JP5852897B2 - Image forming apparatus - Google Patents

Description

  The present invention relates to an image forming apparatus.

  In an electrophotographic image forming apparatus, an electrostatic latent image is formed on the surface of a photosensitive member by a charging device and an exposure device, and toner is supplied by a developing device to develop the electrostatic latent image into a toner image. The image is transferred to a recording medium such as recording paper, and the toner image is fixed on the recording paper by a fixing device, thereby forming an image.

  Patent Document 1 describes an electrophotographic image forming apparatus that forms a color image using toners of four colors of black, cyan, magenta, and yellow. This image forming apparatus includes four photoconductors and developing devices corresponding to four colors, and transfers (primary transfer) toner images formed on each photoconductor to an intermediate transfer belt, The superimposed toner image is transferred (secondary transfer) to a recording medium to form a color image.

  The image forming apparatus described in Patent Document 1 includes a collection container for collecting the toner (waste toner) remaining on the photoconductor after the primary transfer, corresponding to each photoconductor. The image forming apparatus also includes one collection container for collecting toner (waste toner) remaining on the intermediate transfer belt after the secondary transfer. That is, this image forming apparatus includes five collection containers for collecting waste toner. Each of these collection containers is provided with a sensor for detecting whether or not the collection containers are full. When the collection containers are full, the user needs to replace the collection containers. Accordingly, when a large number of collection containers are provided as in the image forming apparatus described in Patent Document 1, it is necessary for the user to replace each collection container individually, which increases labor.

  Patent Document 2 describes an image forming apparatus for solving such a problem. Specifically, the image forming apparatus includes two recovery containers for recovering waste toner on the intermediate transfer belt, and one of the two recovery containers is replaceable, and the other is It is provided in a dead space in the image forming apparatus. The image forming apparatus is configured such that when the other collection container is full, waste toner that cannot be contained in the other collection container enters one collection container.

  Therefore, in the image forming apparatus described in Patent Document 2, the capacity for collecting the waste toner on the intermediate transfer belt is larger than that of the conventional one, and the number of times of exchanging the collection container is reduced, thereby reducing the labor of the user. Can do. The image forming apparatus is configured such that when one of the two collection containers becomes full, waste toner enters one of the collection containers. Therefore, whether or not the other collection container is full. There is an advantage that it is not necessary to provide a sensor for detecting this.

JP 2004-279919 A JP 2011-128552 A

  In the image forming apparatus described in Patent Document 2, the second collection container is provided in the dead space in the image forming apparatus. However, when there is no or small dead space, the second collection container is not provided. Can not. In addition, in the image forming apparatus described in Patent Document 2, it is not possible to reduce the user's effort in replacing each collection container for collecting the waste toner on the photoconductor. Furthermore, each recovery container for recovering the waste toner on the photosensitive member must be provided with a sensor for detecting whether or not it is full.

  SUMMARY An advantage of some aspects of the invention is to provide an image forming apparatus capable of reducing the number of parts and reducing a user's trouble in replacing a container for collecting waste toner. For the purpose.

The present invention relates to an image forming apparatus for transferring a toner image formed on a photoreceptor by a developing device to a recording medium via an intermediate transfer belt and forming an image on the recording medium.
A toner supply device for supplying toner to the developing device;
A first collection container provided integrally with the toner replenishing device and collecting waste toner;
A first guide path that communicates with the first recovery container and guides the waste toner on the photoreceptor to the first recovery container;
A second guide path communicating with the first recovery container and guiding waste toner on the intermediate transfer belt to the first recovery container;
A second collection container that communicates with the first collection container and collects waste toner overflowing from the first collection container;
A first detector for detecting whether toner remains in the toner replenishing device;
A first notification unit for notifying that it is time to replace the toner supply device and the first collection container when no toner remains in the toner supply device;
A second detector for detecting whether or not the inside of the second collection container is full of waste toner;
An image forming apparatus comprising: a second notification unit that notifies that it is time to replace the second collection container when the second collection container is full of waste toner.

  According to the present invention, the toner replenishing device is a color toner replenishing device that replenishes color toner.

  Further, according to the present invention, in the second guide path, a communication portion between the second guide path and the first recovery container is directly above a communication portion between the first guide path and the first recovery container. It is provided so that it may be located.

In the present invention, the first collection container is
An upper part of the recovery container that communicates with the first guide path and the second guide path, and a lower part of the recovery container that is positioned vertically below the upper part of the recovery container and communicates with the second recovery container. Including
A cross-sectional area perpendicular to the vertical direction of the upper part of the recovery container is provided to be smaller than a cross-sectional area perpendicular to the vertical direction of the lower part of the recovery container.

  According to the present invention, since the toner replenishing device for replenishing toner and the first collection container for collecting waste toner are integrated, it is not necessary to replace them individually, and the detection result of the first detection unit is obtained. When it is informed that it is time to exchange, these can be exchanged at the same time, and the user's effort can be reduced. In addition, when the first collection container is full of waste toner, the waste toner that does not fit in the first collection container can be collected in the second collection container and replaced based on the detection result of the second detection unit. When it is notified that it is time, the second collection container can be replaced. Further, since the first recovery container does not need a sensor for detecting that the waste toner is full, the number of parts can be reduced.

  According to the invention, the toner replenishing device is a color toner replenishing device that replenishes color toner. In the case of color toner, it is generally used less frequently than black toner, and it takes time until the toner in the toner replenishing device is used up. As a result, the color toner collected in the second collection container is less likely to be scattered than in the case of black toner. Accordingly, it is possible to prevent the waste toner from being scattered and contaminating the image forming apparatus when the second collection container is replaced.

  Further, according to the present invention, the communication portion between the second guide path and the first recovery container is formed directly above the communication portion between the first guide path and the first recovery container. In the case of color printing, generally, the amount of waste toner remaining on the intermediate transfer belt is larger than the amount of waste toner remaining on one photoconductor, so that a larger amount of waste toner is generated from the upper side in the vertical direction. It will be discharged into the first collection container. As a result, the waste toner is easily scattered in the first collection container, and the waste toner can be prevented from being accumulated at a specific location and solidifying in the first collection container. In addition, the communication portion between the second guide path and the first recovery container is formed directly above the communication portion between the first guide path and the first recovery container, so that the first guide path and the first recovery container are The waste toner solidified in the vicinity of the communicating portion can be dropped downward by the waste toner discharged from the communicating portion between the second guide path and the first collection container.

