JPH03102362A - Electrophotographic image forming device - Google Patents

Abstract

PURPOSE:To prevent a developing unit from being drawn out when a drum cartridge is loaded by meshing the driving gear of the developing unit with a driving gear on a main body side by loading the drum cartridge. CONSTITUTION:The driving gears 803 and 804 are provided in the stirring rollers 614 and 615 of a color developing unit Y and a black developer storing developing device, and the gear 804 is opposed to the driving gear 805 on the main body side. When the drum cartridge K is loaded in a clamshell opening and closing part 700, the unit Y and the black developing device are pressed to be moved, so that clearance is removed and the gear 804 and the gear 805 are meshed with each other. Since the unit Y and the black developer storing developing device can be attached and detached only when the cartridge K is not loaded by doing thus, a photosensitive drum 10 is prevented from being scratched because the unit Y and the developing device come into contact with the drum 10 when they are attached and detached.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of application in the Ca industry] The present invention relates to an electrophotographic image forming apparatus that includes a drum cartridge in which a photosensitive drum is pivotally supported, and a developing unit having a developing device. [Prior Art] 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 is combined into one unit including the developing device. There are two units that can each be explained separately. In addition, the developing device unit may be one in which only the developing device is removable so that the toner replenishment tank or toner replenishment device cannot be attached or removed while attached to the image forming apparatus, or the tank or toner replenishment device may not be installed. There is also a system in which the toner stored in the developer is used, and when the developer is finished, the developer is replaced with a new one and the developer is discarded. If the photoreceptor drum and developing device are made removable in this way, it will be easier to observe every inch of the interior in detail during inspection and cleaning, and each unit can be removed externally independently for inspection and cleaning. This allows you to proceed with your work very efficiently. Furthermore, each unit has a durability limit on the number of times it can be used repeatedly, and measures are taken to replace the entire unit depending on a certain limit, that is, the durability limit. [Lesson 1 that the invention attempts to solve! ! ] As mentioned above, in order to inspect and clean the image forming apparatus and maintain good image quality at all times, important units such as the photoreceptor drum area and the developing device must be independently removable. It can be said that it is more convenient if it is subdivided. However, if the drive gear of the development unit is in mesh with the drive gear of the main body, it is difficult to attach and detach the development unit, and furthermore, when the photoconductor drum is attached, Attaching and detaching the developing unit may cause problems such as scratches on the photoreceptor drum. The present invention eliminates these problems and aims to provide an electrophotographic image forming apparatus in which the developing unit can be smoothly attached and detached, and the drum unit, etc., will not be damaged. [Means for Solving] In order to solve the above problems, the present invention includes a drum cartridge in which a photoreceptor drum is pivotally supported, and a developing unit having a developing device, and the drum cartridge and the developing unit are removable. In the electrophotographic image forming apparatus, the driving gear of the developing unit is opposed to the driving gear of the main body, and when the drum cartridge is installed, the developing unit is pushed, and the driving gear of the developing unit is opposed to the driving gear of the main body. [Operation] In this invention, when the drum cartridge is installed, the developing unit is pushed, and the driving gear of the developing unit meshes with the driving gear of the main body. When this drum cartridge is installed, the attachment and detachment of the developing unit is restricted. On the other hand, when the drum cartridge is not installed, the developing unit drive gear is not engaged with the drive gear on the main body, so the developing unit cannot be installed. It can be easily removed,
