JP2004252141A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To miniaturize an image forming apparatus by efficiently arranging a large-capacity toner cartridge. <P>SOLUTION: The image forming apparatus has an apparatus body 11 on which an exposure unit 13, a developing unit 14 and the toner cartridge 12 are mounted, and housing space in which the toner cartridge is housed is regulated on the apparatus body 11, and also the exposure unit is arranged on the upside of the toner cartridge and the developing unit is positioned on the side of the toner cartridge adjacently to the housing space. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an image forming apparatus such as a copying machine, a printer, or a facsimile using an electrophotographic process, and particularly to various process units (for example, an exposure unit (laser scanner unit: LSU), a toner cartridge, and a developing unit). This is related to the layout (arrangement).
[0002]
[Prior art]
2. Description of the Related Art Some image forming apparatuses using an electrophotographic process are assembled for each of various process units, and some of these process units can be removed as necessary (separable units). For example, in an image forming apparatus, an exposure unit (laser scanner unit: LSU) used when forming an electrostatic latent image on a photosensitive drum, and an electrostatic latent image on the photosensitive drum are developed with a developer (toner). A developing unit for converting the toner image into a toner image and a toner cartridge for supplying toner to the developing unit are provided, and the user replaces the toner cartridge as needed.
[0003]
Generally, the capacity of a toner cartridge is a capacity that can perform printing (image formation) of about 1,000 to 3,000 sheets, and when printing is performed to this extent, it is necessary to replace the toner cartridge. With such a small-capacity toner cartridge, the toner cartridge can be disposed outside the frame of the image forming apparatus main body so that the toner cartridge can be easily replaced, but the toner cartridge is frequently replaced.
[0004]
On the other hand, there is also an image forming apparatus in which each process unit is integrated. In such an integrated unit, in addition to the toner cartridge, a system in which parts such as a developing unit together with a photosensitive drum unit are replaced as consumables is adopted. I have. However, in such an integrated unit, since there are parts to be replaced other than the toner cartridge, the cost of printing per sheet includes the cost of parts other than the toner cartridge, so the cost is high. It will be.
[0005]
Accordingly, the life of the units other than the toner cartridge is prolonged, the number of replacements of the units other than the toner cartridge is reduced, and the replacement is not performed until the life of the image forming apparatus itself. It has been proposed that only replenishment be performed.
[0006]
Further, in order to reduce the number of replacements of the toner cartridge itself, the capacity of the toner cartridge itself may be increased. However, if the capacity of the toner cartridge is increased, the size of the image forming apparatus itself increases. .
[0007]
In order to increase the capacity of the toner cartridge, for example, a plurality of process units including a photoconductor and a developing unit are provided on a main body in which a lower main body and an upper main body are rotatably connected to each other. In some cases, a toner cartridge is attached to the upper surface opening of the toner cartridge, and an opening for projecting the toner cartridge is formed in the upper main body. The volume is increased (see Patent Document 1).
[0008]
[Patent Document 1]
JP-A-5-19548 (paragraphs (0011) to (0014), FIG. 1)
[0009]
[Problems to be solved by the invention]
When the capacity of the toner cartridge is simply increased, other process units such as the developing unit and the LSU are affected, and the image forming apparatus is inevitably increased in size.
[0010]
In the image forming apparatus described in Patent Literature 1, a plurality of process units including a photoreceptor and a developing unit are provided in an apparatus main body, and a toner cartridge is mounted on an upper opening of a toner container. Although the toner cartridge protrudes from the opening, thereby increasing the capacity of the toner cartridge, since the toner cartridge protrudes from the upper main body, the height of the main body of the image forming apparatus is increased by the protruding amount. As a result, when the capacity of the toner cartridge is increased, there is a problem that the size of the image forming apparatus is correspondingly increased.
[0011]
An object of the present invention is to provide a small-sized image forming apparatus in which a large-capacity toner cartridge is efficiently arranged.
[0012]
Another object of the present invention is to provide an image forming apparatus in which an exposure unit and a development unit can be arranged with high accuracy.
[0013]
[Means for Solving the Problems]
According to the present invention, an image carrier on which a toner image is formed, an exposure unit for exposing the image carrier to form an electrostatic latent image on the image carrier, and an electrostatic unit on the image carrier An image forming apparatus comprising: a developing unit that develops a latent image with toner to form the toner image; and a toner cartridge that replenishes the developing unit with the toner, wherein the exposure unit, the developing unit, and the toner cartridge are mounted. A storage space in which the toner cartridge is stored, the exposure unit is disposed above the toner cartridge, and the toner body is disposed adjacent to the storage space. An image forming apparatus is provided in which the developing unit is positioned beside a cartridge.
[0014]
As described above, the apparatus main body in which the exposure unit (LSU), the development unit, and the toner cartridge are mounted is provided, and the storage space in which the toner cartridge is stored is defined in the apparatus main body, and the exposure unit is provided above the toner cartridge. And the developing unit is positioned beside the toner cartridge adjacent to the storage space, so that even if the capacity of the toner cartridge is increased, the exposure unit and the developing unit are not affected, and the image forming apparatus is not affected. The height of itself does not increase.
[0015]
For example, the exposure unit, the development unit, and a mounting member to which the toner cartridge is mounted are defined in the apparatus main body, and the development unit is mounted on the apparatus main body adjacent to the toner cartridge. May be formed as a mounting member for the developing unit.
[0016]
As described above, if the mounting member on which the exposure unit, the development unit, and the toner cartridge are mounted is defined in the apparatus main body, the exposure unit, the development unit, and the toner cartridge can be easily positioned. As a result, the exposure unit and the developing unit can be accurately arranged. If a rail member for mounting the developing unit to the apparatus main body is formed adjacent to the toner cartridge as a mounting member for the developing unit, the developing unit can be mounted very simply and accurately.
[0017]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the components described in this embodiment are not intended to limit the scope of the present invention thereto, unless otherwise specified. It is only an example.
[0018]
FIG. 1 is a perspective view showing a process unit body used in an image forming apparatus according to the present invention. In the illustrated example, a resin unit housing (hereinafter referred to as a main body base) 11 has a toner cartridge 12 and an exposure unit. A certain laser scanner unit (LSU) 13, a developing unit 14, and a drum unit 15 are mounted. The main body base 11 has a lower base 11a and an upper base 11b, and the lower base 11a and the upper base 11b are arranged at a predetermined interval. That is, a space (hereinafter referred to as a storage space) is defined by the lower base 11a and the upper base 11b.
[0019]
The lower base 11a is provided with a mounting base 21 on which the toner cartridge 12 is mounted (loaded). When the toner cartridge 12 is pushed along the mounting base 21 from the near side in the figure, the toner The cartridge 12 is mounted on the mounting base 21, and the toner cartridge 12 is stored in the storage space.
[0020]
An LSU 13 is arranged above the toner cartridge 12. An LSU attachment portion 22 is defined on the upper base 11b, and the LSU 13 is attached to the LSU attachment portion 22 by an LSU attachment base 13a. Is tilted.
[0021]
The developing unit 14 is housed in a part (front part) of the above-mentioned housing space, and the drum unit 15 is opposed to a developing roller (not shown in FIG. 11b, and the drum unit 15 faces the LSU 13 at this time. That is, the drum unit 15 is positioned at a position where the laser light from the LSU 13 is irradiated.
[0022]
2, the drum unit 15 includes an image carrier (photosensitive drum) 15a, a charger 15b, and a cleaning unit 15c. As described with reference to FIG. 1, the drum unit 15 and the developing unit 14 are provided. Is mounted on the main body base 11, the developing roller 14a faces the surface of the photosensitive drum 15a at a predetermined gap. Then, the laser beam from the LSU 13 irradiates the surface of the photosensitive drum 15a downstream of the charger 15b and upstream of the developing roller 14a in the rotation direction of the photosensitive drum 15a.
