JP6659110B2 - Image forming device - Google Patents

Description

  The present invention relates to an image forming apparatus including a plurality of image forming units of the same color.

  2. Description of the Related Art Conventionally, an image forming apparatus provided with a plurality of image forming units of the same color has been known (Japanese Patent Application Laid-Open No. H10-163873). In such an image forming apparatus, when an image forming unit to be used has a toner-less state in which the remaining amount of toner is equal to or less than a predetermined amount, switching to another unit enables continuous image formation. Further, when the toner remaining amount of the toner bottle corresponding to the image forming unit in use is reduced and the replacement time is approached, the toner concentration of the next image forming unit to be used becomes parallel at the timing of executing the toner concentration adjustment control. May be adjusted and controlled. Thereby, for example, it is possible to suppress the occurrence of the unusable time of the device (hereinafter, referred to as “downtime”).

JP 2011-247933 A

  By the way, when the power is off (including the power saving mode), it is not possible to detect that the toner bottle has been replaced. Therefore, conventionally, every time the power is turned on, the toner bottle of the image forming unit in which the absence of toner is detected is turned to confirm whether or not the toner bottle has been replaced with a new one. In such a case, the input of the job is permitted after the replacement of the toner bottle is detected and the toner absence state is released.

  However, when an image forming unit without toner occurs due to such handling, image formation cannot be performed until the confirmation of replacement of the toner bottle is completed every time the power is turned on, and downtime is reduced. There is a problem that occurs.

  SUMMARY OF THE INVENTION It is an object of the present invention to provide an image forming apparatus capable of reducing downtime caused by waiting for confirmation of toner bottle replacement.

In order to solve the above-mentioned problem, an image forming apparatus according to claim 1 includes a photoconductor, an exposure unit that forms an electrostatic latent image on the photoconductor, and a developing unit that develops the electrostatic latent image formed on the photoconductor. A plurality of image forming units for forming an image of the same color, the developing unit including a developing unit that supplies the developer to the developing unit, and a developer container that supplies the developer to the developing unit. Rotating means for respectively rotating the storage containers, determining means for determining the presence or absence of the developer in the storage container, and controlling the determination means to determine the presence or absence of the developer in the corresponding storage container. When at least one of the determination units determines that the developer is present in the storage container, the image forming unit including the storage container determined to have the developer is used to start forming an image. Present If there is a container that is determined to have no developer, in parallel with the formation of the image, it is determined whether or not the container that has been determined to have no developer by the determination unit has been replaced with a container that has developer. And control means for performing exchange confirmation processing .

According to the present invention, because it forms an image using an image forming means having a container where it is determined that there is a current image agent, reducing the downtime caused by the pending verification of container exchange it can.

1 is a front view of an image forming system including an image forming apparatus according to an embodiment. FIG. 2 is a sectional view illustrating a schematic configuration of the image forming apparatus in FIG. 1. FIG. 2 is a block diagram illustrating a control configuration of the image forming system of FIG. 1. 3 is a flowchart illustrating a procedure of a print job transmission process executed by the image forming system of FIG. 1. 3 is a flowchart illustrating a procedure of a printing process executed by the image forming apparatus of FIG. 2; 6 is a flowchart illustrating a procedure of selecting and printing a bottle with toner, which is executed in step S205 of FIG. 5. 6 is a flowchart illustrating a procedure of a toner bottle replacement confirmation process executed in step S206 of FIG. 8 is a flowchart illustrating a procedure of a bottle rotation process executed in step S404 in FIG. FIG. 7 is a diagram for explaining effects of the present embodiment, and is a timing chart comparing the present embodiment with a conventional technique.

  Hereinafter, embodiments will be described in detail with reference to the drawings.

  FIG. 1 is a front view of an image forming system including an image forming apparatus according to an embodiment.

  In FIG. 1, an image forming system 1000 includes a document reading device 200 having an automatic sheet feeding device, an image forming device 100, and a user interface (UI) device 600.

  The document reading device 200 reads a document placed on a platen glass and outputs image data. The image forming apparatus 100 forms an image on a recording material (paper) in accordance with image data output from the document reading apparatus 200 and image data input from an external device connected via a network. The UI device 600 has, for example, a liquid crystal display with a touch panel, and accepts a user input operation such as presentation of information to a user and designation of the number of prints through a GUI (graphical user interface).

