JP5433551B2 - Image forming apparatus - Google Patents

Description

  The present invention relates to an image forming apparatus such as a copying machine or a printer using an electrophotographic process, and more particularly to control at the time of replacement of a waste toner collecting container that collects and stores residual toner removed from the surface of an image carrier. is there.

  In an image forming apparatus using an electrophotographic system such as a copying machine, a printer, or a FAX, a powder developer (hereinafter referred to as toner) is mainly used, and an electrostatic image formed on an image carrier such as a photosensitive drum. In general, the latent image is visualized with toner in the developing device, and the toner image is transferred directly or via an intermediate transfer member onto a recording medium, and then a fixing process is performed.

  Such an image forming apparatus is equipped with a cleaning device for removing residual toner on the surface of the photosensitive drum and the intermediate transfer member. Conventionally, the residual toner removed by the cleaning device is stored in a waste toner collecting container. Was stored. When the waste toner collection container becomes full, the user is notified and the waste toner collection container is discarded or replaced.

  In this waste toner collection system, every time the waste toner collection container becomes full, the service person or the user has to replace the container, and there is a problem in the operability and usability of the apparatus. In addition, when a large-capacity waste toner collection container is arranged in order to reduce the replacement frequency of the waste toner collection container, there is a problem that the size of the image forming apparatus is increased.

  In view of this, various methods have been proposed to reduce the work burden when replacing the waste toner collection container and to reduce the size of the apparatus. For example, Patent Document 1 discloses a waste toner collection unit that stores waste toner. A configuration integrated with a container is disclosed. According to this configuration, the replacement of the waste toner collection container can be performed at the same time as the replacement of the container, so that the frequency of replacement of the waste toner collection container by the user is reduced and it is not necessary to provide a space for arranging the waste toner collection container.

JP 2006-154259 A

  However, in the configuration in which the waste toner collecting unit is provided in the toner container as in Patent Document 1, the waste toner collecting unit may become full despite the supply toner remaining in the toner container. In this case, it is necessary to replace the toner container with the replenishment toner remaining in the toner container, and there is a problem in that toner is wasted.

  In particular, when an image with a low printing rate is frequently printed, a developing device is used because there is little toner used for development by flying from the developer carrying member (developing roller) to the electrostatic latent image carrying member (photosensitive drum). The toner particles in the toner particles are hardly replaced, the toner is excessively charged, and image density reduction and fogging may occur. Therefore, a method is adopted in which the deteriorated toner on the developer carrying member is forcibly discharged so that the deteriorated toner is not used for image formation. In this case, since the amount of waste toner collected with respect to the amount of toner replenished from the toner container to the developing device increases, the waste toner collection unit in the toner container tends to become full.

On the other hand, in order to prevent the phenomenon that the waste toner collection unit becomes full when the replenishment toner remains in the toner container, the waste toner collection unit also needs to secure a volume corresponding to that. It leads to enlargement. When the size of the toner container is increased, space saving in the image forming apparatus is hindered, and the amount of resin forming the toner container increases, so that the environmental load when the toner container is discarded increases. Further, even in a configuration having a means for compressing waste toner in the waste toner collection unit as in Patent Document 1, a certain initial volume is required, and the structure of the toner container is complicated.

  SUMMARY OF THE INVENTION In view of the above problems, the present invention provides an image forming apparatus capable of continuously using a toner container even when a waste toner collecting unit in the toner container is full, and reducing a user's work load as much as possible. The purpose is to provide.

  In order to achieve the above object, the present invention provides an image carrier that carries a toner image, a cleaning unit that removes residual toner on the image carrier, and a new toner image for forming a toner image on the toner carrier. A detachable toner container having a toner container for storing toner, and a waste toner collecting part for storing waste toner removed by the cleaning unit; and connected to the toner container and the cleaning unit; Waste toner transfer means for transferring the waste toner removed by the cleaning means to the waste toner collection unit, a buffer container provided in the middle of the waste toner transfer means for temporarily storing waste toner, and the waste toner First full detection means for detecting the fullness of the recovery unit, and control means for controlling the driving of the waste toner transfer means according to the detection result of the first full detection means. The control means stores the waste toner in the waste toner collection section until the first full detection means detects that the waste toner collection section is full, and when the waste toner collection section is detected full, When the transfer of the waste toner from the buffer container to the waste toner collecting unit is stopped and the waste toner is stored in the buffer container, and the toner container is replaced while the waste toner is stored in the buffer container, An image forming apparatus that transfers waste toner from the buffer container to the waste toner collecting unit.

