JP5423065B2 - Seal member detection apparatus, image forming apparatus, and seal member detection program - Google Patents

Description

  The present invention relates to a seal member detection device, an image forming apparatus, and a seal member detection program.

  In an image forming apparatus, when an electrostatic latent image formed on a photosensitive drum is developed using a two-component developer developed with toner and carrier, the developing apparatus has a predetermined ratio of toner and carrier. Filled with. This developing device is detachable from the image forming apparatus.

  The developing device is provided with a toner supply port for mainly receiving replenishment of toner consumed by the development, and a developer delivery port for feeding the two-component developer to a developing roll facing the photosensitive drum. However, when the image forming apparatus main body is shipped or when the developing apparatus is transported alone, seal members are respectively attached to the toner supply port and the developer supply port.

  The seal member is peeled off from the developing device by an operator (user or installation manager, etc.) immediately after loading the developing device after installing the image forming apparatus. By peeling off the seal member, the developing device can perform the original function of receiving the supply of toner from the toner supply port and sending the developer to the developing roll from the developer delivery port. .

  Here, unless the seal member at the developer delivery port is peeled off, the developer cannot go to the photosensitive drum through the developing roll, and therefore development cannot be performed. On the other hand, if the seal member at the toner supply port is not peeled off, it is possible to develop a processing amount corresponding to the amount of the two-component developer filled in advance.

  For reference, Patent Document 1 and Patent Document 2 disclose detecting forgetting to remove a protective member attached to an image forming cartridge using a toner concentration detection sensor.

  The detection target of Patent Document 1 is a photosensitive member protection member, and the detection target of Patent Document 2 is provided between the developer storage unit and the developer carrier (that is, the outlet side) and a two-component developer is provided. It is a seal member that seals in the developer accommodating portion.

No. 7-55571 JP 2000-267424 A

  The present invention provides a seal member detection device, an image forming apparatus, and a seal that can detect forgetting to remove at least a seal member whose opening on the entry side is forgotten, more quickly and more reliably than when this configuration is not provided. The object is to obtain a member detection program.

According to the first aspect of the present invention, the density of a reference image formed every predetermined image forming period is monitored, and forcedly through a toner supply port provided in the developing device as necessary. A forced supply means for supplying toner, and a density of the reference image is higher than a first threshold that is a forced toner supply start level by the forced supply means, and a processing amount of the developing device is defined When the value is less than the value, the density of the reference image is monitored with a third threshold value that is darker than the first threshold value, which is the density of the reference image that requires the forced toner supply. And a discriminating means for establishing a detection mode execution condition for discriminating at least the presence or absence of a seal member attached to the toner supply port when the density of the reference image becomes less than the third threshold value. Member detection device
doing.

According to a second aspect of the present invention, when the reference image is thin as a result of the comparison with the first threshold value, the density of the reference image formed at a predetermined image forming period is targeted. The toner is supplied through a toner supply port provided in the developing device and the density of the reference image formed after the toner is forcibly supplied is set to a value thinner than the first threshold value. As a result of the comparison with the second threshold value, the forced supply control means for stopping the forced supply of the toner when the reference image becomes thin, and the forced supply control means This is executed when the density is higher than the density of the first threshold value, and the density of the reference image is compared with the third threshold value that is darker than the first threshold value. And the reference density becomes less than the third threshold value. When the said to the toner supply opening has mainly determining means to establish the execution condition of the detection mode to determine whether the pasted sealing member for the developer leakage prevention during transport, the.

The invention of claim 3 is the invention of claim 2, wherein on condition that the developing device is in the implementation period of the predetermined processing amount less image forming process, the concentration of the reference image and Seal member detection based on the comparison with the third threshold is executed.

According to a fourth aspect of the present invention, in the second or third aspect of the present invention, when the density of the reference image is lower than a third threshold value, the toner corresponding to the image processing amount is used as the detection mode. The first condition in which the ratio of the forced supply amount exceeds the upper limit, the second condition in which the image density becomes thinner than the lower limit value, and the third condition in which the set value of the image forming condition for the image forming process is larger than the upper limit value When at least one of the conditions is satisfied, or when all of the first condition, the second condition, and the third condition are satisfied, a seal member is attached to the toner supply port. judge.

  According to a fifth aspect of the present invention, the seal member detection device according to any one of the first to fourth aspects is filled with a two-component developer generated by toner and a carrier at a predetermined ratio. A filling portion; a developer delivery port for covering the filling portion and delivering a developer to a developer carrier based on a development process; a housing provided with the toner supply port; and the developer delivery port And a seal member affixed to each of the toner supply ports mainly for preventing leakage of the developer during transportation, and applied as a means for detecting forgetting to remove the seal member of the developing device.

