DESCRIPTION OF THE INVENTION

[0048] Hereinafter, embodiments of an image forming apparatus, a sheet type setting method, and a sheet type setting program according to the present disclosure will be described with reference to the accompanying drawings. [1] First embodiment In this embodiment, a case will be described in which the sheet type setting mode is prohibited from being automatically reset from the user-specified mode to the automatic detection mode when the execution of a print job is suspended. (1-1) Configuration of Image Forming Apparatus First, the configuration of the image forming apparatus according to this embodiment will be described.

[0049] As shown in FIG. 1, the image forming apparatus 1 according to this embodiment is a so-called tandem color multifunction peripheral (MFP: Multi-Function Peripheral) that combines functions such as printing, scanning, copying, facsimile, and BOX, and includes an image forming unit 100, a paper feed cabinet unit 140, an image reading unit 151, an automatic document feeder (ADF: Automatic Document Feeder) 152, and an operation panel 161.

[0050] The image forming unit 100 includes image forming units 111Y, 111M, 111C, and 111K that form toner images of yellow (Y), magenta (M), cyan (C), and black (K), respectively.

[0051] Each of the image forming units 111Y, 111M, 111C, and 111K includes a photosensitive drum, a charging device, a developing device, a primary transfer roller, and a cleaning device (not shown). The charging device uniformly charges the outer peripheral surface of the photosensitive drum. The exposure unit 112 forms an electrostatic latent image by irradiating the outer peripheral surface of the photosensitive drum with laser light modulated according to the image to be formed.

[0052] Toner bottles 113Y, 113M, 113C and 113K containing toner of each color YMCK are detachably attached to image forming apparatus 1, and supply toner to developing devices of image forming units 111Y, 111M, 111C and 111K, respectively.

[0053] The developing device develops the electrostatic latent image by supplying toner to the outer peripheral surface of the photosensitive drum. The primary transfer roller electrostatically transfers the toner image from the outer peripheral surface of the photosensitive drum onto the outer peripheral surface of the intermediate transfer belt 114 (primary transfer).

[0054] The image forming apparatus 1 counts the number of dots per page for image data of each color of YMCK. By calculating the cumulative value of this number of dots, it is possible to determine whether the toner of each color of YMCK contained in the toner bottles 113Y, 113M, 113C, and 113K has been used up and the toner bottles have become "toner empty."

[0055] The image forming units 111Y, 111M, 111C, and 111K perform primary transfer of the toner images of each color, YMCK, onto the outer circumferential surface of the intermediate transfer belt 114 so that they overlap each other, thereby forming a color toner image on the outer circumferential surface of the intermediate transfer belt 114. When forming a monochrome toner image, only a toner image of one color is transferred onto the outer circumferential surface of the intermediate transfer belt 114, and toner images of other colors are not formed in the first place.

[0056] After the primary transfer, the toner remaining on the outer peripheral surface of the photosensitive drum is scraped off by a cleaning device and then collected in a waste toner box (not shown).

[0057] Intermediate transfer belt 114 is an endless belt member that runs around drive roller 115, driven roller 116, and primary transfer rollers of image forming units 111Y, 111M, 111C, and 111K, and travels in the direction of arrow A.

[0058] The drive roller 115 sandwiches the intermediate transfer belt 114 and presses it against the secondary transfer roller 117 to form a secondary transfer nip. The intermediate transfer belt 114 travels in the direction of arrow A, thereby transporting the toner image carried on its outer circumferential surface to the secondary transfer nip.

[0059] A stack of recording sheets is accommodated in each of the sheet feed cassettes 135a and 135b of the image forming unit 100 and the sheet feed cassettes 135c and 135d of the sheet feed cabinet unit 140. In addition, a stack of recording sheets may be placed on the multi manual sheet feed tray 121.

[0060] The paper feed cassettes 135a, 135b, 135c, and 135b and the multi manual paper feed tray 121 constitute a paper feed unit 171. The paper feed unit 171 may include a large capacity cassette (LCC) or a large capacity unit (LU).

[0061] Sheet sensors (not shown) are provided in each of the paper feed cassettes 135a, 135b, 135c, and 135b and the multi manual feed tray 121. The sheet sensors are used to monitor whether recording sheets are stored in each of the paper feed cassettes 135a, 135b, 135c, and 135b and the multi manual feed tray 121.

[0062] When the recording sheets stored in the paper feed cassettes 135a, 135b, 135c, and 135b or the multi manual paper feed tray 121 run out, it is determined that the paper is empty.

[0063] Paper feed rollers 133a, 133b, 133c, and 133d feed recording sheets sequentially from the top of the stack of recording sheets stored in paper feed cassettes 135a, 135b, 135c, and 135d, respectively. Paper feed roller 134 feeds recording sheets sequentially from the top of the stack of recording sheets placed on multi manual paper feed tray 121.

[0064] When a recording sheet is transported from paper feed cassettes 135a, 135b, 135c, and 135d or multi manual paper feed tray 121 to the secondary transfer nip, it passes through the detection position of media detection sensor 120. Media detection sensor 120 outputs a detection signal for estimating the type of recording sheet.

[0065] In this embodiment, the media detection sensor 120 is an optical sensor, as described below, that irradiates the recording sheet with illumination light and detects the amount of light reflected from the recording sheet, as well as the amount of light transmitted through the recording sheet.

[0066] The control unit 101 estimates the type of recording sheet (hereinafter referred to as "sheet type") by referring to the detection signal output by the media detection sensor 120. In this embodiment, the detection signal output by the media detection sensor 120 indicates the reflectance and transmittance of the recording sheet.

[0067] After passing the detection position of the media detection sensor 120, the recording sheet reaches the registration roller 132. The registration roller 132 stops rotating when the recording sheet reaches it, and the recording sheet is further conveyed with its leading edge abutting against the conveyance nip of the registration roller 132, forming a loop.

[0068] Thereafter, the registration rollers 132 are rotated in synchronization with the timing of the conveyance of the toner image by the intermediate transfer belt 114, and convey the recording sheet to the secondary transfer nip.

[0069] A secondary transfer bias is applied to the secondary transfer roller 117, and the toner image is electrostatically transferred (secondary transfer) from the outer peripheral surface of the intermediate transfer belt 114 onto the recording sheet. The recording sheet onto which the toner image has been secondarily transferred is transported to a fixing unit 122, where the toner image is thermally fixed.

[0070] After the secondary transfer, the toner remaining on the outer peripheral surface of the intermediate transfer belt 114 is scraped off by a cleaning device 118 and then collected in a waste toner box. A toner sensor (not shown) that detects the amount of collected toner is provided in the waste toner box. The toner sensor determines whether the amount of collected toner has exceeded a predetermined amount, i.e., the "waste toner full" state.

[0071] Fixing unit 122 includes a pressure roller 129, a fixing roller 130, and a halogen heater 131. Pressure roller 129 is urged toward fixing roller 130 by a urging member (not shown). This urging brings pressure roller 129 into contact with fixing roller 130, forming a fixing nip. Halogen heater 131 heats fixing roller 130 to increase its temperature.

[0072] When pressure roller 129 is driven to rotate by a drive source (not shown), fixing roller 130 rotates following pressure roller 129. This rotation causes a recording sheet to pass through the fixing nip. When a recording sheet is passed through the fixing nip while fixing roller 130 is heated, the toner image on the recording sheet is melted and pressure-bonded to the recording sheet (thermal fixing).

[0073] It should be noted that instead of the fixing roller 130, a fixing rotor other than the fixing roller 130, such as a fixing belt, may be used. Also, with regard to the pressure roller 129, a pressure member other than the pressure roller 129, such as a pressure pad, may be brought into pressure contact with the fixing rotor. When a pressure pad is used as the pressure member, the fixing rotor may be rotated using a drive source.

[0074] The fixing rotator may be heated by a heat source other than the halogen heater 131, such as an induction heater, and the temperature is adjusted to a fixing temperature appropriate for the type of sheet. The temperature adjustment is performed, for example, by repeatedly measuring the surface temperature of the fixing member and feedback-controlling the output of the heat source depending on the level of the obtained surface temperature.

