JP5531644B2 - Image forming apparatus - Google Patents

Description

  The present invention relates to an image forming apparatus such as a copying machine, a printer, and a facsimile.

  2. Description of the Related Art Conventionally, in a developing device of an image forming apparatus, when toner in a developing device is insufficient due to development, toner stored in a toner bottle installed outside the developing device is transferred from a toner supply port of the developing device to the developing device. At the time of shipment, installation, maintenance, etc., a serviceman fills an empty developer container with a two-component developer consisting of toner and carrier from the developer filling port of the developing device. . Here, the developer storage portion of the developing device for storing the developer is not filled with the developer in advance, and the image forming apparatus is not shipped because the developing roller is subjected to vibration during transportation or the entire apparatus is inclined. This is because the developer may be scattered from the opening of the developing device for partial exposure. Further, when the two-component developer is repeatedly used, the carrier component gradually deteriorates and the developing ability is lowered. Therefore, the developer including the deteriorated carrier is replaced by a serviceman.

  Although the developer filling method varies depending on the developing device, the toner replenishing port for replenishing the toner from the toner bottle is used not only for the toner replenishment but also for the filling of the developer. Remove the unit once, set the developer bottle in the toner replenishing port of the developing device and then fill the developer, and in addition to the toner replenishing port, there is a developer filling port dedicated for developer filling And a developing device of a type that fills the developer from the developer filling port.

  However, when it is necessary to remove the toner replenishment unit, the work involved is relatively complicated, and the interruption time until printing is possible becomes longer. Further, in the case of a developing device having a dedicated developer filling port, the developer filling port is disposed on the side opposite to the toner replenishing port, and development is performed by providing these replenishing ports and filling ports individually. The size of the apparatus and the image forming apparatus is large, and since there are many openings, foreign matter is mixed in and toner / developer scattering is increased.

  Even if these replenishing ports / filling ports are arranged on one side of the developing device, if each of them is formed independently and has an independent opening, the size of the device is increased. In the toner filling / conveying portion, since an inclined surface serving as a reservoir for toner or developer is formed, smooth toner replenishment and developer filling may be hindered or overflowed.

  In the image forming apparatus described in Patent Document 1, since a toner replenishing port for replenishing toner from a toner bottle is also used as a developer filling port, a service person is attached at the time of collecting the apparatus. By removing the toner replenishing device and separating the intermediate transfer belt from the photoreceptor, the developer from the developer bottle containing the developer is filled into the developing device through the toner replenishing port.

  In view of the above, the present invention realizes charging of the developer into the developing device and replenishment of toner without the need to remove the toner replenishing unit or the like from the developing device, and prevents toner, developer accumulation, overflow and scattering. For the purpose.

The problem is that the image forming apparatus according to the present invention includes an image carrier, a developing device for developing a latent image on the image carrier using a developer, and a toner containing toner to be supplied to the developing device. And a toner replenishing port for replenishing toner from the toner bottle, a communication port communicating with the developing device, and a developer filling port for filling the developer, and the toner replenishing port comprising a toner supply passage extending in the vertical direction to the continuous opening, and the developer supply passage leading to intersect obliquely from above with respect to the toner supply passage, the developer guide member having from developer guide member is solved by a developer filling port is provided for the developing device so as to face the front side of the image forming apparatus.

Further, it is preferable that the developer guide member has a linear hollow substrate, the toner replenishing port is formed in the upper portion of the hollow substrate, and the developer filling port protrudes from the side surface of the hollow substrate.
Further, it is preferable that the developer guide member is disposed perpendicular to the developer transport member provided in the developing device.

Further, it is preferable that the communication port of the developer guide member communicating with the developing device communicates with a position outside the developer circulation path in the developing device.
Furthermore, it is preferable that an opening for allowing air to escape to the outside when the developer is filled is provided at a position facing the developer filling port of the developer guide member.

Preferably, the developer guide member is covered with a protective cover, and the developer filling port is covered with a developer filling port cover that can be attached to and detached from the protective cover.
Furthermore, when filling the developer, it is preferable that the developer filling auxiliary member is fitted into the developer filling port, and the passage to the toner replenishing port in the developer guide member is blocked by the developer filling auxiliary member.