  According to the present invention, the cross-sectional area perpendicular to the vertical direction of the upper part of the recovery container is smaller than the cross-sectional area perpendicular to the vertical direction of the lower part of the recovery container. Therefore, waste toner that has been discharged into the upper part of the collection container through the first guide path and the second guide path and moved from the upper part of the collection container to the lower part of the collection container is difficult to return to the upper part of the collection container. In addition, it is possible to prevent clogging of the communication part at the upper part of the collection container and the communication part of the second guide path and the upper part of the collection container with waste toner.

1 is a schematic diagram illustrating a configuration of an image forming apparatus 100. FIG. 2 is a schematic diagram illustrating a configuration of a developing device 200. FIG. FIG. 3 is a cross-sectional view of the developing device 200 with a line AA shown in FIG. 3 is a diagram illustrating toner cartridges 300b, 300c, 300m, and 300y and a preliminary collection container 400 in the image forming apparatus 100. FIG. FIG. 5 is a cross-sectional view of the toner cartridge 300y, the photoconductor cleaning unit 25, and the belt cleaning unit 35 with the line BB shown in FIG. FIG. 5 is a cross-sectional view of the toner cartridge 300y and the developing device 200 with the line CC shown in FIG.

  The image forming apparatus 100 including the developing device 200 according to the embodiment of the present invention will be described below. FIG. 1 is a schematic diagram illustrating a configuration of the image forming apparatus 100. In the following description, two directions perpendicular to the paper surface in FIG. 1 are collectively referred to as an X direction, one of which is referred to as an X1 direction, and the other is referred to as an X2 direction. A vertical direction that is perpendicular to the X direction is referred to as a Z direction, an upward direction of the Z direction is referred to as a Z1 direction, and a downward direction is referred to as a Z2 direction. In addition, two directions perpendicular to the X direction and the Z direction are collectively referred to as a Y direction, one of which is referred to as a Y1 direction, and the other is referred to as a Y2 direction.

  The image forming apparatus 100 is a multifunction device having both a copying function, a printer function, and a facsimile function, and forms a full-color or monochrome image on a recording medium according to transmitted image information. The image forming apparatus 100 has three types of printing modes, ie, a copier mode (copy mode), a printer mode, and a facsimile mode, and an operation input from an operation unit (not shown), a personal computer, a portable terminal device, and an information recording medium A print mode is selected by a control unit (not shown) in response to reception of a print job from an external device using the memory device.

  The image forming apparatus 100 includes a toner image forming unit 20, a transfer unit 30, a fixing unit 40, a recording medium supply unit 50, a discharge unit 60, and a control unit unit (not shown). The toner image forming unit 20 includes photosensitive drums 21b, 21c, 21m, and 21y, charging units 22b, 22c, 22m, and 22y, an exposure unit 23, developing devices 200b, 200c, 200m, and 200y, and a photosensitive member cleaning unit. 25b, 25c, 25m, 25y, waste toner collection container integrated toner cartridge (hereinafter simply referred to as “toner cartridge”) 300b, 300c, 300m, 300y, and a preliminary collection container 400. The transfer unit 30 includes an intermediate transfer belt 31, a driving roller 32, a driven roller 33, intermediate transfer rollers 34 b, 34 c, 34 m, 34 y, a belt cleaning unit 35, and a transfer roller 36.

  The photosensitive drum 21, the charging unit 22, the developing device 200, the photosensitive member cleaning unit 25, the toner cartridge 300, and the intermediate transfer roller 34 are black (b), cyan (c), and magenta (m) included in the color image information. In order to correspond to the image information of each color of yellow (y), four each are provided. In this specification, when distinguishing each member provided by four according to each color, an alphabet representing each color is added to the end of a number representing each member as a reference symbol, and when each member is collectively referred to As described above, only numerals representing the respective members are used as reference numerals.

  The photosensitive drum 21 is supported by a drive unit (not shown) so as to be rotatable about an axis, and includes a conductive substrate (not shown) and a photoconductive layer formed on the surface of the conductive substrate. The conductive substrate can take various shapes, and examples thereof include a cylindrical shape, a columnar shape, and a thin film sheet shape. The photoconductive layer is formed of a material that exhibits conductivity when irradiated with light. As the photosensitive drum 21, for example, a cylindrical member (conductive base) formed of aluminum, and amorphous silicon (a-Si), selenium (Se), and the like formed on the outer peripheral surface of the cylindrical member, Alternatively, a film including a thin film (photoconductive layer) made of an organic optical semiconductor (OPC) can be used.

  The charging unit 22, the developing device 200, and the photosensitive member cleaning unit 25 are arranged in this order around the rotation direction of the photosensitive drum 21, and the charging unit 22 is more in the Z direction than the developing device 200 and the photosensitive member cleaning unit 25. It is arranged below.

  The charging unit 22 is a device that charges the surface of the photosensitive drum 21 to a predetermined polarity and potential. The charging unit 22 is installed along the longitudinal direction of the photosensitive drum 21 at a position facing the photosensitive drum 21. In the case of the contact charging method, the charging unit 22 is installed in contact with the surface of the photosensitive drum 21. In the case of the non-contact charging method, the charging unit 22 is installed so as to be separated from the surface of the photosensitive drum 21.

  The charging unit 22 is installed around the photosensitive drum 21 together with the developing device 200, the photosensitive member cleaning unit 25, and the like. The charging unit 22 is preferably installed at a position closer to the photoreceptor drum 21 than the developing device 200, the photoreceptor cleaning unit 25, and the like. As a result, it is possible to reliably prevent the charging failure of the photosensitive drum 21.

  As the charging unit 22, a brush-type charging device, a roller-type charging device, a corona discharge device, an ion generation device, or the like can be used. The brush type charging device and the roller type charging device are contact charging type charging devices. As the brush type charging device, there are a type using a charging brush and a type using a magnetic brush. The corona discharge device and the ion generator are non-contact charging devices. Corona discharge devices include those using wire-like discharge electrodes, those using sawtooth discharge electrodes, and those using needle-like discharge electrodes.

