JP2005208339A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus with which the time for exchanging a toner container can be checked beforehand and a printing process can be performed with an appropriate quantity of a toner according to a toner residual quantity. <P>SOLUTION: A controller 41 is equipped with a toner residual quantity detection section 411 which detects the toner residual quantity in a toner container 8 in three stages of a multiple level, a middle level and a small (near end) level by the output signals from toner residual quantity detection sensors 81 and 82, a display controller 416 which displays a guide screen including a message to urge economy mode printing to a control panel section 51 when the toner residual quantity attains the middle level, and a mode setting section 415 which changes the printing setting from ordinary mode printing to the economy mode printing when a user selects the economy mode printing by using the operation panel section 51. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an image forming apparatus using electrophotography such as a copying machine, a facsimile machine, and a multifunction machine.

When the amount of toner contained in the toner container in the conventional image forming apparatus is almost zero, that is, when the so-called “near end” is reached, a message prompting the user to replace the toner container is displayed on the display unit. However, when the toner container is not replaced, it is known that the printing mode is automatically switched to the eco mode printing in which the consumed toner amount is reduced from the normal printing mode and the printing is continued (for example, Patent Document 1).
Japanese Patent Laid-Open No. 10-319789

  A user who uses the above-described conventional apparatus may want to confirm the replacement timing of the toner container before the remaining amount of toner becomes near-end from the viewpoint of saving toner consumption. However, since the conventional apparatus displays a message prompting replacement of the toner container after the remaining amount of toner becomes near-end, the user cannot know when to replace the toner container before the remaining amount of toner becomes near-end. . Also, in the conventional image forming apparatus, when printing of a large number of copies is specified immediately before the remaining amount of toner reaches the near end, it reaches the near end in the middle of printing and automatically shifts to eco-mode printing. There is a problem in that image density differs and image quality varies.

  The present invention has been made in view of the above situation, and allows a user to confirm in advance the replacement timing of a toner container and perform printing processing with an appropriate amount of toner according to the remaining amount of toner. An object of the present invention is to provide an image forming apparatus that enables the above.

  An image forming apparatus according to claim 1 includes a main body for forming an image corresponding to image data on a sheet, a replaceable toner container enclosing toner used for image formation, and a remaining amount of toner contained in the toner container. The first toner remaining amount detecting means for detecting whether or not the first toner remaining amount exceeds the first threshold, and when the first toner remaining amount detecting means determines that the toner remaining amount exceeds the first threshold, When the default print setting is set for normal mode printing in which printing is performed with a normal set amount of toner, and the remaining amount of toner is determined to be less than or equal to the first threshold, the amount of toner used is reduced compared to normal mode printing. A second image forming apparatus comprising: a mode changing unit configured to set print settings as default in eco-mode printing; and detecting whether or not the remaining amount of toner exceeds a second threshold value greater than a first threshold value. When the remaining toner amount exceeds the first threshold value and is equal to or less than the second threshold value by the remaining toner amount detecting unit and the first and second remaining toner amount detecting units, the print setting is changed from the normal mode printing to the eco mode. Display means for displaying a first message that prompts the user to change to printing, and when the user selects a change to eco-mode printing in response to the first message, the mode changing means uses a default setting The print setting is changed from the normal mode printing performed to the eco mode printing. According to this configuration, when the toner remaining amount exceeds the first threshold and is equal to or less than the second threshold based on the detection results of the first and second toner remaining amount detecting units, the print setting is performed by the display unit in the normal mode. A message prompting the user to change from printing to eco-mode printing is displayed, and if the change to eco-mode printing is selected in response to the message, eco-mode printing is performed, so that toner consumption is saved. . In addition, since it is possible to notify the user in advance of the time when the toner should be replenished by replacing the toner container or the like, it is possible to raise awareness regarding toner saving.

  An image forming apparatus according to a second aspect includes a main body that forms an image corresponding to image data on a sheet, a replaceable toner container enclosing toner used for image formation, and a remaining amount of toner contained in the toner container. A first toner remaining amount detecting means for detecting whether or not the toner exceeds the first threshold, and the first toner remaining amount detecting means determines that the toner remaining amount exceeds the first threshold Sets the default print setting for normal mode printing, which prints with a normal set amount of toner, and determines that the amount of toner used is less than the normal mode printing if the remaining amount of toner is determined to be less than or equal to the first threshold value. An image forming apparatus comprising mode change means for setting print settings as default in eco-mode printing to be reduced, and detecting whether or not the remaining amount of toner exceeds a second threshold greater than a first threshold If the remaining amount of toner exceeds the first threshold and is equal to or less than the second threshold by the second toner remaining amount detecting means and the first and second toner remaining amount detecting means, the remaining amount of toner during printing Determining whether the toner reaches the first threshold before starting printing, and when the determination determines that the remaining amount of toner reaches the first threshold during printing, the print setting is set to the normal mode. Display means for displaying a second message prompting to change from printing to eco-mode printing, and when the user selects a change to eco-mode printing in response to the second message, the mode changing means Is characterized in that the print setting is changed from normal mode printing set as default to eco mode printing. According to this configuration, the remaining amount of toner exceeds the first threshold value and is equal to or less than the second threshold value based on the detection results of the first and second toner remaining amount detecting units, and the toner is being printed by the determination unit during printing. When it is determined that the remaining amount reaches the first threshold, the display unit displays a message prompting the user to change the print setting from normal mode printing to eco mode printing. When the change is selected, eco-mode printing is performed, so that toner consumption is saved. As a result, it is possible to prevent the processing from being interrupted due to the remaining toner remaining during printing. Further, by performing eco-mode printing from the start of printing, it is possible to prevent the image density from becoming nonuniform at the start and end of printing and to unify the image quality of the printed matter.

  An image forming apparatus according to a third aspect includes a main body that forms an image corresponding to image data on a sheet, a replaceable toner container enclosing toner used for image formation, and a remaining amount of toner contained in the toner container. The first toner remaining amount detecting means for detecting whether or not the first toner remaining amount exceeds the first threshold, and when the first toner remaining amount detecting means determines that the toner remaining amount exceeds the first threshold, When the default print setting is set for normal mode printing in which printing is performed with a normal set amount of toner, and the remaining amount of toner is determined to be less than or equal to the first threshold, the amount of toner used is reduced compared to normal mode printing. A second image forming apparatus comprising: a mode changing unit configured to set print settings as default in eco-mode printing; and detecting whether or not the remaining amount of toner exceeds a second threshold value greater than a first threshold value. When the remaining toner amount exceeds the first threshold value and is equal to or less than the second threshold value by the remaining toner amount detecting unit and the first and second remaining toner amount detecting units, the remaining toner amount is first during printing. A determination unit that determines whether or not the threshold value is reached before the start of printing, and the mode change unit determines that the default value is set when the determination unit determines that the remaining amount of toner reaches the first threshold value during printing. The print setting is changed from the normal mode printing performed to the eco mode printing. According to this configuration, the remaining amount of toner exceeds the first threshold value and is equal to or less than the second threshold value based on the detection results of the first and second toner remaining amount detecting units, and the toner is being printed by the determination unit during printing. When it is determined that the remaining amount reaches the first threshold value, the print setting is automatically changed to eco-mode printing, and eco-mode printing is performed, so that toner consumption is saved. Thereby, the operation of changing the print setting by the user can be omitted, and it is possible to surely prevent the processing from being interrupted due to the remaining amount of toner remaining during printing. Further, by performing eco-mode printing from the start of printing, it is possible to prevent the image density from becoming nonuniform at the start and end of printing and to unify the image quality of the printed matter.

