Patent Publication Number: US-10331060-B2

Title: Image forming apparatus capable of preventing unnecessary replacement of toner cartridge, method of controlling the same, and storage medium

Description:
BACKGROUND OF THE INVENTION 
     Field of the Invention 
     The present invention relates to an image forming apparatus, a method of controlling the same, and a storage medium, and more particularly to an image forming apparatus that includes a plurality of consumable parts, a method of controlling the same, and a storage medium. 
     Description of the Related Art 
     There has been known an MFP as an image forming apparatus that includes a plurality of consumable parts, such as a photosensitive drum, a developing device, and toner cartridges. For the MFP, each consumable part is configured to be removably mounted, and a user can replace each consumable part separately (see e.g. Japanese Laid-Open Patent Publication (Kokai) No. 2013-97069). In the MFP constructed as above, the remaining lifetime of each consumable part is notified based on the amount of usage of the consumable part (see e.g. Japanese Laid-Open Patent Publication (Kokai) No. H10-52964). This makes it possible for the user to be easily aware of a time for replacing the consumable part. 
     Incidentally, in the MFP, in a case where the photosensitive drum or the developing device (hereinafter referred to as the “drum part”) is replaced by a new drum part and then a first time operation of the new drum part is performed, toner supplied from the toner cartridge is used as lubricant for the first time operation. In the MFP, it is preferable that the toner cartridge as well is simultaneously replaced when the drum part is replaced, in order to prevent the lubricant for the first time operation from becoming insufficient. 
     However, if the user is compelled to replace the toner cartridge as well in all cases of replacing the drum part, there can be a case where even though the toner cartridge has a sufficient amount of toner remaining therein, it is replaced by the user. That is, the conventional MFP has a problem that a toner cartridge which is not required to be replaced is sometimes replaced when a drum part is replaced. 
     SUMMARY OF THE INVENTION 
     The present invention provides an image forming apparatus that is capable of preventing unnecessary replacement of a toner cartridge when a drum part is replaced, a method of controlling the same, and a storage medium. 
     In a first aspect of the invention, there is provided an image forming apparatus on which a toner member for supplying toner, and another member that uses the toner supplied from the toner member as lubricant when the other member performs a first time operation after being mounted, are removably mounted, comprising an acquisition unit configured to acquire a value indicative of a remaining amount of toner stored in the toner member and a value indicative of a remaining lifetime of the other member, and a notification unit configured to provide a notification relevant to replacement of the other member when the value indicative of the remaining lifetime of the other member is not larger than a predetermined threshold value, wherein the notification unit switches contents of the notification according to the value indicative of the remaining amount of toner stored in the toner member. 
     In a second aspect of the invention, there is provided a method of controlling an image forming apparatus on which a toner member for supplying toner, and another member that uses the toner supplied from the toner member as lubricant when the other member performs a first time operation after being mounted, are removably mounted, comprising acquiring a value indicative of a remaining amount of toner stored in the toner member and a value indicative of a remaining lifetime of the other member, and providing a notification relevant to replacement of the other member when the value indicative of the remaining lifetime of the other member is not larger than a predetermined threshold value, wherein said providing the notification includes switching contents of the notification according to the value indicative of the remaining amount of toner stored in the toner member. 
     In a third aspect of the invention, there is provided a non-transitory computer-readable storage medium storing a computer-executable program for executing a method of controlling an image forming apparatus on which a toner member for supplying toner, and another member that uses the toner supplied from the toner member as lubricant when the other member performs a first time operation after being mounted, are removably mounted, wherein the method comprises acquiring a value indicative of a remaining amount of toner stored in the toner member and a value indicative of a remaining lifetime of the other member, and providing a notification relevant to replacement of the other member when the value indicative of the remaining lifetime of the other member is not larger than a predetermined threshold value, wherein said providing the notification includes switching contents of the notification according to the value indicative of the remaining amount of toner stored in the toner member. 
     According to the present invention, it is possible to prevent unnecessary replacement of a toner member (toner cartridge) when a drum part is replaced. 
     Further features of the present invention will become apparent from the following description of exemplary embodiments (with reference to the attached drawings). 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic block diagram of an MFP as an image forming apparatus according to an embodiment of the present invention. 
         FIG. 2  is a schematic cross-sectional view of a printer engine appearing in  FIG. 1 . 
