JPH04321056A - Image forming device - Google Patents

Abstract

PURPOSE:To increase and stabilize the attaching accuracy of a laser writing system unit housed in a device, and at the same time to easily execute attaching/detaching operation to a position where the unit is attached. CONSTITUTION:The device is constituted in such a way that engaging metallic part 71 and attaching metallic parts 72 are provided on the bottom surface of a housing 70 in which the laser writing system unit 7 is housed, on the other hand, a pair shaft members 110 and 120 in parallel is installed in the device, the engaging metallic parts 71 are engaged with the shaft member 110, and the attaching position of the laser writing system unit 7 can be simultaneously controlled in up-and-down, back-and-forth, and right-and-left directions by the easy operation to screw the attaching metallic parts 72 to the shaft member 120.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus in which process materials for image forming, including an image carrier, are integrated into a cartridge and can be attached to and removed from the cartridge.

0002

2. Description of the Related Art As an apparatus for obtaining color images by electrophotography, a latent image is formed on a photoreceptor drum or a photoreceptor belt in accordance with the number of separated colors of an original image, and development with color toner is repeated. This is a method of superimposing color toner images on a drum or belt and then transferring them to obtain a color image. The basic process of forming multicolor images is disclosed in Japanese Patent Application Laid-open Nos. 60-75850, 60-76766, 60-95456, 60-95458, and 60-95458 by the present applicant.
This is disclosed in Japanese Patent No. 0-158475 and the like.

[0003] In a multicolor image forming apparatus that obtains a color image by superimposing the images, a plurality of developing devices containing different colored toners are arranged around the periphery of the photoreceptor. Generally, a photoreceptor is rotated multiple times to develop a latent image on the photoreceptor to obtain a color image.

[0004] Regarding such an image forming apparatus, a part of the image forming means is made into a cartridge in order to replenish and replace various photoreceptors, developer carriers, cleaning members, and developer toner which have a useful life when they are exhausted. A system has been proposed in which a member that integrates the essential parts of these image forming means is taken out of the apparatus for maintenance or replacement. Furthermore, various configurations have been proposed in which the conveyance path of the transfer material on which an image is formed by the image forming means is opened to make it easier to take out the transfer material when clearing a jam. moreover,
In digital image forming apparatuses, a laser writing system is used as a means for forming a latent image on a photoreceptor, but the laser writing system is also unitized to facilitate cleaning and inspection. An image forming device with a clamshell structure has been proposed, which can be separated into two parts by opening the top and bottom, and can be housed in a detachable manner, making it easy to perform the above-mentioned maintenance as well as to dispose of jammed paper. has been done.

[0005]

[Problems to be Solved by the Invention] However, dividing the main body of the device into two causes concerns about maintaining the strength or durability of the device itself, and it is also necessary to maintain the positional relationship between the divided pieces of equipment with high accuracy in the storage position. It is considered structurally difficult to restore.

[0006] As a result of solving this problem and improving the present invention,
An image forming apparatus that maintains and improves the strength of the main body of the apparatus, allows easy attachment and detachment of the process cartridge and writing system unit, and furthermore allows position regulation with extremely high precision in the storage position. The purpose is to provide

[0007]

[Means for Solving the Problems] The above object is to provide a process in which a developing section is provided at least on a photoreceptor and its periphery in an image forming apparatus having a main frame of left and right panels configured in two parts or in one piece. The cartridge, the paper feed cassette, and the laser writing unit are all attached to the main body in the same direction, and the laser writing unit is guided and positioned and fixed by two shafts installed between the left and right panels. This is accomplished by an image forming device.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an image forming apparatus according to the present invention is shown in FIGS. 1 to 3.

In FIG. 1, reference numeral 1 denotes a flexible photoreceptor belt, which is a belt-shaped photoreceptor. Transported clockwise.

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;
The photoreceptor belt 1 is brought into a tensioned state by the outward biasing action of the rotary roller 3, so that its inner circumferential surface slides against the guide member 4. Therefore, the photoreceptor belt 1
The photoreceptor on the outer circumferential surface of the photoreceptor is always maintained at a constant position relative to the surface of the guide member 4 during transportation, making it possible to form a stable image forming surface.

