JPH0361972A - Clamshell type electrophotographic image forming device - Google Patents

Abstract

PURPOSE:To surely and easily carry out the treatment operation of checking and cleaning by attaching and detaching a development cartridge in a direction parallel to a rotational supporting shaft according as a drum cartridge is attached and detached in the direction perpendicular to the rotational supporting shaft of a clamshell opening and closing part. CONSTITUTION:The device is separately provided with the photosensitive drum cartridge 500 including a cleaner 100, an electrifier 20, a pre-electrifying electrode 90, an toner recovering part 30, etc., and the development cartridge housing developing units 611A - 611D containing the developers of yellow, magenta, cyan and black and serving as a developing means. The development cartridge is attached and detached in the direction parallel to the rotational supporting shaft according as the drum cartridge 500 is attached and detached in the direction perpendicular to the rotational supporting shaft of the clamshell opening and closing part. Thus, the device is finely observed, and surely and easily cleaned and checked.

Description

Detailed Description of the Invention [Industrial Field of Application] The present invention provides a cartridge for the photoreceptor drum and developing device of an electrophotographic image forming apparatus, which are removably attached to each other, thereby facilitating cleaning and inspection inside the image forming apparatus. This invention relates to an improvement in which the cartridge can be replaced safely and reliably with a new one at the end of a specified number of uses.

[Conventional technology]

Conventionally, in electrophotographic image forming apparatuses, a photoreceptor drum and a developing device are included in one removable unit, or one unit including the photoreceptor drum and one unit including the developing device, respectively. Some were constructed into removable units. It was designed to enable easy and reliable internal inspection, parts replacement, and cleaning of the electrophotographic image forming apparatus. But it wasn't enough.

There is a limit to the number of times a photoreceptor can be used repeatedly for image formation, and it has become common to replace it with a new one at a usage limit of 10,000, 30,000, or 50,000 times. There is a limit to the number of times a product can be used, so it was often replaced with a new product.

[Problem to be solved by the invention]

The photoreceptor and the developing device have a durability limit that allows them to maintain good image quality, and this limit is generally determined by the number of times they are used for image formation. In addition to replacing the device with a new one so as not to exceed this durability limit, it is also necessary to inspect and clean the inside of the image forming device before the end of the durability period to ensure that the device continues to function normally. There is.

Moreover, it is desirable to be able to do it correctly in a simple procedure without requiring any skill. Therefore, the areas around the photoreceptor and the developing device were each housed in one cartridge to make it easier to attach and detach, and to make inspection and cleaning easier.

However, the developing roller (developing sleeve) of the developing device is in close contact with the surface of the photoreceptor drum, and both ends of the sleeve are often in contact with the surface of the photoreceptor drum.

Due to this situation, if the cartridge for the photosensitive drum and the cartridge for the developer are installed and removed separately in the same direction, the contact portions of the drum surface and both ends of the developing sleeve will rub against each other, causing the This may cause damage such as scratches on the drum surface. If this happens during a mid-way cleaning inspection, it becomes unclear what the cleaning inspection is for, and the resulting image finish is disturbed, causing a serious problem. One method is to house the photoreceptor drum and developer in one cartridge, which can prevent such disturbances caused by their mutual rubbing, but on the other hand, if they are kept in one piece, it is difficult to observe fine details. A problem arises in that cleaning inspections are difficult and incomplete due to the lack of access. An object of the present invention is to provide a clamshell type electrophotographic image forming apparatus that eliminates such problems.

[Means to solve the problem]

This purpose is to provide a clamshell electrophotographic image forming device with
In this case, a drum cartridge containing a photosensitive drum and a developing cartridge containing a developing device are provided separately, and the drum cartridge is attached and detached in a direction perpendicular to the pivot shaft of the clamshell opening/closing part. This is achieved by a clamshell type electrophotographic image forming apparatus characterized in that the developer cartridge is installed and removed in a direction parallel to the rotation support shaft.

〔Example〕

An embodiment of the present invention is shown in FIGS. 1 to 4.

1 and 2 are side sectional views showing the structure of the electrophotographic image forming apparatus of the present invention, and FIG. 1 is also a cross-sectional view taken along line xx' in FIG. It also represents.

