JPH05104775A - Ion flow recording head - Google Patents

Abstract

PURPOSE:To form the proper electrostatic latent image corresponding to image data on a recording body by uniformizing the ion jet quantity in the longitudinal direction of an ion flow recording head by setting the length L of the ion flow path of the recording head to specific relation with respect to a set value L'. CONSTITUTION:An ion flow recording head is constituted of an ion supply means 1a almost uniformly blowing off ion flow from an ion jet orifice 11 opened along a longitudinal direction and an ion flow modulating means 1b forming the ion flow path 12 continued to the jet orifide 11 through the ion flow path 12 corresponding to image data. Then, the length L of the ion flow path is set so as to satisfy the relation of 0.8L'<=L<=1.2L' with respect to a set value L'. When recording images are formed by several kinds of recording heads wherein the length L of the flow path 12 is shifted from the set value L' stepwise and image qualities such as density irregularity, the reproducibility of a fine line or the contamination of a background part are evaluated, if the length L of the flow path 12 is within + or -10% of the set value L' (=200mum), sufficiently satisfactory image quality is obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ion current recording head for ejecting an ion current modulated according to image information to form an electrostatic latent image on a recording material such as a dielectric layer.

[0002]

2. Description of the Related Art Conventionally, as this type of ion flow recording head (hereinafter referred to as recording head), for example, one shown in FIG. 1 is known. Reference numeral 1a is an ion supply means for ejecting ions together with the air flow, and a corona discharge wire 15 connected to a high voltage DC power supply is stretched in an ion generation chamber 14 of a conductive housing 13 into which compressed air is introduced. Also, code 1b
Is an ion current modulation means for controlling the blowout of the ion current for each recording pixel, has a substrate 20 on which control electrodes 19 are arranged according to the pixel density, and the ion supply means 1a and the slit-like ion channel Are arranged to form twelve.

Extraction of ions from this recording head is specifically carried out as follows. First, a DC voltage of 2.0 to 6.0 KV is applied between the housing 13 and the corona discharge wire 15 to generate ions. A power supply (not shown) for ion extraction is provided between the housing 13 and the recording body (not shown).
Since the compressed air is introduced into the ion generation chamber 14, the generated ions are stored in the housing 13
It is accelerated by the electric field formed between the recording medium and the recording medium and the air flow inside the ion generation chamber 14, and is discharged from the ion ejection port 11 to the ion flow path 12. A control power supply 21 that outputs a high-potential or low-potential pulse signal according to image information is connected to each control electrode 19 of the ion flow modulation means 1b, and the control electrodes 19 that face each other across the ion channel 12 are provided. And housing 13
An electric field corresponding to the image information is formed between and. For this reason,
Ions flowing into the ion channel 12 flow toward the recording medium together with the air flow when the potential of the control electrode 19 is maintained at a low potential and the same potential as the potential of the housing 13 is maintained, When the potential of the control electrode 19 is maintained at a high potential, the electric field formed between the control electrode 19 and the housing 13 prevents the outflow to the recording medium. By the above operation, in the conventional recording head, the ion flow modulated according to the image signal is ejected from the ion flow path, and the electrostatic latent image can be formed on the recording medium.

[0004]

By the way, in this type of recording head, it is important that the ejection amount of ions is uniform along the longitudinal direction of the head. If it is not uniform, potential unevenness occurs in the electrostatic latent image formed on the recording medium, and the recorded image obtained by developing this electrostatic latent image has density unevenness and background stains. is there.

Generally, the amount of ions ejected from the recording head onto the recording medium can be adjusted by changing the voltage of the ion extracting power source, the voltage applied to the corona discharge wire and the amount of air introduced into the ion generating chamber. Is understood. However, since all of these parameters are changed to adjust the ion amount in the entire recording width along the longitudinal direction of the recording head, the density of the recorded image and the stain on the background portion change in the entire recording width, As a result, it was impossible to eliminate partial density unevenness and background stains.

