JPS62239177A - Multicolor electrostatic recorder - Google Patents

Abstract

PURPOSE:To shorten recording time to obtain recorded image of high quality by placing a recording head in the middle position among plural developing devices for individual colors and forming and developing a latent image each time when the feeding direction of a recording paper is inverted. CONSTITUTION:A recording head 5 is placed in the middle position among color developing devices 6-9, and a recording paper 2 is fed out in the direction of an arrow A, and a feed mark formed by the head 5 is developed by the back developing device 6, and the feeding direction of the recording paper is inverted to develop the formed latent image of the first color by the developing device 7. Each time the feeding direction of the recording paper 2 is inverted, the latent image is developed in different colors by developing devices 8 and 9. Thus, the number of times of back and forth transporting operation is reduced to an about half, and the time required for recording is shortened without making a control system complicated, and dirt and damage of recording paper are reduced to obtain recorded image of high quality.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention forms an electrostatic latent image on a recording sheet such as electrostatic recording paper, zinc oxide photosensitive paper, titanium oxide photosensitive paper, etc. The present invention relates to improvements in a multicolor electrostatic recording device that obtains images and other multicolor recorded images by developing with colored developers.

[Conventional technology]

FIG. 4 is a diagram showing a conventional multicolor electrostatic recording device of this type. 1 is an electrostatic recording paper roll, 2 is an electrostatic recording paper, 3 and 4 are drive rollers, 5 is a recording head, and 6 to 9 are developing devices each holding a developer for each color of black, cyan, magenta, and yellow. be.

Multicolor electrostatic recording is performed in the following steps.

First, the electrostatic recording paper 2 wound around the electrostatic recording paper roll 1 is pulled out to the right in the figure by drive rollers 3 and 4. Feed marks for position detection are recorded in black on both ends of the electrostatic recording paper 2 in the width direction. This feed mark is used to prevent positional deviation between the four color images when they are superimposed. That is, by reading the feed mark with optical sensors installed at both ends of the electrostatic recording paper 2 in the width direction, the amount of feed of the electrostatic recording paper 2 is measured, and the deviation in the feeding direction is corrected accordingly. It has become a thing. After the feed mark has been recorded, the drive roller 3.4 is reversed and the electrostatic recording paper 2 is rewound onto the electrostatic recording paper roll 1. Next, the electrostatic recording paper 2 is sent out again by the drive rollers 3 and 4, and an electrostatic latent image of the first color image is formed by the recording head 5.

Next, a first color developer, for example, developer 8, comes into contact with the electrostatic recording paper 2 to develop the first color on the electrostatic latent image portion.

After the development of one entire screen is completed, the electrostatic recording paper 2 is rewound onto the electrostatic recording paper roll 1 by drive rollers 3 and 4.

Furthermore, in the same way, the second color and the third color.

After the fourth color image is formed, the electrostatic recording paper 2 is discharged from the apparatus.

[Problem that the invention seeks to solve]

The multicolor electrostatic recording device having the above configuration has the following problems. In the entire process of multicolor electrostatic recording, the electrostatic recording paper 2 is transported over the recording head 5 four and a half times, that is, nine times. Among the transport operations of the electrostatic recording paper 2, the transport operations for rewinding the electrostatic recording paper 2 four times do not contribute to image formation in any way and are simply transport operations for rewinding the electrostatic recording paper 2. Therefore, the time required for rewinding was wasted. Further, since the electrostatic recording paper 2 is transported back and forth many times, there is a problem in that the image is smudged due to friction with the recording head 5, drive rollers 3, 4, etc. during the transport operation. In addition, if an attempt is made to perform the rewinding operation at a high speed in order to shorten the rewinding time, it is necessary to change not only the direction of rotation of the motor but also the number of revolutions, which poses a problem in that the control system becomes complicated.

Therefore, the present invention has developed a multi-color electrostatic capacitor that can shorten the recording time without complicating the control system, perform quick recording, and obtain high-quality recorded images with less staining of the recorded images. The purpose is to provide a recording device.

[Means for solving problems]

In order to solve the above-mentioned problems and achieve the object, the present invention takes the following measures. That is, in a multi-color electrostatic recording device in which a recording sheet is transported back and forth, and in synchronization with this reciprocation, the recording head repeatedly forms an electrostatic latent image of a specific color and the developing device repeatedly develops a specific color. The recording head is arranged at an intermediate position between a plurality of developing units for each color, and each "during forward transport operation" and "during return transport operation" is performed.
Now, the recording operation is executed respectively.

[Effect]

By taking such measures, the following effects occur. Since the recording operation is performed each time the recording paper is transported "outward" and "backward",
There is no waste in the transfer operation, and recording can be done in a short time. Moreover, since the number of reciprocating operations is about half that of the conventional method, staining of recorded images due to abrasion is significantly reduced. Furthermore, since the speed of the "return transport operation" is not increased, the control system can remain the same as before, and there is no risk of it becoming complicated.

Hereinafter, the present invention will be explained in detail with reference to the conceptual diagram shown in FIG. In FIG. 1, the same parts as in FIG. 4 are given the same reference numerals, and detailed explanations of those parts will be omitted.

As shown in FIG. 1, the recording head 5 has developing units 6 to 9 for each color.
It is placed at an intermediate position between the
Recording operations are performed during the "outward transport action" and the "return transport action poems."

First, the electrostatic recording paper 2 is sent out in the direction of the arrow by drive rollers 3 and 4, and after an electrostatic latent image of a feed mark is formed by a recording head 5, the feed mark is recorded by a black developer 6. Next, the drive roller 3.4 is reversed, and when the electrostatic recording paper 2 is rewound onto the electrostatic recording paper roll 1, an electrostatic latent image of the first color is formed by the recording head 5, and the electrostatic latent image of the first color is Development is performed, for example, by a developing device 7. Next, the drive rollers 3 and 4 are reversed, and in the process of transporting the electrostatic recording paper 2 in the direction of the arrow, the recording head 5 forms an electrostatic latent image and, for example, the developing device 8 develops a second color. It will be done. Thereafter, third and fourth color recorded images are formed in the same manner.

In this way, the recording of the feed mark, the second color, and the fourth color is performed during the transport process in the direction in which the electrostatic recording paper 2 is sent out, and the recording of the first color and the third color is performed on the electrostatic recording paper 2. 2 is carried out during the transport process in the direction in which it is rewound. Therefore, the electrostatic recording paper 2 only needs to be transferred back and forth two and a half times, that is, five times, and the number of transfer operations can be significantly reduced.

〔Example〕

FIG. 2 is a diagram showing a first embodiment in which the present invention is applied to an electrostatic recording type multicolor image recording apparatus. Electrostatic recording paper roll 1
The electrostatic recording paper 2 wound around the electrostatic recording paper 2 is transported by driving rollers 3 and 4 in the sending direction (direction of arrow A) and the rewinding direction (direction of arrow B).

The recording head 5 consists of a so-called multi-stylus type recording head main body 50 and a recording paper pressing roller 51 that also serves as a counter electrode. Forms an electrostatic latent image. Reference numerals 53 and 54 denote optical sensors for detecting feed marks formed at both ends of the electrostatic recording paper 2 in the width direction.

Developing devices 6, 7, 8.9 are each black.

This is a developing device that develops yellow, magenta, and cyan colors. These developing units 6, 7, 8, and 9 have the same structure, and each contains a developer of a corresponding color.

Now, to explain the structure of the developing device 6 as an example, the upper part of the main body 60, which is raised and lowered by a lifting device (not shown), has a
A developing slit 61 and a squeeze slit 62 are provided. The developer slit 61 is connected to a developer tank 65 via a pipe 64 having a liquid feed pump 63 in the middle. In addition, the squeeze slit 62 has a suction pump 66 in the middle.
It is connected to a developer tank 65 via a tube 67 with a . Note that 70 to 77 of developing device 7 and 80 to 8 of developing device 8
7. 90 to 97 of the developing device 9 correspond to 60 to 67 of the developing device 6, respectively.

Next, the operation of the apparatus configured as described above will be explained. First, the electrostatic recording paper 2 is transported in the direction of the arrow. During this transfer process, an electrostatic latent image of the feed mark is formed on both ends of the electrostatic recording paper 2 in the width direction by the recording head 5, and the black developer 6 is activated to develop and record the feed mark. Ru. The subsequent feeding amount of the electrostatic recording paper 2 is determined by the optical sensor 53.
54 is controlled by sensing the feed mark.

Next, the electrostatic recording paper 2 is transported in the direction of arrow B, a yellow electrostatic latent image is formed by the recording head 5, and a yellow image is formed by the yellow developing device 7.

Subsequently, the electrostatic recording paper 2 is transported in the direction of arrow A to form a magenta image, transported in the direction of arrow B to form a cyan image, and finally transported in the direction of arrow A to form a black image to form a completed color image. The image is ejected from the device.