[0075] To explain the relationship between the fixing process and the recording sheet, cardboard has a larger basis weight and therefore a larger heat capacity than regular paper, so when thermally fixing a toner image on cardboard, the fixing temperature is higher and the sheet conveyance speed (system speed) is slower than when thermally fixing a toner image on regular paper. If the fixing temperature is higher, more heat is applied to the recording sheet during thermal fixing, so the toner image can be reliably melted even if the recording sheet has a large heat capacity.

[0076] Furthermore, if the sheet transport speed is slowed, the recording sheet transport speed and other factors slow down, so the thermal fixation takes that much longer. As a result, the amount of heat applied to the recording sheet during thermal fixation also increases, so even if the recording sheet has a large heat capacity, the toner image can be reliably melted. The fixing temperature and sheet transport speed constitute image process conditions.

[0077] The image process conditions also include a secondary transfer voltage for secondary transfer of toner onto the recording sheet. Different types of recording sheets have different volume resistivity and surface resistivity, which results in different optimal secondary transfer voltages. For this reason, like the fixing temperature and sheet conveyance speed, it is desirable to set the secondary transfer voltage according to the type of recording sheet.

[0078] A switching claw 123 switches the transport direction of the recording sheet on which the toner image has been thermally fixed. When an image is to be formed on the back side of the recording sheet, the switching claw 123 guides the recording sheet to a reversing roller 126. When the reversing roller 126 transports the recording sheet until part of the recording sheet advances onto a switchback tray 127, the position of the switching claw 123 switches.

[0079] Thereafter, when the reversing roller 126 reverses its rotation direction, the recording sheet is sent to a double-sided reversing path 128. The recording sheet sent to the double-sided reversing path 128 is transported again to the secondary transfer nip via the registration roller 132, where a toner image is secondarily transferred onto the back surface, and the toner image is thermally fixed.

[0080] When forming an image on the back side of the recording sheet, the sheet type has already been detected when forming an image on the front side of the recording sheet, so there is no need to use the media detection sensor 120 to detect the sheet type again.

[0081] When single-sided printing or double-sided printing is completed, the switching claw 123 guides the recording sheet to the paper discharge rollers 124. The paper discharge rollers 124 discharge the recording sheet onto the paper discharge tray 125.

[0082] The control unit 101 monitors and controls the operation of the image forming apparatus 1. In particular, the control unit 101 sets image process conditions according to the sheet type estimated by referring to the output signal of the media detection sensor 120 and the sheet type designated by the user.

[0083] The image reading unit 151 reads an original and generates image data. When copying an original, the image forming unit 100 uses the image data generated by the image reading unit 151 to perform printing.

[0084] When reading an original document using the sheet-through method, image reading unit 151 uses automatic document transport unit 152 to feed the original document one by one from the top of a stack of original documents placed on document tray 153 and transport it to a document reading position. Image reading unit 151 reads the original document passing through the reading position with a line sensor (not shown) and generates image data.

[0085] As will be described later, an original sensor (not shown) is provided on the original tray 153. The original sensor is a sensor for detecting whether a stack of originals is placed on the original tray 153.

[0086] When reading an original document using the platen set method, the image reading unit 151 reads the original document while moving a line sensor (not shown) along the reading surface of the original document placed on a platen glass (not shown) and generates image data.

[0087] The operation panel 161 is used to present information to the user of the image forming apparatus 1 by video and audio, and to receive instructions input by the user. (1-2) Media detection sensor 120 Next, the media detection sensor 120 will be described.

[0088] The image forming apparatus 1 has two setting modes for setting the sheet type of the recording sheet. One is a user-specified mode in which the user of the image forming apparatus 1 specifies the sheet type of the recording sheet, and the other is an automatic detection mode in which the image forming apparatus 1 determines the sheet type of the recording sheet by itself without any user operation. In the automatic detection mode, the image forming apparatus 1 uses the media detection sensor 120 to automatically determine the sheet type of the recording sheet.

[0089] As shown in Figure 2(a), the media detection sensor 120 is located immediately downstream of the confluence of the paper feed path 211 from the paper feed cassette 135a, the paper feed path 213 from the multi-manual paper feed tray 121, and the paper feed path 212 from the paper feed cassettes 135b, 135c, and 135d, and upstream of the registration roller 132.

[0090] In this embodiment, the media detection sensor 120 is attached to the transport guide plates 221 and 222 that guide the recording sheet to the registration rollers 132, but it may also be fixed to another member. In this way, regardless of which of the paper feed paths 211, 212, and 213 the recording sheet is fed through, the media detection sensor 120 can be used to determine the sheet type.

[0091] 2(b), the media detection sensor 120 includes a light-emitting substrate 231 and a light-receiving and light-emitting substrate 241. An LED (Light Emitting Diode) 232 that emits near-infrared light IR and an LED 233 that emits blue light B are mounted on the light-emitting substrate 231. The light IR and B emitted from the LEDs 232 and 233 are irradiated onto the recording sheet S via a through-hole 224 provided in the conveyance guide plate 222. A portion of the light irradiated onto the recording sheet S is transmitted and heads toward the light-receiving and light-emitting substrate 241.

[0092] Furthermore, an LED 242 that emits green light G and a photodiode 243 that outputs a detection signal according to the amount of incident light are mounted on the light receiving and emitting substrate 241. The light G emitted from the LED 242 passes through a through hole 223 provided in the conveying guide plate 221 and is irradiated onto the recording sheet S. A portion of the light irradiated onto the recording sheet S is reflected and directed toward the photodiode 243.

[0093] If there is no recording sheet S on the optical path of the near-infrared light IR and blue light B traveling from the LEDs 232, 233 to the photodiode 243, the near-infrared light IR and blue light B will be directly incident on the photodiode 243 without being blocked by the recording sheet S. Using this incident light amount as a reference, the transmittance of the near-infrared light IR and blue light B is evaluated for each recording sheet.

[0094] A reflective light source reference plate 251 is disposed on the surface of the transport guide plate 222 facing the light receiving and emitting substrate 241, at a position where the emitted light G from the LED 242 is incident. When a recording sheet S is not present on the optical path of the green light G traveling from the LED 242 to the reflective light source reference plate 251 or on the optical path of the green light G traveling from the reflective light source reference plate 251 to the photodiode 243, the green light G is not blocked by the recording sheet S, but is reflected by the reflective light source reference plate 251 and enters the photodiode 243. The reflectance of the green light G is evaluated for each recording sheet based on this incident light amount.

[0095] Since the transmittance and reflectance of near-infrared light IR, blue light B, and green light G may vary depending on the basis weight of the recording sheet S, the basis weight of the recording sheet S can be determined by referring to the detection signal of the photodiode 243 and calculating the transmittance of near-infrared light IR and blue light B, or calculating the reflectance of green light G.

[0096] A sheet sensor (not shown) is arranged upstream of the media detection sensor 120 in the conveying direction of the recording sheet, and after a predetermined time has elapsed since the sheet sensor detected the leading edge of the recording sheet, the media detection sensor 120 sequentially emits light from LEDs 232, 233, and 242, and detects the amount of light transmitted and reflected by the recording sheet S with a photodiode 243, respectively. (1-3) Configuration of the control unit 101 Next, the configuration of the control unit 101 will be described.

[0097] As shown in FIG. 3, the control unit 101 includes a CPU (Central Processing Unit) 301, a non-volatile memory called ROM (Read Only Memory) 302, a volatile memory called RAM (Random Access Memory) 303, and the like, all of which are interconnected via an internal bus 307 for mutual communication.

[0098] When a reset signal is input, triggered by powering on the image forming apparatus 1, the CPU 301 reads and starts a boot program from the ROM 302, and executes an OS (Operating System) and control programs read from an HDD (Hard Disk Drive) 304, which is an auxiliary storage device, using the RAM 303 as a working storage area. Note that instead of the HDD 304, an SSD (Solid State Drive) may be used as the auxiliary storage device.

