Image formation device, control method, and program

Abstract

To provide an image formation device that can reduce the number of measurement instruction operations for a media sensor by a user and can reduce workload of the user, a control method, and a program.SOLUTION: An image formation device 100 comprises: a plurality of sheet storage means for storing sheets; a transportation part that transports the sheet fed from each sheet storage means; an image formation part which forms an image on the sheet; a media sensor which measures physical properties of the sheet; and an operation part comprising a touch panel and a display. When executing sheet kind discrimination on the basis of the physical properties measured by the media sensor in the image formation device 100, a first screen for collectively selecting two or more sheet storage means as an object of sheet kind discrimination is displayed on the operation part, and when two or more sheet storage means are selected by a user via the operation part, sheet kind discrimination is continuously executed for each of the two or more sheet storage means.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to an image forming apparatus, a control method, and a program, and more particularly to an image forming apparatus, a control method, and a program including a sensor for measuring physical property values of a sheet.

Background Art

[0002] In recent years, some electrophotographic image forming apparatuses include a sensor (hereinafter referred to as a media sensor) for measuring physical property values of a sheet in order to discriminate the type of the sheet as a printing medium. The media sensor measures the physical property values of the sheet using an optical sensor, an ultrasonic sensor, or the like, and notifies the measurement result to a controller of the image forming apparatus. The controller extracts sheet information that matches the measurement value from the pre-registered sheet information, and discriminates the sheet type to display candidates for the sheet type based on the extracted sheet information. The user selects the sheet type to be set for printing from the displayed candidates. The controller sets image forming conditions according to the sheet type selected by the user and performs printing. Thereby, a good printed matter can be obtained under image forming conditions suitable for the characteristics of the sheet.

[0003] Patent Document 1 proposes a method of displaying candidates for the sheet type based on the measurement result of the media sensor each time printing is executed, and the user selects the sheet type to be set for printing from the displayed candidates.

[0004] In addition to this, a configuration having a sheet type discrimination mode for executing sheet type discrimination based on the measurement result of the media sensor independently of the printing operation is known. In such a configuration, by executing the sheet type discrimination mode in advance to set the sheet type to be printed, printing can be performed without taking the trouble of setting at the time of printing.

[0005] It is common for an image forming apparatus to have a plurality of paper feed cassettes for storing sheets, and since different types of sheets may be stored in each paper feed cassette, the setting of the sheet type is usually performed for each paper feed cassette.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0007] However, when different types of sheets are stored in a plurality of paper feed cassettes, in order to determine the sheet type for each paper feed cassette, the measurement instruction operation for the media sensor has to be repeated as many times as the number of paper feed cassettes. Such an operation with low convenience has the problem of a large work load on the user.

[0008] An object of the present invention is to provide an image forming apparatus, a control method, and a program that can reduce the number of measurement instruction operations for a media sensor by a user and reduce the work load on the user.

Means for Solving the Problems

[0009] In order to solve the above problems, an image forming apparatus according to claim 1 of the present invention includes a plurality of sheet storage means for storing sheets, a conveyance means for conveying the sheets fed from each of the plurality of sheet storage means along a conveyance path, an image forming means for forming an image on the sheets conveyed by the conveyance means, a measurement means provided in the conveyance path for measuring physical property values of the sheets conveyed through the conveyance path, and a user interface having an input interface and an output interface. The image forming apparatus is characterized in that it includes a control means for executing a sheet type determination for determining a sheet type of the sheets based on the physical property values measured by the measurement means. The control means displays a first screen for collectively selecting two or more of the plurality of sheet storage means as objects of the sheet type determination on the output interface, and when the two or more sheet storage means are selected by the user via the input interface, continuously executes the sheet type determination for each of the two or more sheet storage means.

Effect of the Invention

[0010] According to the present invention, the number of measurement instruction operations by the user for the media sensor can be reduced, and the work load of the user can be reduced.

Brief Description of the Drawings

[0011]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Embodiments for Carrying Out the Invention

[0012] Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. However, the components described in this embodiment are merely examples, and are not intended to limit the scope of the present invention only thereto.

[0013] (Example 1) FIG. 1 is a cross-sectional view showing a schematic configuration of an image forming apparatus 100 according to an embodiment of the present invention. The image forming apparatus 100 is a tandem type - intermediate transfer type laser beam printer using an electrophotographic process.

[0014] In FIG. 1, the image forming apparatus 100 is constituted by an image forming apparatus main body 100A and is communicably connected to an image reading apparatus 101.

[0015] The image forming apparatus main body 100A has an operation unit 102 and a manual feed unit 135 on the outside. Further, an image forming unit 100B, a primary transfer unit 100C, a conveyance unit 100D, a secondary transfer unit 100E, a fixing unit 100F, a duplex reversing unit 100G, sheet feeding devices 131 to 134, and a media sensor 210 are provided inside thereof.

[0016] The image forming unit 100B (image forming means) forms an image on the sheet P. The primary transfer unit 100C transfers the toner image on the photosensitive drum 112 to the transfer belt 116. The conveyance unit 100D (conveyance means) includes various rollers and a conveyance path, and conveys the sheet P with the rollers along the conveyance path. The secondary transfer unit 100E transfers the toner image on the transfer belt 116 to the sheet. The fixing unit 100F includes a pressure roller 121a and a heating roller 121b, and heats and presses the sheet P with these rollers to fix the toner image. The duplex reversing unit 100G reverses the sheet P for duplex printing.

[0017] The image reading device 101 is installed substantially horizontally above the image forming apparatus main body 100A, and a discharge space S for sheet discharge is formed between the image reading device 101 and the image forming apparatus main body 100A. A stacking unit 123 for stacking the sheet P with an image fixed on one side or both sides is provided in the discharge space S.

[0018] The sheet feeding devices 131 to 134 each have a paper feed cassette 131a to 134a which is a sheet storage means for storing the sheet P, and feed the sheet P from each of the paper feed cassettes 131a to 134a. The sheet feeding device 131 includes a pickup roller 136 (sheet feeding means) and a separating unit including a feed roller 137 and a retard roller 138 for separating the sheet P fed out from the pickup roller 136. In the vicinity of the sheet feeding device 131, a cassette 1 opening / closing detection sensor 221 (not shown in FIG. 1) which will be described in detail with reference to FIG. 2 is provided. The sheet feeding devices 132 to 134 have the same configuration as the sheet feeding device 131.