         FIG. 3  is a flowchart of a display control process performed by the MFP shown in  FIG. 1 . 
         FIGS. 4A to 4D  are views of examples of messages displayed on a console section appearing in  FIG. 1 . 
         FIG. 5  is a flowchart of a variation of the display control process shown in  FIG. 3 , which is performed by a variation of the present embodiment. 
         FIG. 6  is a flowchart of a flag control process performed by the variation of the present embodiment. 
         FIG. 7  is a view of contents of notifications given according to remaining lifetime values of a toner part appearing in  FIG. 2 . 
     
    
    
     DESCRIPTION OF THE EMBODIMENTS 
     The present invention will now be described in detail below with reference to the accompanying drawings showing embodiments thereof. 
       FIG. 1  is a schematic block diagram of an MFP (Multi-Function Peripheral)  100  as an image forming apparatus according to an embodiment of the present invention. 
     Referring to  FIG. 1 , the MFP  100  includes a controller unit  101 , a console section  116 , a sheet feeder  117 , and a printer engine  118 . The controller unit  101  is connected to the console section  116  and the printer engine  118 , and the sheet feeder  117  is connected to the printer engine  118 . The controller unit  101  is comprised of a CPU  102 , a ROM  103 , a RAM  104 , an NVMEM  105 , a USB interface  106 , an image bus interface  107 , a console section interface  108 , a LAN interface  109 , a wireless LAN interface  110 , and a RTC (Real Time Clock)  111 . Further, the controller unit  101  includes a RIP  113 , a printer interface  114 , and an image processor  115 . The CPU  102 , the ROM  103 , the RAM  104 , the NVMEM  105 , the USB interface  106 , the image bus interface  107 , the console section interface  108 , the LAN interface  109 , the wireless LAN interface  110 , and the RTC  111  are connected to each other via a system bus  119 . The image bus interface  107 , the RIP  113 , the printer interface  114 , and the image processor  115  are connected to each other via an image bus  112 . 
     The controller unit  101  controls the overall operation of the MFP  100 . The CPU  102  executes programs stored in the ROM  103  and the like to thereby perform various kinds of processing. The ROM  103  is a rewritable nonvolatile memory, and stores the programs and the like executed by the CPU  102 . The RAM  104  is used as a work area for the CPU  102 . Further, the RAM  104  is used as an area for temporarily storing various data. The NVMEM (Non-Volatile Memory)  105  stores setting information and the like. The USB interface  106  performs data communication with USB devices, such as USB memories, connected to USB terminals (not shown) of the MFP  100 . 
     The image bus interface  107  is a bus bridge that connects between the system bus  119  and the image bus  112 , and converts data structure. The console section interface  108  performs data communication with the console section  116 . For example, the console section interface  108  acquires information input by a user&#39;s operation on the console section  116 , from the console section  116 . Further, the console section interface  108  receives from the CPU  102  a display control signal for performing display control of the console section  116 , and delivers the display control signal to the console section  116 . With this, screens for configuring various settings of the MFP  100 , messages and the like are displayed on the console section  116 . The LAN interface  109  performs wired LAN communication with external apparatuses connected thereto via a LAN cable, not shown. The wireless LAN interface  110  performs wireless communication with external apparatuses which can perform wireless LAN communication. The RTC  111  is a real time clock that functions as a clock for the MFP  100 . The RTC  111  includes a battery, not shown, and continues its operation even when the MFP  100  is in a power-off state. 
     The image bus  112  is formed by a PCI bus or an IEEE 1394, and transfers image data at a high speed. The RIP (Raster Image Processor)  113  rasterizes vector data, such as a PDL code, into a bitmap image. The printer interface  114  performs data communication with the printer engine  118 , and performs checking of a state thereof, and synchronous-to-asynchronous or asynchronous-to-synchronous conversion of image data. For example, the printer interface  114  transmits image data to the printer engine  118 . Further, the printer interface  114  acquires respective remaining lifetime values of a drum part  201  and a toner part  202 , described hereinafter with reference to  FIG. 2 , and outputs the acquired remaining lifetime values to the CPU  102 . The image processor  115  corrects, manipulates, and edits received image data. Further, the image processor  115  performs resolution conversion and the like on image data to be output. 
