JPH04216076A - Electrostatic recorder - Google Patents

Abstract

PURPOSE:To stably carry a uniformly dissolved developer to an opposed part of a recording electrode to a counter electrode, ensure the prevention of the missing of an image and the deterioration of an image density caused by the cohesion of the developer, and obtain a high-resolution and high-quality record ing image for a long term without applying the developer to the electrodes. CONSTITUTION:On an upstream of a recording part W in which a plurality of electrodes EL are juxtaposed in the width direction of a carry path of a magnetic toner (d) so as to be opposed to a cylindrical electrode 5, a plurality of disturbance electrodes EA are similarly juxtaposed in the width direction of the carry path of the magnetic toner (d). Alternative voltages shifted in phase are separately applied to the disturbance electrodes EA adjacent to each other from an alternative power source Q, whereby an electric field moving in the juxtaposing direction of the disturbance electrodes EA is formed.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a non-contact electrostatic recording device that forms an electrostatically recorded image without bringing a recording head into contact with a recording medium.

0002

BACKGROUND OF THE INVENTION Conventionally, a multi-stylus printer is well known as one of electrostatic recording devices. This multi-stylus printer constructs a recording head by arranging a large number of needle-like electrodes (stylus) at minutely even intervals in the main scanning direction, and selectively applies voltage to each needle-like electrode according to the recording signal to print on the paper. An electrostatic latent image is formed by directly discharging the electrostatic latent image. In this case, special paper coated with a high electrical resistance agent is used so that charges can be easily and stably retained on the paper. However, such special paper is not preferred as paper for office use because it is difficult to write on with a pencil or pen, and its quality deteriorates depending on environmental conditions such as humidity, so there are problems with storage stability.

Furthermore, if the distance between the tip of the acicular electrode and the paper surface is large, the discharge electric field will spread and the formed dots will become large, making it difficult to obtain a high-resolution recorded image. For that reason,
A minute gap is secured by providing a gap material on the surface of the paper and bringing the tip of the needle electrode into sliding contact with the gap material. However, when using this method, there is a problem that the tip of the needle electrode is worn out.

[0004] Therefore, as an electrostatic recording method that can use plain paper and accurately ensure a minute distance between the image medium and the tip of the recording electrode, a toner image is formed on a drum-shaped intermediate recording medium. A method is used in which the toner image is transferred onto paper. In this method, the use of an intermediate recording medium tends to increase the size of the apparatus, so a process in which recording and development are performed simultaneously is usually adopted to avoid increasing the size of the apparatus. In this case, the recording electrodes are installed in parallel in the width direction (main scanning direction) of the developer transport path, and the developer is selectively transferred from the recording electrodes to the surface of the counter electrode, which also serves as an intermediate recording medium, according to the recording information, and the toner is form an image.

However, in the above-mentioned method, the developer that has been transported tends to stagnate on the upstream side of the electrode facing portion where the recording electrode and the facing electrode face each other with a small distance between them. The stagnant developer may aggregate, or the aggregated developer may be compacted in the area facing the electrode and adhere to the recording electrode, which not only reduces image resolution but also reduces image density and This results in a significant drop in image quality.

[0006]

OBJECT OF THE INVENTION The present invention was made in view of the problems of the prior art described above, and it is possible to reliably prevent developer from coagulating and adhering to electrodes, and to maintain high-resolution, high-quality recorded images over a long period of time. An object of the present invention is to provide an electrostatic recording device that can be stably formed over a long period of time.

[0007]

SUMMARY OF THE INVENTION In order to achieve the above-mentioned object, the present invention includes a developer conveying means for conveying the developer along a predetermined developer conveying path, and a developer conveying means perpendicular to the developer conveying direction. A plurality of recording electrodes are arranged in parallel at intervals in the width direction of the recording electrode, and a counter electrode is arranged with a required gap from the recording electrodes, and a voltage is applied to each of the recording electrodes according to recorded information. In the electrostatic recording device that selectively transfers the developer transported along the developer transport path to the counter electrode side, a plurality of disturbances that move the developer in a direction different from the developer transport direction. Electrodes are arranged in parallel near the upstream side of the recording electrode with respect to the direction in which the developer is conveyed, and a voltage is applied to each of the disturbance electrodes so as to form an electric field that moves along the direction in which the electrodes are arranged. The main point is to cause disturbance.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be specifically explained below based on the embodiments shown in FIGS. 1 to 13.

FIG. 1 is a schematic sectional view showing the overall configuration of a recording apparatus as an embodiment of the present invention. In the same figure,
Reference numeral 1 denotes a paper feed cassette loaded with plain paper P, which is detachably attached to the side of the machine. A paper feed roller 1a is disposed above the tip of the inserted paper feed cassette 1 so as to be rotatable in the direction of the arrow. In front of the paper feed roller 1a, upper and lower conveyance guide plates 2a and 2b made of insulating members are laid to form a paper transport path. A pair of standby rolls 3 is disposed in this paper feed path, and after temporarily stopping the advance of the paper P fed out by the paper feed roller 1a and adjusting the conveyance posture, the paper P is transferred to the image transfer section T on the downstream side. The image is re-fed in synchronization with the arrival timing of the recorded image, which will be described later.

In the image transfer section T on the downstream side of the standby roll pair 3, a transfer charger 4 is arranged opposite to a cylindrical electrode 5 which also serves as an image carrier. In this example, the cylindrical electrode 5 is driven and rotated in the counterclockwise direction indicated by arrow A. On the opposite circumferential surface of the cylindrical electrode 5, a recording image forming unit U, which will be described later, is arranged to face the cylindrical electrode 5. By this recording image forming unit U, the cylindrical electrode 5
A toner recorded image is formed on the surface, and as the cylindrical electrode 5 rotates, the toner recorded image is conveyed to the image transfer section T and transferred onto the paper that is being fed again. The configuration of the recorded image forming unit U will be explained in detail later.

On the downstream side of the image transfer section T, a separating claw 6 is provided with its tip pressed against the circumferential surface of the cylindrical electrode. and,
On the downstream side of the separation claw 6, an air suction type conveyor belt 7 is stretched horizontally, and after the recorded image has been transferred, the back side of the paper separated from the circumferential surface of the cylindrical electrode 5 is suctioned by the separation claw 6. The fixing device 8 installed in front of the
Transport towards. The fixing device 8 consists of a heating roll 8a and a pressure roll 8b, and thermally fixes the toner image when the paper is held between the two rolls and conveyed. After the fixing, the sheets are discharged from the discharge port 9 and stacked on the paper discharge tray 10 in a face-down state with the image side facing down.

As described above, in the recording apparatus of this example,
Since the entire paper transport path from paper feeding to paper ejection is formed in a substantially straight shape, the paper passing operation is generally smooth, and paper passing defects such as image defects and paper jams are less likely to occur. It also has the advantage that the above-mentioned straight sheet passing path can achieve a face-down sheet discharge state that does not require page alignment, which is preferable for the recording apparatus.

The detailed structure of the recording image forming unit U will now be explained.

As shown in FIG. 2, the recorded image forming unit U is roughly composed of a development recording tank 12 equipped with a recording means and a developer conveying means, and a developer storage tank 11 storing developer for replenishment. . In the developer storage tank 11, a stirring blade 11a is rotatably disposed. In this example, an insulating magnetic toner is used as the developer, which is a one-component developer containing at least an insulating resin, a magnetic fine powder, and colorant particles, and has a negative (-) friction charge polarity.