The developer filling auxiliary member is preferably a funnel.
Further, it is preferable that the toner replenishing port is formed to be inclined with respect to a horizontal plane, and an elastic member is attached to the upper portion of the toner replenishing port.

  According to the present invention, since a toner replenishing port and a developer filling port are provided in one developer guide member, both the toner replenishment and the developer filling to the developing device can be performed using this developer guide member. Thus, the developing device can be downsized, the developer can be prevented from overflowing and collecting when the toner is replenished or the developer is charged, and the developer can be filled even when the developing device is in use.

1 is an overall configuration diagram illustrating a printer as an image forming apparatus. It is a perspective view of the developing device provided with the developer guide member according to the present invention. FIG. 3 is a perspective view of a developer guide member according to the present invention, a sub hopper joined to the developer guide member, and a developing device. It is a longitudinal cross-sectional view of a developer guide member and a developing device. FIG. 4 is a perspective view of the developing device covered with a protective cover, showing a state where a developer filling port cover is mounted. FIG. 7 is a perspective view of the developing device covered with a protective cover, showing a state where a developer filling port cover is removed. It is a figure which shows the state with which the funnel was mounted | worn with the developer filling port of the developer guide member. It is a longitudinal cross-sectional view of a developer guide member and a developing device to which a funnel is attached. FIG. 4 is a plan sectional view of the developing device showing a developer circulation path and a fitting position between the developer guide member and the developing device. It is a longitudinal cross-sectional view of the developer guide member and developing device of another embodiment with which the funnel was mounted | worn.

First, a series of image forming processes in the image forming apparatus will be described.
FIG. 1 is an overall configuration diagram illustrating a printer as an image forming apparatus. As shown in FIG. 1, four toner cartridges 32Y, 32C, 32M, and 32K corresponding to the respective colors (yellow, cyan, magenta, and black) are detachably attached to the cartridge housing portion 31 above the image forming apparatus main body 100. It is installed (changeable). The toner cartridge may be a developer cartridge that contains toner and a carrier, and stores a premix toner that is a developer having a larger proportion of toner than the developer in the developing device.
An intermediate transfer unit 15 is disposed below the cartridge housing portion 31. Image forming portions (photosensitive drums 21Y, 21C, 21M, and 21K as image bearing members) and development corresponding to each color (yellow, cyan, magenta, black) so as to face the intermediate transfer belt 18 of the intermediate transfer unit 15 Devices 23Y, 23C, 23M, 23K and the like are installed).

  The image forming unit for each color includes a photosensitive drum 21, a charging unit (not shown) disposed around the photosensitive drum 21, a developing device 23, a cleaning unit (not shown), and a charge eliminating unit (not shown). ) Etc. Then, an image forming process (charging process, exposure process, developing process, transfer process, cleaning process) is performed on the photosensitive drum 21, and an image of each color is formed on the photosensitive drum 21. The image forming units for each color have substantially the same structure except that the color of the toner used is different.

  Each of the photosensitive drums 21Y, 21C, 21M, and 21K is driven to rotate counterclockwise in FIG. 1 by a drive motor (not shown). The surface of the photosensitive drum 21 is uniformly charged at the position of the charging unit (charging process). Thereafter, the surface of the photosensitive drum 21 reaches the irradiation position of the laser beam emitted from the exposure apparatus, and an electrostatic latent image is formed by exposure scanning at this position (exposure process).

Thereafter, the surface of the photosensitive drum 21 reaches a position facing the developing device 23, and the electrostatic latent image is developed at this position to form a toner image (developing process).
Thereafter, the surface of the photosensitive drum 21 reaches a position facing the intermediate transfer belt 18 and the first transfer bias roller (not shown), and the toner image on the photosensitive drum 21 is transferred to the intermediate transfer belt 18 at this position. (Primary transfer process). At this time, a small amount of untransferred toner remains on the photosensitive drum 21.

Thereafter, the surface of the photosensitive drum 21 reaches a position facing the cleaning unit, and untransferred toner remaining on the photosensitive drum 21 is collected at this position (cleaning step).
Finally, the surface of the photoconductive drum 21 reaches a position facing the static eliminator, and the residual potential on the photoconductive drum 21 is removed at this position.
Thus, a series of image forming processes performed on the photosensitive drum 21 is completed.