Since the drum cartridge is not installed during this attachment/detachment, the 11% light drum will not be damaged as it is pivoted by the drum cartridge. [Example] Hereinafter, an example of the present invention will be described in detail based on the accompanying drawings. 341 and 2 are side sectional views showing the configuration of the talum shell type electrophotographic image forming apparatus of the present invention, and FIG. 1 is also a plan view of this embodiment. It also shows the 1-1 sectional view of Figure J3, and Figure 's4 is a perspective view of the clamshell type electrophotographic image forming apparatus. In the figure, reference numeral 10 denotes a drum-shaped image carrier, that is, a photoreceptor drum, which is driven and rotated clockwise in FIG. 2 and counterclockwise in FIG. A charging electrode 30 is a laser writing system unit which is an exposure optical system, and when a laser writing signal is input to the laser writing system unit 30, the periphery of the photoreceptor drum 10 to which a charge has been previously applied by the charging electrode 20 is It is projected onto the surface. On the other hand, when scanning is started, the laser beam is detected by the index sensor, modulation of the laser beam by the color signal 'M1 is started, and the modulated laser beam scans the circumferential surface of the photoreceptor drum 10. Therefore, a latent image for the first color is formed on the circumferential surface of the photoreceptor drum 10 by the main scanning by the laser beam and the sub-scanning by the rotation of the photoreceptor drum 10. ．． This latent image is number one! For example, the toner image is developed by a developing means containing a yellow developer, and a yellow toner image is formed on the circumferential surface of the photoreceptor drum IO. The obtained toner image, while being held on the circumferential surface of the photoreceptor drum 10, passes under the cleaning means which is separated by the surface of the photoreceptor drum 100, and enters the next copy cycle. The photosensitive drum 10 is charged again by the charging electrode 20, and then the second color signal outputted from the signal processor is inputted to the writing system unit 30, and is photosensitive in the same manner as in the case of the second color signal described above. Writing is performed on the peripheral surface of the body drum 10 using the second color signal to form a latent image. The latent image is "s2"
For example, the color is developed by a developing means containing a magenta developer. 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 photoreceptor drum 10, passes under the cleaning means which is separated from the same surface of the photoreceptor drum 10, 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 as a 3@3 color by a developing means containing a cyan developer, for example. This cyan toner image is formed superimposed on the yellow and magenta toner images described above. A color toner image is formed on the photoreceptor drum 10 using the above three color toners, and a high-quality color image can be obtained by further overlapping a black toner image in the same manner. 611A, 811B, 611C. Reference numeral 6110 denotes a developing device containing yellow, magenta, cyan, and black developers for performing the above-mentioned development, which are arranged one over the other in the circumferential direction of the photosensitive drum 10. As shown in the example of the developing device 611A, each of the developing devices includes a developing roller 812 having a magnetic pole fixed at a position opposite to the circumferential surface of the photoreceptor drum 10 at a predetermined distance, and a developing roller 812 having a magnetic pole fixed at a position facing the circumferential surface of the photoreceptor drum 10 at a predetermined distance. It is equipped with a pair of stirring rollers 614 and 615 that have a conveying force,
By the mixing action of the stirring rollers 614 and 615, the developer is supplied to the circumferential surface of the rotating developing roller 612 after the ratio of toner and carrier is equalized. Direct current or even alternating current bias is applied to the developing roller of each developing device carrying developer, so that non-contact reversal development is performed using the two-component developer. Exposure and development by the photosensitive drum 1o, the charging electrode 2o provided at the peripheral edge thereof, and the laser writing system unit 3o for each color and the developing devices 611A, 61
18.611C 611D is performed four times for each color, so that the photoreceptor drum io
Color toner images are formed on the circumferential surface of the toner image by superimposing them. Reference numerals 61 and 62 designate a first paper feed roller and a second paper feed roller that are in constant rotation, and 71 and 72 designate paper feed guides that are cylindrical and linear, respectively. This recording paper is fed along the paper feed guide 71 by the 's1 paper feed roller 6l, and after being turned U-turn, that is, upside down, the paper is sent to the paper feed guide 71.
It comes into contact with the rising edge of the paper feed shutter S that cuts off the conveyance path of the sheet and stops temporarily. In this case, the second paper feed roller 62 continues to rotate by slipping the stopped recording paper over its surface. When the paper feed shutter S retreats downward in synchronization with the rotation of the photoreceptor drum 10 carrying the toner image, the recording paper is moved onto the photoreceptor drum 1 by the frictional force of the second paper feed roller 62.
It is fed to the transfer section T in synchronization with a circumferential speed of 0.

Reference numeral 80 denotes a rotatable transfer roller, which is electrically charged by applying a voltage, and transfers a toner image to a recording paper side through a transfer belt 80B at the point of contact with the circumferential surface of the photoreceptor drum 10. A transfer belt 80B is stretched between the transfer roller 80 and the drive roller 80A, which constitute the transfer roller 80A, and the recording paper is transferred while being conveyed by the transfer belt 80Be. Note that 80C is a cleaning means for cleaning the surface of the transfer belt 80B. 90 is front V
i! The cleaning device ioo is located upstream of the cleaning device ioo, and is placed in a state where it is easy to remove the residual toner on the circumferential surface of the photosensitive drum 10 that has transferred the toner image onto the recording paper. 100 is a cleaning device; 110 and 120 are conductive collection rollers which are cleaning means of the cleaning device 100; and 13
Reference numeral 0 denotes a toner collecting section that stores the toner collected by the cleaning means, and is built in a drum cartridge K in which the photosensitive drum 10 is supported pivotally. In the transfer section, the recording paper that has received the toner image is
It is separated from the circumferential surface of the photoreceptor drum 100 and is rapidly transported to the fixing device 60. Reference numeral 63 denotes a pair of heat rollers for fixing, and numeral 64 denotes a pair of paper ejection 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 60 by the pair of paper ejection rollers 64. 73 and 74 are paper ejection guides for guiding the recording paper ejected by the paper ejection roller pair 64 to the upper part of the apparatus main body, and the recording paper is guided by the paper ejection conveyance rollers 65 and 66.
And with the image plane facing downward by relay 67,
The sheets are discharged and stacked on the tray 75. The developer replenisher 200 stores yellow toner in a frame 701 of a toothpick clamshell opening/closing portion 700 shown in FIGS. 2 and 3. Magenta. cyan. Tanks 201A, 201B, 201C, 20 are containers of the same diameter for each color of black.
1D are arranged in parallel in one row. Then, the gears 205A, 206, 207, 2 are driven by the drive starter 205.
Each of the tanks 201A, 201B, 20 via 08A
1C. The stirring shaft 201D and the spiral shaft 208 are rotatable, and flexible spiral members 271 connected to the spiral shaft 208 are provided in the hoses 272A to 272D, and these serve as independent conveying means for replenishing the developer. is in charge. Sviral axis 208
Due to the rotation, rotation is freely transmitted to the spiral member 271 in the rotational direction of the shaft, and the toner is transported to the distribution container 251 for each color developer of the developer replenishing device 250. Each of the Y, M, and C developing units is a single unit frame 60.
2 to form a color developing unit Y.
Guide rail 713A. The entrance/exit window 7 provided in the frame 701 of the talum shell opening/closing part 700 that is guided by 713B and provided on the upper part of the base part 800 of the image forming apparatus 1
It is designed to be removable from 13 onwards. On the other hand, the black developer storage developing device 611p has a guide rail 713C.
It is set so that it can be independently attached and detached from the entrance/exit window 713 along the opening/closing section 700. Since the configuration of each of the four developing units is the same, the configuration of 611A will be explained. Inside the developer container 603 are the aforementioned developing roller 612 and stirring rollers 614, 61.
5 is accommodated, and the developing roller 612 has rollers 6 at both ends thereof.
An outer diameter portion 613 that is a certain amount larger than the outer diameter of No. 12 is also provided. Further, on the right side of the container 603, a gear train 630 for connecting drive transmission to each of the rollers is provided.
There is a toner receiving port on the left side of 03. Mo,
A spring 617 and a guide bin 6 are attached along a rail 819 provided in the container 603 so as to close the receiving opening 621.
A mouth opening/closing member 618 is provided which is biased by 16. Then, the container is moved to the developing device 6 by a spring 625.
1 1A are outer diameter portions 613 at both ends of the developing roller 612, which are brought into pressure contact with the drawing of the photoreceptor IO. Than this,
The gap between the developing roller 612 and the photoreceptor drum 1O is designed to maintain an optimum gap for forming a magnetic brush. On the other hand, the frame 701 of the talum shell opening/closing part 700 is
Bearing section 80 provided in frame 801 of base section 800
The opening/closing operation is enabled by the rotating support shaft 702 that fits into the opening/closing operation. When the talum shell opening/closing part 700 is opened in this way, Y, M. Developing unit Y consisting of three color developing units C is located at entrance/exit window 7 of the talum shell opening/closing i'yoo.
13 to the guide rails 713A and 713B, allowing for easy attachment and detachment. Further, the developing device 611D for black toner can be easily attached and detached as a single unit by being guided by the guide rail 713c of the entrance/exit window 713 of the frame 701 of the clamshell opening/closing section 700. Color developing unit Y and black developer storage developing device stto
The stirring rollers 614 and 615 are equipped with a drive gear 803.
, 804 are provided, and this drive gear 804 faces the drive gear 805 on the main body side. Drive gear 805 on the main body side
is connected to a motor (not shown), and when the drum cartridge K is not attached to the tarram shell opening/closing part 700, the drive gear 804 of the stirring roller 615 is connected to the drive gear on the main body side, as shown by the dotted line in FIG. A predetermined clearance L is set to prevent meshing with 8o5. Drum cartridge K is Talam Shell Kaishiro 700
When the drum cartridge K is installed, the developing unit Y and the black developer storage developing device 611D are pushed and the clearance L is eliminated, and the drive gear 804 provided on the stirring roller 615 is moved to the drive gear on the main body side. 805, and when the drum cartridge K is attached or detached, the drive gear 8 of the developing unit Y and the black developer storage developing device 611D is automatically activated.
04 and the drive gear 805 on the main body side are intermittent. In this way, when the drum cartridge K is installed, the developing unit Y and the black developer storage developing device 611D
The W! The A moving gear 804 meshes with the driving gear 805 on the main body side, and this restricts the pulling out of the developing unit Y and the black developer storage developing device 611D, and the developing unit is attached to the photoreceptor drum 10 that is pivotally supported by the drum cartridge K. It will not cause any damage if it comes into contact with Y or black developer storage developing unit 611Df1K. In addition, when the drum cartridge K is not installed, the developing unit Y and the black developer storage developing device 61
Since the 1D drive gear 804 and the drive gear 805 on the main body side are disengaged, the developing unit Y and the black developer containing developing device 611D can be pulled out smoothly. Further, the legs 503 and 504 of the drum cartridge K are provided to facilitate inspection, cleaning, etc. when the drum cartridge K is pulled out from the clamshell opening/closing part 700 and placed on an arbitrary table, making it easy to handle. In this way, since the drum cartridge K, the developing unit Y, etc. are installed and removed while the clam shell opening/closing section 700 is open, maintenance inspection becomes easy and replacement with a new one becomes easy. ．． Further, by attaching and detaching the drum cartridge K containing the photosensitive drum 10 and the developing unit Y so as to be perpendicular to each other, loading assembly and operation are safer and more reliable than parallel loading. Effects of the Invention As described above, in this invention, when the drum cartridge is installed, the developing unit is pushed and the driving gear of the developing unit meshes with the driving gear on the main body side. The drive gear of the developing unit meshes with the drive gear of the main body to restrict the removal of the developing unit.
It can be installed and removed without the drum cartridge being installed. Therefore, the developing unit can be easily attached and detached without damaging the photosensitive drum of the drum cartridge.

