JPH02167570A - Color electrostatic recorder - Google Patents

Abstract

PURPOSE:To align overlapped pictures at every color by detecting a changed temperature and humidity by a temperature/humidity detector provided in contact with or in the vicinity of a recording medium, adjusting the temperature amount of a temperature adjuster according to the quantity comparing temperatures and humidities, with the expansion/contraction information of the recording medium. CONSTITUTION:The subject recorder is provided with the temperature/humidity detector 17 which detects the ambient temperature and humidity of an electrostatic recording paper 1 right before it is recorded by a multi-needle electrode recoding head in contact with or in the vicinity of the recording medium; moreover, the temperature adjuster 18 and an expansion/contraction correcting part 19 are provided on the recorder. At this point, a comparing part compares a signal obtained from the temperature/humidity detecting part 17 with a reference signal and judges them, whereby the expansion/contraction quantity in the direction orthogonal to the feeding direction of the electrostatic recording paper 1 is calculated. According to the calculated expansion/contraction quantity temperature is adjusted by operating the temperature adjuster 18. Therefore, the (n-1)th-picture and the nth-picture can be accurately aligned.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a color electrostatic recording apparatus that continuously records images of different colors in an overlapping manner on the same recording medium to obtain a color image.

2. Description of the Related Art A schematic diagram of a conventional color electrostatic recording apparatus is shown in FIG. 51 is an electrostatic recording paper, 52 and 53 are winders and winders for winding and unwinding the electrostatic recording paper 51 in order to make it reciprocate, and 55 is arranged along the path of the electrostatic recording paper 5↓. 54 is a presser roller for maintaining constant contact between the electrostatic recording paper 51 and the multi-needle electrode recording head 55; 56 is a static elimination bar; 57°5;
8.59.60 is a developing device to which developers of different colors are supplied; 61 is a squeeze for recovering used developer; 62.
63 is a pressure roller and a drive roller for gripping and reciprocating the electrostatic recording paper, and 64 is a drive source capable of forward and reverse rotation.

Next, an explanation will be given of the operation suitable for this configuration.

The electrostatic recording paper 51 is conveyed by a drive roller 62 in the direction shown by the arrow. At this time, an electrostatic latent image of a black image is formed within the effective screen of the electrostatic recording paper 51 by the multi-needle electrode recording head 55, and the developing device 57 supplied with black image agent performs electrostatic suction and is visualized. After being imaged, squeeze 6
In step 1, the used developer is collected and fixed. The electrostatic recording paper 51 on which a black image has been recorded is wound up by a winder 53, and after the black image information has been recorded, the driving source 64 is reversed and the electrostatic recording paper 51 is moved in the direction shown by arrow B by the rewinder 52. After rewinding, the second, third, and fourth color images, such as cyan, magenta, and yellow, are superimposed in the same way as the first color method described above.・Magenta/yellow) can be superimposed to produce a color image.

Problems to be Solved by the Invention However, with this configuration, if the atmospheric temperature and humidity change and the electrostatic recording paper expands or contracts after electrostatic development of the nth color, the electrostatic Since the image formed on the recording paper expands and contracts, it is not possible to accurately superimpose the images after the n-th color, resulting in color misregistration.

Therefore, an object of the present invention is to provide a color electrostatic recording device that does not cause color shift.

Means for Solving the Problems In order to achieve this object, the present invention provides a detection means for detecting temperature and humidity in contact with or near a recording medium, and uses information obtained by this detection means to determine the amount of expansion and contraction of the recording medium. The system is equipped with a temperature control means for keeping the temperature constant and records the overlapping.

Effect: With the above-described configuration, the present invention can detect temperature and humidity detection provided in contact with or near the recording medium, even if the recording medium is likely to expand or contract due to a change in ambient temperature and humidity during recording of each color. Detect the temperature and humidity after the change,
This is because the amount of expansion and contraction of the recording medium can be kept constant by comparing the internal temperature and humidity with the expansion and contraction information of the recording medium and adjusting the temperature of the temperature controller according to the comparison amount. , it becomes possible to align the superimposed images for each color.

EXAMPLES Hereinafter, preferred examples of the present invention will be described with reference to FIGS. 1 to 3.

FIG. 1 shows a schematic configuration of a color electrostatic recording apparatus according to an embodiment of the present invention. In FIG. 1, 1 is an electrostatic recording paper, 2 and 3 are winders and winders for winding and unwinding the electrostatic recording paper to make it reciprocate, and 5 is a winder for winding the electrostatic recording paper along the path of the electrostatic recording paper 1. This is a multi-needle electrode recording head arranged in a central location. 4 is a presser roller for maintaining contact between the electrostatic recording paper 1 and the multi-needle electrode recording head 5; 6 is a static elimination bar; , 8, 9, and 10 are developing devices each supplied with developer of a different color. 11 is a squeeze for collecting used developer. ↓ 2 and 13 are for gripping the electrostatic recording paper and making it reciprocate. The pressure roller and the drive roller 14 are drive sources capable of forward and reverse rotation. 17 is a temperature/humidity detector which is provided in contact with or near the electrostatic recording paper and detects the ambient temperature and humidity of the electrostatic recording paper 1 immediately before being recorded by the multi-needle electrode recording head, and 18 is a temperature controller. It is a vessel. 19 is an expansion/contraction correction section.

The electrostatic recording paper I is conveyed in the direction shown by arrow A by a drive roller and a pressure roller 13, and in the meantime, a multi-needle electrode recording head 5 and a developer, for example, a developer 7 supplied with a black developer, are used to optionally carry out the electrostatic recording paper I. black image information is recorded. At this time, as the electrostatic recording paper 1 is transported, it is wound up by the winder 3 and at the same time, the rewinder 2 unwinds it in synchronization with this.

