JP3885609B2 - Image forming apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an image forming apparatus including a paper tray having a paper placing table that moves up and down.
[0002]
[Prior art]
In recent years, an increasing number of image forming apparatuses such as copying machines and printers are provided with a large capacity paper tray capable of storing thousands of sheets. Such a large-capacity paper tray generally includes a paper placing table that can be raised and lowered. When the user sets a sheet bundle on the mounting table and inserts the paper tray into the main body of the image forming apparatus, the paper mounting table rises until the upper surface of the paper reaches a predetermined discharge position, thereby Is ready to feed.
[0003]
Also, recent paper trays generally support a plurality of paper sizes. There are many paper trays equipped with the above-described up-and-down paper placement table that can handle a plurality of paper sizes.
[0004]
[Problems to be solved by the invention]
When paper of a size smaller than the paper size that can be stored in the paper tray is set on the paper mounting table, an empty space is created on the paper mounting table. Conventionally, the user has spare paper, toner cartridges, etc. in the empty space. Examples of placing foreign objects are known.
[0005]
Here, as shown in FIG. 1A, when the height of the foreign material 130 placed on the paper mounting table 110 is higher than the height of the paper bundle 120, the upper surface of the paper bundle 120 is the paper discharge position of the paper tray 100. When the paper mounting table 110 is raised until it reaches the height of 140, the foreign matter 130 is caught by the structure on the paper tray 100 as shown in FIG. In this case, if the drive system continues to drive the paper placement table 110 up until the upper surface of the paper reaches the paper discharge position 140, the drive system is damaged.
[0006]
If the height of the sheet bundle 120 is higher than the height of the foreign material 130, the above-described problem does not occur at that time. However, if the printing is continued and the amount of paper is reduced, the foreign matter 130 becomes relatively higher, so that the above-mentioned problem eventually occurs.
[0007]
[Means for Solving the Problems]
The present invention has been made in view of such problems, and an object of the present invention is to prevent a failure of the paper platform drive system due to foreign matter.
[0008]
  The present inventionIn one aspect of the present invention, a plurality of paper trays having a paper placing table that can be moved up and down on which a bundle of paper is placed, and when the paper tray is set in the image forming apparatus main body, the paper tray is placed on the paper placing table. An elevating mechanism that raises the sheet placing table until the upper surface of the sheet bundle reaches a predetermined sheet discharge height, and provided for each of the sheet trays, and when the sheet tray is set in the image forming apparatus main body. A foreign matter detection mechanism for detecting whether or not a foreign matter is placed on the paper placement table; and when the foreign matter is detected by the foreign matter detection mechanism, the raising / lowering mechanism prohibits the paper placement stand from being driven up. When a foreign object is detected by the elevating control unit and the foreign object detection mechanism, a notification means for notifying the user of the fact and a display device are provided, and the notification means detects the foreign object with the foreign object detection mechanism. Information indicating whether the paper tray is one of the plurality of paper trays is notified, and the notification means detects foreign matter in the schematic view of the image forming apparatus viewed from the side where the paper tray is inserted or removed. There is provided an image forming apparatus characterized in that a foreign matter detection screen for displaying a displayed paper tray and a paper tray in which no foreign matter is detected in different display forms is displayed on the display device.
[0009]
  In the present invention, when the paper tray is set in the image forming apparatus main body (at this time, the paper mounting table is at the lower position), it is determined whether or not there is a foreign object on the paper mounting table, and the foreign object is detected. Prohibits the drive of the paper table to be lifted, so that it is possible to prevent a failure of the lifting mechanism of the paper table due to foreign matter with high certainty.In addition, it is possible to inform the user of a paper tray with foreign objects in an easy-to-understand manner.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention (hereinafter referred to as embodiments) will be described with reference to the drawings.
[0011]
FIG. 2 is a diagram showing an example of the configuration of an image forming apparatus to which the control processing according to the present invention is applied. In this figure, a copying machine is illustrated as a kind of image forming apparatus. As will be apparent from the following description, the application range of the reset control of the present embodiment is not limited to the copying machine shown in FIG. 2, and can be applied to other image forming apparatuses in general.
