JPH04133069A - Color image forming device - Google Patents

Abstract

PURPOSE:To improve maintenance and jamming process by providing a belt shaped photosensitive body and by providing a multiple number of developing devices and a cleaning device in its periphery integrally, and by detaching them in the direction which is approximately in parallel with the protruding installment direction. CONSTITUTION:The photosensitive body belt 1, an electrifying device 6, each developing device, and the cleaning device 13 are integrally assembled to an independent process unit 30, and slid in the direction parallel to the protruding installment direction and detached. Furthermore, the jamming process of the transfer material is carried out by greatly opening a transportation path by rotating a guide plate 15A counter clockwise after opening a side cover 60. Thus, the processing unit 30 can be easily detached, the jamming processing of the transfer material, toner replenishing and recovery can be carried out, improving the handling ease of the device.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an electrophotographic color image forming apparatus for forming an image on a transfer material such as a copying machine or a printer.

[Background of the invention]

In image forming devices such as monochrome analog copying machines that use electrophotography and copying machines and printers that use semiconductor laser and LED scanning systems, consumption of various photoreceptors, developers, cleaning members, and developer toner that have a useful life is reduced. A device configured such that part of the image forming means is made into a cartridge for replenishment and replacement at times, and the member that integrates the main parts of the image forming means is taken out of the device for maintenance or replacement. is proposed. Furthermore, various configurations have been proposed in which the conveying path of the transfer material on which an image is formed by the image forming means is opened so that the transfer material can be easily handled in case of a jam.

A typical configuration of these is as disclosed in Japanese Patent Publication No. 58-54392, in which the photoreceptor drum, developer, cleaner, etc. are integrally attached to a support member and can be pulled out from the main body of the apparatus. Proposals were made to make replacement and repair easier, and the next step was to integrate the main parts of these image forming means and make them disposable in Japanese Patent Application Laid-Open No. 57-15.
4255, and Japanese Patent Laid-Open No. 147366/1989 discloses a printer configuration that uses a similar disposable cartridge and forms a latent image on a photosensitive drum by dot exposure scanning writing using a semiconductor laser. There is.

Further, these publications disclose a structure in which the upper housing of the split structure is opened to open the transfer material conveyance path and take out the transfer material in the event of a jam. A structure is adopted in which a disposable process cartridge is replaceably disposed in an upper housing having a two-part structure, and is intended to improve the workability of cartridge replacement and ease of jam removal. In addition, with emphasis on ease of replacement of process cartridges, mainly replenishment toner cartridges and recovery toner relining cartridges, the structure is divided into two parts. A method with improved properties is disclosed in JP-A-58-1161.

In addition, the above structure is made vertical, and JP-A-63-2
No. 44058, No. 63-244059, No. 63-24
No. 4064, Japanese Unexamined Patent Publication No. 1-179168, etc., have been proposed, and these are aimed at improving the same direction operation and jam handling.

[Problem that the invention seeks to solve]

However, if the main body of the device is divided into two parts and the transfer material conveyance path is open at the top and bottom, the heavy cartridges have to be installed and removed at a high position, making it difficult to operate, and also from a structural point of view. There were also problems in that the strength was insufficient, the durability was poor, and the precision between the members was reduced.

The present invention solves this problem and improves it, making it extremely easy to install and remove the process cartridge and open and close the transfer material conveyance path, making it easy to maintain process materials and clear jams in the transfer material. The purpose of this invention is to provide a color image forming apparatus with a robust structure.

[Failure to solve the problem]

The above object is to provide a color image forming apparatus having a removable process unit in which a stretched belt-shaped photoreceptor and a plurality of developing devices and a cleaning device are integrally provided on the peripheral edge of the belt-shaped photoreceptor, the above-mentioned process unit being provided above the process unit. This is achieved by a color image forming apparatus characterized in that it has a reading device at the top and a paper feeding device at the bottom, and the process unit is attached and detached in a direction substantially parallel to the direction in which the belt-shaped photoreceptor is stretched.

