JP2012155148A - Image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming apparatus in which when a storage detector for measuring the magnetic permeability of toner and magnetic carrier stored in a container, to detect that the storage amounts of the toner and the carrier are a set amount or more is adopted, the detection by the storage detector can be surely performed, even when a toner discharge operation for forming a toner image not transferred to a medium to be recorded on a photoreceptor is performed and the toner image not transferred to the medium to be recorded is removed by a cleaning device for the photoreceptor and then, stored in the container, so that the ratio of the toner in the container is higher than the ratio of the magnetic carrier in the container, compared with when the toner discharge operation is not performed and it happens that the detection by the storage detector is difficult.SOLUTION: The part where the measurement of the magnetic permeability by the storage detector is valid, of the container is set as a virtual region where the necessity of the detection by the storage detector is confirmed and control means determines whether or not the next executed image formation operation is an image formation operation for the toner discharge operation in a step where the storage amount in the container reaches the virtual region and performs prediction detection for predicting and detecting that the storage amount is the set amount or more, based on accumulation information on the supply time of a supply device, etc., when the next executed image formation operation is the image formation operation for the toner discharge operation.

Description

  The present invention relates to an image forming apparatus.

  As an image forming apparatus such as a copying machine or a printer that forms an image composed of a developer, for example, an image forming apparatus that forms an image by developing with a magnetic developer and the image forming apparatus are not required. There is known a developer recovery system that collects developer in a container and detects with a magnetic sensor that the accumulated amount of developer collected and accumulated in the container has reached a predetermined level. (Patent Document 1).

  Patent Document 1 exemplifies a two-component developer composed of a non-magnetic toner and a magnetic carrier and a magnetic one-component developer (toner) as a magnetic developer. In addition, as a developer that becomes unnecessary in the image forming device and is collected in the developer recovery system, a deteriorated developer that is not used for development in the image forming device and deteriorates and becomes unnecessary, or remains after use in the image forming device. For example, residual toner that is removed by cleaning is unnecessary.

  Further, in a printing apparatus having means for displaying the amount of waste toner collected in the waste toner container, means for counting the number of pixels of the original image in units of print pages, means for accumulating the counted number of pixels, Means for presetting the number of pixels when the toner container is full of waste toner, and means for calculating the amount of accumulated toner and the amount of toner collected in the waste toner container based on the set number of pixels, There is known a printing apparatus that determines whether or not the cumulative number of accumulated pixels exceeds the total number of pixels that is assumed to be full, and stops the print engine when the number is exceeded (Patent Document 2).

  In Patent Document 2, as a means for correcting the counted number of pixels, a means for correcting by the transfer rate of toner to a transfer material, or a predetermined number of pixels is added to the counted number of pixels every time a print job is completed. It is shown to comprise means. Further, according to this image forming apparatus, it is possible to accurately detect when the waste toner is full in the waste toner container in view of the fact that the light transmission type sensor cannot accurately detect the full state of the waste toner. It is shown.

  In recent years, in such an image forming apparatus, a special developer (toner) image that is not transferred to a recording medium such as recording paper is formed on a photosensitive member, and a certain amount of developer (toner) in the developing apparatus is provided. There is one that performs the operation of discharging the quantities together. This toner release operation is performed, for example, in order to restore (maintain) the quality of the image by eliminating a factor that causes a reduction in the quality of the image by executing the toner release operation accompanied by the formation of the special toner image. There are many cases.

  Specifically, for example, among the developers contained in the developing device, there is a developer that is not subjected to the development process and stays in the developing device and deteriorates in characteristics. Due to the presence, good development may not be achieved, and as a result, the image quality may be degraded. For this reason, a special toner image is formed on the photoconductor so that a part of the developer including the developer having deteriorated characteristics is discharged to the outside of the developing device, and a new developer is replaced with the released developer. A part of the developer is replaced by replenishing. The deterioration of the developer at this time is, for example, that an external additive such as a charge adjusting agent is detached from the toner particles, or is buried in the toner particles to deteriorate the characteristics required for the toner. It is.

  In addition to this, for example, a discharge product generated in the charging process is present on the surface of the photoconductor, thereby deteriorating the characteristics of the photoconductor, and an image flow formed by shifting a part of the charge of the latent image. Image defects may occur. Therefore, a special toner image is formed on the surface of the photoconductor and sent to a photoconductor cleaning device, and the discharge product is removed together with the toner image by the cleaning device.

JP 2001-209286 A Japanese Patent Laying-Open No. 2005-241676

  This invention collects and stores the toner and magnetic carrier constituting the developer, and measures the magnetic permeability of the toner and magnetic carrier contained in the container to set the amount of toner and magnetic carrier contained in the container. In the case of using a storage detector that detects that the amount exceeds the limit, a toner discharge operation is performed to form a toner image that is not transferred onto the recording medium on the photoconductor, and the toner image that is not transferred is removed by the photoconductor cleaning device. By being stored in the container after being removed, the ratio of the toner in the container is higher than the ratio of the magnetic carrier compared to the case where the toner releasing operation is not performed, and detection by the storage detector becomes difficult. Even if there is an image, it is possible to reliably detect the capacity of the container and to avoid the overflow of the developer from the container and the occurrence of clogging of the developer in the collecting and conveying device. There is provided a forming apparatus.

The image forming apparatus of the present invention (A1)
A photoreceptor,
A charging device for charging the surface of the photoreceptor;
An exposure apparatus that irradiates light onto the charged surface of the photoconductor to form a latent image;
A developing device that develops the latent image formed on the photoreceptor with a developer containing toner and a magnetic carrier to form a toner image, and a part of the developer is discharged;
A transfer device for finally transferring the toner image formed on the photoreceptor to a recording medium;
A cleaning device that removes at least toner remaining on the surface of the photoreceptor after transfer;
A replenishing device for replenishing the developing device with toner and magnetic carrier constituting the developer;
A container containing at least the toner removed by the developer discharged from the developing device and the cleaning device;
A collecting and conveying device that connects between the developing device and the cleaning device and the container, collects the toner and the magnetic carrier, and conveys the toner and the magnetic carrier to the container;
A storage detector for measuring the magnetic permeability of the magnetic carrier stored in the container and detecting that the storage amount of the toner and the magnetic carrier in the container is equal to or greater than a set amount;
Control means for executing a toner discharge operation for forming a special toner image not transferred to the recording medium on the photosensitive member;
Have
A portion where the measurement of the permeability of the storage detector is effective among the containers is set as a virtual region for confirming the necessity of detection by the storage detector,
The control means determines whether an image forming operation to be executed next when the amount of toner and magnetic carrier stored in the container reaches the virtual region is an image forming operation related to the toner releasing operation. In the case where it is determined that the image forming operation is related to the toner discharge operation, the amount of storage is determined based on the replenishment time of the replenishing device or the accumulated information of the number of pixels of the latent image instead of the detection by the storage detector. Predictive detection is performed to predict and detect that has exceeded the set amount.

The image forming apparatus of the invention (A2) is the image forming apparatus of the invention A1,
A plurality of the containers are installed, and a switching mechanism is provided in the collecting and transporting device to transport the toner and the magnetic carrier to any of the plurality of containers and switch the storage destination.
In the stage where the amount of toner and magnetic carrier accommodated in any of the plurality of containers reaches the virtual area, the control means includes the presence or absence of another container and the capacity of the other container is equal to or greater than the virtual area. If the other container is present and it is determined that the amount stored in the other container is less than the virtual area, the storage destination in the switching mechanism is determined. It is to switch to the container.

The image forming apparatus of the invention (A3) is the image forming apparatus of the invention A2,
When the control means determines that there is no other container in the determination or other container is present and the amount of the other container is greater than or equal to the virtual region,
When it is determined that an image forming operation to be executed next is an image forming operation related to the toner discharge operation, the storage destination in the switching mechanism is switched to a container in which the storage amount reaches the virtual region and the prediction detection is performed. Is to do.

The image forming apparatus according to the invention (A4) is the image forming apparatus according to any one of the inventions A1 to A3.
The control means predicts and determines whether or not the accommodation amount has reached the virtual area based on the replenishment time or the cumulative information of the number of pixels.

The image forming apparatus according to the invention (A5) is the image forming apparatus according to any one of the inventions A1 to A4.
When the image forming operation related to the toner discharge operation is executed, the control unit performs a correction process for increasing the accumulated information of the replenishment time or the number of pixels, and based on the accumulated information after the correction process is performed. The prediction detection is performed.

The image forming apparatus of the present invention (B1)
A photoreceptor,
A charging device for charging the surface of the photoreceptor;
An exposure apparatus that irradiates light onto the charged surface of the photoconductor to form a latent image;
A developing device that develops the latent image formed on the photoreceptor with a developer containing toner and a magnetic carrier to form a toner image, and a part of the developer is discharged;
A transfer device for finally transferring the toner image formed on the photoreceptor to a recording medium;
A cleaning device that removes at least toner remaining on the surface of the photoreceptor after transfer;
A replenishing device for replenishing the developing device with toner and magnetic carrier constituting the developer;
A plurality of containers containing the developer discharged from the developing device and at least the toner removed by the cleaning device;
A collecting and conveying device that connects between the developing device and the cleaning device and the plurality of containers, collects the toner and the magnetic carrier, and conveys them to the containers;
A switching mechanism that is provided in the collecting and transporting device and transports the toner and the magnetic carrier to any of the plurality of containers to switch the accommodation destination;
A storage detector that measures the magnetic permeability of the toner and magnetic carrier stored in the container and detects that the storage amount of the toner and magnetic carrier in the container is equal to or greater than a set amount;
Control means for performing a toner discharge operation for forming a toner image not transferred to the recording medium on the photosensitive member;
Have
The control means determines whether or not an image forming operation to be executed next is an image forming operation related to the toner discharging operation, and if it is determined that the image forming operation is related to the toner discharging operation, the switching is performed. When the transport destination of the mechanism is switched to a dedicated container selected in advance from among the plurality of containers, and when it is determined that the image forming operation is not related to the toner discharge operation, the transport destination of the switching mechanism is changed to the dedicated container. Switch to a container other than
In addition, for the dedicated container, predictive detection is performed to predict and detect that the storage amount is equal to or greater than a set amount based on the replenishment time of the replenishing device or the accumulated information of the number of pixels of the latent image. is there.