[0012]
As shown in this figure, the copying machine includes a document reading unit (IISS: Image Input SubSystem) 10 that optically reads an image shown on a paper document and converts it into an electronic image signal. The document feeder (ADF: Auto Document Feeder) 12 includes a tray on which a bundle of documents to be copied is placed, and feeds the documents placed on the tray to the document reader 10 one by one. A printing unit (IOT: Image Output Terminal) 14 is a mechanism that prints an image of a read original on a sheet-like medium such as paper (hereinafter referred to as “paper”). The printing unit 14 includes a plurality of paper trays 16 and can hold a plurality of types of paper. Further, when printing in large quantities, it is possible to provide a large capacity tray 18 capable of feeding a large quantity of paper on the order of several thousand sheets. The printed paper printed by the printing unit 14 is discharged to the paper discharge unit 20. The paper discharge unit 20 has a plurality of discharge trays 22.
[0013]
A machine operation unit (UI: User Interface) 24 is a user interface mechanism that displays information for operating the copying machine and accepts input of operation instructions from the user. FIG. 3 shows a front view of the machine operation unit 24. The machine operation unit 24 includes a touch panel 26 and various operation buttons. The touch panel 26 has a function of displaying information on the screen and detecting a place where the user touches the screen with a finger. The machine operation unit 24 generates a GUI (Graphical User Interface) display on which various operation menus and operation instruction buttons are displayed and displays the GUI on the touch panel 26, and also displays information on a place touched by the user on the GUI display. 26, the user's input content is interpreted, and a processing instruction corresponding to the input content is transmitted to the machine control unit 28. The operation buttons include, for example, a start button 27a, a numeric keypad 27b, a stop button 27c, an interrupt button 27d, a reset button 27e, a basic screen call button 27f, a job status confirmation button 27g, and a machine status confirmation button 27h for instructing the start of copying. and so on. When these operation buttons are pressed, the machine operation unit 24 transmits a signal indicating that to the machine control unit 28.
[0014]
The machine control unit 28 is a control mechanism for realizing the operation as a copying machine by controlling the units 10 to 26 described above. For example, the machine control unit 28 sends a control signal corresponding to a copy operation instruction (for example, the number of copies or whether double-sided printing is specified) input from the machine operation unit 24 to the document feeding unit 12, the document reading unit 10, the printing unit 14, and the paper. By supplying the paper to the discharge unit 20, a copy process corresponding to the operation instruction is realized. Further, the machine control unit 28 receives a signal indicating the state of the unit from each of the units 10 to 26, and when a malfunction such as a paper jam occurs, performs control according to the malfunction. The machine control unit 28 is realized by processing a control program and various parameter values stored in a ROM or a nonvolatile memory by a processor.
[0015]
Although not shown in FIG. 2, the copier can be connected to a communication network such as a LAN (Local Area Network), receives a print instruction from the host computer via this network, and prints it out. You can also
[0016]
In the apparatus of this embodiment, a foreign matter detection mechanism is provided for the large capacity tray 18. As shown in FIGS. 1A and 1B, the large-capacity tray 18 is a type of paper tray provided with a paper placing table that moves up and down. The foreign matter detection mechanism provided on the large capacity tray 18 will be described.
[0017]
FIG. 4A is a top view of the paper placement table 30 provided in the large capacity tray 18. The sheet mounting table 30 is surrounded by an inner wall (not shown) of the large capacity tray 18. For example, the four corners of the upper surface of the sheet mounting table 30 are suspended by wires. By pulling the wire up or down, the paper placing table 30 moves up and down while maintaining a horizontal state. The paper to be placed is positioned with its two sides aligned with the two reference sides 31 a and 31 b of the paper placement table 30. The remaining two sides of the sheet are pressed by sheet guides 32a and 32b that slide along the guide rails 34a and 34b. The large-capacity tray 18 is provided with sensors for detecting the positions of the paper guides 32a and 32b, and the size of the loaded paper can be obtained by a combination of the positions of these guides. In the present embodiment, through holes for passing sensors for detecting whether or not paper or other objects are placed at three positions on the upper surface (the surface on which paper is placed) of the paper placement table 30. 36, 38a, 38b are provided.