After all the black image information has been recorded, the drive source 14 is reversed, and the electrostatic recording paper 2 is conveyed by the drive roller 13 in the direction shown by arrow B. At this time, contrary to when recording,
At the same time as the rewinder 2 winds up, the winder 3 unwinds. After rewinding the electrostatic recording paper 1 to a predetermined position, recording is performed while being conveyed again in the direction shown by arrow A.
By performing the unwinding operation in the direction indicated by for each color of cyan, magenta, and yellow, images of different colors are successively superimposed to form a color image in which four colors are superimposed.

Hereinafter, the positioning operation when superimposing images of each color will be explained in detail with reference to FIGS. 2 and 3. Before the electrostatic recording paper 1 is conveyed in the direction shown by arrow A in FIG. At step 17, the ambient temperature and humidity of the electrostatic recording paper 1 at this time are detected. A temperature/humidity sensor is used as the temperature/humidity detector 17, and the temperature/humidity detection circuit 2
The output signal from 0 is sent to the comparator circuit 2 of the expansion/contraction correction section 19. The comparison circuit 21 compares the temperature/humidity output signal from the temperature/humidity detection circuit 20 with the temperature/humidity output signal from the reference signal circuit 22, and determines the amount of expansion/contraction of the electrostatic record 1 assumed under the above detection conditions. Determine. The reference signal circuit 22 includes a third
Correlation data between temperature/humidity and the electrostatic recording paper 1 as shown in the figure is memorized. For example, when the atmospheric humidity is 50% and the ambient temperature is 20°C, the amount of expansion and contraction of the electrostatic recording paper 1 is 50% of the atmospheric humidity. The comparison circuit 21 determines that the elongation is about 0.6% based on the ambient temperature of -10°C. Comparison circuit 21
In this case, the temperature correction amount is always determined by comparing with the previous information which has been reversed for a certain arbitrary time period corresponding to the temperature/humidity detection period. Now, for example, the previous information (at the time of the n-1st image recording) has an atmospheric humidity of 50%, the atmospheric humidity is 20°C, and new information (at the time of the nth image recording) an arbitrary time after the previous information.
When the atmospheric humidity is 50% and the atmospheric temperature is 25° C., it is assumed that the amount of expansion and contraction of the electrostatic recording paper 1 changes from an elongation of 0.58% to an elongation of 0.63% with respect to the reference value. . Therefore, it is determined that in order to maintain the elongation of the electrostatic recording paper 1 at 0.58%, the ambient temperature must be set to 20°C. The output from comparison circuit 21 is then sent to temperature adjustment circuit 23. The temperature adjustment circuit 23 is for varying the ambient temperature near the multi-needle electrode head 5, and the temperature adjustment circuit 18 is installed inside a kite roller provided perpendicularly along the conveying direction of the electrostatic recording paper 1, for example. It consists of a heat roller with a built-in rod-shaped heater.

The temperature controller 18 operates based on a signal from the temperature adjustment circuit 21 to vary the temperature of the electrostatic recording paper l and maintain the ambient temperature at 20°C.

As described above, the temperature/humidity detection section 17 for detecting temperature and humidity is provided in contact with or near the electrostatic recording paper 1, and the signal obtained by this detection section and the reference signal are compared and judged by the comparison section. , calculates the amount of expansion and contraction of the electrostatic recording paper 1 in the direction perpendicular to the conveying direction, and adjusts the temperature controller 18 according to the calculated amount.
By operating and adjusting the temperature, the (n-1)th image and the n-th image can be aligned with high accuracy.

As is clear from the explanation in ``Effects of the Invention'', the present invention provides temperature/humidity detection means for detecting temperature and humidity near the multi-needle electrode recording head, and uses the information obtained by this detection means to
It is equipped with a correction means that calculates the amount of expansion and contraction in the direction perpendicular to the conveyance direction of the recording medium and adjusts the temperature accordingly. Even if there is expansion or contraction, the temperature can be adjusted using a temperature controller according to the amount of expansion or contraction to make the amount of expansion or contraction the same, making it easy to superimpose the positions of images with high precision. It has the advantage of being able to realize a simple structure at low cost.

[Brief explanation of the drawing]

FIG. 1 is a schematic perspective view of a Noller electrostatic recording device according to an embodiment of the present invention, and FIG. 2 shows a temperature/humidity detection section, a signal correction section,
FIG. 3 is a block diagram of a humidity adjustment voltage signal generating section, FIG. 3 is a correlation diagram between temperature/humidity and elongation of electrostatic recording paper, and FIG. 4 is a schematic configuration diagram of a conventional Noller electrostatic recording apparatus. 1... Electrostatic recording paper, 2... Winder, 3... Rewinder-14... Presser roller, 5... Multi-needle electrode Record head, 6...
・・Static elimination bar, 7, 8, 9゜10...Developer,
11... Squeeze, 12... Drive roller,
13...Press roller, 14...Drive source, 17...Temperature/humidity detector, 18...Temperature controller, 19... Expansion correction section.

Claims (1)

[Claims] A conveyance means for conveying a recording medium, and a plurality of multi-needle electrode recording heads arranged along a conveyance path of the recording medium so as to sequentially record images of different colors on the recording medium conveyed by the conveyance means. and a developing device; a detection means provided in contact with or near the recording medium to detect temperature and humidity; and a temperature that maintains a constant amount of expansion and contraction of the recording medium based on the information obtained by the detection means. A color electrostatic recording device characterized by comprising: an adjusting means.