[0099] Timer 305 is used to determine the current time and measure elapsed time such as the time required to transport a recording sheet. In this embodiment, when timer 305 is instructed to start measuring time after accepting a time setting, it inputs a timer interrupt to CPU 301 as soon as the set time has elapsed. This timer interrupt enables CPU 301 to detect the time-out of the set time.

[0100] A NIC (Network Interface Card) 306 executes processing for communicating with other devices via a communication network such as a LAN (Local Area Network) or the Internet. This allows the image forming device to accept image formation jobs from other devices. An image formation job may include settings for the sheet type of recording sheets to be used in the image forming process.

[0101] The control unit 101 uses the operation panel 161 to present information to the user of the image forming apparatus 1 and to accept instruction inputs from the user. For example, the control unit 101 accepts an instruction from the user to execute an image forming process and accepts settings for the sheet type of the recording sheet to be used in the image forming process.

[0102] If paper feed unit 119 is equipped with multiple paper feed cassettes, the sheet type of the recording sheets stored in each paper feed cassette may be specified. Also, when paper is fed from multi manual paper feed tray 121, the sheet type is specified by the user using operation panel 161.

[0103] The control unit 101 further includes a facsimile communication interface (not shown) and is capable of transmitting and receiving facsimile data. Image data generated by scanning an original document with the image reading unit 151 may be used as the facsimile data to be transmitted by facsimile, or such image data may be temporarily stored in a large-capacity storage device such as the HDD 304 before being transmitted by facsimile.

[0104] 4(a), the operation panel 161 includes a touch panel 400, a power key 401, hard keys 402, a start key 403, a stop key 404, and a reset key 405. The touch panel 400 includes a liquid crystal display (LCD) and a touch pad, and displays a screen to the user of the image forming apparatus 1 and receives touch inputs from the user.

[0105] The power key 401 is a key for turning on the power of the image forming apparatus 1, and the hard keys 402 can be customized by the user to set a function to be executed when pressed. The start key 403 is a key for starting execution of a process such as copying after the user has completed setting the execution conditions for that process.

[0106] A stop key 404 is a key for stopping a process such as an image forming process that is currently being executed, etc. A reset key 405 is a key for resetting the settings on the currently displayed screen.

[0107] 4(a), the "Manual Feed - Paper Size and Type" screen is displayed on the liquid crystal display of the touch panel 400. The "Manual Feed - Paper Size and Type" screen is a display screen for setting the paper size and sheet type of the recording sheets to be fed from the multi-manual paper feed tray 121.

[0108] The "Manual Feed - Paper Size and Type" screen can be switched between a "Paper Size" screen for setting the paper size and a "Paper Type" screen for setting the sheet type. The "Paper Type" screen is shown in FIGS. 4(a) and 4(b). On the "Paper Type" screen, slide switch 406 can be used to set whether the sheet type of the recording sheet is automatically detected or specified by the user.

[0109] Hereinafter, among the setting modes for setting the sheet type of the recording sheet, the setting mode that automatically detects the sheet type of the recording sheet using the media detection sensor 120 will be referred to as the "automatic detection mode," and the setting mode that allows the user to specify the sheet type on the "Paper Type" screen will be referred to as the "user-specified mode."

[0110] In FIG. 4A, the slide switch 406 is set to "OFF," so the sheet type setting mode is set to a user specification mode in which automatic detection is not performed and user specification is accepted.

[0111] On the other hand, in FIG. 4(b), only the display screen of the touch panel 400 is shown, and the slide switch 406 is "ON", so the sheet type setting mode is set to the automatic detection mode, which performs automatic detection.

[0112] On the "Paper Type" screen, the setting mode can be set individually for each of paper feed cassettes 135a, 135b, 135c, and 135d that make up paper feed unit 171 and multi manual paper feed tray 121. By visually checking slide switch 406, the user of image forming apparatus 1 can confirm whether the setting mode is the automatic detection mode or the user-specified mode.

[0113] In Figure 4(a) and (b), the sheet type that can be specified by the user is "plain paper (60-90 g / m 2 )”, “Plain paper+(91-105g / m 2 )," "Single-sided paper (60-90 g / m 2 )”, “Special paper (60-90g / m 2 ) and "Cardboard 1 (106-120 g / m 2 )," "Cardboard 1+ (121-157g / m 2 )" is listed.

[0114] However, it goes without saying that the present disclosure is not limited to these sheet types, and in addition to these sheet types, "thin paper (52-29 g / m 2 )," "Cardboard 2 (158-209g / m2 ), "Cardboard 3 (210-256 g / m 2 ), "Cardboard 4 (257-300g / m 2 )”, “Recycled paper (50-140g / m 2 ) and "Coated paper (73-157g / m 2 )" may be specified by the user.

[0115] In the above brackets, the values ​​in the parentheses indicate the range of basis weight for each sheet type.

[0116] It goes without saying that the GUI (Graphical User Interface) component that accepts the setting mode is not limited to the slide switch 406, and the setting mode designation may be accepted using another GUI component instead of the slide switch 406. For example, as shown in FIG. 4(c), the setting mode designation may be accepted using a check box 410.

[0117] When the check box 410 is checked, it indicates that the setting mode is the automatic detection mode. When the check box 410 is unchecked, it indicates that the setting mode is the user-specified mode, not the automatic detection mode.

[0118] The sheet type setting mode is set to either the automatic detection mode or the user setting mode when the image forming apparatus 1 is shipped. Setting the setting mode to the automatic detection mode when shipped saves the user the trouble of setting the sheet type, which is effective for user convenience. (1-4) Auto-reset operation Next, the auto-reset operation of the sheet type setting mode will be described. Note that in this embodiment, the case where the default setting of the sheet type setting mode is the automatic detection mode will be described as an example. Therefore, the automatic detection mode is the default setting mode, and the user-specified mode is the non-default setting mode.

[0119] As shown in FIG. 5, when the user sets the sheet type setting mode to the user-specified mode on the operation panel 161 (S501: YES), the image forming apparatus 1 enables the auto-reset function (S502).

[0120] The user may operate the slide switch 406 or check box 410 as described above to set the sheet type setting mode to the user-specified mode, and then the user may specify the sheet type, or the user may specify the sheet type regardless of whether the sheet type setting mode is the user-specified mode or the automatic detection mode.

[0121] Furthermore, when the image forming apparatus 1 receives an operation to specify a sheet type by a user, the image forming apparatus 1 may automatically change the sheet type setting mode to the user-specified mode. In any case, the user-specified mode is the setting mode specified by the user.

[0122] When the auto-reset function is enabled, if the state in which image formation processing is not being performed continues for a predetermined time (hereinafter referred to as the "auto-reset time") (reset condition), the sheet type setting mode is reset and returns to the default setting. The auto-reset time is set to a default value when the image forming apparatus 1 is shipped, and may be changed by an administrator or user of the image forming apparatus 1 after shipping.

[0123] 6 shows an example of a paper type automatic detection setting screen 600 on which default values ​​for the sheet type setting mode can be set only with administrator privileges. In Fig. 6, slide switches 601 to 605 are used to set default values ​​for the sheet type setting mode for all of the paper feed trays 135a, 135b, 135c, and 135d, and the multi manual feed tray 121, including "feed tray 1," "feed tray 2," "feed tray 3," "feed tray 4," and "manual feed tray," respectively.

[0124] In Figure 6, slide switches 601 to 605 are shown as an example in which, when slid to the ON side, the default value of the sheet type setting mode is set to automatic detection mode, and when slid to the OFF side, the default value of the sheet type setting mode is set to user-specified mode, but it goes without saying that the ON and OFF positions may be reversed.

[0125] When the default value of the sheet type setting mode is set to the automatic detection mode with administrator authority, it is possible to permit the general user authority to change the default value of the sheet type setting mode to the user specified mode, and when the default value of the sheet type setting mode is set to the user specified mode with administrator authority, it is possible to prohibit the general user authority from changing the default value of the sheet type setting mode to the automatic detection mode.