In the drawings, reference numeral 10 denotes a drum-shaped image carrier, ie, a photosensitive drum, which is rotated clockwise in FIG. 2 and counterclockwise in FIG. 20 is a charging electrode that applies an electric charge to the photoreceptor on the circumferential surface of the photoreceptor drum 40, and 30 is a laser writing system unit that is an exposure optical system.

When a laser writing signal is input to the laser writing system unit 30, in the laser writing system unit 30, a laser beam generated by a semiconductor laser (not shown) is applied to a polygon mirror 3 rotated by a drive motor 31.
2, the optical path is bent by three mirrors 34A, 34B, and 34G through an fθ lens 33,
The light is projected onto the circumferential surface of the photoreceptor drum IO to which a charge has been previously applied by the charging electrode 20.

On the other hand, when scanning is started, the laser beam is detected by the index sensor, modulation of the laser beam by the first color signal is started, and the modulated laser beam scans the circumferential surface of the photoreceptor drum IO. Therefore, a latent image of the first color is formed on the circumferential surface of the photoreceptor drum 10 by main scanning by the laser beam and sub-scanning by the rotation of the photoreceptor drum IO. This latent image is developed by a developing means containing a developer of, for example, yellow as a first color, and a yellow toner image is formed on the circumferential surface of the photoreceptor drum 40. The obtained toner image, while being held on the circumferential surface of the photosensitive drum 10, passes under the cleaning means that is separated from the circumferential surface of the photosensitive drum IO, and enters the next copy cycle.

That is, the photosensitive drum 10 is charged again by the charging electrode 20, and then the second
A color signal of
Writing is performed on the peripheral surface using the second color signal to form a latent image. The latent image is developed by a developing means containing developer of a second color, for example magenta.

This magenta toner image is formed over the previously formed yellow toner image.

The toner image thus obtained, while being held on the circumferential surface of the photoconductor drum 10, passes under the cleaning means that is separated from the circumferential surface of the photoconductor drum IO, and enters the next copy cycle.

Similarly, writing is performed on the photosensitive drum 10 using the third color signal to form a latent image. This latent image is developed by a developing means containing a developer of a third color, for example cyan. This cyan i-toner image is formed superimposed on the yellow-magenta toner image described above.

As described above, a color toner image is formed on the photoreceptor drum 10 using the three color toners, but a high quality color image can be obtained by further overlapping a black toner image in the same manner.

Reference numerals 611A, 611B, 611C, and 611D are developing units that are developing means that contain yellow, magenta, cyan, and black developers, respectively, for performing the above-mentioned development.

As shown in the example of the developing device 611A, each developing device has a developing roller (developing sleeve) 612 that faces the circumferential surface of the photoreceptor drum 10 with a predetermined gap therebetween and has a magnetic pole fixed on the inside. It is equipped with a pair of stirring rollers 614 and 615 having conveying force in opposite directions, and the stirring roller 614
The developer is supplied to the circumferential surface of the rotating developing roller (developing sleeve) 612 after the toner and carrier components are made uniform by the mixing action of and 615.

A direct current or even alternating current bias is applied to the developing roller (developing sleeve) of each developing device that carries developer.
Non-contact reversal development is performed using a two-component developer.

Charging by the charging electrode 20 provided on the photosensitive drum 10 and its periphery, exposure by the laser writing system unit 30 for each color, and developing units 611A, 611B, 6
The development processing by 11C and 611D is performed four times for each color, so that color toner images are formed on the circumferential surface of the photoreceptor drum 10 by overlapping.

Reference numerals 61 and 62 are a first paper feed roller and a second paper feed roller, respectively, which are in a constantly rotating state, and 71 and 72 are paper feed guides having an arcuate shape and a linear shape, respectively.

The recording paper is carried out one by one from the paper feed cassette, and is sent along the paper feed guide 71 by the first paper feed roller 61 to the U.
After turning, that is, turning upside down, the paper contacts the rising portion of the paper feed shutter S that quickly cuts the conveyance path of the paper feed guide 72 and temporarily stops. In this case, the second paper feed roller 62 continues to rotate by sliding the stopped recording paper over its surface.

