JPH04307994A - Image forming apparatus - Google Patents

Abstract

PURPOSE:To simplify a wiring work by simplifying a wiring of a bundled wirings upon assembling and to prevent a radio wave fault due to generation of a high frequency wave by concentrically mounting a power source and a controller of an apparatus on a body panel. CONSTITUTION:A power source and a controller are assembled to be unified on a board as an electric unit 300, which is mounted on a body panel 100A of an apparatus, and the unit 300 is covered with a compact cover 300A made of a metal plate in a sealing state.

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 equipment for image forming, including an image carrier, is integrated into a cartridge and is detachable 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. There 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 that have a useful life when they are exhausted. In a digital image forming apparatus, a laser writing system is used as a means for forming a latent image on a photoreceptor, and the laser writing system is also unitized to facilitate cleaning and inspection. Similar to process cartridges, it is often stored in a removable manner in the main body of the apparatus.

On the other hand, the power supply and control section for operating and controlling each of the image forming means described above are installed in the main body of the apparatus, and the connectors are connected and removed when the cartridges and units are attached and detached.
The separation connects or disconnects power supply and control operation transmission to each image forming means.

[0006]

[Problem to be Solved by the Invention] However, the above-mentioned power supply and control unit include a unit that generates high frequency waves when activated, and there is a risk that the process operation of the device may malfunction or cause radio wave interference. It must be built into the device in a form that allows for electrical shielding.

[0007] As a result of solving this problem and improving the present invention,
The object of the present invention is to provide an image forming apparatus that facilitates wiring and integration by centrally arranging the power supply and control section on the panel surface of the apparatus main body, and further enables electrical shielding by extremely simple means. That is.

[0008]

[Means for Solving the Problems] The above object is to control the image forming apparatus in an image forming apparatus equipped with a process cartridge having a panel surface and having at least a belt-shaped photoreceptor that can be inserted and removed. This is achieved by an image forming apparatus characterized in that the board and the electrical components of the power supply are concentrated on one panel surface and shielded with a sheet metal.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an image forming apparatus according to the present invention is shown in FIGS. 1 to 4.

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 inscribed in the photoreceptor belt 1, and the photoreceptor belt 1 is brought into a tensioned state by the outward biasing action of the rotary roller 3, so that its inner periphery is The surface is rubbed against the guide member 4.

Therefore, the photoreceptors on the outer circumferential surface of the photoreceptor belt 1 are always maintained at a constant position relative to the surface of the guide member 4 even during conveyance, 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.

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, and 11 accommodates, for example, yellow, magenta, cyan, and black developers, respectively, and includes developing sleeves that maintain 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 static elimination 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 color image forming process 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, color signals output from an image reading device separate from the printer are transmitted 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, passes through an fθ lens 7C, and then is transmitted to a mirror 7D and The photoreceptor belt 1 has its optical path bent by 7E and 7F and is charged in advance by a charger 6 serving as a charging means.
is projected onto the circumferential surface 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 movement of the photoreceptor belt 1. This latent image is yellow (Y) in the developing means.
The developing device 8 loaded with toner (developing medium) forms a toner image 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 circumferential surface of the photoreceptor belt 1, and enters the next copy cycle.

That is, the photoreceptor 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 laser writing system unit 7, and the above-mentioned first color signal is input. Writing is performed on the belt surface in the same manner as in the case of signals, 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 top 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 onto 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.

FIG. 2 is a block diagram showing the power supply circuit and control circuit of the image forming apparatus.

When the process power is turned on by operating the main switch (not shown) of the apparatus, the fixing roller 18
The heater power is turned on, and the static elimination bar 12A is turned on.
, a transfer power source for the transfer device 12 , a driving power source for the photoreceptor belt 1 and each developing device, and a charging power source for the charger 6 ,
The developing bias voltage power supply and the like for each developing device are put on standby.

The control section of the apparatus is configured to input signals from various detection means arranged at key points to a built-in process sequence memory, and detects a correct position signal of the process cartridge, which will be described later, and detects the paper. If a print signal is input by operating a copy button (not shown) in a state where no signal or jam signal is detected, the power source, drive source, or power transmission of each of the image forming means and related equipment is interrupted. A signal is output to the system to execute the image forming process described above.

The photosensitive drum 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.

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

The housing 70 housing the process cartridge 30 and the laser writing system unit 7 has a guide device 31 or 71 constructed between the back side and the main body of the apparatus.
It is inserted by sliding from the upper right side as shown in FIG.