  According to a fourth aspect of the present invention, in the image forming apparatus according to the second or third aspect, the determination unit includes a setting unit that allows a user to set the number of copies to be printed, and a document counting unit that counts the number of documents. Calculating a product of the number of documents counted by the document counting unit and the number of prints set by the setting unit, thereby calculating a planned number of prints to be printed; And an upper limit number storage unit that stores an upper limit number of sheets that can be printed from the first threshold value to the first threshold value, and a print count that counts the number of prints that have been subjected to the printing process And the number of printed sheets is subtracted from the upper limit number of sheets for each printing process until the remaining amount of toner reaches the first threshold value and then the upper limit number of sheets is updated. The limit number update means, the upper limit number stored in the upper limit number storage means until the remaining amount of toner reaches the first threshold value, and the scheduled print number calculated by the calculation means Comparing means for determining whether or not the scheduled number of prints exceeds the upper limit number of sheets, and the determination unit determines that the scheduled number of prints exceeds the upper limit number of sheets by the comparison unit And determining that the remaining amount of toner reaches a first threshold during printing. According to this configuration, the number of prints is subtracted from the upper limit number for each printing process by the upper limit number update unit until the remaining amount of toner reaches the first threshold value until the first threshold value is reached. Since the number of sheets is updated, it is possible to obtain the number of sheets that can be printed before the remaining amount of toner reaches the first threshold as the remaining amount of toner decreases. Are determined, and it is determined that the remaining amount of toner reaches the first threshold during printing when it is determined that the scheduled number of prints exceeds the upper limit number.

  According to a fifth aspect of the present invention, in the image forming apparatus according to the second or third aspect, the determination unit includes a setting unit that allows a user to set the number of copies to be printed, and a document counting unit that counts the number of documents. Calculating a product of the number of documents counted by the document counting unit and the number of prints set by the setting unit, thereby calculating a planned number of prints to be printed; An upper limit number storage means for storing an upper limit number of sheets that can be printed as an initial value after reaching the first threshold value, and a first threshold value after the remaining amount of toner reaches the second threshold value. And the upper limit sheet number updating means for subtracting the scheduled print sheet number from the upper limit sheet number for each printing process to update the upper limit sheet number, and the first threshold value after the toner remaining amount reaches the second threshold value. Until the upper limit sheet number before updating by the upper limit sheet number update unit for the current printing process is compared with the planned print sheet number calculated by the calculation unit, and whether or not the planned print sheet number exceeds the upper limit sheet number Comparing means for determining whether the remaining amount of toner reaches a first threshold during printing when the comparing means determines that the scheduled number of prints exceeds the upper limit number. It is characterized by. According to this configuration, from the time when the remaining amount of toner reaches the second threshold value to the first threshold value, the upper limit number update unit subtracts the scheduled print number from the upper limit number for each printing process, Since the upper limit number of sheets is updated, it is possible to obtain the number of printable sheets until the remaining amount of toner reaches the first threshold as the remaining amount of toner decreases. The upper limit sheet number, which is a large number, is compared, and if it is determined that the scheduled print sheet number exceeds the upper limit sheet number before the update, it is determined that the remaining amount of toner reaches the first threshold during printing. .

  According to a sixth aspect of the present invention, in the image forming apparatus according to the second or third aspect, the determination unit includes a setting unit that allows a user to set the number of print copies, and a reading unit that reads image data of a document. By calculating the product of the dot count means for counting the number of dots of the image data read by the reading means, and the number of prints set by the setting means and the number of dots counted by the dot count means When the printing process is performed using dot number calculation means for calculating the number of dots of image data for the number of prints scheduled to be printed and the amount of toner obtained by subtracting the first threshold value from the second threshold value. An upper limit dot number storage means for storing an upper limit dot number with the total number of dots of the image formed on the paper as an initial value; An upper limit dot number updating unit for subtracting the dot number calculated by the dot number calculation unit from the upper limit dot number for each printing process until the first threshold value is reached, and updating the upper limit dot number; Until the remaining amount reaches the first threshold value until the first threshold value is reached, the upper limit dot number before the update process is updated by the upper limit dot number update unit and the dot number calculated by the dot number calculation unit And comparing means for determining whether the number of dots exceeds the upper limit number of dots, and the determination means is determined by the comparison means that the number of dots has exceeded the upper limit number of dots. In this case, it is determined that the remaining amount of toner reaches a first threshold during printing. According to this configuration, the number of dots is subtracted from the upper limit dot number for each printing process by the upper limit dot number update means until the remaining amount of toner reaches the first threshold value after reaching the second threshold value. Since the upper limit number of dots is updated, it is possible to determine the number of dots of an image that can be printed before the remaining amount of toner reaches the first threshold as the remaining amount of toner decreases. And the upper limit dot number that is the number of dots of the printable image are compared, and if it is determined that the dot number exceeds the upper limit dot number, the remaining amount of toner reaches the first threshold during printing. It is judged.

  An image forming apparatus according to a seventh aspect is the image forming apparatus according to any one of the first to sixth aspects, wherein the first toner remaining amount detecting means has a toner remaining amount equal to or less than a first threshold value. The display means displays a third message notifying that the single mode printing or the eco mode printing in which the normal mode printing based on the image data of the document is performed one by one on the recording paper can be selected. When the user selects the single mode printing in response to the message, the mode changing unit changes the print setting from the default eco mode printing to the single mode printing. According to this configuration, when the remaining toner amount is equal to or less than the first threshold by the first toner remaining amount detecting unit, the display unit performs normal mode printing based on the image data of the document on the recording paper. Displays that single-mode printing or eco-mode printing can be selected one by one, and when eco-mode printing is selected by the user's selection, eco-mode printing is performed, and single-shot printing mode is selected Paper sheets that have been printed in normal mode printing are output one by one. As a result, printing processing can be performed with an appropriate amount of toner depending on whether the user allows or does not allow a reduction in image quality of the printed matter while the amount of toner is limited.

  According to the image forming apparatus of the first aspect, when the toner remaining amount reaches the second threshold value, a message prompting the user to change to the eco mode printing is displayed by the display unit, and the eco mode printing is performed in response to the message. When the change is selected, eco-mode printing is performed. Therefore, it is possible to promote the eco-mode printing by informing the user in advance that the replacement time of the toner container is near and to promote eco-mode printing.

  According to the image forming apparatus of the second aspect, when the determination unit determines that the remaining amount of toner reaches the first threshold during printing, the display unit displays a message that prompts the user to change to the eco mode printing. When the change to eco-mode printing is selected in response to the message, eco-mode printing is performed.For example, when multi-copy printing is set immediately before the remaining amount of toner reaches the near end, It is possible to prevent the processing from being interrupted due to the remaining toner remaining. In addition, it is possible to prevent the image density from becoming nonuniform at the start and end of printing and to unify the image quality of the printed matter.