[0126] In the case where the default value of the sheet type setting mode is to be changed with general user authority, a separate automatic paper type detection setting screen 600 similar to that shown in Fig. 6 may be prepared. Also, operations under general user authority on the automatic paper type detection setting screen 600 similar to that shown in Fig. 6 may be permitted to change the default value of the sheet type setting mode.

[0127] When an image is formed by the user operating the operation panel 161 or by receiving a print job from another device via a communication network (S503: YES), the sheet type setting mode is first confirmed.

[0128] If the sheet type setting mode is the user-specified mode (S504: user-specified), the image forming apparatus 1 sets image process conditions according to the sheet type specified by the user, and starts the image forming process (S505).

[0129] On the other hand, if the sheet type setting mode is the automatic detection mode (S504: automatic detection), the image forming apparatus 1 starts the image forming process (S506). As a result, when recording sheets are supplied from the paper feed unit 171, the sheet type of the first recording sheet is automatically detected by the media detection sensor 120, and image process conditions are set according to the automatically detected sheet type (S507).

[0130] The image process conditions include, for example, a secondary transfer voltage, a fixing temperature, a sheet conveying speed, etc. In order to set the secondary transfer voltage according to the type of recording sheet, a table such as that shown in FIG.

[0131] 7A shows a setting table in which the sheet type of the recording sheet corresponds to the setting value of the secondary transfer voltage in a normal temperature and normal humidity environment (NN environment). In the column for the sheet type of the recording sheet, the basis weight corresponding to the sheet type of the recording sheet is written in parentheses.

[0132] For example, if the sheet type of the recording sheet is "Thin paper (52-59 g / m 2 )" the secondary transfer voltage is set to "1,450V". 2 ), "Cardboard 3 (210-256 g / m 2 ) and "Cardboard 4 (257-300 g / m 2 ) the secondary transfer voltages are both set to "1,950V".

[0133] The setting table shown in FIG. 7B associates the set value of the fixing temperature under a normal temperature and normal humidity environment with the sheet type of the recording sheet. For example, if the sheet type of the recording sheet is "plain paper + (91-105 g / m 2 ), "Cardboard 1 (106-120g / m 2 )," "Cardboard 1+ (121-157g / m 2 ) and "Cardboard 2 (158-209 g / m 2 )" the fixing temperature is set to "140°C" for both.

[0134] In the setting table shown in FIG. 7(a), the sheet type of the recording sheet is set to "Plain paper + (91-105 g / m 2 )" the secondary transfer voltage is set to "1,850V" and the sheet type of the recording sheet is "Thick paper 1 (106-120g / m 2 )" or "Cardboard 1+ (121-157g / m 2 )" the secondary transfer voltage is set to "1,550V" and the sheet type of the recording sheet is "Thick Paper 2 (158-209g / m 2 ) the secondary transfer voltage is set to "1,950V."

[0135] In this way, the range of sheet types for which the image process conditions are common may differ depending on which image process conditions are set, so it is necessary to provide a setting table for each image process condition.

[0136] FIG. 7C shows an example of a setting table for the sheet transport speed. The sheet transport speed can be switched between two stages. In the setting table of FIG. 7C, the sheet type of the recording sheet is set to "plain paper + (91-105 g / m 2 )" or "Plain paper + (91-105 g / m 2 For recording sheets of a sheet type with a basis weight less than that of the "165 mm / sec.", the sheet conveying speed is set to the full speed of "165 mm / sec."

[0137] Also, if the sheet type of the recording sheet is "Thick paper 1 (106-120 g / m 2 ) or "Cardboard 1 (106-120 g / m 2 For recording sheets with a basis weight greater than that of the standard 100 mm / s, the amount of heat required to thermally fix the toner image is greater than for recording sheets with a lower basis weight, so the sheet transport speed is set to half the speed, 82.5 mm / s.

[0138] Thereafter, if a reason for interrupting the image forming process, such as paper empty, toner empty, or waste toner full, occurs (S508: Interrupt), it is confirmed whether the reason for interrupting the image forming process has been resolved.

[0139] If the reason for interrupting the image forming process has not been resolved and continues (S509: Continue), it is checked whether the auto-reset time has elapsed while the image forming process was interrupted.

[0140] In this embodiment, the auto-reset function is enabled (S502) only when the sheet type setting mode is the user-specified mode (S501: YES). Therefore, when the sheet type setting mode is the automatic detection mode, it is not checked whether the auto-reset time has elapsed.

[0141] However, it goes without saying that the present disclosure is not limited to this, and it is also possible to check whether the auto-reset time has elapsed even when the sheet type setting mode is the automatic detection mode. In this case, in step S511 described below, the sheet type setting mode is prohibited from being returned to the default setting, and the current sheet type setting mode is maintained as is.

[0142] If the auto-reset time has elapsed (S510: YES), the auto-reset function is prohibited from restoring the sheet type setting mode to the default setting, and the setting mode is maintained in the user-specified mode (S511). In this way, even if the execution of the image forming process is resumed, the sheet type setting mode is maintained in the user-specified mode. Therefore, unless the user changes the sheet type setting, the sheet type setting is maintained, and problems that may arise from changing the sheet type setting can be avoided by automatically detecting the sheet type.

[0143] In this embodiment, when the sheet type setting mode is the automatic detection mode, the sheet type setting mode is set to the default setting, and therefore the auto-reset function does not operate.

[0144] For this reason, in the automatic detection mode, steps S510 and S511 are not executed, and the image formation process remains suspended until it is determined in step S509 that the reason for the suspension of the image formation process has been "resolved." If it is determined that the reason for the suspension of the image formation process has been "resolved," the process proceeds to step S512.

[0145] If no reason for interrupting the image forming process has occurred (S508: Continue), or after the reason for interrupting the image forming process has been resolved (S509: Resolved), or when the image forming process is completed (S512: YES), the sheet type setting mode is checked.

[0146] If the sheet type setting mode is the user-specified mode (S513: user-specified), it is confirmed whether or not the elapse of the auto-reset time has been detected before the image forming process is completed.

[0147] If it is detected that the auto-reset time has elapsed before the image forming process is completed (S514: YES), the sheet type setting mode is switched to the default setting (automatic detection mode) (S516).

[0148] If the elapse of the auto-reset time is not detected before the image formation process is completed (S514: NO), the process waits for the elapse of the auto-reset time (S515: YES) and switches the sheet type setting mode to the default setting (automatic detection mode) (S516).

[0149] In step S515, the image forming apparatus 1 waits for the auto-reset time to elapse on the condition that the apparatus state is standby or that a print job is not being accepted. For example, if a print job is accepted before the auto-reset time has elapsed, the process stops waiting for the auto-reset time to elapse, and proceeds to step S504 to repeat the above process.

[0150] After the process of step S516 is completed, or if the sheet type setting mode is set to the automatic detection mode and image forming process is executed (S513: automatic detection), the process proceeds to step S501 and the above process is repeated.

[0151] In this way, even if the auto-reset time has elapsed from the start to the completion of the image formation process, in other words, while the image formation process is being executed, including the period when the execution of the image formation process is temporarily suspended, the sheet type setting mode will remain in the user-specified mode. On the other hand, in other cases, i.e., during the period when the image formation process is not being executed, specifically when the image forming device 1 is on standby or when no print job is being accepted, once the auto-reset time has elapsed, the auto-reset function will return the sheet type setting mode from the user-specified mode to the default setting, automatic detection mode.

[0152] Therefore, the sheet type designated by the user is maintained, so that it is possible to prevent the image forming process from being stopped due to a paper mismatch, which would reduce user convenience, but the effect of the auto-reset function is not impaired.

[0153] Note that when the sheet type setting mode is automatically reset to the default setting in step S516, a message to that effect may be displayed on the operation panel 161 to notify the user. Such a change in the sheet type setting mode can be indicated by, for example, restoring the slide switch 406 or check box 410 to the default setting. (1-5) Example of auto-reset operation Next, the auto-reset function according to this embodiment will be described with an example of its operation. (1-5-1) Auto-reset operation First, a case where only one print job is executed will be described. As shown in Fig. 8(a), when there is no print job to be executed, the image forming apparatus 1 is on standby, and the sheet type setting mode is the user-specified mode, if a print job is accepted, the image forming apparatus 1 starts executing the print job (starts printing).