[0035] Furthermore, the process cartridge 30 includes:
On the drive roller 2 protruding from the back surface and the extension shaft of the developing sleeve of each developing device, a gear G2, a gear G8,
G9, G10, and G11 are each fixed with a step in the axial direction, and at the same time as they are set to the mounting position, each of these gears is connected to the drive gear G2A and gear G on the device main body side.
8A, G9A, G10A, and G11A are meshed all at once.

FIG. 4 shows a cross section taken along arrow AA in FIG.

Each of the guide devices 31 and 71 is formed of a guide member 31A or 71A having a concave wedge-shaped cross section and a guide member 31B or 71B having a convex wedge-shaped cross section, respectively. are fixed to the back side of the process cartridge 30 or the housing 70, respectively, while the guide member 31
Both B and 71B are drive units 20 of the device main body that are inserted through the main body panel 100A on the back side and installed on the outside thereof.
Fixed directly to 0.

Furthermore, the process cartridge 30 and the housing 70
has rotatable rollers 35 and 75 on each front part.
A pair of guide devices 31 and 7 are provided protrudingly from each other.
By being supported by the cradle 36 and 76 on the main body panel 100B installed parallel to the main body panel 100B, the main body panel 100B is housed in the apparatus in a balanced state in the front and rear direction.

In the image forming apparatus of the present invention, the power supply circuit and the control circuit are formed into an electrical component 300 in which the portion indicated by the two-dot chain line in the block diagram shown in FIG. 2 is mounted on a single board and made into a unit. , drive unit 2
00 is installed on the outer surface of the main body panel 100A.

Therefore, the electrical equipment section 300 can be easily assembled by simplifying the wiring, and at the same time, by covering it with a simple cover 300A made of sheet metal, that is, a metal plate, it is electrically shielded and is protected from harmful high-frequency waves. It has the effect of preventing the occurrence and blocking external influences.

On the other hand, the process cartridge 30 has the following features:
At the installation position in the apparatus main body, the magnetic catch type connector 33 provided on the back side is connected to the connector on the electrical equipment section 300 side provided on the apparatus main body side, and each image forming means ( In the block diagram shown in FIG. 2, the operation and control action of the portion indicated by the dashed line is performed.

In order to open the image transfer area of the device, the process cartridge 30 is moved from the position shown in FIG. 1 by the handle 3.
4 in the direction of the arrow, the connector 33 is disconnected from the electrical transmission section 300, and the power supply or control circuit indicated by (crossed) in the block diagram in FIG. 2 is automatically cut off. At the same time, the process power source is turned off in response to a cartridge position signal indicating that the process cartridge 30 has moved from the mounting position.

Therefore, by moving the process cartridge 30, in addition to operating and controlling the image forming means housed therein, the process cartridge 30 automatically cuts off the power supplies for the fixing heater, transfer, and static elimination, as well as the driving power of the main body of the apparatus to perform copying. Since this operation is prohibited, it is possible to safely remove jammed paper, inspect, clean, etc. by opening the top cover 20. Note that this prohibited state continues even after the process cartridge 30 is taken out of the apparatus main body, and when it is correctly returned to the installed position, it is automatically released and returned to the connected state, making it possible to copy again. .

[0044]

[Effects of the Invention] According to the present invention, it is possible to effectively shield the power supply and control section of the device using extremely simple members, and as a result, the occurrence of erroneous operations is prevented and the image forming process is always stable. An image forming apparatus capable of copying high-quality images has now been provided.

[Brief explanation of the drawing]

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

FIG. 2 is a block diagram showing the power supply and control circuit of the device.

FIG. 3 is an explanatory diagram of main parts of the device.

FIG. 4 is a sectional view of essential parts of the device.

[Explanation of symbols]

1...Photoreceptor belt 6
... Charger 7 ... Laser writing system unit 8,
9, 10, 11...Developer 12...Transfer device
12A... Static elimination bar 13... Cleaning device
17A...Transport belt 18...Fixing roller 20...Top lid 3
0...Process cartridge 30A...Toner supply hopper

Claims (1)

[Claims] Claim 1: In an image forming apparatus equipped with a process cartridge having a panel surface and having at least a belt-shaped photoreceptor that can be inserted and removed, a control board of the image forming apparatus and an electrical component of a power supply etc. An image forming apparatus characterized in that the images are concentrated on one panel surface and shielded with a sheet metal.