JPH1086432A - Image-forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a low-cost image-forming apparatus which can form images of high resolution with a small number of driving elements and obtain good images with a small control voltage. SOLUTION: An aperture electrode body 1 is formed of rows of apertures 6a and 6b arranged zigzag and selection electrodes 5a and 5b set correspondingly to the apertures 6a and 6b. A control electrode 4 is forked to electrodes 4a and 4b correspondingly to the apertures 6a and 6b. Moreover, rows of the selection electrodes 5a and 5b are connected to output terminals A and B of a selection electrode-driving device 9. A voltage of 0V or +30V is applied with a predetermined cycle alternately to the selection electrodes 5a and 5b by the driving device 9, thereby selecting the supply of toners to the apertures 6a and 6b. The toner is controlled to pass only through one of the apertures 6a and 6b by an application voltage of the control electrode 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus applied to a copying machine, a printer, a facsimile, a plotter, and the like.

[0002]

2. Description of the Related Art Conventionally, a plurality of apertures (hereinafter, referred to as apertures) as passage portions are formed in an insulating sheet, and a control electrode made of a metal thin film is formed corresponding to each of the apertures. An image forming apparatus using an aperture electrode body as charged body flow control means, wherein an electric signal is applied to the control electrode based on image data, so that charged toner particles as a charged body are provided. An image forming apparatus for controlling the passage of an aperture to obtain an image on a recording medium is disclosed in, for example, Japanese Patent Application Laid-Open No. 6-155798.

[0003] The conventional image forming apparatus having the above-described structure includes the aperture electrode body and a toner bearing member which is a cylindrical roller member for carrying the charged toner on the surface thereof and supplying the toner to the aperture. A roller, and one surface of the aperture electrode body and the peripheral surface of the toner carrying roller are configured to be in contact with each other via the toner in a portion near the aperture row. By applying a voltage based on image data, the charged toner is controlled to pass through the aperture, and the toner flies onto a recording medium (not shown) disposed on the opposite side of the toner carrying roller across the aperture electrode body. Then, a toner image is formed on the recording medium.

According to this image forming apparatus, since the toner on the toner carrying roller and the aperture electrode body are in contact with each other in the vicinity of the aperture via the toner, the toner which adheres to the vicinity of the aperture to close the aperture is used. Is scraped off with the toner conveyed later, so that the aperture is not clogged.

[0005] Further, the toner carried on the toner carrying roller and supplied to the aperture is applied to the toner carrying roller by a physical force such as van der Waals force in addition to the mirror image force due to the charged charge of the toner. Since the toner is adhered, a large electric field, that is, a large control electrode applied voltage (hereinafter, referred to as a control voltage) is required to separate the toner from the toner-carrying roller surface only by the electric field generated by the control electrode.

However, in this image forming apparatus,
The toner carried on the toner carrying roller slides on the aperture electrode body near the aperture, receives a mechanical force, and is released from the adhesive force with the toner carrying roller. Can be controlled through the aperture. In addition, by arranging the aperture electrode body and the toner on the toner carrying roller so as to be in contact with each other, the control electrode on the aperture electrode body and the toner carrying roller are extremely close to each other, and a small control voltage is applied. , A strong electric field can be obtained, and a high contrast can be obtained with a smaller control voltage.

[0007]

However, in the conventional image forming apparatus as described above, in order to achieve high resolution output, the number of apertures and associated control electrodes becomes very large. For example, an aperture electrode body of A4 width size having a resolution of 400 dpi has about 330
There are as many as zero apertures and their corresponding control electrodes. In order to independently drive all of these control electrodes, the same number of output terminals of driving elements such as ICs are required, and naturally the required number of driving elements also increases. In particular, a driving element having a high withstand voltage is expensive, and using a large number of driving elements for higher resolution has a problem that the cost of the apparatus is greatly increased.

To solve such a problem, the present applicant disclosed in Japanese Patent Application Laid-Open No. Hei 4-153048 a reference electrode serving as a scanning electrode on one surface of an aperture electrode body and a data electrode serving as a data electrode on the other surface. An image recording apparatus has been proposed in which the number of drive elements is reduced by forming control electrodes and performing time-division driving using both of them.
An attempt was also made to apply it to the image forming apparatus described in JP-A-6-155798. However, according to this method, the toner is attracted to and adheres to the reference electrode or the toner repels according to the voltage applied to the reference electrode disposed on the surface contacting the toner carrying roller. Because the toner did not adhere to the reference electrode, the voltage applied to one reference electrode changed the amount of toner supplied to an aperture downstream of the reference electrode in the toner supply direction. (Same as the recording medium conveyance direction), and uneven recording density was generated, and it was difficult to obtain a good printed image.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and it is possible to form a high-resolution image with a small number of driving elements and obtain a good image with a small control voltage. It is an object to provide a low-cost image forming apparatus.

[0010]

In order to achieve this object, in an image forming apparatus according to the first aspect of the present invention, a plurality of passing portions and a plurality of passing portions are provided on one surface of an insulating substrate. And a charged material flow control means including a plurality of control electrodes provided one for each of two or more passing portions, and a charged material supply means for supplying a charged material to the charged material flow control means In the image forming apparatus, the charged material flow control means is provided on any surface of the insulating substrate, and the passing means is provided in the charged material supply direction by the charged material supply means. On the upstream side of the portion, a plurality of selection electrodes provided in the same number as the passage portions, and the selection electrodes at positions corresponding to the passage portions arranged at the same position in each of the control electrodes are electrically connected to each other. Connect to form multiple sets of select electrodes, all belonging to one set A plurality of connection lines for enabling the same voltage to be applied to the selection electrode, and via each of the connection lines, for each set of the selection electrodes, the charge body for attracting the charge body to the selection electrode; And a voltage having a polarity opposite to the polarity, and a selection voltage applying means for applying a voltage or a ground voltage having the same polarity as that of the charged body at a predetermined cycle to release the attracted charged body from the selection electrode. It is characterized by having.

That is, the supply of the charged body by the charged body supply means is on any surface of the insulating substrate constituting the charged body flow control means and is higher than the passing portion formed in the charged body flow control means. At a position on the upstream side in the direction, a plurality of selection electrodes provided in the same number as the passage portions are provided.

In addition, a plurality of the passing portions are provided for one control electrode, and one set of selection electrodes corresponding to one set of the passing portions having the same positional relationship with respect to the control electrode, A plurality of sets of selection electrodes are formed by being electrically connected to each other by connection lines. Therefore, the same voltage is applied to all the selection electrodes belonging to a certain set via the connection lines.

In forming an image, a voltage having a polarity opposite to that of the charged body for attracting the charged body to the selected electrode is applied to each set of the selected electrodes by a selection voltage applying unit. A voltage having the same polarity as that of the charged body or a ground voltage for releasing the attracted charged body from the selection electrode is applied at a predetermined cycle.

Therefore, a voltage or a ground voltage having the same polarity as that of the charged body is applied to one set of selection electrodes, and a voltage having a polarity opposite to that of the charged body is applied to another set of selection electrodes. By being applied, the charged body is supplied only to the passing portion corresponding to the one set of selection electrodes, and by applying the control voltage to the control electrode, recording can be performed only in the passing portion. With respect to the passages corresponding to the other sets of selection electrodes, the charged body is captured by the selection electrodes located upstream of the selected set of electrodes, and the passage of the subsequently supplied charged body is captured by the captured charge. Supply to the passage portion is not sufficiently supplied to the passage portion, and recording is not performed in the passage portion.

As described above, in the image forming apparatus according to the first aspect of the present invention, one set is selected from the plurality of sets of selection electrodes, and the supply of the charged material to the passing portion downstream thereof is selected.
By the selection, the charged body is supplied to the passing section, and in the passing section where the recording is enabled, the recording is performed by applying the data signal to the control electrode, and the recording is performed by scanning the set of selected electrodes. In this method, a set of effective passage portions is scanned, and the passage of charged bodies through all the passage portions is controlled in a time-division manner.

