JPH0476109B2 - - Google Patents

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention provides a process unit in which an image bearing member, a developing means, and a cleaning means are contained in a cartridge, and the process unit can be removably loaded into the main body of a copying machine. The present invention relates to a copying machine that uses the following methods.

(Prior Art) Copying machines, such as electrophotographic copying machines, have become quite popular, and procedures such as replacing the photosensitive drum as an image bearing member, replenishing developer toner, and cleaning the cleaning part itself that cleans the photosensitive member are difficult. Although it is necessary to perform this on a regular basis, it is relatively difficult for users to do this, and it is common for users to rely on service personnel with special skills.

Therefore, recently, it has been proposed that the above photosensitive drum, developing section, and cleaning section are housed in a cartridge to form a process unit, and the process unit can be removably loaded into the main body of the copying machine. For example, JP-A-57-
See Publication No. 200051 or Japanese Patent Application Laid-open No. 57-200052.

According to this, by making it easy to handle the attachment and detachment, the user can easily replace the unit, and there is no need to rely on a service person.

By the way, if such a mechanism for replacing units is adopted, by using different colors of developer, it will be possible to make copies in a color that corresponds to the color of the original image, which is extremely convenient. ,
In this case, it is necessary to prepare a unit filled with developer of each color for each color.

Furthermore, if the fatigue of the photoreceptor reaches its limit and it becomes unusable, the unit itself must be replaced even though other parts can still be used normally, resulting in an economic loss.

In other words, in the conventional process unit, the photosensitive drum, the developing section, and the cleaning section are constructed as an inseparable unit and housed in a cartridge, so each part cannot be replaced.
This caused various inconveniences.

(Object of the invention) The present invention has been made in view of the above points, and
The purpose is to provide a copying machine in which each part is assembled to form a unit that can be detachably loaded into the main body of the copying machine, and in which each part of the unit can be separated and replaced. It is.

(Structure of the Invention) For this purpose, the present invention provides a process unit in which an image carrier, a developing device that forms an image according to information on the image carrier, and a cleaning device that cleans the image carrier are housed in a cartridge. , a copying machine in which the process unit can be removably loaded into a copying machine main body, in which the cartridge is housed in a first cartridge case containing the image carrier; a second cartridge case containing the developing device; It is formed from a third cartridge case containing the cleaning device, the second cartridge case and the third cartridge case.
The upper part of the cartridge case is screwed to the upper part of the first cartridge case, and the engaging protrusion protruding downwardly at the lower parts of the second cartridge case and the third cartridge case is connected to the upper part of the first cartridge case. The second cartridge case and the third cartridge case are each independent of the first cartridge case from a side surface thereof. It can now be attached and detached.

(Example) Examples of the present invention will be described below. 1st
The figure is a diagram schematically showing the entire copying machine. A document 3 placed on a platen glass 2 that uses a document table moving system that moves back and forth in the direction of arrow A with respect to the copying machine main body 1 is placed on a platen cover 4 with the image to be copied facing downward. When a button (not shown) is operated in this state, the platen glass 2 moves together with the original 3 and the platen cover 4, and the lower surface of the original 3 is exposed to the exposure light source 5.
The image of the lower surface of the document 3 is guided to a photosensitive drum 7 as an image carrier by a focusing light transmitter (trade name: Cellhok Lens) 6.

This photosensitive drum 7 is constructed by providing a photoconductive layer made of selenium or the like on the outer peripheral surface of a grounded metal cylinder.
It rotates in the direction of arrow B in conjunction with exposure scanning by relative movement of the platen glass 2 with respect to the exposure light source 5.

Further, this photosensitive drum 7 has a focusing light transmitting body 6.
Before the arrival of the image from the photoconductive layer, the portion of the photoconductive layer is, for example, uniformly charged by the charging electrode 8 to which a DC high voltage of, for example, 5 Kv is applied. As the original 3 is exposed and scanned, when a light image corresponding to the image of the original 3 is irradiated onto the photosensitive drum 7, the conductivity of the part receiving the light increases, and the conductivity of that part increases. The electrical charge escapes to the grounded metal cylinder of the photosensitive drum base, thereby causing the document 3 to be deposited on the surface of the photoconductive layer.
An electrostatic latent image corresponding to the image is formed.

When the photosensitive drum 7 further rotates in the direction of arrow B,
Negatively charged toner from the developing device 9 is attracted to the positively charged electrostatic latent image by electrostatic force. As a result, the toner is attracted to the portion where the positive charge remains, and a toner image corresponding to the electrostatic latent image is formed on the surface of the photosensitive drum 7.

The feed roller 1 is inserted from the paper feeding manual feed section 10.
The transfer paper sent in step 1 is sent out by a timing roller 12 at a timing such that the leading edge of the toner image and the transfer paper match in order to match the toner image on the photosensitive drum 7, and A direct current high voltage is applied to the transfer paper at the transfer section, and the toner image on the surface of the photosensitive drum 7 is transferred by the transfer pole 13 .

Thereafter, the transfer paper on which the toner image has been transferred is separated from the photosensitive drum 7 by, for example, a separation pole 14 to which AC high voltage is applied, and the separated transfer paper is guided with the toner image on its upper surface. Part 15
The toner image is fixed in a fixing section 16 having a heated fixing roller, and then delivered to a tray 18 by a paper discharge roller 17.