〔Example〕

An embodiment of the color image forming apparatus of the present invention is shown in FIGS. 1 to 5.

In FIG. 1, l is a flexible photoreceptor belt that is a belt-shaped photoreceptor, and the photoreceptor belt 1 is connected to rotating rollers 2 and 3.
The rollers 2 are conveyed clockwise by the drive of the rotating rollers 2.

Reference numeral 4 denotes a support member or guide member fixed to the main body of the apparatus so as to be inscribed in the photoreceptor belt 1, and the photoreceptor belt 1 is kept in a tensioned state by the outward biasing action of the rotary roller 3. The inner circumferential surface of the guide member 4 is
Let it rub.

Therefore, the photoreceptor on the outer circumferential surface of the photoreceptor belt is always maintained at a constant position relative to the surface of the guide member 4 even during transportation, making it possible to form a stable image forming surface.

Reference numeral 6 denotes a scorotron charger as a charging means, 7 a laser writing system unit as an image exposure means, 8 to 11 a plurality of developing devices each containing a developer of a specific color, and each of these image forming means is provided with a guide. It is disposed opposite to the peripheral edge of the photoreceptor belt 1 with the member 4 facing back.

The laser writing system unit 7 is housed in a holding casing 70 having a slit-shaped exposure opening 70A on its upper surface, and is incorporated into the main body of the apparatus.

In addition to the optical system shown in the drawings, the laser writing system unit 7 may also include an optical system that integrates a light emitting section and a convergent light transmission body.

Each of the developing units 8.9.10.11 accommodates, for example, yellow magenta, cyan, and black developers, respectively, and is provided with each developing sleeve that maintains a predetermined gap with the photoconductor bell l-1. It has a function of making a latent image on the body belt 1 visible by a non-contact development method. Unlike contact development, this non-contact development has the advantage of not interfering with the movement of the photoreceptor belt.

12 is a transfer device, 12A is a static elimination bar, 13 is a cleaning device, and a blade 13A and a toner conveying roller 13B of the cleaning device t13 are connected to the photoreceptor belt l during image formation.
The photoreceptor belt 1 is kept in a position apart from the surface of the photoreceptor belt 1, and is pressed against the surface of the photoreceptor belt 1 as shown in the figure only during cleaning after image transfer.

The process of forming a color image by the color image forming apparatus is performed as follows.

When the copy button is operated, image reading system A at the top of the main body of the apparatus starts reading the image of the document.

Image reading system A includes halogen lamp 2OA and mirror 20B.
Carriage 20 with attached mirror 21A and mirror
21B, an imaging lens 22, and a collar 〇〇D23. By the exposure scanning, image signals for each color of yellow and magenta cyan of the original image are obtained.

The obtained image signal is subjected to arithmetic processing in an image data processing section to create image data, and is input to the main body of the color image forming apparatus shown in the embodiment of FIG. 1, which is a recording section.

First, when an image signal is input to the laser writing system unit 7, in the laser writing system unit 7, a laser beam generated by a semiconductor laser (not shown) is rotated and scanned by a polygon mirror 7B rotated by a drive motor 7A. mirrors 7D and 7E via fθ lens 7C.
The optical path is bent by this, and the light is projected onto the circumferential surface of the photoreceptor belt 1, which has been charged in advance by a charger 6, which is a charging means, to form a bright line.

On the other hand, when scanning is started, the beam is detected by the index sensor, modulation of the beam by the first color signal is started, and the modulated beam scans the circumferential surface of the photoreceptor belt 1. Therefore, a latent image corresponding to the first color is formed on the circumferential surface of the photoreceptor belt l by the main scanning by the laser beam and the sub-scanning by the conveyance of the photoreceptor belt l-1 in synchronization with the reading scan of the original image. go. This latent image is developed by a developing device 8 loaded with yellow (Y) toner (developing medium) of the developing means, and a toner image is formed on the drum surface. The obtained toner image, while being held on the drum surface, passes under a cleaning device 13, which is a cleaning means, which is separated from the peripheral surface of the photoreceptor bell l-1, and enters the next copy cycle.