  According to the image forming apparatus of the third aspect, when the determination unit determines that the remaining amount of toner reaches the first threshold during printing, the print setting is automatically changed to the eco mode printing, and the eco mode printing is performed. Therefore, for example, when multi-copies printing is set immediately before the remaining amount of toner reaches the near end, the operation of changing the print setting by the user is omitted, and the remaining amount of toner is surely eliminated during printing. Can be prevented from being interrupted. In addition, it is possible to prevent the image density from becoming nonuniform at the start and end of printing and to unify the image quality of the printed matter.

  According to the image forming apparatus of the fourth aspect, the upper limit sheet number updating unit sequentially subtracts the print sheet number from the upper limit sheet number for each printing process until the remaining amount of toner reaches the first threshold value and reaches the first threshold value. Thus, as the remaining amount of toner decreases, the number of printable sheets until the remaining amount of toner reaches the first threshold value is obtained, and the comparison unit compares the planned number of prints with the upper limit number of printable sheets. When the scheduled number of prints exceeds the upper limit number, it can be determined that the remaining amount of toner reaches the first threshold during printing. That is, it is possible to determine whether or not the remaining amount of toner reaches the first threshold during printing with a simple configuration. Further, since the number of printed sheets, which is the number of sheets subjected to the printing process, is subtracted from the upper limit number, a highly accurate determination result can be obtained.

  According to the image forming apparatus of the fifth aspect, the upper limit number update unit sequentially calculates the planned number of prints from the upper limit number for each printing process until the remaining amount of toner reaches the first threshold value after reaching the second threshold value. By subtracting, the number of printable sheets is obtained until the remaining amount of toner reaches the first threshold as the remaining amount of toner decreases, and the comparison unit compares the planned number of prints with the upper limit number of printable sheets. When the scheduled number of prints exceeds the upper limit number, it can be determined that the remaining amount of toner reaches the first threshold during printing. That is, it is possible to determine whether or not the remaining amount of toner reaches the first threshold during printing with a simpler configuration without requiring a means for detecting the number of printed sheets such as a print counting means.

  According to the image forming apparatus of the sixth aspect, the upper limit dot number updating unit sequentially changes the upper limit dot number to the dot number for each printing process from when the remaining amount of toner reaches the first threshold value until the first threshold value is reached. Is subtracted to obtain the number of dots of an image that can be printed until the remaining amount of toner reaches the first threshold as the remaining amount of toner decreases, and the comparing means compares the number of dots with the upper limit number of dots. When the number of dots exceeds the upper limit number of dots, it can be determined that the remaining amount of toner reaches the first threshold during printing. That is, it is possible to accurately determine whether or not the remaining amount of toner reaches the first threshold during printing in consideration of a difference in toner usage due to a difference in image density of the document.

  According to the image forming apparatus of the seventh aspect, when the toner remaining amount is equal to or less than the first threshold by the first toner remaining amount detecting unit, the display unit selects the single mode printing or the eco mode printing. Appropriate amount of toner depending on whether or not the user is allowed to reduce the image quality of the printed matter while the amount of toner is limited, because the print processing in the selected mode is displayed The printing process can be performed.

(First embodiment)
Hereinafter, a copying machine according to an embodiment of the present invention will be described as an example of an image forming apparatus according to the present invention with reference to the drawings. FIG. 1 is a schematic side view mainly showing a mechanical configuration of a copying machine according to an embodiment of the present invention.

  The copying machine 1 includes a main body unit 200, a paper post-processing unit 300 disposed on the paper carry-out side, for example, the left side of the main body unit 200, an operation unit 400 for a user to input various operation commands and the like, The document reading unit 500 is disposed at the top of the unit 200, and the document feeding unit 600 is disposed at the top of the document reading unit 500.

  The document feeding unit 600 includes a document storage unit 601, a document discharge unit 602, a paper feed roller 603, a document count unit 604, and the like, and the document reading unit 500 includes a scanner 501 and the like. A paper feed roller 603 feeds a document set in the document storage unit 601, and transports the document one by one on the scanner 501 one by one by a transport roller (not shown). A document count unit 604 feeds a document fed by the paper feed roller 603. Count sequentially. The scanner 501 sequentially reads the conveyed document, and the read document is discharged to the document discharge unit 602.

  The operation unit 400 includes a touch panel 401, a start key 402, a numeric keypad 403, and the like. The touch panel 401 displays various operation screens and various operation buttons for the user to input various operation commands. The start key 402 is used for the user to input a print execution command and the like, and the ten key 403 is used for inputting the number of prints and the like.

  The main body 200 includes a plurality of paper feeding cassettes 201, a plurality of paper feeding rollers 202, a transfer roller 203, a photosensitive drum 204, an exposure device 206, a black developing device 207, a fixing roller 208, and a discharge port 209.

  The photosensitive drum 204 is uniformly charged by a charging device (not shown) while rotating in the direction of the arrow. The exposure device 206 scans the photosensitive drum 204 with laser light modulated according to the image data of the document read by the document reading unit 500, and forms an electrostatic latent image on the drum surface. The developing device 207 includes a toner container having a black developer (toner), and supplies toner to the photosensitive drum 204 to form a toner image.

  On the other hand, the paper feed roller 202 pulls out the recording paper from the paper feed cassette 201 in which the recording paper is stored, and feeds the recording paper to the transfer roller 203. The transfer roller 203 transfers the toner image on the photosensitive drum 204 to the conveyed recording paper, and the fixing roller 208 heats and transfers the transferred toner image to the recording paper. Thereafter, the recording paper on which the printing process has been performed is carried into the paper post-processing section 300 from the discharge port 209 of the main body section 200.

  The paper post-processing unit 300 includes a carry-in port 301, a recording paper carrying unit 302, a carry-out port 303, a stack tray 304, a print count unit 305, and the like. The recording paper transport unit 302 sequentially transports the recording paper carried into the carry-in port 301 from the discharge port 209 and finally ejects the recording paper from the carry-out port 303 to the stack tray 304. The stack tray 304 is configured to move up and down in the direction of the arrow in accordance with the number of recording sheets stacked from the carry-out port 303. The print count unit 305 is installed at an appropriate position of the apparatus, for example, near the discharge port 303, and counts the number of recording sheets discharged from the discharge port 303.

  FIG. 2 is a control block diagram of the copying machine shown in FIG. The copying machine 1 includes a scanner unit 11, an image processing unit 21, a printer unit 31, a control unit 41, an operation panel unit 51, and an HDD (hard disk drive) 74.

  The operation panel unit 51 includes a touch panel unit 52 including the touch panel 401 shown in FIG. 1 and an operation key unit 53 including the start key 402 and the numeric keypad 403 shown in FIG. The touch panel unit 52 includes a touch panel unit or the like that combines a touch panel and an LCD (Liquid Crystal Display). The touch panel unit 52 displays various operation screens and allows the user to input various operation commands by touching the part. Displays the operation buttons. The operation key unit 53 is used for a user to input a print execution command or the like.