  Invention of Claim 6 is a sealing member detection program for functioning a computer as a sealing member detection apparatus of any one of the said Claims 1-4.

  According to the invention described in claim 1, claim 2, claim 5 or claim 6, as compared with the case where the present configuration is not provided, forgetting to remove the seal member in which at least the entrance opening is sealed, Compared to the case where the configuration is not provided, the detection can be performed quickly and reliably.

  According to the third aspect of the present invention, it is possible to detect forgetting to remove the seal member more quickly than in the case where the present configuration is not provided.

  According to the fourth aspect of the present invention, it is possible to detect forgetting to remove the seal member more reliably than in the case where the present configuration is not provided.

1 is a schematic diagram of an image forming apparatus according to the present embodiment. FIG. 2 is a schematic diagram of a developing unit in the image forming apparatus according to the present embodiment. It is a block diagram which shows the hardware constitutions of the control unit which concerns on this Embodiment. FIG. 6 is a functional block diagram for executing forced toner supply processing, toner cartridge empty detection, and forgetting to remove a seal in a print control management unit according to the present embodiment. 7 is a flowchart for executing a forced toner replenishment mode in a print control management unit according to the present embodiment. 6 is a flowchart for executing a toner cartridge empty detection mode in a print control management unit according to the present embodiment. It is a flowchart which performs the seal member forgetting detection mode in the printing control management part which concerns on this Embodiment.

(overall structure)
As shown in FIG. 1, the image forming apparatus 10 includes a housing 12, and a sheet material supply device 14 is disposed in the lower portion of the housing 12. In addition, a discharge tray 16 for discharging the sheet material on which the image is formed is formed on the top of the housing 12.

  Further, the sheet material supply device 14 is provided with a paper feed cassette 18, and a large number of paper P are stacked and accommodated in the paper feed cassette 18. The paper feed cassette 18 is provided with a bottom plate 20 on which the paper P is stacked. When the paper P is fed to the transfer unit 34 of the photosensitive drum 40 supported by the photosensitive unit 30 described later, the bottom plate 20 is moved upward by lifting means (not shown). Yes. The uppermost sheet P loaded on the bottom plate 20 is pressed against the pickup roll 22. Further, when the paper feeding cassette 18 is pulled out from the housing 12, the bottom plate 20 is moved downward by the elevating means to store the paper P in the paper feeding cassette 18.

  When the paper P is sent to the transfer section 34, the uppermost paper P stacked on the bottom plate 20 is sequentially taken out by the pickup roll 22, and further rotated by the paper feed roll 24 and the separation roll 26. It is designed to be transported one by one.

  The paper P conveyed from the paper feed cassette 18 is temporarily stopped by the registration roller 28, passes between the photosensitive unit 30 and the transfer unit 32 at a predetermined timing, and further fixes the toner image on the paper P. The sheet is discharged to the discharge tray 16 by the discharge roll 38 through the fixing device 36.

  Further, in the housing 12, a photosensitive unit 30, a transfer unit 32, a power supply unit 41, and a control unit 44 are disposed. The photosensitive unit 30 is provided with a photosensitive frame 46, and four photosensitive drums 40 are rotatably supported on the photosensitive frame 46.

  The control unit 44 controls overall image formation (details will be described later).

  As shown in FIG. 1, around each photosensitive drum 40, a charging roll 48 that charges the photosensitive drum 40 like this, and a latent image written on each photosensitive drum 40 with a developer (toner). A developing unit 50 as a developing means for developing, a charge eliminating device 52 for discharging the photosensitive drum 40 after the transfer, and a cleaning as a developer removing means for removing the developer remaining on the photosensitive drum 40 after the transfer is performed. A device 54 is provided.

  The photoconductor unit 30 is a unit in which four photoconductor drums 40, a charging roll 48, a developing unit 50, a static eliminator 52, and a cleaning device 54 are held by a photoconductor frame 46 and integrated. It is detachable with respect to.

  On the other hand, the four toner boxes 56 corresponding to the four developing units 50 are connected to the back side of the photoreceptor unit 30. The toner box 56 is for magenta, yellow, cyan, and black, and includes a toner supply unit 58 and a toner collection unit 60 that are integrated. Further, the toner supply unit 58 is connected to the developing unit 50 and supplies toner of each color to the developing unit 50. The toner collection unit 60 is connected to the cleaning device 54 and collects toner of each color.

  Further, the exposure device 62 that writes a latent image on the photoconductive drum 40 with a laser beam is disposed on the back side of the photoconductive unit 30 at a position corresponding to each photoconductive drum 40 and is uniformly charged. The body drum 40 is irradiated with a laser to form a latent image.