  Hereinafter, the image forming apparatus 100 will be described.

  FIG. 2 is a sectional view showing a schematic configuration of the image forming apparatus in FIG.

  In FIG. 2, an image forming apparatus 100 is a tandem-type intermediate transfer type printer in which a plurality of process units are arranged. The image forming apparatus 100 includes an image forming unit, a transfer unit, a paper storage unit, and a transport unit that transports the paper in the paper storage unit to the paper discharge unit via the transfer unit.

  The image forming unit includes a plurality of process units 101a to 101d. The process units 101a to 101d are process units of the same color, for example, black. Each of the process units 101a to 101d has the same configuration. The configuration of the process units 101a to 101d will be described by exemplifying the configuration of the process unit 101a.

  The process unit 101a includes a photosensitive drum 102a, a developing device 105a disposed around the photosensitive drum 102a, a laser scanner unit 104a as an exposure device, and a charging roller 103a. The process unit 101a includes a primary transfer roller 107a and an auxiliary charging brush 109a provided so as to contact the photosensitive drum 102a via an intermediate transfer belt 108 described later.

  The photosensitive drum 102a as a photosensitive member is driven to rotate by a drum motor (not shown). The charging roller 103a applies a high voltage to uniformly charge the surface of the photosensitive drum 102a. The laser scanner unit 104a scans the laser modulated and output from the laser diode in the longitudinal direction using a polygon mirror rotator, thereby forming an electrostatic latent image on the photosensitive drum 102a according to input image information.

  The corresponding toner bottle unit 106a is connected to the developing device 105a. The developing device 105a develops the electrostatic latent image on the photosensitive drum 102a with a two-component developer including a toner and a carrier to form a visible toner image. The toner bottle unit 106a includes a toner bottle (container) filled with toner and a toner conveying mechanism, and supplies the toner to the corresponding developing device 105a. Note that the toner bottle is configured to be detachable and replaceable from the image forming apparatus 100.

  The primary transfer roller 107a primarily transfers the toner image on the photosensitive drum 102a to an intermediate transfer belt 108 described later. The auxiliary charging brush 109a charges the untransferred toner on the photosensitive drum 102a, which cannot be completely transferred to the intermediate transfer belt 108, to a uniform charge by the primary transfer roller 107a.

  An intermediate transfer belt 108 that rotates so as to contact the photosensitive drums 102a to 102d of the process units 101a to 101d is disposed below the image forming unit. The intermediate transfer belt 108 is formed of an endless belt-like member, and is supported rotatably by being wound around various rollers including the secondary transfer inner roller 110a. An outer secondary transfer roller 110b is arranged so as to contact the inner secondary transfer roller 110a via the intermediate transfer belt 108. The nip between the inner secondary transfer roller 110a and the outer secondary transfer roller 110b is the secondary transfer unit 110. An intermediate transfer body cleaner 111 and a pattern density sensor 112 are arranged at predetermined positions so as to face the intermediate transfer belt 108 that is driven to rotate.

  The toner images transferred onto the intermediate transfer belt 108 by the primary transfer rollers 107a to 107d are secondarily transferred to the sheet P at a secondary transfer unit. The transfer residual toner that has not been completely transferred in the secondary transfer portion and the adjustment toner image that is not intended to be transferred onto the paper P are collected by the intermediate transfer body cleaner 111. The pattern density sensor 112 detects a change in the density of a pattern formed on the intermediate transfer belt 108.

  At the bottom of the image forming apparatus 100, a paper storage unit is arranged. The sheet storage unit includes sheet cassettes 113, 125, and 126. Each sheet cassette stores sheets P of a predetermined size.

  A transport unit is provided from each paper cassette in the paper storage unit to the paper discharge unit 147 via the secondary transfer unit 110 and the fixing device 116. The transport path as a transport unit includes paper feed rollers 114, 127, and 128 corresponding to each paper cassette, and a registration roller 115, and reaches the fixing device 116 via the secondary transfer unit 110. The transport section on the downstream side of the fixing device 116 is a paper discharge path 120. The paper discharge path 120 includes paper discharge ports O1, O2, and O3.

