JPH0439666B2 - - Google Patents

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention provides a process unit in which at least an image bearing member and a developing means are housed 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-mentioned photosensitive drum, developing section, cleaning section, etc. are housed in a cartridge to form an integrated process unit, and the process unit can be removably loaded into the main body of the copying machine. has been done. For example, JP-A-57-200051, or JP-A-57-200052
See publication.

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 this mechanism for replacing units is adopted, by changing the color of the developer, it will be possible to copy in a color that corresponds to the color of the original image or in a color of one's choice, which is a huge improvement. Although this is convenient, in this case it is necessary to prepare a unit filled with developer for each color.

In other words, since the conventional process unit is constructed as a unit as a cartridge in which the whole, including the developing part, is inseparable and integrated,
Each part could not be replaced, causing inconvenience.

(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 integrally attached to and removed from the copying machine body, while the developing part within the unit can be separated and replaced. It is.

(Structure of the Invention) For this purpose, the present invention includes at least an image bearing member and a developing device for forming an image on the image bearing member contained in a cartridge to form a process unit, and the process unit is detachably attached to the main body of a copying machine. In a copying machine that can be loaded, the cartridge is provided with a two-part cartridge case as an outer casing that opens and closes using a pivot point, and a recess on the side surface of the developing device and a recess on the side surface of the developing device are provided inside one of the cartridge cases. A plate spring is provided to press both ends to elastically hold the developing device in a detachable manner, and by closing both the cartridge cases and locking them with a locking member, an exposure slit is formed at the abutting portion of the two cartridge cases. I made it so that it would be done.

(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 original 3 is transferred to a photosensitive drum 7 as an image carrier by a collecting beam light transmitting member (product name: Selhok Lens) 6.
guided by.

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 transfer paper fed by the feed roller 11 inserted from the paper feeding manual feed section 10 is fed 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. The transfer paper is sent out by the timing roller 12, and a direct current high voltage is applied 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 is depicted 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. Copying of the original is performed through the above-described cycle.

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.

As shown in FIG. 2, this cartridge 21 is constructed so as to be divided and opened at an exposure slit 211 on the upper surface. That is, this cartridge 21 has two cartridge cases 2.
12 and 213 as an outer casing, the lower portion of which is pivotally supported by a shaft 22. Further, in the upper part of one cartridge case 213, a lock pawl 23 is pivotally supported on a shaft 24 on the front and rear surfaces.
This lock claw 23 is connected to the other cartridge case 2.
Both cartridge cases 212
and 213 are configured to be locked in the closed state. 26 is a handle formed on the front side of the cartridge case 213. Furthermore, guide protrusions 212a and 213a are formed on the side surfaces of both cartridge cases 212 and 213, so that they are guided by guide rails 27 and 28 provided on the copying machine main body 1 side.

Therefore, with the cartridge 21 closed and the lock claw 23 locked, the process unit U can be loaded into the copying machine main body 1 by grasping the handle 26, or can be pulled out and taken out. It becomes possible.

The developing device 9 is loaded inside one cartridge case 212 of the cartridge 21, and its loading structure is constructed as shown in FIG. That is, inside the cartridge case 212, a resilient plate spring 29,
29 are provided so as to face each other, and a leaf spring 30 having elasticity downward from the top surface is also provided.

Therefore, if the toner storage portion, sleeve, etc. that constitute the developing device 9 are integrated, and the developing device 9 is fitted between the leaf springs 29 and 30,
The developing device 9 is held in that position by the elasticity of leaf springs 29 and 30. Incidentally, since the leaf spring 30 exerts its elasticity while being engaged with the recess 9a on the outer surface of the developing device 9, the developing device 9 is held in a locked state. Furthermore, the developing device 9 fitted and locked in this manner can be easily removed by applying a little force and pulling it out.

Therefore, the developing device 9 is connected to the process unit U.
Since the developing device 9 can be separated and replaced independently from the developing device 9, when making copies in different colors or in multiple colors, it is only necessary to prepare the developing device 9 for each color, and instead of using the unit U as in the past. There is no need to prepare the entire cartridges 21 for each color.

(Effects of the Invention) As described above, according to the present invention, even when copying in different colors, it can be achieved by replacing only the developing means, and there is no need to prepare as many process units as the number of colors as in the past. It has the characteristic of disappearing. Further, since the developing device attachment/detachment mechanism is a mechanism in which the developing device is pressed by a leaf spring, there is an advantage that the developing device can be easily attached/detached by the user.

[Brief explanation of drawings]

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 process unit, and FIG. 3 is a perspective view of the cartridge in an open state. 7...Photosensitive drum, 8...Charging electrode, 9...Developing device, 19...Removal electrode, 20...Cleaner, 21
...Cartridges that make up the process unit,
211... Exposure slit, 212, 213...
Cartridge case, 22... shaft, 23... lock claw, 24... shaft, 25... pin, 26... handle, 27, 28... guide rail, 29, 30...
...plate spring, U...process unit.

Claims (1)

[Scope of Claims] 1. At least an image carrier and a developing device for forming an image on the image carrier are housed in a cartridge to form a process unit, and the process unit can be detachably loaded into the main body of a copying machine. In the copying machine, the cartridge is provided with a two-part cartridge case as an outer casing that opens and closes with a pivot point as a fulcrum, and a recess on the side surface and both ends of the developing device are pressed inside one of the cartridge cases. A plate spring is provided to elastically hold the developing device in a detachable manner, and by closing both cartridge cases and locking them with a locking member, an exposure slit is formed at the abutting portion of the two cartridge cases. A copying machine characterized by: