JP2005049900A - Electrophotographic device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent toner-scattering in the case of detaching a process cartridge from an electrophotographic device main body, without the increase of a cost due to the installation of an additional member such as a sealing member, as for an electrophotographic device equipped with the process cartridge. <P>SOLUTION: The electrophotographic device is constituted of at least a developing device 14, and provided with the process cartridge 10 which is freely attached/detached to/from the electrophotographic device main body, a toner replenishing device 30 for replenishing the toner to the developing device through a toner inlet 48 and a shutter member 55 for opening/closing the toner inlet at the inside of a cartridge case 11 for the process cartridge. And when the process cartridge is attached to the device main body, the toner supply port 47 of the toner replenishing device is brought close to the toner inlet, on the other hand, when the process cartridge is detached from the device main body, the toner inlet is closed with the shutter member 55 at the inside of the cartridge case. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an image formed on an image carrier such as a photosensitive drum or a photosensitive belt by repeating charging, writing, developing, transferring, cleaning, etc., such as a laser copying machine, a laser printer, a laser facsimile, or a complex machine thereof. The present invention relates to an electrophotographic apparatus that performs recording on a recording medium such as paper.

  Conventionally, in this type of electrophotographic apparatus, in order to reduce the size and for convenience of maintenance, an image carrier and a developing device are provided in one cartridge case to constitute an integral process cartridge, Some process cartridges are detachable from the main body of the electrophotographic apparatus.

  In such a process cartridge, for example, as shown in FIG. 8, a toner receiving port 1 is provided, and toner from a toner replenishing device provided separately to the developing device in the process cartridge through the toner receiving port 1 is provided. There is something to replenish.

  With this type of process cartridge, for example, when it is taken out from the main body of the electrophotographic apparatus for maintenance, the toner inside may spill out through the toner receiving port 1, and there is a risk that the inside of the apparatus main body, the vicinity of the main body installation place, the user's hand, etc. there were.

  Therefore, for example, as shown in the figure, the shutter member 2 is provided, and both side edges 2a are placed under the ribs 3a of the cartridge case 3 so as to be slidable, and the coil spring 4 is placed in the frame portion 3b formed in the cartridge case 3 as well. The toner receiving port 1 is urged by the coil spring 4 in the closing direction, and the toner receiving port 1 is closed by the shutter portion 2b of the shutter member 2 outside the cartridge case 3.

  When the process cartridge is attached to the electrophotographic apparatus main body, the protrusion 2c provided on the shutter portion 2b is abutted against a member on the apparatus main body side and slides against the urging force to push the shutter member 2 open. On the other hand, when the toner is taken out from the apparatus main body, the toner receiving port 1 is closed again by the shutter member 2 by sliding based on the urging force.

Japanese Patent Laid-Open No. 08-286490 Japanese Patent Laid-Open No. 04-070779 JP 59-34568 A JP 62-299871 A

  However, in the conventional configuration as described above, since the toner receiving port 1 is closed by the shutter portion 2b of the shutter member 2 outside the cartridge case 3, when the process cartridge is attached to the main body of the electrophotographic apparatus, the toner receiving port 1 is provided. The peripheral edge is opened, and the toner from the toner replenishing device gets on the peripheral edge.

  Therefore, when the process cartridge is taken out from the apparatus main body, there is a problem that the shutter member 2 that is closed disposes the toner accumulated on the periphery of the toner receiving port 1 and the toner is scattered.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an electrophotographic apparatus including a process cartridge that is provided with at least a developing device. It is to prevent toner scattering when taking out the toner.

Therefore, the invention according to claim 1 is an electrophotographic apparatus according to an embodiment described with reference to the following drawings, for example:
A process cartridge 10 provided with at least a developing device 14 and detachably attached to the electrophotographic apparatus main body;
A toner replenishing device 30 for replenishing toner to the developing device 14 through a toner receiving port 48 of the process cartridge 10;
A shutter member 55 for opening and closing the toner receiving port 48 inside the cartridge case 11 of the process cartridge 10;
It is characterized by comprising.

  According to the first aspect of the present invention, when the process cartridge 10 is attached to the electrophotographic apparatus main body, the toner supply port 47 of the toner replenishing device 30 is brought close to the toner receiving port 48 of the process cartridge 10, and electrophotography is performed. When detached from the apparatus main body, the toner receiving port 48 is closed by the shutter member 55 inside the cartridge case 11.

The invention according to claim 2 is an electrophotographic apparatus according to claim 1, for example, as in the embodiment described with reference to the following drawings:
The shutter member 55 is slidably provided and urged in one of the sliding directions. When the process cartridge 10 is attached to or detached from the electrophotographic apparatus main body, the urging force is resisted in conjunction with the attaching / detaching operation. Alternatively, the toner receiving port 48 is opened and closed by sliding based on an urging force.