  The transfer unit 32 is disposed on the front side of the photoconductor unit 30 in the vertical direction so as to face the photoconductor unit 30. The transfer unit 32 has two support rolls 64 provided in the vertical direction, a transport belt 66 wound around the two support rolls 64, and the photosensitive drums 40 across the transport belt 66. A transfer roll 68 provided at the position is provided.

  Further, a density sensor 91 is disposed at a position wound around the support roll 64 in the transport belt 66 so as to face the surface with a certain distance from the transport belt 66. The density sensor 91 forms a reference image on the conveyance belt 66, measures the density thereof, adjusts the light amount based on the image data from the exposure device 62 and the development bias voltage in the development unit 50, and conveyance. There is toner density adjustment in which a reference image is formed on the belt 66, the density is measured, and the toner density (toner / carrier) of the two-component developer is adjusted.

  A cleaning device 94 is provided on the transport belt 66 on the downstream side of the support roll 64 in the transport direction. The cleaning device 94 includes a scraper 94S, and the tip of the scraper 94S is in contact with the transport belt 66.

(Details of development unit 50)
FIG. 2 shows the developing unit 50. Since each color has the same configuration, the reference for each color is omitted, and one developing unit 50 will be described as an example, and the description of the other developing units 50 will be omitted.

  The developing unit 50 is provided with a tray-shaped filling unit 110 that stores the two-component developer supplied from the toner supply path. The filling unit 110 is formed as a part of the developing unit housing 112 that forms the outline of the developing unit 50. In addition, a toner supply port 114 that receives supply of toner from a toner cartridge (not shown) is provided at the upper portion of the developing unit housing 112.

  A pair of spiral augers 116 </ b> A and 116 </ b> B are attached to the filling unit 110 such that the longitudinal direction (the depth direction in FIG. 2) is an axis. The pair of spiral augers 116A and 116B has a shape in which spiral blades are attached to the peripheral surface of the shaft rod, and has a role of causing the two-component developer to flow in the axial direction by a screw conveyor system by rotating. doing. The two-component developer has a two-chamber configuration in which the filling portion 110 flows in a ring shape (track shape such as an athletic field) when viewed from the upper surface of FIG.

  That is, the pair of spiral augers 116 </ b> A and 116 </ b> B have directions in which the flow promotion directions are opposite to each other, and the two-component developer is circulated and stirred in the filling unit 110.

  When the image forming process is executed, the two-component developer (toner) is sent out from the filling unit 110 to the developing roll 118. At this time, the development formed on the inner wall of the developing unit housing 112 is performed. It is delivered through the agent delivery port 120.

  Seal members 122A and 122B are attached to the toner supply port 114 and the developer delivery port 120, respectively, and the respective openings are closed.

  The seal members 122A and 122B have a role of preventing leakage of the two-component developer previously filled in the filling unit 110 mainly when the developing unit 50 is transported alone or when the image forming apparatus 10 is shipped. doing.

  For this reason, when the developing unit 50 is loaded into a predetermined position of the image forming apparatus 10, the seal members 122A and 122B need to be peeled off.

(Hardware configuration of control unit)
As shown in FIG. 3, the control unit 44 includes a main control unit 70. The main control unit 70 includes a CPU 72, a RAM 74, a ROM 76, an I / O (input / output unit) 78, and a bus 80 such as a data bus or a control bus for connecting them.

  Connected to the I / O 78 is a print control management unit 88 for controlling and managing each processing system such as a transport system in the image forming apparatus 10, a scanning exposure system for image formation, and a development system. .

  More specifically, the print control management unit 88 is connected to the conveyance control unit 100, the scanning exposure control unit 102, the development control unit 104, the transfer control unit 106, and the fixing control unit 108, and manages the control of each unit. .

  The print control management unit 88 may be configured to be directly connected to the bus 80 instead of the I / O 78. Here, the control related to printing is integrated in the print control management unit 88, but the main control unit 70 may execute the control.

  A UI (user interface) 82 is connected to the I / O 78. The UI 82 has a function of receiving an input instruction from the user and notifying the user of information related to image processing. Further, a hard disk 84 is connected to the I / O 78. The I / O 78 is connected to the communication line network 90 via the I / F 86.

  In this embodiment, the toner density adjustment is performed by forming a reference image for adjusting the toner density and replenishing the toner according to the density detected by the density sensor 91 by the print management control unit 88. Yes. Among them, since the toner density decreases when the remaining amount of toner in the toner cartridge decreases, the toner is forcibly replenished. Nevertheless, since the toner density does not recover when there is almost no remaining toner, it is detected that the toner cartridge is empty.