  The scanner unit 11 includes an exposure lamp 12 and a CCD (charge coupled device) 13 that constitute the scanner 501 shown in FIG. The scanner unit 11 irradiates the original with the exposure lamp 12 and receives the reflected light with the CCD 13, thereby reading the original image and outputting image data corresponding to the read image to the image processing unit 21.

  The image processing unit 21 includes a correction unit 22, an image processing unit 23, and an image memory 24. The image processing unit 21 processes the read image data by the correction unit 22 and the image processing unit 23 as necessary, and stores the processed image data in the image memory 24 or outputs the processed image data to the printer unit 31. The correction unit 22 performs predetermined correction processing such as level correction and γ correction on the read image data. The image processing unit 23 performs various types of processing such as image data compression or expansion processing and enlargement or reduction processing.

  The printer unit 31 is an image composed of a paper transport unit 32 composed of the paper feed cassette 201 and paper feed roller 202 shown in FIG. 1, the photoconductive drum 204, the exposure device 206 and the development device 207 shown in FIG. The image forming apparatus includes a forming unit 33, a transfer unit 34 including the transfer roller 203 shown in FIG. 1, and a fixing unit 35 including the fixing roller 208 shown in FIG. The printer unit 31 prints document data read by the scanner unit 11 on recording paper. Specifically, the paper transport unit 32 transports the recording paper to the image forming unit 33, the image forming unit 33 forms a toner image corresponding to the image data, and the transfer unit 34 transfers the toner image to the recording paper. The fixing unit 35 fixes the toner image on the recording paper to form an image.

  The HDD 74 stores image data read by the scanner unit 11, an output format set for the image data, and the like. The control unit 41 includes a CPU (Central Processing Unit) 42, a ROM (Read Only Memory) 43 that stores various program data executed by the CPU 42, a RAM (Random Access Memory) 44 as a work area of the CPU 42, and the like. And control each part of the apparatus. That is, the control unit 41 includes a computer. The program data can be supplied through a recording medium such as a ROM or a CD-ROM, or can be provided through a transmission medium such as a network.

  FIG. 3 is a block diagram showing a detailed configuration of the control unit 41 shown in FIG. The toner container 8 has a toner remaining amount detection sensor 81 that detects whether or not the toner remaining amount in the toner container 8 exceeds a first threshold that is a criterion for determining whether or not the toner remaining amount is “near end”. (First toner remaining amount detecting means) and a toner remaining amount detecting sensor 82 (second toner remaining amount detecting means) for detecting whether the toner remaining amount exceeds a second threshold value greater than the first threshold value. Have Here, the second threshold value is set to, for example, 1/3 of the total amount of toner contained in the unused toner container 8. The toner remaining amount detection sensors 81 and 82 are, for example, transmissive sensors composed of a light emitting element and a light receiving element. The toner container 8 is turned off when shielded by the toner in the toner container 8 and is turned on when not shielded. Installed inside or outside. When the toner remaining amount detection sensors 81 and 82 are installed outside the toner container 8, at least a part of the toner container 8 located in the optical path from the light emitting element to the light receiving element is preferably made of a transparent material. The toner remaining amount detection sensor 81 outputs an off signal when the remaining amount of toner exceeds the first threshold value, and outputs an on signal when the remaining amount of toner is equal to or less than the first threshold value. Installed. The toner remaining amount detection sensor 82 outputs an off signal when the remaining amount of toner exceeds the second threshold value, and outputs an on signal when the remaining amount of toner is equal to or less than the second threshold value. Installed. Although a transmission type sensor is used here, any other means such as a means for detecting torque when the toner in the toner container 8 is agitated by an agitator or the like is adopted as a means for detecting the remaining amount of toner. Also good.

  The control unit 41 includes a remaining toner amount detection unit 411, a print number calculation unit 412, a comparison unit 413, an upper limit number change unit 414, a mode setting unit 415, a display control unit 416, and an upper limit number storage unit 417. Based on the output signals from the toner remaining amount detection sensors 81 and 82, the toner remaining amount detecting unit 411 exceeds the first threshold by setting the remaining amount of toner in the toner container 8 to the “multiple” level exceeding the second threshold. Detection is performed in three stages: a “medium” level that is less than or equal to a threshold of 2 and a “low” level that is less than or equal to a first threshold. Specifically, when the output signal from the toner remaining amount detection sensor 82 is an off signal, the toner remaining amount detection unit 411 has a multi-level toner remaining amount, and the output signal from the toner remaining amount detection sensor 82 Is an ON signal and the output signal from the toner remaining amount detection sensor 81 is an OFF signal, the remaining amount of toner is at a medium level, and both output signals from the remaining toner detection sensors 81 and 82 are ON signals. If it is, it is detected that the remaining amount of toner is low.

  The number-of-prints calculation unit 412 (corresponding to a specific example of the calculation unit of the present invention) starts operation when the remaining amount of toner detected by the remaining toner amount detection unit 411 reaches a medium level, and every time printing processing is performed. For example, the number of documents counted by the document counting unit 604 (corresponding to a specific example of the document counting unit of the present invention) installed in the document feeding unit 600 and the number of copies set by the operation panel unit 51 (setting unit). Is calculated, and the expected number of prints to be printed is calculated. In an upper limit sheet storage unit 417 (corresponding to a specific example of the upper limit sheet storage means of the present invention), the number of sheets that can be printed with a toner amount obtained by subtracting the first threshold value from the second threshold value is a default value (initial value). Is stored, and here, 1000 is stored as the default value. The upper limit sheet number changing unit 414 (corresponding to a specific example of the upper limit sheet number updating unit of the present invention) performs printing processing when the remaining toner amount detected by the remaining toner amount detecting unit 411 is medium level. Each time the number of prints counted by the print count unit 305 is subtracted from the upper limit number stored in the upper limit number storage unit 417, the number of printable sheets is updated until the remaining amount of toner reaches a low level.

  The comparison unit 413 (corresponding to a specific example of the comparison unit of the present invention) performs an operation for starting printing by the operation panel 51 when the toner remaining amount detected by the toner remaining amount detection unit 411 is at a medium level. When this is done, the scheduled number of prints calculated by the number-of-prints calculation unit 412 is compared with the upper limit number stored in the upper limit number storage unit 417. If the expected print number is less than or equal to the upper limit number, it is set. When it is determined that the remaining amount of toner remains at the medium level when the printing process is completed, and the planned number of prints exceeds the upper limit, the toner is being processed while the set print process is being performed. It is determined that the remaining amount reaches a low level.

  The mode setting unit 415 (mode changing unit) normally performs printing processing with the default setting of printing with a normal toner consumption amount when the toner remaining amount detected by the toner remaining amount detecting unit 411 is multilevel or medium level. In addition to setting to mode printing, it is set to a state that can be switched to eco-mode printing by user selection. In addition, when the remaining amount of toner detected by the remaining toner amount detecting unit 411 is a low level, the mode setting unit 415 sets the default setting to eco mode printing and presses the start key 402 according to the user's selection. In conjunction with this, it is set in a state where it can be switched to single mode printing in which sheets printed in normal mode printing are output one by one. The display control unit 416 has data related to the screen content displayed on the touch panel unit 52 (display unit) of the operation panel unit 51, and displays a screen corresponding to an operation instruction from the user.