[0023]
The developing unit 14 is provided with a plurality of spiral screw bodies 14b and a toner supply roller 14c. The spiral screw body 14b and the toner supply roller 14c are housed in a developing unit housing 14d and supplied from the toner cartridge 12. The toner supplied to the developing roller 14a is transported in the direction of the developing roller 14a.
[0024]
Referring also to FIG. 3, FIG. 3 is a view of the developing unit 14 as seen from the rear (toner cartridge side). In FIG. 3, the upper surface of the developing unit housing 14d at the rear (the right end in FIG. 2) is provided. And a toner supply port 14e. Then, toner is supplied from the toner cartridge 12 to the toner supply port 14e.
[0025]
On the other hand, as shown in FIG. 2, the front end (the left end in FIG. 2) of the toner cartridge 12 is positioned above the toner supply port 14e, and the cartridge side supply port 12a is opened downward at the front end. It is formed. Then, toner is supplied from the cartridge side supply port 12a to the toner supply port 14e.
[0026]
In the toner cartridge 12, a replenishment spiral 12b is arranged. While the toner in the toner cartridge 12 is transported forward, the replenishment spiral 12b causes the developing unit 14 to move from the cartridge side replenishment port 12a through the toner replenishment port 14e. Will be replenished. When toner is replenished from the toner cartridge 12 to the developing unit 14, the replenishment spiral 12b is constantly driven to rotate, and the shortage is supplied to the developing unit 14.
[0027]
Here, referring to FIGS. 4 and 5, FIG. 4 is a perspective view showing a state where the drum unit 15 is removed, and FIG. 5 is a sectional view thereof. A pair of rail members 31 extending in parallel with the mounting table 21 is laid on the front side of the mounting table 21 on which the toner cartridge 12 is mounted, and the developing unit 14 is mounted on the rail member 31. . That is, the developing unit 14 can be pulled out to the near side in FIG. 4 along the rail member 31.
[0028]
The main body base 11 is provided with a lever member (not shown) at a position corresponding to the developing unit 14, and the lever member is rotated to mount and remove the developing unit 14. In the illustrated image forming apparatus, for example, at the time of maintenance, the lever member is rotated and the developing unit 14 is pulled out to the front side and detached from the main body base 11. When mounted on the base 11, the lever member cannot be rotated.
[0029]
That is, after the toner cartridge 12 is pulled out, the lever member is rotated to pull out the developing unit 14 along the rail member 31. Similarly, the toner cartridge 12 cannot be mounted on the main body base 11 unless the developing unit 14 is mounted on the main body base 11.
[0030]
As described above, the main body base is made of resin, and the rail member 31 on which the developing unit 14 is installed, the mounting base 21 on which the toner cartridge 12 is mounted, and the LSU mounting part 22 on which the LSU 13 is disposed are previously set in the main body. Since the developing unit 14, the toner cartridge 12, and the LSU 13 are formed on the rail member 31, the mounting base 21, and the LSU mounting part 22, respectively, the mounting of the toner cartridge 12 is easy. In addition, the developing unit 14 and the LSU 13 can be installed with extremely high accuracy. Since the main body base 11 is made of resin, the molding is extremely easy and the cost is low.
[0031]
Further, the toner cartridge 12 is stored in a storage space defined by the lower base 12a and the upper base 12b, the LSU 13 is disposed above the toner cartridge 12, and the developing unit 14 is stored in the storage space. 12, the image forming apparatus itself does not increase in height even if a large-capacity toner cartridge is used, and a small-sized image forming apparatus having a large-capacity toner cartridge is provided. Can be provided.