The present invention has been made in view of the above object, and an object of the present invention is to make uniform the ion ejection amount along the longitudinal direction of the recording head and to form a proper electrostatic latent image corresponding to image information. An object is to provide an ion flow recording head that can be formed on a recording body.

[0007]

As a result of repeated studies by the inventors of the present invention in order to achieve the above object, attention is paid to the shape and size of the ion flow path through which the ions ejected from the ion supply means pass. Arrived Below, the shape of this ion channel,
The size will be described in detail with reference to FIG. In determining the size and shape of the ion channel 12, the length L and width W of the ion channel 12 are important. As described above, the extraction or damming of the ion flow in each pixel is controlled by the presence or absence of electrolysis between the control electrode 19 and the housing 13. That is, when an electric field is formed between the control electrode 19 and the housing 13, the ions moving in the ion flow path 12 reach the surface of the control electrode 19 or the housing 13 by the Coulomb force received from the electric field, and the ions flow. It does not spill out of Road 12. Therefore, in order to efficiently take out ions from the recording head 1 or completely block ejection of ions from the recording head 1, the voltage applied to the corona discharge wire 15, the amount of air introduced into the ion generation chamber 14,
The length of the ion channel 12 along with the voltage applied to the control electrode 19
L and width W must be carefully determined.

FIG. 2 shows that the voltage V _c applied to the corona discharge wire and the amount of air introduced into the ion generation chamber are constant, the potential of the control electrode 42 is kept at the same potential as the housing, and the width W of the ion flow channel is 100 μm. 7 is a graph showing the relationship between the length L of the ion flow path and the amount of ejected ions when the ion flow rate is fixed to 1. As is clear from this graph, the amount of ejected ions depends on the length L of the ion channel. Therefore, in order to obtain a desired ion ejection amount, it is important to accurately determine the length L of the ion channel based on FIG. However, in an electrostatic recording device using this type of recording head, in order to obtain a good recorded image without density unevenness and background stains, it is sufficient to keep the fluctuation range of the ion ejection amount within ± 10%. If the length L of the ion channel is adjusted correspondingly, it is considered that there will be no practical problem. For example, the length of the ion channel
When the design value of L is 150 μm, a good recorded image can be obtained if the length L is adjusted to be within 150 ± 30 μm over the entire area of the recording head in the longitudinal direction. Not limited to the example of FIG. 2, the following is a generalization of this condition. That is, regardless of the applied voltage Vc of the corona discharge wire, the amount of air introduced into the ion generation chamber, the width W of the ion flow path, etc., the length L of the ion flow path is within ± 20% of the design value L '. If so, it can be said that a stable and good recorded image can always be obtained.

That is, the ion recording head of the present invention has been devised based on such a study, and has an ion generation source inside and accelerates the generated ions to eject the ion flow. Means and an ion flow modulation means for forming an ion flow path communicating with the ion flow outlet of the ion supply means and controlling the ejection of the ion flow from the ion flow path in accordance with image information In the flow recording head, the length L of the ion flow path satisfies the relation 0.8L'≤L≤1.2L 'with respect to the design value L'.

[0010]

The above technical means operates as follows. Length of the ion flow path communicating from the ion ejection port of the ion supply means
By keeping L within ± 20% of the design value L ′, the fluctuation range of the amount of ions ejected from the recording head is ± 10% over the entire recording width.
A proper electrostatic latent image corresponding to image information can be formed on the recording medium.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The ion flow recording head of the present invention will be described in detail below with reference to the accompanying drawings. The schematic structure of the ion flow recording head according to the first embodiment of the present invention is substantially the same as that of the conventional recording head 1 shown in FIG. That is, there is an ion ejection port 11 opened along the longitudinal direction (the direction perpendicular to the paper surface of FIG. 1), an ion supply means 1a for ejecting an ion flow from this ion ejection port 11 substantially uniformly, and the ion ejection port. An ion flow channel 12 communicating with the ion flow channel 11 is formed, and the ion flow modulation means 1b is configured to modulate the ions passing through the ion flow channel 12 according to image information.

