JP2008020536A - Image forming apparatus and toner management method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a printing device and a calculating method whereby the number of possible prints can be calculated with higher precision when an amount of remaining toner is not higher than a fixed level. <P>SOLUTION: When a near-end detecting section 101 detects that toner is almost used up, a storage section 104 stores information about the mount time and date and near-end detection time and date in relation to the identification information of the toner cartridge. Using the stored information, a calculating section 102 calculates a printable period. Examples of the calculating methods include (1) a method for calculating a printable period from the number of sheets on which regular printing is possible with an amount of toner remaining after the near-end detection and the standard number of prints per day and (2) a method for calculating a printable period in relation to the amount of remaining toner, from the elapsed time relative to the amount of toner used for a certain fixed period of time. Print output is allowed only for a printable period calculated from the near-end detection time and date stored in the storage section 104. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus and a toner management method for clarifying a toner ordering time from the number of printed sheets and the amount of used toner, and in particular, normal printing is possible from the past number of printed sheets and the amount of used toner. The present invention relates to an image forming apparatus and a toner management method that enable efficient use of toner by calculating a period.

  An image forming apparatus such as a printer includes a print controller that performs image processing on a PDL (Page Description Language) format print job, and a print engine that prints image data processed by the printer controller onto printing paper as a printing medium. Then, the print engine conveys the printing paper stored in the paper storage with a conveyance roll, and draws the image data processed by the printer controller on the conveyed printing paper. In this drawing process, the toner filled in the toner cartridge is sprayed on the printing paper, and the toner sprayed by the pressure bonding device is colored on the printing paper.

  The number of sheets that can be printed by the print output performed by the print engine is determined by the number of print sheets stored in the sheet storage and the remaining amount of toner filled in the cartridge. The toner can be used without waste by replacing the toner when the toner is used up.

  However, if you try to use the toner until it runs out completely, “blurred printing” will begin to occur when the toner capacity falls below a certain remaining capacity, so the desired print result will not be obtained and you will have to reprint. Problems can occur. Since this results in wasted printing paper, it is generally not used until the toner is completely removed, but is generally replaced before faint printing occurs.

  At this time, there is a technique for notifying that it is time to replace the toner when the remaining toner amount reaches a predetermined amount, and it is possible to recognize that the remaining toner capacity has been reduced by using this technique. Thus, it is possible to avoid a failure in print output due to insufficient toner remaining capacity. The remaining capacity at this time is not usually a capacity that causes faint printing immediately, but is a capacity that can still be printed and output, so the user is in the toner replacement period. In many cases, even if it is notified, it is often used continuously, and as a result, faint printing may occur.

  As a background to this, since it is still possible to perform normal print output when it is notified that it is time to replace the toner, there is an intention to use the toner as much as possible.

  Patent Document 1 discloses a conventional technique in which a toner container replacement request message is displayed on a host-side screen at an optimal timing for each user, and a user can place an order for a new toner at an optimal timing. . In this technique, the average number of output sheets per day is calculated by dividing the total of the number of output sheets on the current day by the number of days in the past, and the number of print output sheets in the toner container in use is calculated. In addition, by calculating the average output number of toner containers that have been used in the past and displaying the number of days that printing can be performed with the currently used toner container, it is possible to prevent the situation where printing cannot be continued due to the absence of toner. Yes.

  In the prior art disclosed in Patent Document 2, a consumable counter is counted up during an image forming operation, and a report level is determined by determining whether the count value of the consumable count is equal to or greater than a preset report level value. If the value is greater than or equal to the value, it is notified to the central control device connected via the communication line so that the product can be delivered before the consumable item runs out.

In Patent Document 2, the notification level value is further subtracted from the count value of the consumable counter after the notification, and counting is started again.
JP 2004-69988 A JP-A-11-119606

  In the technologies disclosed in Patent Documents 1 and 2, whether print data can be printed is determined every time a print request is made, and if all the print data cannot be printed, printing is not performed. Show.

  This is because there is a case where print output is not performed in spite of a state where normal print output is possible, and there is a problem that toner is wasted if the toner is replaced in this state. .

  Therefore, an object of the present invention is to provide a printing apparatus and a calculation method that can calculate the number of printable sheets with higher accuracy when the toner is below a certain remaining capacity.

