JPH1120221A - Image forming toner supply device and image forming device - Google Patents

Abstract

(57) Abstract: An image forming toner supply device and the like capable of uniforming a toner layer to form a clear image even when a toner layer is uneven due to contact between an electrode array and a toner carrying roller. SOLUTION: An electrode array 1 is separated from a toner carrying roller 14 on which a toner 16 is carried by forming a toner layer, and a toner carrying roller 14 and a supply roller 12 are provided.
By rotating the agitator 17 at high speed, the toner layer on the surface of the toner carrying roller 14 is made uniform, and new toner 16 is adapted to the toner carrying roller 14 and the supply roller 12. At this time, regarding the separation of the electrode array 1, the arm 7 a is rotated clockwise and the arm 7 b is rotated counterclockwise to deflect the electrode array 1 whose both ends in the short direction are fixed to the toner case 11. Separation by convergence. As another separation method, the electrode array 1 is fixed to a holder formed so as to surround the periphery of the toner case 11, and the holder is moved to separate the electrode array 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method in which an electric field is applied to a thinned and supported charged toner, thereby causing the toner to fly and causing the toner to adhere directly to recording paper. It belongs to the technical field of an image forming apparatus for forming an image.

[0002]

2. Description of the Related Art Conventionally, as one type of this type of image forming apparatus, an electrode having a large number of small openings (hereinafter, referred to as apertures) through which toner passes and having control electrodes around the apertures is provided. By providing an array and applying a drive voltage based on recording information to be recorded to the control electrode to generate an electric field, it is possible to selectively control in which aperture the toner flies and passes. There is an image forming apparatus that obtains an image by directly adhering the toner that has passed through the aperture onto the recording medium such as a recording sheet, and the details thereof are disclosed in, for example, JP-A-6-155798.

As such an image forming apparatus, for example, as shown in FIG. 6A, the apertures 106 are formed in a line in a direction perpendicular to the paper surface of FIG. Control electrode 10 at a position corresponding to
Toner carrying roller 114 carrying the thinned toner 116 with the electrode array 101 on which
And the recording paper 120 are opposed to each other.
There is an image forming apparatus 100 having a configuration in which a back electrode 122 to which a back voltage is applied from a back voltage application circuit 110 is provided on the back of the image forming apparatus 100. In the image forming apparatus 100, a control voltage corresponding to recording information to be recorded is applied to the control electrode 104 from the control voltage applying circuit 108, and the aperture 1 of the charged toner 116 carried by the toner carrying roller 114 is applied.
06 is controlled, and an image is formed on the recording paper 120.

On the other hand, with respect to the supply of the toner 116 to the toner carrying roller 114, the toner 116 stored in the housing is attached to the surface of the toner carrying roller 114 while being charged by the toner supplying roller 112, and the attached toner 116 is charged. The thickness of the toner 116 is controlled by a metal blade-shaped layer thickness control blade 118 to reduce the thickness.

At this time, since the electrode array 101 and the toner carrying roller 114 charge the toner 116,
The toner 116 is in contact with a predetermined area with the toner 116 interposed therebetween. This contact state will be described with reference to FIG. 6B. The electrode array 101 is arranged such that the vicinity of the central axis in the longitudinal direction (the direction perpendicular to the paper surface of FIG. 6) is in contact with the surface of the toner carrying roller 114. Have been. The center line of each aperture 106 in the longitudinal direction of the electrode array 101 and the center axis 115 of the toner carrying roller 114 are located on the same plane. Further, as shown in FIG. 6B, the electrode array 101 itself is
Are pressed against each other by the same angle to the left and right about the central axis in the longitudinal direction.

With the above configuration, the charged toner 1
16 can be attached to the recording paper 120 by flying inside the aperture 106 to form an image.

[0007]

However, if the image formation by the image forming apparatus 100 is continued for a long time, the toner
Has a problem that the thickness of the layer cannot be controlled even by the layer thickness control blade 118, whereby a clear image cannot be formed. That is, in the image forming apparatus 100, the layer thickness of the toner 116 on the toner carrying roller 114 is, for example, about several μm (specifically, the surface of the toner carrying roller 114 (Thickness of 0.2 to 0.3 mg / cm ² in terms of toner weight per unit area), but the back surface of the electrode array 101 has a toner 116 If image formation is continued by rotating the toner carrying roller 114 for a long time while keeping the pressure contact with the toner, the layer thickness of the toner 116 is reduced due to the pressure contact between the electrode array 101 and the toner carrying roller 114. Even if the layer thickness control blade 118 is used, unevenness that cannot be controlled occurs. This results in that the toner 116 passes through the aperture 106 and flies excessively in a portion where the layer thickness is large, and an image darker than a desired density is formed. Then
The flying amount of the toner 116 will be too small, and in this case, an image lighter than the desired density will be formed.

