JPS63265659A - Electrostatic recording head - Google Patents

Abstract

PURPOSE:To contrive a reduction in power consumption at an ion-generating part through effective use of generated ions, by disposing an induction electrode on the downstream side of a discharge electrode in the ion-generating part. CONSTITUTION:An induction electrode 4a is provided in a thickness of 0.5-5 mum on one side of a ceramic substrate 2 by applying a gold paste by printing, followed by firing. An insulating layer 6 having a thickness of several tens-several thousands of micrometers is provided on the electrode 4a by applying a glass paste by printing, followed by firing. A discharge electrode 5a having a thickness of 0.5-5 mum is provided on the insulating layer 6 by applying a gold paste or platinum paste by printing and then firing the applied paste, in the same manner as in providing the induction electrode 4a. With this construction, ions in a discharge region in which a large quantity of ions is trapped can be rapidly conveyed to a control region, namely, a controlling part Q, and the ions thus generated can be effectively used without losing a large amount of the ions through re-coupling.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a recording head that performs electrostatic recording using an ion stream.

[Conventional technology]

In electrostatic recording devices, an ion flow control type electrostatic recording head is one of the devices that forms an electrostatic latent image on electrostatic recording paper or a dielectric material.

In this electrostatic recording head, a wire to which a high voltage is applied is placed in a chamber formed in a grounded conductive casing, and ions are generated in the chamber. Then, by blowing an air flow from one end of the chamber, ions in the chamber are caused to adhere to the electrostatic recording medium through a slit-like passage formed at the other end of the chamber. A modulation electrode is provided along the ion flow in this path, and the amount of ions passing through the path is controlled by changing the potential of this modulation electrode in accordance with, for example, an image signal. By moving the recording medium perpendicularly to the longitudinal direction of the electrostatic recording head, an electrostatic latent image corresponding to the image is formed on the recording medium.

In this type of electrostatic recording head, for the purpose of speeding up recording, there is one in which ions are generated by generating alternating current discharge between two electrodes that are insulated from each other on one side of the substrate. Patent application 1986-237 by the inventor
It is proposed as No. 532.

FIG. 4 is a diagram showing a schematic configuration of the electrostatic recording head proposed previously.

In this electrostatic recording head, a casing 1 made of synthetic resin and a ceramic substrate 2 are arranged facing each other, and a substantially semi-cylindrical chamber 3 is formed on the surface of the casing 1 facing the ceramic substrate 2. ing. Further, an induction electrode 4 and a discharge electrode 5 are formed on the surface of the ceramic substrate 2 facing the housing 1 with an insulating layer 6 in between, and an AC power source 7 is connected to these electrodes 4.5. In the upper part of the chamber 3, an artificial slit 8 is provided between the housing l and the ceramic substrate 2, and in the lower part of the chamber 3, an exit slit 9 is provided.

A circuit board IO is provided on the lower end surface of the housing 1, and
A grounded conductive plate 11 is provided on the lower end surface of the ceramic substrate 2, and a slit-shaped passage 12 is formed between the circuit board IO and the conductive plate 11. Further, a modulation electrode 13 is provided on the surface of the circuit board 10 facing the exit slit 9, and is connected to the positive electrode of a DC power source 15 via a conductive path 13a and a switch 14. Note that a plurality of modulation electrodes 13 are provided at predetermined intervals in the extending direction of the chamber 3, that is, in a direction perpendicular to the plane of the drawing. These circuit boards 10. Conductive plate 1
11 passage 12. An ion modulation section 16 is configured by the modulation electrode 13 and the like.

In addition, an air inflow duct 17 is provided near the artificial slit 8.
is provided.

An electrostatic recording medium 21 is movably arranged below the ion modulation section 16. This electrostatic recording medium 21 has a structure in which a dielectric layer 23 is provided on the upper surface of a conductive layer 22.
Conductive layer 22 is connected to the negative electrode of DC power supply 24 .

In this electrostatic recording head, when a high frequency voltage is applied to the induction electrode 4 and the discharge electrode 5 from the AC power source 7, both electrodes 4.
During this period, positive and negative ions are generated alternately. These ions enter the chamber 3 from the duct 17 through the artificial slit 8.
It is carried into the passageway 12 by the air flow introduced into the passageway 12.

At this time, the switch 14 is controlled according to the image signal to perform modulation.

That is, among the ions passing through the portion facing the modulation electrode 13 to which a voltage is applied, positive ions adhere to the conductive plate 11 and are neutralized, and negative ions adhere to the modulation electrode 13 and are neutralized. . Furthermore, when no voltage is applied to the modulation electrode 13, both positive and negative ions are carried to the exit of the passage 12. At this time, the positive ions fly toward the electrostatic recording medium 21 due to the electric field between the conductive plate 11 and the conductive layer 22 of the electrostatic recording medium 21, and
However, the negative ions are subjected to a force in the opposite direction due to the influence of the same electric field, fly toward the conductive plate 11, come into contact with the conductive plate 11, and are neutralized. Therefore, an electrostatic latent image is formed on the electrostatic recording medium 21 by positive ions.