[0019] The manual feed unit 135 has a manual paper feed tray 135a which is a sheet storage means for storing the sheet P, and feeds the sheet P from the manual paper feed tray 135a. Also, similar to the sheet feeding devices 131 to 134, the manual feed unit 135 includes a pickup roller 139 (sheet feeding means) and a separating unit including a feed roller 140 and a retard roller 141 for separating the sheet P sent out from the pickup roller 139. Near the manual feed unit 135, a tray presence / absence detection sensor 225 (not shown in FIG. 1), which will be described in detail with reference to FIG. 2, is provided. Although only one tray (manual paper feed tray 135a) is provided in the manual feed unit 135, a plurality of trays having a similar configuration may be provided.

[0020] The media sensor 210 (measuring means) is provided in the conveyance path downstream of the sheet feeding devices 131 to 134 and measures the physical property values of the sheet P.

[0021] The image forming unit 100B (image forming means) is of a four-drum full-color type and includes a laser scanner 110 and four process cartridges 111. Each process cartridge 111 includes a photosensitive drum 112, a charger 113 which is a charging means, and a developing device 114 which is a developing means, and forms toner images of different colors (yellow (Y), magenta (M), cyan (C), and black (K)).

[0022] The image forming unit 100B includes a secondary transfer unit 100E arranged above the process cartridge 111 and a fixing unit 100F in the conveyance path downstream of the four process cartridges 111. Also, the image forming unit 100B includes a toner cartridge 115 for supplying toner to the developing device 114.

[0023] The secondary transfer unit 100E includes a transfer belt 116 wound around a drive roller 116a and a tension roller 116b. Inside the transfer belt 116, a primary transfer roller 116c that contacts the transfer belt 116 at a position facing the photosensitive drum 112 is provided for each color. The transfer belt 116 is rotated in the direction of the arrow by a drive roller 116a driven by a drive unit (not shown). At a position facing the drive roller 116a of the secondary transfer unit 100E, a secondary transfer roller 120 for transferring the color image formed on the transfer belt 116 to the sheet P is provided. A fixing unit 100F is arranged above this secondary transfer roller 120, and above (downstream) the fixing unit 100F, a first discharge roller pair 122a and a second discharge roller pair 122b, which are part of the conveyance unit 100D, and a duplex reversing unit 100G are arranged.

[0024] The duplex reversing unit 100G is provided with a pair of reversing rollers 124 that can rotate forward and backward and a re-conveyance path R for re-conveying the sheet P with an image formed on one side back to the image forming unit 100B.

[0025] The first discharge roller pair 122a and the second discharge roller pair 122b discharge the sheet P with an image formed on one side or both sides into the discharge space S.

[0026] The operation unit 102 is located on the upper part of the image forming apparatus main body 100A and receives operations from the user.

[0027] Next, the image forming operation of the image forming apparatus 100 will be described. The image forming apparatus 100 processes the image data of the document to be printed, converts it into an electrical signal, and transmits it to the laser scanner 110 of the image forming unit 100B. In the image forming unit 100B, the surface of the photosensitive drum 112 uniformly charged to a predetermined polarity and potential by the charger 113 is sequentially exposed by the laser of the laser scanner 110. As a result, electrostatic latent images of yellow, magenta, cyan, and black are sequentially formed on the photosensitive drums 112 of the respective process cartridges 111.

[0028] The electrostatic latent image is developed and visualized with each color toner by the developing device 114, and the color toner images on each photoreceptor drum 112 are sequentially superimposed and transferred onto the transfer belt 116 by the primary transfer bias applied to the primary transfer roller 116c. Thereby, a toner image is formed on the transfer belt 116. In parallel with the toner image forming operation, the sheet P is conveyed by the conveying unit 100D. The sheet P is conveyed one by one to the registration roller pair 130 by the sheet feeding devices 131 to 134 or the manual feeding unit 135, and the skew of the sheet P is corrected by the registration roller pair 130. Subsequently, the sheet P is conveyed to the secondary transfer unit 100E by the registration roller pair 130, and in the secondary transfer unit 100E, the toner image is collectively transferred onto the sheet P by the secondary transfer bias applied to the secondary transfer roller 120. Thereafter, the sheet P is conveyed to the fixing unit 100F, and heat and pressure are applied in the roller nip portion formed by the pressure roller 121a and the heating roller 121b to melt and mix the toners of each color, thereby fixing a color image on the sheet P. The sheet P on which the image is fixed is discharged into the discharge space S by the first discharge roller pair 122a and the second discharge roller pair 122b provided downstream of the fixing unit 100F, and the image forming operation is completed by stacking it on the stacking unit 123 provided on the bottom surface of the discharge space S. When forming images on both sides of the sheet P, after the image is fixed on the front surface of the sheet P, the sheet P is conveyed to the re-conveying passage R by the reversing roller pair 124 and conveyed to the image forming unit 100B again with its back surface reversed. Thereafter, in the same manner as the image fixing on the front surface, after the image is fixed on the back surface of the sheet P, the sheet P is discharged into the discharge space S by the first discharge roller pair 122a and the second discharge roller pair 122b and stacked on the stacking unit 123 to complete the image forming operation.

[0029] FIG. 2 is a diagram showing the configuration of a controller 200 that controls the overall operation of the image forming apparatus 100 having the above-described configuration.

[0030] FIG. 2 shows the configuration when the controller 200 controls the media sensor 210 to perform the sheet type discrimination process, and the configuration when performing other controls, for example, the control of the image forming process, is omitted.

[0031] The controller 200 is an information device including a CPU (Central Processing Unit) 201, a ROM (Read Only Memory) 202, and a RAM (Random Access Memory) 203. Connected to the CPU 201 are an operation unit 102, a media sensor 210, a cassette 1 open / close detection sensor 221, a cassette 2 open / close detection sensor 222, a cassette 3 open / close detection sensor 223, a cassette 4 open / close detection sensor 224, and a tray presence / absence detection sensor 225.

[0032] The CPU 201 (control means) performs various processes including a sheet type discrimination process by the image forming apparatus 100 by executing a program stored in the ROM 202. Thereby, the CPU 201 controls each device of the image forming apparatus 100. For example, the CPU 201 forms a full-color image based on image data on the sheet P. Also stored in the ROM 202 is information associating the measurement result of the media sensor 210 with the sheet type. The RAM 203 provides a work area when the CPU 201 performs processing and stores temporary data and the like.

[0033] The operation unit 102 is a user interface including an input interface and an output interface. The input interface includes various key buttons, a touch panel, and the like. The output interface includes a display, a speaker, and the like. The user inputs various instructions and data through the input interface of the operation unit 102. The user can check the state and notifications of the image forming apparatus 100 through various screens and the like displayed on the output interface of the operation unit 102.