     The console section  116  includes a plurality of keys, not shown, and a display section, not shown, for operating the MFP  100 . For example, the console section  116  displays messages  401  to  404 , described hereinafter with reference to  FIGS. 4A to 4D . The sheet feeder  117  stores recording sheets, and feeds them to the printer engine  118  for performing printing. The printer engine  118  performs printing on the recording sheets based on image data acquired from the printer interface  114 . 
       FIG. 2  is a schematic cross-sectional view of the printer engine  118  appearing in  FIG. 1 . 
     Referring to  FIG. 2 , the printer engine  118  includes the drum part  201 , the toner part  202  (toner member, i.e. toner cartridge), a solid-state laser device  203 , a rotary polygon mirror  204 , a transfer device  207 , a fixing device  208 , and a cleaner  209 . The drum part  201  is comprised of a photosensitive drum  205  and a developing device  206 . 
     The drum part  201 , which is an integral-type consumable part including the photosensitive drum  205  and the developing device  206 , is configured to be removably mounted, and the replacement thereof can be performed by the user. The MFP  100  calculates the remaining lifetime of the drum part  201  based on the number of rotations of the photosensitive drum  205 . Whenever the photosensitive drum  205  rotates a predetermined number of times, a value indicative of the remaining lifetime (hereinafter referred to as the “remaining lifetime value”) of the drum part  201  is reduced from 100% by a unit of 1%. In the MFP  100 , when a first time operation of a new drum part  201  is performed after mounting the same, toner supplied from the toner part  202  is used as lubricant for the operation of internal components of the new drum part  201 . 
     The toner part  202 , which is a consumable part that supplies toner to the drum part  201 , is configured to be removably mounted, and the replacement thereof can be performed by the user. The MFP  100  calculates a value indicative of the remaining amount of toner in the toner part  202  (hereinafter referred to as the “remaining lifetime value of the toner part  202 ”). In the present embodiment, a description will be given of an example in which the remaining lifetime value of the toner part  202  is expressed in three stages, i.e. a stage in which the remaining lifetime value is not larger than 10% (third stage), a stage in which the remaining lifetime value is larger than 10% and also not larger than 20% (second stage), and a stage in which the remaining lifetime value is 21% to 100% (first stage). The values of the respective stages are given only by way of example. Further, the remaining lifetime value of the toner part  202  may be managed by using a number of stages larger than the three stages. It is only required that the user can distinguish at least between a stage in which replacement of the toner part is required (the third stage), a stage in which preparation for replacement of the toner part is required since the time for the replacement is approaching (the second stage), and a state in which a sufficient amount of toner remains (the first stage). 
     The solid-state laser device  203  includes a light emitting element, not shown, and irradiates light onto the rotary polygon mirror  204 . The rotary polygon mirror  204  rotates at a high speed, and scans the light irradiated from the solid-state laser device  203 , to thereby irradiate the light onto a surface of the photosensitive drum  205 . The surface of the photosensitive drum  205  is charged to a predetermined potential, and an electrostatic latent image is formed on the surface of the photosensitive drum  205  based on the light irradiated by the rotary polygon mirror  204 . The developing device  206  accommodates two-component developer composed of toner particles and carrier particles, and develops the electrostatic latent image formed on the surface of the photosensitive drum  205  using the two-component developer. The toner particles and the carrier particles are supplied from the toner part  202  to the developing device  206 . The transfer device  207  electrostatically transfers a toner image formed on the photosensitive drum  205  to a recording sheet conveyed from the sheet feeder  117 . The recording sheet having the toner image electrostatically transferred thereon is conveyed to the fixing device  208 , and the fixing device  208  thermally fixes the toner image on the recording sheet. After the toner image has been transferred to the recording sheet, the cleaner  209  cleans toner remaining on the photosensitive drum  205 . 
     In the MFP  100 , before the drum part  201  and the toner part  202  reach their lifetime limits, more specifically, in the case where the respective remaining lifetime values of the drum part  201  and the toner part  202  are not larger than 10%, a notification for prompting replacement of the drum part  201  and the toner part  202  with new ones is provided. In a case where the MFP  100  provides a notification relevant to replacement of the drum part  201  which uses toner supplied from the toner part  202  as lubricant when performing a first time operation after replacement, the notification is provided so as to prompt replacement of both the drum part  201  and the toner part  202  (simultaneous replacement) so as to prevent the lubricant from becoming insufficient. However, assuming that the user is compelled to replace the drum part  201  and the toner part  202  at the same time in all cases of replacing the drum part  201 , even the toner part  202  which has a sufficient amount of toner remaining therein is replaced by the user. That is, this causes a problem that the toner part  202  which is not required to be replaced is replaced when the drum part  201  is replaced. 
