JP2008176041A - Developing unit and image forming apparatus equipped therewith - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a developing unit which does not require a complicated metallic mold, in order to form a toner storage chamber adjacent to a developing device and which is made compact and restrains cost increase. <P>SOLUTION: In the developing unit X, the developing device 3a equipped with a developing roller inside and the toner storage chamber 3b, in which toner is temporarily stored so that the developing device 3a may be replenished with the toner are provided adjacent to each other in the lateral direction. The toner storage chamber 3b is surrounded and formed by a first wall member 31 arranged at one end in the longitudinal direction of the developing device 3a, and a second wall member 32, detachably mountable to the first wall member 31 and constituting the end on an opposite side to the developing device 3a of the developing unit X. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a developing unit and an image forming apparatus including the developing unit, and in particular, a developing unit and an image forming unit that can simplify the manufacturing process and reduce costs by devising the structure of the developing unit. It relates to the device.

As a conventional color image forming apparatus, there is a tandem type color image forming apparatus that uses an intermediate transfer member, and temporarily transfers four colors of toner onto the intermediate transfer member, and then transfers the full color image onto a transfer sheet at once. , Widely known. Further, the arrangement of each component (various units) in the tandem type color image forming apparatus using the intermediate transfer member is as follows: toner container, intermediate transfer unit, image forming unit (consisting of a developing unit and a drum unit) from the top of the apparatus. In many cases, the optical units are configured in this order.
In the case of a color image forming apparatus having such a configuration, for example, an intermediate transfer unit between the toner container and the developing unit is an obstacle to transport toner from the toner container to the developing unit. A device that bypasses and is provided with a pipe-shaped toner conveying means is known (for example, Patent Document 1). In this case, toner is conveyed from the toner container to the developing unit by bypassing the intermediate transfer unit by making the toner conveying means U-shaped or substantially L-shaped. When such a toner conveying means is used, if the positional relationship between the four toner containers and the four developing units differs for each color (four colors), the four toner conveying means are formed in the same shape, There is a problem that the manufacturing cost increases because the dual use cannot be achieved.
Further, if the four toner conveying units have the same shape and the positional relationship between the four toner containers and the four developing units is the same, there is a problem that the entire image forming apparatus becomes large.
As an improvement measure, Patent Document 1 proposes that a part of the pipe of the toner conveying means is formed by an elastic pipe. With this configuration, even if there is a slight shift in the positional relationship of each color between the toner container and the developing unit, the elastic pipe can be adjusted by elastic deformation, and image formation can be performed while suppressing an increase in manufacturing cost. It is possible to reduce the size of the apparatus.
JP 2002-148892 A

However, if the toner conveying means is constituted by a U-shaped or substantially L-shaped pipe to bypass the intermediate transfer unit, the image forming apparatus becomes larger in the width direction of the belt of the intermediate transfer unit. There was a problem. Therefore, the present inventors integrally form a toner conveyance path 201 penetrating the intermediate transfer unit 200 vertically in the intermediate transfer unit 200 as shown in FIG. 16 to convey the toner from the toner container 100 to the developing unit 300. In addition to performing linearly (A in FIG. 16), the toner conveying path 201 is formed integrally with the intermediate transfer unit 200, thereby successfully reducing the size of the entire image forming apparatus. In the developing unit 300 having this configuration, a developing device 320 provided with a developing roller and a toner storage chamber 310 for temporarily storing toner to supply toner to the developing device 320 are adjacent to each other in the lateral direction. The toner can be received from the toner container 100 above the intermediate transfer unit 200 into the toner storage chamber 310 through the toner transfer path 201 linearly above and below the intermediate transfer unit 200.
In this case, the toner storage chamber 310 includes an upper developing side toner receiving portion 301 that receives the toner by its own weight falling from the toner container 100 disposed at the upper side, and a developing side toner that supplies the toner to the developing device 320. And a supply unit so that the stored toner can be smoothly supplied to the developing device 320.
On the other hand, the side wall of the developing device 320 has a complicated shape in order to attach a developing roller or a bearing of a plurality of agitation means, and a conveying means (for example, a spiral) for conveying toner inside the developing device 320. It has become. Accordingly, as described above, the developing unit 320 and the developing unit 300 provided with the toner storage chamber 310 for temporarily storing the toner in order to supply toner to the developing unit 320 are adjacent to each other in the lateral direction. In this case, since the side wall of the developing device 320 having such a complicated shape becomes a wall body that separates the developing device 320 and the toner storage chamber 310, the development unit 300 is to be integrally formed as a whole. , A mold with a very complicated structure inside must be manufactured, the manufacturing process becomes complicated, and it is actually difficult to manufacture the mold, or the cost must be extremely expensive. There was a problem of becoming.
Accordingly, the present invention has been made in view of the above circumstances, and an object of the present invention is to make a compact and cost-effective, without requiring a complicated mold for forming a toner storage chamber adjacent to the developing device. It is to provide a developing unit capable of suppressing the rise of the image.