The image forming apparatus according to a second aspect of the present invention provides
It is characterized in that the selection electrode and the control electrode are formed on the same surface of the insulating substrate.

Further, the image forming apparatus according to claim 3 is
The selection electrode and the control electrode are formed on different surfaces of the insulating substrate, respectively.

Further, the image forming apparatus according to claim 4 is
A sliding surface having a larger coefficient of friction than the other region and the other surface is provided on one surface of the charged material flow control unit facing the charged body supply unit and in a region near the selection electrode. It is characterized by having been.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic configuration diagram of an image forming apparatus according to the present embodiment.

In FIG. 1, at the lower part of the image forming apparatus,
A toner supply device 10 as a charged material supply means is disposed, and an aperture electrode as a charged material flow control means for controlling passage of the toner 16 as a charged material is provided above the toner supply device 10. The body 1 is located.

Above the aperture electrode body 1, a back electrode roller 22 is rotatably arranged with an interval of about 1 mm. As shown in FIG. 1, the back electrode roller 22 is disposed such that the lowermost end thereof is directly above the aperture 6.

In the gap between the aperture electrode body 1 and the back electrode roller 22, a recording medium 20 is placed.
2 by the rotation in the direction of arrow D shown in FIG. 1 and the rotation of the transport roller 19, the paper is transported in the direction of arrow C shown in FIG. And a heat fixing device 26 including a heating roller.
The heat fixing device 26 can be replaced with any one of a heat fixing method and a pressure fixing method. Here, the rotation direction of the transport roller 19 is not shown, but is the same as that of the heat fixing device 26.

Next, each of the above components will be described in detail.

As shown in FIG. 1, the toner supply device 10 includes a toner case 11 which also serves as a housing of the toner supply device 10.

A toner 16, which is preferably a non-magnetic one-component insulating toner, is housed in the toner case 11, and a cylinder for carrying the toner 16 on the surface and transporting the toner 16 toward the aperture electrode body 1. A toner carrying roller 14, which is a shaped member, is disposed rotatably in the direction of arrow B shown in FIG.

As the toner carrying roller 14, a roller formed by forming a layer of a material such as a metal, a synthetic resin, or rubber around a central shaft made of metal can be used. It is preferable to be electrically conductive and grounded via the center rod, but in order to assist charging of the toner 16 or to improve recording characteristics,
It may be connected to an appropriate power supply or the like.

A supply roller 12 which is a cylindrical member for supplying the toner 16 contained in the toner case 11 to the toner carrying roller 14 is provided obliquely below the toner carrying roller 14 in FIG. , Are rotatably arranged in the direction of arrow A shown in FIG.

As the supply roller 12, a roller formed by forming a layer of sponge, rubber, or the like around a metal central shaft rod can be used. May be connected to a suitable power supply or the like to assist in the charging of the recording medium or to improve the recording characteristics.

The supply roller 12 and the toner carrying roller 14 are disposed so that their central axes are parallel to each other, and are disposed so as to be in pressure contact with each other via the toner 16 during a recording operation. Have been.

The toner 16 is charged to a predetermined polarity by rolling and friction between the supply roller 12 and the toner carrying roller 14 rotating in the same direction. In the present embodiment, the toner 16 is charged to a negative polarity.

In the toner case 11, above the supply roller 12, the toner 16 carried on the toner carrier roller 14 by frictional charging between the supply roller 12 and the toner carrier roller 14 is charged. The toner layer regulating blade 18, which is a plate-like member for adjusting the amount of toner 16 to be uniform on the roller surface of the toner carrying roller 14 and adjusting the amount of charge of the toner 16 as necessary, is provided at one end thereof. Are arranged so as to be pressed against the toner carrying roller 14.