  When eco-mode printing is set by the mode setting unit 415, thinning processing is performed by the image processing unit 23 to reduce the number of dots constituting the image read by the scanner unit 11, and based on the image data after the thinning processing. Continuous printing is performed. Here, in order to reduce the toner consumption, a part of the data is thinned out from the image data of the document. However, the present invention is not limited to this. For example, a method for printing only the outline of a character or a photosensitive drum. A method of reducing the amount of toner by reducing the output of the laser beam to be irradiated may be adopted.

  4 and 5 are flowcharts for explaining the processing of the control unit.

  In step S1, it is determined whether or not the start key 402 has been pressed. If the start key 402 has been pressed, it is determined that printing conditions such as the number of copies and the magnification have been set, and the process proceeds to step S3, where the document Documents set in the storage unit 601 are conveyed one by one to the reading position of the scanner 501 one by one by a paper feed roller 603, and image data of the document is read, and at the same time, the document count unit 604 counts the number of documents.

  In step S <b> 5, the toner remaining amount detection unit 411 determines whether the remaining amount of toner exceeds the second threshold based on the remaining amount detection signal that is an output signal from the remaining toner amount detection sensor 82. If the detection signal is off, it is determined that the remaining amount of toner exceeds the second threshold, and the process proceeds to step S9. If the remaining amount detection signal is on, the remaining amount of toner is equal to or less than the second threshold. The process proceeds to step S13. In step S9, normal mode printing is started. In step S11, it is determined whether the printing process has been completed. If it is determined that the printing process has been completed, the process ends.

  In step S <b> 13, the toner remaining amount detecting unit 411 determines whether the remaining amount of toner exceeds the first threshold based on the remaining amount detection signal that is an output signal from the remaining toner amount detecting sensor 81. If the detection signal is off, it is determined that the remaining amount of toner exceeds the first threshold, and the process proceeds to step S15. In step S <b> 15, the print number calculation unit 412 obtains the planned print number by obtaining the product of the number of documents counted by the document count unit 604 and the number of prints set by the operation panel unit 51. In step S <b> 17, the comparison unit 413 determines whether or not the scheduled print number obtained by the print number calculation unit 412 exceeds the upper limit number stored in the upper limit number storage unit 417. If YES, the process proceeds to step S19. In step S <b> 19, the touch panel unit 52 displays an eco mode printing guide screen for prompting the user to perform eco mode printing. FIG. 6 is a diagram showing an example of the eco-mode printing guide screen displayed on the touch panel unit 52. For example, the screen G1 displays “Toner remaining amount is less than 1/3. Eco-mode printing is performed. Is displayed, and an “OK” key K1 and a “No” key K2 for affirming or denying the message are displayed.

  If the No key K2 on the eco-mode printing guide screen G1 is pressed in step S23, the process proceeds to step 25, and normal mode printing is performed. If the OK key K1 is pressed, the process proceeds to step S27, and mode setting is performed. The printing setting is switched to eco-mode printing by unit 415, and eco-mode printing is performed in step S29. In step S31, when the sheet is discharged from the discharge port 305, the print count unit 305 counts the number of printed sheets. In step S33, it is determined whether or not the printing process has been completed. Returns to step S31, and continues the count process until the print process is completed (Yes in step S33), thereby obtaining the total number of prints for which the print process has been performed. In step S <b> 35, the upper limit sheet number changing unit 414 updates the upper limit sheet number by subtracting the print sheet number counted by the print count unit 305 from the upper limit sheet number stored in the upper limit sheet number storage unit 417.

  On the other hand, if the scheduled print number exceeds the upper limit number in step S17, it is determined that there is no toner remaining during the set printing process, and the process proceeds to step S21, where the touch panel unit 52 performs eco-mode printing. An eco-mode printing guidance screen G2 having a content different from that of the guidance screen G1 is displayed. FIG. 7 is a diagram showing an example of an eco-mode printing guide screen displayed on the touch panel unit 52. For example, a message “Toner runs out during printing. Do you want to perform eco-mode printing?” Is displayed on the screen G2. Is displayed, and “OK” key K3 and “No” key K4 for affirming or denying the message are displayed.

  In step S23, if the No key K4 on the eco-mode printing guide screen G2 is pressed, the process proceeds to step 25, and normal mode printing is performed. If the OK key K3 is pressed, the process proceeds to step S27, and mode setting is performed. The printing setting is switched to eco-mode printing by unit 415, and eco-mode printing is performed in step S29. In step S31, when the sheet is discharged from the discharge port 305, the print count unit 305 counts the number of printed sheets. In step S33, it is determined whether or not the printing process has been completed. Returns to step S31, and continues the count process until the print process is completed (No in step S33), thereby obtaining the total number of prints on which the print process has been performed. In step S <b> 35, the upper limit sheet number changing unit 414 updates the upper limit sheet number by subtracting the print sheet number counted by the print count unit 305 from the upper limit sheet number stored in the upper limit sheet number storage unit 417.

  In step S13, if the remaining amount detection signal from the toner remaining amount detection sensor 81 is on, the toner remaining amount detecting unit 411 determines that the remaining amount of toner is equal to or less than the first threshold, and proceeds to step S37. The mode setting unit 415 switches the default print processing setting from normal mode printing to eco mode printing. In step S39, the touch panel unit 52 displays a toner replacement guidance screen for prompting the user to replace the toner container 8. FIG. 8 is a view showing an example of a toner replacement guidance screen displayed on the touch panel unit 52. For example, the screen G3 displays “Toner is out. Please replenish toner. The message “Printing or single mode printing” is displayed, and “Eco mode printing” key K5 for selecting eco mode printing and “Single mode printing” key K6 for selecting single mode printing are displayed. Is displayed.

  In step S41, it is determined whether or not the toner container 8 has been replaced or the eco-mode print key K5 or the single-shot mode print key K6 has been pressed. When the eco mode print key K5 is pressed, the process proceeds to step S43, and eco mode printing is performed. In step S45, it is determined whether or not the printing process has ended. If it is determined that the printing process has ended, the process ends. If the toner container 8 has been replaced, the process proceeds to step S57, where the mode setting unit 415 switches the print setting from the eco mode printing to the normal printing mode, and proceeds to step S59, where normal mode printing is performed. In step S61, it is determined whether the printing process has been completed. If it is determined that the printing process has been completed, the process ends.

  When the single mode printing key K6 is pressed, the process proceeds to step S47, and the mode setting unit 415 switches the setting from the eco mode printing to the single mode printing. In step S <b> 49, the touch panel unit 52 displays a single mode print guide screen for guiding the single mode print operation to the user. FIG. 9 is a diagram showing an example of a single mode printing guide screen displayed on the touch panel unit 52. For example, a message “Please press the start key when performing single mode printing” is displayed on the screen G4. And a “return” key K7 for switching the screen G4 to the previous screen G3. In step S51, it is determined whether or not the start key 402 is pressed. When the start key 402 is pressed, the process proceeds to step S53, and single mode printing is performed. In step S55, it is determined whether or not the printing process has been completed by printing all the sheets. If it is determined that the printing process has not ended, the process returns to step S51. If it is determined that the printing process has ended, End the process.

