JPS6218577A - Electrostatic recording device - Google Patents

Abstract

PURPOSE:To completely suppress picture omission and to obtain a sharp output picture without the soil of a picture background by making always toner on a magnetic roller surface vertical at the vicinity of a recording electrode pointer irrespective of the magnetic pole position of the magnetic roller. CONSTITUTION:Some part of a molding member 22 made of glass epoxy resin, etc. which fix the recording electrode pointer 2 is mechanically cut off, and thereon a magnetic member 23 is fitted. When the material of the magnetic member is made of pure iron and the inter-edge distance (l) between the recording electrode pointer and the magnetic member and the width l' of the magnetic member are 0.3mm and 5mm, respectively, the behavior of the toner on a sleeve is observed. Then the toner 6a stands almost vertically without fail at the vicinity of the recording electrode pointer, irrespective of the positions of the magnetic poles N and S of the magnetic roller.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an image recording device used in facsimiles, printers, etc., and in particular, recording electrodes and magnetic toner developing devices are arranged through an insulating recording material, and image signals are The present invention relates to an electrostatic recording device in which a magnetic material is attached to a recording electrode of the recording device that simultaneously forms a toner image on an insulating recording medium upon application of a toner image.

[Conventional technology]

The details of the recording principle and configuration of a conventional recording device were previously proposed by the present inventors and a patent application was filed.
The outline of this recording device will be explained once again.

FIG. 5 shows the configuration of the recording section, in which the recording electrode 1
constitutes a multi-stylus in which a plurality of groups of electrode needles 2 are arranged in a row. An insulating recording body 3 made of a dielectric film is brought into contact with this recording electrode l. On the other hand, a magnetic toner developing device 6 having a rotating magnetic roller 5 is installed inside the fixed cylindrical sleeve 4 at a position facing the recording electrode 1 with the insulating recording body 3 interposed therebetween. Further, on the cylindrical sleeve 4, a counter electrode 7 divided into a plurality of segments is arranged in close contact with each other.

When recording, magnetic toner is transferred to the outer circumference of the cylindrical sleeve 4, a voltage corresponding to the image signal is applied to the electrode needle 2, and a voltage of opposite polarity is selectively applied to the counter electrode 7. As a result, magnetic toner is attached to the insulating recording medium 3 to form a toner image.

FIG. 6 shows an enlarged view of how magnetic toner is attached to the insulating recording medium 3 and a toner image 19 is formed in a state where a voltage is applied to the electrode needle 2. Code 2 in the diagram
, 3, 4, 5.7 correspond to FIG. When voltage pulses of opposite polarity are applied to the electrode needle 2 and the counter electrode 7 while the insulating recording body 3 is moving, for example, in the direction of the arrow shown in the figure, the minute voltage between the electrode needle 2 and the insulating recording body 3 is applied. Aerial discharge occurs in the gap, and a latent image charge 20 is formed on the surface of the insulating recording body 3 on the electrode needle 2 side. At the same time, charges of opposite polarity are injected into the toner at the tip of the magnetic brush 18 that has been carried onto the selected segment, attracting the Coulomb force of the latent image charge 20 and forming a toner image 19 on the insulating recording medium 3.
is formed.

Incidentally, an uneven layer having a predetermined height is formed on the surface of the insulating recording body 3 on the side of the electrode needle 2 in order to maintain the micro-gaps necessary for generating an air discharge.

FIG. 7 shows the overall configuration of the recording apparatus, and the symbols 1, 3.4, and 6.7 in the figure correspond to those in FIG. The insulating recording material 3 is made of a dielectric film in the form of a belt, and rollers 8 and 9 are used.
．． 10 to rotate at a constant speed. The tip of the recording electrode 1 is placed in contact with the inside of the insulating recording body 3. Further, a magnetic toner developing device 6 having a counter electrode 7 on the surface of the cylindrical sleeve 4 is installed facing the recording electrode 1. After forming a toner image on the insulating recording medium 3 as explained with reference to FIGS. 6 and 7, the insulating recording medium 3 is rotated to insulate the recording paper 12 at the grounded roller 9. The toner image is transferred to the recording paper 12 from the back side using the transfer roller 13. Thereafter, the transferred image on the recording paper 12 is fixed to the recording paper 12 by a fixing device 14. On the other hand, the insulating recording body 3 is further rotated, and at the portion where the corona static eliminators 16 and 17 are arranged facing each other on both sides of the insulating recording body 3, alternating voltages having different phases are applied to the respective corona static eliminators. When this is added, the charge of the magnetic toner remaining on the insulating recording medium 3 is erased, and the force with which the magnetic toner adheres to the insulating recording medium 3 is weakened. When the insulating recording medium 3 is further conveyed to the rotating pattern recording section, the remaining magnetic toner is collected by the magnetic force of the magnetic roller 5 in the magnetic toner developing device 6.

As described above, the recording process is repeated to output an image, and since such a recording device performs the latent image forming process using the recording electrode and the developing process using the developing machine at the same time, it is difficult to use an output device such as a facsimile. This has the advantage of simplifying the device configuration, making it smaller and cheaper. Furthermore, since magnetic toner is used, untransferred toner can be collected in a developing machine and reused without cleaning, which has the advantage of easy maintenance and low consumables prices.

