JP2000056554A - Color electrophotographic image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a color image forming device allowing a process cartridge being used to be used in plural devices by automatically resetting the variety of initial data needed for toner density control, when mounting of the process cartridge that was used in another device is detected. SOLUTION: Data stored in the memory 374 of a process cartridge 390 are compared with data stored in a device main body 14, and if a toner density signal control voltage value and a reference toner density value are equal, the process cartridge is determined to be the one usually used; if they are not equal, the process cartridge is determined to be the one used in another image forming device and initial data are reset.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of forming an electrostatic latent image on an image carrier such as a photosensitive drum, such as a color copying machine or a color printer, and developing the electrostatic latent image to form a recording material. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color electrophotographic image forming apparatus in which a color image is formed by transferring images, the process cartridge including a developing device being detachable.

The above-mentioned process cartridge is a unit in which a charging unit or a cleaning unit, a developing unit, and an electrophotographic photosensitive member are integrally formed into a cartridge, and this cartridge is detachable from an image forming apparatus main body. . In addition, at least one of the charging unit and the cleaning unit, the developing unit and the electrophotographic photosensitive member are integrally formed as a cartridge so that the cartridge can be attached to and detached from the image forming apparatus main body. Further, the developing means and the electrophotographic photosensitive member are integrally formed as a cartridge so that the developing means and the electrophotographic photosensitive member can be detachably attached to the image forming apparatus main body.

Further, the charging means, the developing means, and the electrophotographic photosensitive member, which also serve as a cleaning means, are integrally made into a cartridge, and this cartridge is made detachable from the main body of the image forming apparatus.

[0004]

2. Description of the Related Art In an image forming apparatus for forming an image using a two-component developer composed of a toner and a carrier, toner is replenished by comparing a toner density signal at the time of image formation with a reference toner density. Control is performed to keep the concentration constant. At this time, an electric signal from a sensor for detecting the toner density is used as a toner density signal and a reference toner density signal, and the toner density signal is used as an initial setting value for toner density control at the start of use of an unused cartridge. To determine the control voltage value and the reference toner density value.

[0005]

However, the control voltage value of the toner density signal depends on the toner density detection sensor attached to the developing means in the process cartridge and the hardware of the apparatus main body. When the control voltage of the toner density signal and the reference toner density value are initialized, the process cartridge cannot be used in another image forming apparatus.

Accordingly, it is an object of the present invention to detect in a color electrophotographic image forming apparatus having a process cartridge including a developing means that a process cartridge used in another image forming apparatus is mounted. In this case, by resetting various initial data necessary for controlling the toner density, it is possible to provide a color electrophotographic image forming apparatus in which a process cartridge in use can be used in a plurality of electrophotographic image forming apparatuses. is there.

[0007]

The object is achieved by a color electrophotographic image forming apparatus according to the present invention. In summary, the present invention relates to a color electrophotographic image forming apparatus, a cartridge including a developing device, a unit for detecting that the cartridge has been used in another image forming apparatus, and a toner density at the time of image formation. Means for storing in a cartridge, and means for resetting various initial data necessary for toner density control using the toner density at the time of image formation, wherein the cartridge mounted on the main body is used by another image forming apparatus. If it is detected that the image formation has been performed, various initial data necessary for toner density control are reset using the toner density at the time of image formation stored in the cartridge. is there.

[0008] The typical invention according to the present application is described below with the numbers corresponding to the claims.

According to a first aspect of the present invention, there is provided a color electrophotographic image forming apparatus which detachably attaches a process cartridge and forms an image on a recording medium.
Mounting means for removably mounting a process cartridge having a developing means for developing a latent image formed on the electrophotographic photosensitive drum using toner, and a means for storing various kinds of initially set data; Means for detecting that the cartridge has been used in another electrophotographic image forming apparatus, means for storing the toner density at the time of image formation in the process cartridge, and control of toner density using the toner density at the time of image formation. Means for resetting various necessary initial data, and when it is detected that the process cartridge mounted on the image forming apparatus main body is used by another electrophotographic image forming apparatus, A color electronic device characterized by resetting various initial data required for toner density control using the stored toner density at the time of operation. True image forming apparatus.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A color image forming apparatus according to the present invention will be described below in more detail with reference to the drawings.

(Embodiment 1) FIG. 1 shows Embodiment 1 of the present invention.
1 is a configuration diagram of a color image forming apparatus. This color image forming apparatus includes a color reader section and a color printer section.

