摘要:
In a transfer method of a colored image, the process speed is initially properly set in accordance with the size of a copy paper sheet to be used. The transfer voltage is then changed in accordance with the process speed. After these processes, a colored toner image formed on a photoconductor is first transferred onto an intermediate transfer medium and then further transferred onto the copy paper sheet.
摘要:
A toner transfer device which transfers toner on a photoconductor to an intermediate transfer belt applied on a plurality of rollers, wherein at least part of the surface of the photoconductor moves in an arc while being pressed against the intermediate transfer belt, the toner transfer device comprising: a pair of transfer rollers disposed along the intermediate transfer belt between two of the rollers in such a manner that the part of the surface of the photoconductor which moves in an arc is positioned between the transfer rollers, at least part of each transfer roller being located outside each of two tangents, one of the tangents touching the photoconductor and one of the two rollers, the other tangent touching the photoconductor and the other roller, thereby allowing a certain length of the intermediate transfer belt between the two transfer rollers to be pressed against the part of the surface of the photoconductor moving in an arc; and a means for applying voltage to the transfer rollers, the voltage polarity being opposite to that of the toner.
摘要:
A copying apparatus having a prescanning function for obtaining density data to adjust copy parameters includes a correction function which eliminates the data obtained from a portion of a predetermined color, from the density data detected on a prescanning process. The density data can be restricted within a predetermined range. The predetermined range can be easily set by the user.
摘要:
A fixing means for an electrophotographic copier includes a first roller and a second roller which are compressed against each other and serve to fix toner images on an image transferring medium passed therebetween. A control means is programmed to operate the rollers such that the heating of the second roller is continued for a predetermined length of time or until the surface temperature of the second roller reaches a certain predetermined temperature level after the surface temperature of the first roller reaches another predetermined temperature level such that the second roller is prevented from cooling down suddenly after the fixing operation is started. In another aspect of the present invention, the size of the image transferring medium passed between the rollers is detected and the heaters for the rollers are controlled accordingly such that temperature variations on the roller surfaces can be reduced and hence the roller lifetimes can be improved.
摘要:
A conventional image forming device having a plurality of image optical scanning recording sections has had a drawback of being incapable of correcting printing positions of the image optical scanning recording sections with high precision by using a small-scale circuit. In the case of an image forming device of the present invention, a variable clock generator 114 having a voltage control oscillator (VCO) 114a is provided therein as reference clock signal generating means of laser control system of each of image optical scanning recording sections (LSU) for cyan, yellow, and magenta. By so doing, during an invalid printing period prior to a valid printing period, frequencies of the reference clock signals of the LSUs for cyan, yellow, and magenta are adjusted in accordance with offsets of printing start positions of these LSUs with respect to that of the LSU for black, so that printing offsets are eliminated. As a result, the printing start positions are made to coincide with each other with high precision even with a small-scale circuit.
摘要:
An ink liquid supply system for an ink jet system printer includes an ink liquid reservoir for containing ink liquid therein, and a compact size plunger pump for supplying the ink liquid to a nozzle. The compact size plunger pump integrally includes three pressure chambers defined by coaxially connected pistons. The pistons are driven to reciprocate by a plunger associated with an electro-magnetic solenoid. The first pressure chamber functions to introduce the ink liquid from the ink liquid reservoir and develop the ink liquid toward the nozzle. The third pressure chamber functions to introduce an ink liquid collected by a beam gutter of the ink jet system printer for returning the ink liquid to the ink liquid reservoir. The second pressure chamber functions as a damper for decelerating the shift movement of the pistons and plunger, thereby reducing the shock which will be created when the plunger is attracted by the electromagnetic solenoid.
摘要:
An image processing apparatus having an image judgement section for judging whether or not a specific pattern image is included in at least a part of the image data input from an image input section, and a central processing unit for controlling the output of an image based on the judgement result by the image judgement section, wherein the image judgement section comprises a plurality of specific pattern image control tables for controlling different specific pattern images, respectively, and every time image data is input from the image data input section, the order of the plurality of specific pattern image control tables is changed over to perform the image judgement.
摘要:
Developing devices are provided adjacent to a light sensitive element. An intermediate transfer drum is provided adjacent to the light sensitive elements. After exposure of the light sensitive element, a first color or third color image is formed on the light sensitive element. On the other hand, after exposure of the light sensitive element, a second color or fourth color image can be formed on the light sensitive element. The first color image is transferred from the transfer unit to the intermediate transfer drum at the first transfer portion, and the second color image is transferred from the transfer unit at the second transfer portion so as to be superimposed on the first color image. Similarly, the third color image is transferred so as to be superimposed on the second image and the fourth color image is transferred so as to be superimposed on the third color image to the intermediate transfer drum. Accordingly, the first to fourth color images are superimposed. Thereby, downsizing of the device and cost reduction are achieved and image formation speed is facilitated.
摘要:
An image data input portion captures one line of data. The captured RGB data is color-converted into image information of a different set of colors, through the image processing portion. The converted data is written at a set up address on an HD. One page of image information is written onto the HD whilst the HD's address is sequentially incremented by 2. When two colors of data need to be retrieved in parallel from the HD, the data of the colors can be alternately written in. A CPU controls tandem recording units Pa, Pb, Pc and Pd so as to perform printing of respective colors, with a time shift one to the next of a period equal to the pitch of photoreceptor recording units.
摘要:
An ink liquid concentration controller is provided in an ink liquid supply system for an ink jet system printer to ensure a stable printing operation. The ink liquid concentration controller functions to maintain the concentration of the ink liquid at a constant value by supplying a volatile dilution to the ink liquid introduced into the ink liquid concentration controller.