JP2008256895A - Developer storage device and image forming apparatus using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a developer storage device designed so that image persistence of developer is prevented by suppressing generation of frictional heat of a bearing part by a simple configuration without increasing costs, and to provide an image forming apparatus. <P>SOLUTION: The developer storage device includes: a developer storage container 1a storing developer; a rotating member 5 disposed penetrating through the developer storage container 1a; and the bearing part 3a supporting the rotating member 5 in the developer storage container 1 so that the member 5 is rotatable. The rotating member 5 has a screw fixing part 5c being a portion projecting toward the inside of the developer storage container 1a and formed smaller in diameter than the bearing part 3a. The rotating member 5 is sealed by a sealing member 6 disposed in close contact with the outer peripheral face of the screw fixing part 5c and the internal face of the developer storage container 1a. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a developer storage device used in an image forming apparatus such as an electrophotographic copying machine or a printer, and an image forming apparatus using the same.

  In an image forming apparatus such as an electrophotographic copying machine or printer, a photosensitive member as an image carrier is charged by a charger, and light is applied to the charged photosensitive member according to image information to form a latent image. The latent image is developed by a developing device, and the developed toner image is transferred to a sheet material or the like to form an image. Here, since the toner (developer) used for development is powder, it is supplied into the apparatus by a toner cartridge (developer storage container).

  FIG. 7 is a cross-sectional view of an end portion of a conventional developer storage container. In this type of developer storage container, as shown in FIG. 7, the developer in the container 100 is agitated so as to have a rotating member 101. Since the rotating member 101 in the container 100 is driven from the outside of the container 100, the rotating member 101 penetrates the container 100 and is supported by the bearing 102. If it enters, there is a risk of hindering smooth rotation. For this reason, it is necessary to securely seal the developer at this penetrating portion. Therefore, conventionally, the diameter of the hole 104 of the sealing member 103 such as sponge or rubber at the penetrating portion is reduced so that the sealing member 103 is strongly adhered to the rotating member.

Further, as described in, for example, (Patent Document 1), an auxiliary container having a space in the vertically lower part of the rotating member is provided in close contact with the developer storage container so as to cover the wall surface of the developer storage container, and the developer storage A developer storage container configured to prevent the developer from entering between the bearing and the rotating member by storing the developer leaked from the seal member on the container wall surface in the auxiliary container and discharging it to the outside by the hose. Proposed.
Japanese Utility Model Publication No. 1-90050

  However, when the auxiliary container is provided in the developer storage container as described in (Patent Document 1), there is a problem that the developer storage container is enlarged. In addition, the number of parts such as an auxiliary container and a hose for releasing the developer in the auxiliary container to the outside is large, the structure becomes complicated, and the cost increases.

  Further, as described above, when the seal member 103 is tightly adhered to the rotating member 101, the torque at which the rotating member 101 is rotated increases or the rotational friction increases, so that the temperature of the bearing 102 portion increases, and the development. Problems such as burning of the agent occur.

  Accordingly, in the present invention, there is provided a developer storage device and an image forming apparatus using the same, in which the generation of frictional heat at the bearing portion is suppressed and developer burn-in is prevented without increasing the cost with a simple configuration. The purpose is to do.

  In order to solve the above problems, a developer storage device of the present invention includes a developer storage container for storing a developer, a rotating member provided through the developer storage container, and the rotating member for storing the developer. A developer storage device having a bearing portion rotatably supported by a container, wherein the rotating member is formed so that a portion protruding inside the developer storage container has a smaller diameter than the bearing portion, and is formed to have this small diameter. It is sealed by a seal member that is in close contact with the outer peripheral surface of the portion and the inner surface of the developing storage container.

  According to the present invention, the seal member is brought into close contact with the outer peripheral surface of the portion formed to have a small diameter so that the linear velocity of the close contact portion of the seal member is reduced, so that generation of frictional heat can be suppressed. In addition, a developer storage device and an image forming apparatus using the developer storage device can be obtained that suppresses the generation of frictional heat at the bearing portion and prevents the image sticking of the developer without increasing the cost with a simple configuration.