6 is a scorotron charger as a charging means; 7
8 to 1 are laser writing system units serving as image exposure means;
Reference numeral 1 denotes a plurality of developing means, that is, developing devices, each containing a developer of a specific color, and each of these image forming means is arranged opposite to the outer circumferential surface of the photoreceptor belt 1 with the guide member 4 as its back surface. will be established.

Each of the developing devices 8, 9, 10, and 11 accommodates, for example, yellow, magenta, cyan, and black developers, respectively, and is provided with a developing sleeve that maintains a predetermined gap from the photoreceptor belt 1. It has a function of making the latent image on the photoreceptor 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.

Reference numeral 12 denotes a transfer device, 12A denotes a charge eliminating bar, and 13 denotes a cleaning device, in which a blade 13A and a toner conveying roller 13B are kept at a position apart from the surface of the photoreceptor belt 1 during image formation. It is pressed against the surface of the photoreceptor belt 1 as shown in the figure only during post-transfer cleaning.

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

First, the formation of a multicolor image according to this embodiment is performed according to the following image forming system. That is, data obtained by a color image data input section in which an image sensor scans an original image is subjected to arithmetic processing in an image data processing section to create image data, which is temporarily stored in an image memory. The image memory is then taken out during recording and input to a recording section, for example, the color image forming apparatus shown in the embodiment of FIG.

That is, when a color signal output from an image reading device separate from the printer is input to the laser writing system unit 7, the color signal is generated by a semiconductor laser (not shown) in the laser writing system unit 7. The laser beam is transmitted to a polygon mirror 7 rotated by a drive motor 7A.
B, it is rotated and scanned by the mirror 7 via the fθ lens 7C.
The optical path is bent by D and 7E, and the light passes through a cylindrical lens 7F and a mirror 7G, and is projected onto the circumferential surface of the photoreceptor belt 1, which has been charged in advance by a charger 6 serving as 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 1 by main scanning by the laser beam and sub-scanning by the conveyance of the photoreceptor belt 1. This latent image is yellow (Y) in the developing means.
The toner (developing medium) is developed by the developing device 8 loaded with the toner (developing medium), and a toner image is formed on the belt surface. The obtained toner image, while being held on the belt surface, passes under a cleaning device 13, which is a cleaning means, which is separated from the peripheral surface of the photoreceptor belt 1, and enters the next copy cycle.

That is, the photosensitive belt 1 is charged again by the charger 6, and then the second color signal outputted from the signal processing section is inputted to the writing system unit 7, and the above-mentioned first color signal Writing is performed on the belt surface in the same manner as in the case of , and a latent image is formed. The latent image is developed by a developer 9 loaded with magenta (M) toner as a second color.

This magenta (M) toner image is formed in the presence of the previously formed yellow (Y) toner image.

A developing device 10 has cyan (C) toner, and forms a cyan (C) toner image on the belt surface based on a control signal generated by a signal processing section.

Further, numeral 11 denotes a developing device containing black toner, which forms a black toner image superimposed on the belt surface by the same process. These developing devices 8, 9, 1
Direct current or even alternating current bias is applied to each sleeve 0 and 11, and jumping development is performed using a two-component developer, which is a developing means, and non-contact development is performed on the photoreceptor belt 1 whose base is grounded. It is about to be done. Note that as the development, non-contact development using a one-component developer can also be used.

The color toner image thus formed on the circumferential surface of the photoreceptor belt 1 is transferred to a transfer material fed from the paper feed cassette 14 via the paper feed guide 15 at the transfer section.

That is, the uppermost layer of the transfer material stored in the paper feed cassette 14 is carried out by the rotation of the paper feed roller 16, and transferred to the photoreceptor belt 1 via the timing roller 17.
It is supplied to the transfer device 12 in synchronization with the above image formation.

The transfer material that has undergone image transfer and static electricity removal is reliably separated from the photoreceptor belt 1, which suddenly changes direction along the drive roller 2, and heads upward via the suction type conveyor belt 17A. After the image is fused by the fixing roller 18, the sheet is discharged via the discharge roller 19 onto a tray formed on the top lid 20.

On the other hand, the photoreceptor belt 1 that has completed the transfer to the transfer material continues to be transported to the cleaning device 1 with the blade 13A and the toner transport roller 13B in pressure contact.
3, the remaining toner is removed, and after the removal is finished, the blade 13A is pulled away again. A little later, after the toner conveying roller 13B smoothes out the toner accumulated on the tip of the blade 13A, the toner conveying roller 13B is removed.
B is separated and a new image forming process begins.