  The transport unit also includes a two-sided reversing path 122 and a two-sided re-feeding path 124 for transporting the sheet reversed by the two-sided reversing path 122 to the secondary transfer unit 110 again. Sheet detection sensors 140, 141, 142, 143, 144, 145, and 146 are provided at predetermined positions of the conveyance path, and are used for sheet conveyance control and detection of a jam state.

  The paper P stored in the paper cassette 113 is conveyed by a paper feed roller 114, corrected for skew by a registration roller 115, and then sent to the secondary transfer unit 110. The paper P on which the toner image has been transferred by the secondary transfer unit 110 is thermally fixed by a fixing device 116 including a fixing roller 117 and a pressure roller 118. The sheet P on which the toner image has been thermally fixed is conveyed to the sheet ejection path 120 by the sheet ejection flapper 119 and then sent to the sheet ejection ports O 1, O 2, O 3 or the two-side inversion path 122 via the sheet ejection path 120. .

  The sheet P sent to the two-sided inversion path 122 is sent to the two-sided re-feeding path 124 by the reverse rotation of the transport rollers and the rotation of the two-sided inversion flapper 123 in the two-sided inversion path 122, and after the image is formed on the second surface, The sheet is discharged to the sheet discharge ports O1, O2, or O3. The sheet P conveyed to the sheet discharge port O1, O2, or O3 is discharged out of the apparatus by the sheet discharge rollers 131, 132, or 133. The paper cassettes 125 and 126 are additional paper cassettes, and the paper stored in the additional paper cassettes 125 and 126 is similarly fed and conveyed.

  Next, a control configuration of the image forming system 1000 will be described. FIG. 3 is a block diagram showing a control configuration of the image forming system 1000 of FIG.

  3, the image forming system 1000 includes a job management CPU circuit unit 800, a UI device control unit 820, a document reading device control unit 840, an image formation control CPU circuit unit 900, and an image forming device control unit 910. The job management CPU circuit unit 800 includes a CPU 801, a ROM 802, and a RAM 803. The CPU 801 controls the UI device control unit 820 and the document reading device control unit 840. The ROM 802 stores a program for operating the CPU 801. The RAM 803 has a backup storage function, and is used to temporarily store a result calculated by the CPU.

  Similarly, the image forming control CPU circuit unit 900 includes a CPU 901, a ROM 902, and a RAM 903. The CPU 901 exchanges jobs and image data with the CPU 801 and controls the image forming apparatus control unit 910. The ROM 902 stores a program for operating the CPU 901. The RAM 903 has a backup storage function, and is used to temporarily store a result calculated by the CPU 901.

  The UI device control unit 820 controls the UI device 600 and exchanges signals relating to job operations with the CPU 801. Document reading device control section 840 controls document reading device 200 and transmits image data obtained by reading a document to CPU 801.

  The image forming apparatus control unit 910 drives a drum motor (not shown) according to a control signal from the CPU 901. The image forming apparatus control unit 910 controls units related to image formation, such as the process units 101a to 101d, the toner bottle units 106a to 106d, the remaining toner sensors 904a to 904d, and the toner bottle motors 905a to 905d.

  The toner bottle unit 106 is configured to supply a toner to the corresponding process unit 101 by driving a bottle rotation motor (905). Then, by detecting the toner supplied from the bottle by the remaining toner sensors 904a to 904d provided on the supply path, it is determined whether the toner remains in the toner bottle (in the container). That is, the remaining toner sensors 904a to 904d are provided on a supply path that connects the toner bottle and the developing device 105 to which the toner bottle is connected. Then, the toner remaining amount sensor 904 determines whether or not toner is supplied from the toner bottle to the developing device 105, and determines whether or not the toner bottle is a bottle with toner based on the determination result.

  Further, the image forming apparatus control unit 910 drives the paper feed rollers 114, 127, 128 by a paper feed / convey motor (not shown), whereby units such as the paper cassettes 113, 125, and 126 related to paper conveyance are controlled. You. In addition, a fixing motor 117 (not shown) drives the fixing roller 117 and the pressure roller 118, and a unit related to the fixing operation such as heating the fixing roller 117 and the pressure roller 118 by the fixing heater is controlled.