     To overcome this problem, in the present embodiment, in the case where the MFP  100  provides the notification relevant to replacement of the drum part  201  when the remaining lifetime value of the drum part  201  is not larger than 10% (not larger than a predetermined threshold value), the MFP  100  switches contents of the notification according to the remaining lifetime value of the toner part  202 . The predetermined threshold value of the drum part  201  is set to 10%, by way of example, and may be set to any other suitable value. Further, the predetermined threshold value may not necessarily be a value represented by a ratio. For example, it may be determined whether or not the remaining lifetime value is not larger than the predetermined threshold value, by using the number of rotations of the drum, the number of printed sheets, or the like. 
       FIG. 3  is a flowchart of a display control process performed by the MFP  100  shown in  FIG. 1 . Hereinafter, with reference to  FIG. 3 , a description will be given of the display control process in which when the time for replacing the drum part  201  is approaching, contents of the notification to be displayed on the console section  116  are made different according to the remaining amount of toner in the toner part  202  (the remaining lifetime of the toner part  202 ). 
     As described above, when the drum part  201  is replaced with a new drum part  201 , toner as lubricant is required. Here, assuming that only the drum part  201  is replaced in a state in which the remaining amount of toner in the toner part  202  is small (e.g. not larger than 10%), the toner used as lubricant may become insufficient, or even if the toner may be sufficient for the first time operation of the drum part, the toner part  202  reaches its lifetime limit soon. To solve this problem, when the expiration of the lifetime of the drum part  201  is approaching, the remaining lifetime of the toner part  202  as well is checked. Then, in a case where the expiration of the remaining lifetime of the toner part  202  is also approaching, the user is prompted to replace both the drum part  201  and the toner part  202  with new ones. 
     On the other hand, when the expiration of the lifetime of the drum part  201  is approaching in a case where a value indicative of the remaining amount of toner stored in the toner part  202  is not smaller than the threshold value, a message indicating the time for replacing the toner part  202  is approaching is displayed. 
     The display control process in  FIG. 3  is performed by the CPU  102  executing an associated program stored in the ROM  103  or the like. The display control process in  FIG. 3  is executed in a case where the CPU  102  acquires the remaining lifetime value of the drum part  201 , which is not larger than 10%, from the printer interface  114 . 
     Referring to  FIG. 3 , first, the CPU  102  acquires the remaining lifetime value of the toner part  202  from the printer interface  114 , and determines whether or not the acquired remaining lifetime value of the toner part  202  is not larger than 10% (step S 301 ). 
     If it is determined in the step S 301  that the remaining lifetime value of the toner part  202  is not larger than 10%, the CPU  102  displays on the console section  116  the message  401  shown in  FIG. 4A , which prompts replacement of both the drum part  201  and the toner part  202  (step S 302 ). Note that in the present embodiment, in addition to the message  401 , the message  404  shown in  FIG. 4D , which suggests the necessity of replacement of the toner part  202 , may be displayed. After executing the step S 302 , the CPU  102  terminates the present process. 
     If it is determined in the step S 301  that the remaining lifetime value of the toner part  202  is larger than 10%, the CPU  102  determines whether or not the remaining lifetime value of the toner part  202  is not larger than 20% (step S 303 ). 
     If it is determined in the step S 303  that the remaining lifetime value of the toner part  202  is not larger than 20%, the CPU  102  alternately displays the message  402  shown in  FIG. 4B  and the message  403  shown in  FIG. 4C  at predetermined time intervals on the console section  116  (step S 304 ). The message  402  indicates that the time for replacing the drum part  201  is approaching, and the message  403  indicates that the time for replacing the toner part  202  is approaching. After executing the step S 304 , the CPU  102  terminates the present process. 
     If it is determined in the step S 303  that the remaining lifetime value of the toner part  202  is larger than 20%, the CPU  102  displays the message  402  on the console section  116  (step S 305 ), followed by terminating the present process. 
