JP2008233130A - Image forming apparatus and control method of the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To accurately calculate the storage amount of waste toner, while taking into consideration the abnormal situation, when abnormality such as jamming occurs in an image forming apparatus, and then avoiding overflow of the recovered toner, and to improve accuracy when informing a user of the toner-end. <P>SOLUTION: The image forming apparatus includes: an image memory 23 for storing image data to be an image forming object; a storage part 29 for storing the waste toner end amount of a part for recovering the waste toner from an intermediate transfer belt and the currently stored waste toner amount; and a control part 20 that calculates the recovered waste toner amount, while making the recovery amount of the waste toner associate with the image data of the image memory 23, after detecting the near end of the waste toner by the waste toner detecting sensor, and then, outputs a waste toner end signal, when the recovered waste toner amount reaches the waste toner end amount. When abnormalities, such as jamming occurs in the apparatus, the waste toner amount stored in the storage part 29 is processed by the control part 20, while considering the transfer to the sheet as not having performed at all. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an image forming apparatus and a method for controlling the image forming apparatus.

  Conventionally, with regard to the intermediate transfer waste toner storage unit, the near end of the intermediate transfer waste toner storage unit is detected by a transmission sensor due to reliable notification to the user, layout, and cost reduction restrictions. The number of pixels that form an image is counted, and the end detection is performed by predicting the amount contained in the intermediate transfer waste toner (for example, see Patent Document 1). Further, as such a related technique, an image forming apparatus capable of accurately measuring the amount of collected toner depending on whether the toner image formed on the photosensitive drum is transferred to a sheet or is left untransferred. Is disclosed (for example, see Patent Document 2). Furthermore, when replacing the toner cartridge, the toner collection amount per copy is calculated from the number of sheets copied by the previous cartridge and the number of jammings, and a toner full warning display is made based on the result. A technique for setting the number of copies to be performed is disclosed (for example, see Patent Document 3).

JP 2003-271023 A JP 2000-98825 A JP-A-9-90753

  However, in the conventional techniques as described above, the toner image is always transferred to the sheet and the amount of accommodation in the intermediate transfer waste toner is calculated. When all the toner images are collected in the intermediate transfer waste toner container due to an abnormality, a phenomenon that cannot be accurately predicted occurs, and waste toner overflows or toner end notification may not be performed accurately. There was a point.

  The present invention has been made in view of the above, and when an abnormality occurs in a jam or an image forming apparatus, the waste toner storage amount is accurately calculated in consideration of the situation, thereby preventing overflow of collected toner. One of the objects is to avoid the problem and improve the accuracy of the toner end notification.

  In order to solve the above-described problems and achieve the object, the invention according to claim 1 holds at least a superposition of the toner images of the respective colors formed through the developing device and the photoconductor, An intermediate transfer belt to be transferred, an intermediate transfer belt waste toner collecting unit for collecting waste toner on the intermediate transfer belt, a waste toner detection sensor for detecting an amount of waste toner in the intermediate transfer belt waste toner collecting unit, An image forming apparatus comprising: a toner density detecting unit configured to detect a density of a toner image formed on the intermediate transfer belt; and an image data storage unit that stores image data of an image forming target; and the intermediate transfer Waste toner amount storage means for storing the waste toner end amount of the belt waste toner recovery unit and the amount of waste toner currently stored, and waste toner by the waste toner detection sensor After detecting the end, the amount of waste toner collected is calculated in correspondence with the image data in the image data storage means, and when the amount of waste toner collected reaches the amount of waste toner end, a waste toner end signal is output. Waste toner end detection means for outputting, and the waste toner end detection means completely transfers the waste toner amount to the waste toner amount storage means to the paper when a jam or an abnormality occurs in the apparatus itself. It is characterized in that it is processed as not being performed.

  According to a second aspect of the present invention, there is provided an intermediate transfer belt that holds at least a superposition of toner images of respective colors formed via a developing device and a photoconductor, and transfers the toner image onto a sheet. An intermediate transfer belt waste toner collecting unit for collecting the waste toner, a waste toner detection sensor for detecting the amount of waste toner in the intermediate transfer belt waste toner collecting unit, and a density of the toner image formed on the intermediate transfer belt A method for controlling an image forming apparatus having toner density detecting means for detecting a jam, wherein a first step of detecting a jam or an abnormality of the image forming apparatus, and a jam or an abnormality detected in the first step A second step of calculating the amount of toner image on the intermediate transfer belt, a third step of calculating the amount of waste toner of the intermediate transfer waste toner collecting unit, A fourth step of detecting the waste toner end of the transfer the waste toner collection unit, characterized in that it comprises a.

  According to a third aspect of the present invention, the waste toner end detection means determines a toner image transferred to the paper and a toner image not transferred to the paper when an abnormality occurs in the jam or the image forming apparatus. In consideration of the case, the waste toner end detection of the intermediate transfer waste toner collecting unit is performed.