[Structure of Color Reader Unit] In FIG.
Platen glass (platen) 3 above the color reader
The document feeder (DF) 30 is disposed on the horizontal side of the document feeder.
2 are installed. There is also a configuration in which a mirror pressure plate (not shown) is mounted in place of the document feeder 302. A light source 303 which is a halogen lamp is provided in the first carriage 314.
304, reflectors 305 and 306 for condensing the light from the light sources 303 and 304 on the original, and a mirror 307 for reflecting the reflected light or the projected light from the original are mounted. Also,
The second carriage 315 is provided with mirrors 308 and 309 for condensing the reflected light from the mirror 307 to the CCD 101 via the lens 310.

The substrate 31 on which the CCD 101 is mounted
1, elements other than the CCD 101 shown in FIG. 2, and the binary conversion unit 201 and video signal counting units 220 and 22 shown in FIG.
1, 222, 223, delay units 202, 203, 204,
And a digital image processing unit 312 including
An interface (I / F) unit 313 with a PU or the like is provided.

The first carriage 314 has a speed V,
The second carriage 315 scans the entire surface of the document (sub-scanning) at a speed V / 2 by mechanically moving the driving unit 316 in a direction perpendicular to the electrical scanning (main scanning) direction of the CCD 101. .

FIG. 2 is a block diagram showing a detailed configuration of the digital image processing unit 312.

In FIG. 1, an original on an original platen glass 301 reflects light from light sources 303 and 304, and the reflected light is guided to a CCD 101 and converted into an electric signal. still,
When the CCD 101 is a color sensor, the RGB color filters may be inline on a one-line CCD in RGB order, or may be a three-line CCD in which an R filter, a G filter, and a B filter are arranged for each CCD. It does not matter whether the filter is on-chip or the filter is configured differently from the CCD.

Then, the electric signal (analog image signal) is input to the image processing unit 312, and the clamp & Am
p. & S / H & A / D unit 102 sample and hold (S
/ H), the dark level of the analog image signal is clamped to the reference potential, amplified to a predetermined amount (the processing order is not limited to the notation order), A / D converted, and, for example, RGB.
It is converted into an 8-bit digital signal.

The RGB signals are output to the shading unit 1.
03, after shading correction and black correction are performed,
In the connection & MTF correction & document detection unit 104, the CCD 10
If 1 is a three-line CCD, the splicing process differs in the reading position between the lines, so the delay amount for each line is adjusted according to the reading speed, and the signal timing is corrected so that the reading positions of the three lines become the same. In the MTF correction, the reading MTF changes depending on the reading speed and the magnification.
The document detection recognizes the size of the document on the platen glass 301.

The digital signal whose read position timing has been corrected is input to the CCD 101 by the input masking unit 105.
And the light sources 303 and 304 and the reflector 305,
The spectral characteristic of 306 is corrected. Input masking unit 105
Is input to the selector 106 which can be switched with a signal passing through the external I / F 114.

The signal output from the selector 106 is subjected to color space compression, background removal & LOG conversion 107 and background removal 1
15 is input. After the signal input to the background removal unit 115 is removed from the background, the signal is input to a black character determination unit 116 that determines whether or not the document is a black character in the document, and a black character signal is generated from the document. Also, another selector 106
The color space compression & background removal & LOG conversion unit 107 to which the output of the above is input determines whether or not the image signal read by the color space compression is within the range that can be reproduced by the printer. In this case, the correction is made so that the image signal falls within a range that can be reproduced by the printer. Then, a background removal process is performed, and the RGB signals are converted into CMY signals by LOG conversion.

Color space compression, background removal, and LOG to correct the signal and timing generated by black character determination unit 116
The output signal of the converter 107 is adjusted in timing by the delay 108. The two types of signals are subjected to moiré removal by the moiré removal unit 109 and then subjected to scaling processing in the scaling unit 110 in the main scanning direction.

UCR & Masking & Black Character Reflection Unit 111
In the signal processed by the scaling processing unit 110, the CMY signal is generated by the UCR process, the CMYK signal is corrected by the masking processing unit to the signal output from the printer, and the black character determination unit 116 generates the signal. The determination signal is fed back to the CMYK signal.

UCR & Masking & Black Character Reflection Unit 111
Is subjected to density adjustment by the γ correction unit 112 and then subjected to smoothing or edge processing by the filter unit 113. The signal processed as described above is supplied to the binary conversion unit 2 shown in FIG.
01 converts an 8-bit multi-level signal into a binary signal.
This conversion method may be any one of the improved dither method, error diffusion method and error diffusion method.