  In order to achieve the above object, a first aspect of the present invention provides a toner amount detecting means for detecting a remaining toner amount of toner filled in a toner cartridge, and a toner whose remaining toner amount detected by the toner amount detecting means is designated in advance. A near-end detection unit that detects a near-end state that is less than or equal to an amount; a calculation unit that calculates the number of sheets that can be printed normally by the amount of remaining toner at the time when the near-end state is detected by the near-end detection unit; and the calculation unit And print control means for controlling print output within the range of the number of printed sheets that can be printed normally.

  The invention of claim 2 further comprises management means for managing a standard printable number of prints with the total toner amount of the toner cartridge in the invention of claim 1, wherein the calculation means is controlled by the near-end detection means. The number of printed sheets printed up to the near-end state from the amount of toner used until the near-end state is detected and the amount of toner per unit number used to print out the standard number of prints managed by the management unit And calculating the number of prints that can be printed normally by subtracting the number of printed sheets from the standard number of prints managed by the management means.

  The invention of claim 3 further comprises counting means for counting the number of printed sheets in the invention of claim 1, wherein the calculating means uses the amount of toner used for the number of printed sheets counted by the counting means. And calculating the number of prints that can be normally printed with the remaining toner amount.

  According to a fourth aspect of the present invention, in the first to third aspects of the invention, the printing control unit increases or decreases the number of printed sheets calculated by the calculating unit based on printing conditions, and is within a range of the increased or decreased number of printed sheets. And printing out.

  According to a fifth aspect of the present invention, the remaining toner amount of the toner filled in the toner cartridge is detected by the toner amount detecting means, and the remaining toner amount detected by the toner amount detecting means is equal to or less than a predetermined toner amount. And detecting a state by a near-end detection unit, and calculating the number of prints that can be normally printed based on the amount of remaining toner at the time when the near-end state is detected by the near-end detection unit.

  According to the present invention, when the near end is detected, the printable period after the near end detection is calculated based on the remaining toner amount in the near end state, and the printable period is added to the date and time when the near end is detected. Since the timing is calculated and the reverse calculation is performed by subtracting the lead time required for toner arrangement, toner ordering can be performed at the optimum timing, and the convenience of toner ordering is improved. Play.

  Hereinafter, an embodiment of an image forming apparatus and a toner management method according to the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 is an apparatus configuration diagram configured by applying an image forming apparatus and a toner management method according to the present invention.

  In FIG. 1, a printer 100 includes a near-end detection unit 101, a calculation unit 102, a timing unit 103, a storage unit 104, an attachment / detachment detection unit 105, a display unit 106, a print control unit 107, a print engine 108, a toner cartridge mounting unit 109, a toner. The cartridge 110 is configured, and the toner ordering time is clarified by notifying the time when the toner filled in the toner cartridge 110 will run out. Further, the printer 100 has a function of detecting a near-end state indicating that the remaining amount of toner is equal to or less than a predetermined amount, and the detected near-end state is a state in which normal printing that does not cause fading printing is possible. This indicates that the printer is in a state in which faint printing will occur soon.

  The time when the toner runs out is a period during which normal printing can be performed with the remaining toner amount in the near-end state when the near-end indicating that the remaining amount of toner is equal to or less than a predetermined amount is detected (hereinafter, “printable period”). ) Is added, and the toner ordering time is clarified by subtracting the lead time required for toner preparation from this toner out-of-period.

  The configuration of the printer 100 that calculates the toner ordering time will be described below.

  In the printer 100, a print request from an external device such as a client PC connected via a communication line is received by the print control unit 107, converted into a PDL format, subjected to image processing, and then printed out from the print engine 108. At this time, the print control unit 107 issues a print instruction to the print engine 108 and, at the same time, adds the number of prints instructed to the print to the number of printed sheets stored in the storage unit 104 and prints after the toner cartridge 110 is mounted. Update the number of printed pages.

  The number of printed sheets stored in advance in the storage unit 104 is initialized when the toner cartridge 110 is mounted on the toner cartridge mounting unit 109, and the number of printed sheets printed on the toner filled in the toner cartridge 110 is printed. Is shown.

  When the toner cartridge 110 is attached to the toner cartridge attachment unit 109, the attachment / detachment detection unit 105 detects the attachment of the toner cartridge, acquires the attachment date and time from the time measuring unit 103, and stores it in the storage unit 104. The storage unit 104 manages the identification information for identifying the mounted toner cartridge 110 in association with the mounting date and time.