On the other hand, the intermediate transfer belt 18 onto which the toner images of the respective colors formed on the photosensitive drums 21Y, 21C, 21M, and 21K are transferred in a superimposed manner through the developing process reaches a position facing the secondary transfer roller 19. At this position, the secondary transfer backup roller sandwiches the intermediate transfer belt 18 between the secondary transfer roller 19 and forms a secondary transfer nip. The four-color toner images formed on the intermediate transfer belt 18 are transferred onto a recording medium P such as transfer paper conveyed to the position of the secondary transfer nip. At this time, untransferred toner that has not been transferred to the recording medium P remains on the intermediate transfer belt 18.
Thereafter, the intermediate transfer belt 18 reaches the position of the intermediate transfer cleaning unit. At this position, the untransferred toner on the intermediate transfer belt 18 is collected.
Thus, a series of transfer processes performed on the intermediate transfer belt 18 is completed.

Here, the recording medium P transported to the position of the secondary transfer nip is transported from a paper feed unit 26 disposed below the apparatus main body 100 via a paper feed roller 27 and a registration roller pair 28. It is a thing.
Specifically, a plurality of recording media P such as transfer paper are stored in the paper supply unit 26 in a stacked manner. When the paper feed roller 27 is driven to rotate counterclockwise in FIG. 1, the uppermost recording medium P is fed toward the registration roller pair 28.

  The recording medium P transported to the registration roller pair 28 temporarily stops at the position of the roller nip of the registration roller pair 28 whose rotation drive has been stopped. Then, the registration roller pair 28 is rotationally driven in time with the color image on the intermediate transfer belt 18, and the recording medium P is conveyed toward the secondary transfer nip. In this way, a desired color image is transferred onto the recording medium P.

Thereafter, the recording medium P on which the color image is transferred at the position of the secondary transfer nip is conveyed to the position of the fixing unit 20. At this position, the color image transferred on the surface is fixed on the recording medium P by heat and pressure generated by the fixing belt and the pressure roller. Thereafter, the recording medium P is discharged out of the apparatus as an output image.
Thus, a series of image forming processes in the image forming apparatus is completed.

Next, the developing device 23 which is a characteristic part of the present invention will be described. Here, description will be given focusing on one developing device, but this description applies to developing devices 23Y, 23C, 23M, and 23K having the same structure.
FIG. 2 is a perspective view of the developing device 23 provided with the developer guide member 40 according to the present invention. At one end of the developing device 23, the opening 47 of the developer guide member 40 is inserted and fitted into the protruding member 25 of the developing device 23 from above, so that the developer guide member 40 is attached to and detached from the developing device 23. It is fixed as possible. Developer guide member 40 has a lower opening portion of the communicating port to the upper portion of the opening and the developing device 23 as a toner replenishing port, a hollow base body 41 formed in a linear shape having a rectangular cross-section, the hollow substrate 41 has a U-shaped fitting portion 44 provided on the lower surface of 41, and an opening 47 is formed on both side surfaces of the fitting portion 44 to be fitted to the protruding member 25 of the developing device 23. A toner replenishing port 42 opened vertically upward is formed in the upper part of the hollow substrate 41, and an elastic member 45 is mounted on the top of the toner replenishing port 42. Further, a developer filling port 43 that is opened obliquely upward is formed substantially at the center of the side surface of the hollow substrate 41, and the developer filling port 43 is covered with a cap member 46 when not in use. Further, the lower portion of the hollow base 41 is also opened, and therefore, the toner or developer is transported by the conveying screw 24 disposed in the developer accommodating portion in the developing device 23 via the toner supply port 42 or the developer filling port 43. It is designed to be supplied to the part. The conveying screw 24 is a developer conveying member that includes a rotating shaft and a blade provided on the rotating shaft, and rotates to convey the developer in the axial direction.

As described above, the toner replenishing port 42 and the developer filling port 43 are provided in one developer guide member 40, and both the toner replenishment and the developer filling to the developing device 23 can be performed using the developer guide member. Therefore, the developing device can be downsized. Further, as shown in the figure, a developer including a toner supply passage for linear toner supply that extends in the vertical direction and a developer supply passage for developer supply that extends obliquely upward therefrom. The guide member 40 is preferably arranged perpendicular to the conveying screw 24 in the developing device 23. As a result, an inclined surface that can be a toner or developer reservoir is not formed in the toner / developer transport passage in the developer guide member 40, and the developer at the time of toner replenishment or at the time of developer replenishment. Accumulation and overflow of developer are prevented. Further, since it is not necessary to remove the sub hopper or the developing device, the developer can be charged even when the device is in use. The developer guide member 40 is made of, for example, a hard plastic material at a low cost.