[0018]
The through hole 36 is provided in the vicinity of the corner where the reference sides 31a and 31b intersect, and any size paper can be set as long as it can be set in the tray 18 regardless of the size of the paper. The position is determined to cover.
[0019]
On the other hand, the through holes 38a and 38b are provided on the side away from the position where the paper is set, that is, on the side close to the side opposite to the reference side 31a. This place is a place where a large empty space is created when a small paper is set on the tray 18, and the user tends to place a spare paper or a toner cartridge.
[0020]
FIG. 4B is a diagram schematically showing a cross section of the large capacity tray 18 along the line a-a ′ shown in FIG. This figure shows a state when the paper mounting table 30 is at the lowest position in the elevation range. The paper mounting table 30 is accommodated in the tray casing 19. The sensor 40 is installed on the floor surface 19a of the tray housing 19 just below the through hole 38a.
[0021]
As shown in FIG. 5A, the sensor 40 includes a contact 42 that comes into contact with an object placed on the paper placement table 30 and a photo interrupter 46. The contact 42 is rotatable up and down as indicated by arrows A and A ′ around a shaft 44 supported by a support structure (not shown). An overhang part 42 b is provided below the contact 42. A view of the photo interrupter 46 viewed from the direction of arrow B is shown in FIG. As shown in this figure, the photo interrupter 46 has a transmissive structure in which light emitted from a light emitting diode (LED) 47a is detected by a photodetector (PD) 47b provided on the opposite side.
[0022]
The contact 42 is biased in the direction of arrow A (counterclockwise in the figure) by a spring mechanism or the like. Therefore, when the sheet mounting table 30 is lowered to the lowest position and no sheet or other object is placed at the position of the through hole 38a, as shown in FIG. It protrudes from the through hole 38 a to the upper surface side of the sheet mounting table 30. In this case, the protruding portion 42b of the contact 42 does not block between the LED 47a and the PD 47b of the photo interrupter 46.
[0023]
On the other hand, as shown in FIG. 5B, when the sheet 120 or other object is placed on the through hole 38a, the tip 42a of the contact 42 is pressed by the weight of the sheet or object, and the contact 42 Rotates in the direction of arrow A ′ (clockwise in the figure), and as a result, the overhanging portion 42b blocks between the LED 47a and the PD 47b.
[0024]
With such a mechanism, the sensor 40 can detect whether an object is placed at a position corresponding to the sensor 40 of the paper placement table 30 when the paper placement table 30 is at the lowest position.
[0025]
Although the through hole 38a has been described above, a similar sensor 40 is provided for the through holes 36 and 38b, and it is configured to detect whether or not an object is placed at that position.
[0026]
Each of these sensors 40 is the same in terms of a major role of detecting whether or not an object is placed thereon, but the detailed role differs depending on the arrangement position. That is, the sensor 40 installed at the position of the through hole 36 can be used to determine whether or not the paper is set, and the sensor 40 installed in the through holes 38a and 38b is for detecting foreign matters other than the paper. Can be used.
[0027]
Since these sensors 40 are provided on the casing floor 19a of the large capacity tray 18, effective detection can be performed only when the paper mounting table 30 is lowered to the lowest position. When the paper is replenished / replaced, the paper mounting table 30 is lowered to the lowest position. Therefore, when the large-capacity tray 18 on which new paper is set is set in the image forming apparatus main body, the sensor 40 detects the presence or absence of an object. be able to.
[0028]
In the image forming apparatus according to the present embodiment, whether or not there is a foreign object on the large-capacity tray 18 is determined based on the detection signals of these three sensors 40 and information on the paper size obtained from the positions of the paper guides 32a and 32b. judge. The basic concept of foreign matter determination is that “if an object is detected by the sensor 40 in a place where there should not be paper, it is determined that there is a foreign matter”. It can be determined from the paper size whether the location of a certain sensor 40 should be a paper.