Here, the cause of the above-mentioned unevenness of the toner layer is caused by unevenness in the longitudinal direction of the electrode array 101 (that is, uneven contact pressure) at a contact portion between the electrode array 101 and the toner carrying roller 114. Can be
In this case, the electrode array 101 or the toner carrying roller 11
In the portion where any one of 4 is convex, the toner 116 is peeled off from the toner carrying roller 114 and stays in the peripheral portion of the convex. Then, the toner layer is disturbed by irregularities due to the stripping and the stagnation. The unevenness of the toner layer due to stripping and staying is particularly noticeable immediately after replenishment of new toner. This is because a new toner often has a non-uniform charge amount or poor fluidity, so that the adhesion to the toner carrying roller 114 becomes unstable, and the toner 116 is liable to peel or stay.

On the other hand, the reason why the above-mentioned unevenness of the toner layer cannot be controlled (cannot be reduced in thickness) even by the layer thickness control blade 118 is that the layer thickness control blade 118 is originally transported to a predetermined thickness (thin layer reduction). This is to apply a certain frictional force to the toner layer (thickness before the toner layer is removed) to peel off the excess thickness of the toner layer. Therefore, regarding the unevenness of the layer thickness that occurs before reaching the layer thickness control blade 118, if the toner layer is partially pressed and solidified or is excessively charged, the layer thickness control blade 118 setstle this. As a result, it is impossible to restore the toner layer to a uniform thickness.

Therefore, the present invention has been made in view of the above-mentioned problems, and has as its object to reduce the unevenness of the toner layer even if the toner layer is uneven due to the contact between the electrode array 101 and the toner carrying roller 114. The present invention is to provide an image forming toner supply device capable of forming a sharp and clear image and an image forming device provided with the image forming toner supply device.

[0011]

According to a first aspect of the present invention, there is provided an image forming apparatus, comprising: a plurality of apertures for passing charged toner; and a plurality of apertures corresponding to the respective apertures. A control electrode disposed at a position, a plurality of control electrodes for controlling the passage of the toner, an electrode array formed on a dielectric substrate, carrying the toner on the surface, the toner A toner carrier such as a toner carrier roller for supplying the toner to the opening by contacting the back surface of the surface of the dielectric substrate on which the control electrode is formed; and a supply for supplying the toner to the toner carrier. A toner supply member such as a roller, a layer thickness control blade for controlling a layer thickness of the toner carried on the toner carrier, and a control information for each of the control electrodes, based on recording information to be recorded on a recording medium. hand By independently applying a voltage, the toner passes from the toner carrier through the opening to selectively reach the recording medium, and forms an image corresponding to the recording information on the recording medium. An image forming toner supply device such as a toner supply unit including a control electrode driving unit such as a control voltage application unit, wherein the electrode array is separated from the toner carrier, and the toner is applied to the back surface of the electrode array. Separating means such as an arm for preventing the toner from contacting the toner carrier, and operating means such as a CPU for operating the toner carrier and the toner supply body in a state where the toner on the toner carrier is not in contact with the back surface. Prepare.

According to the operation of the first aspect of the present invention, the separating means separates the electrode array from the toner carrier so that the toner does not contact the back surface of the electrode array.

The operating means operates the toner carrier and the toner supplier in a state where the toner on the toner carrier is not in contact with the back surface of the electrode array.

Therefore, even if the toner layer on the toner carrier is uneven due to the contact of the electrode array,
After the contact between the electrode array and the toner is released, the unevenness can be removed by the toner supply member and the layer thickness control blade.

According to a second aspect of the present invention, there is provided an image forming toner supply apparatus according to the first aspect, wherein the separating means is provided with the electrode array every predetermined period. In addition to separating the toner carrier, the operating means is configured to operate the toner carrier and the toner supply when the electrode array is separated from the toner carrier.

According to the operation of the second aspect of the invention, in addition to the operation of the first aspect of the present invention, the separating means separates the electrode array from the toner carrier every predetermined period, and Since the operating means operates the toner carrier and the toner supply member when the electrode array and the toner carrier are separated from each other, the unevenness of the toner layer can be periodically removed.

According to a third aspect of the present invention, there is provided an image forming toner supply apparatus according to the first or second aspect, wherein the separation means is provided with respect to the image forming toner supply apparatus. When the power is turned on, the electrode array and the toner carrier are separated from each other, and the operating unit moves the toner carrier and the toner supply member when the electrode array is separated from the toner carrier. It is configured to operate.

According to the operation of the third aspect of the invention, in addition to the operation of the first or second aspect of the present invention, when the power supply is turned on to the image forming toner supply device, the electrode array is provided. And the toner carrier, and the operating means operates the toner carrier and the toner supply when the electrode array and the toner carrier are separated from each other.
It is possible to remove the unevenness that occurs immediately after the power is turned on.