[0154] Thereafter, when a predetermined auto-reset time has elapsed since the image forming device 1 completed the execution of the print job (step S515: YES in FIG. 5), the auto-reset function returns the sheet type setting mode from the user-specified mode to the default automatic detection mode.

[0155] In this way, even if a print job is executed by specifying the sheet type in the user specification mode, the sheet type setting mode is returned to the default setting by the auto-reset function after the execution of the print job is completed, so that when a print job is executed thereafter, it is possible to prevent a new print job from being executed with the sheet type specified by the user who submitted the previous print job, against the will of the user who submitted the print job. (1-5-2) Disable auto-reset before print job completion On the other hand, if the execution of a print job is interrupted due to an interruption event such as paper empty, toner empty, or waste toner full during execution of the print job, the timing is started in the same way as when the execution of the print job is completed, and it is determined whether the auto-reset time has elapsed.

[0156] In this embodiment, even if the auto-reset time has elapsed since the execution of the print job was interrupted, auto-reset is prohibited and the sheet type setting mode continues in the user-specified mode without returning to the default setting, as shown in Figure 8(b).

[0157] In this way, even if the execution of the print job is subsequently resumed, the print job can be executed with the same sheet type settings as before the execution of the print job was interrupted.

[0158] On the other hand, if auto-reset is not prohibited, the sheet type setting mode will return to the default setting, automatic detection mode, and the print job will resume and the sheet type will be automatically detected. If the automatically detected sheet type differs from the sheet type specified in the print job, the print job will not be able to be executed due to a paper mismatch.

[0159] According to this embodiment, it is possible to avoid such a situation where a print job cannot be executed.

[0160] After that, when the reason for the interruption is resolved, the print job resumes and is executed in the user-specified mode with the sheet type specified by the user.When the print job is completed, since auto-reset was prohibited (step S514 in FIG. 5: YES), the sheet type setting mode is immediately returned to the default setting (automatic detection mode).

[0161] In this case, too, just as in the case where the execution of the print job is not interrupted, the sheet type setting mode may be returned to the default setting (automatic detection mode) after the auto-reset time has elapsed since the execution of the print job is completed.

[0162] Furthermore, in the above, we have described a case where auto-reset is prohibited and the user-specified mode continues as the sheet type setting mode, but it goes without saying that the present disclosure is not limited to this, and instead, the user may continue to specify the sheet type.

[0163] In this case, the user may be allowed to select whether to continue the sheet type setting mode or to continue with the sheet type specified by the user.

[0164] Furthermore, if the sheet type setting mode is returned to the default setting (automatic detection mode) after the execution of a print job is completed and before the execution of the next print job is started, the sheet type of the first recording sheet will be automatically detected when the execution of the next print job is started.

[0165] However, if automatic detection of the sheet type every time a print job is executed reduces productivity, the sheet type may be automatically detected only when the paper feed cassette in which paper is empty is opened and closed.

[0166] Since each paper feed cassette normally contains only one type of recording sheet, the type of recording sheets fed from a paper feed cassette that is not opened or closed almost always remains the same.

[0167] Furthermore, unless the paper cassette is empty, even if the paper cassette is opened and closed, it is rare for a recording sheet of a different type to be replenished from the recording sheets originally stored in the paper cassette. Furthermore, when a recording sheet of a different type to the recording sheets originally stored in the paper cassette is replenished, automatic detection is not performed because the user often sets the sheet type of the recording sheets.

[0168] Therefore, if the sheet type is automatically detected only when the paper feed cassette in which paper is empty is opened or closed, it is possible to suppress the decrease in productivity caused by the automatic detection of the sheet type, while at the same time eliminating the need for the user to specify the sheet type and enabling the sheet type to be set with high accuracy.

[0169] In this case, after the sheet type setting mode is restored to the default setting, the user may be allowed to select whether to automatically detect the sheet type of the first recording sheet when executing a print job for the first time, or whether to automatically detect the sheet type of the first recording sheet fed from a paper feed cassette after opening and closing the paper feed cassette that has become paper empty. (1-5-3) When there are consecutive print jobs During the execution of a print job, subsequent print jobs such as the next print job and the print job after that may be accepted.

[0170] As shown in Figure 8(c), if the next print job is accepted while a print job is being executed, the next print job will start immediately after the print job is completed without waiting for the auto-reset time to elapse. After that, if the auto-reset time has elapsed without a print job being executed after the print job is completed, the sheet type setting mode will return to the default setting.

[0171] To perform such an operation, the process shown in Fig. 9 can be added to the flowchart of Fig. 5. That is, if it is determined in step S514 of Fig. 5 that the passage of the auto-reset time has not been detected during execution of a print job (S514: NO), and if a new print job has been accepted during execution of the print job (S901: YES), the process proceeds to step S504 of Fig. 5, where the newly accepted print job is executed.

[0172] If no new print job is accepted during execution of the current print job (S901: NO), the auto-reset time is awaited (S515: YES), and the sheet type setting mode is returned to the default setting (automatic detection mode) (S516).

[0173] The same applies to the case where two or more print jobs are accepted while a print job is being executed.

[0174] Although image forming device 1 is often shared by multiple users, it is rare for the device to become congested with many users trying to use it at the same time, so if multiple print jobs are submitted in succession, they may be from the same user.

[0175] Therefore, if the sheet type is specified by the user for the first print job submitted, it is likely that the same user will also submit subsequent print jobs, and will expect that the same sheet type to be applied.

[0176] On the other hand, when automatically detecting the sheet type of recording sheets, some sheet types can be detected accurately, while others are prone to false detection. Therefore, in the above-mentioned cases, if the sheet type of recording sheets is automatically detected for each print job, there is a risk that a sheet type different from the sheet type expected by the user will be falsely detected.

[0177] For example, the sheet type can be automatically detected with high accuracy for thin paper, regular paper, and thick paper, but the accuracy of automatically detecting the sheet type for recycled paper and coated paper is not necessarily high.

[0178] In contrast to this, if the auto-reset function is used to prohibit the sheet type setting mode from being restored to the default setting until the execution of a subsequent print job accepted during the execution of a print job is completed, as described above, the user's designation regarding the sheet type of the recording sheet used in the first executed print job will also be applied to the subsequent print job.

[0179] Therefore, it is possible to avoid a problem caused by erroneous detection of the sheet type, i.e., the execution of the print job being stopped due to a mismatch between the sheet type specified in the print job and the erroneously detected sheet type. (1-6) Auto reset setting The auto-reset time may be set at the time of shipping the image forming apparatus 1, or may be set by an administrator or user of the image forming apparatus 1.

[0180] As shown in FIG. 10(a), the "Reset Settings" screen 1000, which is displayed from the "Settings Menu" screen via the "User Settings" screen and the "Environment Settings" screen, has buttons 1001 and 1002 for displaying the "01 Auto Reset Settings" screen and the "02 Mode Reset Settings" screen.

[0181] When button 1001 is selected, an "Auto Reset Setting" screen 1010 is displayed, as shown in Fig. 10(b) . The "Auto Reset Setting" screen 1010 is provided with an "OFF" button and buttons 1011 ranging from "1 minute" to "9 minutes."

[0182] If you select the "OFF" button, the auto reset function will not operate. Also, if you select one of the "1 minute" to "9 minutes" buttons, the auto reset time will be set to the time corresponding to the selected button. For example, if you select the "3 minutes" button, the auto reset function will operate 3 minutes after the print job has completed. (1-6-1) Automatic reset of the operation screen As described above, in addition to when the image forming device 1 does not execute a print job for the auto-reset time, the auto-reset function may also be activated when the user does not operate any screen on the operation panel 161 for the auto-reset time.