First, as shown in FIG. 3, the ion supply means 1a stretches a corona discharge wire 15 inside an ion generation chamber 14 formed in an aluminum housing 13 and connects the corona discharge wire 15 to the corona discharge wire 15. A high voltage DC power supply 16 for ion generation is connected. The recording body 2 on which an electrostatic latent image is written by the recording head 1 and the housing 1
The housing 1 is connected to a by the ion extraction power supply 21.
An electric field is formed from 3 toward the recording body 2, and the ions generated in the ion generation chamber 14 are ejected from the ion ejection port 11 to the outside of the housing 13 by the Coulomb force. In addition, an introduction hole 17 for compressed air is provided in the ion generation chamber 14 so as to face the ion ejection port 11, and the ion generation chamber 14 is provided.
The ions inside are ejected from the ion ejection port 11 with the assistance of the air flow in addition to the Coulomb force. Incidentally, reference numeral 18 in FIG.
Is a blower fan that sends compressed air into the introduction hole 17.

The ion flow modulating means 1b includes an insulating substrate 20 made of glass in which a plurality of control electrodes 19 are arranged along the main scanning direction according to the pixel density, and the control electrodes according to image information. A control power source 21 for inputting a pulse signal to 19 and holding the control electrode 19 at a high potential or a low potential. The insulating substrate 20 is arranged so as to form an ion flow path 12 communicating with the housing 13 together with the ion ejection port 11, and the ion flow discharged from the ion supply means 1a is the ion flow path 12 And ejected from the recording head 1. still,
Regarding the operation in which the ion current is modulated according to the image information,
The description is omitted here because it is similar to the conventional technique.

The insulating substrate 20 of the ion current modulating means is attached to the housing 13 via an insulating spacer 22. In this embodiment, the design value of the length of the ion channel 12 is L '= 20.
0 μm, and the length L of the ion channel 12 in each recording pixel is 1
The insulating substrate 20 was attached so as to be in the range of 90 to 210 μm. At this time, in order to accurately and easily set the length L of the ion channel 12, as shown in FIG.
Resin block 2 having positioning protrusions 23 at both ends of 3
4 is arranged, and the end face of the insulating substrate 2020 is abutted against the positioning protrusion 23 to dispose the substrate. As a result, the insulating substrate 20 can be easily and accurately attached, and the desired length L of the ion channel 12 can be obtained. In addition, the length L of the ion channel 12 is
The back side of the insulating substrate 20 was urged toward the housing 13 by the pressing plate 25 so that the ion amount would not fluctuate due to the deviation. As a result, the amount of ions ejected from the ion flow path 12 is in the range of 68 to 72 nA / cm even when measured at any portion along the longitudinal direction of the recording head 1, and within ± 10% of the target ion amount. Fit in.

FIG. 5 shows an example of an electrostatic recording apparatus constructed by using the recording head 1 described above. In general, a developer carrying member (recording member) 2 which rotates in a direction of an arrow at a predetermined speed is shown. A developing device 4 for forming a thin layer of the developer 3 on the surface thereof, a recording head 1 for forming an electrostatic latent image according to image information on the developer carrier 2, and the developer carrier It is composed of a transfer electrode 5 facing the body 2 with a predetermined space, and a fixing device 6 having a heat roller 6a.

In the developing device 4, a hopper 31 is arranged on the back side of the developer carrier 2 made of an aluminum roll, and the other end of the layer forming member 32 whose one end is fixed to the hopper 31 is the developer. The developer 3 held in contact with the carrier 2 has a thin layer of the developer 3 contained in the hopper 31 continuously and uniformly on the surface of the developer carrier 2 as the developer carrier 2 rotates. It has been adapted. The layer forming member 32 is formed by adhering a silicone rubber 34 to the tip of a stainless steel support 33, and the silicon rubber 34 contacts the developer carrier 2 with a predetermined pressing force based on the elastic force of the support 33. In contact with each other, the developer 3 is thinned to a uniform thickness and is triboelectrically charged. Here, the developer 3 is a non-magnetic one-component developer made of an insulating toner, and when formed into a thin layer on the surface of the developer carrier 2, -30
It is charged to ~ -70V. Reference numeral 35 is a transport roll for adhering the developer 3 in the hopper 31 to the developer carrier 2, and reference numeral 36 is a seal member for sealing between the developer carrier 2 and the hopper 31.