[Problem that the invention seeks to solve]

Now, in the optical recording method, the magnetic roller 5 of the toner developing device 6
The magnetic toner is transported only by the rotation of the . FIG. 8 is a model diagram of an optical recording type image forming section. Figure 8 (
al indicates a state in which the magnetic poles of the recording electrode 1 and the magnetic roller 5 are exactly opposed to each other. In this state, the toner stands upright on the cylindrical sleeve 4 of the developing machine, and its tip contacts the insulating recording medium 3. , stable image recording is possible. but,
As the magnetic roller further rotates as shown in FIG. 8(b), when the recording electrode and the magnetic poles of the magnetic roller face each other, the toner does not stand upright but lies on the cylindrical sleeve 4 as shown. There is a problem in that the leading edge of the toner does not make sufficient contact with the insulating recording medium, and in the worst case, image loss occurs in this state.

SUMMARY OF THE INVENTION An object of the present invention is to provide an electrostatic recording device that outputs high-quality images without image deletion.

[Means for solving problems]

According to the present invention, a recording electrode and a magnetic toner developing device are arranged opposite to each other via an insulating recording body, and a plurality of recording electrodes are arranged opposite to the recording electrode on a sleeve containing a magnetic roller of the magnetic toner developing device. A counter electrode divided into segments is arranged, and a voltage is selectively applied between the recording electrode and the counter electrode to form a toner image on the fast-edge recording medium, and then the toner image is transferred to recording paper. At the same time as the transfer, the electric charge of the magnetic toner remaining on the insulating recording medium is removed, and the remaining magnetic toner is collected by the magnetic force of the magnetic toner developing machine while repeatedly recording. This problem is solved by an electrostatic recording device characterized by using a recording electrode in which a magnetic material is provided at the tip of the recording electrode and in a position close to the recording electrode needle constituting the recording electrode.

〔Example〕

Embodiments of the present invention will be described below based on the drawings.

FIG. 1 is a schematic diagram showing an embodiment of the present invention.

In this embodiment, a part of the mold member 22 made of glass epoxy resin or the like that fixes the recording electrode needle 2 is mechanically scraped off, and a magnetic material 23 is attached at that position. The behavior of the toner on the sleeve was observed when the magnetic material was pure iron, the distance l between the recording electrode needle and the edge of the magnetic material was 0.3, and the width β' of the magnetic material was 5. Figure 2 (1
), (21, (As shown in 31, it was confirmed that the toner 6a always stands y' upright near the recording electrode needle, regardless of the position of the magnetic poles N and S of the magnetic roller.Furthermore, evaluation was made using the output image. As a result, no image loss was observed, demonstrating that it was highly effective in suppressing image loss.Subsequent investigations revealed that the toner stands more firmly upright at the edge of the magnetic material (point A, Figure 1). The distance between the recording electrode needle and the edge of the magnetic material (Fig. 1, 7) is preferably 211 or less. Fig. 3 summarizes the effects of this embodiment.

As shown in FIG. 3, according to the present invention, image loss can be completely suppressed and a sharp output image without stains in the image background can be obtained. Although pure iron is used as the magnetic material 23 in this embodiment, the same effect can be obtained using other magnetic materials such as silicon iron ferrite.

〔Effect of the invention〕

As explained above, according to the present invention, the toner on the surface of the magnetic roller is always in an upright state near the recording electrode needle regardless of the magnetic pole position of the magnetic roller, so that image loss can be completely suppressed. A sharp output image without stains in the image background can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing an embodiment of the recording electrode of the present invention, FIG. 2 is a schematic diagram showing the effects of the present invention, and FIG. 3 is a diagram showing image evaluation of the present invention. FIG. 4 is a schematic diagram showing another embodiment of the recording electrode of the present invention, FIG. 5 is a perspective view of the recording section of a conventional electrostatic recording device, and FIG. 6 is a recording principle of the electrostatic recording device. FIG. 7 is a schematic diagram showing a conventional electrostatic recording device, and FIG. 8 is a schematic diagram showing a conventional image loss. 1... Recording electrode, 2... Electrode needle, 3...
Insulating recording body, 4... Cylindrical sleeve, 5... Magnetic roller, 6... Magnetic toner developing device, 6a... Toner, 7... Counter electrode, 8.9.
10...roller, 12...recording paper, 13...
Transfer roller, 14...Fuser, 16, 17...
・Corona static eliminator, 18...Mold member, 19...Magnetic material. Example 1 - Recording electrode 2, - Electrode meter 22 - Mold member 23 - Magnetic material ○ Good / Medium Image evaluation of the present invention Fig. 3 Fig. 4 110. Recording electrode 2 - Electrode needle Figure 5 Schematic diagram showing the recording principle Figure 6 18 - Magnetic brush 19 - Toner image 20 - Latent image charger τ Conventional electrostatic recording device Figure 7 12 - Recording paper 139 ．． -Transfer roller +6.17. --Corona static eliminator (a) Figure 8 1 formula diagram showing conventional image loss

Claims (1)

[Claims] A recording electrode and a magnetic toner developing device are disposed facing each other via an insulating recording material, and a counter electrode divided into a plurality of segments is provided on a sleeve containing a magnetic roller of the magnetic toner developing device, facing the recording electrode. After forming a toner image on the insulating recording material by selectively applying a voltage between the recording electrode and the opposing electrode, the toner image is transferred to the recording paper, and the toner image is transferred to the insulating recording material. In a recording device that repeatedly performs recording while removing the electric charge of the residual magnetic toner and collecting the residual magnetic toner by the magnetic force of the magnetic toner developing machine, at the tip of the recording electrode that comes into contact with the insulating recording material, and An electrostatic recording device characterized by using a recording electrode in which a magnetic material is provided in a position close to a recording electrode needle constituting the recording electrode.