JPH10207171A - Color image forming equipment - Google Patents

Abstract

(57) Abstract: An object of the present invention is to provide a color image forming apparatus which can be reduced in size even when a so-called tandem system is adopted, and which can easily perform jam processing on a recording medium conveyance path. . A plurality of process units having the same configuration are provided, and a plurality of process units are arranged in parallel so that a recording medium can be conveyed toward a transfer unit of each process unit. In a color image forming apparatus configured to form a color image by combining,
Each exposure unit 8 'of each process unit is assembled at the most upstream side and / or the most downstream side in the recording medium transport direction so that the surface of each photoconductor can be optically scanned.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tandem type collar.
An image forming apparatus uses a plurality of process units to provide a more compact arrangement.

[0002]

2. Description of the Related Art In a conventional color image forming apparatus, a so-called tandem system in which process units for forming an image are arranged in the direction in which a recording medium is conveyed is conventionally known. FIG. 4 shows such a method.
Inside the color image apparatus 400, the fed recording medium is fed from a paper feeding unit 401 that stores the recording medium, passes through a conveyance path 405, passes through a plurality of process units, and is sent to a fixing device 404.

In such a configuration, a plurality of process units are composed of a plurality of exposure units, ie, an exposure unit 403A.
To 403D, the exposure unit 403A
When ４０３403D is arranged, it is generally arranged above the developing device of each process unit.

However, in such a configuration, in order to remove a jam during printing on a recording medium, the side door of the image forming apparatus is opened, and the process unit or a part of the developing unit is pulled out to the side. Thereafter, the paper was removed. Also, toner cartridges or toner hoppers for replenishing toner are provided with exposure units 403A to 403D.
Has to be placed above or beside the exposure units 403A to 403D.

[0005]

However, the conventional technology is advantageous in reducing the cost and the number of manufacturing and assembling steps by sharing the components of the process unit, and can secure the high-speed transportability unique to the tandem system. However, since the exposure unit is disposed above the process unit, the entire apparatus becomes large, and the problem that the jam processing becomes complicated remains.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems. In a color image forming apparatus, even when a so-called tandem system is adopted, the color image forming apparatus can be reduced in size and can easily perform jam processing on a recording medium conveyance path. It is an object to provide an image forming apparatus.

[0007]

In order to solve the above problems, the present invention forms a latent image by scanning a surface of a photoreceptor with a laser, develops the latent image by a developing unit, and develops the latent image by a developing unit. A plurality of process units having the same configuration for forming an image by transferring the imaged toner image to a recording medium by a transfer unit are provided, and the process units are arranged in parallel to transfer the recording medium to the transfer unit of each of the process units. In a color image forming apparatus configured to be capable of being conveyed toward the recording medium and configured to form a color image by superimposing images transferred to the recording medium, each exposure unit of each of the process units may be disposed in the recording medium conveyance direction. They are assembled at the most upstream side and / or the most downstream side so as to be capable of optical scanning on the surface of each photoconductor.

[0010] According to this configuration, the jam processing, toner exchange, and the like can be performed from the upper space without disposing the optical unit serving as the exposure unit near the process unit, and the upper direction can be reduced in thickness and the size can be reduced. .

In addition, the respective exposure means are vertically arranged side by side, and a folding mirror for determining a light scanning position on the surface of the photoconductor by the respective exposure means is arranged near the upper part of each of the process units. The folding position and the number of folding mirrors may be appropriately set so that the distance from the means to the photosensitive member scanning position is the same.
As a result, a plurality of common process units having the same configuration are juxtaposed, and the exposure unit having the same configuration is used, so that exposure adjustment is easy and the number of manufacturing and assembling steps is reduced.

Further, the lowermost stage of the vertically arranged exposure means can be optically scanned by a process unit arranged at the longest distance from the exposure means, and then sequentially goes from the lowest stage to the upper exposure means. Accordingly, the process unit at a position approaching the exposure unit may be configured to be optically scannable. As a result, when the lowermost exposure unit optically scans the longest process unit, the optical path is shorter than when the uppermost exposure unit optically scans the longest process unit, and the size of the device is reduced. Is done.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a view showing the internal configuration of a process unit 1 of the present invention. Reference numeral 2 denotes a photoconductor for forming a toner image. Reference numeral 3 denotes a charger for charging the surface of the photoconductor 2. Reference numeral 4 denotes an optical path of a reflection mirror unit 8. A developing unit (developing means) for attaching toner to the latent image formed from the toner to form a visible image; 5, a transfer roller (transfer means) for transferring the visualized toner image to a recording medium; A cleaning unit for cleaning the transfer toner, 7 is a toner container containing toner, 8 is a lens unit configured so that a laser beam 80 is turned back and scans the photoconductor 2, and a laser beam from an exposure unit 8 'described later is used. Is output. In addition, in order to facilitate exposure timing, etc.,
In each process unit 1, the process unit 1 has the same configuration, and the exposure unit has the same configuration.