  When such print output is continuously performed for a certain period and the remaining toner amount becomes equal to or less than a certain capacity, the near-end detection unit 101 detects the near-end state, and the date and time information at the time of detection of the near-end state is obtained from the timing unit 103. Acquired and stored in the storage unit 104. That is, by detecting the near-end state, the storage unit 104 stores information on the mounting date and time and near-end detection date and time with respect to the identification information of the toner cartridge.

  A near-end detection method performed by the near-end detection unit 101 will be described with reference to FIG.

  FIG. 2 shows a state in which the toner cartridge 110 is filled with toner, and a light emitting element 201 and a light receiving element 202 are installed on both the left and right sides of the toner cartridge. The light emitting element 201 is an element that emits laser light, and the light receiving element 202 is an element that receives the laser light emitted from the light emitting element 201, and is provided at a position where the laser light having straightness can be received. Yes.

  When the laser light emitted from the light emitting element 201 is received by the light receiving element 202, it is detected that the obstacle (toner) has disappeared on the orbit of the laser light and the near end state is detected. At this time, the laser light emitted from the light emitting element 201 is emitted in parallel with the surface of the toner, and when the light receiving element 202 receives a certain amount of laser light, it is detected as near-end.

  In FIG. 2, FIG. 2A shows the state of the toner cartridge 110 filled with a sufficient amount of toner. In this case, the laser light emitted from the light emitting element 201 is blocked by the toner on the orbit. The laser beam cannot be received by the light receiving element 202. On the other hand, FIG. 2B shows a state of the toner cartridge 110 having a toner amount capable of receiving the laser light emitted from the light emitting element 201 by the light receiving element 202, and the laser light starts to be received by the light receiving element 202. The near end can be detected by receiving a certain amount of light by the light receiving element 202.

  Further, FIG. 2C shows a toner cartridge 110 having a toner amount in which a certain number of sheets are printed out even after it is detected as being in the near-end state, and it is not strange even if faint printing occurs.

  As described above, when the laser light emitted from the light emitting element 201 is received by the light receiving element 202 over a certain amount, it is detected that the near end state is reached.

  In addition to the method of detecting the near end using the light receiving element 201 and the light emitting element 202, a configuration in which the near end state is detected by measuring the amount of electric resistance generated based on the toner amount may be employed. .

  Near end can be detected by such a method.

  The near-end detection unit 101 that has detected the near-end state notifies the calculation unit 102 that the near-end state has been detected, and the calculation unit 102 calculates a printable period during which print output is possible after detecting the near-end state. The toner ordering time is calculated from the printable period and the near end detection date and time when the near end is detected.

  By displaying the toner ordering time calculated by the calculating unit 102 on the display unit 106, a toner ordering request is made to the user (printer administrator). At the time of this toner order request, the calculation unit 102 transfers the toner order timing calculated to an external device such as a client PC, and the client PC is configured to start an ordering application or an ordering Web screen. In addition, information such as order date / time and order source may be automatically input to order the toner.

  As a calculation method of the printable period by the calculation unit 102, (1) the number of prints (PV: PrintVolume) (hereinafter referred to as “PV number”) that can be normally printed with the remaining toner amount after near-end detection, and the number of unit days A method for calculating the printable period (E) from the standard number of prints, and (2) calculating the printable period (E) for the remaining toner amount at the near-end detection from the elapsed time for the toner usage amount for a certain period. There is a way to do it.

  First, (1) a method of calculating a printable period (E) from the number of PVs (F) that can be normally printed with the amount of residual toner after near-end detection and the standard number of prints (G) per unit day. explain.

  The standard number of printed sheets (G) per unit day shown in this method (1) is the number of printed sheets per day. For example, the number of printed sheets per day has elapsed from when the toner cartridge is installed until the near end is detected. It can be calculated by dividing the number of days by the number of printed pages.

  Further, the number of PV (F) that can be printed normally with the amount of residual toner after near-end detection can be calculated by the following three methods.

  As a first calculation method, a method for calculating the number of PV based on a printing ratio (hereinafter referred to as “print density”) with respect to the entire printed document will be described.

  In this method, first, the total toner amount mounted on the toner cartridge is set to “Y”, and the remaining toner amount at the near end detection is set to “x”. In this case, the remaining toner amount “x” is a predetermined ratio with respect to the total toner amount “Y”. For example, when the near end is 20% or less of the total toner amount “Y”, the near end detection time is The remaining toner amount “x” is obtained as “Y × 0.2”.