A horizontal developer circulation path 13 shown in FIG. 3 is formed at the bottom of the development recording tank 12. As shown in FIG. In FIG. 3, in a pair of parallel longitudinal paths 13a, 13b in this horizontal circulation path 13, a pair of auger rolls 14a, 1
4b is rotatably installed. Each auger roll 14a
, 14b have a plurality of spiral blades 14a2, 14b2 erected on the circumferential surface of each shaft 14a1, 14b1, and reverse feed blades 14a3, 14b3 with opposite helical directions are erected at one end of each (Fig. 4). Then, each auger roll 14a, 14b is moved along the longitudinal path 13a so that the respective reverse feed blades 14a3, 14b3 are located on opposite sides of each other.
, 13b, respectively. These pair of auger rolls 14a and 14b are driven to rotate in opposite directions to each other and in a direction that conveys the developer toward the reverse feed blades 14a3 and 14b3, as shown by arrows B and C. As a result, at each corner portion where the reverse feed blades 14a3 and 14b3 are provided, conveyance forces in opposite directions collide with each other, and the magnetic toner is ejected in the right angle direction and flows toward the other longitudinal path. In this manner, in this example, the magnetic toner is stirred and circulated in the direction shown by the broken arrow D, and at this time, the magnetic toner can be sufficiently triboelectrically charged. In addition, Augarol 14a
, 14b, it is possible to triboelectrically charge the developer to a sufficient amount by changing the material and shape of the developer.

The center of the horizontal circulation path 13 constructed as described above is surrounded by a wall S to prevent the circulating developer from entering.
A space S surrounded by w is formed. As shown in FIG. 2, the auger roll 14 closer to the developer storage tank 11
A replenishment port 11b for replenishing magnetic toner d0 is provided above the auger roll 14a along the axial direction of the auger roll 14a.

A developing sleeve 15 for vertically conveying the developer is installed horizontally above the other auger roll 14b. The developing sleeve 15 has a magnet roll 16 rotatably built therein, and has the above-mentioned cylindrical electrode 5.
are placed facing each other. Different magnetic poles are alternately magnetized on the circumferential surface of the magnet roll 16, and by driving and rotating the magnet roll 16 in the counterclockwise direction shown by arrow H, the magnetic toner d is spread along the circumferential surface of the developing sleeve 15. and transport it in the clockwise direction shown by the dashed arrow.

Near the circumferential surface of the developing sleeve 15, which serves as a developer conveyance path, on the upstream side in the developer conveyance direction, there is a doctor blade 1 for regulating the layer thickness of the magnetic toner d to an appropriate thickness.
2a is installed. Further, a toner scattering prevention plate 12b is provided above the doctor blade 12a. The toner scattering prevention plate 12b is provided to prevent the developer transported downstream under the layer thickness regulation by the doctor blade 12a from scattering outside the recording image forming unit U and staining the image. In this example, the upper end of the tank wall of the developing and recording tank 12 is bifurcated, and one side is formed as a doctor blade 12a and the other side is formed as a toner scattering prevention plate 12b.

On the downstream side of the above-mentioned toner layer thickness regulating section with respect to the toner transport direction, a recording section W for forming a toner recorded image on the circumferential surface of the cylindrical electrode 5 is constructed as follows.

A recording electrode sheet 17 provided with a large number of recording electrodes is provided in an area on the upstream side of the circumferential surface of the developing sleeve 15 from the position closest to the circumferential surface of the cylindrical electrode 5 (in this example, the left half circumferential surface in the figure). It has been covered. As shown in FIG. 4, the recording electrode sheet 17 has a large number of recording electrode wires 17a extending parallel to each other in the longitudinal direction of the sheet along the circumferential direction of the circumferential surface of the developing sleeve 15, and arranged at a predetermined fine pitch. They are arranged in parallel in the width direction (toner conveyance path width direction: main scanning direction). The number of recording electrode lines 17a is made to correspond to the maximum number of data for one main scanning line. The recording electrode sheet 17 of this example is made of a flexible printed circuit board (FPC), and includes recording electrode wires 17a made of a large number of non-magnetic conductive materials.
40 on the base film 17b made of a flexible insulating material.
84.6μm pitch (300DPI) with μm gap maintained.
) is patterned with a density of The surface of the recording electrode sheet 17 is coated with an insulating coat 17c. This ensures the insulation between each recording electrode wire 17a, and also prevents the recording electrode wire 17a from being damaged by friction with the magnetic toner.
can prevent wear.