When the charge amount of the toner 16 is to be adjusted as the material of the toner layer regulating blade 18, a conductive or semiconductive material is used and grounded or connected to an appropriate power supply device. In other cases, any material can be used regardless of conductivity or insulation.

FIG. 2 is a schematic diagram for explaining the structure of the aperture electrode body 1 used in the present image forming apparatus.

The aperture electrode body 1 as a charged body flow control means has an insulating sheet 2 as an insulating substrate and a diameter 6 mm.
Apertures 6 as passing portions having a circular cross section of about 0 μm are arranged in two rows in a staggered manner in the longitudinal direction of the aperture electrode body 1, and on one surface of the insulating sheet 2, The control electrode 4 which is a conductive pattern including a donut-shaped pattern portion surrounding the edge of the aperture 6 and a linear pattern portion for connecting the donut-shaped pattern portion to the output terminal of the control electrode driving device 8; The selection electrodes 5 which are conductive patterns provided in a row corresponding to the apertures 6 are formed above the apertures 6 in the above.

The insulating sheet 2 has a thickness of 25 μm.
For example, a synthetic resin film having a thickness of about m, for example, a polyimide film, a ceramic thin plate having a similar thickness, or the like can be used.

As a material of the control electrode 4 and the selection electrode 5, for example, a copper thin film having a thickness of about 8 μm or a metal thin film having good conductivity such as gold can be used. These are formed on the insulating sheet 2 by etching, vapor deposition,
It is formed by a method such as screen printing.

One end of the control electrode 4 is connected to an output terminal of a driving element provided in the control electrode driving device 8, and the other end is divided into two forks of control electrodes 4a and 4b. And 6b are correspondingly formed.

That is, the staggered aperture 6
In the set of apertures 6a, which are the upper row in FIG.
A set of select electrodes 5a corresponds, and a set of apertures 6b, which is one row below, is provided with a set of select electrodes 5b.

Further, the set of selection electrodes 5a is connected to connection lines 7a.
And is connected to the output terminal A of the selection electrode driving device 9. Similarly, the set of selection electrodes 5b is
The output terminal B of the selection electrode driving device 9 is connected via the connection line 7b.
It is connected to the.

The control electrode driving device 8 and the selection electrode driving device 9 apply 0 V or 0 V to the control electrode 4 and the selection electrodes 5 a and 5 b based on an image signal sent from image signal receiving means (not shown). It is configured to apply a voltage of + 30V. The image signal is transmitted from an external computer, image reading device, image communication device, or the like via an image signal receiving unit (not shown).

In FIG. 1, the aperture electrode body 1 is attached to the toner case 11 while applying tension.
The portion where the aperture 6 and the selection electrode 5 are formed is disposed so as to wind around the toner carrying roller 14, and at that portion, is pressed against the toner carrying roller 14 via the toner 16. The pressure contact surface at this time is the control electrode 4
And the surface on the back side of the surface on which the selection electrode 5 is formed.
Further, the selection electrode 5 is disposed upstream of the aperture 6 with respect to the direction of arrow B which is the toner supply direction.
The aperture electrode body 1 is installed on the toner case 11.

A DC power supply 24 is connected to the back electrode roller 22.
Is connected. The DC power supply 24 supplies the toner 16 passing through the aperture 6 to the back electrode roller 22.
, For example, +1 kV is applied during the recording operation.

Next, the recording operation of the image forming apparatus configured as described above will be described.

When the supply roller 12 rotates in the direction of arrow A shown in FIG. 1, the toner 16 contained in the toner case 11 is transported toward the toner carrying roller 14 which rotates in the direction of arrow B. You. Then, the toner 16
The toner supply roller 12 and the toner carrying roller 14, which rotate while being pressed against each other, are triboelectrically charged to a negative polarity, carried on the toner carrying roller 14, and moved in the longitudinal direction of the toner carrying roller 14 by the toner layer regulating blade 18. The amount of the toner 16 is made uniform, and the toner 16 is carried on the toner carrying roller 14 as a thin and uniform carrying layer.