In order to achieve the above object, according to the present invention, a developing device provided with a developing roller and a toner storage chamber for temporarily storing toner to replenish the developing device are provided adjacent to each other in the lateral direction. The toner storage chamber includes an upper development-side toner receiving portion that receives the toner by its own weight drop directly or indirectly from a toner container disposed in the upper portion, and the toner in the developing unit. A developing-side toner supply section, and a first wall member disposed at one end in the longitudinal direction of the developing device, and attachable to and detachable from the first wall member. The developing unit is formed by being surrounded by a second wall member that constitutes an end opposite to the developing device.
With this configuration, a complicated mold is not required to form the toner storage chamber adjacent to the developing device, and the development unit can be made compact and the manufacturing cost can be suppressed.
Further, it is conceivable that the first wall member is integrally formed with one end portion in the longitudinal direction of the developing device. By integrally molding in this way, the number of parts can be reduced, and the manufacturing cost can be reduced.
The first wall member is integrally formed with one end of the developing device in the longitudinal direction, and is attached to and detached from the developing device side wall. However, it is conceivable that the container side wall body is detachable. With this configuration, the first wall member can be divided into the developing device side wall body and the container side wall body, the assembly process of the developing unit is simplified, and the manufacturing cost can be reduced. .
Further, it is conceivable that a position fixing member for fixing the position of the developing unit to the main body frame of the image forming apparatus including the developing unit is formed on the second wall member. With this configuration, even when the shape of the developing unit is changed in order to increase the printing speed of the image forming apparatus, the position of the position fixing member formed on the second wall member Thus, the development unit whose shape has been changed can be fixed at the same position on the main body frame, and the main body of the image forming apparatus can be shared.
An intermediate transfer unit is provided between the toner container and the developing unit, and the intermediate transfer unit is configured to transfer the toner from the toner container to the intermediate transfer side toner receiving unit, and to the developing side toner receiving unit. An intermediate transfer side toner supply unit that supplies toner; and a toner conveyance path that conveys the toner from the intermediate transfer side toner receiving unit to the intermediate transfer side toner supply unit. The toner can be received indirectly from the toner container via the intermediate transfer unit. With this configuration, the toner can be smoothly supplied from the toner container to the developing unit.
Further, the image forming apparatus can include the developing unit. As a result, the image forming apparatus can be reduced in size and cost.

  According to the present invention, there is provided a developing unit in which a developing unit provided with a developing roller and a toner storage chamber for temporarily storing toner for replenishing the developing unit are provided adjacent to each other in the lateral direction. The toner storage chamber includes an upper developing side toner receiving portion that receives the toner by its own weight drop directly or indirectly from a toner container disposed at an upper portion, and a developing side that supplies the toner to the developing unit. A first wall member disposed at one end in the longitudinal direction of the developing device, and attachable to and detachable from the first wall member. Is formed by being surrounded by a second wall member constituting the opposite end, thereby forming the toner storage chamber adjacent to the developing device. Without the need for complex mold in order, it is possible to suppress an increase in compactness and manufacturing cost of the developing unit.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings so that the present invention can be understood. The following embodiment is an example embodying the present invention, and does not limit the technical scope of the present invention.
[First Embodiment]
FIG. 1 is a sectional view of a tandem type color image forming apparatus having a developing unit as an example of the present invention, FIG. 2 is a perspective view showing a part of FIG. 1, and FIG. 3 is a perspective view of an intermediate transfer unit. 4 is a perspective view showing one end portion in the longitudinal direction of the developing unit according to the first embodiment of the present invention, FIG. 5 is a view in which the second wall member is removed from the developing unit shown in FIG. 4, and FIG. FIG. 7 is a perspective view showing a portion where the intermediate transfer side toner supply portion and the development side toner receiving portion are in contact with each other, FIG. 8 is a development view shown in FIG. It is a perspective view which shows the state by which the unit was fitted by the main body frame.
First, a schematic configuration of an image forming apparatus Z (see FIG. 1) including the developing unit X (see FIG. 4) according to an example of the present invention will be described.
As shown in FIG. 1, the image forming apparatus Z includes, from the top to the bottom, the toner container 1, the intermediate transfer unit 2, the developing unit X (see FIG. 2), the image forming unit 4 including the drum unit, the optical unit 5, and the like. It has. As shown in FIG. 2, the toner container 1, the intermediate transfer unit 2, and the developing unit X are arranged in this order from the top to the bottom.
As shown in FIG. 3, the intermediate transfer unit 2 includes an intermediate transfer portion 22 on which an intermediate transfer belt (not shown) travels, and a toner transport portion 23 adjacent thereto. The toner transfer unit 23 includes an intermediate transfer side toner receiving unit 24 that receives toner from the toner container 1 and an intermediate transfer side that supplies the toner to the developing side toner receiving unit 30 (see FIG. 4) of the developing unit X. A toner supply unit 25, the development-side toner receiving unit 30 and the intermediate transfer-side toner supply unit 25 are vertically connected, and the toner is supplied from the intermediate transfer-side toner receiving unit 24 to the intermediate transfer-side toner supply unit 25. A toner conveyance path 23a (see FIG. 7) for conveyance.