When the paper feed shutter S retracts downward in synchronization with the rotation of the photoreceptor drum IO carrying the toner image, the recording paper is synchronized with the circumferential speed of the photoreceptor drum 10 by the frictional force of the second paper feed roller 62. and is fed to the transfer section.

Reference numeral 80 denotes a rotatable transfer roller, which is charged with a voltage applied thereto, and has a transfer section that transfers the toner image to the recording paper side via the conveyor belt 80B at the point of contact with the circumferential surface of the photoreceptor drum 10. Configure. A conveyor belt 80B is stretched between the transfer roller 80 and a drive roller 280A rotating counterclockwise, and the recording paper is transferred while being conveyed by the conveyor belt I-80B. Note that 80C is a cleaning means for cleaning the surface of the conveyor belt 80B.

Reference numeral 90 denotes a front charging electrode located upstream of the cleaning device 100, which charges the electrode to a state where it is easy to remove the residual toner on the circumferential surface of the photosensitive drum 10 from which the toner image has been transferred to the recording paper.

100 is a cleaning device, 110 and 120 are a conductive bristle brush and a conductive collecting roller which are cleaning means of the cleaning device 1100, and 130 is a waste toner collecting section that stores toner collected by the cleaning means.

The photosensitive drum IO that has passed the front charging electrode 90 is brought into sliding contact with the conductive bristle brush 1 by a signal from the control section.
10, the residual toner adhering to the conductive brush 110 is adsorbed by the conductive collection roller 120, and then transferred to the waste toner collection section 13.
Sent to 0.

The waste toner collecting section 130 is provided with a waste toner sending rod 131 and a deformable toner collecting bag 132, and the residual toner, that is, waste toner sent by the collecting roller 120 is sent through the waste toner sending rod 131. Bag member 1
It is housed in 32.

The photosensitive drum IO whose circumferential surface has been cleaned in this way
is charged again by the charger 20 and starts forming a new image, and at the same time the conductive bristle brush +10 is released from the rubbing state.

On the other hand, the recording paper to which the toner image has been transferred in the transfer section is separated from the circumferential surface of the photoreceptor drum 10 and transferred to the fixing device 60.
will be sent to. Reference numeral 63 denotes a pair of heat rollers for fixing, and numeral 64 denotes a pair of paper ejecting rollers. The recording paper on which the toner is melted and fixed by the pair of heat rollers 63 is ejected from the fixing device by the pair of paper ejecting rollers 64.

Reference numerals 73 and 74 are paper ejection guides for guiding the recording paper ejected by the pair of paper ejection rollers 64 to the upper part of the main body of the apparatus. The sheets are discharged and stacked on the tray 75 with the surface facing downward.

Next, the configuration of the developing device 600 will be explained.

As described above, the device 600 includes a developing device 611A containing Y (yellow) developer, a developing device 611B containing M (magenta) developer, a developing device 611C containing C (cyan) developer, and a developing device 611C containing C (cyan) developer. This is more important than developing device 611D, which stores BL (black) developer. Each of the Y and M%C developing devices has one cartridge frame 60.
2 to form a color developing device and guide rail 7.
Clamshell opening/closing section 700 formed on the upper part of the base section 800 of the image forming apparatus l guided by 13A and 713B
It is set so that it can be attached and detached from the entrance/exit window 713 provided in the frame 701. On the other hand, the black developer storage developing device 6110 is set to be independently attachable and detachable to the opening/closing section 700 from the entrance/exit window 713 along the guide rail 713G.

Since the configuration of each of the four developing units is the same, the configuration of 611A will be explained. The aforementioned developing roller (developing sleeve) 612 and stirring rollers 614 and 615 are housed inside the container 603 of the developing device, and at both ends of the developing roller 612 there are outer diameter portions 6 that are a certain amount larger than the outer diameter of the roller 612.
13 are provided in the same manner. Also, on the right side of the container 603 is a gear train 630 for transmitting drive to each of the rollers.
A toner receiving port 62 is provided on the left side of the container 603.
1 is open.

Then, a spring 618 is applied along a rail 619 provided in the container 603 so as to close the receiving port 621.
A mouth opening/closing member 618 is provided which is biased by a guide bin 616.