  In addition, the number of PVs guaranteed to be printed with respect to the residual toner amount “x” at the time of near-end detection depends on the paper size and the print density. This print density is the print density “ The printing ratio is calculated as “100%”. At this time, if the amount of toner used when printing at a printing density of “100%” is “y”, the amount of toner used when printing at a printing density of “k%” is obtained as “y × (k / 100)”. be able to. This used toner amount “y” is a toner amount consumed when printing is performed at a printing density “100%”, and is a value determined in advance for each paper size.

  Thus, the number of PVs (PV100) for which printing is guaranteed when printing is performed at a printing density of “100%” can be calculated by the following (Formula 1).

PV100 = x / y (Formula 1)
Further, the number of PVs (PV_k) for which printing is guaranteed when printing is performed at a printing density “k%” can be calculated by the following (Formula 2).

PV_k = x / (y * (k / 100)) (Formula 2)
Incidentally, the print density “0%” indicates a case where printing is performed in a blank state, but the print density “0%” is excluded because it is equivalent to not printing output. As a result, the print density is in the range of “0 <k <= 100”.

  From the above, the PV number after near-end detection is calculated by setting the optimum printing density “k” according to the printing environment.

  The print density “k” is relatively higher in an environment in which image data including a lot of photographs and pictures is frequently printed out than in an environment in which image data composed of character data is frequently printed out. This print density “k” can be calculated from a statistically calculated value or a past actual value in the same environment.

  Next, as a second calculation method, a method for calculating the number of PV when the number of printable sheets is designated in advance with respect to the total amount of unused toner will be described.

  In this method, first, the total toner amount packed in the toner cartridge is “Y”, the standard toner usage amount used when a standard image is printed on the printing paper is “A”, and this standard toner usage amount is When “A” is printed out for the total toner amount “Y”, the standard number of printed sheets is “n”. Also, the near-end toner usage rate with respect to the total toner amount “Y” is set to “a”, and when this toner usage rate “a” is reached, it is detected that the toner is near-end.

  The standard number of prints “n” at this time is the number of prints that can be printed when the standard toner usage amount “A” is printed. For example, a general toner cartridge can output about 5000 sheets. Therefore, a large-capacity toner cartridge can print out about 8000 sheets. As described above, the standard print number “n” is a predetermined value.

  Further, since the near end is detected based on the usage ratio “a” of the toner used with respect to the total toner amount “Y”, for example, when the toner is used at 80% with respect to the total toner amount “Y”, In this case, the toner usage rate “a” is indicated as “0.8”.

  Then, the number of printed sheets (Pout) at the time when the near-end toner usage ratio “a” is reached can be calculated by the following (Equation 3).

Pout = (Y × a) / A (Formula 3)
This (Expression 3) is an expression showing the number of printed sheets (Pout) printed out by printing the toner capacity (Y × a) used at the near end time with the standard toner usage amount “A”, The number of printed sheets that have already been printed is calculated.

  Therefore, the number of PV (PV) for which printing is guaranteed based on the toner usage ratio “a” at the near end time can be calculated by the following (formula 4).

PV = n−Pout = n − ((Y × a) / A) (Formula 4)
The toner usage ratio “a” also falls within the range of “0 <a <= 1”.

  By using such a calculation method, it is possible to calculate the remaining number of PV when the standard toner usage amount “A” is printed out from the standard number of printed sheets.

  Incidentally, the standard toner usage amount “A” may be calculated from the total toner amount “Y” required for printing out the standard printing number “n”. In this case, the standard toner usage amount “A” "Can be obtained as" A = Y / n ".

  By applying this formula to (Formula 4), the PV number can be calculated by (Formula 5) shown below.

PV = n × (1−a) (Formula 5)
This is the number of sheets that can be printed only for the ratio of the remaining toner amount to the total toner amount in the standard print number.

  As a third calculation method, a method of calculating the number of PV by estimating the number of printed sheets from the number of printed sheets with respect to the amount of used toner will be shown.

  In this method, first, the total toner amount packed in the toner cartridge is set to “Y”, the number of printed sheets counted by a counter or the like is set to “PV0”, and the toner that is near-end with respect to the total toner amount “Y” is set. The usage rate is “a”.