The recording head 1 has an ion channel 12
The insulating substrate 20 is arranged so as to blow the ion stream ejected from the developer carrier 2 onto the developer carrier 2.
2 and 0.02 to 5 mm apart, more preferably 0.1 to 3 mm
Holds the interval.

On the other hand, the transfer electrode 5 is a rod-shaped electrode arranged along the longitudinal direction of the developer carrier 2 and faces the developer carrier 2 with a predetermined space. Further, a transfer electric field is formed between the transfer electrode 5 and the developer carrier 2 so as to attract only the developer 3 charged to a specific potential from the developer carrier 2 side to the transfer electrode 5 side. ..

In the electrostatic recording apparatus constructed as described above, image formation is performed on the recording sheet 7 as follows. First, the developer carrier 2 rotates to form a thin layer of developer on the surface thereof, and in synchronization with this timing, an ion current modulated according to image information is carried from the recording head 1 The electrostatic latent image is written in a thin developer layer covering the developer carrier 2 by being ejected toward the body 2. On the other hand, after the recording sheet 7 is carried out from a storage tray (not shown), it is sent between the transfer electrode 5 and the developer carrier 2 at a predetermined timing synchronized with the writing of the electrostatic latent image by the registration roll 8. .. Since a transfer electric field is formed between the transfer electrode 5 and the developer carrier 2, the developer 3 corresponding to the electrostatic latent image is given sufficient energy for flight by the transfer electric field, and the transfer electrode 5 Recording sheet 7 passing in front of
An unfixed visible image is formed on. After that, the recording sheet 7 is sent to the fixing device 6, and the unfixed visible image is heated and fixed, and a series of image forming operations is completed.

In order to test the performance of the recording head 1 of this embodiment, an image was actually formed by using this electrostatic recording device. As a result, the formed recorded image was found to have density unevenness and background stains. However, it was confirmed that the amount of ions ejected from the recording head 1 was substantially uniform along the longitudinal direction of the recording head 1.

Next, the inventors of the present invention will explain the length of the ion channel 12.
A recording image was formed by using several kinds of recording heads in which L was gradually shifted from the design value L ', and the quality of the image such as density unevenness, reproducibility of fine lines, and background stain was evaluated in three stages. Table 1 shows the results. As is clear from this result, the length L of the ion channel 12 is ± 10% of the design value L ′ (= 200 μm).
If it is within the range, a satisfactory image quality can be obtained.
Even within 20%, image quality with no practical problems was obtained.
This confirmed the effectiveness of the present invention.

[0022]

[Table 1]

[0023]

As described above, according to the ion flow recording head of the present invention, the length L of the ion flow path communicating from the ion ejection port of the ion supply means is designed over the entire area in the longitudinal direction of the recording head. By keeping it within ± 20% of the value L ′, it is possible to suppress the fluctuation of the ion ejection amount along the longitudinal direction of this recording head and form an appropriate electrostatic latent image corresponding to the image information on the recording medium. It becomes possible to do.

[Brief description of drawings]

FIG. 1 is a sectional view showing an ion flow recording head to which the present invention is applied.

FIG. 2 is a graph showing the relationship between the length L of the ion flow path and the amount of ejected ions from the ion flow recording head.

FIG. 3 is a perspective view showing an ion flow recording head according to a first embodiment.

FIG. 4 is a main part perspective view showing an engaged state of the insulating substrate and the housing according to the first embodiment.

FIG. 5 is a schematic diagram showing an electrostatic recording apparatus configured using the ion flow recording head according to the first embodiment.