  According to the image forming apparatus of the invention A1, the container for collecting and storing the toner and the magnetic carrier constituting the developer, and the toner in the container by measuring the magnetic permeability of the toner and the magnetic carrier stored in the container When a storage detector that detects that the storage amount of the magnetic carrier is equal to or greater than the set amount is employed, a toner discharge operation is performed to form a toner image that is not transferred onto the recording medium on the photosensitive member, and the toner image that is not transferred Is removed by the photoconductor cleaning device and stored in the container, so that the toner ratio in the container is higher than the magnetic carrier ratio compared with the case where the toner releasing operation is not performed. Even if it is difficult to detect the developer, the container capacity is reliably detected to prevent the developer from overflowing from the container or clogging of the developer in the collecting and conveying device. It is possible to avoid.

  In the image forming apparatus according to the invention A2, the opportunity to detect the storage amount of the container whose storage amount has reached the virtual region by detection by the storage detector is increased as compared with the case where the configuration is not provided. It is possible to more reliably detect the storage amount, and to easily avoid the overflow of the developer from the container and the clogging of the developer in the collecting and conveying apparatus. In addition, it is possible to prevent the effective use of the container from being hindered by an error in prediction detection.

  In the image forming apparatus according to the invention A3, even when the accommodation destination cannot be switched to another container as compared with the case where the image forming apparatus does not have the configuration, the respective container amounts of the plurality of containers are more reliably detected. Thus, the overflow of the developer from the container and the clogging of the developer in the collecting and conveying apparatus can be easily avoided.

  In the image forming apparatus according to the invention A4, as compared with the case where the image forming apparatus does not have the configuration, it is possible to more reliably detect the amount of the container before the amount of the container reaches the virtual region. Occurrence of clogging of the developer in the collecting and conveying device can be avoided more reliably.

  In the image forming apparatus according to the invention A5, even when the image forming operation related to the toner releasing operation is executed and the predictive detection is performed, the container storage amount is more reliably detected than in the case where the image forming apparatus does not have the configuration. Therefore, it is possible to more reliably avoid the overflow of the developer from the container and the clogging of the developer in the collecting and conveying apparatus.

  According to the image forming apparatus of the invention B1, as compared with the case where the configuration is not provided, the container for collecting and storing the toner and the magnetic carrier constituting the developer, and the magnetic permeability of the magnetic carrier stored in the container Toner discharge operation to form a special toner image that is not transferred to the recording medium on the photosensitive member when a storage detector that detects that the storage amount of the toner and the magnetic carrier in the container exceeds the set amount is measured. The special toner image is removed by the photoconductor cleaning device, transported to the container, and stored in the container, so that the toner ratio increases rapidly compared to the magnetic carrier ratio and is detected by the storage detector. However, it is possible to reliably detect the capacity of the container to prevent the overflow of the developer from the container and the clogging of the developer in the collecting and conveying device. Kill.

1 is an explanatory diagram showing an overview of an image forming apparatus according to Embodiment 1. FIG. FIG. 2 is an explanatory diagram conceptually showing a part (image forming apparatus and developer supply system) in the image forming apparatus of FIG. 1. FIG. 2 is a partial cross-sectional explanatory diagram illustrating a configuration of a collection system for toner, a carrier, and the like provided in the image forming apparatus of FIG. 1. It is sectional drawing which expands and shows a part of conveying apparatus in the collection | recovery system of FIG. It is explanatory drawing which shows the structure of the container used by the collection | recovery system of FIG. 3, an accommodation detection sensor, etc. FIG. It is explanatory drawing which shows the structure of the external shape of the container of FIG. FIG. 6 is an explanatory diagram illustrating a formation position and the like of a special toner image in a toner discharge operation. It is a graph which shows the result of having measured the relationship with the output of the accommodation detection sensor with respect to the toner density | concentration in a container. FIG. 3 is an explanatory diagram illustrating a configuration related to main control in the image forming apparatus. It is a flowchart which shows the process process of the confirmation operation | movement of the storage capacity state of a container. It is a flowchart which shows the process process of the collection | recovery operation | movement of a collection | recovery system, and the detection operation of the storage capacity of a container. It is a flowchart which shows the process process of count operation | movement of the accumulation information used for prediction detection, and its determination operation | movement. 6 is a flowchart illustrating processing steps of a recovery operation of a recovery system and a detection operation of a container capacity in an image forming apparatus according to a second embodiment. 10 is a flowchart illustrating processing steps of a recovery operation of the recovery system and a detection operation of a container capacity in the image forming apparatus according to the third embodiment.

[Embodiment 1]
FIG. 1 shows an outline of an image forming apparatus 1 according to the first embodiment, FIG. 2 shows a part of the image forming apparatus 1 (image forming apparatus and developer supply system), and FIG. 3 shows the image forming apparatus 1. The other part (recovery system) in is shown.

  The image forming apparatus 1 is configured as a color printer, for example. In the image forming apparatus 1, a toner (coloring or the like) that forms a developer in an internal space of the housing 10 based on information of an input image using an image recording method such as a known electrophotographic method or electrostatic recording method. A plurality of image forming devices 20 that form toner images developed with fine powder), and a recording sheet 9 as an example of a recording material that holds the toner images formed by the image forming device 20 and finally The intermediate transfer device 30 for transferring, the paper feeding device 40 for accommodating and transporting the required recording paper 9 to be supplied to the secondary transfer position of the intermediate transfer device 30, and the recording with the toner image transferred by the intermediate transfer device 30 A fixing device 45 that fixes the toner image through the paper 9, a collection system 100 that collects unnecessary developer in the image forming device 20 and the intermediate transfer device 30, a control device 7, and the like are installed. The housing 10 has a support structure portion and an exterior portion formed of a support member, an exterior cover, and the like. An alternate long and short dash line in the figure indicates a conveyance path through which the recording paper 9 is mainly conveyed in the housing 10.

  The image forming apparatus 20 exclusively forms four color toner images of yellow (Y), magenta (M), cyan (C), and black (black: K) and special color toner images of special colors SA and SB. It is composed of six image forming devices 20Y, 20M, 20C, 20K, 20SA, and 20SB. The six image forming devices 20 (Y, M, C, K, SA, and SB) are arranged so as to be arranged in series in the internal space of the housing 10. Each image forming device 20 (Y, M, C, K, SA, SB) has a substantially common configuration as described below.

  Each image forming device 20 (Y, M, C, K, SA, SB) includes a rotating photosensitive drum 21 as shown in FIG. 1 and FIG. Such devices are mainly arranged. The main devices are a charging device 22 for charging the surface of the photosensitive drum 21 (image holding surface capable of charging and forming a latent image) to a required potential, and an image on the charged surface of the photosensitive drum 21. An exposure device 23 that irradiates light based on information (signal) to form an electrostatic latent image (for each color) having a potential difference, and the corresponding color (Y, M, C, K, SA) , SB) and developing device 24 (Y, M, C, K, SA, SB) that develops the toner image as a visible image by developing with the developer toner, and intermediate transfer device 30 (intermediate of the toner image). A primary transfer device 25 that transfers to a transfer belt), and a drum cleaning device 26 that removes deposits such as toner remaining on the image holding surface of the photosensitive drum 21 after transfer.

  The photosensitive drum 21 is formed by forming an image holding surface having a photoconductive layer (photosensitive layer) made of a photosensitive material on the peripheral surface of a cylindrical or columnar base material to be grounded. FIG. 8: Receiving power from the rotation drive unit 16A), it rotates in the direction indicated by the arrow. The charging device 22 is a contact-type charging device that is disposed in contact with the surface of the photosensitive drum 21 and includes a contact member such as a charging roll to which a charging bias is supplied. As the charging bias, when the developing device 24 performs reverse development, a voltage or current having the same polarity as the charging polarity of the toner supplied from the developing device is supplied from the charging power source 16B (FIG. 9).

  The exposure device 23 irradiates light (dotted line with arrows) configured according to image information input to the image forming apparatus 1 onto the image holding surface of the photosensitive drum 21 after being charged, and electrostatically It forms a latent image. As the exposure device 23, a scanning type configured using optical components such as a semiconductor laser and a polygon mirror is used, but in addition, for example, configured using a light emitting diode and an optical component. A non-scanning exposure apparatus may be used. In the exposure device 23, image processing necessary for the image processing device 27 is performed on the information of the image to be printed input to the image forming apparatus 1, and the image signal of each color component obtained after the processing is exposed to the exposure drive unit. 16C (FIG. 9). An image information apparatus (not shown) such as an image reading apparatus, an information terminal such as a personal computer, or a storage medium read / write apparatus can be connected to the image forming apparatus 1 via the connection communication unit 12. Image information is input from the device.

  The developing device 24 (Y, M, C, K, SA, SB) has a developer container 24a for storing a two-component developer containing non-magnetic toner and a magnetic carrier, as shown in FIG. The developer contained in the developer container 24a is rotated and held, and the developing roll 24b that conveys the developer in the vicinity of the photosensitive drum 21 and faces the developing area is rotated. A stirring and conveying member 24c that conveys to the developing roll 24b while stirring, and a layer thickness regulating member 24d that regulates the amount (layer thickness) of the developer held on the developing roll 24b are provided.

  In each of the developing devices 24, a developing bias is supplied to the developing roller 24b from a developing power supply unit 16D (FIG. 9), and the developing roller 24b and the agitating / conveying member 24c are rotated by a rotation driving device 28 (rotational driving). Part 16A: Receives power from FIG. 9) and rotates in a required direction. The toner of the developer in each developing device 24 is rubbed with the carrier by being conveyed in the developer container 24a while being agitated by the agitating / conveying member 24c, and thereby has a required polarity (negative polarity in the first embodiment). Is triboelectrically charged. Further, the toner in the developer of the special colors SA and SB is composed of, for example, a color material that is difficult or impossible to express with the above four colors. Specifically, toners other than the above four colors, foamable toner for Braille, fluorescent color toner, toner for improving gloss, and the like.