The container is connected to the developing unit 611 by a spring 625 (this may be a plate spring or a helical spring).
A is the outer diameter portion 613 at both ends of the developing roller 612 and the photoreceptor 10
It should be pressed against the drawing. This allows the gap between the developing roller 612 and the photoreceptor drum 10 to maintain an optimum gap for forming a magnetic brush.

Next, the toner replenishment tank 200 and toner replenishment device 250
I will explain about.

As shown in FIGS. 2 and 3, the tank 200 stores toner in a frame 701 of a clamshell opening/closing portion 700.
, M, C, and BL containers 201A of the same shape.

201B, 201C, and 201D are arranged in one row. Then, the gears 205A, 2 are driven by the drive motor 205.
06, 207, and each of the toner containers 20 through 208A.
The stirring shafts 1A, 201B, 201C, and 201D and the spiral rotating shaft 208 are made rotatable. The spiral rotating shaft 208 is connected to the toner supply port 20 of the tank 200.
9, and the supply conveyance port 209 has 272A, 27
One end of each hose represented by 2B, 272C, and 272D is connected, and a flexible spiral member 2 connected to the spiral rotation shaft 208 is contained in the hose.
71 is provided, and as the spiral rotation shaft 208 rotates, rotation is freely transmitted to the member 271 in the rotational direction of the shaft, and toner is conveyed.

The other end of each hose is connected to an introduction pipe 259 to a distribution container 251 for each color toner of the toner replenishing device 250. A toner supply port 257 is opened in the container 251 . The container 251 is provided with a rail 254 and an opening/closing member 258 that slides on the rail 254. The opening/closing member 2 is connected to the opening/closing member 2 by a pin 252 and a spring 253 provided on an extension 251A at the bottom of the container 251.
58 is always biased to the right. The supply port 257 is normally closed by the port opening/closing member 258.

The bottom extension 251A of each dispensing container 251 of this toner replenishing device is fitted with bottles 266, 267 and 264 that fit into elongated holes 708, 709 provided in the frame 701 of the clamshell opening/closing section 700, and , is coupled and fixed to a bent portion 262 of a plate 261 that is slidable in the direction of the elongated hole.

On the other hand, the frame 701 of the clamshell opening/closing section 700 is connected to a bearing section 802 provided on the frame 801 of the base section 800.
The opening/closing operation is made possible by the rotating support shaft 702 that fits into the opening/closing operation.

In addition, bottle fitting grooves 703A, 703B, 703C, 70
The cam lever 703 with 3D is the clamshell opening/closing part 7.
Pins 704 and 705 fixed to the frame 701 of 00, pin 266 fixed to the plate 261 and the base part 80
It is provided so as to fit into a bin 805 fixed to a frame 801 of 0.

When the clamshell opening/closing portion 700 is opened from the side view shown in FIG. 1 to the perspective view shown in FIG. move through the long holes 708 and 709, and the plate 261 with those pins moved to the left.

In this way, the dispensing container 252 of the toner replenishing section, which is fixed to the bent portion 262 of the plate 261 by the bottom extension 252A, can also be moved to the left. As a result, the container 252 is separated from the container 603 of the developing device, and the opening/closing member 258 closes the replenishment hole 257 by the biasing force of the spring 255 to prevent toner from spilling from the distribution container 251. become.

On the other hand, the toner receiver of the container 603 of the developing device 600 is
21 is also closed by sliding the mouth opening/closing member 618 on the rail 619 by the biasing force of the spring 617. Further, the toner in the container 603 of the developing device 600 is also prevented from spilling.

In this way, when the clamshell opening/closing section 700 is open, the toner supply section 250 moves backward and closes the supply port 257, and the toner receiving port 621 of the container 603 of the developing device 600 is also closed, so that toner spillage is automatically prevented. completely prevented.

When the clamshell opening/closing section 700 is open in this manner, the cartridges consisting of the three color developing devices of Y, M, and C are combined into one cartridge and integrated as a unit from the entrance/exit window 713 of the clamshell to the guide rail. 713
It can be easily attached and detached by being guided by A and 713B.