According to a fourth aspect of the present invention, there is provided an image forming toner supply apparatus as set forth in any one of the first to third aspects, wherein the operating means comprises an electrode array When the toner carrier is separated from the toner carrier, the toner carrier and the toner supply body are operated at a higher speed than in a normal operation.

According to the operation of the invention described in claim 4, in addition to the operation of the invention described in any one of claims 1 to 3, in addition to the operation means, the operating means is provided so that the electrode array and the toner carrier are separated from each other. In this case, since the toner carrier and the toner supply body are operated at a higher speed than in the normal operation, the unevenness can be removed more quickly.

According to a fifth aspect of the present invention, there is provided an image forming toner supply device according to any one of the first to fourth aspects, wherein the toner is stored and the toner is stored. An agitator for supplying to a supply body, a storage unit such as a storage unit, and the separation unit separates the electrode array and the toner carrier when the storage unit is supplied with new toner. The operating means operates the toner carrier, the toner supply body, and the storage means when the electrode array and the toner carrier are separated from each other.

According to the operation of the invention described in claim 5, in addition to the operation of the invention described in any one of claims 1 to 4, the storage means stores the toner and supplies the toner to the toner supply body. Supply.

On the other hand, the separation means separates the electrode array from the toner carrier when new toner is supplied to the storage means.

The operating means operates the toner carrier, the toner supply body and the storage means when the electrode array and the toner carrier are separated from each other.

Therefore, the replenished new toner can be quickly applied to the toner carrier and the toner supplier.

According to a sixth aspect of the present invention, there is provided an image forming toner supply apparatus according to the fifth aspect, wherein the operating means is configured to separate the electrode array from the toner carrier. During the operation, the toner carrier, the toner supply body, and the storage unit are operated at a higher speed than in the normal operation.

According to the function of the invention described in claim 6, in addition to the function of the invention described in claim 5, when the operating means is separated from the electrode array and the toner carrier, the toner carrier and the toner carrier are separated. Since the toner supply unit and the storage unit are operated at a higher speed than in the normal operation, the supplied new toner can be more quickly applied to the toner carrier and the toner supply unit.

According to a seventh aspect of the present invention, there is provided an image forming toner supply apparatus according to any one of the first to sixth aspects, wherein the dielectric substrate is an elastic body. In addition, the separation means is configured to separate the electrode array and the toner carrier by bending the dielectric substrate.

According to the function of the invention described in claim 7, in addition to the function of the invention described in any one of claims 1 to 6, the dielectric substrate is an elastic body, and the separating means includes: The electrode array and the toner carrier are separated by bending the dielectric substrate.

Therefore, the structure of the separating means can be simplified.

In order to solve the above-mentioned problem, the invention according to claim 8 is directed to the image forming toner supply device according to any one of claims 1 to 6, wherein the separation means includes an electrode array. The supporting unit for supporting is moved in a direction in which the electrode array and the toner carrier are separated from each other, so that the electrode array and the toner carrier are separated from each other.

According to the operation of the invention described in claim 8, in addition to the operation of the invention described in any one of claims 1 to 6, the separating means includes a supporting portion for supporting the electrode array. The electrode array is moved away from the toner carrier by moving the electrode array away from the toner carrier.

Therefore, the electrode array and the toner carrier can be separated without applying a load to the electrode array.

According to a ninth aspect of the present invention, there is provided an image forming toner supply apparatus according to any one of the first to eighth aspects, wherein the electrode array is provided with the recording medium interposed therebetween. And a back electrode such as a back electrode plate that assists the toner to reach the recording medium by applying a voltage corresponding to the application of a voltage to each of the control electrodes; A fixing unit such as a fixing device that fixes the toner on the recording medium by heating and pressurizing the recording medium to which the toner has arrived and attached; and a conveyance unit that conveys the recording medium from the position of the electrode array to the fixing unit. And a transport unit such as a roller.

According to the function of the ninth aspect of the present invention, in addition to the function of the first aspect of the present invention, the recording medium is arranged to face the electrode array with the recording medium interposed therebetween. The back electrode assists the toner to reach the recording medium by applying a voltage corresponding to the application of a voltage to each control electrode.

On the other hand, the fixing section fixes the toner on the recording medium by heating and pressing the recording medium to which the toner has arrived and adhered.

At this time, the transport section transports the recording medium from the position of the electrode array to the fixing section.

Accordingly, it is possible to form an image corresponding to recorded information on a recording medium clearly by removing unevenness in the toner layer.

[0039]

Next, a preferred embodiment of the present invention will be described with reference to the drawings. Note that, in the embodiment described below, an electric field is applied to a charged toner that is thinned and carried, thereby causing the toner to fly and causing the toner to adhere directly to recording paper. 1 is an embodiment when the present invention is applied to an image forming apparatus that forms an image.