  Hereinafter, the operation of the image forming apparatus according to the present embodiment will be described. If there is a toner-containing process unit when the power is turned on, the image forming apparatus 100 performs a toner bottle replacement confirmation operation corresponding to the toner-less process unit in parallel with the printing operation.

  FIG. 4 is a flowchart illustrating a procedure of a print job transmission process executed by the image forming system 1000 of FIG. This print job transmission processing is executed by the CPU 801 of the image forming system 1000 in accordance with the print job transmission processing program stored in the ROM 802.

  4, when the power is turned on to the image forming system 1000 and the print job transmission process is started, the CPU 801 first performs a predetermined activation process (step S101). As the start-up processing, for example, control is performed to display the UI device control unit 820 on a screen. Next, the CPU 801 turns on the power of the image forming control CPU circuit unit 900 (step S102). The operation of the CPU 901 of the image forming control CPU circuit unit 900 will be described later with reference to a flowchart shown in another figure.

  Next, the CPU 801 waits for communication from the CPU 901 and checks whether or not the activation of the CPU 901 is completed, and waits until the activation of the CPU 901 is completed (step S103). After confirming that the activation of the CPU 901 has been completed by communication from the CPU 901, the CPU 801 advances the process to step S104. That is, the CPU 801 confirms whether or not the CPU 901 has notified that printing is possible (with toner), and waits until the notification of printing is notified (step S104). Communication between the CPU 801 and the CPU 901 may be performed by any means, for example, by exchanging an arbitrary bit string by serial communication.

  If the result of determination in step S104 is that printing is possible, CPU 801 determines whether or not a job has been submitted by the user, and waits until a job has been submitted (step S105). The job is input by the user inputting a print start instruction to the UI device control unit 820.

  Next, after the job is input by the user (“YES” in step S105), the CPU 801 transmits print job information to the CPU 901 (step S106), and ends the print job transmission processing.

  According to the processing in FIG. 4, when the image forming apparatus 100 is capable of printing (“YES” in step S104), the CPU 801 transmits a print job to the CPU 901.

  Next, a printing process performed by the image forming apparatus 100 of FIG. 2 will be described.

  FIG. 5 is a flowchart illustrating a procedure of a print process executed by the image forming apparatus 100 of FIG. This printing process is different from the process in FIG. 4 and is executed by the CPU 901 of the image forming control CPU circuit unit 900 according to a printing process program stored in the ROM 902.

  In FIG. 5, when the power of the image forming apparatus 100 is turned on, the CPU 901 first performs a predetermined activation process (step S201). Examples of the start-up process include a communication process for notifying the CPU 801 that the CPU 901 has started. Next, the CPU 901 determines whether or not there is at least one process unit having a toner bottle in a state where the remaining toner sensor 904 detects the presence of toner (step S202). At this time, the CPU 901 determines whether or not toner is present only by the reaction state of the toner remaining amount sensor (904) without rotating the bottle.

  If the result of determination in step S202 is that there is at least one process unit having a toner bottle with toner ("YES" in step S202), the CPU 901 advances the process to step S203.

  That is, the CPU 901 notifies the CPU 801 that printing is possible (with toner) (step S203). Next, the CPU 901 determines whether or not a print job transmitted from the CPU 801 having received the notification that printing is possible has been received, and waits until the print job is received (step S204). After receiving the print job from the CPU 801, the CPU 901 starts the process of selecting a process unit having a toner bottle with toner and performing a printing process (hereinafter, “selection and printing process of a bottle with toner”) (step S 205). . Details of the processing executed in step S205 will be described later as a subroutine.

  After the printing process is started, the CPU 901 executes a toner bottle replacement confirmation process for determining whether or not the toner bottle determined to have no remaining toner in step S202 has been replaced, in parallel with the image forming operation (step S202). S206). Here, the toner bottle determined to have no toner is a toner bottle determined to have no toner provided in a process unit other than the process unit applied to the print processing.

  That is, the CPU 901 rotates the toner bottle of the process unit having the toner bottle determined to have no remaining toner in step S202, and executes a toner bottle replacement confirmation process to determine whether the toner bottle has been replaced. The specific contents of the toner bottle replacement confirmation processing will be described later as a subroutine. After executing the toner bottle replacement confirmation process (step S206), the CPU 901 determines whether the print job has ended, and waits until the print job ends (step S207). Then, after the print job is completed, the present process is completed.

  On the other hand, if the result of determination in step S202 is that there is no process unit with a toner bottle with toner ("NO" in step S202), CPU 901 notifies CPU 801 that printing is not possible (no toner). Notify (step S210). Next, the CPU 901 rotates the toner bottle corresponding to the process unit without toner and determines whether or not the toner bottle has been replaced (step S211). The determination as to whether the toner bottle has been replaced is made based on whether the toner bottle is rotated and toner is supplied from the toner bottle. That is, when the toner bottle is rotated and toner is supplied from the toner bottle, it is determined that the toner bottle without toner has been replaced with a toner bottle with toner.

  Next, the CPU 901 determines whether or not there is at least one process unit having a toner bottle in a state where the remaining toner sensor 904 detects the presence of toner (step S212). As a result of the determination in step S212, if there is at least one process unit having the toner bottle in a state where the presence of toner is detected (“YES” in step S212), the CPU 901 returns the process to step S203. On the other hand, as a result of the determination in step S212, when there is no process unit including the toner bottle in a state where the presence of toner is detected (“NO” in step S212), the CPU 901 ends this processing.

  According to the processing in FIG. 5, after the start of the image forming apparatus 100, it is determined whether or not there is at least one process unit having a toner bottle in a toner-present state (step S202). If there is at least one process unit having a toner bottle with toner, print processing is first started using the process unit with a toner bottle with toner (step S205). As a result, it is possible to reduce downtime caused by waiting for confirmation of toner bottle replacement.

  Further, according to the present embodiment, after the printing process is started (step S205), the toner bottle replacement confirmation process is executed in parallel (step S206). Thus, it is possible to confirm whether or not the toner bottle without toner has been replaced with the toner bottle with toner while executing the print processing.

  Next, the selection and printing process of the bottle with toner executed in step S205 of FIG. 5 will be described.

  FIG. 6 is a flowchart showing the procedure of selecting and printing a bottle with toner executed in step S205 of FIG. The selection and print processing of the bottle with toner are performed by the CPU 901 of the image forming control CPU circuit unit 900 according to the selection and print processing program of the bottle with toner stored in the ROM 902 as in the job execution processing of FIG.

  In FIG. 6, when the selection of the bottle with toner and the printing process are started, the CPU 901 determines whether or not the toner bottle 1 is in the state with toner (detecting the presence of toner) (step S301). If the result of determination in step S301 is that toner bottle 1 is in a toner-present state ("YES" in step S301), CPU 901 advances the process to step S302. That is, the CPU 901 selects a process unit corresponding to the toner bottle 1 as a process unit used for image formation (step S302). Next, the CPU 901 starts a predetermined printing operation using the process unit corresponding to the toner bottle 1 (step S303), and ends this processing after the printing operation is completed.

  On the other hand, if the result of determination in step S301 is that toner bottle 1 is not in a toner-present state ("NO" in step S301), CPU 901 advances the process to step S311. That is, the CPU 901 determines whether or not the toner bottle 2 is in a state with toner (step S311). If the toner bottle 2 is in the toner-present state (“YES” in step S311), the CPU 901 selects a process unit corresponding to the toner bottle 2 as a unit used for image formation (step S312). Next, the CPU 901 performs a predetermined print operation using the process unit corresponding to the toner bottle 2 (step S303), and ends this processing after the print operation ends.

  If the result of determination in step S311 is that toner bottle 2 is not in a toner-present state ("NO" in step S311), CPU 901 advances the process to step S321. That is, the CPU 901 determines whether or not the toner bottle 3 is in a state with toner (step S321). If the toner bottle 3 is in the toner-present state (“YES” in step S321), the CPU 901 selects a process unit corresponding to the toner bottle 3 as a unit used for image formation (step S322). Next, the CPU 901 performs a predetermined print operation using the process unit corresponding to the toner bottle 3 (step S303), and ends this process after the print operation is completed.

