JPH0219857A - Process cartridge and image forming device - Google Patents

Abstract

PURPOSE:To reduce the part number and the assembly manday of a device main body by composing a part of a paper feeding path with both a housing and a protecting cover or either of the two. CONSTITUTION:A process cartridge 1 is freely attached to and removed from the device main body 21, and a photosensitive drum 3, a cleaning unit 4, an electrostatically charging roller 5 and a developing unit 6 are included in the housing 2 as one unit. The protecting cover 7 which protects the photosensitive drum 3 and is freely opened and closed is installed on a part of the housing 2. Both housing 2 and the protecting cover 7 or either of the two is permitted as a part 10a of the paper feeding path. Thus, the part number and the assembly manday of the device main body 21 are reduced without increasing the part number and the assembly number of the process cartridge 1.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an image forming apparatus such as a copying machine, a computer, a facsimile machine, a word processor, etc., and a process cartridge that is detachable from the image forming apparatus.

(Prior Art) A process cartridge is provided with a protective cover for the purpose of protecting an image carrier such as a photoreceptor tram built into the process cartridge when the process cartridge is removed from the main body of an image forming apparatus and stored. A drum shutter (drum shutter) is provided, and the protective cover is opened when the process cartridge is loaded into the main body of the image forming apparatus.

(Problem to be solved by the invention) Therefore, when the process cartridge is loaded into the main body of the image forming apparatus, the protective cover does not perform any function and only occupies space. This results in a narrowing of the degree of freedom in design.

Furthermore, the housing of the process cartridge only contains consumable parts and developer, and does not serve any other function.
If a part of this housing is configured as a paper conveyance guide attached around the image carrier on the apparatus main body side, the number of parts and assembly steps of the process cartridge itself can be reduced without increasing the number of parts and the number of assembly steps. It is expected that the number of man-hours can be reduced.

The present invention has been made based on the above circumstances, and aims to reduce the number of parts and assembly man-hours of the device main body, and increase design freedom by configuring the protective cover and housing as part of the paper conveyance path. An object of the present invention is to provide a process cartridge that can contribute to the enlargement of images, and an image forming apparatus equipped with the process cartridge.

(Means for Solving the Problems) In order to achieve the above object, the present invention is capable of being detachably attached to the main body of an image forming apparatus, and housing an image carrier and other process equipment in one housing. In the process cartridge, the process cartridge has a protective cover that can be opened and closed to protect the image carrier in a part of the housing, and the housing and/or the protective cover form a part of the paper conveyance path. It is characterized by

Further, the present invention is characterized in that an image forming apparatus is configured including the above process cartridge.

(Function) Since the paper conveyance guide, which was conventionally provided on the main body side of the image forming apparatus, is formed by a part of the component parts of the process cartridge, the number of parts and the number of assembly steps on the process cartridge side are increased. It is possible to reduce the number of parts and the number of assembly steps on the device main body side, and to increase the degree of freedom in designing the device main body, without causing any problems.

(Example) Embodiments of the present invention will be described below based on the accompanying drawings.

FIG. 1 is a longitudinal cross-sectional view of an image forming apparatus according to the present invention, FIG. 2 is a vertical cross-sectional view of a process cartridge according to the present invention, and FIG.
The figure is a plan view of the same process cartridge.

A process cartridge L configured as a unit as shown in FIG. 2 is loaded into the main body 21 of the image forming apparatus 20 shown in FIG.
is configured to be detachable from the device main body 21.

The process cartridge 1 includes a photoconductor tram 3, a cleaning device 4, a charging roller 5,
It accommodates the developing device 6 and is configured as a unit. A drum shutter 7 that can be opened and closed is attached to a part of the housing 2. As shown in FIG. 2, when the process cartridge 1 is removed from the apparatus main body 21 and stored, the drum shutter 7 is closed. The drum shutter 7 prevents the photoreceptor tram 3 from being damaged or deteriorating due to exposure to external light.