Further, the developing device 611D for black developer can be easily attached and detached as one cartridge by being guided by the guide rail 713C of the old entry/exit window 713 of the frame 7 of the clamshell opening/closing section.

Also, Cleaner 100. Charger 20. Front charge electrode 90. The photosensitive drum cartridge 500 including the toner collecting section 130 and the like is also shown in the perspective view of FIG. , the cartridge 500 is guided and slid by guide parts 510A and 510B on both sides to facilitate attachment and detachment, and the drum center bin 11 is guided by guide parts 510A and 510B on both sides to facilitate attachment and detachment.
'l can be set to fit in a predetermined position.

Further, the leg portions 503 and 504 of the cartridge are provided to facilitate inspection and cleaning when the cartridge 500 is pulled out from the clamshell opening/closing portion 700 and placed on an arbitrary table, making it easy to handle.

In this way, each cartridge can be easily installed and removed while the clamshell opening/closing section is open for maintenance inspection, and it is also easy to replace the cartridge with a new one. Furthermore, by dividing the cartridge into three parts, it is no longer possible to load toner of each color in the wrong order. This is especially true not only for full-color images but also for multi-color images.In addition, by attaching and detaching the drum cartridge containing the photoreceptor drum and the developer cartridge orthogonally to each other, the loading and assembly operation is safer and more reliable than parallel loading. It became a thing. In particular, the structure is simpler if the photoreceptor cartridge is attached and detached before the developer cartridge is attached and detached than if it is done the other way around. This is because if the process is carried out in the reverse order, it is necessary to construct a configuration in which the developing roller and the like are removed so that the surface of the photoreceptor is not scratched during attachment and detachment of the developing device. Although this does not make the structure that complicated, it is preferable to have a method that does not require such measures.

In this embodiment, each toner replenishment tank 200 and each toner replenishment device 250 are attached to each developing device, but the toner replenishment tank 200 and toner replenishment device 250 are not provided separately. First, you can store enough toner in the developing device for the life of the developing device, and when it is used up, you can discard the old developing device along with the cartridge and replace it with a new developing device in a new cartridge. .

Although each color developing device is placed in one cartridge and the black cartridge is placed in another cartridge, it is possible to consider the replacement period depending on the frequency of use. However, when used as a multicolor image forming apparatus, Depending on the user's usage, a certain color may be used more frequently,
At this time, it is also possible to rub the child's cartridge into the cartridge so that the developer of that color can be replaced extra quickly.

〔Effect of the invention〕

According to the present invention, the areas around the photoreceptor drum and developer of the image forming apparatus are configured as cartridges for each unit and can be installed and removed, making it easy to disassemble each function, making it easy to observe every corner of the inside of the apparatus. It has been expanded so that inspection and cleaning operations are certainly easier. In addition, the photoreceptor and the developer can be attached and detached at right angles, and there is no fear that the developer will cause damage to the surface of the photoreceptor drum when it is attached or detached. Image quality is now always available.

[Brief explanation of drawings]

FIGS. 1 and 2 show one embodiment of the present invention, and FIG. 4 is a perspective view of one embodiment of the present invention when the clamshell is opened. "O... Photosensitive drum 11... Drum center bin 20... Charging device 30... Laser writing system unit 60... Fixing device 80... Transfer roller 90
. . . Front charger 100 . . Cleaning device 130 . . . Toner collection unit 200 .
4... Leg portions 510A, 510B... Guide portion 6
00...Developing device 602...Cartridge frame 611A...Y developer containing developing device 611B...M developer containing developing device 611C...C developer containing developing device 611D...Black developer Accommodating developer 700...Clamshell opening/closing part 701...Frame 702...Rotation shaft 71
2... Guide rail 713... Entrance/exit window 713A,
713B, 713C...Guide rail 800...Base! 801... Frame 802... Bearing part

Claims (1)

[Claims] In a clamshell type electrophotographic image forming apparatus, a drum cartridge containing a photoreceptor drum and a developing cartridge containing a developing device are provided separately, and the drum cartridge is attached and detached in a direction perpendicular to a pivot shaft of a clamshell opening/closing part. 2. A clamshell type electrophotographic image forming apparatus, wherein the developer cartridge is installed and removed in a direction parallel to the rotational support shaft.