[0029]
For example, in the example shown in FIG. 6A, a foreign object 160 is placed on the paper placement table 30 in addition to the paper bundle 150 set at a regular position. In this case, it is detected by the sensor 40 of the through hole 36 that the sheet bundle 150 is set, and the sheet size of the sheet bundle 150 can be known by the combination of the positions of the sheet guides 32a and 32b. Since the through holes 38a and 38b are both out of the range in which the sheet bundle 150 exists, it can be determined that a foreign object is present when the sensor 40 corresponding to at least one of them detects an object. In the example of FIG. 6A, since the foreign object 160 is placed over both the through holes 38a and 38b, both the sensors 40 detect the foreign object 150.
[0030]
On the other hand, in the example shown in FIG. 6B, since the sheet bundle 150 is of a horizontally long type, when the sheet bundle 150 is correctly set, not only the sensor 40 corresponding to the through hole 36 but also the through hole 38a is supported. The sensor 40 which detects also detects an object. In this case, it is determined that there is a foreign object only when the sensor 40 corresponding to the through hole 38b detects an object.
[0031]
Further, as shown in FIG. 6C, in the case where the foreign material 160 is placed even though the sheet bundle is not set, the sensor 40 at the position of the through hole 36 does not detect the object, but the through hole At least one of 38a and 38b will detect an object. Thereby, it can be seen that there is a foreign object.
[0032]
As described above, if it is known whether or not each sensor 40 provided for each position of the paper placing table 30 detects an object and information on the set paper size, whether or not a foreign object is placed by the combination. Can be determined.
[0033]
This determination is performed by the machine control unit 28. The machine control unit 28 receives the detection results of the sensors 40 and the position information of the paper guides 32a and 32b, and determines the presence or absence of foreign matter from them. For this determination, for example, for each paper size, a table indicating whether each combination of detection results (with / without objects) of each sensor 40 is “with foreign matter” or “without foreign matter”. Create and register. The paper size can be determined from the combination of the positions of the paper guides 32a and 32b.
[0034]
When the machine control unit 28 detects that there is a foreign object on the large-capacity tray 18 in this way, the machine control unit 28 displays a warning screen informing the presence of the foreign object on the touch panel 26 and prompts the user to remove the foreign object.
[0035]
In the above description, the foreign matter detection mechanism is provided on the large-capacity tray 18, but the same foreign matter detection mechanism can be provided on the other paper trays 16.
[0036]
Next, an example of a processing procedure at the time of paper replenishment and replacement in the image forming apparatus of this embodiment will be described.
[0037]
When the paper in the paper tray runs out during the printing process, as shown in FIG. 7, the machine control unit 28 interrupts the printing process (S10), lowers the paper tray 30 of the tray (S12), and the paper A screen showing a message for instructing replenishment is displayed on the touch panel 26 (S14). The user sees this display and pulls out the paper tray for paper replenishment.
[0038]
Even when the message indicating that the paper has run out is not displayed as described above, the user can pull out the paper tray and refill the paper or set a paper of a different size as necessary.
[0039]
When the user pulls out the paper tray, the machine control unit 28 detects this (S20), displays a screen indicating that the paper tray has been removed on the touch panel 26, and waits for the tray to be inserted again. (S22). When detecting that the paper tray is inserted, the machine control unit 28 executes the above-described foreign matter determination processing based on the positional information of the paper guides 32a and 32b of the tray and the detection information of each sensor 40 (S24). It is determined whether there is a foreign object on the tray (S26). If it is determined in step S26 that there is a foreign object, the use of the tray is prohibited, and the sheet placement table 30 in the tray is not allowed to rise (S28). At this time, the machine control unit 28 stores in the nonvolatile memory, for example, that the tray 18 has been disabled.
[0040]
In some cases, a plurality of paper trays may be pulled out at the same time. In this case, the foreign matter determination process may be executed when all the trays are inserted. In this case, the foreign matter determination process (S24) is performed for all the paper trays that have been pulled out at the same time.
[0041]
If it is determined in step S26 that there is no foreign matter, the machine control unit 28 determines whether there is a paper tray that is disabled at that time (S30).