  Further, as shown in FIG. 2, the developing device 24 (Y, M, C, K, SA, SB) is supplied with each developer by a developer supply system 5. The supply system 5 is a detachable and replaceable developer cartridge 50 (non-magnetic toner containing a magnetic carrier) for each of four colors (Y, M, C, K) and special colors (SA, SB). Y, M, C, K, SA, SB) and a replenishing device 60 (Y, M, C, K, SA, SB) that transports the replenishment developer of each developer cartridge 50 to each developing device 24 by a necessary amount. SB).

  Each of the replenishing devices 60 receives and temporarily stores the replenishment developer discharged from the discharge port of each developer cartridge 50, and sends the stored replenishment developer toward each developing device 24. Is. The replenishment developer sent out from each replenishing device 60 is conveyed to each developing device 24 through the connection conveying device 64. Reference numeral 55 in FIG. 2 and the like is a drive device that rotationally drives the conveying member 52 that conveys the replenished developer in the developer cartridge 50 toward the discharge port. Reference numeral 65 denotes a driving device that rotationally drives a delivery member 62 and the like that sends out a part of the replenishment developer stored in the replenishment device 60 toward the delivery port. Reference numeral 63 denotes a drive device that is stored in the replenishment device 60. This is an agitating and conveying member that conveys the replenishing developer being agitated. Reference numeral 67 denotes a remaining amount detection sensor that detects whether or not the set value of the replenishment developer stored in the replenishing device 60 is greater than or equal to the set value, and reference numeral 29 denotes the developer stored in the developing device 24. This is a density detection sensor that detects the toner density (weight percentage of toner in the developer).

  Further, the developing device 24 (Y, M, C, K, SA, SB) has a part of the developer (a magnetic carrier and a carrier) in order to cope with the deterioration of the carrier of the developer stored in the developer container 24a. The non-magnetic toner adhering thereto is discharged to the outside of the developing device 24. A so-called trickle development method is employed. The part of the developer is discharged through a discharge port through which a part of the developer conveyed by the agitating / conveying member 24c gets over one end of the developer container 24a. The developer discharged from each developing device 24 is collected by a collection system 100 described later.

  The primary transfer device 25 is a contact-type transfer device including a primary transfer roll that rotates in contact with the surface of the photosensitive drum 21 (via an intermediate transfer belt 31 described later) and is supplied with a primary transfer bias. As the primary transfer bias, a DC voltage or the like indicating a polarity opposite to the charging polarity of the toner is applied from the transfer power supply unit 16E (FIG. 9). The primary transfer device 25 may be handled as constituting the intermediate transfer device 30. The drum cleaning device 26 contacts the surface of the photosensitive drum 21 after passing through the primary transfer position, and collects the adhering matter such as the toner removed by the elastic blade 26a and the elastic blade 26a that removes the adhering matter such as residual toner. Then, it is constituted by a delivery member 26b or the like that is driven so as to be sent out to a collection system 100 described later.

  As shown in FIG. 1 and the like, the intermediate transfer device 30 is disposed so as to exist at a position below each image forming device 20 (Y, M, C, K, SA, SB). The intermediate transfer device 30 includes an intermediate transfer belt 31 that rotates in a direction indicated by an arrow while passing through a primary transfer position between the photosensitive drum 21 and the primary transfer device 25 (primary transfer roll). A plurality of support rolls 32a to 32f that are held in a desired state from the inner surface and are rotatably supported, and a secondary transfer roll 35 that rotates in contact with the intermediate transfer belt 31 supported by the support roll 32e with a predetermined pressure. And a belt cleaning device 36 that removes adhering matter such as toner and paper dust remaining on the intermediate transfer belt 31 after passing through the secondary transfer roll 35.

  As the intermediate transfer belt 31, for example, a belt formed of an endless belt having a predetermined thickness using a material in which a resistance adjusting agent such as carbon is dispersed in a synthetic resin such as polyimide resin or polyamide resin is used. . The support roll 32a is configured as a drive roll, and the support roll 32c is configured as a tension applying roll. A secondary transfer bias is supplied to the support roll 32e (or the secondary transfer roll 35) from the transfer power supply unit 16E (FIG. 9). As the secondary transfer bias, a DC voltage or the like indicating the same polarity (or opposite polarity) as the charging polarity of the toner is supplied. The belt cleaning device 36 comes in contact with the surface of the intermediate transfer belt 31 after passing through the secondary transfer position, and removes adhered matter such as residual toner, and adhered matter such as toner removed by the elastic blade 36a. And a delivery member 36b that is driven so as to be sent out to a collection system 100 described later.

  The paper feeding device 40 is disposed so as to exist at a position below the intermediate transfer device 30. The sheet feeding device 40 is attached so that it can be pulled out to the front side (side surface that the operator faces when using it) of the housing 10, and is a single unit that accommodates recording paper 9 of a desired size, type, etc. Or a plurality of) paper containers 41 and a feeding device 42 that feeds the recording paper 9 from the paper container 41 one by one. The recording paper 9 sent from the paper feeding device 40 is connected to the intermediate transfer belt 31 in the intermediate transfer device 30 via a plurality of paper conveyance roll pairs 43a, 43b, 43c,. The sheet is conveyed to a secondary transfer position between the secondary transfer rolls 35.

  The fixing device 45 rotates inside the housing 46 in the direction indicated by the arrow and is heated by heating means so that the surface temperature is maintained at a predetermined temperature. A pressurizing rotator 48 which is rotated in contact with a predetermined pressure in a state substantially along the axial direction is installed. The recording sheet 9 on which an image is formed after the fixing of the toner image by the fixing device 45 is discharged to a housing 10 or the like through a discharge conveyance path constituted by a plurality of conveyance roll pairs and conveyance guide materials. It is transported and accommodated.

  The basic image forming operation by the image forming apparatus 1 is performed as described below. Here, a full-color image formed by combining toner images of four colors (Y, M, C, K) formed using all of the four image forming devices 20 (Y, M, C, K). A pattern (full color mode) of the image forming operation to be formed will be described.

  When there is an instruction for an image forming operation (printing) from the above-described image information device or the like, in each of the four image forming apparatuses 20 (Y, M, C, K), first, each photosensitive drum 21 rotates in the direction indicated by the arrow. Each charging device 22 charges the surface of each photosensitive drum 21 to a required polarity (negative polarity in the first embodiment) and potential. Subsequently, the exposure device 23 emits light on the charged surface of the photosensitive drum 21 based on the image data separated into the color components (Y, M, C, K) transmitted from the image processing device 27. Exposure is performed by irradiating light to form an electrostatic latent image of each color component composed of a required potential difference. Next, each developing device 24 (Y, M, C, K) corresponds to an electrostatic latent image of each color component formed on the photosensitive drum 21 with a corresponding color (Y) charged to a required polarity (minus polarity). , M, C, K) toner is supplied and electrostatically adhered.

  The developing process at this time will be described in detail. In each developing device 24, the developing roll 24b and the agitating / conveying member 24c are rotationally driven, and the developer G accommodated in the developer accommodating portion 24a is conveyed by the agitating / conveying member 24c. It is conveyed to the developing roll 24b while being stirred. The developer G that has been stirred and conveyed adheres to the rotating developing roll 24b, is regulated to a required thickness by the layer thickness regulating member 24d, and is then conveyed to the developing region facing the photosensitive drum 21. The developer G (toner component in the first embodiment) transported to the developing area is supplied to the photosensitive drum 21 by a developing electric field formed by a developing bias supplied between the developing roll 24 b and the photosensitive drum 21. And adhere to the electrostatic latent image portion. On the other hand, most of the developer G that has not been subjected to the development is returned to the developer accommodating portion 24a by the rotating developing roll 24b. The electrostatic latent images of the respective color components formed on the respective photosensitive drums 21 in this way are each developed with the corresponding color toners by passing through the developing device 24, and are thus four colors (Y, M, C, K) is visualized as a toner image.

  Next, the toner images of the respective colors formed on the photosensitive drums 21 of the respective image forming devices 20 (Y, M, C, K) are sequentially applied to the intermediate transfer belt 31 of the intermediate transfer device 30 by the primary transfer device 25. The primary transfer is performed so as to be superimposed on each other. Further, the intermediate transfer device 30 holds the toner image primarily transferred to the intermediate transfer belt 31 and conveys it to the secondary transfer position, and then the secondary transfer roll 35 is conveyed from the paper supply device 40 and fed into the sheet 9. Secondary transfer in a batch. The sheet 9 on which the toner image has been secondarily transferred is peeled off from the intermediate transfer belt 31 and then introduced into the fixing device 45, where it undergoes necessary fixing processing (heating and pressing), and the toner image is fixed. The sheet 9 after fixing is discharged and stored in a discharge storage section (not shown) formed in the housing 10, for example, in an image forming operation that only forms an image on one side.

  Through the above operation, the sheet 9 on which a full color image formed by combining four color toner images is output.

  In addition, when the image forming apparatus 1 forms toner images of the special colors SA and SB, the image forming apparatuses 20SA and 20SB operate similarly to the image forming apparatus 20 (Y, M, C, and K) described above. As a result, toner images of special colors SA and SB are formed on the respective photosensitive drums 21. The toner images of the special colors SA and SB formed by the image forming devices 20SA and 20SB are finally transferred to the recording paper 9 (for example, together with toner images of other colors) by the intermediate transfer device 30. The The toner images of special colors SA and SB transferred to the recording paper 9 are fixed by the fixing device 45.

  Further, in the image forming operation by the image forming apparatus 1, the surface after the primary transfer of each photosensitive drum 21 in each image forming device 20 (Y, M, C, K, SA, SB) is cleaned by the drum cleaning device 26. The intermediate transfer belt 31 of the intermediate transfer device 30 is cleaned by the belt cleaning device 36. Further, in each developing device 24 (Y, M, C, K, SA, SB) in each image forming device 20, a part of the developer is discharged to the outside by the trickle developing method. At this time, the drum cleaning device 26 removes the most untransferred toner that has not been primarily transferred, and the belt cleaning device 36 removes the most untransferred toner that has not been secondarily transferred. In each developing device 24, the carrier and the toner adhering to the carrier are discharged. The toner and the like removed by the drum cleaning device 26 and the belt cleaning device 36 and the carrier and toner discharged from each developing device 24 are recovered by the recovery system 100 as described later.