  The exposure unit 23 is arranged such that light emitted from the exposure unit 23 passes between the charging unit 22 and the developing device 200 and is irradiated on the surface of the photosensitive drum 21. The exposure unit 23 irradiates the charged surface of the photosensitive drums 21b, 21c, 21m, and 21y with laser beams corresponding to the image information of the respective colors, so that each of the photosensitive drums 21b, 21c, 21m, and 21y is exposed. An electrostatic latent image corresponding to the image information of each color is formed on the surface. As the exposure unit 23, for example, a laser scanning unit (LSU) including a laser irradiation unit and a plurality of reflection mirrors can be used. As the exposure unit 23, an LED (Light Emitting Diode) array, a unit in which a liquid crystal shutter and a light source are appropriately combined, or the like may be used.

  The developing device 200 is a device that forms a toner image on the photosensitive drum 21 by developing the electrostatic latent image formed on the photosensitive drum 21 with toner. Details of the developing device 200 will be described later.

  The photoconductor cleaning unit 25 removes toner (waste toner) remaining on the surface of the photoconductor drum 21 after the toner image is transferred from the photoconductor drum 21 to the intermediate transfer belt 31, and removes the surface of the photoconductor drum 21. Clean. The photoconductor cleaning unit 25 contacts the photoconductor drum 21 to scrape waste toner, a container 252 for collecting the scraped waste toner, and transports the waste toner in the container 252 to the toner cartridge 300. And a conveying member 253. Details of the photoconductor cleaning unit 25 will be described later.

  The toner cartridge 300 is disposed above the developing device 200 in the Z direction and on the X2 direction side from the developing device 200 and the photosensitive drum 21. The toner cartridge 300 stores unused toner and supplies the toner to the developing device 200. Further, the toner cartridge 300 collects the waste toner that has been transported by the transport member 253 of the photoconductor cleaning unit 25. Details of the toner cartridge 300 will be described later.

  The preliminary collection container 400 is a container connected to the toner cartridge 300y. The preliminary collection container 400 collects waste toner that the toner cartridge 300y can no longer collect. Details of the preliminary collection container 400 will be described later.

  According to such a toner image forming unit 20, the surface of the photosensitive drum 21 that is uniformly charged by the charging unit 22 is irradiated with laser light corresponding to the image information from the exposure unit 23, thereby forming an electrostatic latent image. A toner image is formed by supplying toner from the developing device 200 to the electrostatic latent image. This toner image is transferred to an intermediate transfer belt 31 to be described later. After the toner image is transferred to the intermediate transfer belt 31, waste toner on the surface of the photosensitive drum 21 is removed by the photosensitive member cleaning unit 25.

  The intermediate transfer belt 31 is an endless belt-like member disposed above the photosensitive drum 21 in the Z direction. The intermediate transfer belt 31 is stretched by a driving roller 32 and a driven roller 33 to form a loop-shaped path, and moves as indicated by an arrow A1 in FIG.

  The drive roller 32 is provided so as to be rotatable around its axis by a drive unit (not shown). The drive roller 32 moves the intermediate transfer belt 31 in the direction of the arrow A1 by its rotation. The driven roller 33 is provided so as to be able to rotate following the rotation of the driving roller 32, and generates a certain tension on the intermediate transfer belt 31 so that the intermediate transfer belt 31 does not loosen.

  The intermediate transfer roller 34 is provided in pressure contact with the photosensitive drum 21 via the intermediate transfer belt 31 and rotatable about its axis by a drive unit (not shown). As the intermediate transfer roller 34, for example, a metal (for example, stainless steel) roller having a diameter of 8 mm to 10 mm on which a conductive elastic member is formed can be used. The intermediate transfer roller 34 is connected to a power source (not shown) for applying a transfer bias, and has a function of transferring the toner image on the surface of the photosensitive drum 21 to the intermediate transfer belt 31.

  The transfer roller 36 is provided in pressure contact with the drive roller 32 via the intermediate transfer belt 31 and is rotatable about an axis by a drive unit (not shown). At the pressure contact portion (transfer nip portion) between the transfer roller 36 and the drive roller 32, the toner image carried and conveyed by the intermediate transfer belt 31 is transferred to a recording medium fed from a recording medium supply unit 50 described later. The

  The belt cleaning unit 35 is provided above the intermediate transfer belt 31 in the Z direction. The belt cleaning unit 35 removes toner (waste toner) remaining on the surface of the intermediate transfer belt 31 after the toner image is transferred from the intermediate transfer belt 31 to the recording medium, and cleans the surface of the intermediate transfer belt 31. . If the toner remains on the intermediate transfer belt 31 after the transfer of the toner image to the recording medium, the waste toner adheres to the transfer roller 36 by the movement of the intermediate transfer belt 31, and this attached toner is transferred next. Since the back surface of the recording medium is contaminated, the intermediate transfer belt 31 needs to be cleaned.

  The belt cleaning unit 35 is in contact with the intermediate transfer belt 31 to scrape waste toner, a pumping member 352 for pumping up the scraped waste toner, a container 353 for collecting the pumped waste toner, and a container 353. And a conveying member 354 that conveys the waste toner in the toner cartridge 300y. Details of the belt cleaning unit 35 will be described later.

  According to such a transfer unit 30, when the intermediate transfer belt 31 moves while being in contact with the photosensitive drum 21, the intermediate transfer roller 34 has a transfer bias having a polarity opposite to the charged polarity of the toner on the surface of the photosensitive drum 21. The applied toner image formed on the surface of the photosensitive drum 21 is transferred onto the intermediate transfer belt 31. The toner images of the respective colors respectively formed on the photosensitive drum 21y, the photosensitive drum 21m, the photosensitive drum 21c, and the photosensitive drum 21b are sequentially transferred onto the intermediate transfer belt 31 in this order, thereby transferring full color. A toner image is formed. The toner image transferred to the intermediate transfer belt 31 is conveyed to the transfer nip portion by the movement of the intermediate transfer belt 31, and transferred to the recording medium at the transfer nip portion. The recording medium on which the toner image is transferred is conveyed to a fixing unit 40 described later.

  The recording medium supply unit 50 includes a paper feed box 51, a pickup roller 52, a transport roller 53, and a registration roller 54. The paper feed box 51 is a container-like member that is provided in the lower part of the image forming apparatus 100 in the Z direction and stores a recording medium inside the image forming apparatus 100. Examples of the recording medium include plain paper, color copy paper, overhead projector sheet, and postcard.