[0183] For example, if there is no user operation for the auto-reset time for each of the copy screen, fax / scan screen, fax screen, box screen, and web browser screen, the auto-reset function may be activated to invalidate the user operation accepted on that screen and return (initialize) it to the default settings.

[0184] The copy screen is a screen for receiving instructions for a copy process in which an image is formed in the image forming unit 100 using image data generated by reading an original document in the original document reading unit 151. The fax / scan screen is a screen for receiving instructions for a fax / scan process in which the image data generated by reading an original document in the original document reading unit 151 is transmitted by facsimile in the control unit 101.

[0185] The fax screen is a screen for receiving instructions for fax processing to send a facsimile using facsimile data stored in the control unit 101 without reading a new document with the document reading unit 151. The box screen is a screen for receiving instructions regarding the box function to store data such as image data in the control unit 101 and to read out the stored data.

[0186] The web browser screen can be used to (a) display and print web content on the Internet or an intranet, (b) print, display, and save files on the Internet or an intranet, and (c) upload scanned manuscript data to a server on the Internet or an intranet.

[0187] Furthermore, (d) files in the box can be uploaded to a server on the Internet or an intranet, (e) files in a box on a multifunction device on the network can be used, and (f) user-specific web browser settings can be used. For example, the web browser settings can be restored to the default settings using an auto-reset function.

[0188] On copy screen 1020 as shown in FIG. 10(c), settings such as whether the original is single-sided or double-sided, whether single-sided or double-sided printing is selected, and whether aggregate printing such as 2-in-1 printing is selected are performed. However, if there is no user operation for the auto-reset time after that, all items set by the user on copy screen 1020 until the auto-reset function is activated are initialized to the default settings.

[0189] Furthermore, the auto-reset time for such screen operations may be set for each screen. On copy screen 1020 shown in Fig. 10(c), the auto-reset time may be set by first displaying the "Settings Menu" screen by selecting button 1021, and then displaying the "Auto-reset Settings" screen shown in Fig. 10(b). (1-6-2) Reset by user operation The reset operation may also be initiated by a user operation.

[0190] For example, as shown in Fig. 11(a), when it is detected that a user has placed a stack of documents D on document tray 153 of automatic document feeder 152 in order to copy documents, the setting mode for the sheet type of recording sheets to be used for copying may be reset to the default setting. In this way, when copying, the sheet type of the first recording sheet can be automatically detected and the image process conditions can be set.

[0191] An actuator 1101 protrudes from below the document placement surface of the document tray 153. When a document stack D is placed on the document tray 153 and the document stack D presses down on the actuator 1101, it is detected that the document stack D has been placed on the document tray 153. Note that the sensor that detects that the document stack D has been placed is not limited to a mechanical sensor using the actuator 1101, and other types of sensors such as an optical sensor may also be used.

[0192] Also, as shown in FIG. 11(b), if the image forming device 1 is equipped with a card authentication device 1111, card authentication is performed using an authentication card 1112, and if the card authentication is successful, it is confirmed whether the user whose card authentication has been successful this time is a different user from the user whose card authentication has been successful the previous time.

[0193] If the check shows that the user who successfully authenticated the card is different from the previous one, it is considered unnecessary to apply the sheet type specified by the previous user, and the sheet type setting mode may be reset to the default setting. Conversely, if the user is the same between the previous and current ones, the sheet type setting mode may be maintained as it was last time.

[0194] In this case, the change of user of the image forming apparatus 1 may be detected by using authentication means other than card authentication or by using detection means other than authentication means. Such detection means may include, for example, face recognition to identify a user standing in front of the image forming apparatus 1.

[0195] 11(c), the sheet type setting mode may be reset to the default setting when the user selects a reset key 1121 displayed on the operation panel 161 of the image forming apparatus 1. User settings other than the sheet type setting mode may also be reset to the default setting.

[0196] 11(d), a sleep time 1131 for transitioning the operation mode of the image forming apparatus 1 to the sleep mode can be set using the operation panel 161. In FIG. 11(d), the sleep time 1131 is set to 30 minutes.

[0197] The sleep mode is an operating mode in which power consumption in the image forming apparatus 1 is suppressed other than the power required for the operation of the control unit 101, such as the power required for heating and increasing the temperature of the fixing roller 130. The reason for maintaining the power consumption required for the operation of the control unit 101 is to allow the image forming apparatus 1 to accept operations by the user.

[0198] Therefore, if the sleep time has elapsed without the user operating the image forming apparatus 1, various user settings are reset to their default settings. The initial value of the sleep time may be, for example, one minute, and settings between one minute and 60 minutes may be accepted. Also, a setting to turn off the sleep setting may be accepted so that the operating mode of the image forming apparatus 1 does not transition to sleep mode.

[0199] When the image forming apparatus 1 returns from the sleep mode, the image forming apparatus 1 may reset the sheet type setting mode to the default mode. In this case, the user settings other than the sheet type setting mode may also be reset to the default settings. [2] Second embodiment In this embodiment, whether or not to prohibit the sheet type setting mode from being returned to the default setting by auto-resetting is determined based on whether or not the user has specified "unacceptable letter," a sheet type that is difficult to automatically detect with high accuracy.

[0200] When "unacceptable letters" is not specified by the user, even if the sheet type setting mode is switched to the automatic detection mode by auto-resetting, the sheet type is less likely to be erroneously detected, so that it is possible to avoid problems that may occur when the sheet type of the recording sheet specified in the print job does not match the sheet type of the automatically detected recording sheet.

[0201] Specifically, steps S1201 to S1203 are provided as shown in Fig. 12(a) instead of step S511 in the flowchart shown in Fig. 5. That is, when the auto-reset time has elapsed after a reason for interrupting the image forming process, such as paper empty, toner empty, or waste toner full, occurs (S510: YES), it is checked in the user specification mode whether the sheet type of the recording sheet specified by the user is unacceptable paper.

[0202] As shown in Figure 12(b), recycled paper and coated paper have distinctive reflectance characteristics (surface shape) and light transmittance characteristics, making it difficult to optically detect the sheet type, and therefore are unsuitable letters. On the other hand, the sheet types of thin paper, plain paper, thick paper 1, thick paper 2, thick paper 3, and thick paper 4 can be detected automatically with high accuracy, so they are not unsuitable letters.

[0203] In addition, if automatic detection of unacceptable paper such as recycled paper or coated paper results in a false detection of a sheet type that is not unacceptable paper, the sheet type that may result in this detection may also be determined to be unacceptable paper.

[0204] If the sheet type of the recording sheet specified by the user is unacceptable paper (S1201: YES), if the sheet type setting mode is returned to the default setting (automatic detection mode), there is a risk that the sheet type of the recording sheet will be incorrectly detected when the print job is subsequently resumed.

[0205] In contrast, in this embodiment, the sheet type setting mode is maintained in the user-specified mode (S1202), and therefore unacceptable letters are not automatically detected, thereby avoiding problems that may arise from erroneous detection.

[0206] On the other hand, if the sheet type of the recording sheet specified by the user is not unacceptable letter (S1201: NO), the sheet type setting mode is returned to the default setting (automatic detection mode) (S1203). If the recording sheet is not unacceptable letter, there is no risk of erroneous detection even if the sheet type of the recording sheet is automatically detected. Therefore, if auto-reset is performed as usual, the original effect of the auto-reset function can be obtained. [3] Third embodiment In this embodiment, whether or not to prohibit the sheet type setting mode from being returned to the default setting by auto-resetting is determined based on whether or not a "rejected letter" has been automatically detected, which is difficult to automatically detect accurately as a sheet type.

[0207] When the automatically detected sheet type is not "unacceptable letter", even if the sheet type setting mode is switched to the automatic detection mode by automatic resetting, the sheet type is less likely to be erroneously detected, so that it is possible to avoid problems that may occur when the sheet type of the recording sheet designated in the print job does not match the sheet type of the automatically detected recording sheet.

[0208] Specifically, in the flowchart shown in FIG. 5, when the sheet type of the recording sheet is specified by the user, following step S505, the sheet type of the first recording sheet when executing the print job is automatically detected (S1301), as shown in FIG. 13.