FIG. 5 is a schematic cross-sectional view showing the structure of the recording section W and its surroundings. In the figure, recording electrode line 17a
The tip portion is slightly raised and exposed on the surface of the insulating coat 17c. The exposed tip of the recording electrode line 17a becomes the recording electrode EL that substantially performs the recording operation.

As shown in FIG. 4, a large number of disturbance electrodes EA made of a non-magnetic conductive material are arranged on the surface of the recording electrode sheet 17 at a position a suitable distance away from the recording electrode EL toward the upstream side. They are arranged in parallel along the EL row. This disturbance electrode EA is provided to move the developer also in the width direction of the developing sleeve 15 so that the developer does not stay and aggregate on the upstream side of the recording section W where the passage cross section is narrow. Disturbing electrode E in this example
As shown in the plan view of FIG. 6 and the cross-sectional view of FIG. It is extended to the side. The installation pattern of the disturbance electrode EA is shown in Figure 6.
In addition to the pattern in which electrodes of the same shape are laid at equal intervals across the entire width direction as shown in FIG.
They may be laid in a line-symmetrical pattern on both sides with the center line a of the developer transport path as the axis of symmetry. Furthermore, it is not always necessary to have the recording electrode EL and the disturbance electrode EA in a 1:1 correspondence.

The disturbance electrodes EA arranged as described above are divided into N appropriate groups. In that case, X-X in Figure 5
As shown in FIG. 10, which is a line cross-sectional view, from the center in the width direction of the surface of the recording electrode sheet 17, which serves as the developer transport path, to both sides (
N-1) Every other disturbance electrode EA is made into the same group and divided into N groups. Then, AC voltages having a phase shift of 2π/N are applied to each set. In this example, the disturbance electrodes EA are divided into three groups, and the disturbance electrodes EA1, EA4,..., EA1'
, EA4'..., a set of disturbance electrodes EA2, EA2',...
are set as one set, and disturbance electrodes EA3, EA3', .

When the application of AC voltage to each disturbance electrode EA is started, a voltage between EA2 and EA is applied between the neighboring disturbance electrodes EA1 and EA2 when V1<V2 (instantaneous voltage).
An electric field towards 1 is formed. The same electric field is formed between adjacent disturbance electrodes EA2 and EA3 faster by 1/3 period. That is, a wave-shaped AC electric field is formed that advances toward the center along the direction in which the disturbance electrodes EA are arranged. A similar traveling wave electric field is also formed in the disturbance electrodes EA' and the like arranged on the opposite side. Therefore, an electric field is formed that advances symmetrically from both sides of the developer transport path to the center, and the electric field force acts on the negatively charged magnetic toner in the opposite direction to the electric field. Attempts are made to move the magnetic toner in directions α and β opposite to the traveling direction of the magnetic toner. In this way, the magnetic toner is not only affected by the conveyance force along the circumferential direction of the developing sleeve 15 by the magnet roll 16 shown in FIG. Force also comes into play. As a result, in FIG. 5, in the region R where the developer is likely to accumulate on the upstream side of the recording section W (hereinafter referred to as the developer retention region), the magnetic toner d whose conveying force is weakened is transferred in the width direction of the circumferential surface of the developing sleeve 15. can be moved efficiently to prevent agglomeration. Also, due to the movement of the magnetic toner d in the width direction, the recording electrode sheet 1
7 surface (insulating coat 17c surface) is also prevented from adhering to the magnetic toner. Therefore, as will be described later, it is possible to stably form a high-quality recorded image with high resolution and no reduction in image density or image loss.