(Forcible toner replenishment processing / toner cartridge empty detection / detection of forgetting to remove seal)
FIG. 4 is a functional block diagram for executing the forced toner supply process, the toner cartridge empty detection, and the forgetting to remove the seal in the print control management unit 88 described above. Note that this functional block diagram does not limit the hardware configuration of the print control management unit 88, but is classified by function.

  The print control management unit 88 is provided with an image formation execution control unit 150, to which the conveyance control unit 100, scanning exposure control unit 102, development control unit 104, transfer control unit 106, and fixing control unit 108 are connected. (Not shown). The processing status of each control unit is sequentially input to the image formation execution control unit 150 as log information.

  The image formation execution control unit 150 is connected to the log analysis unit 152. The image formation execution control unit 150 outputs the log information to the log analysis unit 152.

  Based on the log information, the log analysis unit 152 outputs a toner density reference image formation instruction to the image formation execution control unit 150 at a predetermined timing. For example, the predetermined timing includes a timing when a predetermined number of sheets (25 sheets) are printed, a timing when the image forming apparatus 10 is turned on, and the like.

  Next, the log analysis unit 152 analyzes that the reference image has been formed from the log information. The log analysis unit 152 is connected to the reference image density reading unit 154. Based on the log information, the log analysis unit 152 outputs a density information reading instruction and toner forcible supply information described later to the reference image density reading unit 154.

  Here, a density sensor 91 is connected to the image formation execution control unit 150. The reference image density reading unit 154 reads density information of the reference image from the density sensor 91 via the image formation execution control unit 150.

  The reference image density reading unit 154 is connected to the first comparison unit 156. Based on the forced supply information, the reference image density reading unit 154 outputs the density information to the first comparison unit 156 before executing the forced supply process described later a plurality of times (three times).

  The first comparison unit 156 is connected to the first threshold value memory 158. The first comparison unit 156 compares the density information with the first threshold value stored in the first threshold value memory 158. The first comparison unit 156 is connected to the forced supply execution availability determination unit 160. The first comparison unit 156 outputs the first comparison result information to the forced supply execution availability determination unit 160.

  Based on the first comparison result information, the forcible supply execution availability determination unit 160 determines whether to execute the forced toner supply process.

  More specifically, when the density of the reference image is less than the first threshold value, execution of the forced toner supply process is determined. As a result, the toner is forcibly supplied into the developing unit 55, and the toner density that has been lowered is increased. Even if the forced replenishment is executed, if the density of the reference image is less than the first threshold value, it is determined that the forced replenishment is repeated again.

  The forced supply execution availability determination unit 160 is connected to the image formation execution control unit 150. Based on the determination, the forced supply execution availability determination unit 160 outputs a start instruction or a repeat instruction for the forced toner supply process to the image formation execution control unit 150. As a result, the image formation execution control unit 150 controls each unit to execute the forced toner supply process.

  On the other hand, when all the toner in the toner cartridge is consumed, no more toner is supplied, so the toner density decreases as printing is performed. When this is detected, an instruction to start the toner forcible supply process is issued. However, when the toner cartridge is empty, even if the start instruction is given, the toner is not supplied and the toner density does not increase. Therefore, in this embodiment, the forced toner supply process is not repeated more than the set number of times.

  Here, the reference image density reading unit 154 is connected to the second comparison unit 162. The reference image density reading unit 154 outputs the density information to the second comparison unit 162 after executing the forced supply process a plurality of times (three times) based on the forced supply information.

  The second comparison unit 162 is connected to the second threshold memory 164. The second comparison unit 162 compares the density information with the second threshold value stored in the second threshold value memory 164. The second comparison unit 162 is connected to the forced supply end determination unit 166. The second comparison unit 162 outputs the second comparison result information to the forced supply end determination unit 166.

  More specifically, when the density of the reference image is less than the second threshold value, the end of the forced toner supply process is determined. That is, this is a case where the density of the reference image does not increase even though the toner forcible supply processing has already been performed, and cannot be solved by the forced toner replenishment.

  In the present embodiment, the density level of the reference image is different between the first threshold value and the second threshold value. In other words, the density level of the reference image is set higher for the first threshold value than for the second threshold value. The density level is not limited to this, and the first threshold value and the second threshold value may be the same level.

  The forced supply end determination unit 166 is connected to the image formation execution control unit 150. The forced supply end determination unit 166 outputs an end instruction to the image formation execution control unit 150.

  By the way, when the developing unit 50 according to the present embodiment is shipped, the above-described seal members 122A and 122B are attached to the toner supply port 114 and the developer delivery port 120. At this time, if the user forgets to remove the seal member 122A, the toner density lowering phenomenon as described above occurs as printing is performed. Therefore, in the present embodiment, the print control management unit 88 is caused to detect forgetting to remove the seal.