  The pickup roller 52 is a member that takes out the recording medium stored in the paper feed box 51 one by one and feeds it to the paper transport path A2. The conveyance rollers 53 are a pair of roller-like members provided so as to be in pressure contact with each other, and convey the recording medium toward the registration rollers 54 in the sheet conveyance path A2. The registration rollers 54 are a pair of roller-like members provided so as to be in pressure contact with each other, and the toner image carried on the intermediate transfer belt 31 is conveyed to the transfer nip portion on the recording medium fed from the conveyance roller 53. In synchronism with this, the sheet is fed to the transfer nip portion.

  According to such a recording medium supply unit 50, the recording medium is fed from the paper supply box 51 to the transfer nip portion in synchronization with the toner image carried on the intermediate transfer belt 31 being conveyed to the transfer nip portion. Then, the toner image is transferred to the recording medium.

  The fixing unit 40 includes a heating roller 41 and a pressure roller 42. The heating roller 41 is controlled to have a predetermined fixing temperature. The pressure roller 42 is a roller that is in pressure contact with the heating roller 41. The heating roller 41 nips the recording medium together with the pressure roller 42 while heating, thereby melting and fixing the toner constituting the toner image on the recording medium. The recording medium on which the toner image is fixed is conveyed to the discharge unit 60.

  The discharge unit 60 includes a conveyance roller 61, a discharge roller 62, and a discharge tray 63. The conveyance roller 61 is a pair of roller-like members provided so as to be in pressure contact with each other above the fixing unit 40 in the Z direction. The conveyance roller 61 conveys the recording medium on which the image is fixed toward the discharge roller 62.

  The discharge roller 62 is a pair of roller-like members provided so as to be in pressure contact with each other. The discharge roller 62 discharges the recording medium on which printing has been completed to the discharge tray 63. The discharge tray 63 is provided on the upper surface in the Z direction of the image forming apparatus 100 and stores a recording medium on which an image is fixed.

  Image forming apparatus 100 includes a control unit (not shown). The control unit unit is provided, for example, at an upper portion in the Z direction in the internal space of the image forming apparatus 100 and includes a storage unit, a calculation unit, and a control unit. The storage unit stores various setting values via an operation panel (not shown) arranged on the upper surface in the Z direction of the image forming apparatus 100, detection results from sensors (not shown) arranged at various locations inside the image forming apparatus 100, external devices, and the like. The image information from is input. A program for executing various processes is written in the storage unit. Examples of the various processes include a recording medium determination process, an adhesion amount control process, and a fixing condition control process.

  As the storage unit, those commonly used in this field can be used, and examples thereof include a read only memory (ROM), a random access memory (RAM), and a hard disk drive (HDD). As the external device, an electric or electronic device that can form or acquire image information and can be electrically connected to the image forming apparatus 100 can be used. For example, a computer, a digital camera, a television receiver, a video recorder DVD (Digital Versatile Disc) recorder, HDDVD (High-Definition Digital Versatile Disc) recorder, Blu-ray disc recorder, facsimile apparatus, portable terminal apparatus, and the like.

  The calculation unit retrieves various data (image formation command, detection result, image information, etc.) written in the storage unit and various processing programs, and performs various determinations. The control unit performs operation control by sending a control signal to each device provided in the image forming apparatus 100 according to the determination result of the calculation unit.

  The control unit and the calculation unit include a processing circuit realized by a microcomputer, a microprocessor, or the like provided with a central processing unit (CPU). The control unit unit includes a main power source together with the processing circuit, and the power source supplies power not only to the control unit unit but also to each device provided in the image forming apparatus 100.

  Next, a detailed configuration of the developing device 200 will be described. FIG. 2 is a schematic diagram illustrating a configuration of the developing device 200. FIG. 3 is a cross-sectional view of the developing device 200 with the line AA shown in FIG.

  The developing device 200 is a device that develops an electrostatic latent image formed on the surface of the photosensitive drum 21 by supplying toner to the surface of the photosensitive drum 21. The developing device 200 includes a developing tank 201, a first conveying member 202, a second conveying member 203, a developing roller 204, a developing tank cover 205, a doctor blade 206, a partition wall 207, and a toner concentration detection sensor 208. including.

  The developing tank 201 is a member in which an internal space is formed by the side wall portions 201a and 201b and the bottom wall portion 201c, and a two-component developer composed of toner and a carrier is stored in the internal space. The side wall parts 201a and 201b and the bottom wall part 201c may be integrally formed, or may be separate members. The developing tank 201 is made of a resin material such as polyethylene, polypropylene, high impact polystyrene, and ABS resin (acrylonitrile-butadiene-styrene copolymer synthetic resin). The developer used in the present invention may be a one-component developer composed only of toner or a two-component developer containing toner and carrier.

  In the developing tank 201, a developing tank cover 205 is provided above the Z direction, and a first conveying member 202, a second conveying member 203, a developing roller 204, a doctor blade 206, and a partition wall 207 are provided in the internal space. In addition, a toner concentration detection sensor 208 is provided in the lower part (bottom part) of the developing tank 201 in the Z direction.

  The developing tank 201 is provided with an opening between the photosensitive drum 21 and the developing roller 204. The developing roller 204 includes a magnet roller, carries the two-component developer in the developing tank 201 on the surface, and supplies toner contained in the carried two-component developer to the photosensitive drum 21. A power supply (not shown) is connected to the developing roller 204, and a developing bias voltage is applied. The toner carried on the developing roller 204 moves to the photosensitive drum 21 in the vicinity of the photosensitive drum 21 by electrostatic force due to the developing bias voltage.

  The doctor blade 206 is a rectangular plate-like member extending in the axial direction of the developing roller 204, one end in the width direction is fixed to the developing tank 201, and the other end is provided at a distance from the surface of the developing roller 204. It is done. An interval (doctor gap) between the doctor blade 206 and the developing roller 204 is, for example, 0.4 mm to 2.0 mm. The doctor blade 206 is provided at a distance from the surface of the developing roller 204, thereby restricting the amount of developer carried on the developing roller 204 to a predetermined amount. Examples of the material of the doctor blade 206 include stainless steel, aluminum, and synthetic resin.

  The partition wall 207 is a member that extends along the longitudinal direction of the developing tank 201 at a substantially central portion in the width direction of the developing tank 201. The partition wall 207 is provided between the bottom wall portion 201 c of the developing tank 201 and the developing tank cover 205, and is provided so that both end portions in the longitudinal direction are separated from the side wall portions 201 a and 201 b of the developing tank 201. The partition 207 divides the internal space of the developing tank 201 into a first conveyance path P, a second conveyance path Q, a first communication path R, and a second communication path S.

  The second transport path Q is a substantially semi-cylindrical space extending along the longitudinal direction of the partition wall 207 and is a space facing the developing roller 204. The first transport path P is a substantially semi-cylindrical space extending along the longitudinal direction of the partition wall 207 and is a space facing the second transport path Q across the partition wall 207. The first communication path R is a space that communicates the first transport path P and the second transport path Q on the longitudinal end 207a side of the partition wall 207. The second communication path S is a space that communicates the first transport path P and the second transport path Q on the side of the other end 207 b in the longitudinal direction of the partition wall 207.

  The developing tank cover 205 is detachably provided above the developing tank 201 in the Z direction, and has a supply port 205a. The toner cartridge 300 is connected to the developing tank cover 205 at the supply port 205a. The supply port 205a is an opening in which an opening for supplying toner to the developing tank 201 is formed, and the toner accommodated in the toner cartridge 300 is supplied into the developing tank 201 through this opening. .

  The supply port 205a is provided in the vicinity of the second communication path S above the first transport path P in the Z direction. More specifically, the opening formed in the supply port portion 205 a is provided so as to face the first transport path P and be at the same position as the second communication path S in the longitudinal direction of the partition wall 207.

  The first transport member 202 is provided in the first transport path P. The first conveying member 202 conveys the developer in the developing tank 201 from the other end 207b in the longitudinal direction of the partition wall 207 toward the one end 207a in the longitudinal direction, that is, in the X1 direction.

  The 1st conveyance member 202 is an auger screw-like member containing the rotating shaft member 202a, the spiral blade 202b, and the gear 202c. The rotating shaft member 202a is a cylindrical member having a diameter of 4 mm to 10 mm, and is connected to the gear 202c at the end in the X1 direction. The rotating shaft member 202a is supported rotatably around the axis by a bearing (not shown) fixed to the side wall 201a of the developing tank 201 and a bearing (not shown) fixed to the side wall 201b of the developing tank 201. A spiral blade 202b, which is a member that spirally surrounds the side surface, is provided on the side surface of the rotating shaft member 202a.

  The rotating shaft member 202a, the spiral blade 202b, and the gear 202c are formed of a resin material such as polyethylene, polypropylene, high impact polystyrene, and ABS resin, for example. The rotary shaft member 202a, the spiral blade 202b, and the gear 202c are preferably integrally formed from the same material.

  Such a first conveying member 202 is rotated at 150 rpm to 400 rpm around the axis of the rotating shaft member 202a through a gear 202c by a rotation driving source such as a motor (not shown) provided in the image forming apparatus 100. At this time, the spiral blade 202b rotates around the axis of the rotating shaft member 202a. Specifically, the portion of the spiral blade 202b located at the top in the Z direction moves away from the partition wall 207 and rotates in the rotational direction approaching the bottom wall 201c of the developing tank 201. As a result of such rotational movement, the developer stored in the first transport path P is transported in the X1 direction. As described above, the supply port 205a of the developing tank cover 205 is formed in the vicinity of the second communication path S above the first conveyance path P in the Z direction. First, it is supplied to the first transport path P, and then transported along the first transport path P in the X1 direction by the first transport member 202.

  The second transport member 203 is provided in the second transport path Q. The second conveying member 203 conveys the developer in the developing tank 201 from the longitudinal one end 207a side of the partition wall 207 toward the longitudinal other end 207b, that is, in the X2 direction.

  The second transport member 203 is an auger screw-like member including a rotating shaft member 203a, a spiral blade 203b, and a gear 203c. The rotating shaft member 203a is a columnar member having a diameter of 4 mm to 10 mm, and is connected to the gear 203c at the end in the X1 direction. The rotary shaft member 203a is supported rotatably around the axis by a bearing (not shown) fixed to the side wall 201a of the developing tank 201 and a bearing (not shown) fixed to the side wall 201b of the developing tank 201. A spiral blade 203b that is a member that spirally surrounds the side surface is provided on the side surface of the rotating shaft member 203a.

  The rotating shaft member 203a, the spiral blade 203b, and the gear 203c are formed of a resin material such as polyethylene, polypropylene, high impact polystyrene, and ABS resin, for example. The rotating shaft member 203a, the spiral blade 203b, and the gear 203c are preferably integrally formed from the same material.

  The second transport member 203 is rotated at 150 rpm to 400 rpm around the axis of the rotary shaft member 203a via the gear 203c by a rotational drive source such as a motor (not shown) provided in the image forming apparatus 100. At this time, the spiral blade 203b rotates around the axis of the rotating shaft member 203a. Specifically, the portion of the spiral blade 203b located at the top in the Z direction moves away from the partition wall 207 and rotates in the rotational direction approaching the bottom wall 201c of the developing tank 201. As a result of such rotational movement, the developer stored in the second transport path Q is transported in the X2 direction.

  The toner density detection sensor 208 is mounted at the bottom of the developing tank 201 below the second transport member 203 in the Z direction so that the sensor surface is exposed to the second transport path Q. The toner concentration detection sensor 208 is electrically connected to a toner concentration control unit (not shown).

  The toner density control unit controls the toner cartridge 300 according to the toner density detection result detected by the toner density detection sensor 208 to supply the toner into the developing tank 201. More specifically, the toner concentration control unit determines whether or not the toner concentration detection result by the toner concentration detection sensor 208 is lower than a predetermined set value, and controls the toner cartridge 300 when determining that the toner concentration detection result is lower. Then, toner is supplied into the developing tank 201.

  A power source (not shown) is connected to the toner concentration detection sensor 208. The power supply applies to the toner concentration detection sensor 208 a drive voltage for driving the toner concentration detection sensor 208 and a control voltage for outputting the toner concentration detection result to the toner concentration control unit. Application of a voltage to the toner concentration detection sensor 208 by the power supply is controlled by a control unit (not shown).

  As the toner concentration detection sensor 208, a general toner concentration detection sensor can be used. For example, a transmitted light detection sensor, a reflected light detection sensor, a magnetic permeability detection sensor, or the like can be used. Among these toner concentration detection sensors, it is preferable to use a magnetic permeability detection sensor. Examples of the magnetic permeability detection sensor include TS-L (trade name, manufactured by TDK Corporation), TS-A (trade name, manufactured by TDK Corporation), TS-K (trade name, manufactured by TDK Corporation), and the like. It is done.