  According to the present invention, in the image forming apparatus configured as described above, the buffer container is detachable from the main body of the image forming apparatus, and is provided with a second fullness detecting means for detecting the fullness of the buffer container. It is said.

  According to the present invention, in the image forming apparatus having the above configuration, the capacity of the waste toner collecting unit is larger than an average value of the amount of waste toner collected when all of the toner contained in the toner containing unit is consumed. It is characterized by.

  According to another aspect of the present invention, in the image forming apparatus having the above-described configuration, a toner remaining amount detecting unit that detects a remaining amount of toner in the toner storage unit, and a notification unit that notifies whether the toner container and the buffer container need to be replaced. And the control means stops the printing operation and uses the notification means when it detects that the waste toner collecting section and the buffer container are full in a state where toner remains in the toner storage section. And a notification requesting replacement of the buffer container.

  According to the present invention, in the image forming apparatus configured as described above, when the control unit detects that the waste toner collection unit and the buffer container are full in a state where the toner in the toner storage unit is empty, a printing operation is performed. The information processing apparatus is characterized in that, while stopping, a notification requesting replacement of at least one of the buffer container and the toner container is performed using the notification means.

  According to the first configuration of the present invention, since the waste toner is stored in the buffer container when the waste toner collection unit in the toner container is full, the toner is stored even after the waste toner collection unit is full. Printing can be continued until the toner in the container is used up. In addition, since the capacity of the waste toner collecting unit can be reduced, it is advantageous for downsizing and space saving of the image forming apparatus, and the resin material for forming the toner container is reduced, and the environment when the toner container is discarded. The load can also be reduced. Further, when the toner container is replaced while the waste toner is stored in the buffer container, the waste toner collecting unit is filled before the buffer container by transferring the waste toner from the buffer container to the waste toner collecting unit. Thus, the waste toner collecting unit always stores the waste toner until it is full, and the capacity of the waste toner collecting unit can be used effectively.

  According to the second configuration of the present invention, in the image forming apparatus having the first configuration, the second fullness detection for detecting whether the buffer container is full and making the buffer container detachable from the image forming apparatus main body. By providing the means, when the buffer container is full, the buffer container can be replaced so that the buffer container can be reduced in size and the buffer container can be prevented from overflowing.

  According to the third configuration of the present invention, in the image forming apparatus having the second configuration, the waste toner collecting unit has a capacity that is collected when all of the toner contained in the toner containing unit is consumed. By making it larger than the average value of the toner amount, there is usually no possibility that waste toner is accumulated in the buffer container, and there is almost no need to replace the buffer container, thereby further reducing the work burden on the user.

  Further, according to the fourth configuration of the present invention, in the image forming apparatus having the second or third configuration, the waste toner collection unit and the buffer container are full with the toner remaining in the toner storage unit. At this time, since the printing operation is stopped and a notification for requesting replacement of the buffer container is made using the notification means, it is possible to prevent the toner container from being replaced while the toner remains in the toner container. Can do.

  According to the fifth configuration of the present invention, in the image forming apparatus having the fourth configuration, when the waste toner collection unit and the buffer container are full with the toner in the toner storage unit being empty. The printing operation is stopped and the notification means is used to notify the request to replace at least one of the buffer container and the toner container. For example, when the toner remains in the developing device, only the buffer container is replaced. By doing so, printing can be resumed. When the remaining amount of toner in the developing device is low, printing can be resumed by replacing only the toner container or both the toner container and the buffer container.

1 is a schematic cross-sectional view illustrating a configuration of an image forming apparatus according to an embodiment of the present invention. FIG. 3 is a schematic view showing a transfer path of waste toner in the image forming apparatus of the present invention. FIG. 3 is a block diagram for explaining a control path of the image forming apparatus of the present invention. The figure which shows the structural example of the message storage table used for the image forming apparatus of this invention. 6 is a flowchart showing a waste toner transfer procedure in the image forming apparatus of the present invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a schematic sectional view of an image forming apparatus provided with the developing device of the present invention. In an image forming apparatus (for example, a monochrome printer) 100, when a printing operation is performed, an electrostatic latent image based on original image data transmitted from a personal computer (PC) (not shown) is exposed at an image forming unit P in the apparatus main body. A toner image is formed on the body drum (image carrier) 1 where toner is attached to a portion where the potential of the electrostatic latent image is reduced by the developing device 4. The toner is supplied to the developing device 4 from a toner container (toner container) 5. In such an image forming apparatus 100, the image forming process for the photosensitive drum 1 is executed while rotating the photosensitive drum 1 clockwise in FIG.