[Arrangement of Color Printer Unit] In FIG. 1, a Y image forming unit 317 for forming a yellow image
An M image forming unit 318 for forming a magenta image, a C image forming unit 319 for forming a cyan image, and a K image forming unit 320 for forming a black image are photosensitive drums 342, 343, 344, and 345, respectively. , Chargers 321, 3
24, 327, 330, LED sections 210, 211, 21
2,213, developing units 322,325,328,331,
Auxiliary chargers 360, 361, 362, 363 are provided. The chargers 321, 324, 327, 330 are
Charging sleeves 370, 371, 372, 373, respectively
And the developing devices 322, 325, 328, and 331 include developing sleeves 355, 356, 357, and 358, respectively.

Since the respective components are the same, the Y image forming section 317 will be described in detail, and the description of the other image forming sections will be omitted.

The Y image forming section 317 includes a photosensitive drum 34
2 around the charger 321 and the LED unit 21.
0, a developing device 322, an auxiliary charging device 360, and the like. Here, as shown in FIG. 10, the photosensitive drum 342, the charger 321 and the developing device 322 form an integrated process cartridge 390.

The process cartridge 390 is detachable from the main body 14 of the image forming apparatus. In this attachment / detachment method, a guide member (not shown) is provided on the image forming apparatus main body 14, and a guide (not shown) provided in the process cartridge 390 is guided by the guide member. The process cartridge 390 has a memory EEP
A ROM 374 is provided.

In these operations, first, the photosensitive drum 342 is charged by the auxiliary charger 360 and the charger 321.
Next, the LED drive 206 (207, 208,
209), a latent image is formed on the surface of the photosensitive drum 342 by the light from the LED unit 210 driven by the developing unit 3
By developing at 22, a toner image is formed.

The developing device 322 includes a developing sleeve 355 for applying a developing bias to develop. As shown in FIG. 1, a transfer charger 323 is disposed below the developing device 322 in the figure with the transfer belt 333 interposed therebetween, and discharges electricity from the rear surface of the transfer belt 333 so that the photosensitive drum 34 is discharged.
2 is transferred to a recording paper or the like on the transfer belt 333.

After the transfer, the toner remaining on the photosensitive drum 342 is once taken into the charger 321 to change its electrostatic characteristics and return it to the photosensitive drum 342 again.
22 collects this and reuses it.

Next, a procedure for forming an image on a recording paper or the like will be described. The recording paper or the like stored in the paper feed cassettes 340 and 341 is supplied onto the transfer belt 333 by the paper feed rollers 336 and 337 one by one by the pickup rollers 338 and 339. The transfer belt 333 is connected to the Y image forming unit 31.
7, a transfer belt roller 348 disposed below the M image forming unit 318, the C image forming unit 319, and the K image forming unit 320.
Is driven in the direction indicated by the arrow.

The recording paper fed to the transfer belt 333 is
The leading edge is detected by the paper leading edge sensor 347. The detection signal of the paper leading edge sensor 347 is sent from the printer unit to the color reader unit, and is used as a sub-scan synchronization signal when a video signal is sent from the color reader unit to the printer unit.

Thereafter, the recording paper or the like is conveyed by the transfer belt 333, and is transferred to the image forming units 317 to 320 in the Y direction.
A toner image is formed on the surface in the order of MCK.

The recording paper or the like that has passed through the K image forming section 320 is separated from the transfer belt 333 after the charge is removed by the charge remover 349 to facilitate separation from the transfer belt 333. Peeling charger 3 adjacent to static eliminator 349
50 is provided to prevent image disturbance due to peeling discharge when recording paper or the like is separated from the transfer belt 333.

The separated recording paper or the like is charged with a pre-fixing charger 35 in order to compensate for toner attraction and prevent image disturbance.
After the toner image is charged at 1 and 352, the toner image is heat-fixed by the fixing device 334, and then discharged to a discharge tray 335. Further, the transfer belt 333 is discharged by the inside / outside discharger 353.

Next, a method of detecting that the process cartridge 390, which is a feature of the present invention, has been used in another apparatus and resetting the control voltage value of the toner density signal will be described in detail.

First, the structure of the developing device 322 in the process cartridge 390 will be described with reference to FIG. The toner supplied from the toner supply port 42 circulates in the direction of the arrow in the drawing by the rotation of the stirring screw 41. When a developing bias is applied, the toner is blown to the photosensitive drum 342 by the rotation of the developing sleeve 355. The toner density detection sensor 40 converts the toner density in the developing device 322 into an electric signal, and this signal is input as a toner density 45 to the CPU in the apparatus main body 14. Further, the toner density signal 45 is variable by a control voltage 44 from the apparatus main body 14. The main body CPU controls the toner density signal 4 during image formation.
5 is detected at a predetermined timing, and the value is written to the EEPROM 374 in the process cartridge 390.