  Next, the collection system 100 will be described.

  As shown in FIG. 3 and the like, the collection system 100 includes a collection conveyance device 101 that mainly conveys toner and carrier, and two collection containers 200A and 200B that contain the toner and carrier conveyed by the collection conveyance device 101. Has been.

  The collection transport device 101 transports the toner and the carrier sent together from the developing device 24 and the drum cleaning device 26 of each image forming device 20 (Y, M, C, K, SA, SB) together as one. A first conveying device 110, a second conveying device 120 that conveys toner sent from the belt cleaning device 36 of the intermediate transfer device 30, and a toner and a carrier conveyed from the first conveying device 110 and the second conveying device 120. The third transport device 130, the fourth transport device 140 for transporting the toner and the carrier transported from the third transport device 130, and the toner and the carrier transported by the fourth transport device 140 in any of the collection containers 200A and 200B. A fifth transport device 150 that transports the cradle is provided.

  The first transport device 110 is a tubular tube disposed in a position that is substantially horizontal at a position below the image forming devices 20 (Y, M, C, K, SA, and SB) at a rear portion of the housing 10. The member 112 includes a conveyance member 113 that rotates in the internal space of the tubular member 112 and conveys toner and carrier downstream in the conveyance direction, and a first driving device 114 that transmits rotational power to the conveyance member 113. Yes. The transport direction is a direction indicated by an arrow in FIG. Further, the downstream side in the transport direction of the first transport device 100 is the side on which the special color image forming device 20SA is arranged in the first embodiment.

  The tubular member 112 of the first conveying device 110 has a space between the discharge port of the developing device 24 and the delivery port of the drum cleaning device 26 in each image forming device 20 (Y, M, C, K, SA, SB). Connected transport devices 115 (Y, M, C, K, SA, SB) are connected to transport toner and carrier, respectively. In each of the connection conveyance devices 115, the discharge port of the developing device 24 and the delivery port of the drum cleaning device 26 and the tubular member of the first conveyance device 110 in each image forming device 20 (Y, M, C, K, SA, SB). 112, a tubular member 116 disposed substantially along the vertical direction (vertical direction) so as to connect to 112, and a collapsing member that advances and retreats in the vertical direction in the internal space of the tubular member 116 to break down toner or the like adhering to the inner wall. 117 and a driving device 118 that transmits power for moving the breaking member 117 forward and backward. In the first embodiment, as the breaking member 117 to be broken, a coil spring without a rotating shaft and spirally wound with a wire is used.

  The second conveying device 120 includes a tubular member 122 disposed at a position below the belt cleaning device 36 of the intermediate transfer device 30 at a position behind the housing 10 so as to be in a substantially horizontal state, and the inside of the tubular member 122 A conveyance member (not shown) that rotates in the space and conveys the toner downstream in the conveyance direction, and a second driving device 124 that transmits rotational power to the conveyance member. The downstream side in the transport direction of the second transport device 120 is the downstream end side of the tubular member 112 of the first transport device 110 in which the special color image forming device 20SA is arranged in the first embodiment.

  The tubular member 122 of the second transport device 120 is configured to be directly connected to the delivery port of the belt cleaning device 36. In addition, when the 3rd conveying apparatus 130 is arrange | positioned in the position away from the belt cleaning apparatus 36 in the position on the opposite side to the image forming apparatus 20 side, the 2nd conveying apparatus 120 may abbreviate | omit the installation. it can. In this case, for example, the delivery port of the belt cleaning device 36 may be connected to the tubular member 112 of the first transport device 110.

  The third conveyance device 130 is arranged along the substantially vertical direction from the joint portion of the tubular member 112 of the first conveyance device 110 and the tubular member 122 of the second conveyance device 120 toward the fourth conveyance device 140 on the lower side. A tubular member 132 to be moved, a breaking member (coil spring in the first embodiment) 133 that moves forward and backward in the internal space of the tubular member 132 to break up toner adhering to the inner wall, and a breaking member 133 is moved forward and backward. And a third driving device 134 for transmitting power for the purpose.

  As shown in FIG. 3 and FIG. 4, the fourth conveying device 140 is in a state where it intersects with the lower end portion of the tubular member 132 of the third conveying device 130 and is arranged so as to be almost horizontal as a whole. 142, a conveyance member 143 that rotates in the internal space of the tubular member 142 and conveys toner and carrier toward the downstream side in the conveyance direction, and a fourth drive device 144 that transmits rotational power to the conveyance member 143. . The downstream side in the transport direction of the fourth transport device 140 in the first embodiment is the side on which the containers 200A and 200B are disposed. Moreover, as the conveyance member 143, the screw auger which formed the conveyance blade | wing of the form spirally wound around a rotating shaft is used.

  As shown in FIGS. 3 and 4, the fifth transport device 150 is disposed and connected to the lower portion of the downstream end portion of the tubular member 142 of the fourth transport device 140, and is disposed so as to be substantially horizontal as a whole. A tubular member 152, a conveying member 153 that can rotate in the inner space of the tubular member 152 and convey toner and carrier in both directions, and a first member that transmits rotational power in the forward and reverse directions to the conveying member 153. 5 drive device 154. The tubular member 152 is connected to the downstream end portion of the tubular member 142 of the fourth transport device 140 via the connecting pipe portion 155, while being present at both sides of the connecting pipe portion 155 and protruding downward. It is configured to be connected to the receiving portions 210A and 210B of the containers 200A and 200B via the discharge portions 156 and 157 arranged in a state.

  The fifth transport device 150 has a transport switching function as a transport destination switching mechanism. That is, as shown in FIG. 4, when the conveyance member 153 is rotated in the forward rotation direction C <b> 1 by controlling the rotation direction of the rotational power generated by the fifth driving device 154, the conveyance member 153 is the fourth The toner and carrier transported from the transport device 140 are transported toward the first discharge unit 156 connected to the first container 200A, and finally stored in the first container 200A. On the other hand, when the conveyance member 153 is rotated in the reverse rotation direction C2, the toner and the carrier conveyed by the conveyance member 153 from the fourth conveyance device 140 are directed to the second discharge unit 157 connected to the second container 200B. And finally accommodated in the second container 200B.

  Each of the containers 200A and 200B is a container having an approximately rectangular shape in appearance as shown in FIGS. 3, 5, 6 and the like, and a receiving port 210A for receiving toner, a carrier and the like on its upper surface portion 201. 210B is formed, and handle portions 220A and 220B are formed on one side surface portion 202 thereof. The containers 200A and 200B are detachably mounted on a container mounting portion formed in the lower portion of the housing 10 so that they can be exchanged. In the mounting, the receptacles 210A and 210B are placed below the connection pipe portions 156 and 157 in the fifth transfer device 150 of the collection system 100 by fitting the containers 200A and 200B into the installation frame 105 provided in the container mounting portion. It exists and stays connected.

  Further, when the containers 200A and 200B are mounted on the container mounting portion of the casing 10, the side surface portion 203 opposite to the side surface portion 202 on which the handle portions 220 of the containers 200A and 200B are formed faces each other. An accommodation detection sensor that measures the magnetic permeability of the magnetic carrier accommodated in the containers 200A and 200B and detects that the accommodation amount of the non-magnetic toner T and the magnetic carrier C accommodated in the portion exceeds the set amount. 106A and 106B are provided. Furthermore, mounting detection sensors 107A and 107B for detecting whether or not the containers 200A and 200B are mounted (presence / absence) are provided in the container mounting portion of the housing 10, respectively.

  Among these, the accommodation detection sensor 106 is installed so that the detection surface portion 106a approaches or contacts the side surface portion 203 of the containers 200A and 200B, and detects the magnetic permeability of the magnetic carrier in the container 200 in this state. It is like that. In addition, the accommodation detection sensor 106 detects that when the accommodation amount reaches the set amount L1, the output becomes a value higher than the threshold value, and when the output is caught, the accommodation amount becomes the set amount L1 or more. Will be. The amount of storage corresponding to the set amount L1 is, for example, slightly smaller than the amount of storage assumed to be full (dashed line Lmax) as shown in FIG. This is the approximate amount to do. The container 200A (200B) is shown on the left side in FIG. 6, and the capacity (maximum capacity) CP of the container 200 is shown on the right side.

  In the collection system 100, the replenishing device 60 after the output of the capacity detection sensor 106 has reached a value indicating that the container 200A, 200B is full of toner and carrier contained therein is equal to or greater than the set value L1. It is determined by detecting when the accumulated value of the replenishment time (driving time of the sending member 62) or the accumulated value of the number of pixels of the latent image formed by the exposure device 23 exceeds a preset threshold value.

  The collection system 100 operates as follows.

  The collection system 100 operates in conjunction with the time when the image forming device 20 and the intermediate transfer device 30 are operated to form a toner image (image forming operation). In other words, in the recovery system 100, the first to fifth transport devices 110, 120, 130, 140, 150, which are the recovery transport device 101, and the transport members in the connection transport unit 115 are driven by the start of the drive devices. .

  As a result, the waste toner T1 discharged from the developing device 24 in each image forming device 20 by the trickle developing method and the removed toner T2 removed and sent out by the carrier C1 and the drum cleaning device 26 are connected to each connection transport device 115 (Y , M, C, K, SA, SB), and is conveyed to the tubular member 112 of the first conveyance device 110 and then conveyed in the conveyance direction indicated by the arrow by the rotation-driven conveyance member 113. . Further, after the removed toner T3 removed and sent out by the belt cleaning device 36 in the intermediate transfer device 30 falls from the discharge port in the belt cleaning device 36 to the tubular member 122, the second transport device 120 moves in the transport direction indicated by the arrow. Be transported.