[0042]
If there is a use-prohibited paper tray, the machine control unit 28 cancels the use-prohibited state of each of the use-prohibited paper trays and permits the rise of the paper placement table of those trays (S32). Then, it is determined whether there is an interrupted job (S34).
[0043]
If the paper runs out in the middle of the printing process, the job is interrupted, and the result of this determination is affirmative (Y). In this case, the machine control unit 28 displays a job continuation confirmation screen as illustrated in FIG. 9 on the touch panel 26 and asks the user whether to continue or cancel the suspended job (S36). The user may touch the “restart printing” button 204 to continue the job, and touch the “delete job” button 202 to cancel the job. The machine control unit 28 acquires information indicating the user's instruction for this screen from the machine operation unit 24, and determines whether the instruction from the user is a job continuation based on the information (S38). If the user instruction is to continue the job, the machine control unit 28 resumes the interrupted job printing process (S40) and returns to the normal processing routine. If the user instruction is to cancel the job, the machine control unit 28 deletes the interrupted job (S42) and returns to the normal processing routine.
[0044]
If the user does not execute the printing process and the user refills the paper tray or replaces the paper, the job is not interrupted, so the determination result in step S34 is negative. (N). In this case, processing for continuing the job is unnecessary, and it is only necessary to immediately return to the normal processing routine.
[0045]
The image forming apparatus according to the present embodiment is a type in which the document reading process by the document reading unit 10 and the printing process on a sheet by the printing unit 14 can be performed independently. Therefore, even if there is a foreign matter in the paper tray and the use is prohibited, and the printing unit 14 cannot print, the original can be read. The paper tray only needs to be usable when printing is performed by the printing unit 14. Therefore, in the present embodiment, when a foreign object on the paper tray is detected, the use of the paper tray is disabled (S28), and no warning is issued to the user. Are printed in the order in which they are printed by the printing unit 14, a flow of issuing a foreign object warning to the user. The flow of such processing will be described with reference to FIG.
[0046]
When the user sets a document on the document feeding unit 12 and presses the start button 27 a, the document is optically read by the document reading unit 10, and the image data of the document is stored in the memory under the control of the machine control unit 28. (S50). Then, the machine control unit 28 registers the image data of the document set on the document feeding unit 12 as one job (S52), and the printing unit 14 finishes printing the job group registered before the job. Wait for. When printing of these job groups is completed, the printing order of the jobs registered in step S52 comes. Of course, if there is no preceding unprinted job at the time of document reading, the printing order will come soon after the document reading starts.
[0047]
When the printing order arrives, the machine control unit 28 determines whether or not the paper tray selected as the paper supply source of the job is in a use-prohibited state (S54). Here, the paper tray of the paper supply source for the job can be explicitly specified by the user from the machine operation unit 24, or can be automatically selected by the machine control unit 28. The latter is based on, for example, a copy function such as a document size or 2-in-1 (a function for printing a two-page document image on one page of paper) specified by the user, and the machine control unit 28 has a sheet having an optimal sheet size. The tray is selected and is also called APS (Auto Paper Select).
[0048]
If it is determined in step S54 that the selected paper tray is not in a use-prohibited state, the machine control unit 28 causes the printing unit 14 to start print processing for the job (S56).
[0049]
If it is determined in step S54 that the selected paper tray is in a use-prohibited state, the machine control unit 28 stops the printing process of the printing unit 14 and suspends the job (S58). A foreign object warning screen indicating that there is a foreign object is displayed on the touch panel 26 (S60).
[0050]
FIG. 11 shows an example of the display of the foreign object warning screen. In this example, the message area 210 of the foreign matter warning screen displays a message indicating the presence of foreign matter in the paper tray and that the foreign matter should be removed. In the main display area 220, a tray number 222 of a paper tray in which foreign matter exists is displayed together with a similar foreign matter warning message 224. Further, on this screen, for the sake of easy understanding by the user, a schematic diagram 226 showing a state in which the image forming apparatus is viewed from the front (that is, the surface on the side where the paper tray is pulled out) is displayed. It is displayed in a different display form from the tray 230 that is not so. Particularly in this example, it is necessary to draw out the tray 228 to eliminate the abnormality by showing the tray having no foreign matter 230 in the state where it is inserted into the image forming apparatus and showing the tray 228 having foreign matter in the drawn state. This is easy for the user to understand. Here, for example, by displaying an animation of a state in which the tray 228 with foreign objects is gradually pulled out, it is possible to easily show the user the operation content to be performed (pull out the tray and take action). .