     According to the display control process described above with reference to  FIG. 3 , when the MFP  100  provides a notification relevant to replacement of the drum part  201  of which the remaining lifetime value is not larger than 10% (not larger than the predetermined threshold value), the MFP  100  switches contents of the notification according to the remaining lifetime value of the toner part  202 . That is, the notification relevant to replacement of the drum part  201  is not provided by the message  401  alone which prompts simultaneous replacement of the drum part  201  and the toner part  202 . Therefore, it is possible to prevent the user from being excessively prompted to replace both the drum part  201  and the toner part  202  when the drum part  201  is replaced, and hence it is possible to prevent unnecessary replacement of the toner part  202  when the drum part  201  is replaced. 
     Further, in the display control process described above with reference to  FIG. 3 , in a case where the remaining lifetime value of the drum part  201  is not larger than 10%, and also the remaining lifetime value of the toner part  202  is larger than 10% and also not larger than 20%, the messages  402  and  403  are alternately displayed at the predetermined time intervals on the console section  116 . Here, in the case where the remaining lifetime value of the toner part  202  is larger than 10% and also not larger than 20%, it is expected that soon afterwards the remaining lifetime value of the toner part  202  becomes not larger than 10%. From a viewpoint of efficient replacement of components, it is preferable that the drum part  201  and the toner part  202  are simultaneously replaced after the remaining lifetime value of the toner part  202  has become not larger than 10%. For this reason, before the remaining lifetime value of the toner part  202  becomes not larger than 10%, it is preferable to provide such a notification as will indicate that the time for replacing the drum part  201  and the toner part  202  is approaching, instead of prompting replacement of the drum part  201  and the toner part  202 . In view of this, in the present embodiment, in the case where the remaining lifetime value of the drum part  201  is not larger than 10%, and also the remaining lifetime value of the toner part  202  is larger than 10% and also not larger than 20%, the messages  402  and  403  are alternately displayed at the predetermined time intervals on the console section  116 . This makes it possible to positively notify the user that the time for replacing the drum part  201  and the toner part  202  is approaching although there is no need to replace them at once. 
     Furthermore, in the display control process described above with reference to  FIG. 3 , in a case where the remaining lifetime value of the drum part  201  is not larger than 10%, and also the remaining lifetime value of the toner part  202  is larger than 20%, only the message  402  is displayed on the console section  116 . That is, in this case, the message  403  is not displayed on the console section  116 . Here, in the case where the remaining lifetime value of the toner part  202  is larger than 20%, it is supposed that a necessary and sufficient amount of toner as lubricant for a first time operation of a new drum part  201  remains in the toner part  202 . In this case, there is no need to replace the toner part  202  at once, and therefore a notification for replacement of the toner part  202 , for example, the message  403  is not required to be displayed on the console section  116 . In view of this, in the present embodiment, in the case where the remaining lifetime value of the drum part  201  is not larger than 10%, and also the remaining lifetime value of the toner part  202  is larger than 20%, the message  403  is not displayed on the console section  116 . This makes it possible to avoid confusion of the user caused by an unnecessary notification relevant to replacement of the toner part  202 . 
     In the display control process described above with reference to  FIG. 3 , in a case where the remaining lifetime value of the drum part  201  and that of the toner part  202  are both not larger than 10%, the message  401  for prompting simultaneous replacement of the drum part  201  and the toner part  202  is displayed on the console section  116 . With this, in timing at which the drum part  201  and the toner part  202  are required to be replaced at the same time, it is possible provide a notification thereof by a message with appropriate contents. 
     Further, in the display control process described above with reference to  FIG. 3 , the drum part  201  is an integral-type member including the photosensitive drum  205  and the developing device  206 . Therefore, for replacement of the drum part  201  that uses toner supplied from the toner part  202  as lubricant for a first time operation thereof after replacement, it is possible provide a notification by a message with appropriate contents. 
     Although the description has been given of the present invention based on the above-described embodiment, the present invention is not limited to the above-described embodiment. For example, in the case where the remaining lifetime value of the drum part  201  is not larger than 10%, and also the remaining lifetime value of the toner part  202  is larger than 20%, a message prompting replacement of only the drum part  201  may be displayed on the console section  116 . This makes it possible to prompt the user to replace only the drum part  201  required to be replaced, out of the drum part  201  and the toner part  202 . 