  FIG. 3 shows a developer guide member 40 fixed to the developing device 23 and a sub hopper 50 joined to the upper portion thereof. The sub hopper 50 is detachably fixed to the developer guide member 40 by sliding and fitting the replenishment port opened vertically below the sub hopper to the toner replenishment port 42 of the developer guide member 40. . Each color toner bottle 32 is connected to a toner transport pipe 51 of the sub hopper 50 via a toner supply tube (not shown) which is a developer transport path member. The sub hopper 50 is configured to store the toner from the toner bottle 32. The stored toner is supplied to the developer guide member 40 disposed below, and then into the developing device 23 disposed below the toner guide member 40. It comes to be supplied.

  As shown in FIG. 4, the toner replenishing port 42 at the top of the developer guide member 40, which is a receiving port for toner from the sub hopper 50, has an inclined surface that is inclined with respect to the horizontal plane so as to be easily fitted to the sub hopper 50. An elastic member 45 is provided on the top thereof, so that the developer guide member 40 and the sub hopper 50 are brought into close contact with each other without any gap. The developer guide member 40 and the sub hopper 50 are fitted by sliding and fitting the developing device 23 provided with the developer guide member 40 with respect to the sub hopper 50 fixed in the image forming apparatus. . In addition, a developer filling port 43 that is opened obliquely upward is formed at the center of the hollow base 41 so that the developer can be easily filled, and the developer charged from the developer filling port 43 is in the middle. The toner is supplied to the developer container in the developing device 23 without accumulating. A cap member 46 that is removable when not in use is placed on the tip of the developer filling port 43 to prevent foreign matter from entering.

  As shown in FIG. 5, during normal use of the image forming apparatus, the front surface of the developing device 23 and the developer guide member 40, which are precision mechanical parts, are covered with a protective cover 60, thereby preventing malfunction of the device. . As shown in FIG. 6, the developer filling port 43 is covered and protected by a removable developer filling port cover 61. However, if the developer filling port cover 61 is removed as shown in FIG. 43 protrudes outward from an opening 62 formed in the protective cover 60. Here, in the developer filling port cover 61, the protrusion 64 provided on the upper part is fitted into the recess 63 formed in the opening 62, and the protrusion 65 provided on the lower part is formed on the protective cover 60. By fitting into the recess 66, the protective cover 60 is attached.

  By the way, since the two-component developer composed of toner and carrier is not filled in the developing device 23 at the time of shipment of the image forming apparatus, it is necessary to fill the developer at the time of installation. Further, it is necessary to replace the developer with a new one according to the life of the developer. At the time of maintenance, the used developer is discharged from a discharge port (not shown) provided on the back surface of the developing device 23, and a new one is released. It is necessary to fill the developer. When these developers are filled, the front cover (not shown) of the image forming apparatus is opened to expose the protective cover 60, and the developer filling port cover 61 is removed without having to remove the toner replenishing unit such as the sub hopper and the developing device. The cap member 46 can be removed to expose the developer filling port 43, from which the developer can be filled.

  As shown in FIGS. 7 and 8, the developer is charged and filled in the developing device 23 using a dedicated funnel 70 as a developer filling auxiliary member. The funnel 70 is a hollow member having a cylindrical portion 72, one end of the cylindrical portion 72 is formed as a developer receiving port 71 that is opened obliquely upward from the cylindrical portion 72, and the other end is formed as a developer discharging port 73. In addition, the cylindrical portion 72 is formed with a fitting portion 74 that is fitted over the developer filling port 43. When the fitting portion 74 of the funnel 70 is attached to the developer filling port 43 in a joined state, a part of the tip of the cylindrical portion 72 comes into contact with the inner wall of the developer guide member 40, and accordingly, the developer guide The passage in the member 40 is blocked from the cylindrical portion 72. As a result, when the developer is filled from the developer receiving port 71, it is possible to press the developer that is going to move up to the upper portion of the developer guide member 40 toward the toner replenishing port 42, and to the other part of the developer. While preventing intrusion, speeding up of filling is promoted. Further, by using the funnel 70, the developer can be introduced from a developer bottle or a bag-like container containing the developer.