The photosensitive drum 7 is then neutralized by a removing electrode 19, and then its surface is cleaned by a cleaner (cleaning portion) 20, and then subjected to the next copying process. Through the above-described cycle, the original is copied.

Now, in this embodiment, the above-mentioned photosensitive drum 7,
Charging electrode 8, developing device 9, removing electrode 19, cleaner 2
0 is contained in the cartridge 21 to constitute one process unit U.

This cartridge 21 includes a first cartridge case 211 that houses the photosensitive drum 7 and the charging electrode 8;
Second cartridge case 2 that houses the developing device 9
12, and a third cartridge case 213 that houses the cleaner 20 and the removal electrode 19.

The cartridge case 212 is provided with a guide protrusion 212a on the side surface that is guided by the guide rail 22 provided on the copying machine main body 1, and an engaging recess 211a formed in the lower part of the cartridge case 211 at the lower part. An engaging convex portion 212b that engages with is formed, and a mounting projection 212c that is screwed onto a mounting projection 211b formed on the upper part of the cartridge case 211 is formed on the upper part.

On the other hand, the cartridge case 213 is provided with a guide protrusion 213a on the side surface that is guided by the guide rail 23 provided on the copying machine main body 1, and an engagement recess 211c formed in the lower part of the cartridge case 211 at the lower part. An engaging convex portion 213b that engages with is formed, and a mounting projection 213c that is screwed to a mounting projection 211d formed on the upper part of the cartridge case 211 is formed on the upper part.

A handle 24 is formed on the front face of the central cartridge case 211 for inserting or pulling out the entire cartridge 21 from the copying machine main body 1 (FIG. 2). 25 and 26 are mounting protrusions 2
11b and 212c, mounting protrusions 211d and 213c
If a thumbscrew is used for this screw, no tools are required to remove or tighten it. Reference numeral 211e designates an exposure slit formed on the upper surface of the central cartridge case 211.

The cartridge 21 can be assembled by combining the cartridge cases 211 to 213 as shown in FIGS. 1 and 2.
As shown in the figure, it is integrated and can be pulled out or pushed in from the copying machine main body 1 by grasping the handle 24.

Furthermore, when the screws 25 and 26 are loosened and removed, the cartridge cases 212 and 213 on both sides are opened laterally with respect to the central cartridge case 211, so that the engagement convex portion 2 is opened from the lower engagement recess 211a.
12b and the engagement protrusion 213b from the engagement recess 211c, each cartridge case 211, 212, 213 is divided and separated.

Therefore, it is easy to assemble the cartridge 21 containing each part, and therefore the entire process unit U is easy to assemble, and the developing device 9
Since the cartridge case 212 that contains the cartridge case 212 can be replaced independently, when copying in different colors or in multiple colors, it is only necessary to prepare the developing device 9 for each color. There is no need to prepare the entire cartridge 21 for each color. Furthermore, when the photosensitive drum 7 becomes fatigued or the photoconductive layer on its surface is damaged, only the cartridge portion 211 containing the photosensitive drum 7 or the photosensitive drum 7 can be replaced. Furthermore, it becomes easy to replace only the blade of the cleaner 20 or to clean the discharged toner inside the cleaner 20.

(Effects of the Invention) As described above, according to the present invention, it is possible to simplify the assembly work of each of the first to third cartridge cases, to easily perform separate replacement and cleaning of each case, and to easily change the copy color. realizable.

In addition, the second and third cartridge cases are
It is assembled by fitting and screwing into the cartridge case from the side, that is, pressing it from the side, so that the developing sleeve of the developing device contained in the second cartridge is attached to the image carrier contained in the first cartridge. The pressing, pressing of the blade of the cleaning device contained in the third cartridge against the image carrier, etc. are automatically performed.

[Brief explanation of the drawing]

FIG. 1 is a schematic explanatory diagram showing the entire copying machine equipped with a process unit according to an embodiment of the present invention, and FIG.
The figure is a perspective view of a cartridge constituting the same process unit, and FIG. 3 is an enlarged sectional view of the lower engaging portion of the cartridge. 7... Photosensitive drum, 8... Charging electrode, 9... Developing device, 19... Eliminating electrode, 20... Cleaner, 21
... Cartridge, 211-213 ... Cartridge case, 22, 23 ... Guide rail, 24
...Handle, 25, 26...Screw, U...Process unit.

Claims (1)

[Scope of Claims] 1. An image bearing member, a developing device for forming an image according to information on the image bearing member, and a cleaning device for cleaning the image bearing member are housed in a cartridge to form a process unit, and the process unit is In a copying machine that can be removably loaded into a copying machine main body, the cartridge includes a first cartridge case containing the image carrier, a second cartridge case containing the developing device, and a second cartridge case containing the cleaning device. the upper parts of the second cartridge case and the third cartridge case are screwed to the upper part of the first cartridge case; An engaging protrusion projecting downwardly at the lower part of the third cartridge case is engaged with an engaging recess facing upwardly at the lower part of the first cartridge case, and the second cartridge case and the third cartridge case are connected to each other. A copying machine characterized in that three cartridge cases are each independently attached to and detached from the first cartridge case from the side thereof.