  Here, when the first comparison result information input to the forced supply execution possibility determination unit 160 indicates that the density of the reference image is equal to or higher than the first threshold value, the forced toner supply process is not executed. decide. That is, the seal member presence / absence determination process is executed without executing the toner forced supply process.

  The forced supply execution availability determination unit 160 is connected to the third comparison unit 168. The forced supply execution determination unit 160 outputs a seal member presence / absence determination instruction to the third comparison unit 168.

  The third comparison unit 168 is connected to the third threshold value memory 170. The third comparison unit 168 compares the density information with a third threshold value stored in the third threshold value memory 170. The third comparison unit 168 is connected to the condition success / failure determination unit 172. The third comparison unit 168 outputs the third comparison result information to the condition success / failure determination unit 172.

  The condition success / failure determination unit 172 determines success / failure of the condition forgetting to remove the seal member based on the third comparison result information and other condition success / failure.

  More specifically, the condition success / failure determination unit 172 satisfies one of the conditions for forgetting to remove the seal member when the density of the reference image is less than the third threshold value. Next, the condition success / failure determination unit 172 determines the success or failure of other conditions for forgetting to remove the seal member. Other conditions for forgetting to remove the seal member include, for example, the number of print processes, the replenishment amount / pixel ratio, the image density, and the image forming conditions.

  Here, forgetting to remove the seal member 122A occurs when the new developing unit 50 starts to be used. Therefore, when the “number of printed sheets” exceeds a predetermined value (for example, 100 sheets), other causes As a result, the toner density is lowered. Accordingly, it is determined whether or not the number of print processed sheets is less than a specified value (condition is satisfied when the number is less than the specified value). In this case, not only the number of print processes but also the number of pixels (pixel count number) may be used as a condition.

  The “replenishment amount / pixel ratio” represents the ratio between the number of dispenses (the number of toner replenishments) and the pixel count number. Normally, the number of dispenses increases almost in proportion to the number of pixel counts, and a standard value of the ratio is stored in advance. In addition, since the ratio varies to some extent depending on the image forming apparatus 10 and usage conditions, a lower limit value and an upper limit value are also stored as limit values of the variation. For this reason, if the user forgets to remove the seal member 122A, even if a toner replenishment processing command is issued, the toner replenishment amount / pixel ratio is increased because the toner is not actually replenished. Therefore, it is determined whether or not the replenishment amount / pixel ratio is equal to or greater than the upper limit (the condition is satisfied when the upper limit is exceeded).

  Further, the “image density” is a pattern image density for image density different from the reference image density, and the density on the print is predicted by detecting this density, and image forming conditions for image density adjustment (for example, exposure) The image density is brought close to the target density by changing the amount and the developing bias. Therefore, it is determined whether the image density is less than the target density (the condition is satisfied when the image density is less than the target density).

  The “image forming condition” is determined by the upper limit value of the image forming condition such as the exposure amount and the developing bias. When the image density is less than the target value, the image forming condition is changed so that the image density approaches the target density. That is, since the image density also decreases as the toner density decreases due to forgetting to remove the seal member 122A, each image forming condition is changed to increase the image density. Therefore, it is determined whether or not the image forming condition is equal to or higher than the upper limit value (the condition is satisfied when the upper limit value is exceeded).

  The condition success / failure determination unit 172 is connected to the log analysis unit 152. The condition success / failure determination unit 172 determines success / failure of the other seal member forgetting to peel off conditions based on the log information. Note that the conditions for forgetting to remove the seal member may be that all of them are satisfied, or any one or some of them may be a condition.

  On the other hand, the condition success / failure determination unit 172 is connected to the image formation execution control unit 150. When the condition for forgetting to remove the seal member is not satisfied, information to that effect is output to the image formation execution control unit 150.

  In addition, the condition success / failure determination unit 172 is connected to the notification control unit 174. If the condition for forgetting to remove the seal member is satisfied, error information for forgetting to remove the seal member is output to the notification control unit 174. The notification control unit 174 is connected to the UI 82 and controls to notify the user of the error information using the UI 82.

  More specifically, in the present embodiment, if it is determined that the seal member is forgotten to be peeled off, the error is displayed on the UI 82 and a subsequent print instruction is not accepted. At the same time, the error information is recorded in the developing unit 50 and the toner cartridge.

  Further, since the error is restored to the normal state when the seal member 122A is originally removed, the error is restored by opening / closing the door for attaching / detaching the toner cartridge to / from the image forming apparatus 10 and turning the power switch off / on. It is like that.