In such an electrostatic recording head, the amount of ions generated is larger than that of the conventional head, and the ion transport efficiency is also higher than that of the conventional head. Therefore, even if an image is formed at high speed, a sufficient amount of ions can be supplied for image formation, and the recording speed can be increased with a simple configuration.

In such an electrostatic recording head, it is necessary to reduce power consumption as much as possible. For this reason, it is important to efficiently generate ions, and to efficiently separate the generated ions from the generation section and transport them to the modulation section, that is, the control section.

[Problem that the invention seeks to solve]

However, in the ion flow control type electrostatic recording head shown in FIG. 4, since the centers of the induction electrode 4 and the discharge electrode 5 are aligned,
, 5 are generated. Therefore, ions are generated on both the upstream and downstream sides of the discharge electrode 5.
In particular, in the upstream generation section, the distance to the head exit is longer, and while the positive and negative ions generated at the induction electrode 4 and the discharge electrode 5 are transported toward the exit slit 91 and the passage 12, the positive and negative ions are recombined. and will decrease significantly. Therefore, a portion of the ions generated at both electrodes 4.5 cannot be used as ions for electrostatic recording. For this reason, the ion utilization efficiency is low, and in order to supply a sufficient amount of ions, the discharge current must be increased, resulting in an increase in power consumption.

The present invention was devised in order to solve the above-mentioned problems, and it takes into account the direction of ion transport and sets the positional relationship of electrodes that contribute to ion generation. The aim is to obtain a large amount of ions.

[Means for solving problems]

In order to solve the above-mentioned problems, the present invention provides an electrostatic recording head in which ions from an ion generating section are disposed with an insulating layer interposed between the inductive electrode and the discharging electrode. It is characterized by being arranged downstream of the discharge electrode.

[Effect]

In the present invention, since the conductive electrode is located on the downstream side of the air flow with respect to the discharge electrode, the discharge area is on the downstream side of the ion generating section near the exit side of the head. Thereby, the ions generated in this discharge region are quickly transported to the exit side of the head by the air flow. Therefore, ions that have left the discharge region are less likely to disappear due to recombination during transport. Therefore, the ions generated in the ion generating section can be efficiently used as ions for electrostatic image formation.

〔Example〕

DETAILED DESCRIPTION OF THE INVENTION Hereinafter, features of the present invention will be specifically described based on examples with reference to the drawings.

FIG. 1 shows a partial schematic sectional view of an electrostatic recording head according to an embodiment of the present invention. Note that parts corresponding to those in FIG. 4 are denoted by the same reference numerals, and redundant explanation will be omitted.

In this embodiment as well, similarly to the electrostatic recording head shown in FIG. Electric appliances are configured.

As an example of the configuration of the ion generating part P, the induction electrode 4a is formed to have a thickness of 0.5 to 5 μm by printing gold paste on one side of the ceramic substrate 2 and firing it. and,
Glass paste is printed and fired on this induction electrode 4a to form an insulating layer 6 with a thickness of several tens to several thousand μm, and then gold paste or platinum paste is printed on this insulating layer 6 in the same way as the induction electrode 4a. , thickness 0.5-5μm by firing
A discharge electrode 5a is formed.

In this embodiment, as shown in FIGS. 1 and 2, the induction electrode 4a is located downstream of the discharge electrode 5a. Incidentally, the positional relationship here is assumed to be viewed from the center position of the induction electrode 4a and the discharge electrode 5a in the air flow direction. For example, if the widths of the induction electrode 4& and the discharge electrode 5a in the ion flow direction are equal, the airflow downstream end A of the induction electrode 4a is located downstream of the airflow downstream end B of the discharge electrode 5a. It turns out. The air flow is shown in Figure 2 (a).
It is indicated by C in .

A voltage of several kHz to several tens of MHz, several hundred V to several tens of kVp is applied from an AC power source 7 between the induction electrode 4a and the discharge electrode 5a of the ion generating part P.
When a high frequency high voltage of p is applied, the end of the discharge electrode 5a that overlaps with the induction electrode 4a, that is, the discharge electrode
Discharge begins to occur near the downstream end B of a, and as the discharge becomes stronger, the discharge area spreads along the induction electrode 4a and reaches the downstream end A of the induction electrode 4a. This discharge area is shown by crossed diagonal lines in FIG. Note that if the overlapping portion between the discharge electrode 5a and the induction electrode 4a is too wide, the capacitance will increase and the power consumption will increase, so it is necessary to suppress it to a certain level or less.

When this ion generating section P is driven at a constant frequency and a constant voltage, the discharge distance is longer and the electric field strength is weaker near the downstream end A than near the downstream end B. For this reason, the amount of ions trapped in the unit discharge region is greater near the downstream end A than near the downstream end B for the reason described below.

Now, assuming that the electric field is a sine wave, the distance X that ions move during a half period of electric field change is as follows. However, μ is the mobility, Eyo is the electric field strength, ω is the angular velocity of electric field change, and L is the time.