That is, the photoreceptor bell) 1 is charged again by the charger 6, and then the second color signal output from the signal processing section during the second reading scan of the original image is input to the writing system unit 7. As in the case of the first color signal described above, writing is performed on the drum surface in synchronization with the second reading scan to form a latent image. The latent image is developed by a developer 9 loaded with magenta (M) toner as a second color.

This magenta (M) toner image has already been formed6.
It is formed in the presence of the yellow (Y) toner image described above.

IO is a developing device having cyan (C) toner, which forms a cyan (C) toner image on the drum surface based on a control signal generated by a signal processing section.

Furthermore, 11 is a developing device having black toner, and forms a black toner image superimposed on the belt surface by the same process. These developing units 8, 9, 10 and 11
A direct current or even alternating current bias is applied to each sleeve, and jumping development is performed using a two-component developer, which is a developing means, and development is performed without contact on the photoreceptor belt 1 whose base is grounded. It has become. Incidentally, as the development, non-contact development using a -component developer can also be used.

In this way, the four-color toner images formed on the circumferential surface of the photoreceptor belt l in synchronization with the four reading scans are sent via the paper feed guide 15 from the paper feed cassette 14^ or 14B in the transfer section. The image is transferred to the transferred transfer material.

That is, the top layer of the transfer material stored in the paper feed cassette 14A or 14B is carried out by the rotation of the paper feed roller 16A or 16B, and then transferred to the timing roller 17.
The photoreceptor is supplied to the transfer device 12 through the photoreceptor belt 1 in synchronization with the image formation on the photoreceptor belt 1.

The transfer material that has undergone image transfer and static electricity removal is transferred to the rotating roller 2.
The photoreceptor belt 1 is reliably separated from the photoreceptor belt 1, which suddenly changes direction along the direction, and moves upward, and after the image is fused by the fixing roller 18, it is ejected via the paper ejection roller 19 onto the tray 19A.

On the other hand, the photoconductor bell (1) which has completed the transfer to the transfer material continues to be conveyed to the blade 13A and the toner conveying roller 13B.
After the toner was removed, the blade 13A was removed again after the toner was removed, and a little later, the toner conveying roller 13B deposited it on the tip of the blade 13A]
- Leveling the toner; Afterwards, the toner conveying roller 13B is separated and a new image forming process begins.

The photoreceptor belt 11, the charger 6, each developer, and the cleaning device 13 are integrated into an independent process unit 30, and as shown in FIG. It is inserted into and removed from the inside of the device by sliding parallel to it.

The mounting position of the process unit 30 in the apparatus main body is such that the image reading system A, which is a reading device, is installed above it, and the paper feeding device, which is the paper feeding force cell I-14A, is installed below it.
and 14B, and is located at a height that facilitates attachment/detachment operations, and is also suitable for linking functions with other process materials.

As shown in FIG. 3, the process unit 30 is equipped with a rail member 31 having a convex cross-section on both sides thereof, and is inserted into and engaged with a guide member 32 having a concave cross-section installed inside the apparatus. It is attached to the device by doing this.

The position of the process unit 30 described in 1ttJ is determined by the contact of the end portion 31A of the rail member 31 with the guide member 32, and at the same time, the top portion 33A of the locking plate 33 provided on the main body side is engaged with the notch portion 31B of the rail member 31. They are fixed by mating, and each of the process materials contained therein is set in a position that enables respective image formation.

The process unit 30 includes the cleaning device 1
A handle 30A for inserting and removing the process unit 30 is derived by deforming and protruding a part of the outer wall forming the process unit 30.

Therefore, the process unit 30 can be easily attached to and detached from the main body of the apparatus without additionally installing a separate handle or the like, and since it can be stored compactly, there is also a side cover 40 for the exterior on the front side. It is also possible to install the .

A portion of the locking plate 33 is a release lever 33B that protrudes to the side of the unit, and by pushing down the release lever 33B, the locking plate 33 is retracted downward against the bias of the tension spring 34. I can do it.

Therefore, the process unit 30 can be easily taken out from the cleaning apparatus 13 by opening the cover 40 and pushing down the release lever 33B, as shown in FIG.

Further, when the process unit 30 is attached or detached, the connecting portions between each internally disposed developing device and each toner replenishment hopper installed within the apparatus main body are automatically connected or separated.

That is, the main body of the apparatus includes toner supply hoppers 80 and 9 that accommodate yellow, magenta, cyan, and black toners.
0.1008 and 110 are arranged in parallel along the attachment/detachment direction of the process unit 30, and each supply pipe 80A, 90A, lOOA and l
10A, and is connected to each corresponding developing device via the above-mentioned connecting portion.

The connecting portion is connected to each of the supply pipes 8 as shown in FIG.
Upper connecting plate PA to which 0A, 90A, 100^ and ll0A are fixed, and each supply pipe 8A, 9 on the developer side
A, IOA, and IIA are fixed to the lower connecting plate PB, and as the lower connecting plate PB moves as the process unit 30 is attached or removed, the toner receiving ports 8B, 9B, and IOB on the lower connecting plate PB side are connected to each other. and IIB are the toner drop ports 80B, 90B, 10 on the upper connecting plate PA side.
0Bj'; and ll0B, the toner is replenished or evacuated to interrupt the toner supply.

Each of the above-mentioned toner drop ports is provided with guide rails 1001 and 100.
2^, ], 002B is covered by a shirt top plate 1000 that is slidably supported.

The drain plate 1000 has four shutter holes 1000A at equal intervals corresponding to each of the toner drop ports.
However, due to the biasing force in the opposite direction of the arrow by the tension spring 1003, each toner falling port is kept closed at all times without aligning with each of the toner falling ports.

On the other hand, each of the above-mentioned toner receiving ports has guide rails 2001 and 2.
It is covered by a shirt shirt plate 2000 which is slidably supported by 002A and 2002B.

The shutter plate 2000 has four shutter holes 200OA opened at equal intervals corresponding to each toner receiving port, but due to the bias in the direction of the arrow by the tension spring 2003, the shutter holes 200OA do not align with the respective toner receiving ports. Each toner receiving port is kept closed at all times.

When the process unit 30 is installed at a fixed position in the apparatus main body, the connecting plate PB is slid in the direction of the arrow and is located directly below the connecting plate PA, so that the spring hook on the connecting plate PB side is pinned. 2004 presses the rising portion 1004 of the shutter plate 1000 on the side of the connecting plate PA and slides the shutter plate 1000 to align the shutter hole 1000A with each toner fall port to open the shutter hole 1000A, and then the shutter hole 1000A on the side of the connecting plate PA Rise 520 of the side shirt plate 2000
A spring hook 05 on the connecting plate PA side is pressed by a pin 1005, and the shutter plate 2000 slides, aligning the shutter hole 2000 with each toner receiving port and opening the shutter hole 2000, allowing toner to be replenished.

On the other hand, residual toner removed from the photoreceptor belt 1 by the cleaning device 13 is collected in a waste toner cartridge 34 built into the unit 30, and is discarded or replaced with the entire cartridge when the unit 30 is taken out.

Further, in the above-mentioned apparatus, the conveyance path of the transfer material can be opened from the side opposite to the attachment/detachment of the process unit 30.

That is, the paper feed guide 15 includes a guide plate 15A that is rotatable about the shaft S and a guide plate 1 that is fixed to the main body of the apparatus.
5B, and the transfer device 12, the neutralization bar 12A, and the pressure roller 17A of the timing roller 17 are mounted and supported on the guide plate 15A side, so the side cover 60 must be removed when clearing a transfer material jam. By opening the lid and rotating the guide plate 15A counterclockwise, the conveying path for the transfer material is wide open, and processes such as its removal can be easily performed.

Note that the guide plate 15A is reliably locked and held at the set position by a click device (not shown) or the like at the position shown in FIG. 1 constituting the paper feed guide 15.

FIG. 5 shows a transfer drum type color image forming apparatus as another embodiment of the present invention.

The photoreceptor belt 101 and the process unit portion disposed around its periphery are almost the same as those in the previous embodiment, but the transfer drum 200 is placed in contact with the transfer portion of the photoreceptor belt 101. 200 is photoreceptor belt 1
01 and rotates in the direction of the arrow (counterclockwise). A transfer material is wrapped around the outer periphery of the transfer drum 200,
The toner image is transferred onto the wrapped transfer material, the transferred f-toner image is superimposed, and then separated from the transfer drum 200 and discharged onto the device after fixing.

A charger 201 is provided at the peripheral edge of the transfer drum 200 to electrostatically attract the transfer material. A winding member 202 for mechanically winding the transfer material around the transfer drum 200 is provided, and the winding member 202 has a roller at its tip, and the winding member 202 has a roller only when it is first wound around the transfer drum 200. come into contact with Further, a gripper 203 is provided on the peripheral surface of the transfer drum 200, and acts to hold the leading edge of the transfer material that is synchronously conveyed. 204 is a transfer device, photoconductor bell l-10
1 is electrostatically transferred onto a transfer material. 20
5 is a separation electrode, and 206 is a separation claw. Also 207
A cleaner is capable of coming into contact with and separating from the cleaner, and is used to remove toner adhered to the transfer drum 200 after the transfer material has been separated.

The transfer material discharged from the paper feed cassette 114A or 114B enters the transfer drum 200 charged by the charger 201 while maintaining synchronization, is wound around by the winding member 202, and the leading edge of the transfer material is held by the gripper 203. The yellow (Y) toner image formed on the photoreceptor bell (101) is transferred onto a transfer material by a transfer device 204 at the transfer section. After completing the first transfer, the transfer drum 200 continues to rotate, and in the second rotation, a magenta CM)
the toner image, and the cyan (C) toner image in the third rotation.
Black (BK) toner images are sequentially transferred onto the rotation stitches in an overlapping manner.

When the transfer of the four-color toner image is completed, the transfer material is neutralized by a separation/elimination electrode 205 , the leading edge of the transfer material is released from being held by a separation claw 206 , and separated and conveyed to the fixing roller 118 .

In the image forming apparatus of this example, the transfer drum 200 is located on the apparatus main body side and is not included in the process unit 130 which is movable and removable. Therefore, when the process unit 130 is attached or detached, the transfer drum 200 is moved slightly to the left and retracted from the photoreceptor belt 101.

〔Effect of the invention〕

The present invention realizes a structure in which the process unit can be attached and detached with extremely easy operation without compromising the strength and durability of the main body of the apparatus.Furthermore, it is possible to remove jams in the transfer material, replenish and collect toner, etc. A practical color image forming apparatus that is easy to handle and always produces high-quality images has been provided.

[Brief explanation of drawings]

1, 2, and 5 are cross-sectional configuration diagrams of a color image forming apparatus of the present invention, and FIGS. 3 and 4 are perspective views showing essential parts of the apparatus. 1.101... Photoreceptor belt 6... Charger 7.107... Laser writing system unit 8.9.10
．． 11...Developer

Claims (2)

[Claims] (1) In a color image forming apparatus having a removable process unit in which a stretched belt-shaped photoreceptor and a plurality of developing devices and a cleaning device are integrally provided on the peripheral edge of the belt-shaped photoreceptor, above the process unit. A color image forming apparatus comprising a reading device and a paper feeding device below, and wherein the process unit is attached and detached in a direction substantially parallel to the direction in which the belt-shaped photoreceptor is stretched. (2) The color image forming apparatus according to claim 1, wherein the process unit is attached and detached from the cleaning device side.