  According to the developing device 200 configured as described above, the two-component developer is referred to as the first conveyance path P, the first communication path R, the second conveyance path Q, and the second communication path S in the developing tank 201. Circulated in order. A part of the two-component developer circulated and conveyed is carried on the surface of the developing roller 204 in the second conveyance path Q, and the toner in the carried two-component developer moves to the photosensitive drum 21. Are consumed sequentially. When the toner concentration detection sensor 208 detects that a predetermined amount of toner has been consumed, unused toner is supplied from the toner cartridge 300 into the first conveyance path P. The supplied toner is diffused in the already stored two-component developer while being conveyed in the first conveyance path P. As a result, the toner concentration of the two-component developer stored in the developing tank 201 increases, and continuous development becomes possible.

  Next, detailed configurations of the toner cartridge 300, the preliminary collection container 400, the photosensitive member cleaning unit 25, and the belt cleaning unit 35 will be described. FIG. 4 is a diagram illustrating the toner cartridges 300b, 300c, 300m, and 300y and the preliminary collection container 400 in the image forming apparatus 100. FIG. 5 is a cross-sectional view of the toner cartridge 300y, the photoconductor cleaning unit 25, and the belt cleaning unit 35 with the line BB shown in FIG. FIG. 6 is a cross-sectional view of the toner cartridge 300y and the developing device 200 in which the line CC shown in FIG.

  The toner cartridge 300 includes a toner supply unit 301 that supplies toner to the developing device 200 and a waste toner collection container 302 that collects waste toner on the photosensitive drum 21. The toner cartridge 300 communicates with the container 252 of the photoconductor cleaning unit 25, and a first receiving port 303 that receives waste toner conveyed from the photoconductor drum 21 is formed. The toner cartridges 300b, 300c, and 300m are configured in the same shape, but the toner cartridge 300y communicates with the container 353 of the belt cleaning unit 35, and receives a waste toner conveyed from the intermediate transfer belt 31. The shape is different in that a waste toner discharge port 305y that communicates with 304y and the preliminary recovery container 400 and discharges the waste toner is formed in the preliminary recovery container 400. Since the shape is not different except for this point, only the toner cartridge 300y will be described below, and description of the toner cartridges 300b, 300c, and 300m will be omitted.

  The toner supply unit 301y includes a toner storage unit 306y, a toner discharge unit 307y, and a toner discharge member 308y. The toner replenishing unit 301y is configured to replenish unused toner stored in the toner storage unit 306y to the developing device 200y via the toner discharging unit 307y by the toner discharging member 308y.

  The toner storage unit 306y is a container having a rectangular parallelepiped appearance, and stores unused toner. The toner storage unit 306y is connected to the toner discharge unit 307y and communicates with the toner discharge unit 307y at the lower end in the Z direction, the end in the Y2 direction, and the end in the X1 direction. An inclined portion 309y that descends in the Z direction as it approaches the toner discharge portion 307y in the Y direction is provided in the toner storage unit 306y. By the inclined portion 309y, the toner in the toner storage portion 306y moves toward the toner discharge portion 307y.

  A sensor 310y that detects whether or not toner remains in the toner storage unit 306y is provided in the vicinity of the toner discharge unit 307y in the inclined unit 309y. The sensor 310y is the “first detection unit” in the present invention, and a piezoelectric sensor, a transmissive photosensor, or the like can be used. The “first detection unit” in the present invention may be the toner concentration detection sensor 208 of the developing device 200. For example, if the detection result of the toner concentration detection sensor 208 does not change even if the toner cartridge 300 is controlled so that the toner concentration control unit supplies toner based on the detection result of the toner concentration detection sensor 208, the toner storage unit 306y. It is possible to indirectly detect that no toner remains inside.

  When the sensor 310y detects that no toner remains in the toner storage unit 306y, the image forming apparatus 100 notifies an operation panel (not shown) that it is time to replace the toner cartridge 300. This operation panel corresponds to the “first notification unit” in the present invention, and displays, for example, a sentence such as “no toner” to notify that it is time for replacement.

  The toner discharge portion 307y is a cylindrical member having a toner discharge port 311y formed at the lower end in the Z direction and at the end in the X1 direction. The toner discharge portion 307y is disposed so that the toner discharge port 311y and the opening of the supply port portion 205a of the developing device 200 communicate with each other.

  The toner storage unit 306y and the toner discharge unit 307y are made of, for example, a resin material such as polyethylene, polypropylene, high impact polystyrene, or ABS resin. The toner storage unit 306y and the toner discharge unit 307y are preferably integrally formed from the same material.

  The toner discharge member 308y is an auger screw-like member having the X direction as a longitudinal direction, one end in the longitudinal direction is supported by the inner wall portion of the toner storage unit 306y, and the other end in the longitudinal direction is supported by the toner discharge unit 307y. . The toner discharge member 308y rotates around the axis, thereby conveying the toner in the toner storage unit 306y and the toner discharge unit 307y toward the toner discharge port 311y and discharging the toner from the toner discharge port 311y. The discharged toner is supplied to the developing device 200.

  The waste toner collecting container 302y is a container for collecting the waste toner conveyed from the photosensitive drum 21y and the intermediate transfer belt 31, and is a “first collecting container” in the present invention. The waste toner collecting container 302y is formed with a first receiving port 303y communicating with the container 252y of the photoreceptor cleaning unit 25y and a second receiving port 304y communicating with the container 353 of the belt cleaning unit 35. The waste toner collection container 302y has an L-shaped hollow body having a rectangular parallelepiped collection container upper part 312y whose appearance is the Z direction as a longitudinal direction and a rectangular collection container lower part 313y whose appearance is the Y direction as a longitudinal direction. Configure. Further, the L-shaped hollow body and the toner storage unit 306y constitute a hollow body having a rectangular parallelepiped appearance.

  The lower portion in the Z direction of the recovery container upper portion 312y and the upper portion in the Z direction of the recovery container lower portion 313y communicate with each other. The cross-sectional area perpendicular to the Z direction of the recovery container upper part 312y is smaller than the cross-sectional area perpendicular to the Z direction of the recovery container lower part 313y, and in this embodiment, 1 / of the cross-sectional area perpendicular to the Z direction of the recovery container lower part 313y. 10 to 1/2.