In FIG. 2, on the downstream side of the recording unit W in the toner conveying direction, there is a wall Sw1 on the developer storage tank 11 side that surrounds the central space S of the horizontal circulation path 13 described above.
is extended, and its tip is brought into contact with the circumferential surface of the developing sleeve 15. As a result, the magnetic toner d', which is not transferred in the recording section W but remains on the circumferential surface of the developing sleeve 15 and is conveyed with the rotation of the magnet roll 16, is transferred to the horizontal circulation path 1.
The magnetic toner d is scraped onto the replenishment tank side path 13a of No.3.
This prevents the inconvenience of intruding into the central space S or being directly returned to the upstream side along the circumferential surface of the developing sleeve 15 without passing through the horizontal circulation path 13. Note that a dedicated flat plate member for scraping off the residual magnetic toner d' adhering to the developing sleeve 15 may be provided separately from the peripheral wall of the central space S. In this case, the scraping member may be supported in the vertical direction, its tip abutted on the circumferential surface of the developing sleeve 15, and its other end extended to the bottom of the central space S. Furthermore, if the scraping member is made of a magnetic material, the magnetic force of the magnet roll 16 can be blocked, and a smoother scraping and return effect can be obtained.

The recording electrode sheet 17, which has been laid out over about half of the circumferential surface of the developing sleeve 15 as described above, is pulled out in the horizontal direction and then lowered vertically, extending into the central space S of the horizontal circulation path described above. It has been set up. A plurality of drive circuit elements 18 are provided in the vertically extending portion of the recording electrode sheet 17 to apply a recording voltage to each recording electrode EL according to recording data.
It is equipped with. Then, as shown in FIG. 5, each drive circuit element 18 has the recording electrode line 1 of the recording electrode sheet 17
7a are divided into N pieces and connected to each other. Like this,
By storing and installing the other end of the recording electrode sheet 17 on which the drive circuit element 18 is mounted in the central space S, the drive circuit element 18 can be protected from dust such as developer, and the structure of the development recording tank 12 can be made conspicuous. It can be made more compact.

Next, the operation of forming a recorded image in the electrostatic recording apparatus of this example will be explained.

In FIG. 5, when the magnet roll 16 is driven and rotated in the direction of the arrow E, a rotating magnetic field is formed on the outer peripheral surface of the developing sleeve 15 that causes the particles of the magnetic toner d to rotate, and the magnetic toner d forms ears. While doing so, it is transported in the direction of the arrow opposite to the rotation direction of the magnet roll 16. The conveyed magnetic toner d is regulated to have a predetermined thickness by the doctor blade 12a, and then conveyed to the recording section W via the developer retention area R. When passing through the developer retention area R, an electric field force traveling in the width direction by the disturbance electrode EA acts on the magnetic toner d. As a result, a resultant force of the conveying force of the magnet roll 16 and the above-mentioned electric field force acts on the magnetic toner d, and the magnetic toner d advances obliquely on the circumferential surface of the developing sleeve 15. In the developer retention area R, the magnetic toner d is densely packed and movement in the circumferential direction is suppressed, so movement in the width direction becomes predominant. As a result, the magnetic toner particles arranged in the width direction are efficiently mixed with each other, and aggregation of the magnetic toner in the developer retention area R is reliably prevented.

In the recording section W, a large number of recording electrodes EL are arranged in parallel as shown in FIG. A drive circuit element 18 shown in FIG. 2 selectively applies a recording voltage to each recording electrode EL according to recording data. In this case, when one bit of recording data is, for example, "H", the corresponding recording electrode E
When a voltage of -200V is applied to L, the cylindrical electrode 5 facing the recording electrode EL is supplied with a voltage of -50V by the bias power supply 5a.
Since a voltage of V is applied, a potential difference of 150 V is formed from the cylindrical electrode 5 to the recording electrode EL. Because the negatively charged magnetic toner d moves toward the higher potential,
Only the magnetic toner d on the recording electrode EL to which a voltage of -200V is applied is selectively transferred to the surface of the cylindrical electrode 5, and 1
Form a black dot.

On the other hand, when the 1-bit recording data is "L", the recording electrode EL is at the ground potential. As a result, the potential difference seen from the cylindrical electrode 5 to its corresponding recording electrode EL is -50V.
Therefore, the negative polarity magnetic toner d remains held on the recording electrode EL side and does not transfer.