[0051]
The user recognizes from the display that there is a foreign object on the paper tray, and determines how to proceed. When removing the foreign matter, the user pulls out the paper tray with the foreign matter shown in the display from the main body of the image forming apparatus, removes the foreign matter, and returns it to the main body. The processing procedure of the image forming apparatus at this time has already been described with reference to FIG.
[0052]
In addition, on the foreign object warning screen illustrated in FIG. 11, an “other job priority” button 232, a “job cancel” button 234, and a “close” button 236 are displayed as GUI (graphical user interface) buttons. The user can press these buttons 232 to 236 instead of removing the foreign matter from the paper tray or before removing the foreign matter.
[0053]
The “job cancel” button 234 is a button for instructing to cancel (cancel) the job interrupted in step S58. The machine control unit 28 monitors whether or not the “job cancel” button 234 is pressed (S62). If this button 234 is pressed, the job is deleted from the job queue (S66), and a foreign object warning is issued. The screen is closed (S70) and the process returns to the normal processing procedure. Therefore, if there is a job waiting for printing, the processing from step S54 is repeated. After the user presses the “job cancel” button 234, the user can take out the foreign matter. Even if the foreign matter is not removed from the paper tray after the “Job Cancel” button 234 is pressed, if a subsequent job uses another paper tray, printing is continued as it is, and the paper tray with foreign matter is used. When the job printing order arrives, the foreign object warning screen is displayed again.
[0054]
The “other job priority” button 232 is a button for instructing to process other jobs waiting for printing first instead of the job interrupted in step S58. The machine control unit 28 monitors whether or not the “other job priority” button 232 is pressed (S64). If this button 232 is pressed, the processing order of the interrupted job in the job queue is displayed. In accordance with a predetermined rule (S68), the foreign object warning screen is closed (S70), and the process returns to the normal processing procedure. In this case, the print order of the job next to the interrupted job comes, and the processing from step S54 is repeated. The user can perform an operation to remove foreign matter from the paper tray while another job is being executed. There are various rules for lowering the job processing order depending on the actual situation of the operation site, for example, lowering the order by one or lowering the order to the end of the queue. By providing a function for preferentially executing another job when the job is interrupted in this way, it is possible to start processing of the subsequent job without waiting for the foreign substance removal work. Whether there are other jobs waiting to be printed can be determined by, for example, pressing the job status confirmation button 27h of the machine operation unit 24 and displaying the job list on the touch panel 26.
[0055]
When the “Close” button 236 is pressed, the foreign object warning screen is closed, but the job interruption state is not resolved.
[0056]
In the image forming apparatus according to the present embodiment, it is possible to determine the presence or absence of foreign matter on the paper tray by the procedure described above, and notify the user of the presence of foreign matter and prompt removal thereof. The paper tray in which the foreign matter is detected is prohibited from being used, and the use prohibited state is not released until the foreign matter is removed, and the upward movement of the paper placement table 30 is not permitted. An adverse effect on the mechanism can be prevented or reduced.
[0057]
The image forming apparatus according to the present embodiment can also display a machine information screen as illustrated in FIG. 12 on the touch panel 26 by pressing the machine state confirmation button 27h of the machine operation unit 24. In the main display area of the machine information screen, a schematic diagram 250 showing a state where the image forming apparatus is viewed from the front, and a tray state list 240 showing the state of each paper tray are displayed. In the tray status list 240, an icon display 242 indicating the presence of a foreign object is displayed in the paper tray column where the foreign object exists, and an icon display 244 indicating a normal state is displayed for a normal paper tray. For example, if a user presses the “Close” button 244 on the foreign object warning screen (see FIG. 11) and leaves without performing foreign object removal, and the job is suspended, By calling up the information screen, it is possible to know that there is a foreign object in a certain paper tray and to know the cause of the job interruption.