  The invention according to claim 4 further includes a step of determining a toner image transferred to the paper and an image not transferred to the paper, and whether or not to transfer to the paper when a jam or an abnormality occurs in the image forming apparatus. And a step of calculating the amount of waste toner of the intermediate transfer waste toner recovery unit, and controlling the image forming apparatus.

  According to a fifth aspect of the present invention, the waste toner end detection means stores a toner amount for each region in the moving direction for each toner image for the toner image on the intermediate transfer belt. When a jam or an abnormality occurs in the image forming apparatus during the transfer to the toner image, the waste toner end detection of the intermediate transfer waste toner collecting unit is performed in consideration of the toner amount and the paper position for each of the stored areas. And

  The invention according to claim 6 further includes a step of storing a toner amount for each region in the moving direction for each toner image, and when a jam or an abnormality occurs in the image forming apparatus while transferring the toner image to a sheet. And calculating the waste toner amount of the intermediate transfer waste toner recovery unit in consideration of the toner amount and paper position for each of the stored areas, and controlling the image forming apparatus.

  According to a seventh aspect of the invention, the waste toner end detection means calculates the amount of toner on the intermediate transfer belt in consideration of the rotational position of the photosensitive member when an abnormality occurs in the jam or the image forming apparatus. The waste toner end detection of the intermediate transfer waste toner recovery unit is performed.

  The invention according to claim 8 further includes a step of calculating the amount of toner on the intermediate transfer belt in consideration of the rotational position of the photosensitive member when a jam or an abnormality occurs in the image forming apparatus. The apparatus is controlled.

  According to a ninth aspect of the present invention, the waste toner end detection unit fails to adjust the voltage of the developing device using a sensor for detecting the toner density, and the toner adheres to the photoreceptor more than the normal range. If it is determined, the amount of toner stored in the intermediate transfer waste toner collecting unit is calculated to be large.

  The invention according to claim 10 further includes a step of adjusting the voltage of the developing device using a sensor for detecting the toner density, a step of determining that the toner is consumed more than a normal range, and a toner And a step of predicting a large amount of toner in the cartridge and a large amount of waste toner in the entire image forming apparatus, and controlling the image forming apparatus.

  In the invention according to claim 11, it is determined that the waste toner end detection unit has failed in the voltage adjustment of the developing device using the toner concentration detection unit, and the toner is consumed less than the normal range. In this case, the amount of toner stored in the intermediate transfer waste toner collecting unit is calculated to be small.

  The invention according to claim 12 further includes a step of adjusting the voltage of the developing device using the toner density detecting means, a step of determining that the toner is consumed less than the normal range, and an intermediate transfer And predicting a small amount of waste toner, and controlling the image forming apparatus.

  In the invention according to claim 13, when the waste toner end detection unit fails to adjust the voltage of the developing device using the toner concentration detection unit, the intermediate transfer waste toner recovery is performed in consideration of the difference from the normal range. The amount of toner contained in each part is calculated.

  The invention according to claim 14 further takes into account the difference between the step of performing voltage adjustment of the developing device using the toner density detecting means, the step of determining success / failure of voltage adjustment, and the normal range. And calculating the amount of intermediate transfer waste toner, and controlling the image forming apparatus.

  According to the present invention, when a toner image on the intermediate transfer belt is not transferred onto a sheet due to an abnormality in the jam or the image forming apparatus, the calculation of the waste toner storage amount for the toner image takes into account the transfer state to the sheet. Since the calculation is performed, it is possible to avoid the situation where the waste toner overflows from the intermediate transfer waste toner collection unit before the notification of the end of the intermediate transfer waste toner, and the notification accuracy can be improved.

  Exemplary embodiments of an image forming apparatus and a method for controlling the image forming apparatus according to the present invention are explained in detail below with reference to the accompanying drawings.

<Embodiment>
FIG. 1 is a schematic view showing an image forming apparatus to which the present invention is applied. In FIG. 1, the image forming process of the image forming apparatus is such that a charge is applied to the photoreceptors 1Y, 1C, 1M, and 1Bk to make them constant, and laser light is emitted from the LD device 12 to thereby apply the photoreceptor 1Y. 1C, 1M, and 1BK are partially exposed and neutralized, and the toner on the developing rollers 3Y, 3C, 3M, and 3Bk of the developing devices 2Y, 2C, 2M, and 2BK is moved to the formed electrostatic latent image, Toner image.

  In the case of a color image forming apparatus, an image forming unit (a set of a photosensitive member and a developing device) displays four toners: black toner (BK), yellow toner (Y), cyan toner (C), and magenta toner (M). The toner images are formed by arranging the four developing devices on one photoconductor or the like. The toner images formed on the photoconductors 1Y, 1C, 1M, and 1BK are transferred to the intermediate transfer belt 5 of the transfer device 4 that faces the photoconductors 1Y, 1C, 1M, and 1BK.

  The intermediate transfer belt 5 is stretched by a secondary transfer bias roller 6 that also serves as a support roller and a support roller 7, and can rotate counterclockwise in the illustrated example. When toner images are formed on the photoconductors (photoconductor drums) 1Y, 1C, 1M, and 1Bk, voltages are applied to the primary transfer rollers 8Y, 8C, 8M, and 8Bk corresponding to the respective colors. The toner images on 1C, 1M, and 1BK are sequentially transferred onto the intermediate transfer belt 5.

