JPS63270159A - Driving method for electrostatic latent image-forming device - Google Patents

Abstract

PURPOSE:To ensure a high efficiency in utilizing ions and enable stable electric discharge, higher speed and higher density, by providing a switching means and a judging means, and applying an AC voltage to independent electrodes, applying a DC voltage to the electrodes or setting the electrodes into a floating condition according to data inputted. CONSTITUTION:Electrodes 2a-2d are coated with an insulator layer 3, on which a common electrode 4 is provided. Each of the electrodes is switchably connected to a DC power source 9 or to both an AC power source 10 and the DC power source 9 through a switching means Z. The switching means Z comprises switches Sa-Sd, which are controlled by output signals from a data input means X and a judging means Y. Each of the switches Sa-Sd is constituted of a contact G connected to the DC power source, a contact A connected to the AC power source and a contact F in a neutral position, and can be connected to the AC power source with a DC voltage superimposed thereon, connected to the DC power source or set into a neutral so-called floating condition, through the switching means Z. Since electric discharge is performed between the electrodes through the insulator layer, ionic efficiency is favorable, abnormal discharge such as leakage between the electrodes is prevented from occurring, and stable electric discharge is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method of driving an electrostatic latent image forming device that modulates ion flow to form an electrostatic latent image on a dielectric material. [Prior Art] In general, the principle of electrostatic recording using an ion flow is explained with reference to FIG. 5. Ions generated in the electrostatic recording head 11 form an electrostatic latent image on the recording medium on the surface of the rotating drum 12. 13
A developing agent such as toner is applied to the electrostatic latent image 13 by a developing device 14 to form a toner image 15, and the toner image 15 is transferred to the recording paper 17 in the transfer section 16, thereby forming an electrostatic latent image. Electronic records are made. After the recording medium is neutralized by the static eliminating section 18, the remaining developer is removed by the toner removing section 19 in preparation for the next recording.

Conventionally, the ion flow generation method in the electrostatic latent image forming apparatus described above involves arranging pin-shaped electrodes in a row and bringing them into contact with a dielectric material.
A direct electrostatic recording method is known in which a discharge is caused directly between the electrode and the dielectric, but the gap between the electrode and the dielectric must be maintained with high precision, and the discharge cannot be stabilized. However, there were drawbacks such as electrode wear.

In order to eliminate the above drawbacks, various indirect electrostatic recording methods are known. For example, FIG.
This is a method proposed in Japanese Patent No. 63, in which the corona ion generator 11 has a corona wire 21 built into the shield 20, and an insulating layer 23 is provided at the bottom of the ion generator 11.
A common electrode 22a and a control electrode 22b are provided on both sides,
Ions generated in the ion generator 11 are led out from the ion passage hole 24 to charge the dielectric 25 according to the electric field strength between the common electrode 22a and the control electrode 22b.

Further, FIG. 7 shows a method proposed in Japanese Patent Application Laid-Open No. 58-132571, in which discharge electrodes 27a and 27b are arranged facing each other on one surface of an insulating substrate 26, and the other side of the vA edge substrate 26 is An acceleration electrode 28 is provided on the surface, and by applying voltage pulses with different polarities between the discharge electrodes 27a and 27b, a discharge is caused to generate positive and negative ions, and the voltage pulse to the acceleration electrode 28 is applied. Depending on the dielectric 2
5 is charged with positive or negative ions.

FIG. 8 shows a method proposed in U.S. Pat. No. 4,160,257, in which drive electrodes 3
1 and a control electrode 32 are formed, and further a common electrode 34 is formed with an insulating layer 33 interposed therebetween. The drive electrode 31 and the control electrode 32 are arranged in a matrix so that their directions are different from each other, and a plurality of openings 35 and 36 are formed in the insulating layer 33 and the common electrode 34 in correspondence with the matrix. By selectively applying an AC voltage between the plurality of drive electrodes 31 and control electrodes 32, positive and
Negative ions are generated, and electrostatic recording is performed by leading out positive or negative ions from the openings 35 and 36 depending on the polarity of the bias voltage between the discharge electrode 32 and the common electrode 34.

[Problem that the invention seeks to solve]

However, in the wire discharge method shown in FIG. 6, the ions generated by corona discharge are far from the aperture area, so most of them are absorbed by the shield 20, and the ions passing through the aperture electrodes 22a and 22b The problem is that the flow is low and the ion utilization efficiency is poor.

In addition, in the method of discharging using electrodes as shown in Fig. 7, the electrodes are exposed, so leaks are likely to occur, and since the electrodes are directly discharged, the electrodes are easily damaged, and the number of electrodes is small. Many of them have the problem of high density and difficult wiring.