  On the other hand, if the result of determination in step S321 is that toner bottle 3 is not in the toner-present state ("NO" in step S321), in this case, the determination in step S202 in FIG. Accordingly, the CPU 901 selects the process unit corresponding to the toner bottle 4 as a unit to be used for image formation (step S332), and then the CPU 901 selects the process unit corresponding to the toner bottle 4. Then, a predetermined print operation is executed (step S303), and after the print operation is completed, this processing is completed.

  According to the process of FIG. 6, among the determination targets, the process unit corresponding to the toner bottle determined to have toner first is selected as the process unit used for the image forming operation (steps S302, S312, S322, and S332). . Then, print processing is executed using the selected process unit. As a result, the printing process can be started immediately after the power is turned on without exchanging the tonerless bottle, so that downtime caused by waiting for confirmation of toner bottle exchange can be reduced.

  Next, the toner bottle replacement confirmation processing executed in step S206 in FIG. 5 will be described. FIG. 7 is a flowchart showing the procedure of the toner bottle replacement confirmation process executed in step S206 of FIG. The toner bottle replacement confirmation process determines whether the toner bottle determined to have no remaining toner in the toner bottle by the remaining toner sensor 904 has been replaced with a toner bottle having a remaining toner, for example, a new toner bottle. It is for confirmation. The toner bottle replacement confirmation processing is executed by the CPU 901 incorporated in the image forming control CPU circuit unit 900 of the image forming apparatus 100 in accordance with the toner bottle replacement confirmation processing program stored in the ROM 902, similarly to the print processing of FIG.

  7, when the toner bottle replacement confirmation process is started, the CPU 901 first initializes a variable N for identifying a toner bottle with 1 (step S401). Next, the CPU 901 determines whether or not the rotation history Rn of the toner bottle N, for example, N = 1, is equal to or lower than a predetermined rotation speed (step S402). Rn is a variable unique to each toner bottle, and corresponds to the number of rotations after the toner remaining amount sensor detects that there is no toner. The Rn count-up process will be described later with reference to FIG. After the toner remaining amount sensor 904 detects that there is no toner, the predetermined rotation speed T is replaced with a new toner bottle, toner is supplied to the developing device 105 by the replaced toner bottle, The number of rotations is sufficient for the sensor to detect the presence of toner. The predetermined rotation number T is, for example, 30 times.

  As a result of the determination in step S402, if the rotation history Rn of the toner bottle N is equal to or less than the predetermined rotation number T ("YES" in step S402), the CPU 901 advances the process to step S403. That is, the CPU 901 determines whether or not the toner remaining amount sensor 904 corresponding to the toner bottle N has detected that there is no toner (step S403). If the result of the determination in step S403 is that the toner remaining amount sensor 904 corresponding to the toner bottle N has detected that there is no toner ("YES" in step S403), the CPU 901 advances the process to step S404. That is, the CPU 901 rotates the toner bottle N to check whether toner is supplied from the toner bottle N (toner bottle rotation process) (step S404).

  Next, the CPU 901 adds 1 to a variable N for identifying a toner bottle (step S405). After adding 1 to the variable N, the CPU 901 determines whether or not the variable N after adding 1, for example, 4 has exceeded a predetermined total number Nmax of bottles (step S406). As a result of the determination in step S406, when the variable N exceeds Nmax (“YES” in step S406), the CPU 901 advances the process to step S407. That is, the CPU 901 continues the printing operation started in step S205 in FIG. 5 (step S407), and thereafter ends the toner bottle replacement confirmation processing.

  On the other hand, as a result of the determination in step S406, if the variable N does not exceed Nmax (“NO” in step S406), the CPU 901 returns the process to step S402, and similarly performs the exchange confirmation process for another toner bottle. Execute.

  If the result of the determination in step S402 indicates that the rotation history Rn exceeds the predetermined number of rotations T ("NO" in step S402), the CPU 901 advances the process to step S405. If the result of the determination in step S403 is that the toner bottle N is in a toner-present state ("NO" in step S403), the CPU 901 stops the rotation of the bottle N (step S411), and then proceeds to step S412. Proceed to That is, the CPU 901 initializes the rotation history Rn to 0 (step S412), and thereafter advances the processing to step S405.

