JPS60120377A - Copying machine - Google Patents

Abstract

PURPOSE:To attach and inspect a photosensitive drum easily in safety by dividing a lower and an upper machine frame and separating the development part of a developing device provided to the upper machine frame from an image formation surface. CONSTITUTION:A two split type copying machine 51 is separated into the upper machine frame 51a containing an image forming process member and the lower machine frame 51 about a conveyance surface for recording paper which extends from a manual paper feed port to a discharge port, and they are coupled with each other by a hinge shaft H so that the upper machine frame 51a is opened freely. The developing sleeve 59a of the developing device 59 form a proper interval with a photosensitive drum 55, and a latent image on the photosensitive drum 55 is developed with toner supplied from a toner cartridge 59b.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a two-part type copying machine improved by providing a developing section of a developing device so as to be retractable from an image forming surface.

[Prior art]

The internal functions and arrangement of a typical electrophotographic copying machine are as shown in FIG.

i- In the figure, a sheet of recording paper P is delivered one by one from a paper feed cassette 2 installed in a copying machine L, passes through a first paper feed roller 3, is reversed, and then reaches a second paper feed roller 4. The timing and conveyance speed are adjusted so as to coincide with the leading edge of the toner image formed on the photosensitive drum 5.

On the other hand, prior to this, the photoreceptor drum 5, which is uniformly charged on its circumferential surface by the charging electrode 6 and rotates in the direction of the arrow, is placed in front of the original document which moves horizontally in synchronization with the circumferential speed of the photoreceptor drum 5. The image is transferred to the exposure lamp 7 and the focusing light transmitter (trade name,
An electrostatic latent image is sequentially formed on the surface using the SELFOC lens 8.

As the latent image on the photosensitive drum 5 is rotated, it is transferred to the developing section of the developing device 9, that is, the developing sleeve 9.
a toner image is developed into a visible state.

The photoreceptor drum 5 further rotates to combine with the recording paper P described above, and after transferring the toner image on the photoreceptor drum 5 onto the recording paper P by the transfer pole 10, 9- the recording paper P is transferred. They are separated and separated at the separation electrode 11.

The separated recording paper P is fed to the fixing roller 13 via the conveyance roller 12, and after the toner image is melted and fixed, the paper discharge roller 14 sends the paper P from the discharge port 15 to the paper discharge tray ( (not shown).

After separating the recording paper P, the photoreceptor drum 5 further rotates in the direction of the arrow, and after the electric charge is removed by the removal electrode 16, the cleaning blade 17m of the cleaning device 17 cleans the photoreceptor drum 5. The adhering residual toner is scraped off, and the scraped off toner is stored in the cleaner box 18. On the other hand, the photoreceptor drum 5 is again subjected to charge by the charging electrode 6 in order to form an electrostatic latent image based on the next document.

Note that 19 is the recording paper insertion slot for manual feeding, and is 3a.
is the first feeding roller.

In an electrophotographic copying machine having such a function, the photoconductor drum 5, whose performance deteriorates due to use or whose surface is scratched, and the cleaning blade 17a, which tends to wear out and deteriorate its performance, are periodically replaced with new ones. Since it is necessary to maintain the developer cartridge and the developer cartridge 9b must be frequently replenished with toner, these members are designed to be removable. In particular, since the photoreceptor drum 5 is developed by the developer attached to the developing sleeve 9a, the two are arranged extremely close to each other, and especially when a -component developer is used, the proximity is large (, Photosensitive drum 5
Alternatively, when attaching and detaching the developing device 9, extreme care must be taken to avoid damaging the photoreceptor due to contact.

Therefore, in order to facilitate the handling of these members, before removing the photoreceptor drum 5, manually remove the developing device 9.
A device equipped with a device for retracting the developing device 9, or a device configured so that when the developing device 9 is pulled out, it is pulled out along a guide rail and away from the photosensitive drum 5, or a worm 7 of a copying machine.
, a number of proposals have been made, including one in which the developing device 9 is evacuated from the photosensitive drum 5 using a moving device for the developing device 9 used at one time, but all of these methods require expensive parts such as solenoids. In addition, it requires a large number of punches and other mechanical parts, resulting in a high-cost component structure, and since all of them are manually operated, there is a risk of forgetting them, and the workability is poor.

For convenient inspection, parts replacement, repair, and troubleshooting, such problems can be solved using a two-part system in which the upper machine frame 1a is connected to the lower machine frame 1b so that it can be opened and closed with the hinge H as the center of rotation, as shown in Figure 1. This is considered to be an unavoidable problem even in copying machines.

[Purpose of the invention]

In the present invention, the developing sleeve of the developing device is automatically retracted from the image forming surface of the photoreceptor drum and maintained in a separated position when the lower machine frame is opened, so there is no need to worry about forgetting an operation, and the mechanism is simple. - The purpose is to provide a simple two-part copying device.

[Structure of the invention]

The present invention provides a two-part copying apparatus in which an upper machine frame housing a photoreceptor drum, a developing device, etc. is opened and closed relative to a lower machine frame by shaft coupling, and the lower machine frame is opened. When the developing device is tilted, it rotates under its own weight, moves to a predetermined position, and stops. This is because the lower machine frame and the lower machine frame can be separated into a copying machine. This is achieved by a copying apparatus characterized in that the upper machine frame is divided so that the developing section of the developing device provided in the lower machine frame is separated from the image forming surface.