Under constant voltage application conditions, if the discharge distance is long, the electric field strength E
1 becomes weaker, the distance X that the ions travel becomes smaller, and the probability of reaching the opposing electrode becomes lower. Therefore, as the electric field strength E becomes weaker, the number of ions that cannot reach the counter electrode during a half period of the electric field, that is, the number of trapped ions increases. As a result, the amount of ions gradually increases from near the downstream end B to near the downstream end A.

Positive ions (indicated by e in the figure) and negative ions (indicated by e in the figure) generated by the discharge between the induction electrode 4a and the discharge electrode 5a are e.g. The air flow C (see FIG. 2(a)) having an air pressure of .0 passes through the slit-shaped passage 12 and heads toward the electrostatic recording medium 21. At this time, by applying a ground potential to both control electrodes 11a and 13b formed along the path 12 via a conductive path (not shown), positive and negative ions are allowed to pass through.

Furthermore, by applying a voltage between the control electrodes 11a and 13b, positive ions are deflected and attracted to the control electrode on the side to which a negative voltage is applied, and negative ions are deflected to the control electrode on the side to which a positive voltage is applied. suction to prevent ions from passing through the passageway 12. That is, the control electrodes 11a, 1
The control unit Q provided with 3b controls the passage and blocking of ions.

In addition, the housing 1. Bias electrodes 18 , 19 are provided at the lower end of each of the ceramic substrates 2 , and a DC power source 24 & is connected between these bias electrodes 18 , 19 and the conductive layer 22 of the electrostatic recording medium 21 .

Of the positive and negative ions that have passed through the passage 12, negative ions adhere to bias electrodes 18 and 19 to which a positive voltage is applied and are neutralized. Therefore, only positive ions will eventually adhere to the dielectric layer 23 of the electrostatic recording medium 21.

In the recording method of this embodiment, when the ions generated in the ion generating part P are removed from the discharge area, the existing ions are carried away by wind force when the electric field between the induction electrode 4a and the discharge electrode 5a becomes small. method, it is preferable to have a large number of trapped ions. In addition, the positive and negative ions that have left the discharge area recombine and disappear over time during the subsequent transport process, so they quickly pass through the control unit Q after leaving the discharge area. It is preferable that the recording medium be conveyed to the head outlet.

For the above reasons, in this embodiment, the induction electrode 4a is arranged downstream of the discharge electrode 5a in the air flow. As a result, ions in the discharge region with a large amount of trapped ions can be quickly transported to the control region, that is, the control section Q, and the generated ions can be used effectively without losing a large amount due to recombination. Can be done.

Therefore, when a certain amount of ions is required,
This means that the power consumption of the ion generation fIP can be kept to a minimum. That is, the power consumption is the same as that of the electrode 4a.

It is the sum of the charging/discharging current to the capacitor formed by 5a and the gas (air in this example) discharge current, but the efficiency of ion generation can be increased by increasing the proportion of the gas discharge current with the same power consumption. In addition, it is possible to increase the transport efficiency.

FIG. 3 is an example of a graph showing the relationship between the amount of deviation between the downstream end A of the induction electrode 4a and the downstream end B of the discharge electrode 5a and the amount of ions output from the head. In addition, in this graph, the induction electrode 4a with respect to the discharge electrode 5a
The shift toward the downstream side is shown as positive. As is clear from this graph, by arranging the induction electrode 4a downstream of the discharge electrode 5a, the amount of ions output from the head increases.

〔Effect of the invention〕

As described above, in the present invention, the induction electrode is located downstream of the discharge electrode in the ion generation section. As a result, the downstream side near the head exit becomes a discharge region, and ions leaving the discharge region quickly pass through the control region and are transported to the head exit. Therefore, positive and negative ions generated in the discharge region are less likely to recombine and disappear during the transport process. Therefore, the generated ions can be used effectively, and the power consumption in the ion generation section can be reduced.

[Brief explanation of drawings]

FIG. 1 is a partial schematic sectional view of an electrostatic recording head according to an embodiment of the present invention, FIG. 2(a) is a sectional view of the same essential part, and FIG. 3 is a graph showing the relationship between the amount of deviation between the induction electrode and the discharge electrode and the amount of ions output from the head, and FIG. 4 is a schematic cross-sectional view of the electrostatic recording head proposed previously. 1: Housing 2: Ceramic substrate 3: Chamber 4a: Induction electrode 5a: Discharge electrode
6: Insulating layer 7: AC power supply 11a: Control electrode 12: Passage
13b=control electrode 18.19: bias electrode 21: electrostatic recording medium 22: conductive layer 23
: Dielectric layer 24a: DC power supply A, B: Downstream end C: Air flow D: Discharge area P: Ion generation part Q: Control i11th Patent Applicant
Fuji Xerox Co., Ltd. Representative Masu Kobori (and 2 others) No. 15! I Figure 2

Claims (1)

[Claims] 1. In an electrostatic recording head that transports ions from an ion generating section by an air flow, the induction electrode and the discharge electrode are arranged with an insulating layer interposed therebetween, and the induction electrode is arranged downstream of the discharge electrode. An electrostatic recording head featuring: