JPS5957269A - Direct recording device - Google Patents

Abstract

PURPOSE:To eliminate completely the potential of a residual toner, and to prevent deterioration of a printing quality, by constituting so that alternating voltage destaticizers for eliminating the charge of a residual magnetic toner are opposed to both faces of an insulating recording body, respectively, and each alternating voltage phase impressed to the destaticizers is inverted. CONSTITUTION:In a position where a residual toner passes through, a destaticizers 26 and 27 are placed on both faces of an insulating recording body 3, respectively. Subsequently, alternating voltage which is different 180 deg. in phase to each other by electric power sources 28, 29 is impressed to each destaticizer. By placing the destaticizer on both the surface and the reverse side in this way and impressing the altenating voltage which is different in phase, charge placed on the recessed part of an uneven layer 21 becomes a neutralized form. Also, corona discharge can be stabilized by placing grids 30, 31 on the opening part of the destaticizers 27, 27 and both the faces can be destaticized uniformly. Also, other effect by which printing density can be adjusted is obtained by controlling the voltage impressed to the grids 30, 31, by an electric power source 32.

Description

DETAILED DESCRIPTION OF THE INVENTION (A) Technical Field of the Invention The present invention is directed to a direct recording device, particularly for facsimile image output, etc., in which a recording electrode and a magnetic toner developer are disposed via an insulating recording material. In a direct recording device in which toner (9) is formed on an insulating recording medium and transferred to a recording paper at the same time as an image signal is applied, a static eliminator is installed to remove the electric charge of the toner remaining on the insulating recording medium. This invention relates to a contact recording apparatus in which the removal rate is increased by applying alternating voltages having mutually reversed phases to both sides of an insulating recording medium.

(B) Technical Background and Problems Although the details of the recording principle and structure of direct recording as referred to in the present invention have been previously proposed by the present inventors and a patent application has been filed, an overview of the direct recording will be summarized below. Let me explain.

Figure 1 shows the configuration of the printing section, with the recording electrode 1
constitutes a multi-stylus electrode in which electrode sets 2 consisting of a plurality of groups 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, inside the fixed cylindrical sleeve 4, a magnetic toner developing device 6 having a rotating magnetic roller 5 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.

To perform recording, magnetic toner is transferred from the toner developing device 6 to the outer circumference of the cylindrical sleeve 4, a voltage is applied to the recording electrode needle 2 in accordance with the image signal, and a voltage of opposite polarity is applied to the opposing electrode 7. By selectively applying a voltage, the magnetic toner carried on the selected segment is charged,
A toner image is formed by adhering magnetic toner to the insulating recording medium 3.

Figure 2 shows the overall configuration of the recording device, with reference numeral 1.3.
．． 4.6.7 corresponds to FIG.

The insulating recording body 3 is made of a dielectric film in the form of a belt and is rotated at a constant speed by a cylinder 8.9, IO. 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 40 is installed facing the recording electrode 1.

After forming a toner image on the insulating recording medium 3 as explained with reference to FIG. The toner image is transferred onto the recording paper 12 using the roller transfer 13 from the back side. Thereafter, the transfer (image) on the recording paper 12 is fixed on the recording paper 12 by the pressure fixing device 14. On the other hand, the insulating recording body 3 is further rotated, and the corona static eliminator 16 The charge of the magnetic toner remaining on the insulating recording body 3 is erased and the adhesion force of the toner to the insulating recording body 3 is weakened.The insulating recording body 3 is rotated and conveyed to the printing section. Then, the remaining magnetic toner is collected by the magnetic force of the magnetic roller in the magnetic toner developing device 6.

FIG. 3 shows a state in which a voltage is applied to the electrode needle 2.
Magnetic toner is deposited on the insulating recording medium 3 to form a toner image 1.
9 is enlarged and explained. Reference numerals 2.3.4.5.7 in the figure correspond to FIGS. 1 and 2. When a voltage pulse is 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, as is well known in the art, the top of the cylindrical sleeve 4 (therefore, the counter electrode 7 The tip of the magnetic brush 18 formed on the magnetic brush 18 is charged to the iE polarity, and a negative charge 20 remains on the surface of the electrode fi'+ 211111 of the insulating recording body 3. As a result, as the insulating recording medium 3 moves, the tip of the magnetic brush 18 is cut off by the electrostatic force that overcomes the attraction force caused by the magnetic force, and the magnetic toner is deposited on the insulating recording medium 3. An image 19 is formed.