By the way, the photoconductor tram 3 is to be rotationally driven in the direction of the arrow shown in the figure by a driving means (not shown), and the cleaning blade 8 of the cleaning device 4 and the charging roller 5 are in contact with the outer periphery of the photoconductor tram 3. Further, a developing sleeve 9 of the developing device 6 is disposed near the photosensitive drum 3 with an appropriate distance therebetween. Note that the developing device 6 is a developing container 10 that constitutes a part of the housing 2.
The toner t is stored inside the toner t, and this toner t is stirred and conveyed by the stirring means 11.

The process cartridge L is inserted into the apparatus main body 21 by inserting it from the front side in FIG. 1 to the back side in the direction perpendicular to the paper.
The drum shutter 7 is opened in conjunction with the loading operation, and the opened tram shutter 7 and a portion (guide portion) 10a of the developer container 10 are connected as shown in FIG. A paper conveyance guide is configured. still,
As shown in FIG. 3, rectangular openings 12 and 13 are formed in the tram shutter 7 and developer container 10 (guide portion 10a) of the process cartridge L, respectively.
As shown in the figure, the process cartridge l is attached to the main body 21 of the apparatus.
These openings 12.13 when loaded in
The openings are 2 facing each other. Is it desirable that the opening 12 formed in the drum shutter 7 be provided in a position where it is difficult for outside light to reach the photoreceptor 3 when the drum shutter 7 is closed? This is determined by the distance from the to the transfer section, etc., so this must be taken into consideration when designing.If outside light inevitably reaches the photosensitive drum 3, a seal should be placed on the opening 12. The sticker may be pasted and then removed when the process cartridge l is loaded into the apparatus main body 21.

On the other hand, above the process cartridge l in the apparatus main body 21, a transfer roller 22. Fixing rollers 23 and 24, a paper ejection roller 25, and a paper conveyance guide 26 are arranged, and the process cartridge l
A folding mirror 27 is arranged below. or,
Opening 12.13 formed in the process cartridge l
An optical sensor 28 and a light 29 are disposed near the , sandwiching them from above and below. Furthermore, the device main body 2
1, a paper ejection cassette 30 and a paper feed cassette 31 are inserted and set in the lower two stages of -L from the right side in FIG. A paper feed roller 32 and a laser scanner 33 are located above and below the portion facing the paper feed cassette 31 inside.
are arranged respectively.

Next, the main image forming device! The image operation at 120 will be explained.

The transfer material P loaded in the paper feed cassette 31 is sent out by a rotating paper feed roller 32. The transferred transfer material P passes through a paper conveyance guide constituted by the drum shutter 7 of the process cartridge L and a portion 10a of the developer container 1O, but at this time, the transfer material P is emitted from the light 29. In order to block the light, the optical sensor 28 detects this, and thereby the position of the transfer material P is detected, and a CPU (not shown) starts writing to the exposure area, and the writing position on the transfer material P is adjusted. . Note that a contact type sensor may be used instead of the optical sensor 28.

On the other hand, the photosensitive drum 3 of the process cartridge L is
It is rotated in the direction of the arrow in the figure, and after its outer circumferential surface is uniformly charged by the charging roller 5, this outer circumferential surface is irradiated with laser light emitted from a laser scanner 33, and the outer circumferential surface is static. A latent image is formed. This electrostatic latent image is developed as a toner image by the developing device 6, and this toner image is transferred to the transfer material P by the transfer roller 22.
The image is transferred onto the transfer material P and then fixed on the transfer material P by fixing rollers 23 and 24. In this way, the transfer material P on which the toner image has been fixed is conveyed along the paper conveyance guide 26 by the rotating paper discharge roller 25, and finally discharged onto the paper discharge cassette 30.

As described above, in this embodiment, conventionally the device main body 2
This is because the paper conveyance guide provided on the first side is composed of the drum shutter 7 and a part 10a of the developer container 10 on the process cartridge L side.

It is possible to reduce the number of parts and assembly man-hours of the apparatus body 21 without increasing the number of parts and assembly man-hours of the process cartridge 1, and it is possible to increase the degree of freedom in designing the apparatus body 21.