[Explanation of symbols]

1 ... Ion flow recording head, 1a ... Ion supply means, 1b ... Ion flow modulation means, 11 ... Ion jet outlet, 12 ... Ion flow path

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[Procedure amendment]

[Submission date] December 3, 1991

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0007

[Correction method] Change

[Correction content]

[0007]

As a result of repeated studies by the inventors of the present invention in order to achieve the above object, attention is paid to the shape and size of the ion flow path through which the ions ejected from the ion supply means pass. Arrived Below, the shape of this ion channel,
The size will be described in detail with reference to FIG. In determining the size and shape of the ion channel 12, the length L and width W of the ion channel 12 are important. As noted above, extraction or damming the ion current in each pixel is controlled by the presence or absence of electric field between the control electrode 19 and the housing 13. That is, when an electric field is formed between the control electrode 19 and the housing 13, the ion flow path 12
The ions moving through reach the surface of the control electrode 19 or the housing 13 by the Coulomb force received from the electric field, and are not ejected from the ion channel 12 to the outside.
Therefore, the ions are efficiently extracted from the recording head 1,
Alternatively, in order to completely block the ejection of ions from the recording head 1, the voltage applied to the corona discharge wire 15, the amount of air introduced into the ion generation chamber 14, the voltage applied to the control electrode 19, and the like, along with the ion flow path 12 are used. The length L and width W must be carefully determined.

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0008

[Correction method] Change

[Correction content]

FIG. 2 shows that the applied voltage V _c of the corona discharge wire and the amount of air introduced into the ion generation chamber are constant, and
6 is a graph showing the relationship between the length L of the ion flow path and the amount of ejected ions when the potential of the control electrode 19 is kept at the same potential as the housing and the width W of the ion flow path is fixed at 100 μm. As is clear from this graph, the amount of ejected ions depends on the length L of the ion flow path. Therefore, in order to obtain a desired amount of ejected ions, it is important to accurately determine the length L of the ion channel based on FIG. However, in order to obtain a good recorded image without density unevenness and background stain in an electrostatic recording device using this type of recording head,
Since it suffices to limit the fluctuation range of the amount of ejected ions to within ± 10%, it is considered that there is no practical problem if the length L of the ion flow path is adjusted correspondingly. For example,
When the design value of the length L of the ion channel is 150 μm,
This length L is 15 over the entire length of the recording head in the longitudinal direction.
If it is adjusted to be within 0 ± 30 μm, a good recorded image can be obtained. Not limited to the example of FIG. 2, the following is a generalization of this condition. That is,
Regardless of the applied voltage Vc of the corona discharge wire, the amount of air introduced into the ion generation chamber, the width W of the ion flow path, etc., the length L of the ion flow path should be within ± 20% of the design value L ′. Therefore, it can be said that a stable and good recorded image can always be obtained.

[Procedure 3]

[Document name to be amended] Statement

[Correction target item name] 0012

[Correction method] Change

[Correction content]

First, as shown in FIG. 3, the ion supplying means 1a stretches a corona discharge wire 15 inside an ion generation chamber 14 formed in an aluminum housing 13 and also connects the corona discharge wire 15 to the corona discharge wire 15. A high voltage DC power supply 16 for ion generation is connected. An electric field from the housing 13 to the recording body 2 is formed by the ion extracting power supply 26 between the recording body 2 on which the electrostatic latent image is written by the recording head 1 and the housing 1a, and the ion generating chamber 14 is formed. Ions generated in the housing 1 from the ion ejection port 11 by Coulomb force.
3 is discharged to the outside. In addition, a compressed air introduction hole 17 is provided in the ion generation chamber 14 so as to face the ion ejection port 11.
Is opened, and the ions in the ion generation chamber 14 are supported by the air flow in addition to the Coulomb force, and the ion ejection port 1
Emitted from 1. Reference numeral 18 in FIG. 1 is a blower fan that sends compressed air into the introduction hole 17.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0014