  The image forming unit P includes a charging unit 2, an exposure unit 3, a developing device 4, a transfer roller 6, a cleaning device 7, and a charge removal device (not shown) along the rotation direction (clockwise) of the photosensitive drum 1. Is arranged. The photosensitive drum 1 is formed, for example, by laminating a photosensitive layer on an aluminum drum, and the charging unit 2 charges the surface. Then, an electrostatic latent image in which the charged charges are attenuated is formed on the surface that has received a laser beam from the exposure unit 3 described later. The photosensitive layer is not particularly limited. For example, amorphous silicon (a-Si) having excellent durability, or an organic photosensitive layer (OPC) that generates high-resolution images with little generation of ozone during charging. Etc.) are preferred.

  The charging unit 2 uniformly charges the surface of the photosensitive drum 1. For example, a corona discharge device that discharges by applying a high voltage using a thin wire or the like as an electrode is used as the charging unit 2. Instead of the corona discharge device, a contact-type charging device that applies a voltage to the charging member while a charging member typified by a charging roller is in contact with the surface of the photoreceptor may be used. The exposure unit 3 irradiates the photosensitive drum 1 with a light beam (for example, a laser beam) based on the image data, and forms an electrostatic latent image on the surface of the photosensitive drum 1.

  The developing device 4 forms toner images by attaching toner to the electrostatic latent image formed on the photosensitive drum 1. Here, a single-component developer (hereinafter also simply referred to as toner) composed only of magnetic toner components is accommodated in the developing device 4. The transfer roller 6 transfers the toner image formed on the surface of the photosensitive drum 1 to the sheet conveyed through the sheet conveyance path 11 without disturbing the toner image. The cleaning device 7 includes a cleaning roller, a blade material, and the like that are in linear contact with the longitudinal direction of the photosensitive drum 1, and removes residual toner remaining on the surface of the photosensitive drum 1 after the toner image is transferred to the paper. To do.

  Then, the exposure unit 3 emits a laser beam (light beam) on the photosensitive drum 1 based on image data inputted in advance, thereby forming an electrostatic latent image based on the image data on the surface of the photosensitive drum 1. Thereafter, the developing device 4 attaches toner to the electrostatic latent image to form a toner image.

  A sheet is conveyed from the sheet storage unit 10 through the sheet conveyance path 11 and the registration roller pair 13 at a predetermined timing toward the image forming unit P on which the toner image is formed as described above. The toner image on the surface of the photosensitive drum 1 is transferred onto the sheet by the transfer roller 6. The sheet on which the toner image has been transferred is separated from the photosensitive drum 1, conveyed to the fixing unit 8, and heated and pressurized to fix the toner image on the sheet. The paper that has passed through the fixing unit 8 passes through the discharge roller pair 14 and is discharged to the paper discharge unit 15.

  FIG. 2 is a schematic view showing a waste toner transfer path in the image forming apparatus of the present invention. The cleaning device 7 includes a rubbing roller 16 and a cleaning blade 17. The rubbing roller 16 is pressed against the photoconductive drum 1 with a predetermined pressure, and is driven to rotate in the same direction as the photoconductive drum 1 on the contact surface with the photoconductive drum 1 by a driving means (not shown).

  A cleaning blade 17 is fixed in contact with the photosensitive drum 1 on the surface of the photosensitive drum 1 downstream of the contact surface with the rubbing roller 16 in the rotation direction. The material, hardness and dimensions of the cleaning blade 17, the amount of biting into the photosensitive drum 1, the pressure contact force, and the like are appropriately set according to the specifications of the photosensitive drum 1.