  Subsequently, the toners T <b> 1 to T <b> 3 and the carrier C <b> 1 respectively conveyed by the first conveyance device 110 and the second conveyance device 120 are conveyed in a state of falling by the third conveyance device 130, and then are fourth by the fourth conveyance device 140. 5 It is conveyed in the conveyance direction shown by the arrow toward the conveyance device. The toners T <b> 1 to T <b> 3 and the carrier C <b> 1 transported to the fifth transport device 150 are switched in the transport direction (accommodation destination) by switching the rotation direction of the transport member 153 in the fifth transport device 150. It is conveyed so as to reach either the discharge unit 156 or the discharge unit 157, and finally falls from the discharge unit 156 or the discharge unit 157 and is stored in the storage space of the first container 200A or the second container 200B.

  Further, in the collection system 100, the accommodation detection sensors 106A and 106B measure the permeability of the magnetic carrier C1 and detect the accommodation amounts of the toners T1 to T3 and the carrier C1 accommodated in the first container 200A and the second container 200B. Done. In addition, as described above, when the above-described replenishment time or the cumulative value of the number of pixels exceeds the threshold after the output of any one of the capacitance detection sensors 106A and 106B has reached a value indicating that it is greater than or equal to the set amount L1. Then, it is determined that one of the containers 200A and 200B is full, and for example, a notification is made to prompt the user to replace the full container 200.

  In the image forming apparatus 1, as shown in FIG. 7, a toner image (hereinafter, this toner image is abbreviated as “special toner image”) ST that is not transferred to the recording paper 9 in each image forming device 20 is formed on the photosensitive drum 21. Each of the toner discharge operations to be formed is executed.

  As the toner releasing operation, for example, a special toner different from the toner image constituting the image formed on the recording paper 9 is used to cope with the deterioration of the toner of the developer stored in the developing device 24 in the image forming device 20. There is an operation in which an image is formed by development and released to the outside of the developing device 20.

  This toner discharge operation is performed for the following reason. That is, first, in the developing device 24, when image formation (development) with relatively low image density (image area ratio is small) is continuously performed, the image is not used for development and is not used for development by the developing roll 24b. Since the chance of returning to the developer accommodating portion 24a and receiving stress such as a stirring action by the stirring and conveying member 24c and a rubbing action by the layer regulating member 24d increases, the characteristics of the toner deteriorate (external additives such as a charge adjusting agent). And deterioration of charging characteristics due to embedding in toner particles, etc.), and this may lead to poor development due to the deterioration of the toner, and hence a reduction in image quality. In order to reduce the amount of such deteriorated toner, a part of the toner in the developing device 24 is intentionally discharged to the outside of the developing device 24, thereby reducing the toner density in the developing device 24. A new developer (toner) is replenished to the developing device 24 from the developer cartridge 50 by the replenishment system 5 and replaced (refreshed).

  Further, as another toner discharging operation, a special toner image may be formed on the photosensitive drum 21 in order to remove discharge products and the like adhering to the surface of the photosensitive drum 21 together with a large amount of toner by the drum cleaning device 26. In this toner discharge operation, when a discharge product generated in the charging process adheres to the surface of the photosensitive drum 21, a part of the charge constituting the electrostatic latent image easily moves due to moisture absorption by the discharge product, Since an image quality defect called so-called image flow may occur, it is executed to prevent it.

  Further, as another toner discharging operation, a special toner image may be formed on the photosensitive drum 21 in order to remove oil components adhering to the surface of the photosensitive drum 21 together with a large amount of toner by the drum cleaning device 26. This toner discharge operation is performed by using oil contained in the toner of the image formed on one side (first side) of the recording paper 9 when the double-sided image forming operation for forming images on both sides of the recording paper 9 is continuously executed. The components adhere to the intermediate transfer belt 31 during the secondary transfer of the image (toner image) to the other surface (second surface), and transfer to the photosensitive drum 21 when the intermediate transfer belt 31 passes the primary transfer position. Since the toner image may not be satisfactorily formed on the photosensitive drum 21 due to the adhesion, the process is executed to prevent this.

  In the toner discharging operation, a toner image having a high image density is formed on the photosensitive drum 21 as a special toner image ST in each image forming device 20, and a part of the toner is discharged from the developing device 24, and the special toner image ST is intermediately transferred. The drum is removed by the drum cleaning device 26 without being transferred to the belt 31. At this time, the primary transfer device 25 is not supplied with the primary transfer bias from the transfer power supply unit 16E, or is supplied with a bias under a condition that makes it difficult for the toner to be transferred to the intermediate transfer belt 31 to the recording paper 9 of the special toner image ST. Is preventing the transfer of. In this toner discharge operation, it is also possible to perform a primary transfer of a part or all of the special toner image ST to the intermediate transfer belt 31 and remove it by the belt cleaning device 36. In this case, at the secondary transfer position, a secondary transfer bias is not supplied from the transfer power supply unit 16E, or a bias is applied so that the toner is not easily transferred to the secondary transfer roll 35.

  Also, the timing for executing this toner discharge operation is, for example, the timing after the preset low-density image formation (development) is continuously performed for the set number of sheets, or the temperature and humidity in the housing 10 in advance. The time when the set condition is satisfied, the time after the predetermined number of double-sided image formations are continuously performed, and the like. Further, the toner discharge operation is executed by setting a special operation mode different from the image forming operation, or is executed by being incorporated in the image forming operation. When the image forming operation is incorporated and executed, the special toner image ST is formed in an area where no image (toner image) is formed in the image forming effective area of the photosensitive drum 21.

  For example, as shown in FIG. 7, the area where no image is formed is shown in an image formation effective area of the photosensitive drum 21 (in FIG. 7, the surface portion of the drum 21 serving as this area is developed in a plane. ), A non-image forming area S existing between the image Ia forming area E1 and the image Ib forming area E2 to be formed on one side of the recording paper 9. Further, the area where no image is formed includes non-image forming areas ES that are not image forming areas E1 and E2 among the effective image forming areas. A symbol EBG in FIG. 7 indicates a background portion where the image I is not formed in the image forming region E.

  On the other hand, when this toner discharge operation is executed, a relatively large amount of toner T4 (FIG. 3) constituting the special toner image ST is removed by the drum cleaning device 26, and the container 200 (A, B) is collected by the collection system 100. ). When the toner T4 is transferred to the intermediate transfer belt 31, the toner T4 is removed by the belt cleaning device 36 and collected. As a result, when the toner T4 constituting the special toner image ST is collected by the collection system 100, the ratio of the toner T in the toners T1 to T4 and C1 stored in the container 200 (A, B) is the magnetic carrier C. It will increase rapidly compared to the proportion.

  In this case, the toner T4 constituting the special toner image ST is accommodated in the part of the container 200 (A, B) corresponding to the detection region to be detected by the accommodation detection sensor 106 (A, B) of the collection system 100. The toner detection ratio 106 (A, B) sufficiently measures the magnetic permeability of the magnetic carrier C because the ratio of the magnetic carrier C decreases as the ratio of the toner T rapidly increases compared with the ratio of the magnetic carrier C. In some cases, it may not be possible to detect it even though the accommodation amount has reached the set amount L1 (FIG. 6). FIG. 8 shows the result of measuring the fluctuation state of the output of the accommodation detection sensor 106 with respect to the toner concentration. FIG. 8 shows that when the output of the accommodation detection sensor 106 reaches a value near or below the limit value, it cannot be normally detected that the set amount Y has been reached.

  If an erroneous detection (undetectable) of the storage detection sensor 106 (A, B) occurs, the toner 200 and the carrier exceeding the set amount L1 are stored in the container 200 (A, B) as described above. The full detection of the container 200 (A, B) is not normally performed. That is, since there is no detection result exceeding the set amount L1 from the accommodation detection sensor 106, the replenishment time or pixel count operation for considering a full state is not executed. As a result, the toner and the carrier are successively stored in the container 200 (A, B) and become full, overflowing from the receptacle 210 of the container 200 (A, B), and the overflowed toner causes the casing to overflow. The inside of 10 will be contaminated. Further, the tubular member of the collecting and conveying apparatus 101 is clogged with toner or the like.

  Therefore, in view of the above-described problems, the image forming apparatus 1 is configured to perform a recovery operation of the recovery system 100 and an operation for detecting the amount of container 200 as described below.

  In the first embodiment, as shown in FIG. 6, a virtual part for confirming the necessity of detection by the storage detection sensors 106A and 106B of the containers 200A and 200B where the measurement of the magnetic permeability of the storage detection sensors 106A and 106B is effective is confirmed. The area W is set. Further, as shown in FIG. 11 and the like, the controller 7 to be described later performs image formation executed next when the amount of toner and magnetic carrier accommodated in the containers 200A and 200B reaches the virtual region W. It is determined whether the operation is an image forming operation related to the toner releasing operation (in short, an operation for forming the special toner image ST). Instead, predictive detection is performed to predict and detect that the storage amount has become equal to or greater than the set amount L1 based on the replenishment time of the replenishment device 60 or the cumulative number of pixels of the latent image. Details of this will be described later.

  In addition, as shown in FIG. 11, the control device 7 performs other processing when the amount of toner and magnetic carrier accommodated in one of the containers 200 </ b> A and 200 </ b> B (for example, assumed to be the container 200 </ b> A) reaches the virtual region W. It is determined whether or not the container (the container 200B in the above assumption) is present and whether the amount of the other container (200B) is equal to or larger than the virtual region W, and the other container (200B) exists. When the storage amount of the other container (200B) is determined to be less than the virtual area W, control is performed to switch the storage destination in the switching mechanism 150 in the collection system 100 to the other container (200B). It has become. In addition, as shown in FIG. 11, in the above-described determination, when there is no other container (200B), or there is another container (200B), and the capacity of the other container (200B) is greater than or equal to the virtual region W. When it is determined that the storage amount is the amount, the storage amount in the switching mechanism 150 reaches the virtual area W when it is determined that the next image forming operation is the image forming operation related to the toner release operation. While switching to the container (200A), the above-described prediction detection is performed. Details of this will be described later.

  In the image forming apparatus 1, as shown in FIG. 9, the control device 7 controls various operations such as the image forming operation, the developer replenishing operation, the collecting operation, the toner discharging operation, and the storage amount detecting operation described above. .