Further, the process unit 1 is integrally formed with the reflection mirror unit 8, and is configured to be integrally detachable in the upward direction of the color image forming apparatus (specifically, not shown). As shown in the cross-sectional views of the exposure units A to D in FIG. 2, light from a laser (not shown) is scanned in the axial direction of the photoconductor 2 by a polygon mirror 8a, and light from the polygon mirror 8a is converted to fθ. A laser beam 80 is output after passing through a lens group 8b such as a lens.

FIGS. 3 to 5 show the arrangement of tandem type exposure units. As shown in the drawing, the process units are arranged side by side above the paper feed unit 9. The moving direction of the recording medium is supplied from the right side of the drawing and is conveyed to the left side. A fixing device 10 is disposed at the most downstream side in the transport direction of the recording medium, and the toner image transferred to the recording medium is permanently fixed.

A to D of the exposure units 8 'are arranged side by side in the vertical direction as shown in FIGS. 3 and 4, and FIG. 3 is arranged on the downstream side in the recording medium transport direction. Are collectively arranged on the upstream side. In FIG. 5, the first exposure units A and B are arranged on the upstream side in the recording medium conveyance direction, while the exposure units C to D are arranged on the downstream side.

With such a configuration, the process unit 1
The exposure units A to D do not exist in the upward direction, so that the jam processing or the like can be performed from the upward direction of the color image forming apparatus.

[0016]

According to the configuration of the present invention, each exposure means of the process unit is assembled at the most upstream side and / or the most downstream side in the recording medium transport direction so as to be capable of optically scanning the surface of each photosensitive member. Therefore, a space above each process unit can be provided, and not only the process unit but also a consumable such as a toner container can be removed for each process unit having a different color from above, so that maintenance such as jam processing can be improved.

Further, eliminating the need to install the exposure unit on each process unit can reduce the thickness of the apparatus.

[Brief description of the drawings]

FIG. 1 is a diagram showing an internal configuration of a process unit of the present invention.

FIG. 2 is a sectional view of an exposure unit.

FIG. 3 is a configuration diagram of an exposure unit of the present invention.

FIG. 4 is a configuration diagram of an exposure unit of the present invention.

FIG. 5 is a configuration diagram of an exposure unit of the present invention.

FIG. 6 is a conventional explanatory view.

[Explanation of symbols]

 1: Process unit 2: Photoreceptor 3: Charger (charging means) 4: Developing device (developing means) 5: Transfer roller (transfer means) 6: Cleaning device 7: Toner container 8: Reflection mirror unit 8 ': Exposure unit Group 8a: polygon mirror 8b: lens group 9: paper feed unit 10: fixing unit

Claims (3)

[Claims] A latent image is formed by scanning a laser on the surface of a photoreceptor, the latent image is developed by a developing unit, and a toner image visualized by the developing unit is transferred to a recording medium by a transfer unit. A plurality of process units having the same configuration for forming an image by using a plurality of the process units, the process units are arranged side by side, the recording medium is configured to be conveyable toward a transfer unit of each of the process units, and is transferred to the recording medium. In a color image forming apparatus configured to form a color image by superimposing images, each exposure unit of each of the process units is gathered at the most upstream side and / or the most downstream side in the recording medium conveyance direction, and A color image forming apparatus configured to be capable of optically scanning the surface of a photoreceptor. 2. The apparatus according to claim 1, wherein each of the exposing means is vertically arranged, and a folding mirror for determining a light scanning position on the surface of the photoconductor by each of the exposing means is arranged near an upper portion of each of the process units. 2. The color image forming apparatus according to claim 1, wherein the return position and the number of return mirrors are appropriately set so that the distance from the means to the photosensitive member scanning position is the same. 3. The apparatus according to claim 1, wherein a lowermost stage of the vertically arranged exposure means is optically scannable to a process unit arranged at a longest distance from the exposure means, and then sequentially to an uppermost exposure means. 3. A color image forming apparatus according to claim 2, wherein a process unit located closer to said exposure means is capable of optical scanning as it goes.