  As described above, according to the present exemplary embodiment, the remaining amount detection signal received from the remaining toner amount detection sensors 81 and 82 determines whether the remaining amount of toner is high, medium, or low level. After that, when an operation for starting the printing process is performed by the operation panel unit 51, the eco-mode printing guide screen G1 for prompting the eco-mode printing is displayed on the touch panel unit 52, so that the eco-mode printing is performed. The amount of toner consumption can be reduced.

  Also, when the remaining amount of toner reaches a medium level, the estimated number of prints is calculated at the start of the printing process, and the planned number of prints is compared with the maximum number of sheets that can be printed before the remaining amount of toner reaches a low level. If the scheduled number exceeds the upper limit number, it is determined that the toner runs out during printing, and an eco-mode printing guide screen G2 for informing that and prompting eco-mode printing is displayed on the touch panel unit 52. Thus, when eco-mode printing is selected, eco-mode printing is performed on the image data of all originals, and normal mode printing is switched to eco-mode printing during printing as in the past, resulting in non-uniform image density. This can be prevented. Further, since the toner consumption is saved by eco-mode printing, it is possible to prevent interruption of processing due to the remaining toner remaining during printing.

  In the process of FIG. 4, if “No” is determined in step S17, the process proceeds to step S25 without performing the process in step S19, and printing is performed in the default normal print mode. May be. Even in this case, when it is determined that the toner runs out during printing, the eco-mode printing guide screen G2 is displayed, and the user can select the eco-mode printing according to this. It is possible to prevent the processing from being interrupted due to switching from printing to eco-mode printing or running out of remaining toner during printing.

(Second Embodiment)
Next, an image forming apparatus according to a second embodiment of the present invention will be described with reference to the drawings. Note that the mechanical configuration and electrical configuration of the entire copying machine 1 are the same as those in FIGS. 1 and 2, so refer to FIGS. 1 and 2. FIG. 10 is a block diagram showing a detailed configuration of the control unit 41 shown in FIG. In the figure, the same reference numerals as those in FIG. 3 are the same or corresponding parts, and the description thereof is omitted.

  The dot count unit 450 (dot count unit) starts operation when the toner remaining amount detected by the toner remaining amount detection unit 411 reaches a medium level. When the printing process starts, the scanner unit 11 (reading unit) causes all the originals to be scanned. When the image data is read and stored in the image memory 24, the number of dots of the image data of the document is counted. The dot number calculation unit 451 (dot number calculation means) obtains the product of the number of dots counted by the dot count unit 450 and the number of prints set by the operation panel unit 51, and images for the scheduled number of prints to be printed. Calculate the number of dots in the data. The upper limit dot number storage unit 454 (upper limit dot number storage means) uses a toner of an amount obtained by subtracting the first threshold value from the second threshold value, and recording paper when normal mode printing, which is an example of print processing, is performed. The upper limit number of dots whose initial value is a value corresponding to the number of dots of the image formed in the above is stored. The upper limit dot number changing unit 453 (upper limit dot number updating unit) performs an upper limit dot number storage unit 454 each time print processing is performed when the toner remaining amount detected by the toner remaining amount detection unit 411 is at a medium level. The number of dots calculated by the dot number calculation unit 451 is subtracted from the upper limit number of dots stored in, and the number of dots of an image that can be printed before the remaining amount of toner reaches a low level is obtained. The comparison unit 452 (comparison unit) calculates the number of dots each time an operation for starting printing is performed by the operation panel 51 when the toner remaining amount detected by the toner remaining amount detection unit 411 is a medium level. When the number of dots calculated by the unit 451 is compared with the upper limit dot number stored in the upper limit dot number storage unit 454 and the dot number is less than or equal to the upper limit dot number, the set print processing is completed. It is determined that the remaining amount of toner remains at the medium level, and if the number of dots exceeds the upper limit number of dots, the remaining amount of toner reaches a low level during the set printing process. to decide.

  11 and 12 are flowcharts for explaining the processing of the control unit.

  In step S1, it is determined whether or not the start key 402 has been pressed. If the start key 402 has been pressed, it is determined that printing conditions such as the number of copies and the magnification have been set, and the process proceeds to step S3, where the document Documents set in the storage unit 601 are sequentially conveyed one by one to the reading position of the scanner 501 by the feed roller 603, image data of the document is read by the scanner 501, and the read image data is stored in the image memory 24. The In step S <b> 5, the toner remaining amount detection unit 411 determines whether the remaining amount of toner exceeds the second threshold based on the remaining amount detection signal that is an output signal from the remaining toner amount detection sensor 82. If the detection signal is off, it is determined that the remaining amount of toner exceeds the second threshold, and the process proceeds to step S9. If the remaining amount detection signal is on, the remaining amount of toner is equal to or less than the second threshold. The process proceeds to step S13. In step S9, normal mode printing is started. In step S11, it is determined whether the printing process has been completed. If it is determined that the printing process has been completed, the process ends.

  In step S <b> 13, the toner remaining amount detecting unit 411 determines whether the remaining amount of toner exceeds the first threshold based on the remaining amount detection signal that is an output signal from the remaining toner amount detecting sensor 81. If the detection signal is off, it is determined that the remaining amount of toner exceeds the first threshold value, and the process proceeds to step S101. In step S <b> 101, the dot count unit 450 counts the number of dots in the document image data stored in the image memory 24. In step S <b> 102, the dot number calculation unit 451 calculates the product of the counted number of dots and the number of prints set by the operation panel unit 51, and calculates the number of dots of image data corresponding to the scheduled print number. . In step S103, the comparison unit 452 determines whether the dot number obtained by the dot number calculation unit 451 exceeds the upper limit dot number stored in the upper limit dot number storage unit 454, and the dot number is the upper limit dot number. If it is the following, the process proceeds to step S105. In step S <b> 105, the touch panel unit 52 displays an eco mode printing guide screen for prompting the user to perform eco mode printing. Since the contents of the eco-mode printing guide screen are the same as those in FIG. 6, refer to FIG. On the screen G1, for example, a message “Toner remaining amount is 1/3 or less. Do you want to perform eco-mode printing?” And “OK” for affirming or denying the message is displayed. The key K1 and the “No” key K2 are displayed.

  In step S109, when the No key K2 on the eco-mode printing guide screen G1 is pressed, the process proceeds to step 111, and normal mode printing is performed. In step S113, it is determined whether the printing process has been completed. If it is determined that the printing process has been completed, the process proceeds to step S121. In step S121, the upper limit dot number changing unit 453 updates the upper limit dot number by subtracting the dot number calculated by the dot number calculation unit 451 from the upper limit dot number stored in the upper limit dot number storage unit 454. On the other hand, if the OK key K1 on the eco-mode printing guidance screen G1 is pressed, the process proceeds to step S115, where the mode setting unit 415 switches the print setting to eco-mode printing, and eco-mode printing is performed in step S117. In step S119, it is determined whether the printing process has been completed. If it is determined that the printing process has been completed, the process proceeds to step S121. In step S121, the upper limit dot number changing unit 453 updates the upper limit dot number by subtracting the dot number calculated by the dot number calculation unit 451 from the upper limit dot number stored in the upper limit dot number storage unit 454.

  On the other hand, if the number of dots exceeds the upper limit number of dots in step S103, it is determined that there is no toner remaining during the set printing process, and the process proceeds to step S107, where the touch panel unit 52 performs eco-mode printing. An eco-mode printing guidance screen G2 having a content different from that of the guidance screen G1 is displayed. Since the contents of the eco-mode printing guide screen G2 are the same as those in FIG. 7, reference is made to FIG. For example, a message “Toner runs out during printing. Do you want to perform eco-mode printing?” Is displayed on the screen G2, and an “OK” key K3 and “No” are used to confirm or deny the message. ”Key K4 is displayed.

  In step S109, when the No key K4 on the eco-mode printing guide screen G2 is pressed, the process proceeds to step 111, and normal mode printing is performed. In step S113, it is determined whether the printing process has been completed. If it is determined that the printing process has been completed, the process proceeds to step S121. In step S121, the upper limit dot number changing unit 453 updates the upper limit dot number by subtracting the dot number calculated by the dot number calculation unit 451 from the upper limit dot number stored in the upper limit dot number storage unit 454. On the other hand, if the OK key K3 on the eco-mode printing guide screen G2 is pressed, the process proceeds to step S115, where the mode setting unit 415 switches the print setting to eco-mode printing, and eco-mode printing is performed in step S117. In step S119, it is determined whether the printing process has been completed. If it is determined that the printing process has been completed, the process proceeds to step S121. In step S121, the upper limit dot number changing unit 453 updates the upper limit dot number by subtracting the dot number calculated by the dot number calculation unit 451 from the upper limit dot number stored in the upper limit dot number storage unit 454. The following processing is performed in the same manner as steps S37 to S61 in FIG.

  As described above, according to the present exemplary embodiment, the remaining amount detection signal received from the remaining toner amount detection sensors 81 and 82 determines whether the remaining amount of toner is high, medium, or low level. After that, when an operation for starting the printing process is performed by the operation panel unit 51, the eco-mode printing guide screen G1 for prompting the eco-mode printing is displayed on the touch panel unit 52, so that the eco-mode printing is performed. The amount of toner consumption can be reduced. When the remaining amount of toner reaches a medium level, the number of dots is counted from the image data of the document at the start of the printing process, and the upper limit dot indicating the number of dots and the number of dots of an image that can be printed before the remaining amount of toner reaches a low level If the number of dots exceeds the upper limit number of dots, it is determined that the toner runs out during printing, and an eco-mode printing guide screen G2 that informs that fact and prompts eco-mode printing is displayed on the touch panel unit 52. . Accordingly, it is possible to accurately determine whether or not the remaining amount of toner reaches the first threshold during printing in consideration of a difference in toner usage due to a difference in image density of the document. In addition, when eco-mode printing is selected, eco-mode printing is performed on the image data of all originals, and normal mode printing is switched to eco-mode printing during printing as in the past, resulting in non-uniform image density. Can be prevented. Furthermore, since the toner consumption is saved by eco-mode printing, it is possible to prevent the processing from being interrupted due to the remaining toner remaining during printing.

(Other embodiments)
In the first embodiment, the upper limit sheet number changing unit 414 subtracts the number of printed sheets counted by the print count unit 305 from the upper limit number stored in the upper limit sheet number storing unit 417 for each printing process, so that the remaining toner amount is obtained. However, the present invention is not limited to this, and the scheduled print number calculated by the print number calculation unit 412 is subtracted from the upper limit number stored in the upper limit number storage unit 417 for each printing process. Thus, the upper limit number may be updated. In this case, the comparison unit 413 compares the upper limit sheet number before being updated by the upper limit sheet number changing unit 414 with respect to the set print processing, and the print sheet number calculated by the print sheet number calculation unit 413, thereby performing toner during printing. It can be determined whether the remaining amount reaches the first threshold.

  In the first embodiment, the upper limit sheet number obtained by subtracting the first threshold value from the second threshold value and converted into the print sheet number is updated for each printing process, and when the scheduled print sheet number exceeds the upper limit sheet number. Although the timing at which the remaining amount of toner reaches a low level is detected, the number of printed sheets counted by the print count unit 305 is added for each printing process, and the remaining amount of toner is reached when the total value exceeds the upper limit number. It may be determined that has reached a small level.

  In the first and second embodiments, the remaining toner amount detection unit 411 increases the remaining amount of toner in the toner container 8 based on the remaining amount detection signal received from the remaining toner amount detection sensors 81 and 82. Although it is discriminated in three stages of low levels, the number of remaining toner detection sensors is increased, the remaining amount of toner is detected more accurately, and a message corresponding to the remaining amount of toner is displayed on the touch panel unit 401. Also good.

  In the first and second embodiments, when it is determined that the remaining amount of toner reaches a low level during printing before the start of printing, a guidance screen including a message prompting eco-mode printing is displayed on the touch panel unit 401, and the user Employs a manual selection method that switches the print setting from normal mode printing to eco mode printing when eco mode printing is selected, but when it is determined that the toner level reaches a low level during printing, You may employ | adopt the automatic control system which performs control which switches mode printing to eco-mode printing automatically.

  In the first and second embodiments, the copying machine 1 is used as an example of an image forming apparatus. However, the present invention can also be applied to a printer. A guidance screen for guiding the mode may be displayed on a monitor of a PC (personal computer) connected to the printer.

1 is a schematic side view mainly showing a configuration of a copying machine according to first and second embodiments of the present invention. FIG. 3 is a control block diagram of a copying machine according to first and second embodiments of the present invention. It is a block diagram which shows the detailed structure of the control part by the 1st Embodiment of this invention. It is a flowchart for demonstrating the process of the control part by the 1st Embodiment of this invention. It is a flowchart for demonstrating the process of the control part by the 1st Embodiment of this invention. In the 1st and 2nd embodiment of the present invention, it is a figure showing an example of the eco mode printing guidance screen displayed on a touch panel part. In the 1st and 2nd embodiment of the present invention, it is a figure showing an example of the eco mode printing guidance screen displayed on a touch panel part. FIG. 6 is a diagram illustrating an example of a toner replacement guidance screen displayed on a touch panel unit in the first and second embodiments of the present invention. In the 1st and 2nd embodiment of the present invention, it is a figure showing an example of the single mode printing guidance screen displayed on a touch panel part. It is a block diagram which shows the detailed structure of the control part by the 2nd Embodiment of this invention. It is a flowchart for demonstrating the process of the control part by the 2nd Embodiment of this invention. It is a flowchart for demonstrating the process of the control part by the 2nd Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Copier 8 Toner container 21 Image processing part 23 Image processing part 24 Image memory 41 Control part 51 Operation panel part 81 Toner remaining amount detection sensor 82 Toner remaining amount detection sensor 305 Print count part 411 Toner remaining amount detection part 412 Calculation of the number of printed sheets Unit 413, 451 comparison unit 414 upper limit number change unit 415 mode setting unit 416 display control unit 417 upper limit number storage unit 450 dot count unit 451 dot number calculation unit 452 comparison unit 453 upper limit dot number change unit 454 upper limit dot number storage unit 604 document Counter section

Claims (7)