  FIG. 9 is a plan sectional view of the developing device 23, and arrows 81 to 84 indicate the developer circulation path. In this developer circulation path, the developer is transported upward in the direction of arrow 81 by the rotation of the transport screw 24 on the left side in the drawing, and is transferred to the right transport screw 24 side on the back side of the developing device 23. The developer transported in the direction of the arrow 82 is transported in the direction of the arrow 84 in combination with the transport (extrusion) in the direction of the arrow 83, and is moved to the left transport screw 24 side on the front side of the developing device 23. It is. As shown in the figure, the position 80 of the opening of the hollow base 41 of the developer guide member 40 communicating with the developing device is located above the conveying screw 24 and outside the developer circulation path. Therefore, the toner or the developer is put into the position 80 outside the developer circulation path, which is a portion not filled with the developer, and continuously in the direction of the arrow 81 by the rotation of the conveying screw 24. Therefore, the developer can be replenished smoothly, and the toner and developer do not overflow from the developer receiving port 71.

  FIG. 10 is a longitudinal sectional view showing another embodiment of the developer guide member 40 according to the present invention. When the developer is filled in the developing device 23, the pressure in the developing device increases, and this pressure causes the developer to flow to the toner replenishing port 42 and the developer filling port 43, thereby causing the developer to scatter. . Therefore, in this developer guide member 40, an opening 90 is formed in the hollow base body 41 on the opposite side of the developer flow falling from the developer filling port 43 indicated by the arrow 92, and thereby, as indicated by the arrow 93. The pressure is released to the outside of the developer guide member 40 to prevent the developer from flowing to the toner replenishing port 42 and the developer filling port 43 and to prevent scattering. Further, since the pressure release filter 91 covers the opening 90, the internal pressure can be lowered by letting only air to the outside, and the toner scattering to the toner replenishing port or the developer filling port due to the increase of the internal pressure is prevented, The developer is not discharged from the developer guide member 40.

21 Photosensitive drum (image carrier)
23 Developing Device 24 Conveying Screw (Developer Conveying Member)
32 toner cartridge 40 developer guide member 41 hollow substrate 42 toner supply port 43 developer filling port 44 fitting portion 45 elastic member 46 cap member 47 opening portion 100 image forming apparatus

JP 2009-109527 A

Claims (8)

In an image forming apparatus comprising: an image carrier; a developing device that develops a latent image on the image carrier using a developer; and a toner bottle that contains toner to be supplied to the developing device.
A toner replenishing port for replenishing toner from the toner bottle; a communication port communicating with the developing device; and a developer filling port for charging a developer; and the communication from the toner replenishing port. A developer guide member having a toner supply passage extending vertically to the mouth and a developer supply passage connected to the toner supply passage so as to intersect obliquely from above ;
Developer guide member, the image forming apparatus, wherein the developer filling opening is provided for the developing unit so as to face the front side of the image forming apparatus.   2. The image forming apparatus according to claim 1, wherein the developer guide member has a linear hollow substrate, the toner supply port is formed in an upper portion of the hollow substrate, and the developer filling port is An image forming apparatus that protrudes from a side surface of a hollow substrate.   3. The image forming apparatus according to claim 1, wherein the developer guide member is disposed perpendicular to a developer transport member provided in the developing device. The image forming apparatus according to claim 1, wherein the communication port of the developer guide member communicating with the developing device communicates with a position outside a developer circulation path in the developing device. An image forming apparatus.   5. The image forming apparatus according to claim 1, wherein an opening for allowing air to escape to the outside when the developer is filled is opposed to the developer filling port of the developer guide member. An image forming apparatus provided at a position. The image forming apparatus according to any one of claims 1 to 5 when filling the developer, the developer filling auxiliary member is fitted to the developer filling opening, the developer by the developer filling auxiliary member An image forming apparatus, wherein a passage to the toner supply port in the agent guide member is blocked. 7. The image forming apparatus according to claim 6 , wherein the developer filling auxiliary member is a funnel. The image forming apparatus according to any one of claims 1 to 7 and characterized in that said toner supply port is formed to be inclined with respect to the horizontal plane, the elastic member is mounted on the upper part of the toner supply port Image forming apparatus.

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