  A secondary transfer bias roller 6 also serving as a support roller is disposed inside the intermediate transfer belt 5, and is opposed to the secondary transfer unit 9 so as to face the opposite side of the intermediate transfer belt 5. is set up.

  Upstream of the secondary transfer unit, there is a registration roller pair 10 which is a part of the transfer paper transport device. The registration roller pair 10 holds the transfer paper sent from the paper supply device (the paper supply tray 15 and the paper supply roller 16), and waits until the transfer paper is ready for the transfer operation.

  The registration roller pair 10 is re-driven at a timing according to the toner image on the intermediate transfer belt 5, and the toner image formed by the secondary transfer unit 9 and the intermediate transfer belt 5 passes through the secondary transfer unit 9, Move to transfer paper. Downstream of the transfer device 4 is a fixing device 11 that also serves as a transport device. The transfer paper on which the toner image is thermally fixed by the fixing device 11 is discharged to the outside through a paper discharge roller (not shown).

  Reference numeral 13 denotes an intermediate transfer waste toner collecting unit that collects waste toner collected by the intermediate transfer belt cleaning device 18, and reference numeral 14 denotes an intermediate transfer waste toner detection sensor that detects the amount of waste toner in the intermediate transfer waste toner collecting unit 13. Reference numeral 15 is a paper feed tray for storing transfer paper, reference numeral 16 is a paper feed roller for producing the top sheet of the paper feed tray 15 one by one, and reference numeral 17 is a mark sensor for detecting a toner image on the intermediate transfer belt 5 (FIG. 3). Reference numeral 18 denotes an intermediate transfer belt cleaning device that collects residual toner on the intermediate transfer belt 5.

  As described above, the image forming apparatus includes four photoreceptors 1Y, 1C, 1M, and 1BK, the intermediate transfer belt 5 that is in contact with the photoreceptors 1Y, 1C, 1M, and 1BK, and lasers corresponding to image data on the photoreceptors of the respective colors. An LD device 12 for irradiating light, a mark sensor 17 for reading the density of the toner image on the intermediate transfer belt 5, an intermediate transfer belt cleaning device 18 and the like are arranged.

  FIG. 2 is a block diagram showing a configuration of a control system in the image forming apparatus of FIG. In this figure, the control unit 20 is constituted by a microcomputer system and controls the entire image forming apparatus in an integrated manner. The computer interface unit 21 communicates with a terminal that requests printing to the image forming apparatus. The plotter unit 22 creates a toner image from the image stored in the image memory unit 23 by an electrophotographic method, transfers it to a sheet, and discharges it outside the machine. The image memory unit 23 stores image data transmitted from a terminal that issues a print request to the image forming apparatus. The operation unit panel 24 displays the state of the image forming apparatus and receives input to the image forming apparatus. The print job management unit 25 manages the printing order for print jobs requested by the image forming apparatus. The mark sensor 17 detects the toner density on the intermediate transfer belt. A process control (process control) unit 27 adjusts the toner density by a developing bias. The storage unit 29 stores the current waste toner storage amount of the intermediate transfer waste toner recovery unit 13 and the waste toner end amount of the intermediate transfer waste toner recovery unit 13.

  The intermediate transfer waste toner recovery unit near end end detection unit 28 detects the waste toner near end by the intermediate transfer waste toner amount detection sensor 14, and after detecting the waste toner near end, the data in the image memory unit 23 is stored in the plotter unit 22. Each time the photosensitive members 1Y, 1C, 1M, and 1BK are exposed, the amount of waste toner stored in the intermediate transfer waste toner collecting unit 13 is calculated in consideration of the transfer efficiency to the sheet and added to the storage unit 29. When the value exceeds the waste toner end amount in the storage unit 29, the waste toner end is detected.

  FIG. 3 is an explanatory diagram showing the configuration of the mark sensor 17. The toner mark sensor 17 includes an LED light emitting unit 17a, a regular reflection light receiving unit 17b, and a diffuse reflection light receiving unit 17c. The light emitted from the LED light emitting unit 17a is applied to the intermediate transfer belt 5, and the reflected light is detected by the regular reflection light receiving unit 17b and converted into a voltage.

  The image forming apparatus forms a toner image in the plotter unit 22 and transfers the toner image onto the paper. However, the toner density transferred onto the paper varies due to deterioration of the parts and environmental (temperature / humidity) changes. Therefore, the toner concentration adjustment operation is executed in the process control unit 27 at the number of times of toner image creation and the timing of environmental change. As an example of the toner density adjustment operation, the charging bias to the photoconductors 1Y, 1C, 1M, and 1BK is kept constant, and exposure is performed from the LD device 12, respectively. At that time, the photoconductors are installed adjacent to the photoconductor. A toner image is formed by changing the developing bias of the toner cartridge. The formed toner image is read by the mark sensor 17.