[Brief explanation of drawings]

1 and 2 are side sectional views showing the structure of a talum shell type electrophotographic image forming apparatus of the present invention, and FIG. 1 is also a 1-1 cross section of FIG. 3, which is a plan view of this embodiment. FIG. 4 is a perspective view of a talam shell type electrophotographic image forming apparatus. In the drawing, reference numeral 10 is a photosensitive drum, 614, 615 are stirring rollers, 803, 804, 805 are drive gears, K is a drum cartridge, Y is a developing unit, and L is a clearance. Patent Applicant Konica Co., Ltd. Procedural Amendment Case Indication 1999 Patent [II'S241402 Name of the Invention Relationship with the Electrophotographic Image Forming Device Amendment Case Patent Applicant Address 1 Nishi-Shinjuku, Shinjuku-ku, Tokyo Chome 26-2 Name (1
27) Konica Corporation

Claims (1)

[Claims] In an electrophotographic image forming apparatus that includes a drum cartridge in which a photoreceptor drum is pivotally supported and a developing unit having a developing device, the drum cartridge and the developing unit are removable. The electrophotographic image forming apparatus is opposed to a drive gear of the drum cartridge, and when the drum cartridge is installed, the development unit is pushed and the drive gear of the development unit meshes with the drive gear of the main body. .