[0058]
The above example is a case of a paper tray of a type that can automatically detect the paper size from the positions of the paper guides 32a and 32b. In the case of a paper tray that does not have a mechanism for automatically detecting the paper size, the user generally registers the paper size to be set in the tray in advance in the image forming apparatus. The foreign matter presence / absence determination may be performed based on the information.
[0059]
In addition to the method described above, a method for providing a sensor for detecting a foreign object at a position different from the sensor for detecting the upper surface of the paper is considered in addition to the method described above. It is done. In this method, when the paper placement table 30 is raised, when it is detected that an object contacts the foreign matter detection sensor, the rise of the paper placement table 30 is stopped and a warning message is displayed. Also by this method, it is possible to prevent the paper mounting table drive mechanism from being damaged by foreign matter.
[0060]
However, the above-described method described with reference to FIGS. 4 to 12 determines the presence or absence of foreign matter immediately after the paper tray is set on the main body (that is, before the paper placing table 30 is lifted) rather than this method. Therefore, it is possible to detect the presence or absence of foreign matter at an early stage, and to reduce waste of time.
[0061]
In the procedure shown in FIGS. 8 and 10, the user is not notified when a foreign object is detected in the paper tray, but is notified when printing using the paper tray starts. Instead of this, as a matter of course, a procedure for notifying of foreign object detection using a foreign object warning screen or the like at the time when the foreign object is detected may be used.
[0062]
Further, in the example shown in FIG. 4 and the like, the sensors 40 for detecting the object placed on the paper mounting table 30 are arranged at three locations. However, the number of sensors 40 arranged and the locations thereof are the configurations illustrated in FIG. It is not limited to. If more sensors 40 are arranged, more accurate foreign object determination can be performed.
[0063]
Further, a sensor other than the mechanical sensor 40 illustrated in FIG. 5 can be used as a sensor for detecting an object on the paper placing table 30. For example, a similar foreign matter determination is possible even in a configuration in which a pressure sensor is provided in place of the through hole at the position of the through hole 36, 38a, 38b on the paper placement table 30 to thereby determine whether or not there is an object contact It can be performed.
[Brief description of the drawings]
FIG. 1 is a diagram for explaining a problem when a foreign object is placed in a paper tray.
FIG. 2 is a diagram schematically illustrating a schematic configuration of an image forming apparatus.
FIG. 3 is a diagram illustrating an appearance of an operation panel of a machine operation unit.
FIG. 4 is a diagram for explaining a paper placement table and a foreign object detection mechanism provided in the vicinity thereof.
FIG. 5 is a diagram illustrating an example of a configuration of a sensor for detecting foreign matter.
FIG. 6 is a diagram for explaining how to determine the presence or absence of a foreign object.
FIG. 7 is a flowchart illustrating a processing procedure when a sheet runs out during a job.
FIG. 8 is a flowchart illustrating a processing procedure when a paper tray is inserted and removed from the image forming apparatus.
FIG. 9 is a diagram illustrating an example of a job continuation confirmation screen.
FIG. 10 is a flowchart illustrating a copy job processing procedure;
FIG. 11 is a diagram illustrating an example of a foreign object warning screen.
FIG. 12 is a diagram illustrating an example of a machine information screen.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Document reading part, 12 Document feeding part, 14 Printing part, 16 Paper tray, 18 Large capacity tray, 20 Paper discharge part, 22 Discharge tray, 24 Machine operation part, 26 Touch panel, 28 Machine control part, 30 Paper mounting table, 32a, 32b Paper guide, 34a, 34b Guide rail, 36, 38a, 38b Through hole, 40 sensor.

Claims (6)

A plurality of paper trays having a paper placing table capable of moving up and down on which a bundle of paper is placed;
  When the paper tray is set in the image forming apparatus main body, an elevating mechanism that raises the paper placing table until the upper surface of the sheet bundle placed on the paper placing table reaches a predetermined paper discharge height;
  A foreign matter detection mechanism that is provided for each of the paper trays and detects whether or not a foreign matter is placed on the paper placement table when the paper tray is set in the image forming apparatus main body;
  An elevating control unit for prohibiting the elevating drive of the sheet placing table by the elevating mechanism when a foreign object is detected by the foreign object detecting mechanism;
  A notification means for notifying the user when a foreign object is detected by the foreign object detection mechanism;
  A display device;
  With
  The notifying means notifies information indicating which one of the plurality of paper trays is a paper tray in which the foreign matter is detected by the foreign matter detection mechanism;
  In the schematic view of the image forming apparatus viewed from the side where the paper tray is inserted and removed, the notification means displays the paper tray in which the foreign material is detected and the paper tray in which the foreign material is not detected in different display forms. Displaying a detection screen on the display device;
  An image forming apparatus. A paper tray having a paper placing table that can be raised and lowered on which a bundle of paper is placed;
  When the paper tray is set in the image forming apparatus main body, an elevating mechanism that raises the paper placing table until the upper surface of the sheet bundle placed on the paper placing table reaches a predetermined paper discharge height;
  A foreign matter detection mechanism for detecting whether or not foreign matter is placed on the paper placement table when the paper tray is set in the image forming apparatus main body;
  An elevating control unit for prohibiting the elevating drive of the sheet placing table by the elevating mechanism when a foreign object is detected by the foreign object detecting mechanism;
  A notification means for notifying the user when a foreign object is detected by the foreign object detection mechanism;
  With
  The notification means also notifies information indicating an operation content for removing the foreign matter from the paper tray in which the foreign matter is detected;
An image forming apparatus. A paper tray having a paper placing table that can be raised and lowered on which a bundle of paper is placed;
  When the paper tray is set in the image forming apparatus main body, an elevating mechanism that raises the paper placing table until the upper surface of the sheet bundle placed on the paper placing table reaches a predetermined paper discharge height; An image forming apparatus comprising:
  A foreign matter detection mechanism for detecting whether or not foreign matter is placed on the paper placement table when the paper tray is set in the image forming apparatus main body;
  An elevating control unit for prohibiting the elevating drive of the sheet placing table by the elevating mechanism when a foreign object is detected by the foreign object detecting mechanism;
  A machine control unit that prohibits execution of a print job for supplying paper from the paper tray when the foreign material detection mechanism detects that a foreign material is placed on the paper tray;
  An image forming apparatus comprising: The image forming apparatus according to claim 3, wherein
  The machine control unit permits execution of a print job for supplying paper from a paper feed mechanism other than the paper tray even when the foreign material detection mechanism detects that a foreign material is placed on the paper tray.
  An image forming apparatus. A paper tray having a paper placing table that can be raised and lowered on which a bundle of paper is placed;
  When the paper tray is set in the image forming apparatus main body, the paper tray is placed on the paper placement table. An elevating mechanism that raises the sheet placing table until the upper surface of the sheet bundle reaches a predetermined sheet discharge height, and an image forming apparatus comprising:
  A foreign matter detection mechanism for detecting whether or not foreign matter is placed on the paper placement table when the paper tray is set in the image forming apparatus main body;
  An elevating control unit for prohibiting the elevating drive of the sheet placing table by the elevating mechanism when a foreign object is detected by the foreign object detecting mechanism;
  With
  The foreign object detection mechanism is
  Paper size acquisition means for acquiring information on the paper size of the paper placed on the paper tray;
  Sensors installed corresponding to a plurality of predetermined positions on a surface on which the paper of the paper placement table is placed, and detecting whether an object is placed on the sensor; ,
  When it is determined from the relationship between the detection signals of these sensors and the paper size acquired by the paper size acquisition means that an object is placed at a position other than where the paper should be placed, the paper A determination means for determining that there is a foreign object on the mounting table;
  An image forming apparatus comprising:   The image forming apparatus according to claim 5, wherein
  Through holes are respectively provided in the predetermined plurality of positions of the paper mounting table,
  The contact sensor is attached to a bottom surface of a portion of the main body of the image forming apparatus that accommodates the paper tray, protrudes to the paper placement surface side of the paper placement table through the through hole, and makes contact with an object thereon. An image forming apparatus characterized by detecting.

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