  According to the processing of FIG. 7, when the rotation history Rn is equal to or less than the predetermined rotation number T and it is determined that the toner bottle N has no toner (“YES” in step S403), it is determined whether toner is supplied from the toner bottle N. (Step S404) By further rotating the toner bottle N, if there is toner in the toner bottle N, the toner is supplied from the toner bottle N. This is detected. By doing so, it is possible to confirm whether or not the toner bottle has been replaced.

  FIG. 8 is a flowchart illustrating the procedure of the bottle rotation process executed in step S404 in FIG. The bottle rotation processing is executed by the CPU 901 incorporated in the image forming control CPU circuit unit 900 according to a bottle rotation processing program stored in the ROM 902.

  The bottle rotation process is a process started by an interrupt signal issued to the CPU 901 when a bottle rotation detection sensor (not shown) provided for each bottle unit 106 makes one rotation of the bottle.

  When the bottle rotation process is started, the CPU 901 adds 1 to the rotation history Rn of the toner bottle N each time an interrupt signal is received from the bottle rotation detection sensor (step S501), and then stops the rotation of the toner bottle N. (Step S502). In this way, Rn is counted up at the timing of one rotation from the start of rotation of the toner bottle N, the rotation of the bottle is stopped once, and the flow ends. Then, the process proceeds to steps S402 and S403 in FIG. 7, and the presence or absence of toner is determined by the remaining toner sensor.

  According to the process of FIG. 8, when the rotation history Rn of the toner bottle N is equal to or less than the predetermined rotation speed T and it is determined that the toner bottle N has no toner (“YES” in step S403), the toner is discharged from the toner bottle N. The toner bottle N is rotated again to determine whether or not the toner is supplied. This makes it possible to accurately confirm the replacement of the toner bottle determined to be out of toner with a new one.

  According to the present embodiment, in an image forming apparatus having a plurality of process units of the same color, if at least one unit has toner immediately after the power is turned on, a job is executed, and a unit which is also detected as having no toner is executed. Execute toner bottle replacement confirmation processing. As a result, it is possible to reduce downtime caused by waiting for toner bottle replacement confirmation.

  Hereinafter, effects of the present embodiment will be described in comparison with the related art.

  FIG. 9 is a diagram for explaining the effect of the present embodiment, and is a timing chart comparing the present embodiment with the related art.

  In FIG. 9, timings related to the system state, bottle rotation operation, and toner remaining amount detection from when the power of the image forming apparatus in the power-off state is turned on until a print job is input and a predetermined print is completed. ing.

  FIG. 9A is a timing chart according to the present embodiment, and FIG. 4B is a timing chart according to the related art.

  First, a common part between FIGS. 4A and 4B will be described. When the power is turned off, power is not supplied, the rotation of the toner bottle is stopped, and the remaining toner amount sensor 904 is in an invalid state, so that the remaining toner amount is unknown.

  When the power is turned on and the power is supplied by the user, the image forming apparatus 100 performs a predetermined startup process such as excitation of a motor. At this time, the toner remaining amount sensor 904 is in the valid state. However, even if the toner bottle without toner is replaced when the image forming apparatus 100 is in the power-off state, the toner remaining amount sensor 904 is in the invalid state. Not detected. Therefore, even if the toner remaining amount sensor 904 does not detect the presence of the toner, the remaining amount of the toner is in an unknown state because the bottle may be replaced.

  After the predetermined startup processing is completed, the behavior of the present embodiment (FIG. 4A) is clearly different from that of the conventional technique (FIG. 4B).

  That is, in the case of the present embodiment (FIG. 4A), printing can be started immediately upon completion of activation, and the system state is a job waiting state. When a job is input, for example, printing is started using the toner bottle 2, and the bottle whose toner remaining amount is unknown (toner bottle 1) is rotated to try to check whether or not it has been replaced. Then, the reaction of the toner remaining amount sensor is confirmed. If the toner bottle has been replaced, the toner is supplied, and the remaining toner amount is detected by the toner remaining amount sensor, so that it is determined that the bottle has been replaced.

  In this case, since the process unit having the toner bottle 2 is used for printing, the printing operation can be performed without being affected by the toner replacement confirmation operation of the toner bottle 1. As described above, in the present embodiment, the bottle replacement confirmation operation and the print job operation in the state where the remaining amount of toner is unknown after the power is turned on are executed in parallel. Can be reduced.