[0034] The media sensor 210 is composed of a CPU 211, an ultrasonic sensor 212, and an optical sensor 213. The measurement results of the sheet P by these sensors are used to determine the sheet type of the sheet P. The CPU 211 receives an instruction from the CPU 201 of the controller 200, drives the ultrasonic sensor 212 and the optical sensor 213, and transmits the measurement results of the sheet P by these sensors to the CPU 201. When the CPU 201 receives the measurement results from the media sensor 210, it determines the sheet type of the sheet P based on the information stored in the ROM 202 that associates the received measurement results with the sheet type, and displays it on the operation unit 102. The details of the method for determining the sheet type will be described later.

[0035] The ultrasonic sensor 212 irradiates the sheet P with ultrasonic waves, detects the ultrasonic waves transmitted through the sheet P, and converts them into an output voltage. By detecting the ultrasonic waves transmitted through the sheet P, a value corresponding to the attenuation amount of the ultrasonic waves transmitted through the sheet P can be obtained. The attenuation amount of the ultrasonic waves transmitted through the sheet P changes according to the basis weight of the sheet P, which is a physical property value of the sheet P. For example, if the sheet P is a thick sheet, the attenuation amount when the ultrasonic waves are transmitted is larger than that of a thin sheet. Utilizing this, the basis weight of the sheet P can be measured by the ultrasonic sensor 212.

[0036] The optical sensor 213 is a CIS (Contact Image Sensor). It irradiates the sheet P with light, detects the amount of reflected light, and converts it into an output voltage. The reflected light from the sheet P becomes larger as the reflectance of the surface of the sheet P, which is a physical property value of the sheet P, is higher. For example, when the sheet P is a so-called coated paper in which the paper surface is coated with a coating agent to enhance smoothness and glossiness, the reflectance of the surface of the sheet P is higher than that of uncoated paper. Therefore, the reflected light from the sheet P when irradiated with light is more than that of uncoated paper. Utilizing this, the optical sensor 213 can be used to determine the sheet type according to the surface properties of the sheet P, for example, to determine whether the sheet P is coated paper or uncoated paper.

[0037] The cassette 1 opening / closing detection sensor 221, the cassette 2 opening / closing detection sensor 222, the cassette 3 opening / closing detection sensor 223, and the cassette 4 opening / closing detection sensor 224 (opening / closing detection means) are sensors having the same configuration for detecting the opening and closing of the paper feed cassettes 131a to 134a, respectively. Therefore, hereinafter, only the configuration of the cassette 1 opening / closing detection sensor 221 will be described in detail, and the description of the cassette 2 opening / closing detection sensor 222, the cassette 3 opening / closing detection sensor 223, and the cassette 4 opening / closing detection sensor 224 will be omitted.

[0038] The cassette 1 opening / closing detection sensor 221 and the tray presence / absence detection sensor 225 are optical sensors each having a light emitting part and a light receiving part, and output a signal according to the amount of light received by the light receiving part.

[0039] The cassette 1 opening / closing detection sensor 221 is provided in the vicinity of the paper feed cassette 131a. The paper feed cassette 131a is normally housed in the image forming apparatus 100. This state is generally referred to as the paper feed cassette 131a being closed. While the paper feed cassette 131a is closed, the light of the light emitting part of the cassette 1 opening / closing detection sensor 221 is blocked by a flag provided on the paper feed cassette 131a. At this time, since the light receiving part of the cassette 1 opening / closing detection sensor 221 does not detect light, the output value of the cassette 1 opening / closing detection sensor 221 becomes lower than when it detects light. When the user replenishes the sheet P in the paper feed cassette 131a, the paper feed cassette 131a is pulled out from the image forming apparatus 100. This state is generally referred to as the paper feed cassette 131a being open. In the state where the paper feed cassette 131a is open, the position of the flag is changed as the paper feed cassette 131a moves, and the cassette 1 opening / closing detection sensor 221 is configured to be able to detect the light of the light emitting part with the light receiving part. At this time, the output value of the cassette 1 opening / closing detection sensor 221 becomes higher than when the paper feed cassette 131a is closed. The CPU 201 constantly monitors the output value of the cassette 1 opening / closing detection sensor 221, and can detect the opening and closing of the paper feed cassette 131a by determining whether the monitored output value is higher or lower than a predetermined threshold value.

[0040] The CPU 201 also constantly monitors the output values of the cassette 2 opening / closing detection sensor 222, the cassette 3 opening / closing detection sensor 223, and the cassette 4 opening / closing detection sensor 224, and determines whether each of the monitored output values is higher or lower than a predetermined threshold value. Thereby, the CPU 201 can also detect the opening and closing of the paper feed cassettes 131a to 134a.

[0041] The tray presence / absence detection sensor 225 (sheet presence / absence detection means) is an optical sensor having a function of detecting the sheet P set on the manual paper feed tray 135a, and is provided near the manual paper feed tray 135a. When the sheet P is not set on the manual paper feed tray 135a, the light of the light emitting part of the tray presence / absence detection sensor 225 is blocked by a flag provided on the manual paper feed tray 135a. At this time, since the light receiving part of the tray presence / absence detection sensor 225 does not detect light, the output value of the tray presence / absence detection sensor 225 becomes lower than when it detects light. When the sheet P is set on the manual paper feed tray 135a, the position of the flag is changed by the sheet P pressing down the flag, and the tray presence / absence detection sensor 225 is configured to be able to detect the light of the light emitting part with the light receiving part. At this time, the output value of the tray presence / absence detection sensor 225 becomes higher than when the sheet P is not set. The CPU 201 constantly monitors the tray presence / absence detection sensor 225, and can detect whether the sheet P is set on the manual paper feed tray 135a by determining whether the output value of the monitored output value is higher or lower than a predetermined threshold value. The CPU 201 can detect that the sheet P has been removed from the manual paper feed tray 135a by detecting the change from the state where the sheet P is present on the manual paper feed tray 135a to the state where it is not. Similarly, the CPU 201 can detect that the sheet P has been set on the manual paper feed tray 135a by detecting the change from the state where the sheet P is not present on the manual paper feed tray 135a to the state where it is present.

[0042] FIG. 3 is a diagram for explaining a method of discriminating the type of the sheet P using the media sensor 210 according to the present embodiment.

[0043] The CPU 201 determines the sheet type of the sheet P using the measurement results from the media sensor 210 having two parameters: the ultrasonic reception signal detected by the ultrasonic sensor 212 and the amount of reflected light detected by the optical sensor 213.