As described above, the potential of each recording electrode EL is selectively controlled to -200V and the ground potential according to the input recording data, and a toner recording image corresponding to the recording data is formed on the surface of the opposing cylindrical electrode 5. Ru. In this case, the magnetic toner d that has been uniformly dispersed by the disturbance electrode EA on the upstream side is smoothly transported to the recording section W. Therefore, image defects and variations in image density due to aggregation of magnetic toner do not occur, and magnetic toner does not adhere to the recording electrode EL, and a high-resolution, high-quality recorded image is stably formed.

Further, since the step G corresponding to the thickness of the recording electrode sheet 17 is formed immediately downstream of the recording section W, the magnetic toner d' remaining on the developing sleeve 15 without being used for image formation is removed. , immediately moves away from the surface of the cylindrical electrode 5 after passing through the recording section W. Therefore, the inconvenience that the toner recorded image formed on the surface of the cylindrical electrode 5 in the recording section W is disturbed due to mutual interference with the residual magnetic toner d' can be reliably avoided.

Furthermore, since the recording electrode EL is exposed without being coated with the insulating coat 17c, unnecessary charges are not accumulated on the recording electrode EL. Therefore, scumming caused by unnecessary charges and voltage leakage between the recording electrodes are prevented, and clear toner recorded images with high resolution and high density are stably formed.

In FIG. 1, the toner recorded image formed on the surface of the cylindrical electrode 5 is conveyed to the image transfer section T as the cylindrical electrode 5 rotates in the counterclockwise direction A, and here the timing is measured by the pair of standby rolls 3. The image is then transferred onto the paper that is re-fed. Incidentally, in order to adjust the density of the above-mentioned toner recorded image, it is sufficient to change the bias voltage of the bias power supply 5a. In that case, the appropriate adjustment range is about 0 to -50V, and the closer it is to 0V, the higher the image density becomes.

In FIG. 2, the magnetic toner d' remaining in the recording section W without being transferred to the cylindrical electrode 5 side moves downstream with the rotation of the magnet roll 16, and is removed from the surface of the developing sleeve 15 by the scraping wall Sw1. The toner is scraped off, falls onto the auger roll 14a, and is stirred and mixed with the magnetic toner d0 that is replenished from the replenishment port 11b.

As the auger roll 14a rotates, the fallen and returned residual magnetic toner d' and the replenishment magnetic toner d0 are mixed and stirred and circulated and conveyed. In FIG. 3, the magnetic toner that is circulated in the direction of the dashed arrow N is conveyed in the vertical direction again by the rotating magnetic field of the magnet roll 16 extending above it when being conveyed along the longitudinal path 13b on the anti-replenishment side. Ru.

As described above, in the recording section W, the cylindrical electrode 5
The residual magnetic toner d′ that was not transferred to the side but was transported downstream
is scraped onto the horizontal circulation path 13, and smoothly returned to the upstream side while being stirred through this horizontal circulation path 13,
The toner is used again to form a recorded image. In this case, the magnetic toner d before being conveyed in the vertical direction is
Since the developing sleeve 1 is being conveyed while being stirred along the axial direction (width direction of the toner conveying path: main scanning direction),
5. It is uniformly supplied over the entire width direction of the circumferential surface. Therefore, the magnetic toner d is always uniformly supported on the circumferential surface of the developing sleeve 15 over the entire width direction and is conveyed to the recording section W, thereby stably producing a high-quality recorded image with uniform image density as described above. It becomes possible to obtain Further, when the magnetic toner d is circulated and conveyed while being stirred in the horizontal circulation path 13, the magnetic toner particles rub against each other, and the magnetic toner is sufficiently triboelectrically charged.