  The waste toner collected from the photosensitive drum 1 by the cleaning device (cleaning means) 7 is stored in the toner container 5 via the buffer container 20. A first waste toner transfer pipe 21 is connected between the cleaning device 7 and the buffer container 20, and a second waste toner transfer pipe 22 is connected between the buffer container 20 and the toner container. In the first waste toner transfer pipe 21 and the second waste toner transfer pipe 22, a first spiral 23a and a second spiral 23b are rotatably arranged by a spiral drive motor 31 (see FIG. 3), respectively. The first waste toner transfer pipe 21, the second waste toner transfer pipe 22, the first spiral 23a, and the second spiral 23b constitute waste toner transfer means for transferring the waste toner removed by the cleaning device 7 to the toner container 5. To do.

  The toner container 5 is partitioned into a toner storage unit 24a that stores new toner supplied to the developing device 4 and a waste toner collection unit 24b that stores waste toner transferred from the buffer container 20, A second waste toner transfer pipe 22 is connected to the waste toner collecting section 24b.

  Further, a first full detection sensor 25 for detecting whether or not the amount of waste toner stored in the waste toner collecting unit 24b is full is provided in the vicinity of the toner container 5, and in the vicinity of the buffer container 20. Is provided with a second full detection sensor 27 for detecting whether or not the amount of waste toner stored in the buffer container 20 is full. The types of the first full detection sensor 25 and the second full detection sensor 27 are not particularly limited, but since the toner container 5 and the buffer container 20 are consumables that are discarded and replaced, the amount of waste toner can be detected from the outside of the container. Is preferred. For example, there is a method of detecting a change in magnetic permeability with an increase in the amount of waste toner with a magnetic permeability sensor. In the case of the second fullness detection sensor 27, the buffer container 20 is placed on a swingable pedestal, and the swing of the pedestal due to the weight change of the buffer container 20 is detected using a PI (photo interrupter) sensor. And the like.

  In order to effectively use the capacity of the waste toner collecting unit 24b and the buffer container 20, the first full detection sensor 25 and the second full detection sensor 27 are configured so that the waste toner is collected in the waste toner collecting unit 24b and the buffer container 20 without a gap. It is necessary to detect the filled state. Therefore, for example, when the first full detection sensor 25 and the second full detection sensor 27 are magnetic permeability sensors, as shown in FIG. 2, the first full detection sensor 25 is disposed opposite to the upper portion of the waste toner collecting unit 24b, and the second The fullness detection sensor 27 is preferably disposed on the upper side of the side opposite to the side of the buffer container 20 to which the first waste toner transfer pipe 21 is connected (the left side surface of the buffer container 20 in FIG. 2).

  A toner remaining amount sensor 29 is disposed in the developing device 4. As the toner remaining amount sensor 29, a magnetic permeability sensor that detects the magnetic permeability of toner in the developing device 4 is used. In this embodiment, the toner remaining amount sensor 29 detects the magnetic permeability of the toner and outputs a voltage value corresponding to the detection result to a control unit 90 (see FIG. 3) described later. 90, the remaining amount of toner is determined from the output value of the remaining toner sensor 29. The sensor output value changes in accordance with the remaining amount of toner, and the output value increases as the remaining amount of magnetic toner increases, and the output value decreases as the remaining amount of toner decreases. The control unit 90 transmits a control signal to the toner supply motor 33 (see FIG. 3) according to the determined remaining toner amount, drives the toner supply roller 5a of the toner container 5 for a predetermined time, and places it in the developing device 4. Supply a fixed amount of toner.

  As the toner remaining amount sensor 29, in addition to the above-described magnetic permeability sensor, a piezoelectric sensor that takes out as an electric signal that pressure has been applied to the detection surface, a detection filler that rotates by the pressure of the toner, and a rotation of the detection filler. It is also possible to use an optical sensor having a detection sensor (photo interrupter) that detects that the optical path is opened or closed by movement.

  FIG. 3 is a block diagram for explaining a control path of the image forming apparatus of the present invention. Portions common to FIG. 1 are denoted by the same reference numerals and description thereof is omitted. In addition, since various controls of each part of the apparatus are performed when the image forming apparatus 100 is used, the control means of the entire image forming apparatus 100 is complicated. Therefore, here, the portions necessary for switching the transfer of the waste toner to the toner container 5 and the buffer container 20 and for controlling the notification of the replacement timing of the toner container 5 and the buffer container 20 will be mainly described. Further, the description of the parts that have already been described is omitted or simplified.