  First, the control device 7 includes an arithmetic processing device, a storage element and device, a control device, an input / output device, and the like, and performs a required control operation based on a control program and data stored in the storage element. It is supposed to run. The storage element and the device are constituted by a storage element such as a ROM and a RAM and a recording device such as a magnetic disk device.

  The control device 7 includes a pixel number accumulating unit 13 for accumulating and counting the number of pixels of the latent image, a replenishment time accumulating unit 14 for accumulating and counting the replenishment time by the replenishing device 60, and a toner density sensor. 29, a detector such as a developer remaining amount detection sensor 67, an image processing device 27, a connection communication unit 12, an input / display device (operation panel or the like) 15 for inputting and displaying various information, and the like are connected. Information necessary for control is input from them. The control device 7 includes an image forming control unit 71 that controls operations of the image forming device 20, the intermediate transfer device 30, the paper feeding device 40, and the fixing device 45, and a replenishment control unit 72 that controls the operation of the replenishment system 5. Also connected to the collection control unit 73 for controlling the operation of the collection system 100, the image processing device 27, the connection communication unit 12, the input / display device 15 and the like, control signals necessary for each of those operations are sent. It is supposed to send. The image forming control unit 71, the supply control unit 72, and the collection control unit 73 are configured as a part of the control device 7, but may be configured as a dedicated control device independent of the control device 7.

  The pixel number accumulating unit 13 obtains and counts information on the number of pixels included in the image signal transmitted from the image processing device 27 to the exposure device 23, and the result of the counted number of pixels (count value D: FIG. 6). , FIG. 12) is configured by a storage unit or the like for accumulating and storing. The replenishment time accumulating unit 14 obtains and counts information on the drive time when driving the driving device 65 that drives the delivery member 62 of the control device 7 or the replenishment device 60, and the counted replenishment time. The storage unit is configured to accumulate and store the results (count value D: FIGS. 6 and 12). The pixel number accumulating unit 13 and the replenishment time accumulating unit 14 are prepared for each of the containers 200A and 200B. For example, a part of the recording element (RAM) in the control device 7 may be used as the storage unit.

  The image formation control unit 71 includes a rotation drive device (rotation drive unit) 16A that transmits rotation power to the drive members of the image formation device 20, the intermediate transfer device 30, the paper feeding device 40, and the fixing device 45 that are the control targets. First, a charging power supply unit 16B for supplying a charging bias, an exposure driving unit 16C for driving the exposure device 23, a developing power supply unit 16D for supplying a developing bias, a transfer power supply unit for supplying a primary transfer bias and a secondary transfer bias 16E etc. In the toner discharge operation, a control signal necessary for the operation is transmitted through the image forming control unit 71. The replenishment control unit 72 is connected to the rotation driving devices 55 and 56 in the replenishment system 5 that is the control target.

  The collection control unit 73 is a fifth storage destination switching mechanism that switches the storage destinations of the toner and the magnetic carrier, including the drive devices 114, 118, 124, 134, and 144 in the transport device 101 of the recovery system 100 that is the control target. The transport device 150 (the fifth drive device 154) is connected to a prediction detection switching unit 75 that is a switch SW (FIG. 10) that performs switching when performing the above-described prediction detection. The prediction detection changeover switch SW is composed of software and a storage unit configured to store and hold a state in which prediction detection is performed ("ON" state) and a state in which prediction detection is not performed ("OFF" state). The

  Hereinafter, the recovery operation and the container capacity detection operation in the recovery system 100 of the image forming apparatus 1 will be described in detail.

  First, the capacity of the containers 200 (A, B) is set as follows. First, as shown in FIG. 6, the container 200 (A, B) is divided into four accommodation amount states 0 to 3 according to the accommodation amount.

  The state 1 is a state when the accommodation amount is in the virtual area W described above. The virtual region W is a part of the container 200 where the measurement of the magnetic carrier permeability is effective by the accommodation detection sensor 106 (A, B), and the necessity of detection by the accommodation detection sensor 106 (A, B) is confirmed. Set as an area. State 0 is a state in which the accommodation amount is not full and the accommodation is sufficiently possible. The state 2 is a state before the state 2 becomes full. State 3 is a state in which the capacity is full.

  Next, the detection of the four accommodation states 0 to 3 is performed as follows.

  Regarding the state 0 and the state 1, it is determined whether or not the first count value D1 obtained by accumulating the replenishment time or the number of pixels from the initial stage (new stage) of the container 200 reaches a first threshold value X set in advance. Predicted by detection and detected. The first threshold value X is set in advance as a cumulative value (D1) of the replenishment time or the number of pixels when the toner and carrier storage amounts are expected to reach the lower limit point of the virtual area W through experiments or calculations. It is.

  Regarding the state 2, in the case of detection by the accommodation detection sensor 106, detection is made when the sensor output becomes “High”, or in the case of prediction detection, the first count value D1 of the replenishment time or the number of pixels is previously set. It is predicted and detected by determining whether or not the second threshold value Y to be set is reached. The second threshold Y is set in advance as an accumulated value (D1) of the replenishment time or the number of pixels when the toner and carrier storage amounts are expected to reach the upper limit point of the virtual area W through experiments or calculations. It is.

  For state 3, after detection information indicating that state 2 has been reached (information when the output of the accommodation detection sensor 106 becomes “High” or information where the count value D1 is equal to or greater than the second threshold Y) is obtained. The second count value D2 obtained by accumulating the replenishment time or the number of pixels is predicted and detected by determining whether or not the second count value D2 reaches a preset third threshold value Z. The third threshold value Z is a cumulative value (D2) of the replenishment time or the number of pixels when the toner and carrier storage capacity is expected to reach the full capacity (Lmax) by experiments or calculations in advance. Is set as

  Further, the four accommodation states 0 to 3 are configured to be confirmed by the control device 7 through processing steps as shown in FIG. The confirmation of the container capacity state is performed at a preset time (for example, a time such as replenishment time or addition of the number of pixels).

  As shown in FIG. 10, after confirming the first count value (cumulative information) D1 of the replenishment time or the number of pixels, the first count value D1 is less than the first threshold value X as shown in FIG. Is determined (steps S10 to S11). At this time, if the first count value D1 is less than the first threshold value X, it is determined that the accommodation amount has not reached the lower limit point of the virtual area W, and the accommodation amount state is determined to be “state 0”.

  If it is determined in step S11 that the first count value D1 is not less than the first threshold value X (is greater than or equal to the threshold value X), the state of the prediction detection changeover switch SW is confirmed (S12). If the changeover switch SW is in the “OFF state”, the output state of the accommodation detection sensor 106 (A, B) is confirmed (S13). At this time, if the output is “Low” (an output value smaller than the threshold value that becomes High), it is considered that the accommodation amount does not reach the set amount L1 and is within the virtual area W, and the accommodation amount state is “ It is determined that the state is “1”.

  When it is determined in step S12 that the changeover switch SW is in the “ON state”, it is determined whether or not the first count value D1 is less than the second threshold value Y (S14), and the first count value D1 is determined. Is less than the second threshold Y, it is determined that the accommodation amount does not reach the set amount L1 and is within the virtual area W, and the accommodation amount state is determined to be “state 1”.

  On the other hand, when it is determined in step S13 that the output of the accommodation detection sensor 106 (A, B) is “High”, or in step S14, the first count value D1 is not less than the second threshold Y (is greater than or equal to the threshold Y). ), After obtaining the second count value (cumulative information) D2 of the replenishment time or the number of pixels, it is determined whether or not the second count value D2 is less than the third threshold value Z. (Steps S15 to S16).

  At this time, when it is determined that the second count value D2 is less than the third threshold value Z, the accommodation amount reaches the set amount L1 and exceeds the virtual area W but exceeds the amount Lmax that is assumed to be full. It is determined that the accommodation amount state is “state 2”.

  When it is determined that the second count value D2 is not less than the third threshold value Z (is greater than or equal to the threshold value Z), it is considered that the capacity has exceeded the amount Lmax that is assumed to be full, and the capacity state is full. It is determined that the state is “state 3”.

  In this image forming apparatus 1, when it is determined that the accommodation amount state is any one of “0 to 2”, as shown in FIG. 6, the “image forming operation standby state” in which the toner image forming operation can be continued. It is set to be judged to be. In other words, in this case, the image forming apparatus 1 is in a state in which the formation of the toner image accompanying the image formation and the formation of the special toner image ST accompanying the toner discharging operation can be performed thereafter.

  On the other hand, when it is determined that the storage amount state is any one of “3”, the recovery operation to the container 200 of the recovery system 100 cannot be continued. Therefore, as shown in FIG. It is set so that it is determined that the image forming operation is in a “prohibited state of image forming operation”. In this case, as shown in FIG. 6, a warning message or the like for prompting the user to replace the container 200 (A, B) determined to be in state 3 (full) is displayed on the input display unit 15 or the like.

  Next, the collection operation and the container capacity detection operation in the collection system 100 are performed as follows.

  First, as shown in FIG. 11, when there is a request for an image forming operation (in the first embodiment, a toner image forming operation or a special toner image forming operation in the first embodiment), the control device 7 The capacity state is confirmed (S20 to S21).

  When the storage amount state is “state 0”, an image forming operation is executed in the image forming device 20, the intermediate transfer device 30 and the like (S22), and the recovery amount of the container 200 (A, B) in the collection system 100 is reached. Detection is performed by the detection of the accommodation detection sensor 106 (A, B) (S23), and is continued until all image forming operations required at that time are completed (S24). The image forming operation at this time is a toner image forming operation which is a requested normal image or a special toner image ST forming operation related to the toner releasing operation. In the collection system 100, for example, the toner and the carrier are set so as to be transported and accommodated in the first container 200A.

  Incidentally, at this time, if the output of any of the accommodation detection sensors 106 (A, B) becomes “High”, it means that the accommodation amount state of the container 200A has reached the set amount L1, so that it becomes “state 2”. In addition, the cumulative value of the replenishment time or the number of pixels starts to be counted as the second count value D2.

  When the accommodation amount state is “state 1”, the requested mode (type) of the image forming operation is confirmed (S25). In this case, when the image forming mode is a mode other than the above-described “toner releasing operation”, that is, a normal image forming operation, the processing operations (S22 to S24) as described above are similarly performed.