[0044] As shown in FIG. 3, a basis weight discrimination threshold A and a basis weight discrimination threshold B are defined for the value of the ultrasonic reception signal, and a surface property discrimination threshold is defined for the value of the amount of reflected light. The CPU 201 determines the magnitude relationship between the measurement result of the ultrasonic sensor 212 and the basis weight discrimination threshold A and the basis weight discrimination threshold B, and the magnitude relationship between the measurement result of the optical sensor 213 and the surface property discrimination threshold. Then, according to this determination result, the CPU 201 specifies the weight of the sheet P (whether it is thin paper, plain paper, or thick paper) and the sheet type (whether it is coated paper or uncoated paper). That is, the CPU 201 uses the measurement results from the media sensor 210 to determine which of the six types of (1) thin paper uncoated, (2) plain paper uncoated, (3) thick paper uncoated, (4) thin paper coated, (5) plain paper coated, and (6) thick paper coated the sheet P is. For example, when the measurement result of the ultrasonic sensor 212 is greater than the basis weight discrimination threshold B and the measurement result of the optical sensor 213 is less than the surface property discrimination threshold, the CPU 201 determines that the sheet type of the sheet P is "(1) thin paper uncoated".

[0045] However, the sheet type of the sheet P determined by the CPU 201 is not limited to the six types described in FIG. 3, and it is also possible for the user to newly add a sheet type. For example, when newly adding a sheet type of plain paper coated, in addition to the originally registered sheet type of plain paper coated, a sheet type named plain paper coated_user defined can be added. Here, the name "user defined" is used to easily distinguish between the originally registered one and the newly defined one by the user, but the name of the sheet type can be arbitrarily changed by the user. The user can newly add a sheet type and adjust the print condition settings to desired values according to the sheet type, thereby making the image forming apparatus 100 have print conditions optimized for the sheet type of the sheet P.

[0046] However, since the plain paper coated_user-defined, which is a newly added sheet type by the user, does not have information on the measured values of the corresponding media sensor 210 in the ROM 202 of the controller 200, it cannot be distinguished from the plain paper coated. When there are a plurality of candidates that cannot be distinguished in this way, the CPU 201 displays the plurality of candidates on the operation unit 102 and sets the sheet type selected by the user. The details of this setting method will be described later.

[0047] FIG. 4 is a flowchart of the sheet type determination process according to the present embodiment. This series of processes is started by the CPU 201 when, in a standby state where the image forming apparatus 100 is not performing an image forming operation, the operation unit 102 instructs the user to execute the sheet type determination mode. Further, this process is executed by the CPU 201 expanding the program stored in the ROM 202 into the RAM 203.

[0048] The CPU 201 displays a paper feed cassette / tray selection screen (first screen) shown in FIG. 5(a) on the operation unit 102, and accepts a setting of the paper feed cassette / tray to be detected from the user through the operation unit 102 (step S101). As shown in FIG. 5(a), the paper feed cassette / tray selection screen displayed on the operation unit 102 has a list of paper feed cassettes and trays that can be selected by the user, a message prompting the selection of the detection target, and a detection execution button for instructing the execution of detection. On the paper feed cassette / tray selection screen, the user can select a plurality of detection targets collectively (in a batch) from the list of paper feed cassettes and trays. By enabling the user to select a plurality of detection targets collectively in this way, compared with a configuration in which sheet type determination is executed every time one detection target is selected by the user, the user can perform the operations of sheet type determination and sheet type registration with a smaller workload.

[0049] When the user selects a paper feed cassette or tray to be detected, the paper feed cassette / tray selection screen displayed on the operation unit 102 transitions from the state of FIG. 5(a) to the state of FIG. 5(b). As shown in FIG. 5(b), the detection targets (here, cassette 1 and cassette 2) selected by the user are highlighted with their colors changed. After that, when the user selects the detection execution button, the CPU 201 causes the media sensor 210 to measure the sheet P fed from the paper feed cassette or tray to be detected. In FIG. 5(b), an example where two paper feed cassettes, cassette 1 and cassette 2, are selected is shown, but the number of selections may be two or more. When there is only one paper feed cassette and tray that the user wants to detect, the user can also select one detection target on the paper feed cassette / tray selection screen of FIG. 5(a).

[0050] Returning to FIG. 4, the CPU 201 determines whether a paper feed cassette / tray to be detected has been selected by the user and a detection execution instruction has been given (the detection execution button has been selected) on the paper feed cassette / tray selection screen (FIG. 5(a)) (step S102). If none of the paper feed cassettes / trays have been selected as a detection target or there is no detection execution instruction (step S102: No), the CPU 201 waits while displaying the paper feed cassette / tray selection screen. On the other hand, when at least one of the paper feed cassettes / trays has been selected as a detection target and a detection execution instruction is received (step S102: Yes), the CPU 201 executes the paper feed of the sheet P from each of the paper feed cassettes / trays to be detected (step S103).

[0051] After that, the CPU 201 measures the sheet P being conveyed by the media sensor 210 (step S104), and discriminates the sheet type of the sheet P based on the measurement result of the media sensor 210 (step S105). The sheet P for which the sheet type has been discriminated in step S105 is discharged to the discharge space S without performing image formation.

[0052] The CPU 201 determines whether it has determined the sheet types of the sheets P fed from all the detected paper feed cassettes / trays selected by the user in step S102 (step S106). As a result of the determination, if the determination of the sheet types of the sheets P fed from all the detected objects has not yet been completed (step S106: No), the process returns to step S103 to perform paper feeding for the paper feed cassette / tray that has not been determined. On the other hand, if the determination of the sheet types of the sheets P for all the detected objects (paper feed cassettes / trays) has been completed (step S106: Yes), the sheet type determination result is displayed on the operation unit 102, and user selection of the sheet types of the sheets P is accepted for each detected object (step S107). The sheet type setting screen (second screen) displayed on the operation unit 102 at this time is shown in Fig. 6(a). On the sheet type setting screen, for each of the detected paper feed cassettes / trays, a list of candidates (sheet type setting candidates) is displayed as the sheet type determination result. Also, on the sheet type setting screen, a message prompting the user to select the sheet type to be set from the list of candidates, and a registration button for registering the sheet type selected by the user are displayed. The display screen of the operation unit 102 when the user selects the sheet type to be set is shown in Fig. 6(b). The color of the sheet type selected by the user has changed and is highlighted. After this, the user can register the selected sheet type by selecting the registration button.

[0053] Returning to Fig. 4, the CPU 201 determines whether the sheet type has been user-selected and a registration instruction has been given (the registration button has been selected) on the sheet type setting screen displayed in step S107 (step S108). If the sheet type has not been selected or there is no registration instruction (step S102: No), it waits while displaying the sheet type setting screen. On the other hand, if the sheet type has been selected and a detection execution instruction is received (step S108: Yes), the selected sheet type is registered in a batch for the detected paper feed cassette (step S109), and after ending the sheet type determination mode, this process ends.