(I) First Embodiment First, a first embodiment of the present invention will be described with reference to FIGS. Here, FIG. 1 is a longitudinal sectional view of the image forming apparatus S of the first embodiment, and is a longitudinal sectional view showing a state at the time of image formation in which an electrode array and a toner carrying roller are in contact with each other, and FIG. FIG. 3 is a longitudinal sectional view of the image forming apparatus S. FIG. 3 is a vertical cross-sectional view of the image forming apparatus S. The non-image forming state in which the electrode array is separated from the toner carrying roller, and each roller and the agitator idles together with the toner is shown. FIG.

As shown in FIG. 1, the image forming apparatus S includes a toner supply device 10 as an image formation toner supply device,
A back electrode plate 22, a fixing device 26 as a fixing unit, a set of conveyance rollers 19 as a conveyance unit, a control voltage application circuit 8 as a control electrode driving unit, and a back voltage application circuit 24
And a CPU 13 as a separating means and an operating means.

On the other hand, the toner supply device 10 includes an aperture 6 and a control electrode 4 in a toner case 11 which is an external housing.
, A toner carrying roller 14 as a toner carrying body, a supply roller 12 as a toner supplying body, an agitator 17 arranged in a storing section 21 for storing toner, and a layer thickness control. It comprises a blade 18 and arms 7a and 7b as separating means.

Further, the fixing device 26 is of a thermal fixing type comprising a pressure roller 26a having a surface layer of silicon rubber or the like and a heat roller 26b having a halogen heater inside.

Next, a detailed configuration of the electrode array 1 will be described with reference to FIG.

As shown in FIG. 2A, in the electrode array 1 according to the embodiment, a plurality of rectangular apertures 6 are formed on a polyimide elastic insulating sheet 2 having a thickness of about 50 μm. The control electrodes 4 made of a copper thin film having a thickness of 5 μm are formed at a position between the apertures 6 at intervals of 80 μm in the direction. In addition,
The insulating sheet 2 may be formed using ceramics. Further, FIG. 2A shows the surface of the electrode array 1 on which the control electrodes 4 are formed, and the back surface of the surface shown in FIG. . Further, both ends in the short direction of the electrode array 1 are fixed to the toner case 11, and the vicinity of the inside of both ends in the short direction on the back surface is supported by arms 7a and 7b, respectively. The arms 7a and 7b are supported by shafts 7c and 7d, respectively, so as to be rotatable under the control of the CPU 13 in the directions shown in FIG. 1 (the arm 7a is clockwise and the arm 7b is counterclockwise). And the arm 7a
1 and 7b rotate while supporting the back surface of the electrode array 1 in the direction shown in FIG. 1 and both ends of the electrode array 1 in the short direction are fixed to the toner case 11, so that the electrode array 1 The central portion can be bent leftward in FIG. 1 to be separated from the toner carrying roller 14.

Next, the electrode array 1 and the toner carrying roller 1
The positional relationship of No. 4 will be described with reference to FIG.

As shown in FIG. 2B, the electrode array 1 at the time of image formation is arranged so that the vicinity of the longitudinal central axis of the insulating sheet 2 is in contact with the surface of the toner carrying roller 14. The center line in the longitudinal direction of the electrode array 1 of each aperture 6 and the center axis 32 of the toner carrying roller 14 are located on the same plane 30.

Further, as shown in FIG. 2 (b), the electrode array 1 itself is pressed against the toner carrying roller 14 so as to bend left and right by the same angle about the central axis in the longitudinal direction.

Thus, the contact area between the electrode array 1 and the toner carrying roller 14 with the toner 16 interposed therebetween can be increased.

Next, the operation of the image forming apparatus S according to the first embodiment will be described with reference to FIGS.

First, the operation when the electrode array 1 is pressed against the toner carrying roller, that is, the operation during image formation will be described.

The agitator 17 in the storage portion 21 of the toner 16 formed in the toner case 11 rotates in the direction C in FIG. It is fed little by little toward the roller 12. Then, the supply roller 12 rotatably mounted in the direction B in FIG. 1 conveys the toner 16 to the cylindrical toner carrying roller 14 disposed adjacent thereto by its rotation.

The surface of the supply roller 12 is formed of a foamed rubber such as urethane or silicon, and rotates while being in contact with the toner carrying roller 14. The toner 16 is negatively charged at the contact portion by the rotation accompanied with the contact, and is then carried on the surface of the toner carrying roller 14.

Next, the toner carrying roller 14 is rotatably mounted in the direction A in FIG.
6 is supplied to the aperture 6 of the electrode array 1. At this time,
At a position in the toner case 11 that comes into contact with the toner carrying roller 14, the layer of the toner 16 carried on the surface of the toner carrying roller 14 is controlled to be thin and uniform, and the carried toner 16 is A layer thickness control blade 18 for uniformly triboelectric charging is provided.