〔Example〕

2 and 3 show an embodiment of a two-part copying device equipped with a developing device according to the present invention. FIG. 2 shows a state in which the copying device is used with the upper machine frame closed. Figure 3 shows the upper machine frame being opened to inspect paper feed defects and other parts.
This shows a state in which an exchange, etc. is performed.

The two-part copying apparatus 51 shown in FIG. 2 has an upper machine frame 51a and a lower machine frame 51b that house image forming process members, with the boundary being the recording paper conveyance surface from the manual paper feed port to the paper discharge port.
It is divided into two parts and connected by a hinge shaft H, so that the upper machine frame 51m can be freely opened.

The upper machine frame 51m includes a photoreceptor drum 55 as an image forming process member, a charging electrode gap, an exposure lamp 57, a focusing source transmission body, a cleaning device a1 and a developing device 5.
On the other hand, the lower machine frame 51b houses a second sheet feeding row 28 as a sheet feeding and conveying member, each conveying roller group including the fixing roller 63, and each transfer/separation electrode ω, 61.
A paper feed cassette 52, a driving power source, etc. are accommodated therein.

Further, in the present invention, the developing casing 59c of the developing device 59 in the upper machine frame 51m is housed in a guide rail 71 which is fitted in a circumscribed manner thereto, and has a shaft M fixed to the upper machine frame 51& as a fulcrum. The developer casing 59c and the guide rail 71 are configured to be able to rotate together, but when the upper machine frame 51m is closed and the copying device 51 is in use as shown in FIG. The developer casing 59c and the guide rail 71
The guide rail 71 receives a clockwise rotational moment due to gravity about the axis M as a fulcrum, and is stopped by coming into contact with the end 72m of the panel 72 fixed in the upper machine frame 51a.

Note that in this state, the developing sleeve 5 of the developing device 59
9a is formed with an appropriate distance from the photoreceptor drum 55 so that the toner cartridge 9a can fulfill the function of developing the latent image on the photoreceptor drum group with the toner supplied from the toner cartridge 59b. As is well known, the above interval is -
In the case of development using a component developer, the distance is 1 m or less, and in the case of development using a two-component developer, the distance is a long distance.

Next, the upper machine frame 51a is opened clockwise, and when the angle of 45° is reached, a stay device (not shown) provided between the upper machine frame 51a and the lower machine frame 51b is used to open the -upper machine frame. 51& is opened in the open state and stopped in the state shown in FIG.

At this time, the developing casing 59o and the guide rail 71
The guide rail 71 rotates under the counterclockwise rotational moment due to gravity about the axis M as a fulcrum, and the guide rail 71 is separated from the end 72a and its top 71a abuts against the inner wall of the panel 72 and is stopped.

In this state, the developing sleeve 59 of the developing device 59
It is also possible to set m to be thicker than the outer circumferential surface between the photoreceptor drums (separated from each other) and to make the distance sufficient so that there is no problem in replacing and attaching/detaching the photoreceptor drum group.

Therefore, when attaching and detaching the photoreceptor drum assembly for replacement, there is no danger of bringing the outer peripheral surface into contact with the developing device 59 and causing scratches on the photoreceptor surface.
Since it can be attached and removed parallel to the outer peripheral surface of the photoreceptor drum group along the guide rail 71, inspection, cleaning, toner replenishment, etc. can be easily performed without damaging the outer peripheral surface of the photoreceptor drum group. Become. In this embodiment, the developing device is set from the side of the copying machine body through a guide plate, but the document table provided at the top of the copying machine is eliminated,
It is also possible to insert and set the developing device from the top.

In this case, the upper part of the bearing is opened, and the shaft provided in the developing device is set therein.

〔Effect of the invention〕

The present invention is capable of automatically transferring the developing position to the developing position or the retracted position as the copying machine is opened and closed by using gravity, and the photosensitive drum can be easily attached/detached and inspected. Since it is possible to provide a safe two-part copying device, there are effects such as preventing damage to the surface of the photoreceptor in the developing section (also preventing scattering of developer, etc.).

[Brief explanation of the drawing]

FIG. 1 is a general internal configuration diagram of a copying machine. Figures 2 and 3 are internal configuration diagrams of a two-part copying machine according to the present invention.
Indicates the mode. 51... Copying device 51m... Upper machine frame 51b...
・Lower machine frame...Photoconductor drum group...Developing device
59m...Developing sleeve 59b...Toner cartridge, cartridge 59a...Developing casing 71...Guide rail 71 Tortoise...Top 72...
Panel 72m...End H/$11'M/@ Agent Yoshimi Kuwahara 10-

Claims (2)

[Claims] (1) In a copying device that can be divided into a lower machine frame and a lower machine frame, by dividing the lower machine frame and the upper machine frame, the developing section of the developing device installed in the lower machine frame is separated from the image forming surface. A copying device characterized by: (2) The copying apparatus according to claim 1, wherein the above-mentioned separation is performed by the weight of the developing device.