  The control unit 90 includes a central processing unit (CPU) 91 as a central processing unit, a read only memory (ROM) 92 that is a read-only storage unit, a random access memory (RAM) 93 that is a readable / writable storage unit, A plurality of (here, two) I / Fs 95 that transmit control signals to each device in the image forming apparatus 100 and receive input signals from the operation unit 50. At least.

  The ROM 92 stores a control program for the image forming apparatus 100, data necessary for control, and the like that are not changed during use of the image forming apparatus 100. The RAM 93 stores necessary data generated during the control of the image forming apparatus 100, data temporarily required for controlling the image forming apparatus 100, and the like. The ROM 92 (or RAM 93) is provided with a message storage table for storing a plurality of messages for each state of the toner container 5 or the buffer container 20.

  A configuration example of the message storage table is shown in FIG. In the message storage table, various character messages corresponding to the state of the apparatus are stored as data. Here, three types of message data of exchange indications 1 to 3 urging the exchange work by the user are stored. The CPU 91 selects message data based on detection signals from the second fullness detection sensor 27 and the toner remaining amount sensor 29 and displays it on the liquid crystal display unit 51 in the operation unit 50.

  For example, when the second full detection sensor 27 detects that the buffer container 20 is full, the message “Replace buffer container” (replacement display 1) requesting the user to replace the buffer container 20 is selected. Is done. In addition, when the toner remaining level in the developing device 4 detected by the toner remaining amount sensor 29 is equal to or less than the predetermined value L1, the toner in the toner container 5 has become empty, but the developing device 4 Since the toner still remains, image formation is possible for a while. Therefore, the message (replacement display 2) “Toner is low. It is recommended to replace the toner container.” Is selected.

  When the remaining toner level in the developing device 4 is equal to or lower than the predetermined value L2 (L1> L2), the remaining toner in the developing device 4 is almost gone. Accordingly, a message (replacement display 3) of “Toner is out. Please replace the toner container” requesting replacement of the toner container 5 is selected.

  In addition, the control unit 90 transmits a control signal from the CPU 91 to the respective units and apparatuses in the image forming apparatus 100 through the I / F 95. In addition, a signal indicating the state and an input signal are transmitted from each part or device to the CPU 91 through the I / F 95. For example, detection signals from the first full detection sensor 25, the second full detection sensor 27, and the toner remaining amount sensor 29 are transmitted to the CPU 91 in the control unit 90 via the I / F (interface) 95. The contents of waste toner recovery switching control to the buffer container 20 and the toner container 5 will be described later.

  The operation unit 50 is provided with a liquid crystal display unit 51 and an LED 52 indicating various states, and displays the state of the printer 100 and displays the image forming status and the number of copies to be printed. Various settings of the printer 100 are performed from a printer driver of a personal computer.

  In addition, the operation unit 50 includes a start button for instructing the user to start image formation, a stop / clear button used when the image formation is stopped, and various settings of the image forming apparatus 100 in a default state. A reset button or the like is provided for use.

  The spiral drive motor 31 transports waste toner from the cleaning device 7 to the buffer container 20 according to a control signal from the control unit 90, and transports waste toner from the buffer container 20 to the waste toner collecting unit 24b of the toner container 5. The second spiral 23a is driven to rotate independently. The second spiral 23b is connected to the spiral drive motor 31 via the clutch 32. By connecting or disconnecting the clutch 32, the second spiral 23b can be rotated or stopped independently of the first spiral 23a. ing.

  FIG. 5 is a flowchart showing a waste toner transfer procedure of the image forming apparatus of the present invention. With reference to FIGS. 1 to 4, the control at the time of collecting waste toner to the buffer container 20 and the toner container 5 will be described according to the steps of FIG. 5.

  When printing is started by the user (step S1), the first spiral 23a is rotationally driven by the spiral drive motor 31. Next, it is detected by the first full detection sensor 25 whether or not the waste toner collection unit 24b is full (step S2). When the waste toner collecting unit 24b is not full, the second spiral 23b is rotated together with the first spiral 23a (step S3). Thus, the waste toner collected from the photosensitive drum 1 by the cleaning device 7 is collected by the waste toner collecting unit 24b via the buffer container 20.

  When the waste toner collecting unit 24b becomes full, the control unit 90 transmits a control signal to the spiral drive motor 31, and stops the rotation of the second spiral 23b by disconnecting the clutch 32 (step S4). Since the first spiral 23 a is continuously driven to rotate, the waste toner is stored in the buffer container 20.

  Next, it is detected by the second full detection sensor 27 whether or not the buffer container 20 is full (step S5). When the buffer container 20 is not full, the waste toner is continuously stored in the buffer container 20 by the rotation of the first spiral 23a. Then, it is determined whether or not printing has been completed (step S6). If printing has been completed, the driving of the image forming apparatus 100 is stopped and the process is terminated. If printing is continuing, the process returns to step S2 to continue the printing operation. On the other hand, when it is detected in step S5 that the buffer container 20 is full, the control unit 90 forcibly terminates printing and stops driving the image forming apparatus 100 (step S7).

  During the printing operation, the toner supply motor 33 is driven according to the toner remaining amount level in the developing device 4 detected by the toner remaining amount sensor 29, and new toner is supplied from the toner storage portion 24a of the toner container 5 to the developing device. 4 is supplied. When the toner in the toner container 5 becomes empty, the supply of toner from the toner container 5 to the developing device 4 is stopped, so that the toner remaining level in the developing device 4 starts to decrease.

  Therefore, simultaneously with the stop of the printing operation in step S7 or subsequent to the stop of the printing operation, the control unit 90 (CPU 91) determines whether or not the remaining toner level in the developing device 4 is equal to or less than L1 (step S7). Step S8). When the remaining toner level exceeds L1, it is inefficient to replace the toner container 5 because unused toner remains in the toner container 24a. Therefore, the exchange display 1 for requesting the exchange of the buffer container 20 is selected from the message storage table and displayed on the liquid crystal display unit 51 (step S9).

  If the remaining toner level is not more than L1, it is further determined whether or not the remaining toner level is not more than L2 (step S10). When the remaining toner level is higher than L2, the toner in the toner container 24a of the toner container 5 is emptied, but the toner still remains in the developing device 4, and image formation is not performed for a while. Is possible. Therefore, the replacement display 1 for requesting replacement of the buffer container 20 and the replacement display 2 for prompting replacement of the toner container 5 are selected from the message storage table and displayed on the liquid crystal display unit 51 (step S11).

  If the remaining toner level is equal to or lower than L2 in step S10, the replacement display 3 for requesting replacement of the toner container 5 is selected from the message storage table and displayed on the liquid crystal display unit 51 (step S12).

  When the replacement display 1 is displayed (step S9) or when the replacement displays 1 and 2 are displayed (step S11), it is determined whether the toner container 5 or the buffer container 20 has been replaced (step S11). S13) When at least one of the toner container 5 and the buffer container 20 is replaced, the process returns to step S2 and printing is resumed.

  For example, when only the buffer container 20 is replaced, the waste toner collecting unit 24b of the toner container 5 remains full, so that the buffer container is kept in a state where the second spiral 23b is stopped by continuing the disengagement state of the clutch 32. The waste toner is stored at 20 (steps S 2 → S 4 → S 5 → S 2). When the toner container 5 is also exchanged together with the buffer container 20, the waste toner collected from the photosensitive drum 1 by the cleaning device 7 is immediately collected by the waste toner collecting unit 24b via the buffer container 20 (Step S2 → S3 → S2).

  When only the toner container 5 is replaced without replacing the buffer container 20, the second spiral 23 b is driven to rotate by putting the clutch 32 in the connected state, and the replacement of the toner container 5 from the buffer container 20 is performed. The waste toner is transferred to the waste toner collecting unit 24b (steps S2 → S3 → S2). In this case, since the waste toner in the buffer container 20 is reduced, the full state of the buffer container 20 is eliminated.

  On the other hand, if the replacement display 3 is displayed (step S12), it is determined whether or not the toner container 5 has been replaced (step S14). If the toner container 5 has been replaced, the process returns to step S2 and printing resumes. At the same time, the second spiral 23b is driven to rotate by setting the clutch 32 in the connected state, and the waste toner is transferred from the buffer container 20 to the waste toner collecting portion 24b of the replaced toner container 5 (step S2). → S3 → S2). In this case, since the waste toner in the buffer container 20 is reduced, the full state of the buffer container 20 is eliminated.