  In this case, the toner amount “b” used to print out the printed number “PV0” that has already been printed out can be calculated by the following (formula 6).

b = PV0 / (Y × a) (Formula 6)
Therefore, the number of printable sheets (PV) after near-end detection can be calculated by the following (Formula 7).

PV = b * Y (1-a) = (PV0 / (Y * a)) * Y (1-a) (Formula 7)
By using such a calculation method, the remaining number of printable sheets can be calculated based on the state of the past print history for each use environment.

  You may multiply the arithmetic expression (Formula 4) and (Formula 7) which calculate the number of PV by the said 2nd method and the 3rd method by safety factor "s" (0 <s <1). This safety factor “s” makes it possible to calculate the optimum number of PV (F) in accordance with the use environment.

  The printable period (E) can be calculated by the following (Equation 8) obtained by dividing the PV number (F) calculated by the above method by the standard number of printed sheets (G) per unit day.

Printable period (E) = Number of PV (F) / Number of printed sheets (G) (Equation 8)
Next, (2) a method of calculating the printable period (E) for the remaining toner amount at the near-end detection from the elapsed time for the toner usage amount for a certain period will be described.

  In this method (2), when calculating the printable period, the toner cartridge attachment date / time information (A) stored in the storage unit 104 and the near-end detection date / time (B) when the near-end is detected are acquired. Further, the total toner amount (C) in a state where the toner cartridge pre-stored in the storage unit 104 is fully filled and the remaining toner amount (D) at the near-end detection time are acquired.

  The following (Equation 9) holds based on the acquired information.

Printable period (E) = (D / (C−D)) × (B−A) (Equation 9)
That is, since (Equation 9) uses the used toner amount (CD) in the print use period (BA), the remaining toner amount (D) can be printed out in the printable period (E). It shows that there is.

  As described above, using the printable period calculated in (Expression 8) and (Expression 9), the period (H) during which the toner runs out can be calculated according to (Expression 10) below.

Toner running out period (H) = near end detection date and time (B) + printable period (E) (Equation 10)
The toner ordering time can be calculated by subtracting the lead time required for toner preparation from the period (H) during which the toner runs out calculated by (Equation 10).

  By displaying the information on the toner ordering time calculated in this way on the display unit 106, the user (administrator) can perform the toner ordering process at an appropriate time.

  Next, the flow of processing in the apparatus configuration shown in FIG. 1 is shown in the flowcharts of FIGS.

  FIG. 3 is a flowchart showing a flow of processing performed by replacing the toner cartridge.

  In FIG. 3, the process is started when the toner cartridge is removed from the toner cartridge mounting portion in order to replace it due to the toner cartridge running out, and a new toner cartridge full of new toner is installed. The

  When the toner cartridge is attached, it is detected that the toner cartridge is attached (301), and attachment date and time information (A) such as the detected current time and date is acquired (302). In addition to this, an identification number such as a physical address assigned to the toner cartridge is also read.

  The acquired toner cartridge installation date / time information and identification number are stored (303).

  Thus, the time when the toner cartridge is replaced is stored, and the ordering time of the toner for the next replacement can be clarified.

  FIG. 4 is a flowchart showing the flow of processing when print output is performed with a sufficient amount of toner filled in the toner cartridge.

  In FIG. 4, when a print request is received from an external device such as a client PC connected to the printer, the process is started, a print output process is performed in response to the print request (401), and the number of printed sheets printed by the print output process ( (Number of terms) is calculated (402).

  The number of printed sheets at this time is the number of sheets for single-sided printing. When double-sided printing is performed, the number of printed sheets is calculated as a double of single-sided printing. Of course, it may be calculated using another method for calculating the number of printed sheets.

  Then, the number of printed output sheets is added to the number of already printed sheets and stored (403).

  Note that the number of prints printed out by the print output process is the number of prints for which a print instruction has been issued to the print engine. Of course, the number of sheets printed normally by the print output by the print engine is not limited to this. You may comprise so that it may count.

  By such processing, the number of printed pages can be managed.

  FIG. 5 is a flowchart showing the flow of the toner ordering process of the present invention.

  In FIG. 5, when the near-end state where the print output is continuously performed and the toner amount becomes equal to or smaller than the predetermined amount is detected (501), the time when the near-end state is detected and the date / time of detection (B) are acquired (502). ). The acquired detection date and time is stored (503), and then a process for calculating a printable period is performed (504).

  The detailed processing flow in this printable period calculation method is shown in FIGS.