[0209] Thereafter, when the auto-reset time has elapsed since the occurrence of the interruption event of the image forming process (S510: YES), it is confirmed whether the sheet type of the recording sheet automatically detected in step S1301 is unacceptable paper.

[0210] If the sheet type of the automatically detected recording sheet is unacceptable paper (S1302: YES), if the sheet type setting mode is returned to the default setting (automatic detection mode), there is a risk that the sheet type of the recording sheet will be incorrectly detected when the print job is subsequently resumed.

[0211] In contrast, in this embodiment, the sheet type setting mode is maintained in the user-specified mode (S1303), and therefore unacceptable letters are not automatically detected, thereby avoiding problems that may arise from erroneous detection.

[0212] On the other hand, if the automatically detected sheet type of the recording sheet is not unacceptable letter (S1302: NO), the sheet type setting mode is returned to the default setting (automatic detection mode) (S1304). If the recording sheet is not unacceptable letter, there is no risk of erroneous detection even if the sheet type of the recording sheet is automatically detected. Therefore, if an auto-reset is performed as usual, the intended effect of the auto-reset function can be obtained. [4] Variation The present disclosure has been described above based on the embodiments, but it goes without saying that the present disclosure is not limited to the above-described embodiments, and the following modified examples can be implemented. (4-1) In the above embodiment, the case where the default setting of the sheet type setting mode is the automatic detection mode has been described as an example. However, it goes without saying that the present disclosure is not limited to this, and instead of the automatic detection mode, the user-specified mode may be set as the default setting of the sheet type setting mode. (4-2) In the above embodiment, the auto-reset function is used to return the sheet type setting mode to the default setting. However, it goes without saying that the present disclosure is not limited to this, and the following may be used instead.

[0213] For example, a default value for the sheet type may be set in advance, and the sheet type setting may be restored to the default value once the auto-reset time has elapsed since the execution of the print job was interrupted or completed.

[0214] This default value for the sheet type may be set at the time of shipping the image forming apparatus 1, or may be set by an administrator of the image forming apparatus 1. This modified example is particularly effective when recording sheets of sheet types outside the range of sheet types assumed in advance in the specifications of the image forming apparatus 1, such as the above-mentioned "thin paper," "plain paper," "plain paper+," and "thick paper 1" to "thick paper 4," are often used in image formation processes, because it is difficult to correctly and automatically determine the sheet type of the recording sheets even if the sheet type setting mode is switched from the user-specified mode to the automatic detection mode. (4-3) In the above embodiment, the case where the basis weight, which is a characteristic quantity of a recording sheet, is detected by detecting the transmittance of infrared light IR and blue light B and the reflectance of green light G using the media detection sensor 120 has been described as an example, but it goes without saying that the present disclosure is not limited to this, and other types of sensors may be used as the media detection sensor 120. For example, a characteristic quantity for determining the sheet type of a recording sheet can also be obtained by irradiating the recording sheet with ultrasonic waves and detecting the attenuation rate of the intensity. (4-4) In the above embodiment, an example was given in which a message to that effect was displayed on the operation panel 161 when switching the sheet type setting mode. However, it goes without saying that the present disclosure is not limited to this, and instead of or in addition to this, the following may be used.

[0215] For example, the screen that displays the message to switch the sheet type setting mode does not have to be the sheet type setting screen 400, and the message may be displayed regardless of the screen displayed on the operation panel 161.

[0216] Furthermore, instead of displaying a message on operation panel 161, or in addition to displaying the message on operation panel 161, the message may be output as audio. If the message is only displayed on operation panel 161, there is a risk that the user of image forming apparatus 1 will not notice the message. In contrast, if the message is output as audio, it is easier to attract the user's attention compared to when only a screen display is executed.

[0217] Since the user of image forming apparatus 1 does not always pay close attention to touch panel 400 of operation panel 161, if the user does not notice the message, it may take time and effort to realize why the image formation process has been interrupted, especially when a confirmation input is required from the user. On the other hand, if the message is output as audio, the user will be more likely to notice the message, improving user convenience. (4-5) In the above embodiment, an example was given of setting image process conditions according to the sheet type set in two setting modes, the automatic detection mode and the user-specified mode. However, it goes without saying that the present disclosure is not limited to this, and the following may be used instead.

[0218] For example, there are image forming devices that have the function of automatically detecting the sheet type but do not allow the user to specify the sheet type. In such image forming devices, two setting modes can be used: a first setting mode that sets image process conditions according to the automatically detected sheet type, and a second setting mode that sets image process conditions regardless of the sheet type.

[0219] If such an image forming device is equipped with an auto-reset function and the setting mode is returned to the default setting after a period in which no print job is executed continues for a predetermined auto-reset time, it is conceivable that after execution of a print job has started in the first setting mode, a reason for interrupting the print job occurs, causing the print job to be interrupted, and the setting mode for the image process conditions to be returned to the default setting before the print job is resumed.

[0220] When a print job is being executed with image process conditions set according to the automatically detected sheet type, if the image process condition setting mode is restored to the default setting, the image process conditions may no longer be appropriate.

[0221] To address this problem, similarly to the above embodiment, by prohibiting auto-reset, it is possible to maintain the image processing conditions that have been appropriately set, thereby preventing a deterioration in image quality.

[0222] For example, if auto-reset is prohibited on the condition that the execution of a print job is interrupted, an image can be formed under appropriate image process conditions even after the execution of the print job is resumed after the auto-reset time has elapsed since the execution of the print job was interrupted. (4-6) In the above embodiment, the image forming apparatus is described as a tandem color multifunction printer. However, the present disclosure is not limited to this, and the image forming apparatus may be a color multifunction printer or a monochrome multifunction printer of a type other than the tandem type.

[0223] Furthermore, the same effect can be obtained by applying the present disclosure to single-function machines such as a printer device, a copy device in which a scanner is added to a printer device, or a facsimile device in which a facsimile communication function is further added. (4-7) The present disclosure may be a sheet type setting method realized by the processing performed by the above-described image forming apparatus 1. The present disclosure may also be a sheet type setting program realized by a processor such as a CPU executing these methods, or may be a digital signal comprising this sheet type setting program.

[0224] The present disclosure may also be the sheet type setting program or the digital signal recorded on a computer-readable recording medium. Examples of computer-readable recording media include flexible disks, hard disks, CD-ROMs, MOs, DVDs, DVD-ROMs, DVD-RAMs, Blu-ray (registered trademark) discs, and semiconductor memories. The present disclosure may also be the digital signal recorded on these recording media.

[0225] Furthermore, in the present disclosure, the sheet type setting program or the digital signal may be transmitted via a telecommunications line, a wireless or wired communication line, a network such as the Internet, data broadcasting, or the like.

[0226] The present disclosure may also be a computer system having a microprocessor and a memory, wherein the memory stores the sheet type setting program, and the microprocessor operates in accordance with the sheet type setting program. The sheet type setting program or the digital signal may also be recorded on the recording medium and transferred, or the program or the digital signal may be transferred via the network or the like, so that the program or the digital signal can be implemented by another independent computer system. (4-8) The above-described embodiments and modifications may be combined with each other.

[0227] Furthermore, all of the numerical values ​​used above are merely examples for specifically explaining the present disclosure, and the present disclosure is not limited to the numerical values ​​exemplified.

[0228] The division of functional blocks in the block diagram is an example, and multiple functional blocks may be realized as a single functional block, one functional block may be divided into multiple blocks, or some functions may be moved to another functional block.Furthermore, the functions of multiple functional blocks having similar functions may be processed in parallel or time-shared by a single piece of hardware or software.

[0229] The order in which the steps are performed is merely an example for specifically explaining the present disclosure, and other orders may be used. Some of the steps may be performed simultaneously (in parallel) with other steps.