The toner 16 thinned on the toner carrying roller 14 is conveyed toward the aperture electrode body 1 and comes into contact with the aperture electrode body 1 immediately below the selection electrode 5 with the insulating sheet 2 interposed therebetween. I do.

Here, recording control using the selection electrode 5 and the control electrode 4 will be described with reference to FIGS.

The selection electrode 5 uses one of the apertures 6a and 6b formed on the same control electrode 4 as a toner 16
Is selected as an effective passage part for controlling the passage of the vehicle.
The other that is not selected is an invalid passage section, that is, a passage section in which passage control of the toner 16 is not performed.

Specifically, as shown in FIG. 3, the selection electrode 5 to which +30 V was applied in the aperture electrode body 1 was used.
The toner 16 charged to the negative polarity is attracted by the electrostatic force on the back surface of the a, and the toner 16 supplied later is blocked by the attracted toner 16, and the supply of the toner 16 to the aperture 6 a is stopped. By being inhibited, this aperture 6a becomes invalid. That is, regardless of the control voltage applied to the control electrode 4a, the toner 16 does not pass through the aperture 6a.

On the other hand, as shown in FIG. 4, the toner 16 is not attracted to the back surface of the selection electrode 5b to which 0 V is applied, and the toner 16 is supplied to the aperture 6b without any hindrance. . Therefore, the passage of the aperture 6b can be controlled by the voltage applied to the control electrode 4b.
That is, the aperture 6b is an effective passage section.

Here, the toner 16 rolls on the surface of the toner carrying roller 14 by sliding due to the contact with the toner carrying roller 14 when the toner 16 is conveyed toward the aperture 6b which is an effective passage portion, Since the toner is supplied below the aperture 6b in a state where the adhesive force with the toner carrying roller 14 is reduced, whether or not the toner passes through the aperture 6b is controlled with a small control voltage.

A voltage is applied to each control electrode 4b corresponding to the effective aperture 6b according to an image signal.
More specifically, the control electrode driving device 8 supplies +30 V to the position corresponding to the position where the dot is to be formed by the toner 16.
, And a voltage of 0 V is applied from the control electrode driving device 8 to those corresponding to the non-dot forming positions.

Here, in the vicinity of the aperture 6b corresponding to the control electrode 4b to which the voltage of +30 V is applied, the potential difference between the control electrode 4b and the toner carrying roller 14 causes the control electrode 4b to transfer the toner to the toner carrying roller 14. A heading electric field line is formed. Due to the lines of electric force, the negatively charged toner 16 supplied below the aperture 6b receives an electrostatic force in the direction of higher potential, passes through the aperture 6b from above the toner carrying roller 14, and is drawn out to the control electrode 4b side. It is.

Further, no electric field is formed between the toner carrying roller 14 and the control electrode 4 near the aperture 6b corresponding to the control electrode 4b to which 0 V is applied, and the toner 16 is charged by the control electrode 4b. Aperture 6 without power
b.

At this time, the same voltage is applied to the adjacent control electrode 4a connected to the control electrode 4b.
As shown in (2), since the supply of the toner 16 to the aperture 6a is blocked by the attached toner 16 below the selection electrode 5a, the toner 16 is not supplied directly below the control electrode 4a and the aperture 6a. Therefore, regardless of the control voltage applied to the control electrode 4a, the toner 16 is not drawn out from the aperture 6a, which is an invalid passage.

The toner 16 extracted from the control electrode 4b
Is further applied to the back electrode roller 22.
the recording medium 20 and the aperture electrode body 1
And flies toward the recording medium 20 and is deposited on the recording medium 20 to form dot-shaped pixels.

When recording for one line of the aperture 6b is completed, subsequently, +30 V is applied to the selection electrode 5b, and the selection electrode 5a
By applying 0 V to the control electrode 4a and the aperture 6a, the control electrode 4a and the aperture 6b are selected as valid, and the control electrode 4b and the aperture 6b are invalidated. And controls the passage of the toner 16 through the aperture 6a.