  When the door is opened and closed and the power switch is turned on / off, the print control management unit 88 checks the error state of the developing unit 50. When the error information is recorded, first, toner is replenished according to the density of the formed toner density reference image. At this time, it is preferable not to shift to a later-described empty detection mode or forgetting to remove the seal member.

  Thereafter, after the developing unit 50 is idled for a predetermined time, the reference image is formed again and the density is detected. Here, a forced replenishment mode, an empty detection mode, a forgetting to remove the seal member detection mode, etc., which will be described later, are carried out in the same manner as usual.

  Therefore, after an error is displayed due to forgetting to remove the seal member 122A, if the user removes the seal member 122A, the necessary toner is supplied by the density measurement of the first reference image. When this is done, the mode forgetting to remove the seal member will not be entered. If the removal of the seal member 122A is neglected, the logic of the forgetting to remove the seal member mode is passed again and an error forgetting to remove the seal member is displayed.

  The operation of this embodiment will be described below.

(Image formation processing procedure)
First, an image forming procedure in the image forming apparatus 10 will be described.

  The charging roll 48 uniformly negatively charges the surface of the photosensitive drum 40 with a predetermined charging portion potential. Further, exposure is performed by the exposure device 62 so that the image portion on the charged photosensitive drum 40 has a predetermined exposure portion potential, and an electrostatic latent image is formed.

  That is, on the basis of image data supplied from the control unit 44, a latent image corresponding to an image is formed on each photoconductive drum 40 by turning on and off a semiconductor laser (not shown) and performing modulation.

  Further, when the electrostatic latent image on the rotating photosensitive drum 40 passes through the developing unit 50, the toner of the developer G stored in the developing unit 50 adheres to the electrostatic latent image by the developing bias, and the electrostatic latent image Is visualized as a toner image.

  Therefore, the paper P placed on the paper feed cassette 18 is sent out by the pickup roll 22 and further conveyed one by one by the paper feed roll 24 and the separation roll 26 that are rotationally driven. The paper P conveyed from the paper feed cassette 18 is temporarily stopped by the registration roller 28 and is sent between the photosensitive unit 30 and the transfer unit 32 at a predetermined timing. The paper P is held by the transport belt 66 and transported to the transfer unit 34 of each photoconductive drum 40, and the toner images on the photoconductive drum 40 are sequentially transferred to the paper P when passing through the transfer unit 34. .

  The toner image transferred to the paper P is fixed by the fixing device 36, and the paper P is discharged to the discharge tray 16 by the discharge roll 38.

(Forced replenishment mode, empty detection mode, forgetting to remove seal member detection mode)
Next, based on the flowcharts of FIGS. 5 to 7, a control routine incorporating a forced toner replenishment mode, a toner cartridge empty detection mode, and a seal member forgetting to peel off detection mode in the print control management unit 88 according to the present embodiment. Will be described. This routine is executed every time 25 pages (converted to JIS standard A4 size) are printed, and is started after measuring the reference image density for adjusting and controlling the toner density.

  In step 200, the forced supply counter A is reset (A ← 0). Next, the process proceeds to step 204 via step 202. Note that step 202 is a start of a loop in which steps 204 to 212 described later are repeated.

  In the next step 204, it is determined whether or not the forced supply counter A is less than a set value (for example, 3). If a negative determination is made (greater than or equal to the set value), the process proceeds to step 224 described later. On the other hand, when an affirmative determination is made (less than the set value), the routine proceeds to step 206.

  In step 206, it is determined whether or not the density of the reference image for toner density adjustment is lower than the toner forcible supply start level (first threshold value). That is, it is determined whether or not the density of the reference image is low to a level at which toner is forcibly supplied. If a negative determination is made (greater than or equal to the first threshold value), the process proceeds to step 242 described later. On the other hand, when an affirmative determination is made (less than the first threshold value), the routine proceeds to step 208.

  In step 208, it is determined whether or not the developing unit 50 is in a stable state. That is, when the number of printed sheets is small as in the initial state of the developing unit 50 (after installation of the image forming apparatus 10 or after replacement of the developing unit 50, etc.), the density of the reference image is detected low due to the influence of the developer lot or the like. This is to prevent the toner from being mistakenly recognized as having a low concentration and forcibly supplying toner. Specifically, the number of printed sheets of the developing unit 50 (a counter provided in the developing unit 50) may be used as a reference.

  If a negative determination is made in step 208 (less than the reference number), the process proceeds to step 210. In step 210, the sky detection flag G is turned off, and the routine proceeds to step 214.

  On the other hand, if an affirmative determination is made in step 208 (more than the reference number), the developing unit 50 is in a stable state, and the process proceeds to step 212. In step 212, the toner forcible replenishment flag F is turned on, and the routine proceeds to step 214.