In addition, in the example shown in FIG. 8, there are relatively few problems mentioned above, but since matrix driving is essential,
When forming a latent image on one line, it is necessary to rearrange and align the data, and it is difficult to increase the speed.
As a result, there is a problem in that a complicated control circuit is required and the device becomes larger.

The present invention solves the above-mentioned problems, and provides a method for driving an electrostatic latent image forming device that has high ion utilization efficiency, enables stable discharge, and is capable of increasing speed and density. The purpose is to

[Means for solving problems]

To this end, the method for driving an electrostatic latent image forming device of the present invention includes a group of electrodes arranged independently of each other on a substrate, and a common electrode facing the group of electrodes with an insulating layer in between. An electrostatic latent image forming device, comprising a switching means and a determining means,
The present invention is characterized in that the independent electrode is caused to be in any one of an AC voltage application, a DC voltage application, or a float state depending on input data.

[Effect]

In the present invention, for example, in the voltage application state shown in FIG. 1, an alternating electric field is formed in one discharge region A between the electrodes 2a and 2b, air breakdown or creeping discharge occurs, and ions are The generated ions are led out of the discharge area A and out of the opening 5 of the common electrode 4 by the electric field formed between the common electrode 4 and the independent electrode group 2, and the led out ions are It is accelerated by the electric field formed between the electrode 4 and the dielectric layer 7 and base layer 6, and reaches the surface of the dielectric JiE 17 to form an electrostatic latent image. On the other hand, no alternating electric field exists between the electrode 2b and the electrode 20 and between the electrode 2C and the electrode 2d, so that no ions are generated and no electrostatic latent image is formed.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings. 1st
The figure is a cross-sectional view showing one embodiment of an electrostatic latent image forming device to which the present invention is applicable, and FIG. 2 is a perspective view of the electrode section in FIG.
FIG. 3 is a block diagram showing one embodiment of a driving method for an electrostatic latent image forming apparatus according to the present invention, and FIG. 4 is a diagram for explaining the present invention in detail.

In the figure, l is a base, 2 is an electrode group, 28 to 2d are electrodes, 3 is an insulating layer, 4 is a common electrode, 5 is an opening, 6 is a base layer, 7 is a dielectric layer, 8.9 is a DC power supply, 10 indicates an AC power supply, X indicates a data manual means, Y indicates a judgment means, and Z indicates a switching means.

In FIGS. 1 and 2, electrodes 2as2bs2C12d forming a mutually independent electrode group 2 on the base 1,
... are arranged in parallel, each of the electrodes 2a to 2d is coated with an insulation N3, and a common electrode 4 is disposed on the insulation N3. Openings 5 are formed facing each other between the electrodes 2a to 2d. Further, a dielectric layer 7 is formed on the base layer 6, and the dielectric layer 117
is arranged facing the common electrode 4, and the base layer 6 is grounded. On the other hand, a bias voltage is applied to the common electrode 4 by a DC power supply 8, and for example,
A DC voltage is applied to the electrode 2a by a DC power supply 9, and an AC voltage multiplied by the DC voltage is applied to the electrode 2b from the AC power supply 1.
0, and the electrode 2C12d is in a floating state with no voltage applied.

Next, the operation of the present invention having the above configuration will be explained. In the voltage application state shown in FIG. Creeping discharge occurs,
ions are generated.

The generated ions are led out of the discharge area A and out of the opening 5 of the common electrode 4 by the electric field formed between the common electrode 4 and the independent electrode group 2, and the led out ions are drawn out from the common electrode 4 and outside the opening 5 of the common electrode 4. It is accelerated by the electric field formed between the dielectric layer 7 and the base layer 6, reaches the surface of the dielectric layer 7, and forms an electrostatic latent image. On the other hand, there is no alternating electric field between the electrode 2b and the electrode 20 and between the electrode 2C and the electrode 2d, and no ions are generated. No image is formed either.

The polarity of the electrostatic latent image to be formed, that is, the polarity of the ions to be taken out, can be made positive or negative by changing the polarity of the DC voltage applied to the electrode group 2 and the common electrode 4 and the bias voltage applied to the common electrode 4. For example, if you keep the DC voltage at -5oov and the bias voltage at -600V, a negative latent image can be formed, and if you keep the DC voltage at +800V,
If the bias voltage is kept at +600V, a positive latent image can be formed. Further, the voltage of the AC power source needs to be set higher than the voltage at which discharge starts between the electrode group 2 and low enough to prevent abnormal discharge, but the set value is determined by the distance between the electrodes and the like. Further, the frequency of AC may be any value as long as it causes discharge, and can be used in the range of several tens of Hz to several MHz.

FIG. 3 shows a method of driving the electrodes 2a, 2b, 2c, and 2d. Each electrode is connected to the DC power R9 alone or to the AC power source 10 and the DC power R9 via a switching means Z, and the switching means Z is the switch Sa s s b ,, s
c % S d, and each switch is controlled by the output signals of the data input means X and the judgment means Y. Each switch Sa to Sd has a contact G connected to a DC power supply.
, a contact A connected to an AC power supply, and a contact F in a neutral position, and each electrode is connected to an AC power supply with a DC multiplier by removing the switching means Z, or is connected to a DC power supply. It is possible to create either one of the so-called floating states, which are connected or not connected to anything, which is a neutral state.

An example of the operation will be explained with reference to FIG.

In the figure, A indicates AC application, G indicates DC application, F indicates a floating state, oeo indicates a controlled dot, ◯ indicates a dot that is not printed, and * indicates a dot that is printed. (
(a) shows a case in which all dots are printed, which is achieved by alternately repeating alternating current application and direct current application; (b) shows a case in which all dots are not printed, with all electrodes in a floating state. (c) and (d) show cases in which there are two or more unprinted dots, and if (number of unprinted dots - 1) electrodes are floated between repetitions of A and G, G-F, F
Since no electric field is formed between -A, no ions are generated and no printing is performed. In addition, (e) to (g) indicate cases where one or more non-printed dots do not continue. All you have to do is,
If both electrodes of a dot that is not to be printed are placed in the A-A or GG state, no alternating electric field exists between the two electrodes, resulting in a non-printing state.

Note that the electrode driving method is not limited to the example shown in FIG. 4, and various methods can be considered. In short, the electrodes on both sides of the dot to be printed should be in the A-G relationship, and when not printing, the other should be in the A or F relationship when one is in the state, and one is in the G relationship. state, the other is G or F
The driving state of the electrodes is achieved by the determining means Y instructing the switching means Z to perform switching according to the input data. Specifically, a method similar to a data compression method often used in the field of communication technology, for example, input data and a ROM compressed in advance.
This can be achieved by comparing with the permutations written in the table, but the method is not limited to the above method and various methods can be used.

〔Effect of the invention〕

As explained above, the present invention provides an electrostatic latent image having a group of electrodes arranged independently of each other on a substrate, and a common electrode facing the electrode group with an insulating layer in between. The forming apparatus includes a switching means and a determining means, and causes the independent electrode to be in any of the following states: AC voltage application, DC voltage application, or floating state, depending on the input data. An effect like this is produced.

(a) Since the discharge is caused between the electrodes via the insulating layer, the ion efficiency is high, and abnormal discharge such as leakage between the electrodes is prevented, and stable discharge can be obtained.

(b) There is no need to set up a matrix for printing, and one line can be printed all at once, increasing the printing speed.

(c) Since the electrode groups are arranged in parallel, manufacturing is simple, the number of electrodes is small, wiring is easy, and high density is possible.

(d) Compared to direct electrostatic recording, maintaining a narrow gap between the electrode and the dielectric is not required, and there is less wear on the electrode.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing one embodiment of an electrostatic latent image forming apparatus to which the present invention is applied, FIG. 2 is a perspective view of the electrode section in FIG. 1, and FIG. 3 is an electrostatic latent image forming apparatus according to the present invention. Forming device driving method 1
FIG. 4 is a block diagram showing an embodiment, FIG. 4 is a diagram for explaining the present invention in detail, FIG. 5 is a diagram for explaining the principle of the electrostatic latent image forming apparatus, FIGS. FIG. 8 is a diagram for explaining a conventional electrostatic latent image forming apparatus. DESCRIPTION OF SYMBOLS 1... Base body, 2... Electrode group, 2a-2d... Electrode, 3... Insulating layer, 4... Common electrode, 5... Opening,
6... Base layer, 7... Dielectric layer, 8.9... DC power supply, 10... AC power supply, X... Data input means, Y
...judgment means, Z...switching means. Applicant: Fuji Xerox Co., Ltd. Representative Patent Attorney Hiroki Shirai (2 others) Figure 1 A Figure 2 Figure 3 Electronic Snoring Figure 4 (2) RoOro Senn@MJO Roo Prisoner 0 Figure 5, Figure 6, Figure 7 (Q,) (Figure 8)

Claims (1)

[Claims] (1) In an electrostatic latent image forming device having a group of electrodes arranged independently of each other on a substrate and a common electrode facing the electrode group with an insulating layer interposed therebetween, a switching means and a determining means are provided. and AC to the independent electrode according to input data.
1. A method for driving an electrostatic latent image forming apparatus, characterized in that any one of a voltage application, a DC voltage application, and a float state is caused.