  A first receiving port 303y and a second receiving port 304y are formed in the recovery container upper part 312y. The second receiving port 304y is preferably formed above the first receiving port 303y in the Z direction. In the present embodiment, the second receiving port 304y is formed directly above the first receiving port 303y in the Z direction.

As described above, the first receiving port 303y communicates with the container 252y of the photoreceptor cleaning unit 25y. The container 252y is the “first guide path” in the present invention. Further, the conveying member 253y provided in the container 252y is the “first waste toner conveying member” in the present invention, and surrounds the cylindrical first rotating shaft member 254y and the first rotating shaft member 254y. by first rotating shaft member 254y is rotated along with the rotation in the rotation direction G ₁ about the axis, and a first spiral blade 255y to convey the waste toner toward the photosensitive drum 21y to the first receiving port 303y including. Rotation direction G _1, when viewed in the direction X1, part located in the Z direction lowermost first spiral blade 255y is a rotational direction from the waste toner container 302y to preliminary collection container 400, the present embodiment Then, the rotation direction is counterclockwise.

As described above, the second receiving port 304y communicates with the container 353 of the belt cleaning unit 35. The container 353 is a “second guide path” in the present invention. Further, the conveying member 354 provided in the container 353 is a “second waste toner conveying member” in the present invention, and surrounds the cylindrical second rotating shaft member 355 and the second rotating shaft member 355. by the second rotation axis member 355 is rotated along with the rotation in the rotation direction G ₂ about the axis, and the second helical blade 356 for conveying the waste toner toward the intermediate transfer belt 31 to the second receiving port 304y including. Rotation direction G ₂ is, when viewed in the direction X1, part located in the Z direction lowermost second spiral blade 356, a rotational direction from the waste toner container 302y to preliminary collection container 400, the present embodiment Then, the rotation direction is counterclockwise.

  The upper portion in the Z direction of the recovery container lower portion 313y is in contact with the lower portion in the Z direction of the toner storage unit 306y, and is positioned below the toner discharge member 308y in the Z direction. Further, the X1 direction end of the collection container lower portion 313y is in contact with the side wall 201b of the developing tank 201 of the developing device 200.

  The collection container upper part 312y and the collection container lower part 313y are formed of a resin material such as polyethylene, polypropylene, high impact polystyrene, ABS resin, for example. In the present embodiment, the recovery container lower part 313y is formed of a material having higher thermal conductivity than the material of the toner storage unit 306 and the developing tank 201.

  A waste toner discharge port 305y is formed in the lower portion 313y of the collection container in the upper portion of the side wall in the Z direction. When the waste toner collects in the waste toner collection container 302y to a predetermined height in the Z direction, waste toner that does not fully enter the waste toner collection container 302y overflows. The overflowing waste toner is collected in the preliminary collection container 400.

  The preliminary collection container 400 is a container in which a waste toner receiving port 401 communicating with the waste toner discharge port 305y is formed. The preliminary collection container 400 is a “second collection container” in the present invention, and collects the waste toner discharged from the waste toner discharge port 305 y via the waste toner receiving port 401. The preliminary collection container 400 is detachably attached to the image forming apparatus 100 and can be replaced by a user.

  The preliminary collection container 400 is provided with a sensor 402 that detects whether or not the preliminary collection container 400 is full of waste toner at a position below the waste toner receiving port 401 in the Z direction. The sensor 402 is a “second detection unit” in the present invention, and a piezoelectric sensor, a transmissive photosensor, or the like can be used.

  When the sensor 402 detects that the preliminary collection container 400 is full of waste toner, the image forming apparatus 100 notifies an operation panel (not shown) that it is time to replace the preliminary collection container 400. . This operation panel corresponds to the “second notification unit” in the present invention, and displays, for example, a sentence such as “full of waste toner” to notify that it is time for replacement.

  According to the image forming apparatus 100 of the present invention configured as described above, the toner replenishing unit 301y that replenishes yellow toner and the waste toner collection container 302y that collects waste toner are integrated. When it is notified that it is time to replace based on the detection result of the sensor 310y, these can be replaced at the same time, and the user's effort can be reduced. Further, when the waste toner collection container 302y is full of waste toner, waste toner that does not fit in the waste toner collection container 302y can be collected in the preliminary collection container 400, and replaced based on the detection result of the sensor 402. When it is notified that it is time, the preliminary collection container 400 can be replaced. Further, since the waste toner collecting container 302y does not require a sensor for detecting that the waste toner is full, the number of parts can be reduced.

  In addition, since the preliminary collection container 400 is not connected to the toner cartridge 300 of a color other than yellow, the waste toner collection container 302 is prevented so that the waste toner collection container 302 is not filled before the toner in the toner supply unit 301 is used up. It is preferable to sufficiently increase the volume. For example, if the volume of the waste toner collection container 302 is approximately the same as the volume of the toner storage unit 306, the toner in the toner replenishment unit 301 can be used up reliably before the waste toner collection container 302 becomes full. .

  For the yellow toner cartridge 300y, the volume of the waste toner collection container 302y is preferably set to 1 to 2 times the volume of the toner storage unit 306y in order to make the replacement timing of the preliminary collection container 400 as late as possible. Within this range, the volume of the waste toner collection container 302y does not become too large, and there is a high possibility that the toner in the toner replenishing section 301y will be used up before the waste toner collection container 302y becomes full. The replacement time of the collection container 400 can be delayed. If the replacement timing of the preliminary collection container 400 is delayed, the serviceman can replace the preliminary collection container 400 together with the replacement of other members during maintenance of other members such as the intermediate transfer belt 31, so that the user Can be reduced.

  In the present embodiment, the preliminary collection container 400 is connected to the yellow toner cartridge 300. Thus, it is preferable that the preliminary collection container 400 is connected to the toner cartridge 300 for supplying color toner. In the case of a color toner, it is generally used less frequently than a black toner, and it takes time until the toner in the toner cartridge 300 is used up. As a result, compared with black toner, color toner deteriorates with time until it is used up, and fluidity decreases. Therefore, the waste toner collected in the preliminary collection container 400 also has low fluidity and is difficult to be scattered. As a result, it is possible to prevent waste toner from being scattered and contaminating the inside of the image forming apparatus 100 when the preliminary collection container 400 is replaced.