  In the next step 214, the process returns to step 202, and steps 204 to 212 are repeated for each developing unit 50 (YMCK 4 colors). As a result, the forcible replenishment flag F of the developing unit 50 that requires forcible replenishment of toner is turned on.

  In the next step 216, it is determined whether or not the forcible replenishment flag F (step 212) is turned on even for one of the developing units 50 in the loop of step 202 to step 214 described above. If a negative determination is made (flag F is off), this routine ends. On the other hand, if an affirmative determination is made (at least one flag F is on), the process proceeds to step 218.

  In the next step 218, the forced supply counter A is incremented. Further, in step 220, a forced toner supply process is executed. In the next step 222, the reference image is formed again, the density sensor 91 detects the density of the reference image, and the process returns to step 202.

  On the other hand, when a negative determination is made in step 204 (the forced supply counter A is a set value (for example, 3) or more), the process proceeds to step 224. In other words, the toner forcible supply process is repeatedly executed, and the toner cartridge empty detection mode is set thereafter.

  In step 224, it is determined whether the forced supply flag F is on. If a negative determination is made (flag F is off), the process returns to step 214. On the other hand, if the determination is affirmative (flag F is on), the process proceeds to step 226. Since the process has already proceeded to step 224 via the forced supply mode, it can be said that the flag F is on and almost no negative determination is made. Therefore, this step 224 is a step for confirmation and can be omitted.

  In the next step 226, it is determined whether or not the density of the reference image for toner density adjustment is lower than the toner forcible supply end level (second threshold value). That is, it is determined whether or not the density of the reference image is low to a level at which forced toner supply is completed. If a negative determination is made (greater than or equal to the second threshold value), the process returns to step 210. On the other hand, if an affirmative determination is made (less than the second threshold value), the process proceeds to step 228. In this embodiment, the forcible supply end level (second threshold) is set to the forcible supply start level (first threshold value) so that an affirmative determination is made only when the toner density is reliably lowered. Although the density is set slightly lower than the threshold value, both levels may be set to the same level.

  In step 228, the value of the forced supply counter error is incremented. In the next step 230, it is determined whether or not the value of the forced supply counter error has reached the maximum value. If an affirmative determination is made in step 230 (maximum error value), the process proceeds to step 232.

  In step 232, it is determined whether or not the number of times the toner cartridge dispenser is driven exceeds a set value. If a negative determination is made (less than the set value), the process proceeds to step 234. That is, in this case, since there is a high possibility that another error has occurred, other error processing is executed, and this routine ends.

  On the other hand, when an affirmative determination is made at step 232 (below the set value), the routine proceeds to step 236. In step 236, toner cartridge empty detection display processing is executed, and the process proceeds to step 238.

  On the other hand, if a negative determination is made in step 230 (less than the maximum value), the process proceeds to step 240. In step 240, the value of the forced replenishment counter error is written in the memory, and the process proceeds to step 238.

  In step 238, the forcible supply flag F is turned off, and the process returns to step 214. In this case, since the flag F is turned off, this routine is ended depending on the relationship with the other developing units 50. Thereby, the forced supply mode ends.

  On the other hand, if a negative determination is made in step 206 (the density of the reference image for toner density adjustment is equal to or higher than the toner forcible supply start level (first threshold)), that is, no forced supply process is required. If yes, go to Step 242. That is, after that, the detection mode for forgetting to remove the seal member of the toner cartridge is set.

  In step 242, as one of the conditions for forgetting to remove the seal member, it is determined whether or not the number of print processed sheets is less than a specified value. If a negative determination is made (greater than a specified value), the process returns to step 210 because the condition is not satisfied. On the other hand, if an affirmative determination is made (less than the specified value), the process proceeds to step 246.

  In step 246, as one of the conditions for forgetting to remove the seal member, it is determined whether or not the density of the reference image for toner density adjustment is lower than the level for forgetting to remove the seal member (third threshold value). Here, in the present embodiment, for the density of the reference image, the level for forgetting to remove the seal is set to a level darker than the forcible supply start level. If a negative determination is made (greater than or equal to the third threshold value), the process returns to step 210 because the condition is not satisfied. On the other hand, when an affirmative determination is made (less than the third threshold value), the process proceeds to step 248.

  In step 248, as one of the conditions for forgetting to remove the seal member, it is determined whether the replenishment amount / pixel ratio is equal to or higher than the upper limit value. If a negative determination is made (less than the upper limit value), the process returns to step 212 because the condition is not satisfied. On the other hand, when an affirmative determination is made (over the upper limit value), the routine proceeds to step 250.