Next, the developing unit X according to the first embodiment of the present invention will be described.
As shown in FIG. 4, the developing unit X includes a developing unit 3a having a developing roller therein and a toner storage chamber 3b for temporarily storing toner in order to supply toner to the developing unit 3a. It is the developing unit provided adjacently. The toner storage chamber 3b includes an upper developing side toner receiving unit 30 that receives the toner from the intermediate transfer side toner supplying unit 25, and a developing side toner supplying unit 42 that supplies the toner to the developing unit 3a (see FIG. 5).
The toner storage chamber 3b is detachable from the first wall member 31 disposed at one end in the longitudinal direction of the developing unit 3a as shown in FIG. 5 and the first wall member 31 shown in FIG. Thus, the developing unit X is formed by being surrounded by a second wall member 32 that constitutes an end opposite to the developing device 3a. In this way, the developing unit X is formed by integrally forming the developing device 3a and the first wall member 31, and the second wall member 32 detachably coupled to the first wall member 31. Thus, the toner storage chamber 3b can be divided into the first wall member 31 and the second wall member 32, and a developing roller or a plurality of agitation means bearings on the first wall member 31 side, A complicated shape portion can be exposed on the side surface of the mold by a mounting hole for mounting a transporting means (for example, a spiral) for transporting toner inside the developing unit 3a. Since the mold can be an open mold, the mold can be simplified, and the manufacturing cost can be reduced based on the simplification of the manufacturing process. The first wall member 31 may be formed separately from the one end side wall member in the longitudinal direction of the developing device 3a. This will be described later as a second embodiment.
In the developing unit X according to this embodiment, the toner supplied to the toner storage chamber 3b temporarily stays in the toner storage chamber 3b and is extended to the toner storage chamber 3b. The toner is supplied from the toner storage chamber 3b to the developing device 3a by a spiral 40 (see FIG. 5).
With this configuration, a complicated mold is not required to form the toner storage chamber 3b disposed on the side wall of the longitudinal end of the developing unit 3a as described above, and the toner is removed. As a result of eliminating the need for a toner conveying pipe or the like protruding from the end of the developing unit X to supply the developing unit 3a, the toner accommodating chamber for supplying the toner to the developing unit 3a and the developing unit 3a. The developing unit X having 3b can be made compact.

Next, a connection portion between the development side toner receiving portion 30 of the toner storage chamber 3b of the development unit X and the intermediate transfer side toner supply portion 25 of the intermediate transfer unit 2 will be described.
As shown in FIG. 7, the intermediate transfer side toner supply unit 25 is formed so as to supply the toner directly below, and at that portion, the intermediate transfer side toner supply unit 25 contacts the development side toner receiving unit 30 of the toner storage chamber 3b. Connected. Further, since the toner storage chamber 3b is formed downward from the intermediate transfer side toner supply unit 25, the toner is transferred from the intermediate transfer side toner supply unit 25 by its own weight to the lower toner storage chamber 3b. Will be supplied to.
In this case, an intermediate transfer unit that does not have the toner conveyance unit 23 may be configured to convey toner by its own weight from the toner container 1 to the developing unit X using a known conveyance unit (flexible tube or the like). Of course, the developing-side toner receiving portion 30 of the toner storage chamber 3b may be directly connected to the toner container 1.