  FIG. 4 shows the relationship between the developing bias and the mark sensor 17. The value of the mark sensor 17 can be converted into the toner density, and the smaller the voltage, the higher the toner density. In the toner density adjustment operation in the process control unit 27, the data shown in FIG. 4 is acquired, and the development bias that achieves the target toner density (target voltage in FIG. 4) of the image forming apparatus is calculated. The calculated development bias value is used in the plotter unit 22 to create a toner image having a stable density.

  Next, the waste toner near end and the waste toner end in the intermediate transfer waste toner storage unit 13 will be described. The near-end of the intermediate transfer waste toner storage unit 13 is performed by the intermediate transfer waste toner detection sensor 14. As an example of the detection method, there is a method in which a transmissive sensor is used as the intermediate transfer waste toner detection sensor 14 and the intermediate transfer waste toner near-end is detected when a blocking state for several consecutive seconds is detected. Regarding the waste toner end, since the sensor cannot be installed due to cost or layout restrictions, the determination is made based on the toner image formation amount after the near end is detected. As for the determination, assuming that toner image creation is performed with the target toner density, the control unit 20 predicts the toner storage amount of the intermediate transfer waste toner storage unit, and the intermediate transfer waste toner amount of the storage unit 29 In addition, the waste toner end amount in the storage unit 29 is compared, and if the waste toner end amount is exceeded, the waste toner end is displayed on the operation panel 24.

(End detection example 1)
The intermediate transfer waste toner collection unit near-end end detection unit 28 performs the following processing when image formation is performed by the plotter unit 22 in a state where the near-end is detected. Intermediate transfer waste toner collection unit Near-end end detection unit 28 collects the remaining toner amount obtained by multiplying the toner amount formed on the intermediate transfer belt 5 from the image data of the image memory unit 23 by the transfer efficiency to the sheet, and collects the intermediate transfer waste toner. The amount of waste toner stored in the unit 13 is stored in the storage unit 29 in association with the image data in the image memory unit 23. After that, the toner image formed on the intermediate transfer belt 5 corresponding to the image data in the image memory unit 23 is transferred to the paper at the timing when the transfer to the paper is completed. The waste toner amount corresponding to is added, and the waste toner amount data stored in association with the image data in the image memory unit 23 is deleted. In the above state, if the plotter unit 22 detects a jam (such as a paper jam at the transfer portion) or a system abnormality, all of the waste toner amount stored in association with the image data in the image memory unit 23 is stored. The transfer efficiency to the paper is 0%, that is, all the toner images formed on the intermediate transfer belt 5 to be transferred onto the transfer paper are recalculated as waste toner, and the waste toner capacity of the storage unit 29 is obtained. to add.

  FIG. 5 is a flowchart showing an operation procedure of the end detection example 1 according to the embodiment of the present invention. This operation is executed by the control unit 20 (see FIG. 2). In FIG. 5, it is first determined whether or not the intermediate transfer waste toner end state is reached (step S1). If it is determined that the intermediate transfer waste toner end state is reached, the image forming apparatus is further abnormal (jam or system error). Etc.) is not generated (step S2). If it is determined that no abnormality has occurred in the image forming apparatus, it is further determined whether or not the toner image has been transferred onto the paper (step S3). It is determined whether or not the image writing to the image has been completed (step S4). If it is determined that the image writing on the photosensitive member is completed, the amount of waste toner corresponding to the image data is calculated in consideration of the transfer to the paper (step S5). Subsequently, the amount of waste toner associated with the image data is stored in the storage unit 29 (step S6).

  On the other hand, if it is determined in step S3 that the toner image has been transferred to the paper, the waste toner corresponding to the transferred toner image is added to the waste toner storage amount in the storage unit 29 (step S7). Thereafter, it is determined whether or not waste toner storage amount> waste toner end amount (step S8). If it is determined that waste toner storage amount> waste toner end amount, intermediate transfer waste toner end detection is performed (step S8). S9). If it is determined in step S2 that an abnormality has occurred in the image forming apparatus, the amount of waste toner corresponding to the image data is recalculated without transfer to paper (step S10), and the waste toner is stored in the storage unit 29. The amount of waste toner corresponding to the image data is added to the amount (step S11), and the process proceeds to step S8.

  As described above, when the toner image on the intermediate transfer belt 5 is not transferred onto the paper due to a jam or an image forming apparatus, the calculation of the waste toner storage amount for the toner image is performed without performing the transfer to the paper. Therefore, it is possible to avoid a situation where the waste toner overflows from the intermediate transfer waste toner collection unit 13 before the intermediate transfer waste toner end notification.

(End detection example 2)
By the way, in the end detection example 1 described above, after a jam or an abnormality has occurred in the image forming apparatus, the toner image may be transferred to a sheet and discharged outside the machine. It is conceivable that the user may be notified of the toner storage unit end. Therefore, in this embodiment, when a jam or an abnormality occurs in the image forming apparatus, the intermediate transfer waste toner storage amount is calculated in consideration of the toner image transferred to the paper and the toner image not transferred to the paper.

