JP2002040748A - Color image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a color image forming device capable of recycling recovered toner, and also, capable of forming an image close to the normal image. SOLUTION: The device is provided with a developing means constituted of a cyan developing unit, a magenta developing unit, an yellow developing unit, a black developing unit, a recycling hopper and a recycling developing unit, a cleaning means, a recycled toner replenishing means for replenishing the toner recovered from the cleaning means to the recycling hopper, and a black toner replenishing means for replenishing black toner to the recycling hopper. Each color duty cycle of an original is stored in a memory, the hue is predicted from the duty cycle stored in the memory after plural toner images are formed, and then, the quantity of the black toner to be replenished to the recycling hopper is adjusted in accordance with the hue.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a copier, a laser printer, a facsimile, and the like, and more particularly to a color image forming apparatus using an electrophotographic technique.

[0002]

2. Description of the Related Art A technique for recycling waste toner in a conventional color copying machine is disclosed in Japanese Patent Application Laid-Open Nos. 5-165380 and 62-163804.
There is a technique of recycling black toner and discarding other color toners, and a technique of collecting collected toner of each color in each developing device as described in JP-A-62-9383. In addition, as described in Japanese Patent Application Laid-Open No. 54-113340, there is a technique in which a red toner having a small ratio is collected together with a black toner in a red / black two-color machine.

[0003]

However, according to such a conventional method, according to the techniques described in the above-mentioned JP-A-5-165380 and JP-A-62-163084, waste toner other than black is used. Occurs, and the
In the technique described in Japanese Patent Application Laid-Open No. 9-38383, in consideration of the deterioration of the performance of the recycled toner and the like, if it is used again as a color toner, a problem such as remarkable deterioration of image quality occurs.
Further, the technique described in Japanese Patent Application Laid-Open No. 54-113340 only requires that a small amount of red toner be mixed, but in the case of a color copying machine, cyan, magenta and yellow toners are collected, and the amount of these collected is black. If the number is too large, normal black output becomes impossible.

By the way, the use of a copying machine does not always require only a clear image output. Sometimes, it is sufficient to read the image, for example, to output only for confirming a sentence or to inform a message in the department. Can also be seen. In such a case, it is not necessary to use a new black toner, and even if the image density is low, there is a case where there is no problem.

[0005]

SUMMARY OF THE INVENTION Accordingly, the present invention provides a cyan developing device, a magenta developing device,
A developing unit including a yellow developing unit, a black developing unit, and a recycling hopper and a recycling developing unit; a cleaning unit; a recycled toner replenishing unit that replenishes the toner collected from the cleaning unit to the recycling hopper; Black toner replenishing means for replenishing the toner, storing the duties of each color of the original in a memory, predicting the color of the recovered toner from the duties stored in the memory after forming a plurality of images, and according to the color. A color image forming apparatus characterized in that the amount of black toner supplied to the recycling hopper is adjusted.

[0006]

With the provision of a recycle developing device for recycling waste toner including color toner, the color of the original is predicted, and black toner is replenished to the collected toner, so that the collected toner can obtain an image quality similar to that of black toner. Can be.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A color image forming apparatus 1 employing an embodiment of the present invention will be described with reference to FIG. The color image forming apparatus 1 includes a scanner unit 2, an image processing unit 3, an LSU 4, an image forming unit 5, a sheet feeding and conveying unit 6, a fixing unit 7, a DF unit 8, and the like.

The scanner section 2 sends light reflected on a document to a CCD image sensor 21 through an RGB filter and converts the light into an electric signal.

The image processing section 3 is a section for processing a signal from the CCD image sensor 21 into image data subjected to A / D conversion, shading correction, color tone correction and other image processing.

The LSU 4 converts the image data of the image processing 3 into a laser beam and irradiates the laser beam on the photosensitive drum 51.

The image forming section 5 includes a photosensitive drum 51,
It comprises a main charging section 52, a developing section 53, a transfer belt 54, a cleaning section 55, a recycled toner replenishing means 56, and a discharging lamp 57.
1. It has five developing units: a magenta developing unit 532, a yellow developing unit 533, a black developing unit 534, and a recycle developing unit 535. The main charger 52 is provided in a shield case opened toward the photosensitive drum 51 in a range of 50-10.
A thin tungsten wire of 0 μm is stretched in the longitudinal direction of the photoconductor drum 51, and a high voltage of about +5 KV is applied thereto to positively charge the photoconductor drum 51. When the LSU 4 irradiates the charged surface of the photosensitive drum 51 with a laser beam corresponding to image information, an electrostatic latent image is formed on the surface of the photosensitive drum 51. The developing means 53 is applied to the portion of the photosensitive drum 51 irradiated with the laser.
The toner image is formed by the bias voltage of the developing roller and the potential of the surface of the photosensitive drum acting on the positively charged toner agitated in the inside, and the toner image is transferred to the surface of the transfer belt 54. The untransferred toner on the photosensitive drum 51 is scraped off by the rubber blade 551 of the cleaning means 55 in the next process, and the charge is removed by the charge removing lamp 57 so as to reduce the residual potential on the surface and make it uniform. Prepares for the next set of processes. In the case of color output, this operation is performed for each color cyan, magenta, yellow, and black, and is superimposed on the transfer belt 54,
This toner image is transferred onto a sheet at a secondary transfer section (541a, 541b). In the case of a black output, the cyan developing unit 53 is used.
1. The magenta developing unit 532 and the yellow developing unit 533 do not operate, and are performed only by the black developing unit. When requested, the output is performed only by the recycle developing unit.

The paper feeding and conveying means 6 includes a paper feeding cassette (61).
1, 612), a paper feed roller (621, 622), a vertical conveyance path 63, a pair of registration rollers (64a, 64b), and a conveyance belt 64. The paper cassette (61)
1, 612), there is a sheet stacking plate on which a plurality of sheets are stacked, and the sheet stacking plate is a spring or a top motor of the sheets stacked by a lift motor or the like is the sheet feed roller (621). , 622). The registration roller pair (64a, 64b) stops the sheet once to adjust the timing of transferring the toner image of the photosensitive drum 51 of the image forming unit 5 to the conveyed sheet and to adjust the leading end of the sheet. Has a role of transporting the paper from the printer to the image forming means 5. The transport belt 65 transports the sheet on which the unfixed toner has been transferred to the fixing unit 7. The necessary number of the transport rollers in each transport path are laid out as needed.

The fixing means 7 includes a first heat roller 71, a first heater 711 therein, and a second heat roller 72.
The inside second heater 721 and the fixing discharge roller pair (7
3a, 73b) and the like. The heat roller pair (71, 72) is made of aluminum or the like having good thermal conductivity and coated with fluorine, and the two heaters (711, 72) are used.
By incorporating 1), the temperature is controlled to a predetermined temperature required for fixing. The first heat roller 71 is opposed to the second heat roller 72 at an appropriate pressure, and is driven by driving means (not shown). The heat roller pair (71, 72) has a base made of an aluminum roller having good heat conductivity, and its periphery is covered with an elastic layer in order to secure a fixing nip width. Although not shown, each roller is provided with a claw member for peeling off the sheet, and a roller or web for cleaning.

The operation of the color image forming apparatus will be described with reference to FIG. First, the sheet stacking plate (611, 611)
612) is fed to the paper feed roller (62).
1, 622), and is fed to the vertical transport path 63, where it is temporarily stopped by the pair of registration rollers (64a, 64b), and at a predetermined timing, the secondary transfer means ( 541a, 541b), and the unfixed toner is transferred to the upper surface of the sheet in the drawing. The sheet having the unfixed toner transferred to the upper surface is sent to the fixing unit 7 via the transport belt 65. Here, the toner image is fixed on the sheet by being nipped and heated by the nip formed by the heat roller pair (71, 72).
Thereafter, the sheet is discharged to the discharge tray (not shown).

Next, the case where the collected toner is used will be described. The toner collected by the above-described cleaning unit 55 is sent to the recycling hopper 536 by the recycled toner replenishing unit 56. The recovered recycled toner is a mixture of cyan, magenta, yellow, and black toners. If cyan, magenta, and yellow are uniformly mixed, the color becomes close to black and does not cause much problem. Development with the toner is not preferable because the color of the image is clearly different from black. Therefore, in the present invention, for example, 1
When 2,000 sheets of images are formed, the toner that can form an image is collected in the recycle developing device.
At the stage of forming a sheet image, the color of the collected toner is predicted from the data. If the ratio of black is small, black toner is supplied from the black developing device to the black toner replenishing means 53.
Replenish with 7. Thereafter, for example, the tint is predicted from the data in the memory every 200 sheets, and if the ratio of black is small, black toner is supplied. The ratio of black toner is (cyan + magenta + yellow): black = 1:
It is preferable to set it to 1 or more. At least at this rate, it can roughly serve as black. In this embodiment, one-component development is used. However, in the case of two-component development, it is necessary to provide a toner density sensor in the developing device and control the amount of recycled toner supplied to the recycling hopper 536. In this embodiment, the black toner is supplied to the recycle hopper 536 from the black developing device. However, a black toner supply unit may be provided separately.

When the present invention is used, it is preferable that the user selects whether or not to form an image regardless of the image quality. When the recycled toner is used, the setting conditions of each process may be set to the exclusive setting conditions for the recycled toner.

[0017]

As described above, according to the present invention, the recovered toner can be effectively used in spite of being a color image forming apparatus, so that an environmentally friendly color image forming apparatus can be provided.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of a color image forming apparatus employing the present invention.

[Explanation of symbols]

 Reference Signs List 1: color image forming apparatus main body 2: scanner unit 3: image processing unit 4: LSU (laser scan unit) 5; image forming unit 531; cyan developing unit 532; magenta developing unit 533; yellow developing unit 534; Recycle developing unit 536; recycle hopper 537; black toner replenishment means 54; transfer belt 55; cleaning means 56; recycle toner replenishment means 6; paper feeding and transporting means 7; fixing means 8;

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G03G 15/08 507 G03G 15/08 507D 21/10 21/00 326 (72) Inventor Hiroyuki Tsuji Osaka, Osaka Kyocera Mita Co., Ltd. F-term (reference) 2H027 DB01 DD05 DE07 EA06 EB04 ED10 2H030 AD03 AD13 AD16 BB02 BB36 BB38 2H034 AA06 BA00 CB00 2H077 AA37 DA08 DA57 DA78 DB02 GA13

Claims (1)

[Claims] A developing device comprising a cyan developing device, a magenta developing device, a yellow developing device, a black developing device, a recycling hopper and a recycling developing device, a cleaning device, and a toner recovered from the cleaning device. And a black toner replenishing unit for replenishing the recycle hopper with black toner. The duties of each color of the original are stored in the memory, and are collected from the duties stored in the memory after forming a plurality of images. A color image forming apparatus that predicts the color of a toner and adjusts the amount of black toner supplied to a recycling hopper according to the color.