[0054] According to the above embodiment, on the paper feed cassette / tray selection screen, when two or more paper feed cassettes / trays are collectively designated as detection targets, the CPU 201 continuously determines the sheet types of the sheets P fed from each of the designated detection targets. As a result, the number of times the user instructs the image forming apparatus 100 to execute the sheet type determination can be reduced, and the work load of the user can be reduced.

[0055] (Embodiment 2) In Embodiment 1, the case where it is possible to determine the sheet types of the sheets P fed from all the paper feed cassettes / trays that are detection targets has been described. However, when some malfunction occurs in the image forming apparatus 100, it may also happen that the sheet type of the sheet P fed from any of the paper feed cassettes / trays cannot be determined. In this case, there is a problem that it becomes a work load for the user to execute the sheet type determination process from the beginning again. In this embodiment, means for solving such a problem is provided. Here, as a case where the sheet type cannot be determined, a situation is exemplified in which a plurality of sheets P are fed again and the measured value of the ultrasonic sensor 212 of the media sensor 210 becomes extremely low.

[0056] FIG. 7 is a diagram for explaining a method of determining the type of the sheet P using the media sensor 210 according to this embodiment.

[0057] The method of determining the sheet type using the media sensor 210 according to Embodiment 1 described with reference to FIG. 3 is different in that a region where it is impossible to determine is added to the ultrasonic reception signal. Note that a region where it is impossible to determine may also be added to the amount of reflected light.

[0058] When the ultrasonic reception signal (a signal indicating the attenuation amount of ultrasonic waves) falls below the non-determinable discrimination threshold value, the CPU 201 determines that it is impossible to determine with the media sensor 210 and that the sheet type determination is not detected.

[0059] In this embodiment, when there is a paper feed cassette / tray for which sheet type discrimination could not be performed during the execution of the sheet type discrimination process, a configuration will be described in which it is possible to instruct the re-execution of sheet type discrimination only for the undetected paper feed cassette / tray. For an undetected paper feed cassette / tray, the user can easily instruct the re-execution of sheet type discrimination without having to operate the sheet type discrimination process from the beginning, thereby reducing the user's workload.

[0060] Hereinafter, the sheet type discrimination process according to this embodiment, which is different from Embodiment 1 in that it includes an undetected paper feed cassette / tray re-execution process, will be described.

[0061] FIG. 8 is a flowchart of the sheet type discrimination process according to this embodiment. This series of processes is started by the CPU 201 when, in a standby state where the image forming apparatus 100 is not performing an image forming operation, the operation unit 102 instructs the user to execute the sheet type discrimination mode. Also, this process is executed by the CPU 201 expanding the program stored in the ROM 202 into the RAM 203.

[0062] Steps S201 to S204 in FIG. 8 are the same as the processes in steps S101 to S104 in FIG. 4, so the description thereof will be omitted.

[0063] In step S204, the CPU 201 measures the sheet P being conveyed that has been fed from the target cassette / tray by the media sensor 210, and then determines whether the measurement value by the media sensor 210 is normal (step S205). Specifically here, it is determined whether the value of the ultrasonic reception signal, which is the measurement result of the ultrasonic sensor 212 of the media sensor 210, is equal to or less than the non-determinable discrimination threshold. If the value of the ultrasonic reception signal exceeds the non-determinable discrimination threshold, it is determined that the measurement value is normal (step S205: Yes), and the process proceeds to step S206. On the other hand, when the value of the ultrasonic reception signal is equal to or less than the non-determinable discrimination threshold, it is determined that the measurement value is abnormal, and it is stored that the sheet type discrimination of the sheet P fed from the target paper feed cassette / tray is undetected but has been executed.

[0064] In step S206, the CPU 201 determines the sheet type based on the measurement result, stores that the sheet type determination of the target paper feed cassette has been executed, and proceeds to step S207.

[0065] On the other hand, if the value of the ultrasonic reception signal, which is the measurement result of the ultrasonic sensor 212 of the media sensor 210 in step S205, is equal to or less than the non-determinable discrimination threshold (S205: No), the process proceeds to step S208.

[0066] In step S208, the CPU 201 determines that the media sensor 210 could not normally measure the sheet P fed from the target cassette / tray, stores that the sheet type determination of the target paper feed cassette / tray is undetected but has been executed, and proceeds to step S207.

[0067] In step S207, the CPU 201 determines whether the sheet types of the sheets P fed from all the paper feed cassettes / trays to be detected, which were determined to be user-selected in step S102, have been determined. As a result of the determination, if the determination of the sheet types of the sheets P of all the detection targets (paper feed cassettes / trays) has not yet been completed (step S207: No), the process returns to step S203 to execute paper feeding from the paper feed cassette / tray that has not been determined. On the other hand, if the determination of the sheet types of the sheets P of all the selected detection targets (paper feed cassettes / trays) has been completed (step S207: Yes), the process proceeds to step S209.

[0068] In step S209, the CPU 201 determines whether the sheet type determination of the sheets P of all the detection targets (paper feed cassettes / trays) could be detected. If the sheet type determination could be detected for all the detection targets (step S209: Yes), the subsequent processing steps S210 to S212 are the same as the processing steps S107 to S109 described with reference to FIG. 4, and thus the description is omitted.

[0069] On the other hand, when there is a paper feed cassette / tray for which sheet type discrimination is not detected (step S209: No), the operation unit 102 displays a sheet type discrimination result including the non-detection indication, and accepts selection of the sheet type (step S213). The sheet type setting screen (third screen) displayed on the operation unit 102 at this time is shown in FIG. 9. In the sheet type setting screen of FIG. 9, in addition to the sheet type discrimination results of all detected detection targets (paper feed cassettes / trays), a display indicating non-detection is included for the paper feed cassettes / trays that are not detected. Further, in the sheet type setting screen of FIG. 9, a message indicating that there is a paper feed cassette / tray that is not detected, a message prompting re-execution of sheet type discrimination, a re-execution button for instructing re-execution, and a registration button for registering the sheet type are displayed. Here, an example in which only one paper feed cassette is not detected is shown, but the number of non-detected paper feed cassettes is not limited to one and may be plural.