  When a jam or system abnormality is detected by the plotter unit 22, the state of the toner image corresponding to the waste toner amount data stored in association with the image data in the image memory unit 23 is determined and is not transferred to the sheet. The transfer efficiency of only the toner image onto the paper is recalculated as 0%, and is added to the amount of waste toner stored in the storage unit 29.

  FIG. 6 is a flowchart showing an operation procedure of the end detection example 2 according to the embodiment of the present invention. This operation is executed by the control unit 20 (see FIG. 2). In this flowchart, the process of step S30 is different from the flowchart of FIG. 5 described above, and the other processes are the same. For this reason, the description about the overlapping part is omitted, and different operations will be described below.

  When it is determined in step S22 in FIG. 6 that an abnormality has occurred in the image forming apparatus, the amount of waste toner corresponding to the toner image not transferred to the paper is recalculated without transfer to the paper (step S30), and the storage unit 29 The amount of waste toner corresponding to the image data is added to the amount of waste toner stored in step S31 (step S31), and the process proceeds to step S28.

  As described above, when an abnormality occurs in the jam or the image forming apparatus, a toner image is normally transferred and a sheet that can be discharged outside the apparatus and a sheet that is discharged without transferring the toner image are generated. Since the calculation of the amount of waste toner is calculated for each development without performing transfer to the sheet and for performing transfer to the sheet, the accuracy of the intermediate transfer waste toner end notification can be improved.

(End detection example 3)
By the way, in the end detection example 2 described above, when a jam or an abnormality occurs in the image forming apparatus during the transfer of the toner image from the intermediate transfer belt 5 to the paper, the storage amount of the intermediate transfer waste toner storage portion depends on the position where the paper stops. May be different and predictions may be misaligned. Therefore, in this embodiment, the amount of accommodation in the intermediate transfer waste toner is calculated based on the toner image on the intermediate transfer belt and the position of the paper.

  When the plotter unit 22 detects a jam or system abnormality, it is determined that the toner image corresponding to the waste toner amount data stored in association with the image data in the image memory unit 23 is being transferred to the paper. Recalculates the amount of waste toner for each area of the toner image transferred to the paper and the area not transferred, and adds it to the amount of waste toner stored in the storage unit 29.

  FIG. 7 is a flowchart showing an operation procedure of the end detection example 3 according to the embodiment of the present invention. This operation is executed by the control unit 20 (see FIG. 2). In this flowchart, step S51 is different from the flowchart of FIG. 6 described above, and other processes are the same. For this reason, the description about the overlapping part is omitted, and different operations will be described below.

  In FIG. 7, the amount of waste toner corresponding to the toner image that is not transferred to the sheet is recalculated without transfer to the sheet (step S50), and the toner image that is being transferred to the sheet includes the area of the toner image transferred to the sheet. The amount of waste toner is recalculated for each area not transferred (step S51), and the amount of waste toner corresponding to the image data is added to the amount of waste toner stored in the storage unit 29 (step S52), and the process proceeds to step S48. .

  As described above, when an abnormality occurs in the jam or the image forming apparatus and the image forming apparatus stops during the toner image formation, the waste toner is accommodated in consideration of the toner amount transferred to the paper and the toner amount not transferred. Since the amount is calculated, the accuracy of the intermediate transfer waste toner end notification can be improved.

(End detection example 4)
By the way, in the end detection example 3 described above, when a jam or an abnormality occurs in the image forming apparatus during the toner image formation and the rotation of the photosensitive member stops, the number of pixels forming the toner image is counted, and the intermediate transfer waste If the amount of toner to be stored is predicted, the amount of toner stored in the photoreceptor waste toner storage unit installed adjacent to the photoreceptor cannot be predicted. Therefore, in this embodiment, the intermediate transfer waste toner storage amount is calculated in consideration of the stop position of the photosensitive member and the contact / separation state between the photosensitive member and the intermediate transfer belt.

  When a jam or system abnormality is detected by the plotter unit 22, if a toner image corresponding to the waste toner amount data stored in association with the image data in the image memory unit 23 is present on the photosensitive member, the toner image The amount of waste toner is set to 0 for the toner image that is not transferred to the intermediate transfer belt 5 by judging the state of the above.

  FIG. 8 is a flowchart showing an operation procedure of the end detection example 4 according to the embodiment of the present invention. This operation is executed by the control unit 20 (see FIG. 2). In this flowchart, step S72 is different from the flowchart of FIG. 7 described above, and other processes are the same. For this reason, the description about the overlapping part is omitted, and different operations will be described below.

  In FIG. 8, for the toner image being transferred to the paper, the amount of waste toner is recalculated for each area of the toner image transferred to the paper and not transferred (step S71), and then the toner image is on the photoreceptor. In this case, the state of the toner image is judged and the amount of waste toner is set to 0 for the toner image that is not transferred to the intermediate transfer belt (step S72). Then, the amount of waste toner corresponding to the image data is added to the amount of waste toner stored in the storage unit 29 (step S73), and the process proceeds to step S68.

  As described above, when an abnormality occurs in the jam or the image forming apparatus and the image forming apparatus stops during the toner image formation, the waste toner storage amount is calculated in consideration of the behavior of the toner image on the photosensitive member. In addition, the accuracy of the intermediate transfer waste toner end notification can be improved.

(End detection example 5)
By the way, in the end detection example 4 described above, the number of pixels forming the toner image is counted and the amount of the intermediate transfer waste toner is estimated, so that the voltage adjustment of the developing device fails and the voltage adjustment In the process of carrying out the procedure, the toner adhesion amount characteristic results in the waste toner storage being unpredictable if a jam or an image forming device malfunctions in a state where more toner is consumed than expected. There is a possibility that waste toner overflows. Therefore, in this embodiment, when the voltage adjustment of the developing device fails, the toner adhesion amount characteristic obtained in the process of voltage adjustment is consumed more than the assumed toner adhesion amount. If it is determined, the toner storage amount prediction is performed by adding a certain amount.

  In the toner density adjustment operation of the control unit 27, when the data of FIG. 4 is acquired and the data [3] is acquired, the developing bias is set to the bias when the previous toner density adjustment operation was successful, and the image forming operation Continue. In the above state, when a jam or an abnormality in the system is detected by the plotter unit 22, the waste toner storage amount calculation calculates the toner adhesion on the photosensitive member with the maximum value (the toner concentration at which the sensor voltage in FIG. 4 becomes 0V).

  FIG. 9 is a flowchart showing an operation procedure of the end detection example 5 according to the embodiment of the present invention. This operation is executed by the control unit 20 (see FIG. 2). This flowchart is different from the flowchart of FIG. For this reason, description of overlapping parts is omitted, and different operations will be described.

  If it is determined in step S83 in FIG. 9 that the transfer of the toner image to the paper has been completed, it is further determined whether or not the toner density adjustment operation has failed due to abnormally large toner adhesion (step S87). . If it is determined that the toner density adjustment operation has failed, the amount of waste toner stored in the storage unit 29 is recalculated with the toner image adhesion density being maximized (step S88), and the transferred toner image is handled. The waste toner is added to the amount of waste toner stored in the storage unit 29 (step S89). Thereafter, it is determined whether or not waste toner storage amount> waste toner end amount (step S90). If it is determined that waste toner storage amount> waste toner end amount, intermediate transfer waste toner end detection is performed (step S90). S91).

  If it is determined in step S82 that an abnormality has occurred in the image forming apparatus, the amount of waste toner corresponding to the toner image not transferred to the paper is recalculated without transfer to the paper (step S92), and the toner being transferred to the paper For the image, the amount of waste toner is recalculated for each area of the toner image transferred to the paper and for each area not transferred (step S94). Thereafter, it is determined whether the toner density adjustment operation has failed due to abnormally high toner adhesion (step S95). If it is determined that the toner density adjustment operation has failed, The amount of waste toner in the storage unit 29 is calculated with the maximum toner image adhesion density (step S96), and the amount of waste toner corresponding to the image data is added to the amount of waste toner stored in the storage unit 29 (step S97). move on.

  As described above, when a jam or an abnormality occurs in the image forming apparatus in a state where it is detected that more toner is consumed than the assumed toner consumption state by adjusting the bias of the developing device, the prediction of the toner storage amount is constant. By using the value obtained by adding the amount, the accuracy of the intermediate transfer waste toner end notification can be improved.

(End detection example 6)
By the way, in the above-described end detection example 5, when the exposure failure to the photoconductor occurs and the toner consumption is less than expected, the prediction of waste toner accommodation is deviated. Therefore, in this embodiment, the voltage adjustment of the developing device has failed, and the toner adhesion amount characteristic obtained in the process of performing the voltage adjustment consumes less than the assumed toner adhesion amount. If it is determined that there is, the toner storage amount prediction is performed by a value obtained by subtracting a certain amount.

  In the toner density adjustment operation of the control unit 27, when the data of FIG. 4 is acquired and the data [2] is acquired, the developing bias is set to the bias when the previous toner density adjustment operation was successful, and the image forming operation Continue. When the jam or system abnormality is detected by the plotter unit 22 in the above state, the waste toner storage amount calculation is performed with the minimum value (the toner density corresponding to the minimum sensor voltage in the acquired data).

  FIG. 10 is a flowchart showing an operation procedure of the end detection example 6 according to the embodiment of the present invention. This operation is executed by the control unit 20 (see FIG. 2). In this flowchart, steps S108 and S116 are different from the flowchart of FIG. 9 described above, and other processes are the same. For this reason, the description about the overlapping part is omitted, and different operations will be described below.

  If it is determined in step S107 that the toner density adjustment operation has failed, the amount of waste toner stored in the storage unit 29 is recalculated with the minimum toner image adhesion density (step S108). Further, in step S115 in FIG. 10, it is determined whether the toner density adjustment operation has failed due to abnormally large toner adhesion (step S115), and the toner density adjustment operation has failed. If it is determined, the amount of waste toner in the storage unit 29 is recalculated with the minimum value of the data obtained by adjusting the toner image adhesion density (step S116), and the amount of waste toner stored in the storage unit 29 corresponds to the image data. The amount of waste toner to be added is added (step S117), and the process proceeds to step S110.

  As described above, when it is detected that the toner consumption is less than the assumed toner consumption state by adjusting the bias of the developing device, the accuracy of the intermediate transfer waste toner end notification is obtained by performing the prediction of the toner storage amount by a value obtained by subtracting a certain amount. Can be improved.

(End detection example 7)
By the way, in the above-described end detection example, if the voltage adjustment of the developing device fails, the waste toner storage amount prediction is performed based on the assumption that normal toner consumption is performed, and thus an error occurs in the waste toner storage amount prediction. . Therefore, in this embodiment, when the voltage adjustment of the developing device fails, the toner storage amount of the intermediate transfer waste toner recovery unit is calculated in consideration of the difference from the normal range.

  In the toner density adjustment operation of the control unit 27, when the data of FIG. 4 is acquired and the data [3] is acquired, the developing bias is set to the lower limit value, and the waste toner capacity calculation corresponds to the developing bias lower limit value. This is carried out according to the toner consumption. FIG. 12 is a flowchart showing an operation procedure in this case.

  FIG. 11 is a flowchart showing an operation procedure of the end detection example 7 according to the embodiment of the present invention. This operation is executed by the control unit 20 (see FIG. 2). In this flowchart, steps S128 and S136 are different from the flowchart of FIG. 10 described above, and other processes are the same. For this reason, the description about the overlapping part is omitted, and different operations will be described below.

  If it is determined in step S127 in FIG. 11 that the toner density adjustment operation has failed, the amount of waste toner in the storage unit 29 is set to a lower limit of the normal range from the data obtained by the toner image adhesion density adjustment operation. The toner adhesion amount at the time of bias is recalculated (step S128). If it is determined in step S135 in FIG. 11 that the toner density adjustment operation has failed, the amount of waste toner stored in the storage unit 29 is within a normal range from the data obtained by the toner image adhesion density adjustment operation. The toner adhesion amount at the lower limit bias is recalculated (step S136), the waste toner amount corresponding to the image data is added to the waste toner storage amount in the storage unit 29 (step S137), and the process proceeds to step S130.

  As described above, when an abnormality is detected in toner consumption by adjusting the voltage of the developing device, the toner transfer amount of the intermediate transfer waste toner recovery unit is calculated in consideration of the difference between the abnormal value and the normal range, thereby performing intermediate transfer. The accuracy of waste toner end notification can be improved.

  As described above, the image forming apparatus and the image forming apparatus control method according to the present invention are useful for an image forming apparatus such as a color copying machine or a laser printer, and in particular, waste toner on an image carrier after transfer. It is suitable for an apparatus, a method, and a system for calculating the amount of waste toner in consideration of the state of the apparatus at the time of storage and detecting an accurate waste toner end.

1 is a schematic diagram illustrating an image forming apparatus to which the present invention is applied. FIG. 2 is a block diagram illustrating a configuration of a control system in the image forming apparatus of FIG. 1. It is explanatory drawing which shows the structure of a mark sensor. It is a graph which shows the relationship between a development bias and a mark sensor. It is a flowchart which shows the operation | movement procedure of the end detection example 1 concerning embodiment of this invention. It is a flowchart which shows the operation | movement procedure of the end detection example 2 concerning embodiment of this invention. It is a flowchart which shows the operation | movement procedure of the end detection example 3 concerning embodiment of this invention. It is a flowchart which shows the operation | movement procedure of the end detection example 4 concerning embodiment of this invention. It is a flowchart which shows the operation | movement procedure of the end detection example 5 concerning embodiment of this invention. It is a flowchart which shows the operation | movement procedure of the end detection example 6 concerning embodiment of this invention. It is a flowchart which shows the operation | movement procedure of the end detection example 7 concerning embodiment of this invention.

Explanation of symbols

1Y, 1C, 1M, 1BK Photoconductor 2Y, 2C, 2M, 2BK Developing device 4 Transfer device 5 Intermediate transfer belt 13 Intermediate waste toner recovery unit 14 Intermediate transfer waste toner detection sensor 17 Toner mark sensor 18 Intermediate transfer belt cleaning device 20 Control Unit 22 plotter unit 23 image memory 27 process control unit 28 intermediate transfer waste toner recovery unit near end / end detection unit 29 storage unit

Claims (14)