  A first invention of the present application is a developer storage container for storing a developer, a rotating member provided through the developer storing container, and a bearing that rotatably supports the rotating member on the developer storing container. A rotating member is formed such that a portion protruding inside the developer storage container has a smaller diameter than the bearing portion, and the outer peripheral surface of the portion formed in the small diameter and the developer storage container The developer storage device is sealed with a seal member in close contact with an inner surface. According to the present invention, the seal member is brought into close contact with the outer peripheral surface of the portion formed to have a small diameter so that the linear velocity of the close contact portion of the seal member is reduced, so that generation of frictional heat can be suppressed. In addition, a developer storage device and an image forming apparatus using the developer storage device can be obtained that suppresses the generation of frictional heat at the bearing portion and prevents the image sticking of the developer without increasing the cost with a simple configuration.

  According to a second invention of the present application, the rotating member is formed to have a smaller diameter from the position inside the developer storage container than the inner surface of the developer storage container around the bearing portion, and the seal member is arranged around the bearing portion. A developer storage device characterized in that the developer storage container is tightly sealed between an inner surface of a developer storage container and an outer peripheral surface of a portion formed to have a small diameter. According to the present invention, the seal member is curved when it crosses from the inner surface of the developer storage container around the bearing portion to the outer peripheral surface of the portion formed to have a small diameter, and the inner edge portion of the seal member is formed to have this small diameter. The contact pressure can be sufficiently secured even with a small pressing force. Therefore, the generation of frictional heat can be further suppressed, and the developer burn-in can be prevented.

  A third invention of the present application is a developer storage device in which the rotating member is formed by a tapered surface between a portion held by the bearing portion and a portion formed in a small diameter, and the seal member is Since surface contact is made on this tapered surface, a higher sealing effect can be exhibited.

  The fourth invention of the present application is a developer storage device in which the seal member is a developer storage device whose inner peripheral tip is in contact with the rotating member on the tapered surface, and the inner peripheral tip is in surface contact on the tapered surface. By coating this contact surface of the seal member, it is possible to achieve a long life and improve slidability.

  According to a fifth aspect of the present invention, the inner diameter of the seal member is φA, the inner diameter of the bearing portion is φB, and the most adhesive that adheres between the seal member and the inner surface of the developer storage container around the bearing portion. A developer storage device characterized in that φA <φB <φC when the inner diameter is φC, and the rotation of the rotating member is hindered by the adhesive so that the adhesive does not contact the rotating member. Can be prevented.

  A sixth invention of the present application is an image forming apparatus including the developer storage device described above, and prevents the developer from being burned by suppressing the generation of frictional heat in the bearing portion without increasing the cost by a simple configuration. An image forming apparatus is obtained.

  Embodiments of the present invention will be described below with reference to the drawings.

(Embodiment 1)
1 is a cross-sectional view of an end portion of a developer storage device in Embodiment 1 of the present invention, FIG. 2 is an exploded perspective view of the end portion of FIG. 1, and FIG. 3 shows a relationship between a seal member, a container, and an adhesive. It is sectional drawing.

  As shown in FIGS. 1 and 2, a developer storage device 1 according to Embodiment 1 of the present invention is mounted on an image forming apparatus, and is a cylindrical container body constituting a developer storage container 1a. 2 and a lid member 3 that closes the end of the container body 2, a screw 4 that rotates inside the developer storage container 1a, a rotating member 5 that is connected to the screw 4 and rotates together with the screw 4, and a seal member 6 And have. The lid member 3 includes a bearing portion 3a that penetrates the rotation member 5 and supports the rotation member 5 so as to be rotatable.

  The rotating member 5 is formed with a gear portion 5a for driving by a driving means (not shown), a cylindrical shaft portion 5b that slides on the inner surface of the bearing portion 3a, and a step having a smaller diameter than the shaft portion 5b. It is comprised from the column-shaped screw fixing | fixed part 5c. As shown in FIG. 1, the screw fixing portion 5c is in a position protruding to the inside of the developer storage container 1a in a state where the developer storage device 1 is assembled.