The voltage application to the disturbance electrode EA is continued for an appropriate period of time even after the rotation of the magnet roll 16 is stopped when the electrostatic recording apparatus is stopped. Thereby, retention of the magnetic toner d in the developer retention area R can be eliminated. Therefore, it is possible to prevent the inconvenience that the staying magnetic toner aggregates while the operation of the electrostatic recording apparatus is stopped and the aggregated magnetic toner is conveyed to the recording section W when the operation of the electrostatic recording apparatus is restarted.

Next, some other embodiments of the present invention are shown in FIG.
This will be explained based on FIGS. 1 to 13. It should be noted that the same constituent members as in the above embodiment are given the same reference numerals and the explanation thereof will be omitted.

In the embodiment shown in FIG. 11, a coil conveying member 19 that generates a traveling wave magnetic field by an excitation coil instead of a magnet roll is used as the developer conveying means, and the developer conveying path is formed into a non-circular path. It is something. The coil conveyance member 19 includes a base body 20 formed of a magnetic material with a non-circular cross section.
A large number of grooves 20a extending parallel to the width direction are formed in the outer peripheral surface of the excitation coil 2, and a conductive wire is wound between each groove 20a.
1. When this excitation coil 21 is divided into n groups and an alternating current with a phase shift of π/n is applied to each group, a traveling wave magnetic field is generated that travels in the direction of arrow T along the outer peripheral surface of the coil conveying member 19. . A recording electrode sheet 17 having the same structure as in the above embodiment is laid on the outer peripheral surface of this coil conveying member 19, one end of which is drawn into the base body 20, and a recording electrode drive circuit element 18 is mounted thereon. Since the developer conveyance means using the coil conveyance member 19 of this example does not use a rotating member, the durability of the device is improved, and the developer conveyance path can be freely set, which greatly promotes miniaturization of the device. becomes possible.

In the embodiment shown in FIG. 12, a pair of magnet rolls 22, 22 are used as the developer conveying means, and the developer is moved along the surface of the oval developer carrying member 23 by the cooperative action of their rotating magnetic fields. The material is conveyed in the direction of the arrow H. In this case as well, the recording electrode sheet 17 constructed in the same manner
One end, which will become a recording electrode, is laid along the surface of the developer carrying member 23, and the other end is drawn into the inside of the developer carrying member 23, and a recording electrode drive circuit element 18 is mounted thereon.

Furthermore, in the embodiment shown in FIG. 13, a magnet roll 25 is disposed inside the developing sleeve 24, one end of the recording electrode sheet 26 is laid on the circumferential surface of the developing sleeve 24, and the other end is placed on the developing sleeve 24. The recording electrode drive circuit element 18 is mounted on the end of the recording electrode. In this case, a plurality of openings 26a are formed along the width direction of the recording electrode sheet 26 so as not to block the progress of the developer.

In any of the three embodiments described above, the disturbance electrode EA is provided upstream of the recording electrode EL, similarly to the embodiment shown in FIG. As a result, as in the embodiment shown in FIG. 5, aggregation of the developer is prevented, and a high-quality recorded image with high resolution and no image defects can be stably formed. In the embodiment shown in FIG. 10, the disturbance electrodes EA are not arranged in parallel over the entire width direction, but are arranged locally at symmetrical positions with respect to the center in the width direction. can be solved efficiently.

It should be noted that the present invention is not limited to the specific embodiments described above, and it goes without saying that various modifications can be made within the technical scope of the present invention.

For example, in the embodiment shown in FIG. 2, a negatively (-) chargeable toner is used, but it is also possible to use a positively (+) chargeable toner. In that case, the bias voltage applied to the recording electrode and the counter electrode may be of positive (+) polarity.

Further, as the developer, a two-component developer in which a magnetic carrier and an insulating toner are mixed in a predetermined ratio can also be used. In this case, although the toner and carrier have different frictional charging polarities, they form a pair of toner and carrier when they are triboelectrically charged during the transport process to the recording section, and the pair as a whole is charged to the same polarity as the toner. Therefore, similarly to the above-described embodiments, the pair of toner and carrier can also be moved in the width direction of the developer transport path by the stirring electrode, and toner aggregation can be reliably prevented.