The layer thickness control blade 18 is made of a spring material such as phosphor bronze. The tip of the toner carrying roller 14 is moved by the elastic force of the spring material.
It is attached so as to press the surface.

The rotation of the toner carrying roller 14, the supply roller 12 and the agitator 17 is controlled by the CPU 13.
Is governed and controlled by

Next, control of each electrode during image formation will be described.

As shown in FIG. 1, the control voltage application circuit 8 connected between the control electrode 4 and the supply roller 12
Under the control of the CPU 13, each control electrode 4 is controlled based on an image signal sent from an external image signal output device (not shown).
-10V or + 35V is individually applied to each of them. Here, as the image signal output device (not shown), for example, an external computer or an image reading device for reading an image to be recorded can be connected.

Further, the back electrode plate 22 and the supply roller 12
And the back voltage applying circuit 24 connected between the
Under the control of U13, + 1k is always applied to back electrode plate 22.
A voltage of V is applied.

The thinned toner 16 carried on the toner carrying roller 14 (layer thickness controlling blade 18)
The toner carrier roller 14 is conveyed toward the electrode array 1 while being carried on the surface of the toner carrier roller 14 with the rotation of the toner carrier roller 14 in the direction A in FIG. Then, the transported toner 16 is supplied under the aperture 6 while being rubbed by the insulating sheet 2 of the electrode array 1.

At this time, the control voltage application circuit 8 applies a voltage of +35 V to the control electrode 4 corresponding to the position of the image in the image signal in response to the image signal. As a result, the apertures 6 on both sides of the control electrode 4 to which the voltage is applied move from the control electrode 4 toward the toner carrying roller 14 due to the potential difference between the control electrode 4 and the toner carrying roller 14 (grounded). Lines of electric force are formed. Accordingly, the negatively charged toner 16 being conveyed to the aperture 6 receives an electrostatic force in the direction of higher potential, passes through the aperture 6 from the toner carrying roller 14 and is drawn out to the control electrode 4 side. After that, the extracted toner 16 is
The back voltage applying circuit 24 flies toward the recording paper 20 by the electric field formed between the recording paper 20 and the electrode array 1 by the voltage of +1 kV applied to the back electrode plate 22, and Attach to form pixels.

On the other hand, since a voltage of 110 V is applied from the control voltage application circuit 8 to the control electrode 4 corresponding to the non-image portion in the image signal, the toner carrying roller 14 and the control corresponding to the non-image portion are controlled. Since no electric field is formed between the electrode 4 and the toner 16 on the toner carrying roller 14, no electrostatic force is applied, so that the toner 16 does not pass through the aperture 6, No pixel is formed in a portion corresponding to the control electrode 4 corresponding to.

When pixels for one scan of an image signal are formed on the surface of the recording sheet 20 by the toner 16, the transport roller 19 rotating in the direction D in FIG. 1 and the direction in the direction E in FIG. The rotating fixing device 26 transports one pixel in a direction perpendicular to the longitudinal direction of the electrode array 1 (a direction perpendicular to the aperture row formed by the apertures 6). By repeating the image forming process described above, a toner image is formed on the entire surface of the recording paper 20.

Thereafter, the formed toner image is transferred to the transport unit 1
The sheet 9 is conveyed to a fixing device 26 and fixed on the recording paper 20. The fixing device 26 may be of a pressure fixing type in addition to the heat fixing type.

Next, the thinning of the toner layer according to the present invention during non-image formation (ie, removal of unevenness of the toner layer caused by contact between the electrode array 1 and the toner carrying roller 14 during image formation) The operation for this will be described with reference to FIG.

When the toner layer is thinned during non-image formation, as shown in FIG. 3, the arm 7a rotates clockwise by a predetermined amount from the position shown in FIG. When the arm 7b rotates a predetermined amount counterclockwise from the position shown in FIG.
Are deformed so as to protrude leftward in FIG. 3, whereby the pressure contact state between the electrode array 1 and the toner carrying roller 14 is released. Then, in this state, the CPU 13 controls the toner carrying roller 14, the supply roller 12, and the agitator 1
7 are rotated in the respective directions to be rotated at a higher speed than during normal image formation.

By this operation, the old toner layer on the toner carrying roller 14 is peeled off by the supply roller 12 (the toner layer is removed by the rotation of the supply roller 12 and the toner carrying roller 14 in the opposite direction in the contact direction). Stripping), supply of new toner 16 and formation of the toner layer are performed, and the layer thickness of the toner layer is controlled by the layer thickness control blade 18.
The layer thickness of the upper toner layer is made uniform.