  As shown in FIG. 2, the seal member 6 is a member formed by cutting out a plate material such as sponge or rubber into a disk shape. Further, a through hole 6 a through which the screw fixing portion 5 c of the rotating member 5 passes is formed at the center of the seal member 6. The inner surface of the through hole 6a is in close contact with the outer peripheral surface of the screw fixing portion 5c. The seal member 6 is bonded to the lid member 3 with an adhesive 7.

  Here, as shown in FIG. 3, the adhesive 7 has an inner diameter of the through hole 6 a of the seal member 6 as φA, an inner diameter of the bearing portion 3 a as φB, and an innermost diameter of the adhesive 7. When φC, it is applied so that φA <φB <φC. Thereby, the adhesive 7 is prevented from coming into contact with the rotating member 5, and the adhesive 7 can prevent the rotation of the rotating member 5 from being inhibited.

  As described above, in the developer storage device 1 according to the present embodiment, the seal member 6 is tightly sealed with the outer peripheral surface of the screw fixing portion 5c formed with a smaller diameter than the bearing portion 3a. The linear velocity of the contact portion of the is slow. Therefore, generation of frictional heat can be suppressed, and generation of frictional heat of the bearing portion 3a can be suppressed and burn-in of the developer can be prevented without increasing the cost with a simple configuration.

(Embodiment 2)
FIG. 4 is a cross-sectional view of the end portion of the developer storage device according to the second embodiment of the present invention.

  As shown in FIG. 4, the developer storage device 10 according to the second embodiment of the present invention is a gear portion that is driven by a driving means (not shown) instead of the rotating member 5 of the developer storage device 1 shown in FIG. Rotating member 11 including 11a, a cylindrical shaft portion 11b that slides on the inner surface of bearing portion 3a, and a cylindrical screw fixing portion 11c that is formed with a step smaller in diameter than shaft portion 11b. This is a configuration provided.

  In the rotating member 11, the screw fixing portion 11 c is formed from a position inside the developer storage container 1 a relative to the inner surface of the developer storage container 1 a around the bearing portion 3 a, that is, the inner surface of the lid member 3. Thereby, the seal member 6 is curved when it crosses from the inner surface of the lid member 3 to the outer peripheral surface of the screw fixing portion 11c, and is not an inner surface of the through hole 6a of the seal member 6, but an inner edge portion of the seal member 6. Since 6b contacts this screw fixing | fixed part 11c, contact pressure can fully be ensured with a small pressing force.

  Thereby, in the developer storage device 10 in the present embodiment, the generation of frictional heat can be further suppressed, and the burn-in of the developer can be prevented.

(Embodiment 3)
FIG. 5 is a cross-sectional view of the end portion of the developer storage device in Embodiment 3 of the present invention.

  As shown in FIG. 5, the developer storage device 20 according to the third embodiment of the present invention is a gear portion that is driven by a driving means (not shown) instead of the rotating member 5 of the developer storage device 1 shown in FIG. Rotating member 21 composed of 21a, a cylindrical shaft portion 21b that slides on the inner surface of bearing portion 3a, and a cylindrical screw fixing portion 21c formed with a step smaller in diameter than shaft portion 21b. This is a configuration provided.

  In the rotating member 21, a tapered surface 21d is formed between the shaft portion 21b held by the bearing portion 3a and the screw fixing portion 11c formed to have a small diameter. As a result, the seal member 6 comes into contact with the rotating member 21 by the edge portion 6b and also comes into surface contact with the rotating member 21 at the tapered surface 21d.

  Accordingly, as described above, the contact pressure can be sufficiently secured to the edge portion 6b with a smaller pressing force, and the taper surface 21d can exhibit a higher sealing effect, so the edge portion 6b. Thus, it is possible to prevent the developer that has exceeded the flow-out from flowing into the bearing portion 3a.