Note that a concavo-convex layer 21 having a predetermined thickness D is formed on the electrode side 29111 surface of the insulating recording body 3.

The uneven layer 21 can be thought of as keeping the electrode side 2 at a predetermined distance from the base film of the insulating recording medium 30, and consists of insulating bead-shaped spacers and a binder material that holds the spacer material. It can be thought of as consisting of.

As described above, the recording process is repeated to output an image, and such a direct MeF'l device simultaneously performs the latent image formation process using the recording electrode and the development process using the developing machine. Therefore, recording devices such as facsimile machines have the advantage of being simpler in structure, smaller in size, and lower in price.

Further, since magnetic toner is used, untransferred toner can be collected in a developing machine without cleaning and can be used again, which has the advantage of easy maintenance and low consumables prices.

[7] However, because the uneven layer 21 is formed on the insulating recording body 3 as described above, as shown in FIG.
Simply providing the corona charge remover 16 may not be able to completely remove the charge on the residual toner. FIG. 4 shows an enlarged view of the process performed by the corona static eliminator 16, and the reference numerals 3, 8, 16, and 21 in the figure correspond to those in FIGS. 1 to 3.

22 is for residual toner; 231-J is for residual toner;
The C2 charge image, 24 represents the residual toner whose charge could not be removed, and 25 represents the charge.

When the recording medium 3 reaches the position of the grounded cylinder 8 with the residual toner 22 on the insulating recording medium 3, the residual toner 22 is generally removed by the corona static eliminator 16.
The charges on 2 and the charge image 23 should be neutralized. However, the charges located in the concave portions of the uneven layer 21 are likely not to be completely removed through the cylinder 8. In this case, the remaining toner 24 is returned to the developing machine without its charge being removed, but the undesired residual toner 24 cannot be removed from the insulating recording medium 3 before proceeding to the next recording step. That is, although it should be cleaned by the magnetic force of the magnetic roller 5 in the current fJ machine 6, if there is any charge remaining, such as the residual toner 24, it will adhere to the insulating recording medium 3 due to electrostatic force. It will remain as it is and proceed to the next recording process.

Even more serious is that if there is a spot where static electricity is not removed as described above, abnormal discharge will occur when the insulating recording material 3 is peeled off from the cylinder 8, and as a result, printing will not be possible. If a root-like or spot-like pattern appears during printing, printing defects may occur.

As a means for removing the charge of the residual toner on the insulating recording body 3, as a counter electrode of the upper n1 cycorona static eliminator 16,
It is also possible to provide a conductive brush in the cylinder 8 shown in FIG. 4 to remove the electric charge. However, even with this method, a sufficient solution cannot be obtained.

(C) Object and Structure of the Invention The present invention aims to solve the problems listed in -1 and 2, and aims to enable efficient cleaning. Therefore, in the direct recording device of the present invention, a recording electrode and a magnetic toner developing machine are disposed opposite to each other via an insulating recording body, and the recording electrode is placed on a sleeve of a magnetic roller that goes into the magnetic toner developing machine, facing the recording electrode. A plurality of opposing electrodes are arranged, and a voltage is selectively applied to the recording electrode and the opposing electrode to form a toner image on the insulating recording material and transferring it to the recording paper. In a direct recording device that performs repeated recording while removing the charge of magnetic toner remaining on the recording medium by corona discharge,
The alternating voltage static eliminators for removing the charges of the residual magnetic toner are arranged to face both sides of the insulating recording medium, and the phases of the alternating voltages applied to the static eliminators are reversed. It is said that This will be explained below with reference to the drawings.

(D) Embodiment of the Invention Fig. 5 (A) (F3) (0) shows the configuration of an embodiment of the static eliminator used in the recording apparatus of the present invention, and Fig. 6 shows the static eliminator shown in Fig. 5 and the voltage applied to the device. This shows the alternating voltage waveform. Further, FIG. 7 is an explanatory diagram for explaining the effect of static elimination by the static eliminator used in the present invention, and FIG. 8 is an explanatory diagram for explaining an aspect useful for adjusting print density when the configuration shown in FIG. 5(C) is used. Show the diagram.

In FIG. 5, numeral 3.21 corresponds to FIG. 4, and 26
．． 27 is a static eliminator, and 28.29 is an alternating voltage generator.
#4 source, 30.31 represents the crid, 32 represents the bias frost, source, respectively.

In the case of the present invention, for example, as shown in FIG. 5(A), static eliminators 26 and 27 are respectively disposed on both sides of the insulating recording medium 30 at positions through which residual toner passes. Then, for each static eliminator, the sixth
As shown in the figure, alternating voltages having a phase difference of 180' are applied.

In this way, by arranging static eliminators on both the front and back surfaces and applying alternating voltages with different phases, for example, the uneven layer 2
The charges located in the four parts of 1 are also correctly neutralized,
The undesirable aspect described in connection with FIG. 4 is eliminated.

Figure 7 shows the case (A) in which a static eliminator is placed only at h as shown in Figure 4, and the case (A) in which a static eliminator is placed on both sides, but the static eliminator is placed in the same phase. An alternating voltage was applied. Singing (B
) and the case (0) in which static eliminators are not disposed on both sides and alternating voltages with different iL phases are applied as shown in FIG. 5(A) are compared. Note that the static elimination efficiency (
” / ) x lUO[chi]O. However, Vo is latent tI! Potential, ■ is the drop l・'iI+' due to static electricity removal, (i7., > represents (
-1.

FIG. 5(A) In the case of the illustrated form, the applied voltage is hc5,5
It can be seen that substantially 100% static electricity removal is performed at KV or higher.

In the configurations shown in FIGS. 5(B) and 5(C), grids 30, 31 are arranged at the openings of the static eliminators 26, 27. By arranging the grids 30 and 31 in this manner, corona discharge can be stabilized, and it becomes possible to perform uniform static elimination on both sides.

In addition, in the case of the configuration shown in FIG. 5(0), the grid 30
．． The voltage applied to 31 is controlled by the power supply 32 1iIl+
○This twisting provides another effect of being able to adjust the print density. Figure 8 shows the state (D) in which the surface potential changes in response to the DC voltage (bias voltage E) applied to the grid, and the print density (detection) when printing is performed. .

(K) As described in detail, according to the present invention, it is possible to completely remove the potential of toner remaining on an insulating recording medium, and it is possible to prevent deterioration of print quality. Become.

BRIEF DESCRIPTION OF THE DRAWINGS FIGS. 1 and 2 are explanatory diagrams illustrating the outline of the direct recording device according to the present invention. Figures 3 and 4 are explanatory diagrams explaining the prerequisite problem of the present invention, Figure 5 (A) (J3)
(0) shows an example configuration of a static eliminator used in the recording apparatus of the present invention, and FIG. 6 shows a typical voltage waveform applied to the static eliminator shown in FIG. +P, Fig. 7 is an explanatory diagram illustrating the effect of static elimination by the static eliminator used in the present invention, and Fig. 8 explains an aspect useful for adjusting print density when using the configuration shown in Fig. 5 (0). An explanatory diagram is shown. In the figure, 1 is a recording device, 2 is a plate with poles, 3 is an insulating recording body, 4 is a cylindrical sleeve, 5 is a magnetic roller, 6 is a magnetic toner developer, 7 is a counter electrode, 8.9, IO is cylinder respectively,
12 is a recording paper, 14 is a fixing device, 16 is a static eliminator, 19 is a toner box, 21fd is an uneven layer, 26 and 27 are static eliminators,
Reference numerals 28 and 29 represent master voltage generation power supplies, 30 and 31 represent grids, respectively, and 32 represents a bias power supply. Patent applicant Hiroshi Mori Fguchi (1 other person), Fujitsu Ltd. agent patent attorney

Claims (1)

[Claims] A recording electrode and a magnetic toner developing machine are disposed opposite to each other with an insulating recording body interposed therebetween, and a plurality of opposing cylinders are arranged opposite to the recording electrode on the sleeve of a magnetic roller in the magnetic toner developing machine.
A voltage is selectively applied to the recording electrode and the counter electrode to form a toner image on the insulating recording medium, and the toner image is transferred to the recording paper, and the toner image is transferred to the recording paper. In a direct recording device that performs repeated recording while removing the charge of magnetic toner remaining on the body by corona discharge,
Note: The present invention is characterized in that alternating voltage static eliminators for removing charges of residual magnetic toner are placed opposite to both sides of the insulating recording medium, and the phases of the alternating voltages applied to the static eliminators are reversed. direct recording device.