JPH03171165A - Color image forming device - Google Patents

Abstract

PURPOSE:To improve the efficiency in a color image forming action by providing a coloring degree control means which controls the degree of coloring in the order of the color characteristics of a developer when a unit is moved in a direction determined by a direction determining means and the developer is transferred on a transfer sheet via a photosensitive body. CONSTITUTION:The moving directions of the units 2a - 2d are determined by the direction determining means 4 and 5 based on the developer required to express a desired color and the positions of each units 2a - 2d detected by a position detecting means 3. The units 2a - 2d are moved in the directions determined by the direction determining means 4 and 5, by a moving mechanism 6, and the degree of coloring is controlled by the coloring degree control means 4 and 5 in the order of the color characteristics of the developer when the developer is transferred on the transfer sheet via the photosensitive body 1. The degree of coloring is controlled in such a manner that, for instance, the light quantity of an exposing lamp 7, the stop of an optical system 8, a surface potential by a main charger 9, a transfer potential by a transfer charger 10, etc., are adjusted in the order of the color characteristics of the developer. Thus, a color image forming action is efficiently carried out.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a color image forming apparatus, and more particularly, to a color image forming apparatus having a function of forming a single color image extremely efficiently. It is something. [Prior Art] Conventionally, in this type of image forming apparatus, as shown in FIG. 3, for example, a plurality of units 2. ．． 2b, 2, . 2- is deployed. For example, the units 2 and 2- have magenta, cyan, and other colors from above. Developers of different colors are stored vertically downward in the order of yellow and black. Then, each of the units 21 to 2j is integrally moved vertically by the moving mechanism, and each unit 2,
It is designed to transfer each developer in 2J to 2J onto transfer paper to obtain a desired color. [Problems to be Solved by the Invention] However, in the above-mentioned conventional image forming apparatus, for example, when performing full-color copying, the color characteristics of the developer are taken into consideration, and magenta, cyan, etc. Transfer is performed in the order of yellow.
This is because even pale colors with weak tones can be clearly expressed by sequentially transferring the developer from the darkest color onto the transfer paper. Therefore, in the conventional image forming apparatus, each of the units 2. When the units 28 to 2a are moved upward, a 'gA image is possible in this order, and when they are moved downward, the function is merely to switch the positions of the units 28 to 2a. This is a major factor in reducing transfer efficiency when making color copies. SUMMARY OF THE INVENTION Therefore, it is an object of the present invention to make it possible to transfer developer onto a transfer paper in any of the operations of a plurality of units containing developers of different colors, and to perform color image forming operations. An object of the present invention is to provide a color image forming device that can perform the above-mentioned image very efficiently. , developers of different colors are stored in a plurality of units in a developing section arranged opposite to the photoreceptor, and the units are moved integrally by a moving mechanism to transfer each developer in each unit onto a transfer paper. In a color image forming apparatus for obtaining a desired color by transferring, a position detecting means for detecting the position of the unit with respect to the photoreceptor, a developer necessary for expressing the desired color, and the above-mentioned. direction determining means for determining the moving direction of the unit based on the position of the unit detected by the position detecting means; When transferring the developer onto the transfer paper,
This color image forming apparatus is provided with a color development degree control means for controlling the color development degree in accordance with the order of color characteristics of the developer. [Operation] In the color image forming apparatus according to the present invention, the direction determining means determines the above-mentioned position based on the developer required to express the desired color and the position of each unit detected by the position detecting means. The direction of movement of the unit is determined. Then, the unit 7 is moved by the moving mechanism in the direction determined by the direction determining means, and when the developer is transferred onto the transfer paper via the photoreceptor, the color is developed according to the order of the color characteristics of the developer. The degree of color development is controlled by the degree control means. In this case, the degree of color development may be determined by, for example, the light intensity of the exposure lamp. Aperture of the optical system. Surface potential due to main charger. It is controlled by appropriately adjusting the transfer potential etc. by the transfer charger according to the order of the color characteristics of the developer. [Examples] Examples embodying the present invention will be described below with reference to the accompanying drawings to provide an understanding of the present invention. The following example is an example embodying the present invention, and is not intended to limit the technical scope of the present invention. Here, FIG. 1 is one example of the present invention fF! FIG. 2 is a block diagram of the control system of the color image forming apparatus according to the example, and is a flowchart showing the procedure when copying is performed by the color image forming apparatus. As shown in FIGS. 1 and 3, the color image forming apparatus according to this embodiment includes a position sensor 3 (position detecting means), a direction determining means, and a coloring degree controlling means. ．． The position sensor 3 is for detecting the positions of the units 2 to 2a with respect to the photosensitive drum 1 (see FIG. 3), and has a plurality of limits provided corresponding to each unit 2l to 2a. Switch or unit 2I