  In step 250, as one of the conditions for forgetting to remove the seal member, it is determined whether or not the image density is lower than the lower limit value. If a negative determination is made (more than the lower limit value), the process returns to step 212 because the condition is not satisfied. On the other hand, when an affirmative determination is made (less than the lower limit value), the routine proceeds to step 252.

  In step 252, as one of the conditions for forgetting to remove the seal member, it is determined whether the image forming conditions such as the exposure amount and the developing bias are equal to or higher than the upper limit value. If a negative determination is made (less than the upper limit value), the process returns to step 212 because the condition is not satisfied. On the other hand, when an affirmative determination is made (over the upper limit value), the routine proceeds to step 254. As a result, all the conditions for forgetting to remove the seal member are satisfied.

  In the next step 254, the forgetting to remove the seal member counter CS is incremented. Further, in step 256, it is determined whether or not the counter CS has reached the maximum value. If a negative determination is made (less than the maximum value), the process returns to step 210. On the other hand, if an affirmative determination is made (greater than the maximum value), the routine proceeds to step 258. In the next step 258, an error process for forgetting to remove the seal member is executed, and this routine ends.

  In this embodiment, the error process for forgetting to remove the seal member is executed after the detection mode for forgetting to remove the seal member is repeated. However, the present invention is not limited to this. Error processing may be executed by satisfying the forgetting condition.

  Although this routine is executed every time 25 pages are printed, the present invention is not limited to this, and the number of pages on which this routine is executed can be arbitrarily set, or may be set every predetermined date.

10 Image forming apparatus 50 Developing unit (developing apparatus)
88 Print Control Management Unit 91 Density Sensor 114 Toner Supply Port 122 Seal Member 150 Image Formation Execution Control Unit 152 Log Analysis Unit 154 Reference Image Density Reading Unit 156 First Comparison Unit 158 First Threshold Memory 160 Forced Supply Execution Availability Judgment unit (forced supply means)
162 Second comparison unit 164 Second threshold memory 166 Forced supply end determination unit 168 Third comparison unit 170 Third threshold memory 172 Condition success / failure determination unit (discrimination means)
174 Notification control unit

Claims (6)

Forcibly supplying means for monitoring the density of a reference image formed every predetermined image forming period and forcibly supplying toner via a toner supply port provided in the developing device, if necessary,
When the density of the reference image is higher than a first threshold that is a forced toner supply start level by the forced supply means, and when the processing amount of the developing device is less than a specified value, the forced toner monitors the concentration of the standard image in the third threshold darker than the first threshold value is a density of the reference image supply is required, the concentration of the reference image and the third A discriminating means for establishing a detection mode execution condition for discriminating at least the presence or absence of a seal member affixed to the toner supply port when less than a threshold value;
A seal member detection device having Toner provided forcibly in the developing device when the reference image is thin as a result of comparison with the first threshold value for the density of the reference image formed at each predetermined image forming period Comparison with a second threshold value, which is thinner than the first threshold value, for the density of the reference image formed after the toner is supplied through the supply port and the toner is forcibly supplied. As a result, when the reference image becomes thin, forced supply control means for stopping the forced supply of the toner,
The forced supply control unit executes when the density of the reference image is higher than the density of the first threshold, and is higher than the density of the reference image and the first threshold. The value is compared with a third threshold value, and when the reference density is less than the third threshold value, it is attached to the toner supply port mainly for preventing developer leakage during transportation. Determining means for establishing an execution condition of a detection mode for determining the presence or absence of the seal member provided;
A seal member detection device having   A seal member detection based on a comparison between the density of the reference image and a third threshold value is performed on the condition that the developing device is performing an image forming process equal to or less than a predetermined processing amount. Item 3. The seal member detection device according to Item 2. When the density of the reference image is lower than a third threshold value, the detection mode is as follows:
The first condition in which the ratio of the forced supply amount of toner to the image processing amount exceeds the upper limit, the second condition in which the image density becomes thinner than the lower limit value, and the set value of the image forming condition relating to the image forming process is higher than the upper limit value When at least one of the increasing third conditions is satisfied, or when all of the first condition, the second condition, and the third condition are satisfied, a seal member is attached to the toner supply port. The seal member detection device according to claim 2, wherein the seal member detection device is determined to be attached. The seal member detection device according to any one of claims 1 to 4,
A filling part filled with a two-component developer produced by toner and carrier at a predetermined ratio, and development for covering the filling part and sending the developer to the developer carrier based on the development process Development provided with a housing provided with the agent delivery port and the toner supply port, and a seal member affixed to each of the developer delivery port and the toner supply port mainly for preventing developer leakage during transportation An image forming apparatus applied as a detection means for forgetting to remove a seal member of an apparatus.   The sealing member detection program for functioning a computer as a sealing member detection apparatus of any one of Claims 1-4.

Images