  On the other hand, in the case of the conventional technique (FIG. 4B), after the start-up is completed, first, a bottle replacement confirmation operation is performed. Therefore, during the bottle replacement confirmation operation, the job submission is not accepted or the job submission is suspended, and then the printing process is started after the bottle replacement confirmation operation is completed. Therefore, downtime due to the toner bottle replacement confirmation process cannot be avoided.

  In the present embodiment, it is preferable that CPU 901 of image forming apparatus control unit 910 notify the user to replace the toner bottle determined to have no remaining toner with a toner bottle having toner. Thus, downtime at the time of next power-on can be reduced.

  In the above embodiment, the total number of toner bottles and process units has been described as 4. However, the present invention may be applied to any image forming apparatus having a plurality of process units of the same color regardless of the total number of process units. Can be. Also, the embodiment using the rotation detection sensor with the rotation number of the toner bottle as an index has been described. For example, a rotation time is used instead of the rotation number of the toner bottle, and a timer circuit is used instead of the rotation detection sensor. You can also.

  In the present embodiment, the bottle rotation means, the bottle rotation control means, and the like are not limited to each, and any other than the above can be applied.

Reference Signs List 100 Image forming apparatus 101 Process unit 102a Photosensitive drum 104a Laser scanner unit 106 Toner bottle unit 801 CPU
901 CPU
904 Toner remaining sensor

Claims (8)

A photoconductor, an exposure unit for forming an electrostatic latent image on the photoconductor, a developing unit for developing the electrostatic latent image formed on the photoconductor, and a container for supplying a developer to the developing unit. A plurality of image forming means for forming an image of the same color provided,
Rotating means for respectively rotating the storage containers to supply developer from the storage container to the developing means,
Determining means for determining the presence or absence of the developer in the storage container,
The control unit controls the determination unit to determine the presence or absence of the developer in the corresponding storage container. When at least one of the determination units determines that the storage container has the developer, the storage unit determines that the developer is present. An image is started to be formed using the image forming unit provided with the container, and if there is a storage container that has been determined to have no developer by the determining unit, the developing unit determines that there is no developer in parallel with the image formation. Control means for performing exchange confirmation processing for confirming whether or not the storage container determined to have been replaced with a storage container with developer ;
An image forming apparatus comprising:   The control means, when the first determination target container is determined by the determination means that there is a developer, using the image forming means provided with the first determination target storage container, the image forming means The image forming apparatus according to claim 1, wherein control is performed to form the image.   The control unit is configured to, when the determination unit determines that the first container to be determined does not have the developer, to store the developer first determined to be the developer among the next container to be determined. 3. The image forming apparatus according to claim 1, wherein control is performed to form the image using an image forming unit having a container. The control means determines whether or not the rotation speed based on the rotation history of the storage container is equal to or less than a predetermined rotation speed in the exchange confirmation processing, and determines whether the rotation speed is equal to or less than the predetermined rotation speed, and If it is not determined agent is with claim 1, characterized in that to further rotate the determination that was not storage container and has the developer by controlling the rotating means container has not been determined to have the developer The image forming apparatus according to any one of claims 1 to 3 . The control unit is configured to store the developer container with the developer when the determination unit determines that the developer is present even when the rotation speed based on the rotation history of the storage container is equal to or less than the predetermined rotation speed. The image forming apparatus according to claim 4 , wherein the image forming apparatus is regarded as being replaced with a container. In the exchange confirmation processing, when the rotation speed based on the rotation history of the storage container exceeds a predetermined rotation speed, the control unit may determine whether the storage container has been stored based on a determination result of the determination unit corresponding to the storage container. the image forming apparatus according to claim 4 or 5, wherein the determining the presence or absence of the developer in the container. Said control means, said exchange confirmation processing, when the power supply is turned on, according to any one of claims 1 to 6, characterized in that to perform all of the container it is determined that there is no developer Image forming apparatus. In the replacement confirmation processing, the control unit may notify a user to replace a storage container that has not been replaced with a storage container with a developer with a storage container with a developer. the image forming apparatus according to any one of claims 1 to 7.