It is composed of a plurality of reflective photoelectric sensors, etc. that can individually detect 1 to 2j in a non-contact manner. The direction determining means and the color development degree controlling means are realized by a processing program stored in advance in the memory 5 in the control unit 4 that controls the color image forming apparatus. The direction determining means moves the units 28 to 2- based on the developer required to express the desired color and the positions of the units 21 to 2J detected by the position sensor 3. It is used to determine the direction. Further, the coloring degree control means moves the units 21 to 2J in the direction determined by the direction determining means to transfer the developer onto the transfer paper via the photosensitive drum 1. This is to control the degree of color development according to the ranking of color characteristics (tone degree). In the device of this embodiment, the degree of color development is determined by, for example, the light intensity of the n-light lamp 7. Calibration of optical system 8. Surface potential due to 9 during main charge. It is controlled by setting the transfer potential etc. by the transfer charger IO to an appropriate value. Next, based on the HEI, we will clarify the procedure for copying using the color image forming apparatus. In the figure, Sl, S2, . . . indicate each operation step. First, when the copy button is operated in Sl, S2
At this point, a decision is made as to whether to perform a full color copy or a monochrome copy. If it is determined in S2 above that a monochrome copy is to be performed, a monochrome copying operation is performed in S3. That is, for example, the unit 7 containing the blank developer
J (see FIG. 3) is moved and driven by the moving mechanism 6 to a position where the developer can be attached to the surface of the photosensitive drum 1. On the other hand, if it is determined in step S2 that full-color copying is to be performed, in S4, the units 2,
The direction in which 2J should be moved is determined (direction determining means). That is, the developer required to express the desired color and the unit 2 detected by the position sensor 3,
Based on the positions of 2a to 2a, the moving mechanism 6 moves the unit closest to the photosensitive drum 1 among the units containing the required developer to the developing position. ．． If it is determined in step S4 that the unit is to be moved forward to perform copying, then in step S5, the unit 2. 2J are driven to move downward, for example,
Transfer processing is performed for each single color in the order of yellow, cyan, and magenta developers. On the other hand, if it is determined in S4 that the units should be operated backwards to perform copying, the units 2, 2a to 2a
is moved upward by the mobile device tis, and the magenta, cyan, . Transfer processing for each single color is performed sequentially in the order of yellow developer (S6). In steps S5 and S6, when the units 21 to 2- are moved to transfer the developer onto the transfer paper via the photoreceptor drum 1, the IJ developer is transferred in accordance with the order of color characteristics of the IJ developer. The degree of color development is controlled. yellow. When transferring cyan and magenta in this order, the light intensity of the exposure lamp 7 is controlled to increase sequentially. Also, aperture 8. The main charger 9 and the transfer charger 10 are sequentially controlled so that their outputs decrease. On the other hand, magenta and cyan. When transferring in the order of yellow, contrary to the above, the exposure lamp 7 is controlled in the direction of decreasing its light intensity. Also, the above aperture 8. The main charger 9 and the transfer charger 10 are controlled so that their outputs increase sequentially. In this case, as in the case of the conventional device, the sin light lamp 7, the aperture 8. The output control of the main charger 9 and transfer charger 10 may be kept constant. However, when performing transfer in the order of magenta, cyan, and yellow as in the case of the apparatus of this embodiment, the exposure lamp 7
, School 8. 9 during main charge and transfer charge +10
By adjusting the parameters as appropriate, it is possible to obtain images with tones that cannot be obtained with conventional devices. Furthermore, in the image forming apparatus according to this embodiment, the exposure lamp 7. All outputs of the proofreader 8, main charger 9, and transfer charger 10 may be controlled, or may be controlled selectively. When the transfer is performed using the developer closest to the developing section as described above, the moving direction of the units 2 to 2J is changed in S7, and the transfer operation is completed in S8. Transfer processing using developers of other colors is repeatedly performed until a determination is made. As described above, in the color image forming apparatus according to this embodiment, there are a plurality of units 2 containing developers of different colors.