  Although not shown in the flowchart of FIG. 5, in step S <b> 12, a display prompting replacement of the buffer container 20 may be performed together with the replacement display 3. When such a display is performed and the buffer container 20 is also replaced with the toner container 5, the waste toner collected from the photosensitive drum 1 by the cleaning device 7 is immediately sent to the waste toner collecting unit 24 b via the buffer container 20. It is collected (steps S2 → S3 → S2).

  The remaining toner sensor 29 constantly detects the remaining amount of toner in the toner container 24a of the toner container 5 based on the remaining toner level in the developing device 4, and is printing (steps S2 → S3 → S2, Alternatively, if the remaining toner level in the developing device 4 becomes equal to or less than the predetermined value L1 in steps S2 → S4 → S5 → S2), the replacement display 2 recommending replacement of the toner container 5 is displayed on the liquid crystal display unit 51. If the remaining toner level in the developing device 4 during printing is less than or equal to the predetermined value L2, the liquid crystal display unit displays a replacement display 3 for stopping the driving of the image forming apparatus 100 and requesting replacement of the toner container 5. 51.

  By performing the above-described control, when the waste toner collecting unit 24b becomes full with toner remaining in the toner storage unit 24a of the toner container 5, the waste toner is stored in the buffer container 20. Thereby, even after the waste toner collecting unit 24b is full, printing can be continued until the toner in the toner containing unit 24a is used up. Further, since the capacity of the waste toner collecting unit 24b can be reduced, the resin material for forming the toner container 5 is also reduced, and the environmental load when the toner container is discarded can be reduced.

  Further, since the buffer container 20 is connected to the cleaning device 7 and the toner container 5 via the first waste toner transfer pipe 21 and the second waste toner transfer pipe 22, the buffer container 20 can be freely arranged in the empty space of the image forming apparatus 100. Can do.

  The capacity of the waste toner collection unit 24b of the toner container 5 is set slightly larger than the average value of the amount of waste toner collected when the toner stored in the toner storage unit 24a is consumed. In this way, accumulation of waste toner in the buffer container 20 does not normally occur.

  If a user who frequently prints at a low printing rate and the number of discharges of deteriorated toner increases, the actual amount of waste toner exceeds the capacity of the waste toner collecting unit 24b, and the toner container 5 is replaced. A slight amount of waste toner is accumulated in the buffer container 20. However, when the toner container 5 is replaced, the waste toner remaining in the buffer container 20 is transferred to the waste toner collecting unit 24b. Therefore, the waste toner is accumulated in the buffer container 20 because of low printing rate printing. Only when the ratio is very high. Therefore, if the capacity of the buffer container 20 is increased to some extent, it is almost unnecessary to replace the buffer container 20.

  On the other hand, when the second fullness detection sensor 27 is provided as in the above embodiment, the capacity of the buffer container 20 can be reduced, so that the buffer container 20 needs to be replaced when the ratio of printing at a low printing rate is very large. However, the image forming apparatus 100 can contribute to downsizing and space saving.

  In addition, the present invention is not limited to the above embodiments, and various modifications can be made without departing from the spirit of the present invention. For example, in the above-described embodiment, whether or not toner remains in the toner container 24a of the toner container 5 based on the toner remaining amount level in the developing device 4 detected by the toner remaining amount sensor 29 in the developing device 4 is determined. However, for example, it may be configured to directly detect the remaining amount of toner in the toner storage unit 24a. In that case, it can also be determined whether toner remains in the toner storage portion 24a based on the amount of toner replenished from the toner container 5 to the developing device 4 (integrated rotation speed of the toner supply motor 33). It is also possible to determine whether toner remains in the toner container 24a by using a method such as calculating the number of dots printed and the amount of toner used based on the number of printed dots.

  In the above-described embodiment, the case of using a one-component developer composed only of a magnetic toner component has been described as an example. However, even when a two-component developer including a magnetic carrier and a non-magnetic toner is used. It can be applied in exactly the same way.

  In the above-described embodiment, a character message is displayed on the liquid crystal display unit 51 of the operation unit 50 to notify the replacement timing of the buffer container 20 and the toner container 5. However, for example, a voice message is used instead of the character message data. The message data may be stored in the message storage table and notified using the voice message selected by the control unit 90.

  Further, the present invention is not limited to the monochrome printer as shown in FIG. 1, but a waste toner collecting mechanism such as a tandem or rotary type color copier and printer, a monochrome copier, a digital multifunction machine, a facsimile machine, etc. Of course, the present invention can be applied to various image forming apparatuses having the above. For example, in the case of a color image forming apparatus, the waste toner collected from the photosensitive drum and the waste toner collected from the intermediate transfer member (toner carrier) are collected into the toner containers of each color through the buffer container. What is necessary is just to control to transfer to a part.

  Further, in the above embodiment, the toner container 5 is used as a waste toner collecting container. However, when a developing cartridge in which the developing device and the toner container are integrated is used, the waste toner container in the developing cartridge is used as the waste toner in the above embodiment. It corresponds to the collection unit 24b. In a process cartridge having a photosensitive drum, a charging unit, and a developing unit, the waste toner collecting unit corresponds to the waste toner collecting unit 24b of the above embodiment.

  INDUSTRIAL APPLICABILITY The present invention can be used for an image forming apparatus that collects residual toner removed from the surface of a toner carrier and stores it in a toner container. A toner container having a waste toner collecting unit for storing toner and a buffer container for temporarily storing the waste toner are provided, and the waste toner is stored in the waste toner collecting unit until it is detected that the waste toner collecting unit is full. When the waste toner collecting unit is detected to be full, the transfer of the waste toner from the buffer container to the waste toner collecting unit is stopped and the waste toner is stored in the buffer container.

  Thereby, even if the waste toner collecting part of the toner container becomes full during printing, the replacement of the toner container can be postponed and printing can be continued. Accordingly, the toner in the toner storage unit can be used efficiently and the capacity of the waste toner recovery unit can be reduced. Therefore, it is possible to provide an image forming apparatus that reduces the work burden on the user and saves space.

1 Photosensitive drum (image carrier)
4 Developing device 5 Toner container (toner container)
7 Cleaning device (cleaning means)
20 Buffer container 21 First waste toner transfer pipe (waste toner transfer means)
22 Second waste toner transfer pipe (waste toner transfer means)
23a First spiral (waste toner transfer means)
23b Second spiral (waste toner transfer means)
24a Toner storage unit 24b Waste toner collection unit 25 First full detection sensor 27 Second full detection sensor 29 Toner remaining amount sensor (toner remaining amount detecting means)
31 Spiral drive motor 33 Toner supply motor 50 Operation section 51 Liquid crystal display section (notification means)
90 Control unit (control means)
100 Image forming apparatus P Image forming unit

Claims (3)

An image carrier for carrying a toner image;
Cleaning means for removing residual toner on the image carrier;
A detachable toner container having a toner container for storing new toner for forming a toner image on the toner carrier, and a waste toner collecting part for storing the waste toner removed by the cleaning means; ,
Waste toner transfer means connected to the toner container and the cleaning means, for transferring waste toner removed by the cleaning means to the waste toner collecting section;
A buffer container which is provided in the middle of the waste toner transfer means and is detachable from the image forming apparatus main body for temporarily storing waste toner;
First full detection means for detecting fullness of the waste toner recovery unit;
Second full detection means for detecting fullness of the buffer container;
A toner remaining amount detecting means for detecting the remaining amount of toner in the toner containing portion;
Notification means for notifying whether or not the toner container and the buffer container need to be replaced;
And a control means for controlling driving of the waste toner transport means in accordance with a detection result of the first full state detection means and the second full state detection means,
The control means stores the waste toner in the waste toner collection section until the first full detection means detects that the waste toner collection section is full, and the buffer is detected when the waste toner collection section is detected full. When the transfer of the waste toner from the container to the waste toner collecting unit is stopped and the waste toner is stored in the buffer container, and the toner container is replaced while the waste toner is stored in the buffer container, While transferring waste toner from the buffer container to the waste toner recovery unit ,
When it is detected that the waste toner collecting unit and the buffer container are full while toner remains in the toner storage unit, a printing operation is stopped and a notification requesting replacement of the buffer container is made using the notification unit. image forming apparatus and performs. The image forming apparatus according to claim 1 , wherein a capacity of the waste toner collecting unit is larger than an average value of the amount of waste toner collected when all of the toner contained in the toner containing unit is consumed. . The control means stops a printing operation and detects the buffer container and the buffer container using the notification means when the waste toner collecting part and the buffer container are full when the toner in the toner containing part is empty. The image forming apparatus according to claim 1, wherein a notification requesting replacement of at least one of the toner containers is made .

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