     Further, in the above-described embodiment, the message  401  may be displayed on the console section  116  during a time period after both the remaining lifetime value of the drum part  201  and that of the toner part  202  were detected to be not larger than 10% and before the remaining lifetime value of the drum part  201  is detected to be larger than 20%. 
     Here, a case is assumed where when the message  401  is displayed on the console section  116 , the user forgets to replace one of the drum part  201  and the toner part  202 . For example, in a case where the user forgets to replace the toner part  202 , a tone replacement display control process, not shown, which is performed independently of the display control process in  FIG. 3 , causes the message  404 , shown in  FIG. 4D , which suggests the necessity of replacement of the toner part  202 , to be displayed on the console section  116 . Therefore, when the drum part  201  and the toner part  202  are to be replaced at the same time, even in a case where the user forgets to replace the toner part  202 , the user can be aware, before the toner part  202  reaches its lifetime limit, that it is required to replace the toner part  202  as well. On the other hand, in a case where the user forgets to replace the drum part  201 , the step S 305  is executed, whereby the message  402  shown in  FIG. 4B  is displayed on the console section  116 . In this case, the drum part  201  reaches its lifetime limit before the remaining lifetime value of the toner part  202  is reduced from 100% to 10% or smaller to cause the message  401  to be displayed on the console section  116 . For this reason, when the drum part  201  and the toner part  202  are to be replaced at the same time, if the user forgets to replace the drum part  201 , the user cannot be aware that it is required to replace the drum part  201  as well, before the drum part  201  reaches its lifetime limit. 
     In view of the above inconvenience, in a variation of the present embodiment, the message  401  is displayed on the console section  116  during a time period after both the remaining lifetime value of the drum part  201  and that of the toner part  202  were detected to be not larger than 10% and before the remaining lifetime value of the drum part  201  is detected to be larger than 10%. 
       FIG. 5  is a flowchart of a variation of the display control process shown in  FIG. 3 . In the example illustrated in  FIG. 3 , in a case where the remaining lifetime value of the drum part  201  is not larger than 10%, and also the remaining lifetime value of the toner part  202  is not larger than 10%, the message  401  prompting the user to replace both the drum part  201  and the toner part  202  is displayed. However, assuming that the user replaces only the toner part  202  without replacing the drum part  201 , according to the display control process shown in  FIG. 3 , there are performed the following operations: Since the remaining lifetime value of the drum part  201  is not larger than 10%, and also the remaining lifetime value of the toner part  202  has become not smaller than 20%, the process proceeds to the step S 305 , wherein the message  402  is notified which indicates that the time for replacing the drum part  201  is approaching. However, in the above-described example, as a matter of fact, the remaining lifetime value of the drum part  201  is smaller than 10%, and originally, a message prompting replacement of the drum part  201  should be displayed. To this end, by executing the variation of the display control process in  FIG. 5  and a flag control process in  FIG. 6 , the message  401  for prompting the user to replace both the drum part  201  and the toner part  202  is displayed, and thereafter the message  401  continues to be displayed until the drum part  201  is replaced, irrespective of the remaining lifetime value of the toner part  202 . This message  401  is displayed for prompting the user to replace the drum part  201 . As described above, it is possible to prompt the user to replace the drum part  201 . 
     The display control process in  FIG. 5  is performed by the CPU  102  executing an associated program stored in the ROM  303  or the like. The display control process in  FIG. 5  is performed in a case where the CPU  102  has acquired from the printer interface  114  the remaining lifetime value of the drum part  201 , which indicates that it is not larger than 10%. 
     Referring to  FIG. 5 , first, the CPU  102  determines whether or not a replacement display flag stored in the NVMEM  105  is on (step S 501 ). The replacement display flag is set to either on or off. Normally, the replacement display flag is set to off, whereas in a case where both the remaining lifetime value of the drum part  201  and that of the toner part  202  are not larger than 10%, the replacement display flag is set to on. 
     If it is determined in the step S 501  that the replacement display flag is not on, the CPU  102  executes the step S 301 . 
     If it is determined in the step S 301  that the remaining lifetime value of the toner part  202  is not larger than 10%, the CPU  102  executes the step S 302 , and then sets the replacement display flag to on (step S 502 ), followed by terminating the present process. On the other hand, if it is determined in the step S 301  that the remaining lifetime value of the toner part  202  is larger than 10%, the CPU  102  executes the step S 303  et seq. 