On the other hand, in the storage section 21, since the agitator 17 is rotating at a higher speed than usual, when new toner 16 is supplied, the new toner 16 is supplied to the toner carrying roller 14 and the supply roller 14. It adapts quickly and the charge amount is also made uniform.

The timing at which the above-described thinning of the toner layer (removal of unevenness in the toner layer) is performed may be performed, for example, periodically every several days, or in the image forming apparatus. It may be executed immediately after the power of S is turned on.

It is not necessary to always execute the adjustment of the new toner by the high-speed rotation of the agitator 17 together with the high-speed rotation of the toner carrying roller 14 and the supply roller 12, and the new toner 16 is supplied to the storage section 21. Only the execution may be performed.

In the case of an image forming apparatus in which the gap between the electrode array 1 and the back electrode plate 22 is small, the back electrode plate 22 is interlocked with the rotation of the arms 7a and 7b.
Is preferably retracted rearward (to the left in FIG. 3). With this configuration, a space necessary for separating the electrode array 1 from the toner carrying roller 14 is secured.

As described above, according to the operation of thinning the toner layer in the image forming apparatus S of the first embodiment,
Since the toner carrier roller 14 and the supply roller 12 are rotated while separating the electrode array 1 from the toner carrier roller 14 so that the toner 16 does not contact the back surface of the electrode array 1, the electrode array 1 is in contact. Accordingly, even if the toner layer on the toner carrying roller 14 is uneven, the unevenness can be removed by the supply roller 14 and the layer thickness control blade 18 after the contact between the electrode array 1 and the toner 16 is released.

Further, the electrode array 1 and the toner carrying roller 14 are periodically separated from each other,
When the supply roller 14 is rotated, the unevenness of the toner layer can be periodically removed.

Further, if the thickness of the toner layer is reduced when the power of the image forming apparatus S is turned on, the unevenness that occurs immediately after the power is turned on can be eliminated.

Further, since the toner carrying roller 14 and the supply roller 12 are operated at a higher speed when the toner layer is made thinner than in the normal operation, the above-mentioned unevenness can be removed more quickly and the image formation can be performed more quickly. Can be resumed.

When the toner layer is thinned with the high speed rotation of the agitator 17 when the new toner 16 is replenished, the replenished new toner 16 can be quickly supplied to the toner carrying roller 14 and the supply roller 12. You can adapt to.

Further, the electrode array 1 is formed of an elastic dielectric sheet 2, and the electrode array 1 is separated from the toner carrying roller 14 by bending the electrode array 1 by the arms 7a and 7b. So
The electrode array 1 and the toner carrying roller 14 can be separated from each other with a simple configuration, and the configuration of the entire image forming apparatus S can be simplified.

Further, by performing the above-mentioned thinning of the toner layer, unevenness in the toner can be removed.
An image corresponding to the recording information can be clearly formed on the recording paper 20.

(II) Second Embodiment Next, a second embodiment which is another embodiment of the present invention will be described with reference to FIGS. Here, FIG. 4 is a longitudinal sectional view of the image forming apparatus S ′ of the second embodiment, and is a longitudinal sectional view showing a state at the time of image formation in which the electrode array 1 and the toner carrying roller 14 are in contact. 5 is a vertical cross-sectional view of the image forming apparatus S ', showing a non-image forming state in which the electrode array 1 is separated from the toner carrying roller 14 and the rollers and the agitator 17 are idled together with the toner. It is. In addition, in each drawing, the same members as those of the first embodiment are denoted by the same member numbers, and detailed description of the operation and the like is omitted.

In the image forming apparatus S of the first embodiment described above, the arms 7a and 7b are rotated to
The electrode array 1 is separated from the toner carrying roller 14 by bending the electrode array 1. However, in the second embodiment, the electrode array 1 is moved together with its supporting portion instead of deforming the electrode array 1 in the second embodiment. The array 1 and the toner carrying roller 14 are separated from each other.

As shown in FIG. 4, in the image forming apparatus S ′ according to the second embodiment, both ends of the electrode array 1 in the short direction are formed so as to surround the toner case 11.
It is fixed to a holder 37 which can be moved in the left-right direction in FIG. 4 under the control of U13.

During image formation, as shown in FIG. 4, the holder 37 moves rightward in FIG. 4, and the electrode array 1 is pressed against the toner carrying roller 14 so that the recording paper 20 is pressed.
Is executed. The operation of the members other than the holder 37 during the image formation is described in the first section above.
Since this is the same as the embodiment, the detailed description is omitted.

On the other hand, when non-image formation is being performed and the toner layer is to be thinned, the holder 37 moves to the left in FIG. 5 as shown in FIG. 14. Then, at the same time, the toner carrying roller 14, the supply roller 12 and the agitator 17 are rotated at a high speed to execute the thinning of the toner layer and the adaptation of the new toner 6.

