JPH032070B2 - - Google Patents

Description

[Detailed Description of the Invention] [Summary] To prevent deterioration of recording characteristics due to the magnetic material provided near the tip of the recording electrode coming into contact with the insulating recording body and being worn out and adhering to the insulating recording body. , the magnetic material is prevented from coming into contact with the insulating recording medium.

[Industrial application field]

The present invention relates to an image recording device used in facsimile machines, printers, etc., and in particular, a recording electrode and a magnetic toner developing device are arranged through an insulating recording body, and a toner image is formed on the insulating recording body at the same time as an image signal is applied. The present invention relates to a technique for improving the image quality of an output image in a configuration in which a magnetic material is provided near the recording electrode of a recording device.

[Conventional technology]

Although the details of the recording principle and configuration of the recording device to which the present invention relates have been previously proposed and patented by the present inventors, an outline of the recording device will be explained once again.

FIG. 3 shows the configuration of the recording section, and the recording electrode 1 constitutes a multi-stylus in which electrode needles 2 consisting of a plurality of groups are arranged in a line. An insulating recording body 3 made of a dielectric film is brought into contact with the recording electrode 1. On the other hand, a rotating magnetic roller 5 is placed inside the fixed cylindrical sleeve 4.
A magnetic toner developing device 6 having a magnetic toner developing device 6 is installed 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. By doing so, magnetic toner is attached to the insulating recording medium 3 to form a toner image.

FIG. 4 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. Reference numerals 2, 3, 4, 5, and 7 in the figure correspond to those in 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, and is attracted to the Coulomb force of the latent image charge 20 to form 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. 5 shows the overall configuration of the recording apparatus, and the symbols 1, 3, 4, 6, and 7 in the figure correspond to those in FIG. The insulating recording material 3 is made of a dielectric film formed into a belt and rotated at a constant speed by rollers 8, 9, and 10. 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 described with reference to FIGS. 3 and 4, 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 the insulating recording body 3
When corona static eliminators 16 and 17 are placed opposite each other on both sides of the recording medium 3, when alternating voltages with different phases are applied to each corona static eliminator, the charge of the magnetic toner remaining on the insulating recording medium 3 is removed. The magnetic toner 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 rotated and conveyed to the 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 simultaneously performs the latent image formation process by the recording electrode and the development process by the developing machine, the output of a facsimile etc. The device has the advantage of being simpler in configuration, smaller in size, and lower in price. Furthermore, since magnetic toner is used, untransferred toner can be collected in a developing machine and reused without cleaning, so maintenance is easy and consumables prices are low.

[Problem that the invention seeks to solve]

Incidentally, in such a recording apparatus, magnetic toner is conveyed only by rotation of the magnetic roller 5 of the toner developing device 6. For this reason, image loss occurs depending on how the magnetic brush stands.

The reason for this is that when the magnetic roller rotates and the recording electrode and the magnetic roller's magnetic poles face each other, the toner does not stand upright but lies down on the cylindrical sleeve. In the worst case, if there is no contact, image loss will occur in this state.

As a preventive measure, it is effective to provide a magnetic material at the tip of the electrode and near the recording electrode needle.
The inventors proposed this configuration in Japanese Patent Application No. 156909/1983.

The main part of this configuration is shown in FIG.

As shown in this figure, when the magnetic material 52 is placed in contact with the insulating recording medium 3, there is a problem in that the magnetic material is abraded and abrasion powder 54 adheres to the back surface of the film, preventing image formation. Furthermore, when a conductive magnetic material is used, there is a problem in that fog occurs on the insulating recording body at a position facing the counter electrode. In this way, fogging occurs at the position facing the counter electrode on the insulating recording material when a voltage is applied to the counter electrode, especially when a conductive magnetic material is used, as shown in Figure 7. Induced charge 2 on the surface of magnetic material
It is thought that 0 appears and this charge rides on the surface of the recording medium, causing toner 19 to adhere and fogging to occur.

[Means for solving problems]

By configuring the insulating recording body and the magnetic material not to be in contact with each other, it is possible to prevent charges from being transferred from the magnetic material onto the insulating recording body.

〔Example〕

An embodiment of the present invention is shown in FIG. In this embodiment, a part of the mold member 51 made of glass epoxy resin or the like that fixes the recording electrode needle 2 is shaved off, and a magnetic material 52 is attached at that position.
The magnetic material 52 is attached at a distance of approximately 1 mm from the tip of the electrode that is in contact with the insulating recording material 3, so that it does not come into contact with the insulating recording material 3. This eliminates magnetic powder produced by abrasion of the magnetic material.

FIG. 2 shows another embodiment of the present invention,
The difference from FIG. 1 is that a magnetic material 52 is molded inside an insulating mold member 51. In this embodiment, the tip of the electrode is arc-shaped, and the insulating recording material is less likely to be damaged. Furthermore, abrasion powder from the mold member 51 adheres to the back surface of the insulating recording medium, but does not affect image formation.

By not bringing the insulating recording material into contact with the magnetic material in this manner, charges will not be transferred from the magnetic material onto the recording material. When the output image was evaluated, an image without fog was obtained. It was also confirmed that there was no magnetic powder caused by wear.

〔Effect of the invention〕

According to the present invention, since the magnetic material is not in contact with the insulating recording material, the magnetic material does not wear out and fogging can be prevented.

[Brief explanation of the drawing]

FIG. 1 and FIG. 2 are diagrams showing an embodiment of the present invention. FIG. 3 is a configuration diagram of a recording section to which the present invention is applied;
FIG. 4 is a diagram showing the principle of electrostatic recording, FIG. 5 is a diagram showing the overall configuration of an electrostatic recording apparatus, and FIGS. 6 and 7 are diagrams showing conventional examples. In the figure, 51 is a mold member, 52 is a magnetic material, 2 is a recording electrode needle, and 3 is an insulating recording body.

Claims (1)

[Scope of Claims] 1. A recording electrode and a magnetic toner developing device are disposed facing each other with an insulating recording body interposed therebetween, and a plurality of segments 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 two is disposed, and a voltage is selectively applied between the recording electrode and the counter electrode to form a toner image on the insulating recording body, and then the toner image is transferred to recording paper. , at the tip of the recording electrode of a recording device that repeatedly performs recording while removing the charge of the magnetic toner remaining on the insulating recording medium and collecting the remaining magnetic toner by the magnetic force of the magnetic toner developing machine; An electrostatic recording device, characterized in that the electrode has a structure in which a magnetic material is provided in a position close to a recording electrode needle constituting the electrode, and the electrode is configured such that the insulating recording material and the magnetic material do not come into contact with each other. 2. The electrostatic recording device according to claim 1, wherein the magnetic material is housed in a mold together with the recording electrode.