(Embodiment 4)
FIG. 6 is a cross-sectional view of the end portion of the developer storage device in Embodiment 4 of the present invention.

  As shown in FIG. 6, the developer storage device 30 according to the fourth embodiment of the present invention includes a gear unit that is driven by a driving unit (not shown) instead of the rotating member 21 of the developer storage device 20 shown in FIG. 5. Rotating member 31 composed of 31a, a cylindrical shaft portion 31b sliding on the inner surface of bearing portion 3a, and a cylindrical screw fixing portion 31c formed with a step having a smaller diameter than shaft portion 31b. This is a configuration provided.

  In the rotating member 31, a tapered surface 31d having an angle formed with the screw fixing portion 31c is larger than that of the rotating member 21 in FIG. The seal member 6 is in surface contact with the rotary member 31 on the tapered surface 31d at the inner peripheral tip of the through hole 6a.

  As described above, in the developer storage device 30 according to the present embodiment, the surface 6c of the inner peripheral tip of the seal member 6 is mainly in surface contact with the tapered surface 31d, not the inner surface of the through hole 6a of the seal member 6. . That is, in the manufacturing process of the seal member 6, the contact is made not on the inner surface of the through-hole 6 a serving as a cut surface but on the surface 6 c that can be coated. It is possible to improve the performance.

  The developer storage device of the present invention is useful as a device for supplying a photoreceptor to an image forming apparatus such as an electrophotographic copying machine or printer. In particular, the present invention is suitable as a developer storage device that prevents the developer from being burned by suppressing the generation of frictional heat in the bearing portion without increasing the cost with a simple configuration.

Sectional drawing of the edge part of the developer storage apparatus in Embodiment 1 of this invention 1 is an exploded perspective view of the end of FIG. Sectional drawing which shows relationship between sealing member and container and adhesive Sectional drawing of the edge part of the developer storage apparatus in Embodiment 2 of this invention Sectional drawing of the edge part of the developer storage apparatus in Embodiment 3 of this invention Sectional drawing of the edge part of the developer storage apparatus in Embodiment 4 of this invention Sectional view of the end of a conventional developer storage container

Explanation of symbols

1, 10, 20, 30 Developer storage device 1a Developer storage container 2 Container body 3 Lid member 3a Bearing portion 4 Screw 5, 11, 21, 31 Rotating member 5a, 11a, 21a, 31a Gear portion 5b, 11b, 21b , 31b Shaft part 5c, 11c, 21c, 31c Screw fixing part 6 Seal member 6a Through hole 6b Edge part 6c Surface 7 Adhesive 21d, 31d Tapered surface

Claims (6)

A developer storage container having a developer storage container for storing the developer, a rotating member provided through the developer storage container, and a bearing portion rotatably supporting the rotating member on the developer storage container. A device,
The rotating member includes a seal member in which a portion protruding to the inside of the developer storage container is formed to have a smaller diameter than the bearing portion, and the outer peripheral surface of the portion formed in the small diameter and the inner surface of the developer storage container are in close contact with each other A developer storage device characterized in that the developer storage device is sealed. The rotating member is formed to have a smaller diameter from the position inside the developer storage container than the inner surface of the developer storage container around the bearing portion,
2. The developing device according to claim 1, wherein the seal member seals tightly between an inner surface of a developer storage container around the bearing portion and an outer peripheral surface of a portion formed in the small diameter. Agent storage device. The developer storage device according to claim 2, wherein the rotating member is formed by a tapered surface between a portion held by the bearing portion and a portion formed to have a small diameter. The developer storage device according to claim 3, wherein the seal member has an inner peripheral tip that contacts the rotating member on the tapered surface. The inner diameter of the seal member is φA, the inner diameter of the bearing portion is φB, and the innermost diameter of the adhesive to be bonded between the seal member and the inner surface of the developer storage container around the bearing portion is 5. The developer storage device according to claim 1, wherein φA <φB <φC when φC is satisfied. An image forming apparatus comprising the developer storage device according to claim 1.

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