The photosensitive belt 1, the charger 6, each developing device, and the cleaning device 13 are incorporated into an independent process cartridge 30 as process materials for image formation, and are integrally attached to and removed from the main body of the apparatus.

The laser writing system unit 7 is also integrated into the housing 70 and is attached to and removed from the main body of the apparatus in the same manner as the process cartridge 30.

The process cartridge 30 is slid and inserted from the upper right side through a guide device provided between the process cartridge 30 and the main body of the apparatus, and is brought into contact with a stopper and set at the mounting position.

On the other hand, the laser writing system unit 7 is attached to a support device described below and set at the device position.

The laser writing system unit 7 has a housing 70
The bottom surface thereof is provided with an engaging fitting 71 having L-shaped bent portions formed at both ends as shown in FIG. 2, and a mounting fitting 72 having an L-shaped cross section and a pair of insertion holes.

Also, inside the main body of the apparatus that houses the laser writing system unit 7, as shown in FIG. 110 and 120 are installed between the left and right panels 100.

The shaft members 110 and 120 are connected to the housing 70.
Flange member 110A for regulating the axial position of
and 120A are fixed in pairs, respectively, and the shaft member 120 is further provided with a pair of screw holes at horizontal positions.

When the laser writing system unit 7 is installed into the apparatus, it is inserted into the main body from the same direction as the process cartridge 30 and the paper feed cassette 14, and is first guided by the flange members 110A and 120A, and then is guided by the engaging metal. The tool 71 engages with the shaft member 110, and the bottom surface of the casing 70 is placed on the shaft member 120 to be in a horizontal state. In this state, the laser writing system unit 7 is shown in Figure 1.
The vertical and longitudinal positions of the

Next, when the tightening screw S passed through the insertion hole of the mounting bracket 72 is screwed into the screw hole of the shaft member 120, the engagement fitting 71 is pressed against the shaft member 110, and the laser writing system unit 7 is The position in the left and right direction in FIG. 1 is regulated, and at this position the laser writing system unit 7 is placed in a position to accurately project the laser beam reflected by the mirror G onto a predetermined writing position on the photoreceptor belt 1.

The laser writing system unit 7 can be easily taken out of the apparatus by removing the tightening screw S and pulling the handle 70A. At that time, the shaft member 120
Since it supports the weight while slidingly contacting the bottom surface of 0, removal work can be performed safely and easily.

Further, the process cartridge 30 is located above and below the laser writing system unit 7 at the mounting position.
The partition plates 130 and 170 serve as a tray to prevent toner from falling from the panel 100 and a reinforcing member for the panel 100, respectively.
is installed.

Although the present embodiment describes a color image forming apparatus using a belt-like photoreceptor, the present invention can be similarly applied to an apparatus using a drum-like photoreceptor as well as a monochrome image forming apparatus. The effects can be expected.

[0038]

[Effects of the Invention] According to the present invention, a simple support device is realized in which the strength of the main body of the device is sufficiently maintained, the operation of attaching and detaching the laser writing system unit is easy, and the device can be fixed accurately at the mounting position at all times. As a result, an image forming apparatus with high image writing accuracy and excellent maintenance workability has been provided.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional configuration diagram of an image forming apparatus of the present invention.

FIG. 2 is a cross-sectional configuration diagram of a laser writing system unit.

FIG. 3 is a side view of essential parts of the device.

[Explanation of symbols]

1...Photoreceptor belt
6... Charger 7... Laser writing system unit
7A...Drive motor 7B...Polygon mirror
7C...fθ lens 7D, 7E, 7G,...mirror
7F...Cylindrical lens 8, 9, 10, 11...Developer
14...Paper feed cassette 30...Process cartridge
70... Housing 71... Engaging metal fittings
72...Mounting bracket 100
…panel
110, 120...shaft member 110A, 120A...flange member
130, 170...Partition plate

Claims (1)

[Claims] [Claim 1] An image forming apparatus having a main body frame of left and right panels configured in two parts or as one unit, including a process cartridge, a paper feed cassette, and a laser writing device, each having at least a photoreceptor and a developing section on its periphery. An image forming apparatus characterized in that all the units are installed in the same direction on the main body, and the laser writing unit is guided and positioned and fixed by two shafts installed between the left and right panels.