Next, a modified embodiment of the present invention will be described based on FIGS. 4 and 5. 4 is a longitudinal cross-sectional view of an image forming apparatus according to a modified embodiment, and FIG. 5 is a longitudinal cross-sectional view of a process cartridge. In these figures, the same elements shown in the first embodiment are the same. The same symbols are attached.

In this embodiment, the drum shutter 7 provided in the process cartridge 1 is divided into two parts, a first shutter piece 7a and a second shutter piece 7b.
a, 7b are respectively supported by two support members 34.35 and 36.37 having rotation centers a, b, c, and d on the housing 2 side, and these shutter pieces 7a, 7
Each end of b is connected to the support member 34°35 at points e, f, g, and h.
．． 36. It is rotatably connected to the tip of 37. still,
In FIG. 4, 38 is a paper conveyance guide, and 39.40 is a registration roller.

When the process cartridge l is removed from the apparatus main body 21 and stored as shown in FIG. 5, both shutter pieces 7a and 7b are in the solid line position in the figure, and the drum shutter 7 is closed. photoreceptor drum 3 (
(see FIG. 4) is protected by the drum shutter 7.

When the process cartridge l is loaded into the apparatus main body 21 as shown in FIG. 4, the drum shutter 7 opens in conjunction with this loading operation, and both shutter pieces 7a and 7b are opened.
is moved to the position shown in FIG. 4 (or shown by the broken line in FIG. 5) between the fixing roller 23, 24 and the transfer roller 22,
It functions as a paper conveyance guide between the transfer roller 22 and the registration rollers 39 and 40.

In this way, also in this embodiment, since the shutter pieces 7a and 7b of the drum shutter 7 provided on the process cartridge L side function as paper conveyance guides, the same effect as that obtained in the first embodiment can be obtained. It will be done.

By the way, the positions of the rotation centers a, b, c, d of the support members 34, 35, 36° 37 on the housing 2 side are as follows:
Straight line sentence 11 shown by the chain line in Figure 5! L21 Sentence Yu 9th sentence, you can choose any point above. In addition, direct sentence 1. Interchange 29
Sentence 31 is the perpendicular bisector of the line segment that connects each connection point e, f, g, 1 before movement and each connection point e-, f', g', h- after movement. It is.

(Effects of the Invention) As is clear from the above description, according to the present invention, the image forming apparatus is configured such that it can be attached to and detached from the main body of the image forming apparatus, and an image carrier and other process equipment are housed in one housing. , in a process cartridge having a protective cover that can be opened and closed to protect the image carrier as a part of the housing, since the housing and/or the protective cover constitute a part of the paper conveyance path; It is possible to reduce the number of parts and assembly man-hours on the image forming apparatus main body side, and to increase the degree of freedom in designing the apparatus main body, without increasing the number of parts and assembly man-hours on the image forming apparatus main body side.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional view of an image forming apparatus according to the present invention, FIG. 2 is a vertical cross-sectional view of a process cartridge according to the present invention, and FIG.
4 is a longitudinal sectional view of an image forming apparatus according to a modified embodiment of the present invention, and FIG. 5 is a longitudinal sectional view of the process cartridge according to the modified embodiment. l...process cartridge, 2...housing,
3... Photosensitive drum (image carrier), 7... Drum shutter (protective cover), 12.13... Opening, 2
0... Image forming device, 21... Image forming device main body. Patent applicant Canon Co., Ltd.

Claims (3)

[Claims] (1) It is detachable from the main body of the image forming apparatus, and
In the process cartridge, the process cartridge is configured by housing an image carrier and other process equipment in two housings, and has a protective cover that can be opened and closed to protect the image carrier in a part of the housing, wherein both the housing and the protective cover Alternatively, a process cartridge characterized in that either one constitutes a part of a paper conveyance path. (2) The process cartridge according to claim 1, wherein an opening for a paper sensor is formed in either or both of the housing and the protective cover. (3) An image forming apparatus comprising the process cartridge according to claim 1 or 2 above.