JPH08324017A - Recorder - Google Patents

Abstract

PURPOSE: To provide a low-cost image forming apparatus capable of forming an image of high quality without irregularity. CONSTITUTION: In an aperture electrode 1, a plurality of apertures 6 each having a diameter of 80μm are formed in one row on an insulating sheet 2 made of polyimide and having a thickness of 25μm, and a control electrode 4 having a thickness of 8μm is formed at the upper side of each aperture 6. A coating layer 5 having a thickness of 5μm is formed on the surface of the sheet 2 at the opposite side to the control electrode forming surface at both sides via each aperture 6 in a toner conveying direction, i.e., the contact part in contact with the toner 16 carried at least to toner carrying roller 14. Further, protrusions 7 each having a thickness of 5μm are formed at both sides perpendicular to the toner supplying direction of the aperture 6 integrally with the layer 5. The protrusions 7 press the toner 6 to be conveyed to supply mist-like toner 16 to the apertures 6.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording device applied to copying machines, printers, facsimiles and the like.

[0002]

2. Description of the Related Art Conventionally, as one of recording devices of this type,
An aperture electrode that has an opening and a control electrode provided around the opening, and applies a voltage to the control electrode to modulate and control the flow of toner passing through the opening corresponding to the control electrode. A body and a toner conveying device which is arranged on the back surface of the aperture electrode body and conveys charged toner to the opening of the aperture electrode body, and the toner conveying device conveys the charged toner and passes through the opening of the aperture electrode body. A recording apparatus has been proposed that includes a counter electrode that guides toner to a support disposed on the surface of the aperture.

However, in this recording apparatus, since the toner carried by the aperture electrode body is firmly adhered to the toner carrier in the toner carrier by the image force or the like, the toner flow can be controlled. could not.

Therefore, the applicant of the present invention has filed Japanese Patent Application Laid-Open No. 6-1557.
In Japanese Patent Laid-Open No. 98, there is proposed a recording apparatus in which the toner carrier and the aperture electrode body are arranged in contact with each other near the opening.

[0005]

However, in this conventional recording apparatus, when the aperture electrode body and the toner on the toner carrier slide in contact with each other, the toner is pressed against the aperture electrode body. In some cases, the toner transport may be delayed at the contact surface between the aperture electrode body and the toner carrier. That is, when the toner comes into contact with the aperture electrode body, the contact portion is charged and the toner stays there. When the toner stays, it becomes difficult to carry the toner to the downstream side of the staying toner in the toner carrying direction, the carrying state of the toner becomes unstable, and the toner may not be uniformly supplied to each aperture. is there. As a result, one opening (aperture)
A large amount of toner is conveyed to the other side, and the problem that no toner is conveyed to the other one opening (aperture) occurs, causing unevenness in the aperture arrangement direction in the output image, which is very unsightly. Was becoming.

The present invention has been made to solve the above-mentioned problems, and an object thereof is to provide a recording apparatus capable of forming an image of high quality without unevenness.

[0007]

In order to achieve this object, a recording apparatus according to claim 1 of the present invention has a plurality of charged particle passage portions for allowing passage of charged particles, and the plurality of charged particles. Charged particle control means having a plurality of control electrodes provided corresponding to each of the particle passage portions, and provided in the vicinity of the charged particle control means for conveying the charged particles to the plurality of charged particle passage portions. In a recording apparatus including the charged particle carrier, the charged particle carrier is provided on the charged particle carrier side of the charged particle control means, at least in an upstream portion in the carrier particle transport direction in the vicinity of the charged particle passage, and the carrier is transported to the charged particle carrier. And a protrusion for contacting the charged particles to be charged.

The recording apparatus according to a second aspect of the invention is provided with an antistatic layer which is provided on the upstream side of the projection in the carrying direction of the charged particles and which prevents the charged particles from being charged.

A recording apparatus according to a third aspect of the present invention includes a projection portion and an antistatic layer which are integrally formed of an antistatic material.

[0010]

In the recording apparatus according to claim 1 of the present invention having the above structure, the charged particle carrier transports the charged particles to the plurality of charged particle passage portions, and the protrusions are charged in the vicinity of the charged particle passage portions. The charged particles are brought into contact with the particles to press the charged particle carrier against the charged particle carrier, and the charged particles released in the charged particle passage portion float in the charged particle passage portion.

Further, in the recording apparatus according to the second aspect, the antistatic layer prevents the charged particles from being charged on the upstream side of the projecting portion in the conveying direction of the charged particles.

In the recording apparatus according to the third aspect, the protrusion and the antistatic layer are integrally formed of the antistatic material.

[0013]

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a diagram showing an outline of an image forming apparatus according to this embodiment. A cylindrical rear electrode having a gap of 1 mm above the aperture electrode body 1 as a charged particle control means. A roller 22 is rotatably supported by a chassis (not shown), and the back electrode roller 22 is rotationally driven in the clockwise direction in the figure by a conveyance motor. The shape of the back electrode roller 22 does not have to be cylindrical, and may be, for example, a plate-shaped back electrode.