  In the present embodiment, the waste toner collection container 302y connected to the preliminary collection container 400 is in contact with the lower part in the Z direction of the toner storage unit 306y. Heat is generated by the rotation of the toner discharge member 308y at the lower portion of the toner storage unit 306y in the Z direction. In this embodiment, the waste toner in the waste toner collection container 302y is warmed by this heat, thereby reducing the fluidity and making it difficult to scatter the toner in the preliminary collection container 400. Similarly, the waste toner collecting container 302y is in contact with the side wall 201b of the developing tank 201, and the waste toner in the waste toner collecting container 302y is warmed by heat generated in the developing tank 201, thereby being fluid. Can be recovered in the preliminary recovery container 400 in a state in which it is difficult to scatter. In this embodiment, the waste toner collecting container 302y takes heat from the toner storage unit 306y and the developing tank 201 in this way, so that the toner storage unit 306y and the developing tank 201 can be cooled, and the toner It is possible to prevent deterioration of unused toner in the storage unit 306y and toner immediately before use in the developing tank 201. The effects as described above can be further enhanced by using a material having higher thermal conductivity than the toner storage unit 306y and the developing tank 201 as the material of the waste toner collecting container 302y.

  In the present embodiment, the second receiving port 304y is formed immediately above the first receiving port 303y in the Z direction. Accordingly, the container 353 of the belt cleaning unit 35 is provided above the container 252 of the photosensitive member cleaning unit 25 in the Z direction. In the case of color printing, generally, the amount of waste toner remaining on the intermediate transfer belt 31 is larger than the amount of waste toner remaining on the photosensitive drum 21y. A large amount of waste toner is discharged into the waste toner collecting container 302y. As a result, the waste toner is easily scattered in the waste toner collection container 302y, and it is possible to prevent the waste toner from being accumulated at a specific location and solidifying in the waste toner collection container 302y. Further, since the second receiving port 304y is formed immediately above the first receiving port 303y in the Z direction, the waste toner solidified in the vicinity of the first receiving port 303y is caused by the waste toner discharged from the second receiving port 304y. Can drop down. Note that the conveyance speed of the conveyance member 354 of the belt cleaning unit 35 is the conveyance speed of the conveyance member 253y of the photosensitive member cleaning unit 25y so that the waste toner does not solidify in the vicinity of the second receiving port 304y that discharges a larger amount of waste toner. Is faster. For example, the conveyance speed of the conveyance member 354 is set to 2 to 4 times the conveyance speed of the conveyance member 253y.

  In the present embodiment, the cross-sectional area perpendicular to the Z direction of the recovery container upper part 312y is smaller than the cross-sectional area perpendicular to the Z direction of the recovery container lower part 313y. Accordingly, the waste toner discharged from the first receiving port 303y and the second receiving port 304y into the waste toner collecting container 302y and moved from the collecting container upper part 312y to the collecting container lower part 313y is difficult to return to the collecting container upper part 312y. Thus, the first receiving port 303y and the second receiving port 304y can be prevented from being clogged with waste toner.

In the present embodiment, the conveying member 253y of the photoconductor cleaning unit 25y is rotated in the rotation direction _{G 1} to the portion positioned in the Z direction lowermost first spiral blade 255y is directed to pre-collection container 400 from the waste toner collecting container 302y . Therefore, the waste toner that is transported by the transport member 253y and discharged from the first receiving port 303y into the waste toner collecting container 302y is easily moved to the preliminary collecting container 400 side, and is located below the first receiving port 303y in the Z direction. Only the waste toner can be prevented from accumulating and solidifying. Similarly, in the present embodiment, the conveyance member 354 of the belt cleaning unit 35, the rotation direction G ₂ that portions located in the Z direction lowermost second spiral blade 356 toward the pre-collection container 400 from the waste toner collecting container 302y Rotate. Accordingly, the waste toner that is transported by the transport member 354 and discharged from the second receiving port 304y into the waste toner collecting container 302y is easily moved to the preliminary collecting container 400 side, and is located below the second receiving port 304y in the Z direction. Only the waste toner can be prevented from accumulating and solidifying.

20 Toner image forming portions 21, 21b, 21c, 21m, 21y Photosensitive drums 25, 25b, 25c, 25m, 25y Photosensitive member cleaning unit 30 Transfer portion 31 Intermediate transfer belt 35 Belt cleaning unit 40 Fixing portion 50 Recording medium supply portion 60 Ejector 100 Image forming apparatus 200, 200b, 200c, 200m, 200y Developing device 252y Container 253y Conveying member 254y First rotating shaft member 255y First spiral blade 300, 300b, 300c, 300m, 300y Toner cartridge 301y Toner replenisher 302y Waste Toner recovery container 310y sensor 311y upper part of recovery container 312y lower part of recovery container 353 container 354 conveying member 355 second rotating shaft member 356 second spiral blade 400 preliminary recovery container 402 sensor

Claims (4)

In an image forming apparatus for transferring a toner image formed on a photoreceptor by a developing device to a recording medium via an intermediate transfer belt and forming an image on the recording medium.
A toner supply device for supplying toner to the developing device;
A first collection container provided integrally with the toner replenishing device and collecting waste toner;
A first guide path that communicates with the first recovery container and guides the waste toner on the photoreceptor to the first recovery container;
A second guide path communicating with the first recovery container and guiding waste toner on the intermediate transfer belt to the first recovery container;
A second collection container that communicates with the first collection container and collects waste toner overflowing from the first collection container;
A first detector for detecting whether toner remains in the toner replenishing device;
A first notification unit for notifying that it is time to replace the toner supply device and the first collection container when no toner remains in the toner supply device;
A second detector for detecting whether or not the inside of the second collection container is full of waste toner;
An image forming apparatus comprising: a second notification unit that notifies that it is time to replace the second collection container when the second collection container is full of waste toner.   The image forming apparatus according to claim 1, wherein the toner replenishing device is a color toner replenishing device that replenishes color toner.   The second guide path is provided such that a communication portion between the second guide path and the first recovery container is positioned directly above a communication portion between the first guide path and the first recovery container. The image forming apparatus according to claim 1, wherein the image forming apparatus is an image forming apparatus. The first collection container is
An upper part of the recovery container that communicates with the first guide path and the second guide path, and a lower part of the recovery container that is positioned vertically below the upper part of the recovery container and communicates with the second recovery container. Including
The cross-sectional area perpendicular to the vertical direction of the upper part of the collection container is provided so as to be smaller than the cross-sectional area perpendicular to the vertical direction of the lower part of the collection container. The image forming apparatus described.

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