The recording medium 20 conveyed through the gap between the aperture electrode body 1 and the back electrode roller 22 is moved while the dot-shaped pixels of the toner 16 are formed on the surface thereof.
It is sent in a direction orthogonal to the row of apertures 6. Then, by repeating the above-described process, an image using the toner 16 is formed on the entire surface of the recording medium 20. Thereafter, the image formed by the toner 16 formed on the recording medium 20 is fixed on the recording medium 20 by the heat fixing device 26.

Here, assuming that the conveying speed of the recording medium 20 is α (unit: mm / s), and the distance between the row of the apertures 6a and the row of the apertures 6b is d (unit: mm), d / α (unit:
When the aperture 6a and the aperture 6b are switched between valid and invalid in the cycle of s), the dot-shaped pixels formed by both are arranged in a line.

As described above, in the image forming apparatus of the present embodiment, a plurality of apertures 6 are formed for one control electrode 4, and one of them is selected by using the selection electrode 5. And only the selected valid aperture 6 is
The toner 16 is caused to pass by the voltage applied to the control electrode 4. The scanning of the selection electrode 5 controls the passage of the toner 16 in all the apertures 6 in a time-division manner.

At this time, the validity / invalidity of the aperture 6 is selected by supplying the toner 16 directly below the aperture 6 or the toner adhered to the back surface of the selection electrode 5 of the aperture electrode body 1 by electrostatic attraction. Whether the supply of the toner 16 to the area immediately below the aperture 6 is prevented by the control of the selection electrode 5 is determined by controlling the voltage applied to the selection electrode 5. Therefore, the selection of the validity / invalidity of the aperture 6 is easily and reliably performed.

Further, the number of output terminals of the control electrode driving device 8 to be connected to the control electrode 4 can be reduced to half in the above-described embodiment as compared with the conventional image forming apparatus. This is because two apertures 6 can be controlled using one control electrode 4. If three or more apertures 6 are formed on one control electrode 4, the required number of output terminals is further reduced,
The number of driving elements such as ICs required for the control electrode driving device 8 can be reduced, and a low-cost image forming apparatus can be provided.

The present invention is not limited to the embodiment described in detail above, and various changes can be made without departing from the gist of the present invention.

For example, in the above embodiment, the selection electrode 5 and the control electrode 4 are formed on the same surface of the insulating sheet 2. In this case, a manufacturing process such as an etching process when forming the selection electrode 5 and the control electrode 4 can be simplified. That is, the selection electrode 5 and the control electrode 4 are
By forming them on the same surface of the insulating sheet 2, exposure of a resist pattern or the like can be performed at once, and there is no need to separate the steps for forming the selection electrode 5 and the control electrode 4.

On the other hand, the selection electrode 5 and the control electrode 4 are formed on different surfaces of the insulating sheet 2, and the image formation is performed such that the selection electrode 5 side faces the toner carrying roller 14 in FIG. The device may be configured. In this case, since the distance between the toner carrying roller 14 and the selection electrode 5 becomes short, the electric field for selecting the validity / invalidity of the aperture 6 becomes strong, the selectivity is improved, and the voltage is applied to the selection electrode 5. Can be reduced, and an inexpensive driving element such as an IC can be used as the control electrode driving device 8, so that the production cost of the image forming apparatus can be reduced.

In the above embodiment, the friction coefficient of the surface on which the toner 16 is attracted by the selection electrode 5 is not described, but the friction coefficient is large, for example, the surface roughness is made larger than other portions. It is preferable to provide a surface. As a result, the effect of preventing the toner 16 from being damped by the selection electrode 5 during non-selection is improved.

Further, in the above-described embodiment, the aperture electrode body 1 having the circular apertures 6 arranged in a row is used as the charged body flow control means, but, for example, a polygonal shape such as a triangle or a quadrangle is used. The shape may be used.
It is also possible to use a mesh-shaped electrode body as described in JP-A-03221.