[Correction method] Change

[Correction content]

The insulating substrate 20 of the ion current modulating means is attached to the housing 13 via an insulating spacer 22, but in the present embodiment, it covers the entire recording width of the recording head 1.
In order to extract an ion amount of 70 nA / cm, the design value of the length of the ion flow channel 12 is set to L ′ = 200 μm, and the length L of the ion flow channel 12 in each recording pixel is 190 to 21.
The insulating substrate 20 was attached so that the range was 0 μm. At this time, in order to accurately and easily set the length L of the ion flow channel 12, as shown in FIG. 4, resin blocks 24 having positioning protrusions 23 are provided at both ends of the housing 13, and Insulating substrate 2 on positioning protrusion 23
The end face of 0 was abutted to arrange the substrate. As a result, the insulating substrate 20 can be easily and accurately attached, and the desired length L of the ion flow channel 12 can be obtained. Further, the back side of the insulating substrate 20 is urged toward the housing 13 by the pressing plate 25 so that the length L of the ion flow path 12 does not change due to mechanical vibration or the like and the amount of ions does not fluctuate. As a result, the amount of ions ejected from the ion flow path 12 is in the range of 68 to 72 nA / cm even if measured at any portion along the longitudinal direction of the recording head 1, and the target amount of ions (70 nA / cm) is obtained. Within ± 10% of The width W of the ion outlet 12
Is determined by the thickness of the spacer 20, but in this embodiment
Then, W = 100 μm. Also, corona discharge wire 1
The voltage applied to 5 was 3.4 kV, and the ion generation chamber 1
The air pressure introduced into 4 is about 100 mmH ₂ O.

[Procedure Amendment 5]

[Document name to be amended] Statement

[Correction target item name] 0016

[Correction method] Change

[Correction content]

In the developing device 4, a hopper 31 is arranged on the back side of the developer carrying member 2 made of an aluminum roll, and the other end of the layer forming member 32 whose one end is fixed to the hopper 31 is the developer. Which is brought into contact with the carrier 2,
The developer 3 contained in the hopper 31 is continuously and uniformly thinned on the surface of the developer carrier 2 as the developer carrier 2 rotates. The layer forming member 32 is formed by adhering a silicon rubber 34 to the tip of a stainless steel support 33.
The developer bearing member 2 is brought into contact with the developer bearing member 2 with a predetermined pressing force based on the elastic force of the developer 3, and the developer 3 is thinned to a uniform thickness and frictionally charged. Here, the developer 3 is a non-magnetic one-component developer made of insulating toner, and is charged to about −30 V when it is thinned on the surface of the developer carrier 2. still,
Reference numeral 35 is a transport roll that adheres the developer 3 in the hopper 31 to the developer carrier 2, and reference numeral 36 is a seal member that seals between the developer carrier 2 and the hopper 31.

[Procedure correction 6]

[Document name to be corrected] Drawing

[Name of item to be corrected] Figure 3

[Correction method] Change

[Correction content]

[Figure 3]

[Procedure Amendment 7]

[Document name to be corrected] Drawing

[Name of item to be corrected] Figure 5

[Correction method] Change

[Correction content]

[Figure 5]

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kyoji Suwabe 2274 Hongo, Ebina City, Kanagawa Prefecture, Fuji Zero Tux Co., Ltd.Ebina business office (72) Keiichi Yagi 2274 Hongo, Ebina City, Kanagawa Prefecture, Fuji Zero Tux Co., Ltd. Ebina Office

Claims (1)

[Claims] 1. An ion supply means which has an ion generation source inside thereof and accelerates the generated ions to eject an ion flow.
An ion flow recording head comprising an ion flow modulation means for forming an ion flow path communicating with the ion flow ejection port of the ion supply means and controlling ejection of the ion flow from the ion flow path according to image information. 2. The ion flow recording head according to, wherein the length L of the ion flow path satisfies the relationship of 0.8 L'≤L≤1.2 L'with respect to the design value L '.