A main body that forms an image corresponding to image data on a sheet, a replaceable toner container enclosing toner used for image formation, and whether or not the remaining amount of toner contained in the toner container exceeds a first threshold value If the first toner remaining amount detecting means for detecting whether the toner remaining amount exceeds the first threshold value, printing is performed with a normal set amount of toner. Default print settings are set for normal mode printing, and if it is determined that the remaining amount of toner is less than or equal to the first threshold, the default print settings are set for eco mode printing that reduces the amount of toner used compared to normal mode printing. An image forming apparatus comprising mode change means,
Second toner remaining amount detecting means for detecting whether or not the remaining amount of toner exceeds a second threshold greater than a first threshold;
If the remaining amount of toner exceeds the first threshold value and is equal to or less than the second threshold value by the first and second toner remaining amount detecting means, it is urged to change the print setting from normal mode printing to eco mode printing. Display means for displaying a first message,
When the user selects a change to eco-mode printing in response to the first message, the mode changing unit changes the print setting from normal mode printing set as default to eco-mode printing. Image forming apparatus. A main body that forms an image corresponding to image data on a sheet, a replaceable toner container enclosing toner used for image formation, and whether or not the remaining amount of toner contained in the toner container exceeds a first threshold value If the first toner remaining amount detecting means for detecting whether the toner remaining amount exceeds the first threshold value, printing is performed with a normal set amount of toner. Default print settings are set for normal mode printing, and if it is determined that the remaining amount of toner is less than or equal to the first threshold, the default print settings are set for eco mode printing that reduces the amount of toner used compared to normal mode printing. An image forming apparatus comprising mode change means,
Second toner remaining amount detecting means for detecting whether or not the remaining amount of toner exceeds a second threshold greater than a first threshold;
Whether or not the remaining amount of toner reaches the first threshold value during printing when the remaining toner amount exceeds the first threshold value and is equal to or less than the second threshold value by the first and second remaining toner amount detecting means. Determining means for determining before printing starts,
Display means for displaying a second message that prompts the user to change the print setting from normal mode printing to eco-mode printing when the determination means determines that the remaining amount of toner reaches the first threshold during printing; With
When the user selects a change to eco-mode printing in response to the second message, the mode changing unit changes the print setting from normal mode printing set as default to eco-mode printing. Image forming apparatus. A main body that forms an image corresponding to image data on a sheet, a replaceable toner container enclosing toner used for image formation, and whether or not the remaining amount of toner contained in the toner container exceeds a first threshold value If the first toner remaining amount detecting means for detecting whether the toner remaining amount exceeds the first threshold value, printing is performed with a normal set amount of toner. Default print settings are set for normal mode printing, and if it is determined that the remaining amount of toner is less than or equal to the first threshold, the default print settings are set for eco mode printing that reduces the amount of toner used compared to normal mode printing. An image forming apparatus comprising mode change means,
Second toner remaining amount detecting means for detecting whether or not the remaining amount of toner exceeds a second threshold greater than a first threshold;
Whether or not the remaining amount of toner reaches the first threshold value during printing when the remaining toner amount exceeds the first threshold value and is equal to or less than the second threshold value by the first and second remaining toner amount detecting means. Determining means for determining before printing starts,
When the determination unit determines that the remaining amount of toner reaches the first threshold during printing, the mode change unit changes the print setting from normal mode printing set as default to eco mode printing. An image forming apparatus. The determination means includes
Setting means for enabling the user to set the number of copies;
A document counting means for counting the number of documents,
A calculating means for calculating a planned number of prints to be printed by calculating a product of the number of originals counted by the original counting means and the number of copies set by the setting means;
An upper limit number storage unit that stores an upper limit number of sheets that has an initial value of the number of printable sheets after the remaining amount of toner reaches the first threshold value;
A print counting means for counting the number of printed sheets, which is the number of print processes,
Upper limit sheet number update means for subtracting the number of print sheets from the upper limit sheet number for each printing process until the remaining amount of toner reaches the first threshold value, and updating the upper limit sheet number;
The upper limit number stored in the upper limit number storage unit is compared with the scheduled print number calculated by the calculation unit until the remaining amount of toner reaches the first threshold value after reaching the second threshold value. Comparing means for determining whether the planned number of prints exceeds the upper limit number,
4. The determination unit according to claim 2, wherein the determination unit determines that the remaining amount of toner reaches a first threshold during printing when the comparison unit determines that the scheduled printing number exceeds the upper limit number. 5. The image forming apparatus described. The determination means includes
Setting means for enabling the user to set the number of copies;
A document counting means for counting the number of documents,
A calculating means for calculating a planned number of prints to be printed by calculating a product of the number of originals counted by the original counting means and the number of copies set by the setting means;
An upper limit number storage unit that stores an upper limit number of sheets that has an initial value of the number of printable sheets after the remaining amount of toner reaches the first threshold value;
An upper limit sheet number update means for subtracting the scheduled print sheet number from the upper limit sheet number for each printing process until the remaining amount of toner reaches the first threshold value, and updating the upper limit sheet number;
Until the remaining amount of toner reaches the first threshold value until the first threshold value is reached, the upper limit number of sheets for the current printing process before being updated by the upper limit number update unit, the scheduled print number calculated by the calculation unit, and Comparing means for determining whether or not the scheduled number of prints exceeds the upper limit number,
4. The determination unit according to claim 2, wherein the determination unit determines that the remaining amount of toner reaches a first threshold during printing when the comparison unit determines that the scheduled printing number exceeds the upper limit number. 5. The image forming apparatus described. The determination means includes
Setting means for enabling the user to set the number of copies;
Reading means for reading image data of a document;
Dot counting means for counting the number of dots of image data read by the reading means;
The number of dots for calculating the number of dots of image data to be printed by calculating the product of the number of dots counted by the dot counting means and the number of copies set by the setting means A calculation means;
An upper limit dot number storage that stores an upper limit dot number that uses the total number of dots of an image formed on a sheet as an initial value when printing is performed using an amount of toner obtained by subtracting the first threshold value from the second threshold value. Means,
Until the remaining amount of toner reaches the first threshold value and then reaches the first threshold value, the number of dots calculated by the dot number calculation unit is subtracted from the upper limit dot number for each printing process, and the upper limit dot number is updated. An upper limit dot number updating means to perform,
Until the remaining amount of toner reaches the first threshold value until the first threshold value is reached, the upper limit dot number before the update process is updated by the upper limit dot number update unit and the dot number calculation unit. A comparison means for comparing the number of dots and determining whether or not the number of dots exceeds the upper limit number of dots,
3. The determination unit according to claim 2, wherein, when the comparison unit determines that the number of dots exceeds the upper limit number of dots, the determination unit determines that the remaining amount of toner reaches a first threshold during printing. 3. The image forming apparatus according to 3. When the remaining amount of toner is less than or equal to the first threshold by the first remaining toner amount detecting unit, the display unit performs normal mode printing based on the image data of the original one by one on the recording paper. Alternatively, a third message is displayed informing that the eco-mode printing is selectable,
The mode changing unit changes the print setting from the default eco mode printing to the single mode printing when the user selects single mode printing in response to the third message. The image forming apparatus according to any one of?

Images