  When it is determined that the image forming mode is the “toner release operation” mode, the presence or absence of another container is confirmed (S26), and there is no other container (second container 200B in the first embodiment) (for example, When it is determined that the container 200B is not attached to the attachment portion), the toner T4 of the special toner image ST formed by the toner discharging operation is conveyed by the collection system 100 and finally the accommodation amount is “state 1”. Is stored in the first container 200A (that is, the region of the virtual region W), and instead of detection by the storage detection sensor 106A, switching to prediction detection is performed (S28). Specifically, the prediction detection selector switch SW is set to the “ON state”.

  Subsequently, an image forming operation of the special toner image ST related to the requested toner releasing operation is performed (S29), and the collection amount of the container 200 (A, B) is detected by predictive detection in the collection system 100 ( S30), and continues until the image forming operation required at that time is completed (S31). In this case, since the toner T4 of the special toner image ST is accommodated in the first container 200A in the “accommodating state 1” by the collection system 100, the occupation ratio of the toner in the container 200A increases rapidly ( The ratio of the magnetic carrier is reduced).

  In the predictive detection at this time, as described above, it is determined whether or not the first count value D1 of the replenishment time or the number of pixels exceeds the second threshold Y, and thereby the amount of the container 200A is detected. It will be. At this time, if the first counter value D1 is equal to or greater than the second threshold value Y, the container 200A has reached the set amount L1, so the state is changed to "state 2". The accumulated value of the number of pixels starts to be counted as the second count value D2. By performing this predictive detection, the amount of container 200A is reliably detected regardless of the phenomenon in which the toner occupation ratio rapidly increases in the virtual region W of the container 200A.

  When it is determined in step S26 that there is another container (200B), the accommodation amount state of the other container (200B) is confirmed (S27).

  In this case, when it is confirmed that the storage amount state of the other container 200B is “state 1” or “state 2”, the toner T4 of the special toner image ST cannot be stored in the other container 200B. As in the case where there is no other container (200B) in step S26, the special toner image ST is imaged and the container 200A is accommodated after switching to prediction detection, as in the case where there is no other container (200B) in step S26. Predictive detection is performed for the amount (S28 to S31). Also in this case, by performing the predictive detection, the amount of the container 200A is reliably detected regardless of the phenomenon in which the toner occupation ratio rapidly increases in the virtual region W of the container 200A.

  On the other hand, when it is confirmed in step 27 that the accommodation amount state of the other container (200B) is “state 0”, the accommodation destination of the toner T4 of the special toner image ST is switched (S32). Specifically, the conveyance direction (FIG. 4) is changed to be sent to the second container 200B by switching the rotation direction of the conveyance member of the fifth conveyance device 150 in the collection system 100.

  Subsequently, an image forming operation of the special toner image ST requested in the image forming apparatus 20 or the like is performed (S33), and the storage amount of the second container 200B is detected by the storage detection sensor 106B in the collection system 100 ( These are continued until the image forming operation is completed (S35).

  As a result, when a plurality of containers 200 are installed, the storage of the toner T4 of the special toner image ST in the container 200A is prohibited at the stage where the storage amount of the single container 200A becomes “state 1”. It can be stored in another container 200 </ b> B whose storage amount is “state 0”. Even when the container 200A has reached the “state 1” level, if the image forming mode is a normal image forming operation, the toner and carrier collected at that time are in the toner ratio. Therefore, the container 200A is continuously accommodated (S25 → S22 to S24).

  After the image forming operation after changing the accommodation destination to another container 200B (forming the special toner image ST) is completed, the accommodation destination is returned to the first container 200A (S26). As a result, when the next image forming mode is other than the toner discharge operation, the storage destination is the first container 200A. However, when the next image forming mode is the toner discharge operation, the storage destination is in the storage amount state 0. It is switched to the second container 200B.

  When it is confirmed in step S21 that the storage amount state of the container 200A is “state 2”, as shown in FIG. 11, the replenishment amount or the number of pixels after the above-described storage amount reaches the set amount L1. The full prediction detection is performed to determine whether or not the 2 count value D2 reaches the third threshold value Z (S37). In this case, the requested image forming operation is executed (S22, S29), and full prediction detection for the container 200A is performed.

  As described above, when the toner T4 of the special toner image ST is stored in the container 200 (A, B) when the storage amount state is “state 1”, the detection of the storage amount of the container 200 is detected as the storage detection. The detection is not performed by the sensor 106 but by prediction detection. As a result, the capacity of the container 200 is reliably detected, and it is accurately detected that the capacity is full. For this reason, the developer (toner and magnetic carrier) overflows from the container 200 (the receiving port 120) when the storage amount is not reliably detected, and the developer in the recovery conveyance device 101 of the recovery system 100. Problems such as clogging will not occur.

  Further, the replenishment time or the number of pixels in the container capacity detection operation and the count value are determined as shown in FIG.

  As shown in FIG. 12, when there is a request for an image forming operation, the control device 7 checks the image forming mode (S40 to S41).

  In this case, when the image forming mode is a mode other than the toner discharge operation (normal image forming operation), the image forming operation for which the replenishment time accumulation unit 14 or the pixel number accumulation unit 13 is requested to measure the replenishment time or the number of pixels. Is performed until the process ends (S42 to S43). After the image forming operation at this time is completed, the accommodation amount state of the container 200 (A, B) is confirmed (S44).

  When the accommodation amount states are “state 0” and “state 1”, the measured count value D is determined as the first count value (cumulative information) D1 (S45). When the accommodation amount state is “state 2”, the measured count value D is determined as the second count value (cumulative information) D2 (S46). The determined count values D1 and D2 are stored (updated) in the storage unit of the replenishment time accumulating unit 14 or the pixel number accumulating unit 13. Each count value D1, D2 is used for subsequent prediction detection (including full prediction detection).

  On the other hand, when the image forming mode is the toner release operation in step S41, the image forming operation in which the replenishment time accumulation unit 14 or the pixel number accumulation unit 13 similarly forms the special toner image ST is completed. (S47 to S48), and after the image forming operation is completed, the count value D at that time is corrected (S49).

  In the correction process, the amount of toner T4 constituting the special toner image ST formed by the toner discharge operation is recovered in the container 200 by the amount of toner and carrier recovered in the container 200 by the normal image forming operation. This is a process of increasing the count value D to compensate for the difference. In the first embodiment, as the correction process, a process of multiplying the count value D by a correction count α consisting of one or more numerical values is performed.

  After the correction process is completed, the container 200 (A, B) is checked for the capacity state (S50). When the capacity states are “state 0” and “state 1”, the container 200 (A, B) is measured. The corrected count value D (= D · α) is determined as the first count value D1 (S51). When the accommodation amount state is “state 2”, the count value D (= D · α) after being measured and corrected is determined as the second count value D2 (S52). The determined count values D1 and D2 are also stored in the storage unit of the replenishment time accumulating unit 14 or the pixel number accumulating unit 13. Each count value D1, D2 is used for subsequent prediction detection (including full prediction detection). By performing the correction process of the count value D, even when an image forming operation related to the toner discharge operation is executed and a prediction detection is performed, the amount of container 200 can be more reliably detected. .

[Embodiment 2]
FIG. 13 shows a main part of the second embodiment. The image forming apparatus 1 according to the second embodiment employs a configuration in which one container 200 is installed as the collection system 100, and the collection operation in the collection system 100 and the detection operation of the container capacity are partially changed. This is the same as the image forming apparatus 1 according to the first embodiment. In other words, the collection system 100 in the image forming apparatus 1 is configured such that the container 200 (without the second container 200B) is installed only with the first container 200A.

  In the image forming apparatus 1, the collection operation in the collection system 100 and the container capacity detection operation are performed as follows. First, as shown in FIG. 13, when there is a request for an image forming operation, the control device 7 checks the container accommodation state (S 60 to S 61).

  In this case, when the storage amount state is “state 0”, the requested image forming operation is executed (S62), and the storage system 100 detects the storage amount of the container 200A by the detection of the storage detection sensor 106A. (S63), and continues until all the image forming operations required at that time are completed (S64). At this time, in the recovery system 100, the recovered toner and carrier are transported to and stored in the container 200A. When the storage capacity state is “state 2”, the above-described full prediction detection (S37 in FIG. 11) is similarly performed (S70).

  When the accommodation amount state is “state 1”, the requested mode of image forming operation is confirmed (S65). In this case, when the image forming mode is a mode other than the “toner releasing operation” described above, that is, a normal image forming operation, the processing operations (S62 to S64) as described above are performed in the same manner.

  On the other hand, when it is determined that the image forming mode is the “toner releasing operation” mode, the toner T4 of the special toner image ST formed by the toner releasing operation is conveyed by the collection system 100, and the toner T4 is stored in the storage amount. Since the container 200A is in the state 2 (that is, the part of the virtual region W), the detection is switched to the prediction detection instead of the detection of the storage detection sensor 106A (S66).

  Subsequently, the image forming operation of the special toner image ST related to the requested toner releasing operation is executed (S67), and the amount of the container 200A contained in the collection system 100 is detected by predictive detection (S68). The process continues until the image forming operation required for (1) is completed (S69). In this case, since the toner T4 of the special toner image ST is stored in the container 200A in the storage amount state 2 by the recovery system 100, the occupation ratio of the toner in the container 200A increases rapidly and the ratio of the magnetic carrier Will drop.

  In the prediction detection at this time, as described above, it is determined whether or not the replenishment operation or the first count value D1 of the number of pixels exceeds the second threshold value Y, and thereby the amount of the container 200A is detected. It will be. At this time, if the first counter value D1 is equal to or greater than the second threshold value Y, the container 200A has reached the set amount L1, so the state is changed to "state 2". The accumulated value of the number of pixels starts to be counted as the second count value D2.

  By performing this predictive detection, regardless of the fact that the collection system 5 has one container and the toner ratio rapidly increases in the virtual region W of the one container 200A, Detection of the capacity of the container 200A is reliably performed.