An image forming medium (paper, paper,
When an OHP sheet or the like) 20 is inserted, the image forming medium 20 is conveyed leftward in FIG. 1 while keeping a predetermined gap with respect to the aperture electrode body 1.

On the lower side of the aperture electrode body 1,
A toner supply device 10 is arranged along the longitudinal direction of the aperture electrode body 1, and the toner is heated and melted at the destination of the image forming medium 20 conveyed by the back electrode roller 22. A fixing device 26 for fixing the toner 16 on the image forming medium 20 is provided.

Next, the respective constituent elements will be described in detail. The toner supply device 10 includes a toner case 11 which also serves as a housing of the entire device, and a toner 16 which is stored in the toner case 11 as charged particles. A supply roller 12 and a toner carrying roller 1 as a charged particle carrier
4 and a toner layer regulating blade 27. Here, the toner carrying roller 14 carries the toner 16 and conveys it toward the aperture electrode body 1, and the supply roller 12 is the toner carrying roller 1.
The toner 16 is supplied to the No. 4 toner.

The supply roller 12 and the toner carrying roller 14 are rotatably supported by the toner case 11 in the direction of the arrow in the figure, and they are arranged in parallel in contact with each other. The supply roller 12 and the toner carrying roller 14 are rotated by a drive motor in an interlocking manner. Further, the toner layer regulating blade 27 is used for the toner carrying roller 14
It is for adjusting the amount of the toner 16 carried on the roller 16 to be uniform on the roller surface and for uniformly charging the toner 16, and is pressed against the toner carrying roller 14.

As shown in FIGS. 2 and 3, the aperture electrode body 1 is formed by arranging a plurality of apertures 6 as a charged particle passage portion having a diameter of 80 μm on a 25 μm thick polyimide insulating sheet 2 in a row. The control electrode 4 is formed on the upper side of each aperture 6 with a thickness of 8 μm.
On the surface of the insulating sheet 2 opposite to the surface on which the control electrodes are formed (surface on the side of the toner carrying roller), the toner carried on both sides of each aperture 6 in the toner transport direction, that is, at least on the toner carrying roller 14 is held. A coating layer 5 as an antistatic layer having a film thickness of 5 μm is formed on a contact portion that contacts 16. Further, a protrusion 7 having a film thickness of 5 μm and a width of 5 μm is provided perpendicularly to the toner supply direction of the aperture 6.
Are provided on both sides. The thickness and width of the protrusion 7 need not be 5 μm and may be 30 μm or less, and are preferably integrally formed of the same antistatic material as the coating layer 5.

Next, the material will be described in detail.

As the antistatic material for the coating layer 5 and the protrusions 7, carbon is dispersed in an organic resin such as an epoxy resin or a polyimide resin, preferably a binder made of a polyimide resin to form a paint, which is used as an insulating sheet 2. Is applied by a screen printing method or the like to form a coating film, and then in an atmosphere of 300 ° C or lower, preferably 180 ° C to
It is a film that is baked and cured in an atmosphere of 280 ° C. for several minutes. Instead of carbon, aluminum, molybdenum,
Conductive fine particles such as nickel, chromium, and carbon can be used, but carbon is used here because it is inexpensive.

In the aperture electrode body 1, as shown in FIGS. 1 and 3, the control electrode 4 faces the image forming medium 20 side and the coating layer 5 faces the toner carrying roller 14 side.
Since the protrusions 7 are arranged so as to face each other, the protrusions 7 are arranged so as to come into contact with the toner 16 on the toner carrying roller 14 upstream and downstream of the position of the aperture 6 in the toner conveying direction. Further, the coating layer 5 may also come into contact with the toner 16 on the toner carrying roller 14, but the coating layer 5 is made of an antistatic material and does not charge the toner 16, so that the toner 16 stays there. There is no such thing.

A control voltage application circuit 8 is connected between the control electrode 4 and the toner carrying roller 14.
The control voltage applying circuit 8 inputs an image signal having a dot pattern developed from the outside, and turns on / off each control electrode 4 in response to on / off of each dot of a dot row of the dot pattern (voltage application of -20V or + 20V). Voltage application) is controlled, and this is performed in association with the rotational driving of the back electrode roller 22. In other words, when the flight control of the toner for one dot row is completed by the back electrode roller 22, the flight control of the toner for the next dot row is performed.

Further, a DC power source 24 is connected between the back electrode roller 22 and the toner carrying roller 14, and this DC power source is + with respect to the back electrode roller 22.
A voltage of 1 kV can be applied.