As described above, in this embodiment, each recording operation is performed during the reciprocating movement of the recording paper 2, and there is no wasteful transporting process. Therefore, efficient recording can be performed in a short time. Furthermore, since the number of reciprocations is reduced compared to the conventional method, the occurrence of stains due to friction between the electrostatic recording paper 2 and the recording head 5 etc. can be suppressed as much as possible. Furthermore, since the electrostatic recording paper 2 is transported at a constant speed regardless of whether it is transported in the A direction or the B direction, there is no need to change the rotation speed of the motor, and the control system is not complicated. That's not it.

FIG. 3 is a diagram showing a second embodiment in which the present invention is applied to an image recording apparatus using a photosensitive paper 100 having photoconductivity such as zinc oxide or titanium oxide as the recording paper. The configurations of the recording paper transport system and the developing system are the same as in the first embodiment. In FIG. 3, 100 is photosensitive paper, and 101 and 102 are corona chargers. A corona charger 101 is used when the photosensitive paper 100 is transferred in the direction of arrow A, and a corona charger 102 is used when the photosensitive paper 100 is transferred in the direction of arrow B, so that the photosensitive paper 100 is uniformly charged. There is. 103 is a laser beam generation source, and the laser beam emitted from this laser beam generation source 103 is modulated by a light modulation element 104 according to a signal from a control circuit (not shown). The modulated laser beam is scanned by a polygon mirror 105, and the correction optical system 1
The photosensitive paper 100 is irradiated through 06. The charges on the photosensitive paper 100 irradiated with laser light disappear, and the photosensitive paper 100
A negative electrostatic latent image is formed thereon. The electrostatic latent image on the photosensitive paper 100 is reversely developed by the developing devices 6.7 and 8.degree. 9, and only the portion irradiated with the laser beam becomes an image. The second embodiment is the same as the first embodiment except that the electrostatic latent image is formed by a recording head using laser light, and a color image is formed by the steps described above.

It should be noted that the present invention is not limited to the above embodiments. For example, in the second embodiment, a laser beam is used as the recording head for applying an optical signal to the photosensitive paper, but
A recording head using an LED array, a liquid crystal shutter array, etc. may also be used.

Further, although the second embodiment shows a case in which a modulated optical signal is used as the recording optical image, it is also possible to construct a color copying machine so that the optical image from the original is used directly. be. It goes without saying that various other modifications can be made without departing from the gist of the present invention.

〔Effect of the invention〕

According to the present invention, the recording head is disposed at an intermediate position between a plurality of developing devices for each color, and each "during forward transport operation" and "during forward transport operation" and "
Since the recording operation is executed during each return transport operation, there is no waste in the transport operation, and recording can be performed in a short time. Moreover, since the number of reciprocating operations is about half that of the conventional method, staining of recorded images due to abrasion is significantly reduced. It should be noted that since the speed of the "backward transfer operation" is not increased, the control system may remain the same as before, and there is no risk of complications. In this way, we provide a multicolor electrostatic recording device that can shorten the recording time without complicating the control system, perform rapid recording, and obtain high-quality recorded images with less staining of recorded images. can do.

[Brief explanation of drawings]

FIG. 1 is a conceptual diagram of the present invention, FIG. 2 is a diagram showing a first embodiment of the invention, and FIG. 3 is a diagram showing a second embodiment of the invention. FIG. 4 is a schematic diagram showing a conventional example. DESCRIPTION OF SYMBOLS 1... Electrostatic recording paper roll, 2... Electrostatic recording paper, 3° 4... Drive roller, 5... Recording head, 6-9...
・Developers for each color of black, cyan, magenta, and yellow, 50...Multi-stylus type recording head body,
51... Recording paper pressing roller that also serves as a counter electrode, 52
...Signal circuit, 53.54...Light sensor, 100
...Photosensitive paper, 101,102...Corona charger, 1
03... Laser light generation source, 104... Light modulation element,
105... Polygon mirror, 106... Correction optical system. Applicant's agent Patent attorney Atsushi Tsuboi Figure 1 Figure 2

Claims (1)

[Claims] In a multicolor electrostatic recording device, a recording sheet is transported back and forth, and in synchronization with this reciprocation, a recording head repeatedly forms an electrostatic latent image of a specific color and a developer develops a specific color. A multi-color electrostatic device characterized in that a head is arranged at an intermediate position between a plurality of developing devices for each color, and recording operations are performed during each "outward transport operation" and "return transport operation" respectively. Recording device.