[Embodiment 3]
FIG. 14 shows a main part of the third embodiment. The image forming apparatus 1 according to the third embodiment is different from the image forming apparatus 1 according to the first embodiment except that the collection system 100 is configured so that the two containers 200 (A, B) are selectively used according to the image forming mode. Is the same. That is, in the image forming apparatus 1, when the image forming mode is an image forming operation other than the toner releasing operation, the collection system 100 stores the toner and the carrier in the first container 200A, and the image forming mode is the toner releasing operation. When in operation, the collection system 100 is configured to accommodate the second container 200B.

  In the image forming apparatus 1, the collection operation in the collection system 100 and the container capacity detection operation are performed as follows. First, as shown in FIG. 14, when there is a request for an image forming operation, the control device 7 checks the type of image forming mode (S80 to S81).

  In this case, when the image forming mode is a mode other than the “toner releasing operation” (normal image forming operation), the storage destination of the toner and carrier recovered by the recovery system 5 is switched to the first container 200A (S82). Specifically, the conveyance direction (FIG. 4) is changed to be sent to the first container 200A by switching the rotation direction of the conveyance member of the fifth conveyance device 150 in the collection system 100.

  Subsequently, the requested image forming operation is executed (S83), and the collection amount of the first container 200A is detected by the collection detection sensor 106A in the collection system 100 (S84). The process continues until all requested image forming operations are completed (S85). At this time, in the recovery system 100, the recovered toner and carrier are transported to and stored in the first container 200A. It should be noted that the detection of the storage amount of the first container 200A is performed by the storage detection sensor 106A, and after the storage detection sensor 106A detects that the storage amount of the container 200A has reached the set amount L1, the first embodiment As in the case of, full prediction detection is performed.

  On the other hand, when the image forming mode is the “toner release operation” mode, the storage destination of the toner and carrier recovered by the recovery system 100 is switched to the second container 200B (S86). Specifically, the conveyance direction (FIG. 4) is changed to be sent to the second container 200B by switching the rotation direction of the conveyance member of the fifth conveyance device 150 in the collection system 100. At this time, the toner T4 of the special toner image ST formed by the toner discharge operation is conveyed by the collection system 100, and the toner T4 is concentrated and stored in the dedicated second container 200B (reversely) Therefore, the detection is switched to the prediction detection instead of the detection by the storage detection sensor 106B (S66).

  Subsequently, the image forming operation of the special toner image ST related to the requested toner releasing operation is executed (S88), and the amount of the second container 200B is detected by the predictive detection in the collection system 100 (S89). These are continued until the image forming operation required at that time is completed (S90). In this case, since the toner T4 of the special toner image ST is exclusively stored in the dedicated second container 200B by the collection system 100, the ratio of the toner in the container 200B accounts for most of the ratio of the magnetic carrier. Very little.

  In the prediction detection at this time, it is determined whether or not the first count value D1 of the replenishment time or the number of pixels exceeds the above-described second threshold value Y (FIG. 6), thereby detecting the storage amount of the container 200B. Will do. In this case, when it is detected that the first count value D1 is less than the second threshold value Y, it is determined that the storage amount of the container 200B has not reached the set amount L1. Further, when it is detected that the first count value D1 is equal to or greater than the second threshold value Y, it is determined that the storage amount of the container 200B has reached the set amount L1, and this is used as a trigger to supply time or the number of pixels. Is started to be counted as the second count value D2. Further, by using the second count value D2, full prediction detection as described above for the container 200B is performed.

  Then, the toner and carrier storage destinations (containers 200A and 200B) are switched according to the image forming mode, and the storage amount detection method for each container 200 (A and B) is selectively used, so that a special toner image for toner discharge operation is obtained. Even if a phenomenon occurs in which the ratio of the toner in the dedicated container 200B for storing the ST toner T4 almost occupies, the amount of the container 200B can be reliably detected.

[Other embodiments]
The image forming apparatus 1 employs a paper transport device that transports the recording paper 9 so as to pass the primary transfer positions of the plurality of image forming devices 20 without using the intermediate transfer device 3, or forms a single color image. You may do. The number of image forming devices 20 can be changed to a single content or a plurality of other contents. In addition, as the collection system 100, a system in which a plurality of three or more containers 200 are installed, or a system in which only one container 200 is set from the beginning (in the case of Embodiment 2) can be adopted. Further, for full prediction detection, for example, a configuration is adopted in which it is determined whether or not the cumulative information (cumulative number) of the number of image formations after the storage amount reaches the set amount L1 exceeds a preset threshold value. You can also

DESCRIPTION OF SYMBOLS 1 ... Image forming apparatus 5 ... Replenishment system (replenishment apparatus)
7: Control device (control means)
9 ... Recording paper (recording medium)
21 ... Photosensitive drum (photoconductor)
22 ... Charging device 23 ... Exposure device 24 ... Developing device 26 ... Drum cleaning device (cleaning device)
29 ... Toner density detection sensor (density detector)
50 ... Developer cartridge (part of replenishing device)
60 ... replenishment device 101 ... collection transport device 106 ... accommodation detection sensor (accommodation detector)
150 ... Fifth transfer device (part of switching mechanism)
154 ... Fifth drive (a part of the switching mechanism)
200A ... first container (container)
200B ... Second container (dedicated container)
T: Toner C ... Magnetic carrier ST ... Special toner image (toner image not transferred to recording medium)
W ... Virtual region L1 ... Setting amount

Claims (6)

A photoreceptor,
A charging device for charging the surface of the photoreceptor;
An exposure apparatus that irradiates light onto the charged surface of the photoconductor to form a latent image;
A developing device that develops the latent image formed on the photoreceptor with a developer containing toner and a magnetic carrier to form a toner image, and a part of the developer is discharged;
A transfer device for finally transferring the toner image formed on the photoreceptor to a recording medium;
A cleaning device that removes at least toner remaining on the surface of the photoreceptor after transfer;
A replenishing device for replenishing the developing device with toner and magnetic carrier constituting the developer;
A container containing at least the toner removed by the developer discharged from the developing device and the cleaning device;
A collecting and conveying device that connects between the developing device and the cleaning device and the container, collects the toner and the magnetic carrier, and conveys the toner and the magnetic carrier to the container;
A storage detector that measures the magnetic permeability of the toner and magnetic carrier stored in the container and detects that the storage amount of the toner and magnetic carrier in the container is equal to or greater than a set amount;
Control means for performing a toner discharge operation for forming a toner image not transferred to the recording medium on the photosensitive member;
Have
A portion where the measurement of the permeability of the storage detector is effective among the containers is set as a virtual region for confirming the necessity of detection by the storage detector,
The control means determines whether an image forming operation to be executed next when the amount of toner and magnetic carrier stored in the container reaches the virtual region is an image forming operation related to the toner releasing operation. In the case where it is determined that the image forming operation is related to the toner discharge operation, the amount of storage is determined based on the replenishment time of the replenishing device or the accumulated information of the number of pixels of the latent image instead of the detection by the storage detector. An image forming apparatus that performs predictive detection for predicting and detecting that the value exceeds a set amount. A plurality of the containers are installed, and a switching mechanism is provided in the collecting and transporting device to transport the toner and the magnetic carrier to any of the plurality of containers and switch the storage destination.
The control means is configured such that when the amount of toner and magnetic carrier accommodated in one of the plurality of containers reaches the virtual area, the presence / absence of another container and the capacity of the other container are greater than or equal to the virtual area. If the other container is present and it is determined that the amount stored in the other container is less than the virtual area, the storage destination in the switching mechanism is determined. The image forming apparatus according to claim 1, wherein the image forming apparatus is switched to another container. When the control means determines that there is no other container in the determination, or if there is another container and the amount of the other container is greater than or equal to the virtual region,
When it is determined that an image forming operation to be executed next is an image forming operation related to the toner discharge operation, the storage destination in the switching mechanism is switched to a container in which the storage amount reaches the virtual region and the prediction detection is performed. The image forming apparatus according to claim 2, wherein:   The image according to any one of claims 1 to 3, wherein the control unit predicts and determines whether or not the storage amount has reached the virtual region based on the replenishment time or accumulated information of the number of pixels. Forming equipment.   The control means performs a correction process to increase the cumulative information of the replenishment time or the number of pixels when an image forming operation related to the toner discharge operation is executed, and based on the cumulative information after the correction process is performed. The image forming apparatus according to claim 1, wherein the prediction detection is performed. A photoreceptor,
A charging device for charging the surface of the photoreceptor;
An exposure apparatus that irradiates light onto the charged surface of the photoconductor to form a latent image;
A developing device that develops the latent image formed on the photoreceptor with a developer containing toner and a magnetic carrier to form a toner image, and a part of the developer is discharged;
A transfer device for finally transferring the toner image formed on the photoreceptor to a recording medium;
A cleaning device that removes at least toner remaining on the surface of the photoreceptor after transfer;
A replenishing device for replenishing the developing device with toner and magnetic carrier constituting the developer;
A plurality of containers containing the developer discharged from the developing device and at least the toner removed by the cleaning device;
A collecting and conveying device that connects between the developing device and the cleaning device and the plurality of containers, collects the toner and the magnetic carrier, and conveys them to the containers;
A switching mechanism that is provided in the collecting and transporting device and transports the toner and the magnetic carrier to any of the plurality of containers to switch the accommodation destination;
A storage detector that measures the magnetic permeability of the toner and magnetic carrier stored in the container and detects that the storage amount of the toner and magnetic carrier in the container is equal to or greater than a set amount;
Control means for performing a toner discharge operation for forming a toner image not transferred to the recording medium on the photosensitive member;
Have
The control means determines whether or not an image forming operation to be executed next is an image forming operation related to the toner discharging operation, and if it is determined that the image forming operation is related to the toner discharging operation, the switching is performed. When the transport destination of the mechanism is switched to a dedicated container selected in advance from among the plurality of containers, and when it is determined that the image forming operation is not related to the toner discharge operation, the transport destination of the switching mechanism is changed to the dedicated container. Switch to a container other than
And about the said exclusive container, performing the prediction detection which estimates and detects that the said accommodation amount became more than a setting amount based on the accumulation information of the replenishment time of the said replenishment apparatus, or the number of pixels of the said latent image. An image forming apparatus.

Images