The invention according to claim 3 is the electrophotographic apparatus according to claim 2, for example, as in the embodiment described with reference to the following drawings:
The process cartridge 10 is provided with a cover member 57 that is attached after the shutter member 55 is attached and prevents the shutter member 55 from falling off.

According to a fourth aspect of the present invention, in the electrophotographic apparatus according to the first aspect, for example, as in the embodiment described with reference to the following drawings,
The shutter member 55 is pressed against the peripheral edge of the toner receiving port 48.

  Therefore, according to the present invention, the toner receiving opening is opened and closed by the shutter member inside the cartridge case of the process cartridge. Therefore, when the process cartridge is attached to the electrophotographic apparatus main body, the toner receiving opening is close to the process cartridge. A toner supply port of the toner replenishing device can be disposed, and toner can be prevented from adhering to the outer periphery of the toner receiving port.

  When the process cartridge is detached from the main body of the electrophotographic apparatus, the toner inlet is closed by the shutter member inside the cartridge case. Therefore, even if toner is attached inside the toner inlet, the shutter member opens and closes the toner. Thus, it is possible to prevent the toner from scattering out of the process cartridge without incurring a high cost by providing a separate member such as a seal member.

  According to the second aspect of the present invention, when the shutter member is slidably provided and urged in one direction in the sliding direction, and the process cartridge is attached to and detached from the electrophotographic apparatus main body, the shutter member is attached in conjunction with the attaching and detaching operation. Since the toner receiving port is opened and closed by sliding against the force or based on the urging force, the shutter member that opens and closes can be assembled very simply and easily, and there is no assembly error and the assembly time can be shortened. Efficiency can be improved.

  According to the third aspect of the present invention, since the cover member is attached to the process cartridge after the shutter member is attached to prevent the shutter member from coming off, the shutter member can be easily attached to the process cartridge without detachment or buckling of the urging member. Can be attached to.

  According to the invention described in claim 4, since the shutter member is pressed against the periphery of the toner receiving port, when the process cartridge is taken out from the main body of the electrophotographic apparatus, the toner receiving port is completely blocked with the shutter member, It is possible to reliably prevent the toner from spilling out from the toner receiving port even when the process cartridge is tilted or by vibrations when the collected process cartridge is carried.

The best mode of the present invention will be described below with reference to the drawings.
FIG. 1 is a block diagram showing the main part of an electrophotographic apparatus according to the present invention. In the figure, reference numeral 10 denotes a process cartridge, and reference numeral 30 denotes a toner supply device for supplying toner to the process cartridge 10.

  The process cartridge 10 is disposed in the cartridge case 11 in the vicinity of or in contact with the photosensitive drum 12 as an image carrier and the periphery of the photosensitive drum 12, and charging that uniformly charges the drum surface. A roller 13, a developing device 14 that visualizes the electrostatic latent image to form a toner image, and a cleaning device 15 that removes residual toner on the photosensitive drum 12 are provided.

  The developing device 14 includes conveying screws 20 and 21, a developing sleeve 22, a doctor blade 23, and a toner density sensor 24.

  Further, around the process cartridge 10, an optical writing device (not shown) that irradiates a laser beam a to form an electrostatic latent image on the photosensitive drum 12, and a toner image on the photosensitive drum 12 as a recording medium. A transfer roller 25 to be transferred and a charge removal device (not shown) that irradiates the charge removal light b to remove the remaining charge on the photosensitive drum 12 are provided.

  Then, along with the rotation of the photoconductive drum 12, first, the surface potential is averaged to the reference potential of 0 to -100V by irradiating the neutralizing light b with a neutralizing device (not shown). Next, charging is performed by the charging roller 13 to set the surface potential to −1100V.

  Then, the surface potential is set to 0 to −290 V only on the portion irradiated with the laser beam a by an optical writing device (not shown), and an electrostatic latent image is formed on the photosensitive drum 12. Thereafter, toner is attached by the developing sleeve 22 to which a bias potential of about −800 V is applied, and the electrostatic latent image is developed to form a toner image on the photosensitive drum 12.

  Next, as the photosensitive drum 12 rotates, the recording medium is fed from a paper feeding unit (not shown) in synchronization with the toner image on the photosensitive drum 12, and the toner image on the photosensitive drum 12 is transferred by the transfer roller 25. Transfer to the recording medium.

  Then, the recording medium after the toner image is transferred is separated from the photosensitive drum 12 and sent to a fixing device (not shown), where heat and pressure are applied to fix the transferred toner image, and then a paper discharge (not shown) is performed. Drain onto the stack.

  On the other hand, the photosensitive drum 12 after the transfer of the toner image is scraped off by the cleaning blade 26 of the cleaning device 15 to remove residual toner remaining on the surface thereof. Thereafter, the charge removal light b is irradiated again by a charge removal device (not shown) to prepare for the next image formation.

  The residual toner scraped off by the cleaning blade 26 is transported in the axial direction by the toner transport coil 27 and is put into a transport pipe 28 indicated by a two-dot chain line in the drawing, and freely falls in the transport pipe 28 to the developing device 14. By returning it, it can be recycled.

  Now, the developing sleeve 22 has a fixed shaft in which a 5-pole magnet is arranged, and has an outer peripheral surface covered with a non-magnetic pipe material. Then, as the pipe material rotates, the developer moves on the developing sleeve 22.

  The developer is a two-component type consisting of a small iron ball called a carrier and a toner. The developer is circulated while being agitated by the conveying screws 20 and 21, thereby giving the toner an electric charge and adhering to the carrier. The toner is carried to the surface and adheres to the surface of the photosensitive drum 12 by the action of electrostatic force.

  The developer generates image density defects and density unevenness unless the supply amount to the photosensitive drum 12 is constant. Therefore, the inflow amount of the developer is regulated by the doctor blade 23.

  Next, the toner replenishing device 30 that replenishes toner to the process cartridge 10 described above will be described. The toner replenishing device 30 is provided with a first hopper 31 and a second hopper 32.

  The first hopper 31 is formed integrally with a cradle 34 that accommodates the toner bottle 33. A toner introduction cover 36 is attached to the outside of the opening 35, and the toner introduction cover 36 is opened downward to form a toner supply port 37.

  On the other hand, the second hopper 32 is opposed to the toner supply port 37 of the first hopper 31 and opens upward to form a toner receiving port 38. The toner receiving port 38 has an introduction for guiding the toner. A path 39 is formed.

  The toner bottle 33 of the first hopper 31 is rotated by the motor 40 which is a driving source shown in FIG. 2, and the toner is dropped in the direction of arrow A in FIG. 1 and pushed up in the direction of arrow B by the push-up member 41 to open the opening 35. Pass through in direction C. The toner that has entered the toner introduction cover 36 falls into the second hopper 32 from the toner supply port 37 through the toner receiving port 38.

  The toner that has entered the second hopper 32 drops in the introduction path 39 in the direction of arrow D, is pushed up in the direction of arrow E by the push-up member 43 that rotates in the second hopper 32, and is a replenishment amount regulating member provided in the opening 44. It sends out in the F direction through 45 slits. The toner that has entered the toner introduction cover 46 enters the process cartridge 10 from the toner supply port 47 through the toner receiving port 48 and falls in the direction of arrow G.

  FIG. 2 shows a state where the first hopper 31 and the cradle 34 of the toner replenishing device 30 are pulled out of the electrophotographic apparatus main body. As can be seen from the figure, a shutter member 50 is provided on the outside of the toner introduction cover 36, and is normally urged in a direction to close the toner supply port 37 by an urging force such as a spring (not shown).

  A rib 50a is formed integrally with the shutter member 50, and when the first hopper 31 is pushed into the main body of the electrophotographic apparatus, the rib 50a abuts against a guide rib formed on the second hopper 32. At the same time as pressing, the shutter member 50 is moved in the direction of arrow H to open the toner supply port 37.

  On the other hand, the second hopper 32 is independently attached to the side plate of the electrophotographic apparatus main body using screws or the like, and is always fixed at a fixed position in the apparatus main body. A shutter member 51 is provided on the outer side of the toner introduction cover 46 of the second hopper 32, and is normally urged in a direction to close the toner supply port 47 by an urging force such as a spring (not shown).

  A rib 51a is integrally formed on the shutter member 51, and when the process cartridge 10 is mounted in the main body of the electrophotographic apparatus, the guide rib formed on the process cartridge 10 is brought into contact with the rib 51a. Then, along with the attachment, the shutter member 51 is moved in the direction of arrow I to open the toner supply port 47.

  In the present invention, as shown in FIG. 1, a separate shutter member 55 is also provided inside the cartridge case 11 of the process cartridge 10, and the toner receiving port 48 is opened and closed by the shutter member 55.

  As shown in FIG. 3, the shutter member 55 is formed by integrally forming a vertical edge 55b on one side of the top part 55a, a curved edge 55c on the other side, and an upward projecting part 55d on the top part 55a. A coil spring 56 is disposed on the curved edge 55c, one end of the coil spring 56 is brought into contact with the wall 55e on the end of the curved edge 55c, and the boss 55f of the wall 55e is press-fitted into the one end.

  Then, as shown in FIG. 4, the upward projecting portion 55 d is inserted into the toner receiving port 48, the shutter member 55 is inserted into the cartridge case 11 from the front, and the vertical edge 55 b is inserted into the guide step portion of the cartridge case 11. The curved edge 55c is placed on the guide edge 11b on 11a.

  Thereafter, a cover member 57 that covers the front side of the cartridge case 11 is attached to prevent the shutter member 55 from falling off. Then, the protrusion 57 a of the cover member 57 presses the free end of the coil spring 56, compresses the coil spring 56, and biases the cover member 57 in a direction to be always closed by the elasticity of the coil spring 56. Before the process cartridge 10 is mounted in the electrophotographic apparatus main body, the toner receiving port 48 is closed with the shutter member 55.

  As described above, the assembly of the shutter member 55 is very simple and easy. Therefore, there is no mistake in assembling and the assembling time can be shortened, so that the efficiency can be improved.

  Now, when the process cartridge 10 to which the shutter member 55 is attached is inserted into the electrophotographic apparatus main body, the upward projecting portion 55d comes into contact with the outer side of the toner introduction cover 46 of the second hopper 32, and the shutter member 55 is moved. Slide to open the toner receiving port 48.

  Thus, since the shutter member 55 is slid inside the process cartridge 10, even if toner is attached to the inside of the toner receiving port 48, the toner can be scraped off by the shutter member 55 that opens and closes, and the toner is processed in the process. There is no scattering outside the cartridge 10.

  Now, for example, as shown in FIGS. 5 and 6, the shutter member 55 is cut out at the center in the front-rear direction of the curved edge 55c to extend the elastic portion 55g downward, and the tip of the elastic portion 55g is below the curved edge 55c. The protrusion 55h may be formed on the lower surface of the tip of the elastic portion 55g.

  Then, L is defined from the upper surface of the top 55a to the tip of the protrusion 55h, and M is smaller than L from the inner peripheral surface of the toner receiving port 48 of the process cartridge 10 to the upper surface of the guide edge 11b as shown in FIG. To do.

  Then, when the shutter member 55 is assembled in the process cartridge 10, the elastic portion 55 g of the shutter member 55 pushes the guide edge portion 11 b of the process cartridge 10, and pushes the top portion 55 a of the shutter member 55 against the inner peripheral surface of the toner receiving port 48. Hit it.

  Thus, when the process cartridge 10 is taken out from the main body of the electrophotographic apparatus, the toner receiving port 48 is completely closed by the shutter member 55, and the recovered process cartridge 10 is carried even when the process cartridge 10 is tilted by mistake. Even when the vibration occurs, the toner can be reliably prevented from spilling out from the toner receiving port 48.

1 is a configuration diagram of a main part in an electrophotographic apparatus according to the present invention. In the electrophotographic apparatus, a toner replenishing device and a cradle integrated therewith are drawn out of the main body of the electrophotographic apparatus. FIG. 6 is a perspective view of a shutter member that opens and closes a toner receiving port and a coil spring that biases the shutter member in a process cartridge included in the electrophotographic apparatus. It is a perspective view showing attachment of a shutter member to a cartridge case of the process cartridge. It is a perspective view of the other example of a shutter member. It is a perspective view which shows the shutter member of other examples, and the coil spring which urges | biases it. It is a longitudinal cross-sectional view which shows the process cartridge which attaches the shutter member of another example. It is a perspective view which shows attachment of the shutter member to the cartridge case of the conventional process cartridge.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Process cartridge 11 Cartridge case 14 Developing device 30 Toner replenishing device 47 Toner supply port 48 Toner receiving port 55 Shutter member 57 Cover member

Claims (4)

A process cartridge provided with at least a developing device and detachably attached to the electrophotographic apparatus main body;
A toner replenishing device for replenishing toner to the developing device through a toner receiving port of the process cartridge;
A shutter member that opens and closes the toner receiving port inside a cartridge case of the process cartridge;
An electrophotographic apparatus comprising:   When the shutter member is slidably provided and urged in one of the sliding directions, and the process cartridge is attached to or detached from the electrophotographic apparatus main body, the urging force is resisted or attached in conjunction with the attaching / detaching operation. The electrophotographic apparatus according to claim 1, wherein the toner receiving opening is opened and closed by sliding based on a force.   The electrophotographic apparatus according to claim 2, wherein the process cartridge includes a cover member that is attached after the shutter member is attached and prevents the shutter member from falling off. The electrophotographic apparatus according to claim 1, wherein the shutter member is pressed against a peripheral edge of the toner receiving port.

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