The developer can be transferred onto the transfer paper in any case of 1 to 2 J of reciprocating motion. In this case, if a lighter color developer with a weaker color tone is transferred later than a darker color developer with a stronger color tone, the degree of color development is controlled according to the order of color characteristics of the developer as described above. It is always clearly expressed. As a result, the shape of a color image can be produced extremely efficiently without compromising the tone of each color. Although this embodiment has been explained using an analog type color image forming apparatus as an example, the above-mentioned functions can also be applied to a digital type color image forming apparatus. In this case, in principle, each color is expressed by combining three colors, but it is configured to express colors by slightly shifting the adhesion position of each developer by dithering and overlapping the colors. [Effects of the Invention] As described above, the present invention stores developers of different colors in a plurality of units in a developing section arranged opposite to a photoreceptor, and moves the units integrally by a moving mechanism. In the color image forming apparatus, in which each developer in each unit is transferred onto a transfer paper to obtain a desired color, a position detecting means for detecting the position of the unit with respect to the photoreceptor; a direction determining means for determining a moving direction of the unit based on a developer required to express a desired color and a position of the unit detected by the position detecting means; and a color development degree control means for controlling the color development degree according to the order of color characteristics of the developer when the developer is transferred onto the transfer paper via the photoreceptor by moving the unit in a direction in which the developer is transferred to the transfer paper. Since the color image forming apparatus is characterized in that the developer can be transferred onto the transfer paper in any case where a plurality of units containing developers of different colors are reciprocated. As a result, color images can be created extremely efficiently.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a control i2II system of a color image forming apparatus according to an embodiment of the present invention, FIG. 2 is a flowchart showing the procedure for copying by the color image forming apparatus, and FIG. 3 is a block diagram of the color image forming apparatus according to an embodiment of the present invention. This is a schematic diagram showing the general structure of a color image forming apparatus, and is used to explain the background technology of the color image forming apparatus. [Explanation of symbols] l...Photosensitive drum 2...Developing section 2, to 2a...Unit 3...Position sensor (position detection means) 4...Control unit 5...Memory 6... ...Movement mechanism 7...Exposure lamp 8...Calibration 9...Main charger 10...Transfer chargers S1 to S8...Operation steps

Claims (1)

[Scope of Claims] 1. Developers of different colors are stored in a plurality of units in a developing section disposed opposite to the photoreceptor, and the units are integrally moved by a moving mechanism to A color image forming apparatus that transfers each developer onto a transfer paper to obtain a desired color includes a position detection means for detecting the position of the unit with respect to the photoreceptor, and direction determining means for determining the moving direction of the unit based on the developer to be used and the position of the unit detected by the position detecting means; and a direction determining means for moving the unit in the direction determined by the direction determining means. A color image forming apparatus comprising: a color development degree control means for controlling the color development degree according to the order of color characteristics of the developer when transferring the developer onto the transfer paper via a photoreceptor. .