Next, a mechanism in which one end portion of the developing unit X in the longitudinal direction is fixed with respect to the main body frame 7 (see FIG. 8) of the image forming apparatus Z will be described.
As shown in FIG. 8, the main body frame 7 is formed with a substantially U-shaped groove 8 opened upward. Further, as shown in FIG. 4, the developing unit X is integrally provided with a fitting portion 33 fitted in the substantially U-shaped groove 8 on the side wall of one end portion of the developing device 3a. As shown in FIG. 8, the fitting portion 33 is fitted into the substantially U-shaped groove 8.
Further, the developing unit X is in contact with the intermediate transfer unit 2 as shown in FIG. 7, and the fitting portion 33 is formed in the substantially U-shaped groove 8 by the intermediate transfer unit 2 fixed in position. Pressed against the bottom. As a result, one end of the developing unit X in the longitudinal direction is fixed to the main body frame 7.

[Second Embodiment]
Next, the developing unit Y according to the second embodiment of the present invention will be described.
The difference from the first embodiment is that the first wall member is integrally formed with one end of the developing device in the longitudinal direction, and is detachable from the developing device side wall. It is a point provided with the container side wall body which can also be attached or detached with respect to the said 2nd wall body. Needless to say, like the developing unit X, the developing unit Y is provided in the image forming apparatus Z.
FIG. 9 is a perspective view showing one end portion in the longitudinal direction of the developing unit according to the second embodiment of the present invention, and FIG. 10 is a diagram in which the second wall member is removed from the developing unit shown in FIG. 11 is a view in which the container side wall is removed from the developing unit shown in FIG. 10, FIG. 12 is a single view of the container side wall, FIG. 13 is a perspective view of the second wall member in the second embodiment, and FIG. FIG. 13 is a perspective view when FIG. 13 is viewed from the back side, and FIG. 15 is a schematic view showing a state where the developing unit shown in FIG. 9 is fitted to the main body frame.
As shown in FIG. 9, in the developing unit Y, a developing device 3c having a developing roller therein and a toner storage chamber 3d for temporarily storing the toner to replenish the developing device 3c are arranged in the horizontal direction. It is the developing unit provided adjacently. The toner storage chamber 3d supplies the toner to the upper developing side toner receiving unit 30 that receives the toner from the intermediate transfer side toner supplying unit 25 (see FIGS. 3 and 7) and the developing unit 3c. And a development-side toner supply unit 42 (see FIG. 10).
As shown in FIG. 10, the toner storage chamber 3d is detachably attached to the first wall member 34 disposed at one end in the longitudinal direction of the developing device 3c and the first wall member 34, and is connected to the developing unit. It is formed by being surrounded by a second wall member 35 (see FIG. 13) that constitutes an end portion on the side opposite to the Y developing device 3c. The first wall member 34 is detachably attached to the developing device side wall 34a (see FIG. 11) formed integrally with one end of the developing device 3c in the longitudinal direction, and the developing device side wall 34a. And a container side wall 34b (see FIG. 12). That is, the container side wall 34b can be attached to and detached from the developing device side wall 34a, and can also be attached to and detached from the second wall member 35.
In this way, the first wall member 34 of the developing unit Y is integrally formed with one end of the developing device 3c in the longitudinal direction, the developing device side wall 34a, the developing device side wall 34a and the second wall. The container side wall 34b detachably attachable to the wall member, the first wall member 34 can be divided into the developer side wall 34a and the container side wall 34b. The assembly process of the developing unit Y to which the developing roller of the developing device 3c or the bearings of a plurality of stirring means, the transporting means (for example, spiral) for transporting the toner inside the developing device 3c, etc. is simplified is simplified, and the manufacturing cost is reduced. can do.
The container side wall 34b may be integrally formed with the developer side wall 34a.

Further, the second wall member 35 includes fitting portions 37b and 38b of the second wall member 35 shown in FIG. 14, and fitting portions 37a at one end in the longitudinal direction of the developing device 3c shown in FIG. And 38a are fixed to the developing device side wall 34a integrally formed at one end in the longitudinal direction of the developing device 3c. Further, the second wall member 35 is screwed to a screw hole 41a (see FIG. 10) of the developing device side wall 34a by a screw hole 41b (see FIG. 14). Thus, the second wall member 35 is positioned on the developing device 3c by the fitting of the fitting portions 38a and 38b.
Further, as shown in FIG. 9, the substantially U-shaped groove 8 (see FIG. 15) formed in the main body frame 7 and opened upward is formed in the second wall member 35 of the toner storage chamber 3d. The fitting portion 36 to be fitted to is integrally formed.
With this configuration, even when the shape of the developing unit 3d is changed in order to increase the printing speed of the image forming apparatus, the fitting portion formed on the second wall member 35 By changing the position 36, the development unit whose shape has been changed can be fixed in the substantially U-shaped groove 8 of the main body frame 7, and the image forming apparatus main body can be shared. .

Next, a mechanism in which one end portion of the developing unit Y in the longitudinal direction is fixed with respect to the main body frame 7 (see FIG. 15) of the image forming apparatus Z will be described.
As shown in FIG. 15, the main body frame 7 is formed with the substantially U-shaped groove 8 opened upward. Further, as shown in FIG. 9, the second wall member 35 positioned in the developing unit 3c is provided with the fitting portion 36 to be fitted into the substantially U-shaped groove 8. As described above, the fitting portion 36 is fitted into the substantially U-shaped groove 8.
Further, the developing unit Y is in contact with the intermediate transfer unit 2 in the same manner as the developing unit X in contact with the intermediate transfer unit 2 as shown in FIG. 2, the fitting portion 36 is pressed against the bottom of the substantially U-shaped groove 8. As a result, one end of the developing unit Y in the longitudinal direction is fixed to the main body frame 7.

1 is a cross-sectional view of a tandem color image forming apparatus including a developing unit according to an example of the present invention. The perspective view showing a part of FIG. The perspective view of an intermediate transfer unit. FIG. 3 is a perspective view showing one end portion in the longitudinal direction of the developing unit according to the first embodiment of the present invention. The figure which removed the 2nd wall member from the image development unit shown in FIG. The single-piece figure of the 2nd wall member in 1st Embodiment. FIG. 4 is a perspective view showing a portion where an intermediate transfer side toner supply unit and a development side toner receiving unit are in contact with each other. FIG. 5 is a perspective view showing a state in which the developing unit shown in FIG. 4 is fitted to a main body frame. The perspective view which shows the one end part of the longitudinal direction of the developing unit which concerns on the 2nd Embodiment of this invention. The figure which removed the 2nd wall member from the image development unit shown in FIG. The figure which removed the container side wall body from the image development unit shown in FIG. Single item drawing of container side wall body. The perspective view of the 2nd wall member in 2nd Embodiment. The perspective view at the time of seeing FIG. 13 from the back side. Schematic which shows the state by which the image development unit shown in FIG. 9 was fitted by the main body frame. 1 is a schematic diagram illustrating an example of a part of an image forming apparatus.

Explanation of symbols

X, Y ... developing unit Z ... image forming apparatus 1 ... toner container 2 ... intermediate transfer units 3a, 3c ... developer 3b, 3d ... toner storage chamber 7 ... main body frame 8 ... substantially U-shaped grooves 31, 34 ... 1 wall member 32, 35 ... 2nd wall member 33, 36 ... fitting part

Claims (6)

A developing unit having a developing roller provided therein and a toner storage chamber for temporarily storing toner in order to replenish the developing unit with toner;
The toner storage chamber includes an upper developing side toner receiving portion that receives the toner directly or indirectly by its own weight drop from a toner container disposed at an upper portion, and a developing side toner supplying portion that supplies the toner to the developing device And a first wall member disposed at one end in the longitudinal direction of the developing device, and attachable to and detachable from the first wall member, the developing unit being opposite to the developing device. A developing unit characterized in that it is formed by being surrounded by a second wall member that constitutes an end of the developing unit.   The developing unit according to claim 1, wherein the first wall member is integrally formed with one end of the developing device in the longitudinal direction.   The first wall member is integrally formed with one end portion in the longitudinal direction of the developing device, and the developing device side wall body is detachable from the developing device side wall body and is also detachable from the second wall body. The developing unit according to claim 1, comprising a detachable container side wall body.   4. The position fixing member for fixing the position of the developing unit to a main body frame of an image forming apparatus including the developing unit is formed on the second wall member. Development unit. An intermediate transfer unit is provided between the toner container and the developing unit;
The intermediate transfer unit includes an intermediate transfer side toner receiving unit that receives the toner from the toner container, an intermediate transfer side toner supply unit that supplies the toner to the development side toner receiving unit, and an intermediate transfer side toner receiving unit. A toner transport path for transporting the toner to the intermediate transfer side toner supply unit,
The developing unit according to claim 1, wherein the toner storage chamber receives the toner indirectly from the toner container via the intermediate transfer unit. An image forming apparatus comprising the developing unit according to claim 1.

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