  From the calculated printable period and the acquired date and time information when the near-end state is detected, the time when the toner runs out is calculated (505), and the time when the toner runs out is displayed (506). Further, a web page for arranging toner is displayed (507), and when a user (administrator) inputs predetermined information or is automatically input, toner is arranged (508).

  As a result, toner can be arranged at an optimal timing before the toner runs out.

  FIG. 6 shows a detailed flow in the printable period calculation process shown in FIG.

  In FIG. 6, when the near-end state is detected, the number of PVs (F) that can be normally printed is calculated based on the remaining toner amount after the near-end detection (601), and then the standard number of prints per unit day ( G) is calculated (602). The printable period (E) is calculated by dividing the calculated number of PV (F) by the standard number of printed sheets (G) (603).

  FIG. 7 shows a detailed flow of another example in the calculation process of the printable period.

  In FIG. 7, when the near end state is detected, the total toner amount (C) filled in the toner cartridge is acquired (701), and the remaining toner amount (D) when the near end state is detected is acquired. (702).

  The acquired total toner amount (C) and residual toner amount (D), date and time information (A) when the toner cartridge shown in the flowchart of FIG. 3 is attached, and detection date and time when the near-end state shown in the flowchart of FIG. 5 is detected From (B), a printable period (E) is calculated (703).

  As described above, the printable period (E) can be calculated by the processes shown in FIGS.

  With the above processing, the image forming apparatus of the present invention can perform toner ordering processing at an optimal timing before the toner runs out.

  As a result, it is possible to prevent print output from being stopped due to toner being completely exhausted.

  The present invention is not limited to the embodiments described above and shown in the drawings, and can be implemented with appropriate modifications within the scope not changing the gist thereof.

  The present invention is useful for ordering toner at an optimal timing with respect to the remaining amount of toner.

1 is a configuration diagram of an apparatus configured by applying an image forming apparatus and a toner management method according to the present invention. FIG. 5 is a diagram illustrating a state where toner is filled in a toner cartridge. 5 is a flowchart showing a flow of processing performed by replacement of a toner cartridge. 6 is a flowchart illustrating a processing flow when print output is performed with a sufficient amount of toner charged in a toner cartridge. 6 is a flowchart showing a flow of toner ordering processing according to the present invention. 6 is a detailed flowchart of the printable period calculation process illustrated in FIG. 5. 12 is a detailed flowchart of another example in the printable period calculation process.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Printer 101 Near end detection part 102 Calculation part 103 Timing part 104 Storage part 105 Attachment / detachment detection part 106 Display part 107 Print control part 108 Print engine 109 Toner cartridge mounting part 110 Toner cartridge

Claims (5)

A toner amount detecting means for detecting a remaining toner amount of toner filled in the toner cartridge;
A near-end detection unit that detects a near-end state in which a residual toner amount detected by the toner amount detection unit is equal to or less than a predetermined toner amount;
Calculation means for calculating the number of prints that can be normally printed by the amount of residual toner at the time when the near-end state is detected by the near-end detection means;
A printing apparatus comprising: a printing control unit that controls printing output within a range of the number of printed sheets that can be printed normally by the calculation unit. Management means for managing a standard printable number of prints based on the total amount of toner in the toner cartridge;
The calculating means includes
Printing from the amount of toner used until the near-end state is detected by the near-end detection unit and the amount of toner per unit number used to print out the standard number of prints managed by the management unit to the near-end state The printing apparatus according to claim 1, further comprising: calculating an output number of printed pages, and calculating a number obtained by subtracting the printed number from the standard print number managed by the management unit as a print number that can be printed normally. A counting means for counting the number of printed sheets;
The calculating means includes
The printing apparatus according to claim 1, further comprising: calculating a number of prints that can be normally printed with the remaining toner amount based on a ratio of a used toner amount to a printed number of sheets counted by the counting unit. The print control means includes
The printing apparatus according to claim 1, further comprising: increasing / decreasing the number of printed sheets calculated by the calculating unit based on a printing condition, and performing printing output within a range of the increased / decreased number of printed sheets. A toner amount detecting means detects the amount of toner remaining in the toner cartridge;
A near-end detection unit that detects a near-end state in which a residual toner amount detected by the toner amount detection unit is equal to or less than a predetermined toner amount;
A calculation method including calculating the number of prints that can be normally printed based on the remaining toner amount at the time when the near-end state is detected by the near-end detection unit.

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