In the case of an image forming apparatus in which the gap between the electrode array 1 and the back electrode plate 22 is small, the back electrode plate 22 also moves rearward (see FIG.
It is desirable to adopt a configuration of retracting in the middle left direction). When the holder 37 moves leftward in FIG. 5, the back electrode plate 22 is also retracted leftward in FIG. 5, so that a space necessary for the electrode array 1 to be separated from the toner carrying roller 14 is provided. It is necessary to secure.

As described above, according to the operation of thinning the toner layer in the image forming apparatus S ′ of the second embodiment, the effect of the thinning of the toner layer in the image forming apparatus S of the first embodiment is obtained. In addition, the holder 37 for supporting the electrode array 1 is moved in a direction in which the electrode array 1 and the toner carrying roller 14 are separated from each other, whereby the electrode array 1 is moved.
And the toner carrying roller 14 are separated from each other.
And the toner carrying roller 14 are separated from each other, so that the toner layer can be thinned.

In the above-described first and second embodiments, the electrode array 1 is released from the pressure-contact state by separating the electrode array 1 from the toner carrying roller 14.
The electrode array 1 is fixed to the image forming apparatus S, and the toner carrying roller 14 and the supply roller 12 and the agitator 1
Alternatively, the entire toner supply device 10 including the toner supply device 7 may be configured to be movable, and the toner supply device 10 may be moved to release the pressure contact state between the electrode array 1 and the toner carrying roller 14.

[0087]

As described above, according to the first aspect of the present invention, the toner carrier is separated from the electrode array so that the toner is not in contact with the back surface of the electrode array. In addition, since the toner supply unit is operated, even if the toner layer on the toner carrier is uneven due to the contact of the electrode array, the toner supply unit and the layer thickness are released after the contact between the electrode array and the toner is released. The unevenness can be removed by the control blade.

Therefore, an image can be formed on the recording medium by flying the toner having a uniform layer thickness, so that a clear image can be formed.

According to the invention described in claim 2, according to claim 1
In addition to the effects of the invention described in the above, in addition to separating the electrode array and the toner carrier every predetermined period and operating the toner carrier and the toner supply body, irregularity of the toner layer is periodically reduced. Can be removed.

Therefore, the state of the toner layer capable of forming a clear image can be maintained.

According to the third aspect of the present invention, the first aspect
Or in addition to the effect of the invention described in 2 above, when power is supplied to the image forming toner supply device, the electrode array and the toner carrier are separated from each other, and the toner carrier and the toner supplier are operated. It is possible to remove the unevenness that occurs immediately after the power is turned on.

According to the invention described in claim 4, according to claim 1
In addition to the effects of the invention described in any one of the above-described items 3, the toner carrier and the toner supply member are operated at a higher speed than in the normal operation when the electrode array and the toner carrier are separated from each other. The unevenness can be quickly removed, and image formation can be quickly resumed.

According to the invention set forth in claim 5, claim 1 is provided.
In addition to the effects of the invention described in any one of to 4, since the electrode array is separated from the toner carrier when the new toner is supplied, the toner carrier, the toner supply body, and the storage unit are operated, The replenished new toner can be quickly applied to the toner carrier and the toner supply.

Therefore, the image forming toner supply device can be quickly brought into a state in which an image can be formed.

According to the invention described in claim 6, according to claim 5,
In addition to the effects of the invention described in the above, when the electrode array and the toner carrier are separated from each other, the toner carrier, the toner supply body and the storage means are operated at a higher speed than in the normal operation. The toner can be more quickly applied to the toner carrier and the toner supplier.

According to the invention of claim 7, according to claim 1,
7. In addition to the effects of the invention described in any one of the above-mentioned items 6, the dielectric substrate is an elastic body and the electrode array is separated from the toner carrier by bending the dielectric substrate. And the configuration of the entire image forming toner supply device can be simplified.

According to the invention as set forth in claim 8, according to claim 1,
7. In addition to the effects of the invention described in any one of 6 to 6, the electrode array and the toner carrier are moved by moving the support portion supporting the electrode array in a direction in which the electrode array and the toner carrier are separated from each other. Since the body is separated from the body, the electrode array can be separated from the toner holding means without applying a load to the electrode array.

Therefore, it is possible to form a clear image while extending the life of the electrode array.

According to the ninth aspect of the present invention, the first aspect is provided.
In addition to the effects of the invention described in any one of Items 1 to 8, it is possible to form an image corresponding to recording information clearly on a recording medium by removing unevenness in the toner layer.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view illustrating a configuration of an image forming apparatus according to a first embodiment.

2A and 2B are diagrams illustrating a configuration of an electrode array, FIG. 2A is an external perspective view of the electrode array, and FIG. 2B is a cross-sectional view illustrating a relationship between the electrode array and a toner carrying roller.