[0032]
Here, an outline of the image forming process is as follows. When an image is formed on a recording sheet (for example, when copying), first, the surface of the photosensitive drum 15a is uniformly charged by the charger 15b. A laser beam from the LSU 13 output according to image data is irradiated on the photosensitive drum 15a at the exposure light irradiation position to expose the photosensitive drum 15a and form an electrostatic latent image on the photosensitive drum 15a. I do.
[0033]
Then, the electrostatic latent image on the photosensitive drum 15a is developed by the developing roller 14a to form a toner image. On the other hand, a recording sheet is transported from a paper feed cassette (not shown) to a nip portion (transfer nip portion) between the photosensitive drum 15a and a transfer roller (not shown), and the toner image on the photosensitive drum 15a is transferred. Transferred to recording paper. The recording sheet onto which the toner image has been transferred is conveyed to a fixing unit (not shown), where the transferred image is fixed on the recording sheet, and the recording sheet is discharged to a discharge tray (not shown). After the toner image is transferred onto the recording paper as described above, the toner remaining on the photosensitive drum 15a is removed by the cleaning unit 15c, and is discarded in a waste toner container or the like (not shown).
[0034]
【The invention's effect】
As described above, according to the present invention, an exposure unit (LSU), a development unit, and an apparatus main body in which a toner cartridge is mounted are provided, and the storage space in which the toner cartridge is stored is defined in the apparatus main body. The exposure unit is located above the toner cartridge, and the developing unit is positioned next to the toner cartridge adjacent to the storage space. Therefore, even if the capacity of the toner cartridge is increased, the exposure unit and the developing unit are affected. There is an effect that the height is not increased and the height of the image forming apparatus itself is not increased.
[0035]
In the present invention, the exposure unit, the developing unit, and the mounting member to which the toner cartridge is attached are defined in the apparatus main body, so that the exposure unit, the developing unit, and the toner cartridge can be easily positioned. As a result, there is an effect that the exposure unit and the development unit can be accurately arranged.
[0036]
Furthermore, in the present invention, the rail member for mounting the developing unit to the apparatus main body is formed as a mounting member for the developing unit adjacent to the toner cartridge, so that the developing unit can be mounted very simply and accurately. This has the effect.
[Brief description of the drawings]
FIG. 1 is a perspective view showing a state in which a toner cartridge, a laser scanner unit, a developing unit, and a drum unit are provided in an apparatus main body in an example of an image forming apparatus according to the present invention.
FIG. 2 is a cross-sectional view of the image forming apparatus shown in FIG.
FIG. 3 is a schematic view of the image forming apparatus shown in FIG. 1 as viewed from the back (toner cartridge side).
FIG. 4 is a perspective view showing a state where a drum unit is removed in the image forming apparatus shown in FIG. 1;
FIG. 5 is a sectional view of the image forming apparatus shown in FIG.
[Explanation of symbols]
11 Unit housing (main unit base)
12 Toner cartridge 13 Laser scanner unit (LSU)
14 Developing unit 15 Drum unit 31 Rail member

Claims (3)

An image carrier on which a toner image is formed, an exposure unit for exposing the image carrier to form an electrostatic latent image on the image carrier, and developing the electrostatic latent image on the image carrier with toner An image forming apparatus comprising: a developing unit that forms the toner image and a toner cartridge that replenishes the developing unit with the toner.
The exposure unit, the developing unit, and an apparatus body on which the toner cartridge is mounted,
A storage space in which the toner cartridge is stored is defined in the apparatus main body, and the exposure unit is arranged above the toner cartridge,
The image forming apparatus according to claim 1, wherein the developing unit is positioned beside the toner cartridge adjacent to the storage space. 2. The image forming apparatus according to claim 1, wherein an attachment member to which the exposure unit, the developing unit, and the toner cartridge are mounted is defined in the apparatus main body. 3. The image forming apparatus according to claim 2, wherein a rail member for mounting the developing unit to the apparatus main body is formed as a mounting member for the developing unit adjacent to the toner cartridge.

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