[0047]

As described in detail above, according to the present invention, a plurality of recording electrodes are laid in parallel on the surface of a developer carrying member, which serves as a developer transport path, with a minute gap maintained between them and the opposing electrodes. By disposing a plurality of disturbance electrodes on the upstream side of the recording electrode with respect to the developer transport direction, and applying a voltage to these disturbance electrodes so as to form an electric field that moves in a direction different from the developer transport direction, By moving the developer in a direction different from the predetermined conveyance direction, aggregation can be efficiently prevented, and the developer that is uniformly distributed can be stably conveyed to the electrode facing portion where a recorded image is formed. Therefore, image defects and image density variations caused by developer aggregation are prevented, and
Adhesion of the developer to the recording electrode is reliably prevented, making it possible to stably form a high-resolution, high-quality recorded image. Furthermore, since it is a non-contact recording method, there is no risk of the recording electrodes being worn out. Therefore, the durability of the recording head is improved, and the above-mentioned high-resolution, high-quality recorded images can be stably formed over a long period of time.

[Brief explanation of the drawing]

FIG. 1 is a schematic cross-sectional view showing the overall configuration of an electrostatic recording device as an embodiment of the present invention.

FIG. 2 is a schematic cross-sectional view showing a recorded image forming unit and its peripheral configuration in the electrostatic recording apparatus.

FIG. 3 is a plan cross-sectional view showing a horizontal circulation path of the recording image forming unit.

FIG. 4 is a perspective view showing the entire recording image forming unit.

FIG. 5 is a schematic cross-sectional view showing the configuration of the recording section and its surroundings of the recording image forming unit.

FIG. 6 is a plan view showing the recording section.

FIG. 7 is a schematic cross-sectional view showing the recording section.

FIG. 8 is a plan view showing another embodiment of the recording section.

FIG. 9 is a plan view showing still another embodiment of the recording section.

10 is a sectional view taken along the line XX in FIG. 5 showing the detailed configuration of the recording section.

FIG. 11 is a perspective view showing another embodiment of the present invention.

FIG. 12 is a perspective view showing still another embodiment of the present invention.

FIG. 13 is a perspective view showing still another embodiment of the present invention.

[Explanation of symbols]

4...Transfer charger 5...Cylindrical electrode 5a...Bias power supply (cylindrical electrode side) 11...Developer storage tank 12...Development recording tank 13...Horizontal circulation route 14a, 14b... Augerol 15, 24...Developing sleeve 16, 22, 25... Magnet roll 17, 26...Recording electrode sheet 17a...Recording electrode line 17c...Insulation coat 18...Drive circuit element 19...Coil conveyance member 21... Excitation coil EA...disturbing electrode EL...Recording electrode G...step Q...AC power supply S...Central space U...recording image forming unit W...recording section

Claims (3)

[Claims] 1. A developer transport means for transporting the developer along a predetermined developer transport path, and a plurality of developer transport means arranged in parallel at intervals in the width direction perpendicular to the developer transport direction on the developer transport path. The developer has a recording electrode and a counter electrode arranged with a required gap from the recording electrode, and a voltage is applied to each of the recording electrodes according to recording information, and the developer is conveyed along the developer conveyance path. In an electrostatic recording device that selectively transfers a developing agent to the opposite electrode side, a plurality of developer stirring electrodes are provided near the upstream side of the recording electrode with respect to the developer conveying direction, in a direction different from the developer conveying direction. An electrostatic recording device characterized in that the developer is disturbed by applying a voltage to each of the developer-disturbing electrodes so as to form an electric field that moves along the direction in which the electrodes are arranged. 2. The disturbance electrodes are arranged substantially symmetrically from the width center of the developer transport path to both sides, and a voltage is applied to each of the disturbance electrodes so that the electric field moves symmetrically with respect to the width center. The electrostatic recording device according to claim 1. 3. The electrostatic recording device according to claim 1, wherein a voltage is continued to be applied to the disturbance electrode even after the developer has been transported by the developer transport means.