[0070] After the CPU 201 displays the sheet type discrimination result including the non-detection indication on the sheet type setting screen (FIG. 9) on the operation unit 102, it determines whether there is a re-execution instruction (the re-execution button has been pressed) (step S214). If there is a re-execution instruction (step S214: Yes), only the non-detected paper feed cassette / tray is set as the detection target (step S215), and the process returns to step S203 to start paper feeding from the target paper feed cassette / tray. If there is no re-execution instruction (step S214: No), it is determined whether the sheet type has been selected for the detected paper feed cassette / tray and there is a registration instruction (the registration button has been pressed) (step S216). If the sheet type has been selected for the detected paper feed cassette / tray and there is a registration instruction (step S216: Yes), only the sheet type of the selected paper feed cassette / tray is registered (step S212), and this process ends. On the other hand, if the sheet type has not been selected for the detected paper feed cassette or there is no registration instruction (step S216: No), the process returns to step S214 and waits in a state of accepting the user's selection.

[0071] According to the above embodiment, as a result of determining the sheet type of all the paper feed cassettes / trays to be detected, if at least one of them is not detected, the user can instruct to re-execute the sheet type determination only for the undetected paper feed cassette / tray. Therefore, the user's workload can be easily reduced without having to perform the operation of the paper feed cassette / tray sheet type determination process that has been detected from the beginning.

[0072] (Embodiment 3) In Embodiment 1, the case where the user correctly stores the sheet to be printed by the image forming apparatus 100 in the paper feed cassette / tray has been described. However, the user may misplace the sheet to be stored in the paper feed cassette and store another type of sheet instead. In this case, there is a problem that it becomes a workload for the user to re-execute the sheet type determination mode from the beginning after correctly storing the sheet to be printed in the paper feed cassette / tray. In this embodiment, means for solving such a problem is provided.

[0073] In this embodiment, the following cases are assumed.

[0074] After the user accidentally stores the sheet in the paper feed cassette and then executes the sheet type determination process of FIG. 4, the sheet type setting screen of FIG. 6(a) is displayed. Even if the result of the sheet type determination is confirmed, the desired sheet type is not among the candidates. That is, the user may notice that the sheet has been accidentally stored only when the sheet type setting screen is displayed. In this case, it is assumed that the user wants to re-execute the sheet type determination mode after changing the sheet stored in one of the paper feed cassettes / trays to the desired one.

[0075] In this embodiment, in such a case, when the sheet type setting screen in FIG. 6(a) is displayed and the sheet stored in one of the paper feed cassettes / trays is changed, the sheet type determination process can be easily re-executed. Specifically, when there is a possibility that the sheet in the paper feed cassette / tray to be detected has been changed, the user is notified of that paper feed cassette / tray. Further, in this embodiment, an instruction to re-execute the sheet type determination process is accepted only for the paper feed cassette / tray in which the sheet may have been changed. As a result, when the user changes a sheet in one of the paper feed cassettes / trays, the user can easily instruct re-execution without having to perform the operation from the beginning of the sheet type determination process, and the work load of the user can be reduced.

[0076] Hereinafter, the sheet type determination process according to this embodiment, which is different from the first embodiment in that it includes the sheet change paper feed cassette / tray re-execution process, will be described.

[0077] FIG. 10 is a flowchart of the sheet type determination process according to this embodiment. This series of processes is started by the CPU 201 when the operation unit 102 instructs the execution of the sheet type determination mode in a standby state where the image forming apparatus 100 is not performing an image forming operation. Further, this process is executed by the CPU 201 expanding the program stored in the ROM 202 into the RAM 203.

[0078] Steps S301 to S307 in FIG. 10 are equivalent to the processes from steps S101 to S107 described with reference to FIG. 4, and thus the description thereof is omitted.

[0079] After displaying the sheet type discrimination result in step S307, the CPU 201 detects whether the paper feed cassette set as the detection target in step S302 has been opened or closed (step S308). For example, as shown in FIG. 5(b), when two paper feed cassettes 1 and 2 are set as the detection targets, based on the output results of the cassette 1 open / close detection sensor 221 and the cassette 2 open / close detection sensor 222, it is detected whether the selected paper feed cassettes 1 and 2 are open or closed. If there is an opened paper feed cassette, it can be determined that there is a possibility that the user opened or closed the paper feed cassette for sheet replacement, and there is a possibility that the stored sheet P has been replaced. Note that the paper feed cassettes 1 and 2 in FIG. 5 are the names given to the paper feed cassettes 131a and 131b in FIG. 2, respectively. Also, when only the tray is set as the detection target in step S302 and no paper feed cassette is set, it is determined that there is no opening or closing of the set paper feed cassette.

[0080] The CPU 201 detects whether the sheet P has been repositioned (i.e., removed and reinstalled) on the tray set as the detection target in step S302 (step S309). For example, when tray 1 is set as the detection target on the paper feed cassette / tray selection screen in FIG. 5(a), based on the output result of the tray presence / absence detection sensor 225, it is detected whether the sheet P set on the selected tray 1 has been removed and repositioned. If the sheet P has been repositioned, it can be determined that there is a possibility that the sheet P has been replaced. Note that when only the paper feed cassette is set as the detection target in step S302 and no tray is set, it is determined that there is no repositioning of the sheet on the set tray.

[0081] In steps S308 and S309, the CPU 201 determines whether it has detected either the opening and closing of the paper feed cassette set as the detection target or the repositioning of the sheet to the tray set as the detection target (step S310). If it has not detected either (step S310: No), it determines whether a sheet type has been selected and there is a registration instruction (step S311). If the sheet type has not been selected or there is no registration instruction (step S311: No), it returns to step S308. If the sheet type has been selected and there is a registration instruction (step S311: Yes), it registers the selected sheet type for the paper feed cassette / tray that is the detection target (step S312) and ends this process.

[0082] If there has been an opening and closing of the paper feed cassette set as the detection target or a repositioning of the sheet in the tray set as the detection target (step S310: Yes), it proceeds to step S313.

[0083] In step S313, it displays a sheet type setting screen that shows the treatment content executed on the operation unit 102 (the opening and closing of the paper feed cassette or the repositioning of the sheet P to the tray) and accepts the selection of the sheet type on the same screen. For example, after the sheet type setting screen shown in Fig. 5(b) is displayed on the operation unit 102 and then the cassette 2 is opened and closed, the sheet type setting screen (the fourth screen) shown in Fig. 11(a) is displayed. On the sheet type setting screen (Fig. 11(a)), in addition to the sheet type discrimination result of the selected paper feed cassette / tray and the registration button for registering the sheet type, a message indicating that the paper feed cassette has been opened and closed is displayed. Furthermore, on the sheet type setting screen (Fig. 11(a)), a message prompting the re-execution of the sheet type discrimination of the detection target (here, cassette 2) for which the sheet can be changed and a re-execution button for instructing the re-execution are displayed.

[0084] Also, when the user selects the cassette 1 and the tray 1 as detection targets on the sheet type setting screen of Fig. 5(a), and the sheet P on the tray is re-placed, the sheet type setting screen (the fifth screen) shown in Fig. 11(b) is displayed. On the sheet type setting screen (Fig. 11(b)), in addition to the sheet type discrimination result of the selected paper feed cassette / tray and the registration button for registering the sheet type, a message indicating that the sheet on the tray has been re-placed is displayed. Further, on the sheet type setting screen (Fig. 11(b)), a message prompting re-execution of the sheet type discrimination of the detection target (here, the tray 1) for which the sheet can be changed and a re-execution button for instructing the re-execution are displayed.

[0085] Note that, although an example of a paper feed cassette / tray where the sheet can be changed has been shown so far, the paper feed cassette / tray where the sheet can be changed is not limited to one and may be plural.

[0086] Returning to Fig. 10, the CPU 201 determines whether there is a re-execution instruction for the sheet type setting screen displayed on the operation unit 102 in step S313 (whether the re-execution button has been pressed) (step S314). If there is a re-execution instruction (step S314: Yes), it proceeds to step S315, and if there is no re-execution instruction (step S314: No), it proceeds to step S316.

[0087] In step S315, only the detection targets where the sheet can be changed (paper feed cassette 2 in Fig. 11(a), tray 1 in Fig. 11(b)) are set as detection targets again, it returns to step S303, and paper feeding is started from the target paper feed cassette / tray.

[0088] In step S316, it is determined whether a sheet type has been selected for the paper feed cassette / tray that has been selected as the detection target and for which the sheet type discrimination result is being displayed, and whether there is a registration instruction. If a sheet type has been selected and there is a registration instruction (step S316: Yes), the selected sheet type of the paper feed cassette / tray is registered (step S312), and this process ends. If no sheet type has been selected or there is no registration instruction (step S316: No), the process returns to step S314, and the process waits in a state of accepting the user's selection.

[0089] According to the above process, when there is a possibility that the sheet in the paper feed cassette / tray of the detection target has been changed while the sheet type discrimination result is being displayed on the sheet type setting screen, the user is made to accept re-execution of the sheet type discrimination that designates the possible detection target as the detection target again. As a result, the user can easily instruct re-execution only for the paper feed cassette / tray that may be changed without having to operate from the beginning of the sheet type discrimination process, and the work load of the user can be reduced.

[0090] (Other Embodiments) The present invention can also be realized by supplying a program that realizes one or more functions of the above-described embodiment to a system or apparatus via a network or a storage medium, and having one or more processors in a computer of the system or apparatus read and execute the program. Further, it can also be realized by a circuit (for example, an ASIC) that realizes one or more functions.

[0091] The invention is not limited to the above-described embodiment, and various changes and modifications can be made without departing from the spirit and scope of the invention. Therefore, the claims are attached to disclose the scope of the invention.

[0092] As described above, the preferred embodiments of the present invention have been described. However, the present invention is not limited to these embodiments, and various modifications and changes are possible within the scope of the gist thereof.

[0093] The disclosure of this embodiment includes the following configurations, methods, and programs. (Configuration 1) An image forming apparatus comprising: a plurality of sheet storage means for storing sheets; conveyance means for conveying the sheets fed from each of the plurality of sheet storage means along a conveyance path; image forming means for forming an image on the sheets conveyed by the conveyance means; measurement means provided in the conveyance path for measuring physical property values of the sheets conveyed through the conveyance path; and a user interface having an input interface and an output interface, the apparatus further comprising control means for executing sheet type discrimination for discriminating the sheet type of the sheets based on the physical property values measured by the measurement means, wherein the control means displays, on the output interface, a first screen for collectively selecting two or more of the plurality of sheet storage means as objects of the sheet type discrimination, and when two or more of the sheet storage means are selected by the user via the input interface, the control means continuously executes the sheet type discrimination for each of the two or more selected sheet storage means. (Configuration 2) The control means collectively displays, for each of the two or more sheet storage means, sheet type setting candidates that are the results of the sheet type discrimination, and displays, on the output interface, a second screen for collectively setting the sheet types selected by the user from among the sheet type setting candidates, and when the sheet types for each of the two or more sheet storage means are selected by the user via the input interface, the control means collectively sets the sheet types selected by the user for each of the two or more sheet storage means. The image forming apparatus according to Configuration 1, characterized in that. (Configuration 3) When, as a result of continuously executing the sheet type discrimination for each of the two or more sheet storage means, there is a sheet storage means for which the result of the sheet type discrimination is undetected, the control means displays, on the output interface, a third screen for re-executing the sheet type discrimination only for the sheet storage means for which the result of the sheet type discrimination is undetected, and when the re-execution is accepted via the input interface, the control means re-executes the sheet type discrimination only for the sheet storage means for which the result of the sheet type discrimination is undetected. The image forming apparatus according to Configuration 1, characterized in that. (Configuration 4) When there is a sheet storage means among the two or more sheet storage means, where the physical property value of the sheet is equal to or less than the non-determinable discrimination threshold value, the control means determines that the sheet storage means is a sheet storage means for which the result of the sheet type discrimination is not detected, in the image forming apparatus according to Configuration 3. (Configuration 5) The measuring means irradiates ultrasonic waves onto the sheet being conveyed through the conveyance path, measures the physical property value of the sheet based on the attenuation amount of the ultrasonic waves that have passed through the sheet, and the physical property value of the sheet is the attenuation amount, in the image forming apparatus according to Configuration 4. (Configuration 6) The plurality of sheet storage means includes a plurality of paper feed cassettes each provided with opening / closing detection means for detecting opening and closing. In a state where the second screen is being displayed, if there is a paper feed cassette among the plurality of paper feed cassettes for which the opening / closing detection means has detected opening and closing, a fourth screen for accepting re-execution of the sheet type discrimination is displayed on the output interface only for the paper feed cassette for which the opening / closing has been detected. When the re-execution is accepted via the input interface, the sheet type discrimination is re-executed only for the paper feed cassette for which the opening / closing has been detected, in the image forming apparatus according to any one of Configurations 2 to 5. (Configuration 7) In the image forming apparatus according to Configuration 6, a message prompting re-execution of the sheet type discrimination for the paper feed cassette for which the opening / closing has been detected is displayed on the fourth screen. (Configuration 8) The plurality of sheet storage means includes at least one tray provided with sheet presence / absence detection means for detecting the presence or absence of the stored sheet. In a state where the second screen is being displayed, if there is a tray among the at least one tray for which the sheet presence / absence detection means has detected removal and reinstallation of the stored sheet, a fifth screen for accepting re-execution of the sheet type discrimination is displayed on the output interface only for the tray for which the removal and reinstallation of the stored sheet has been detected. When the re-execution is accepted via the input interface, the sheet type discrimination is re-executed only for the tray for which the removal and reinstallation of the stored sheet has been detected, in the image forming apparatus according to any one of Configurations 2 to 7. Configuration 9: The image forming apparatus according to Configuration 8, wherein a message prompting re-execution of sheet type discrimination for the tray that has detected removal and reinstallation of the stored sheet is displayed on the fifth screen. Method 1: A control method for an image forming apparatus including a plurality of sheet storage means for storing sheets, conveyance means for conveying the sheets fed from each of the plurality of sheet storage means along a conveyance path, image forming means for forming an image on the sheets conveyed by the conveyance means, measurement means provided in the conveyance path for measuring physical property values of the sheets conveyed through the conveyance path, and a user interface including an input interface and an output interface, the control method having a control step of executing sheet type discrimination for discriminating the sheet type of the sheet based on the physical property values measured by the measurement means, the control step including displaying, on the output interface, a first screen for collectively selecting two or more of the plurality of sheet storage means as objects of the sheet type discrimination, and when the two or more sheet storage means are selected by the user via the input interface, continuously executing the sheet type discrimination for each of the two or more sheet storage means. Program 1: A program for causing a computer to function as each means of the image forming apparatus according to any one of Configurations 1 to 9. Description of Reference Numerals

[0094] 100 Image forming apparatus 100B Image forming unit 100D Conveyance unit 131a - 134a Paper feed cassettes 135a Manual feed tray 201 CPU 210 Media sensor 221 - 224 Cassette open / close detection sensors 225 Tray presence / absence detection sensor

Claims

1. a plurality of sheet storage means for storing sheets; conveying means for conveying the sheets fed from each of the plurality of sheet storage means along a conveyance path; image forming means for forming an image on the sheets conveyed by the conveying means; measuring means provided in the conveyance path for measuring physical property values of the sheets conveyed through the conveyance path; a user interface having an input interface and an output interface; an image forming apparatus comprising: control means for executing sheet type discrimination for discriminating the sheet type of the sheets based on the physical property values measured by the measuring means, wherein the control means: displays, on the output interface, a first screen for collectively selecting two or more of the plurality of sheet storage means as objects of the sheet type discrimination; When two or more of the sheet storage means are selected by the user via the input interface, the image forming apparatus is characterized in that the sheet type discrimination is continuously executed for each of the two or more sheet storage means.

2. The control means: collectively displays, for each of the two or more sheet storage means, sheet type setting candidates that are the results of the sheet type discrimination, and displays, on the output interface, a second screen for collectively setting the sheet type selected by the user from among the sheet type setting candidates; When the sheet type for each of the two or more sheet storage means is selected by the user via the input interface, the image forming apparatus according to claim 1, characterized in that the sheet type selected by the user is collectively set for each of the two or more sheet storage means.

3. The control means: As a result of continuously executing the sheet type discrimination for each of the two or more sheet storage means, when a sheet storage means whose sheet type discrimination result is undetected occurs, a third screen for re-executing the sheet type discrimination only for the sheet storage means whose sheet type discrimination result is undetected is displayed on the output interface; When the re-execution is accepted via the input interface, the image forming apparatus according to claim 1, characterized in that the sheet type discrimination is re-executed only for the sheet storage means whose sheet type discrimination result is undetected.

4. The control means: In the case where, among the two or more sheet storage means, there is a sheet storage means in which the physical property value of the sheet is equal to or less than the determination impossible discrimination threshold value, the image forming apparatus according to claim 3, characterized in that the sheet storage means is determined as a sheet storage means in which the result of the sheet type discrimination is not detected.

5. The measuring means irradiates the sheet conveyed through the conveyance path with ultrasonic waves, and measures the physical property value of the sheet based on the attenuation amount of the ultrasonic waves transmitted through the sheet. The image forming apparatus according to claim 4, characterized in that the physical property value of the sheet is the attenuation amount.

6. The plurality of sheet storage means includes a plurality of paper feed cassettes each provided with an opening / closing detection means for detecting opening and closing. In a state where the second screen is being displayed, if there is a paper feed cassette among the plurality of paper feed cassettes in which the opening / closing detection means has detected opening and closing, a fourth screen for accepting re-execution of the sheet type discrimination is displayed on the output interface only for the paper feed cassette in which the opening / closing has been detected. The image forming apparatus according to claim 2, characterized in that when the re-execution is accepted via the input interface, the sheet type discrimination is re-executed only for the paper feed cassette in which the opening / closing has been detected.

7. The image forming apparatus according to claim 6, characterized in that a message prompting re-execution of the sheet type discrimination for the paper feed cassette in which the opening / closing has been detected is displayed on the fourth screen.

8. The plurality of sheet storage means includes at least one tray provided with a sheet presence / absence detection means for detecting the presence or absence of the stored sheet. In a state where the second screen is being displayed, if there is a tray among the at least one tray in which the sheet presence / absence detection means has detected removal and reinstallation of the stored sheet, a fifth screen for accepting re-execution of the sheet type discrimination is displayed on the output interface only for the tray. The image forming apparatus according to claim 2, characterized in that when the re-execution is accepted via the input interface, the sheet type discrimination is re-executed only for the tray in which removal and reinstallation of the stored sheet have been detected.

9. The image forming apparatus according to claim 8, characterized in that a message prompting re-execution of the sheet type discrimination for the tray in which removal and reinstallation of the stored sheet have been detected is displayed on the fifth screen.

10. A plurality of sheet storage means for storing sheets Conveying means for conveying the sheets fed from each of the plurality of sheet storage means along a conveyance path; Image forming means for forming an image on the sheet conveyed by the conveying means; Measuring means provided in the conveyance path for measuring physical property values of the sheet conveyed through the conveyance path; A user interface including an input interface and an output interface; A control method for an image forming apparatus comprising: Having a control step of executing sheet type discrimination for discriminating the sheet type of the sheet based on the physical property value measured by the measuring means; The control step includes: Displaying, on the output interface, a first screen for collectively selecting two or more of the plurality of sheet storage means as objects of the sheet type discrimination; When two or more of the sheet storage means are selected by the user via the input interface, continuously executing the sheet type discrimination for each of the two or more sheet storage means.

11. A program for causing a computer to function as each means of the image forming apparatus according to Claim 1.

Images