Next, a control voltage value of a toner density signal and an initial setting method of a reference toner density value for an unused process cartridge 390 will be described with reference to the flowchart of FIG. First, in S51, the stirring screw 41
Then, the developing sleeve 355 is rotated for one minute, and the developing bias AC component is applied in S52. Next, in S53, the control voltage is automatically adjusted so that the toner density signal becomes 2.5V ± 0.15V. At S54, the toner density signal is set to 20 ms.
Sampling is performed 10 times at intervals, and the average value is determined as the reference toner density value. In S55, the determined control voltage value and reference toner density value are stored in the E in the process cartridge 390.
EPROM 374 and backup RAM of main unit 14
Write to. Then, in step S56, the rotation of the stirring screw 41 and the developing sleeve 355 is stopped, and in step S57, the developing bias AC component is turned off, and the process ends. Note that these processes are the same for the process cartridges of all colors.

Next, the present invention will be described with reference to the flowchart of FIG. In step S61, the power of the color electrophotographic image forming apparatus is turned on. In S62, the process cartridge 39
0 is attached to the apparatus main body 14 to check whether the process cartridge 390 is not attached.
If there is, a display for prompting the user to attach it is displayed on the operation panel in S64.
If the process cartridges 390 of all colors are mounted, the process cartridge EEPROM 3
The data stored in the memory 74 is checked. Here, if both the toner density signal control voltage value and the reference toner density value are equal to the values stored in the main body, it is determined that the process cartridge 390 has been used before and the process ends. If at least one of the values is different, it is determined that the process cartridge 390 has been used in another image forming apparatus, the initial data is reset in S65, and each data is stored in the process cartridge 390 and the apparatus main body. finish.
The resetting of the initial data is performed according to the flowchart of FIG. First, in step S71, the stirring screw 41 and the developing sleeve 355 are rotated for one minute, and in step S72, a developing bias AC component is applied. Next, in S73, the control voltage is automatically adjusted so that the toner density signal becomes ± 0.15 V of the toner density value during image formation stored in the EEPROM 374 in the process cartridge 390. Then, the control voltage value determined in S74 is stored in the EE in the process cartridge 390.
The data is written to the PROM 374 and the backup RAM of the apparatus main body 14. Then, in step S75, the rotation of the stirring screw 41 and the developing sleeve 355 is stopped, and in step S76, the developing bias AC component is turned off, and the process ends.

(Embodiment 2) FIG. 8 shows an operation unit of a color image forming apparatus according to the present embodiment. A touch panel display 1001 normally displays the number of copies, the selected paper size, the magnification, and the copy density. 1002
Is a reset key and returns the copy mode to the standard mode. A start key 1003 starts a copy operation. A stop key 1004 interrupts the copy operation. A clear key 1005 returns the copy mode to the standard mode. Reference numeral 1006 denotes a numeric keypad for setting the number of copies.

In the comparison between the data stored in the process cartridge 390 and the data stored in the apparatus main body 14 in S63 in the flowchart of FIG. 6, if at least one of the toner density signal control voltage value and the reference toner density value is different, the other It is determined that the process cartridge 390 has been used in the image forming apparatus, and a user setting mode screen shown in FIG. On the user setting mode screen, the key B indicating the resetting of the initial data of the toner density control is blinking, and the resetting is executed by pressing this key. Pressing the cancel key returns to the normal screen.

[0042]

As described above, according to the present invention, in a color image forming apparatus having a process cartridge including a developing means, it is detected that a process cartridge used in another image forming apparatus is mounted. In this case, by resetting various initial data necessary for toner density control, it is possible to provide a color electrophotographic image forming apparatus capable of using a process cartridge in use by a plurality of apparatuses.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a color image forming apparatus according to a first embodiment.

FIG. 2 is a block diagram illustrating a configuration of a digital image processing unit according to the first embodiment.

FIG. 3 is a block diagram illustrating a configuration of an LED driving unit according to the first embodiment.

FIG. 4 is a configuration diagram of a developing device according to the first embodiment.

FIG. 5 is a flowchart illustrating initialization of toner density control according to the first embodiment.

FIG. 6 is a flowchart illustrating control according to the first embodiment.

FIG. 7 is a flowchart illustrating resetting of toner density control initial data according to the first exemplary embodiment.

FIG. 8 illustrates an operation unit according to the second embodiment.

FIG. 9 is a diagram showing a user setting mode screen according to the second embodiment.