     If it is determined in the step S 501  that the replacement display flag is on, the CPU  102  displays the message  401  on the console section  116  (step S 503 ), followed by terminating the present process. 
       FIG. 6  is a flowchart of the flag control process performed by the MFP  100  shown in  FIG. 1 . 
     The flag control process in  FIG. 6  is performed by the CPU  102  executing an associated program stored in the ROM  303  or the like. The flag control process in  FIG. 6  is performed in a case where the CPU  102  has acquired from the printer interface  114  the remaining lifetime value of the drum part  201 , which indicates that it is larger than 10%. 
     Referring to  FIG. 6 , first, the CPU  102  determines whether or not the replacement display flag is on (step S 601 ). 
     If it is determined in the step S 601  that the replacement display flag is not on, the CPU  102  terminates the present process. On the other hand, if it is determined in the step S 601  that the replacement display flag is on, the CPU  102  sets the replacement display flag to off (step S 602 ), followed by the CPU  102  terminating the present process. That is, in the variation of the present embodiment, the replacement display flag is set to on during a time period after both the remaining lifetime value of the drum part  201  and that of the toner part  202  were detected to be not larger than 10% and before the remaining lifetime value of the drum part  201  is detected to be larger than 10%. In the MFP  100 , during a time period in which the replacement display flag is on, the message  401  is displayed on the console section  116 . 
     By performing the flag control process described above with reference to  FIG. 6 , the display control process in  FIG. 5  causes the message  401  to be displayed on the console section  116  during the time period after both the remaining lifetime value of the drum part  201  and that of the toner part  202  were detected to be not larger than 10% and before the remaining lifetime value of the drum part  201  is detected to be larger than 10%. That is, the message  401  is displayed on the console section  116  after the notification for prompting replacement of both the drum part  201  and the toner part  202  was provided and before the drum part  201  is replaced. With this, in timing at which the drum part  201  and the toner part  202  should be replaced at the same time, even if the user forgets to replace the drum part  201 , it is possible to cause the user to be aware, before the drum part  201  reaches its lifetime limit, that it is required to replace the drum part  201  as well. 
     In the above-described embodiment, during the time period in which the replacement display flag is on, not only the message  401  but also any other suitable message may be displayed on the console section  116  according to the remaining lifetime value of the toner part  202 . For example, as shown in  FIG. 7 , in the case where the remaining lifetime value of the toner part  202  is larger than 10% and also not larger than 20%, not only the message  401  but the message  403  is displayed on the console section  116 . Further, in the case where the remaining lifetime value of the toner part  202  is not larger than 10%, not only the message  401  but also the message  404  is displayed on the console section  116 . With this, during the time period in which the replacement display flag is on, it is possible provide a notification relevant to replacement of the toner part  202  by a message with appropriate contents, according to the remaining lifetime value of the toner part  202 . 
     Other Embodiments 
     Embodiment(s) of the present invention can also be realized by a computer of a system or apparatus that reads out and executes computer executable instructions (e.g., one or more programs) recorded on a storage medium (which may also be referred to more fully as a ‘non-transitory computer-readable storage medium’) to perform the functions of one or more of the above-described embodiment(s) and/or that includes one or more circuits (e.g., application specific integrated circuit (ASIC)) for performing the functions of one or more of the above-described embodiment(s), and by a method performed by the computer of the system or apparatus by, for example, reading out and executing the computer executable instructions from the storage medium to perform the functions of one or more of the above-described embodiment(s) and/or controlling the one or more circuits to perform the functions of one or more of the above-described embodiment(s). The computer may comprise one or more processors (e.g., central processing unit (CPU), micro processing unit (MPU)) and may include a network of separate computers or separate processors to read out and execute the computer executable instructions. The computer executable instructions may be provided to the computer, for example, from a network or the storage medium. The storage medium may include, for example, one or more of a hard disk, a random-access memory (RAM), a read only memory (ROM), a storage of distributed computing systems, an optical disk (such as a compact disc (CD), digital versatile disc (DVD), or Blu-ray Disc (BD)™), a flash memory device, a memory card, and the like. 
     While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions. 
     This application claims the benefit of Japanese Patent Application No. 2017-048821 filed Mar. 14, 2017 which is hereby incorporated by reference herein in its entirety.