[0230] Furthermore, various modifications of the present embodiment that are within the scope of what would occur to a person skilled in the art are also included in the present disclosure, as long as they do not deviate from the gist of the present disclosure. [Industrial Applicability]

[0231] The image forming apparatus according to the present disclosure is useful as an apparatus that can appropriately set the sheet type of recording sheets by switching the setting mode for the sheet type. [Explanation of symbols]

[0232] 1. Image forming device 100: Image forming unit 101...Control unit 120...Media detection sensor 140...Paper feed cabinet section 151...Image reading unit 152...Automatic document transport unit 161...Operation panel 171……Paper feed section 305...Timer 400..."Manual Feed - Paper Size / Type" screen 406...slide switch 410...Checkbox 600...Automatic paper type detection setting screen 1000...Auto reset setting selection screen 1010...Auto reset time setting screen

Claims

1. An image forming apparatus having a media detection means for automatically detecting a sheet type and a user specification means for accepting a user specification of a sheet type, and set by default to either an automatic detection mode in which priority is given to automatic detection or a user specification mode in which priority is given to user specification, a setting mode receiving means for receiving a setting mode designation; resetting means for changing the setting mode from a designated setting mode to a default setting when a predetermined reset condition is satisfied; and prohibition means for prohibiting the reset means from changing the setting mode and maintaining the designated setting mode, provided that a predetermined prohibition condition is satisfied. An image forming apparatus characterized by:

2. When the setting mode is switched, a switching notification means is provided to notify the fact.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

3. The reset means changes the setting mode to the automatic detection mode when a reset condition is satisfied in a case where the default setting mode is the automatic detection mode and the specified setting mode is the user-specified mode.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

4. The prohibiting means prohibits the resetting means from changing the setting mode when the default setting mode is the automatic detection mode and the specified setting mode is the automatic detection mode as a prohibiting condition.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

5. The factory default setting is either Auto-Detect or User-Specified.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

6. The reset means changes the setting mode on the condition that the device is in a standby state or is not accepting a print job.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

7. The resetting means determines that a predetermined auto-reset time has elapsed while no print job is being executed as a resetting condition.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

8. The prohibiting means prohibits the resetting means from changing the setting mode when the execution of the print job is interrupted as a prohibiting condition.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

9. If the reset condition is satisfied while the execution of the print job is suspended, the prohibition means prohibits the change of the setting mode until the execution of a subsequent print job that has been accepted until the execution of the print job is completed is completed.

9. The image forming apparatus according to claim 8, wherein the image forming apparatus is a recording medium.

10. an interruption reason detection means for detecting an interruption reason for interrupting execution of a print job, such as paper empty, toner empty, or waste toner full; and a job interruption means for interrupting execution of a print job when a reason for interruption is detected.

10. The image forming apparatus according to claim 8, wherein the image forming apparatus is a recording medium.

11. a user operation receiving means for displaying an operation screen relating to copy, fax / scan, fax, box or web browser and receiving a user operation; and a screen operation reset means for invalidating user operations accepted on the operation screen after the operation screen is displayed, on the condition that no user operations are accepted for a predetermined time while the operation screen is being displayed.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

12. a reset instruction receiving means for receiving a reset instruction from a user; The resetting means sets the resetting condition as receiving a reset instruction from the user.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

13. reading means for reading an original; a document transport means for transporting documents one by one from a stack of documents placed on a document tray to the reading means, The document transport means has a document detection means for detecting that a document stack has been placed on the document tray, The resetting means sets a reset condition when a stack of documents is placed on the document tray.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

14. A user authentication means is provided for performing user authentication, The resetting method is performed when a new user authentication is performed.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

15. The reset means performs the change when the operation mode of the device returns from the sleep mode as a reset condition.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

16. The prohibition means sets a prohibition condition that, when the setting mode accepted by the setting mode acceptance means is a user-specified mode, the sheet type accepted as specified by the user is an unacceptable sheet type that is likely to be erroneously detected by the media detection means.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

17. The prohibition means automatically detects the sheet type when the setting mode accepted by the setting mode acceptance means is the user-specified mode, and sets the automatically detected sheet type as an unacceptable sheet type that is likely to be erroneously detected by the media detection means as a prohibition condition.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

18. When the reset means switches the setting mode from the user-specified mode to the automatic detection mode, the sheet type is automatically detected for the first recording sheet of the next print job to be executed.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

19. When the resetting means prohibits the setting mode from being switched from the user-specified mode to the automatic detection mode, the prohibiting means maintains the setting mode in the user-specified mode until the sheet type is automatically detected for the first recording sheet of the next print job to be executed.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

20. a paper feed cassette that can be opened and closed to supply recording sheets for printing; When the reset means switches the setting mode from the user-specified mode to the automatic detection mode, the sheet type is automatically detected by the first recording sheet supplied from the paper feed cassette after the paper feed cassette is opened and closed next time.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

21. a paper feed cassette that can be opened and closed to supply recording sheets for printing; When the prohibiting means prohibits the resetting means from switching the setting mode from the user-specified mode to the automatic detection mode, the setting mode is maintained in the user-specified mode until the sheet type is automatically detected for the first recording sheet fed from the paper feed cassette after the paper feed cassette is opened and closed next time.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

22. The reset means changes the setting mode from the specified setting mode to the default setting on the condition that the execution of the print job being executed when the reset condition is satisfied has been completed, and further on the condition that if a subsequent print job is accepted during the execution of the print job, the execution of the subsequent print job has been completed.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

23. When the prohibiting means prohibits the resetting means from switching the setting mode from the user-specified mode to the automatic detection mode, the setting mode is maintained in the user-specified mode until the execution of the print job being executed when the resetting condition is satisfied is completed, and further, if a subsequent print job is accepted during the execution of the print job, until the execution of the subsequent print job is completed.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

24. The setting mode accepting means can accept designation of the setting mode with administrator authority and user authority, If the automatic detection mode is specified with administrator privileges, the setting mode can be changed to user-specified mode with user privileges. If the user-specified mode is specified with administrator privileges, changing the setting mode to auto-detection mode with user privileges is prohibited.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

25. The media detection means uses an optical sensor to measure at least one of the transmittance and reflectance of the recording sheet, thereby determining the sheet type.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

26. If the setting mode is automatic detection mode, the print job is executed under the image processing conditions according to the automatically detected sheet type, If the setting mode is user-specified mode, the print job is executed under image processing conditions according to the sheet type specified by the user.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

27. An image forming apparatus having a media detection means for automatically detecting a sheet type, and a setting mode for determining whether or not to set image process conditions according to the automatically detected sheet type is set as a default, a setting mode receiving means for receiving a setting mode designation; resetting means for changing the setting mode from a designated setting mode to a default setting when a predetermined reset condition is satisfied; and prohibition means for prohibiting the reset means from changing the setting mode and maintaining the designated setting mode, provided that a predetermined prohibition condition is satisfied. An image forming apparatus characterized by:

28. A sheet type setting method executed by an image forming apparatus having a media detection means for automatically detecting a sheet type and a user specification means for accepting a user specification of a sheet type, the image forming apparatus being set by default to either an automatic detection mode that prioritizes automatic detection or a user specification mode that prioritizes user specification, the method comprising: a setting mode receiving step of receiving a setting mode designation; a reset step for changing the configuration mode from the specified configuration mode to a default configuration when a predetermined reset condition is met; and an inhibiting step of inhibiting the reset means from changing the setting mode and maintaining the designated setting mode, provided that a predetermined inhibiting condition is satisfied. A sheet type setting method comprising:

29. A sheet type setting program executed by a computer installed in an image forming apparatus having a media detection means for automatically detecting a sheet type and a user specification means for accepting a user specification of a sheet type, the image forming apparatus being set by default to either an automatic detection mode that prioritizes automatic detection or a user specification mode that prioritizes user specification, a setting mode receiving step of receiving a setting mode designation; a reset step for changing the configuration mode from the specified configuration mode to a default configuration when a predetermined reset condition is met; and an inhibiting step of inhibiting the change of the setting mode by the resetting means and maintaining the designated setting mode, on condition that a predetermined inhibiting condition is satisfied. A sheet type setting program comprising:

Images