An intermediate transfer belt that holds at least a superimposed toner image of each color formed through a developing device and a photoconductor and transfers it to a sheet, and an intermediate transfer belt waste that collects waste toner on the intermediate transfer belt A toner collection unit, a waste toner detection sensor that detects the amount of waste toner in the intermediate transfer belt waste toner collection unit, and a toner concentration detection unit that detects the density of a toner image formed on the intermediate transfer belt. An image forming apparatus having
Image data storage means for storing image data to be imaged;
Waste toner amount storage means for storing a waste toner end amount of the intermediate transfer belt waste toner collecting unit and a currently stored waste toner amount;
After detecting the waste toner near-end by the waste toner detection sensor, the amount of waste toner collected is calculated corresponding to the image data in the image data storage means, and the amount of waste toner collected reaches the waste toner end amount. Waste toner end detection means for outputting a waste toner end signal when
With
The waste toner end detection means processes the amount of waste toner stored in the waste toner amount storage means as not being transferred to the paper at all when a jam or an abnormality occurs in the apparatus. Image forming apparatus. An intermediate transfer belt that holds at least a superimposed toner image of each color formed through a developing device and a photoconductor and transfers it to a sheet, and an intermediate transfer belt waste that collects waste toner on the intermediate transfer belt A toner collection unit, a waste toner detection sensor that detects the amount of waste toner in the intermediate transfer belt waste toner collection unit, and a toner concentration detection unit that detects the density of a toner image formed on the intermediate transfer belt. An image forming apparatus control method comprising:
A first step of detecting a jam or an abnormality in the image forming apparatus;
A second step of calculating the amount of toner image on the intermediate transfer belt when a jam or abnormality is detected in the first step;
A third step of calculating a waste toner amount of the intermediate transfer waste toner collecting unit;
A fourth step of detecting a waste toner end in the intermediate transfer waste toner collecting section;
A control method for an image forming apparatus.   The waste toner end detection means judges a toner image transferred to the paper and a toner image not transferred to the paper when a jam or an abnormality occurs in the image forming apparatus, and collects the intermediate transfer waste toner in consideration of each case. The image forming apparatus according to claim 1, wherein waste toner end detection of a part is performed. further,
Determining a toner image transferred to paper and an image not transferred to paper when an error occurs in a jam or an image forming apparatus;
Calculating the amount of waste toner in the intermediate transfer waste toner recovery unit in consideration of whether or not to transfer to paper;
The method for controlling an image forming apparatus according to claim 2, further comprising: controlling the image forming apparatus.   The waste toner end detection means stores a toner amount for each area in the moving direction for each toner image on the intermediate transfer belt, and stores the toner amount in a jam or an image forming apparatus while transferring the toner image to a sheet. 4. The image formation according to claim 3, wherein when an abnormality occurs, waste toner end detection of the intermediate transfer waste toner recovery unit is performed in consideration of a toner amount and a paper position for each of the stored areas. apparatus. further,
Storing a toner amount for each region in the moving direction for each toner image;
If a jam or an error occurs in the image forming device while transferring the toner image to the paper, the amount of waste toner in the intermediate transfer waste toner recovery unit is calculated in consideration of the amount of toner stored in each area and the paper position. And steps to
The method of controlling an image forming apparatus according to claim 4, further comprising: controlling the image forming apparatus.   The waste toner end detection means calculates the amount of toner on the intermediate transfer belt in consideration of the rotational position of the photoconductor when an abnormality occurs in the jam or the image forming apparatus, and waste toner in the intermediate transfer waste toner recovery unit The image forming apparatus according to claim 5, wherein end detection is performed.   And a step of calculating an amount of toner on the intermediate transfer belt in consideration of a rotational position of the photosensitive member when an abnormality occurs in the jam or the image forming apparatus, and the image forming apparatus is controlled. Item 7. A method for controlling an image forming apparatus according to Item 6.   If the waste toner end detection unit fails to adjust the voltage of the developing device using the sensor for detecting the toner density and it is determined that the toner adheres to the photoreceptor more than the normal range, the intermediate transfer waste toner The image forming apparatus according to claim 7, wherein a large amount of toner is stored in the collecting unit. further,
Performing voltage adjustment of the developing device using a sensor for detecting toner density;
Determining that more toner is consumed than in the normal range;
Predicting a large amount of toner in the toner cartridge and waste toner in the entire image forming apparatus;
The method of controlling an image forming apparatus according to claim 8, further comprising: controlling the image forming apparatus.   When the waste toner end detection unit fails to adjust the voltage of the developing device using the toner concentration detection unit and it is determined that less toner is consumed than the normal range, the toner in the intermediate transfer waste toner recovery unit The image forming apparatus according to claim 7, wherein the amount of storage is calculated to be small. further,
Performing voltage adjustment of the developing device using the toner density detecting means;
Determining that toner is consumed less than the normal range;
Predicting less intermediate transfer waste toner capacity;
The method of controlling an image forming apparatus according to claim 8, further comprising: controlling the image forming apparatus.   The waste toner end detection unit calculates a toner storage amount of the intermediate transfer waste toner recovery unit in consideration of a difference from a normal range when voltage adjustment of the developing device using the toner concentration detection unit fails. The image forming apparatus according to claim 7. further,
Performing voltage adjustment of the developing device using the toner density detecting means;
Determining the success / failure of the voltage adjustment;
A step of calculating the intermediate transfer waste toner amount in consideration of the difference from the normal range;
The method of controlling an image forming apparatus according to claim 8, further comprising: controlling the image forming apparatus.

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