FIG. 3 is a longitudinal sectional view illustrating a configuration when the toner layer is thinned in the image forming apparatus according to the first embodiment.

FIG. 4 is a longitudinal sectional view illustrating a configuration of an image forming apparatus according to a second embodiment.

FIG. 5 is a longitudinal sectional view illustrating a configuration when a toner layer is thinned in an image forming apparatus according to a second embodiment.

6A and 6B are diagrams showing a configuration of a conventional image forming apparatus, in which FIG. 6A is a longitudinal sectional view, and FIG. 6B is a sectional view showing a relationship between an electrode array and a toner carrying roller.

[Explanation of symbols]

 1, 101: Electrode array 2: Insulating sheet 4, 104: Control electrode 6, 106: Aperture 7a, 7b: Arm 7c, 7d: Shaft 8, 108: Control voltage application circuit 9a, 9b: Friction reducing unit 10: Toner Supply device 11 Toner case 12, 112 Supply roller 13 CPU 14, 114 Toner carrying roller 16, 116 Toner 17 Agitator 18, 118 Layer thickness control blade 19 Transport rollers 20, 120 Recording paper 21 Storage units 22, 122: Back electrode plate 24, 110: Back voltage applying circuit 26: Fixing device 26a: Pressure roller 26b: Heat roller 30: Flat surface 32: Central axis 37: Holder S, S ', 100: Image forming device

Claims (9)

[Claims] 1. A plurality of openings through which a charged toner passes, and a plurality of control electrodes arranged at positions corresponding to the respective openings, the plurality of control electrodes for controlling the passage of the toner. An electrode array formed on a dielectric substrate, and the toner is carried on the front surface, and the toner is brought into contact with the back surface of the surface of the dielectric substrate on which the control electrodes are formed, and the opening is formed in the opening. A toner carrier for supplying toner, a toner supplier for supplying the toner to the toner carrier, a layer thickness control blade for controlling a layer thickness of the toner carried on the toner carrier, By applying a voltage to each of the electrodes independently based on recording information to be recorded on the recording medium, the toner is selectively passed onto the recording medium from the toner carrier through the opening. An image forming toner supply device comprising: a control electrode driving unit that reaches the recording medium and forms an image corresponding to the recording information on the recording medium. Separating means for preventing the toner carrier from contacting the back surface of the electrode array; and operating means for operating the toner carrier and the toner supply member in a state where the toner on the toner carrier is not in contact with the back surface. An image forming toner supply device, comprising: 2. The image forming toner supply device according to claim 1, wherein the separating unit separates the electrode array and the toner carrier at predetermined intervals, and the operating unit includes the operating unit. An image forming toner supply device, wherein the toner carrier and the toner supplier are operated when the electrode array is separated from the toner carrier. 3. The image forming toner supply device according to claim 1, wherein the separation unit connects the electrode array and the toner carrier when power is supplied to the image forming toner supply device. The image forming toner supply device, wherein the operating unit activates the toner carrier and the toner supply unit when the electrode array is separated from the toner carrier. 4. The image forming toner supply device according to claim 1, wherein the operating unit is configured to move the toner carrier when the electrode array is separated from the toner carrier. And an image forming toner supply device which operates the toner supply body at a higher speed than in a normal operation. 5. The image forming toner supply device according to claim 1, further comprising: a storage unit that stores the toner and supplies the toner to the toner supply unit. When the storage unit is replenished with the toner, the electrode array is separated from the toner carrier; and the operating unit is configured to carry the toner when the electrode array is separated from the toner carrier. An image forming toner supply device, wherein the toner supply member and the storage means are operated. 6. The image forming toner supply device according to claim 5, wherein the operating unit is configured to move the toner carrier, the toner supplier, and the toner carrier when the electrode array is separated from the toner carrier. An image forming toner supply device, wherein the storage means is operated at a higher speed than during normal operation. 7. The image forming toner supply device according to claim 1, wherein the dielectric substrate is an elastic body, and the separating unit bends the dielectric substrate. An image forming toner supply device, wherein the electrode array is separated from the toner carrier. 8. The image forming toner supply device according to claim 1, wherein the separation unit includes a support unit that supports the electrode array.
An image forming toner supply device, wherein the electrode array is separated from the toner carrier by moving the electrode array and the toner carrier in a direction in which the toner carrier is separated. 9. An image forming toner supply device according to claim 1, wherein the image forming toner supply device is disposed to face the electrode array with the recording medium interposed therebetween, and a voltage applied to each of the control electrodes is provided. A back electrode that assists the toner to reach the recording medium by applying a voltage corresponding to the application; and heating and pressurizing the recording medium to which the toner has reached and adhered, thereby applying the toner to the recording medium. An image forming apparatus comprising: a fixing unit that fixes toner; and a conveyance unit that conveys the recording medium from a position of the electrode array to the fixing unit.