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

First, a brief description will be given. The toner 16 sent from the supply roller 12 is caused by the rotation of the toner carrying roller 14 and the supply roller 12 in the direction of the arrow in FIG.
Is rubbed against the toner carrying roller 14, is negatively charged, and is carried on the toner carrying roller 14.
The carried toner 16 is thinned and charged by the layer regulating blade 27, and then the toner carrying roller 1
It is conveyed toward the aperture electrode body 1 by the rotation of 4. Then, the toner on the toner carrying roller 14 is rubbed by the coating layer 5 of the aperture electrode body 1, further passes through the protrusion 7, and is supplied below the aperture 6.

Here, in accordance with the image signal, a voltage of + 20V is applied from the control voltage application circuit 8 to the control electrode 4 corresponding to the image portion (the ON portion of each dot of the dot row). . As a result, the control electrode 4 and the toner carrying roller 14 are provided near the aperture 6 corresponding to the image portion.
The electric potential line between the control electrode 4 and the toner carrying roller 14 is formed by the potential difference between the two. As a result, the negatively charged toner receives an electrostatic force in the direction of higher electric potential, passes through the aperture 6 from the toner carrying roller 14, and is drawn out to the control electrode 4 side. Toner 16 pulled out
Further flies toward the image forming medium 20 due to the electric field formed between the image forming medium 20 and the aperture electrode body 1 by the voltage applied to the back electrode 22, and is deposited on the image forming medium 20. Then, dot-shaped pixels are formed.

Further, a voltage of -20 V is applied from the control voltage applying circuit 8 to the control electrode 4 corresponding to the non-image part (the off part of each dot of the dot row). As a result, an electric force line toward the control electrode 4 is formed between the toner carrying roller 14 and the control electrode 4. Then, the negatively charged toner receives an electrostatic force to the side having a higher potential, so that the toner 16 on the toner carrying roller 14 does not pass through the aperture 6. That is, the toner does not fly.

Further, the image forming medium 20 is fed by one pixel in the direction perpendicular to the aperture row while the pixels arranged in one row by the toner 16 are formed on the surface of the image forming medium 20. Then, by repeating the above process, a toner image is formed on the entire surface of the image forming medium 20. After that, the formed toner image is transferred to the image forming medium 20 by the fixing device 26.
It is heat-fixed on top.

The feature of this process is that the toner 16 is pressed by the protrusion 7 on the upstream side in the toner conveying direction near the aperture 6, and the pressure is released at a stroke by the aperture 6. Therefore, the toner 16 is not in the state of being adhered to the toner carrying roller 14, but the protrusion 7
It feels like being flipped by, in a state of floating like a mist,
It is supplied to the aperture 6. As a result, the force exerted on the toner 16 floating in the air is released from the adhesive force with the toner carrying roller 14 or the like, and the Coulomb force due to the electric field in the aperture 6 becomes dominant. Therefore, it is possible to control the toner flow with a low voltage.

The present invention is not limited to the embodiments described in detail above, and various modifications can be made without departing from the spirit of the invention.

In this embodiment, the protrusions are provided by coating, but the insulating sheet itself may be provided with the protrusions.

Further, as shown in FIG.
However, it may be only on the upstream side of the aperture 46 in the toner supply direction.

Further, it is possible to provide the protrusion 57 around the aperture 56 as shown in FIG.

In the above embodiment, the aperture electrode body was used as the toner flow control means, but it is also possible to use, for example, a knitted electrode body as described in JP-A-1-503221. .

[0036]

As described above, according to the recording apparatus of the present invention, the charged particles are supplied to the charged particle passage portion in a mist-like floating state, not in a state of being attached to the charged particle carrier. Therefore, the charged particles can be uniformly supplied to the charged particle passage portion, and an image of high quality without unevenness can be formed.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of a recording apparatus according to an embodiment of the present invention.

FIG. 2 is a perspective view of an aperture electrode body mounted on the recording device.

FIG. 3 is a cross-sectional view of the aperture electrode body.

FIG. 4 is a cross-sectional view of a modified aperture electrode body mounted on the recording apparatus.

FIG. 5 is a back view of an aperture electrode body which is another modification mounted on the recording apparatus.

[Explanation of symbols]

 1 Aperture Electrode Body 3 Control Electrode 4 Aperture 5 Coating Layer 7 Protrusion 11 Toner Conveying Roller 16 Toner

Claims (3)

[Claims] 1. A charged particle control means having a plurality of charged particle passage portions for allowing the passage of charged particles and a plurality of control electrodes provided corresponding to the plurality of charged particle passage portions, respectively. A charged particle carrier for transporting charged particles to a plurality of charged particle passages, which is provided in the vicinity of the charged particle controller, the charged particle carrier side of the charged particle controller A recording apparatus, characterized in that it is provided with a protrusion provided at least in the vicinity of the charged particle passage portion in an upstream portion in the transport direction of the charged particles and for contacting the charged particles transported to the charged particle transport body. . 2. The recording according to claim 1, further comprising an antistatic layer provided on the upstream side of the protrusion in the carrying direction of the charged particles and for preventing the charged particles from being charged. apparatus. 3. The recording apparatus according to claim 2, wherein the protrusion and the antistatic layer are integrally formed of an antistatic material.