[0068]

As is clear from the above description,
In the image forming apparatus according to the first aspect of the present invention, one set is selected from a plurality of sets of selection electrodes, and a charged material is supplied only to a passing portion located downstream thereof, so that an effective passage for recording is provided. Select the section, and control the passage of the charged body by applying a signal to the control electrode in the effective passage section, and scan the effective passage section by scanning the voltage application of the selection electrode to time division. In addition, it is possible to control the passage of the charged body through all the passage portions. Therefore, since a large number of apertures can be controlled with a small number of drive elements, an image forming apparatus capable of forming a high-resolution image with a small control voltage can be provided at low cost.

The image forming apparatus according to claim 2 is
Since the selection electrode and the control electrode are formed on the same surface of the insulating substrate, there is no need to separate the steps for forming the selection electrode and the control electrode, and the manufacturing process can be simplified.

The image forming apparatus according to claim 3 is
Since the selection electrode and the control electrode are respectively formed on different surfaces of the insulating substrate, the voltage applied to the selection electrode can be reduced, and an inexpensive driving element such as an IC can be used. Therefore, there is an effect that the manufacturing cost of the image forming apparatus can be reduced.

The image forming apparatus according to claim 4 is
A sliding surface having a larger coefficient of friction than the other region and the other surface is provided on one surface of the charged material flow control unit facing the charged body supply unit and in a region near the selection electrode. As a result, the effect of selecting the supply of the charged body to the passing portion is improved, and thus the effect of selecting whether the passing portion is valid or invalid is improved.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram illustrating an image forming apparatus according to an embodiment of the present invention.

FIG. 2 is a diagram illustrating a configuration of an aperture electrode body mounted on the image forming apparatus.

FIG. 3 is a cross-sectional view for explaining an operation in which an aperture 6a is invalidated.

FIG. 4 is a cross-sectional view for explaining an operation in which an aperture 6a is effective.

[Explanation of symbols]

 Reference Signs List 1 aperture electrode body 4, 4a, 4b control electrode 5, 5a, 5b selection electrode 6, 6a, 6b aperture 7a, 7b connection line 8 control electrode driving device 9 selection electrode driving device 14 toner carrying roller 16 toner

Claims (4)

[Claims] 1. A plurality of passing portions provided on an insulating substrate for allowing a charged body to pass therethrough, and a plurality of passing portions provided on one surface of the insulating substrate and corresponding to two or more passing portions. An image forming apparatus comprising: a charged body flow control unit including a plurality of control electrodes provided one by one; and a charged body supply unit configured to supply a charged body to the charged body flow control unit. Charged body flow control means is provided on any surface of the insulating substrate, in the supply direction of the charged body by the charged body supply means, upstream of the passage section, the same number as the passage sections. A plurality of selected electrodes, and a set of a plurality of selected electrodes by electrically connecting the selected electrodes at positions corresponding to the passage portions arranged at the same position in each of the control electrodes, The same voltage can be applied to all selected electrodes belonging to one set A plurality of connection lines for connecting, via each of the connection lines, a voltage having a polarity opposite to that of the charged body for attracting the charged body to the selected electrode, for each set of the selected electrodes; And a selection voltage applying means for applying a voltage of the same polarity as the charged body or a ground voltage at a predetermined cycle for releasing the charged body from the selection electrode. Forming equipment. 2. The image forming apparatus according to claim 1, wherein the selection electrode and the control electrode are formed on the same surface of the insulating substrate. 3. The image forming apparatus according to claim 1, wherein the selection electrode and the control electrode are respectively formed on different surfaces of the insulating substrate. 4. The charged-body flow control means is provided on one surface of the charged-body flow control means facing the charged body supply means, and in another area in the vicinity of the selection electrode. 4. The image forming apparatus according to claim 1, further comprising a sliding surface having a larger coefficient of friction than the other surface.