FIG. 10 is a schematic vertical sectional view of a process cartridge.

[Explanation of symbols]

 14: Image forming apparatus main body 40: Toner density detection sensor 41: Toner stirring screw 42: Toner supply port 44: Control voltage 45: Toner density signal 101: CCD 102: Clamp & Amp. & S / H & AD section 103 ... Shading section 104 ... Connecting & MTF correction & original detection section 105 ... Input masking section 106 ... Selector 107 ... Color space compression & background removal & LOG conversion section 108 ... Delay 109 ... Moiré removal section 110 ... Resize processing section 111 UCR & Masking & Black Character Reflection Unit 112 γ Correction Unit 113 Filter 114 External I / F 115 Background Removal Unit 116 Black Character Determination Unit 201 Binary Conversion Unit 202-205 Delay Unit 206-209 LED Drive 210 to 213 LED unit 220 to 222 Video signal counting unit 301 Document platen glass 302 Document feeder 303 Light source 304 Light source 305 Reflective umbrella 306 Reflective umbrella 307 Reflective mirror 308 Mirror 309 Mirror 310 ... Lens 311 ... Substrate 312 ... Image processing unit 313 Interface 314 First carriage 315 Second carriage 316 Driving means 317 Y image forming section 318 M image forming section 319 C image forming section 320 K image forming section 321 Charger 322 Developing device 323 (326, 329, 332) transfer charger 324 charger 325 developing unit 327 charger 328 developing unit 330 charger 331 developing unit 333 transfer belt 334 fixing unit 335 discharge tray 336 Paper feed roller 337 Paper feed roller 338 Pickup roller 339 Pickup roller 340 Paper feed cassette 341 Paper feed cassette 342 to 345 Photosensitive drum 347 Paper edge sensor 348 Transfer belt roller 349 Static eliminator 350 Charger 351: Charger before fixing 352: Charger before fixing 53: Inside and outside static eliminator 355-358 ... Developing sleeve 360-363 ... Auxiliary charger 370-373 ... Charging sleeve 374 ... Memory EEPROM 390 ... Process cartridge 1001 ... Touch panel display 1002 ... Reset key 1003 ... Start key 1004 ... Stop key 1005 ... Clear key 1006 ... numeric keypad

Claims (8)

[Claims] 1. A color electrophotographic image forming apparatus which detachably attaches a process cartridge and forms an image on a recording medium, wherein an electrophotographic photosensitive drum and a latent image formed on the electrophotographic photosensitive drum are developed using toner. A mounting means for removably mounting a process cartridge having a developing means and a means for storing various data which has been initially set; and detecting that the process cartridge has been used in another electrophotographic image forming apparatus. Means for storing the toner density at the time of image formation in the process cartridge; and means for resetting various initial data necessary for toner density control using the toner density at the time of image formation. If it is detected that the process cartridge mounted on the apparatus main body has been used in another electrophotographic image forming apparatus, Color electrophotographic image forming apparatus, characterized in that resetting the various initial data necessary for the toner density control using the toner concentration during operation stored Seth cartridge. 2. A method for detecting that the process cartridge has been used in another electrophotographic image forming apparatus, the toner density control initial setting data stored in the process cartridge and the toner density stored in the image forming apparatus main body. 2. The color electrophotographic image forming apparatus according to claim 1, wherein the control initial setting data is compared. 3. The color electrophotographic image forming apparatus according to claim 2, wherein a control voltage value of a toner density signal and a reference toner density are used as the toner density control initial setting data. 4. The color electrophotographic image forming apparatus according to claim 1, wherein the reset initial setting data for toner density control is a control voltage value of a toner density signal. 5. The color electrophotographic image forming apparatus according to claim 1, wherein the means for resetting various initial data necessary for the toner density control is automatically performed when power to the image forming apparatus main body is turned on. apparatus. 6. The color electrophotographic image forming apparatus according to claim 1, wherein means for resetting various initial data necessary for controlling the toner density is performed by an operation panel. 7. The image forming apparatus according to claim 1, wherein a reset operation is displayed on an operation panel of the main body of the image forming apparatus while the means for resetting various initial data necessary for controlling the toner density is being executed. 2. The color electrophotographic image forming apparatus according to 1. 8. The process cartridge according to claim 1, wherein the charging means, which also serves as a cleaning means, the developing means, and the electrophotographic photosensitive drum are integrally formed into a cartridge, and the cartridge is detachably mountable to an image forming apparatus main body. 1
8. The color electrophotographic image forming apparatus according to any one of items 1 to 7.