JPH05104771A - Image recording apparatus - Google Patents

Abstract

PURPOSE:To record a good image by supplying toner uniform in charge characteristics. CONSTITUTION:A charge member 2 is provided to the arranging surface of gate electrodes 22 of an aperture electrode 20. When toner is constituted of material quality easily susceptible to friction charge, the charge characteristics of the toner are homogenized by exciting the charge member 26 and, as a result, the well controlled recording of an image becomes possible.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image recording device,
More specifically, the present invention relates to a powder particle direct drive type image recording apparatus.

[0002]

2. Description of the Related Art Conventionally, in the specification and drawings attached to Japanese Patent Application No. 2-196781, an image is formed on an image receptor by selectively flying charged particles such as toner in an aperture electrode. Image recording devices have been proposed. In this apparatus, charged particles are controlled by an electric field formed on a recording electrode having an opening electrode, and at that time, vibration is applied so that the opening electrode is not clogged.

[0003]

However, the following problems have occurred in the image recording apparatus configured as described above. That is, the toner is charged and sent to the recording electrode that modulates with an electric field. At this time, the toner was not uniformly charged, but the opposite polarity toner was mixed.
Therefore, even if the control is performed by the electric field, there is a problem that the toner adheres to the image receiving body even when the flight is prohibited because the toner of the opposite polarity exists.

The present inventor has been investigating such problems by improving the charging method in a so-called toner supply system upstream of the recording electrode. However, it has been difficult to completely solve the problem by uniformly charging the toner only with the charging system.

The present invention has been made to solve the above-mentioned problems, and provides an image recording apparatus having excellent recording characteristics by satisfactorily controlling the chargeability of the toner supplied to the recording electrodes. Especially.

[0006]

To achieve this object, the image recording apparatus of the present invention has the following features. That is, this image recording apparatus is a direct control system in which charged particles are modulated by passing through a recording electrode having an opening and an image is recorded on an image receptor. Further, it is provided with a vibrating means for vibrating the recording electrode, and a charging member provided on at least a surface side of the recording electrode to which the charged particles are supplied and for frictionally charging the charged particles.

[0007]

The image recording apparatus of the present invention having the above structure is
Since the surface of the charging member is vibrating, the toner close to the surface of the charging member is triboelectrically charged. The charging member and the toner are repeatedly frictionally charged by the excited vibration, and the toner is further charged, and the charge amount is even. Thereby,
Toner with uniform charging characteristics is supplied to the opening of the recording electrode. As a result, the toner particles can be well controlled by the electric field, and excellent recording characteristics can be exhibited.

[0008]

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

FIG. 1 is a schematic sectional view of an image recording apparatus to which the present invention is applied. In FIG. 1, the image recording device 19 is
It comprises a recording unit 1 and a heat fixing unit 2. An insertion port 17 and an ejection port 18 are provided on the side of the image recording / recording device 19. In the recording unit 1, an image or the like is recorded on the medium P such as plain paper that has entered through the insertion slot 17. Then, in the heat fixing unit 2, the image or the like on this medium is fixed. Further, the medium P is sent to the ejection port 18 via the guide 15.

The recording unit 1 includes a rotatable brush roller 3
And an aperture electrode 20 and a counter electrode 12. The brush roller 3 is provided around the brush roller 3.
According to the rotation direction of the supply roller 4 and the layer thickness regulating member 1
1 and the scraping member 10 are respectively the brush roller 3
Is provided in contact with. The brush roller 3 is connected to the ground. Further, the supply roller 4 is covered with the toner case K. The toner T is stored inside the toner case K.

Above the brush roller 3, the aperture electrode 20 serving as a recording electrode is provided. here,
The aperture electrode will be described with reference to FIG. Figure 2
FIG. 4 is a perspective view of an aperture electrode. The aperture electrode 20 has a line electrode 21 and a gate electrode 22 arranged on both surfaces of a substrate 25, and a large number of apertures 24 and conductive wires 23 penetrating the both. The substrate 25 may be a flat plate-like insulator, and normally, a resin material such as polyimide having a thickness of about 25 to 100 μm or a ceramic material such as alumina or zirconia can be used. On the substrate 25, lines having a thickness of several microns or more and gate electrodes 21 and 22 provided by a printing method or a thin film forming method are provided.

A charging member 26 is provided on the surface having the gate electrode 22. The charging member 26 may be generally an insulating material, and the material may be selected according to positive and negative polarities. In this embodiment, since positively charged toner is used, it is preferable that the charging member 26 be negatively charged, and a fluorine compound, a silicon compound, or the like has good characteristics. If a positively charged material is required, nylon, polyacetal or the like may be used. The line and the gate electrode 21,
22 are connected to signal sources S1 and S2, respectively. Further, a vibrator 27 is provided below the aperture electrode 20. The vibrator 27 can vibrate by forming an electrode on a piezoelectric body such as PZT and applying an alternating voltage.

A transfer mechanism 30 as an intermediate support is arranged above the aperture electrode 20. Here, the transfer mechanism 30 will be described with reference to FIG. FIG. 3 is a perspective view of the transfer mechanism 30. The transfer mechanism 30 includes a pair of drive rollers 31 and a transfer belt 32. The drive roller 31 is connected to the negative power source E1 as shown in FIG. 1 and is rotatable counterclockwise in the figure.

Further, the counter electrode 12 is provided on the opposite side of the brush roller 3 with the aperture electrode 20 and the transfer mechanism 30 interposed therebetween, with a space between the counter electrode 12 and the transfer mechanism 30. A negative voltage lower than that of the transfer mechanism 30 is applied to the counter electrode 12 by the power source E2. Enter this space from the insertion slot 17,
The medium P sent via the guide 15 and the pair of auxiliary rollers 16 passes through. By applying this voltage, the toner T that has passed through the aperture 24 of the aperture electrode 20 is once placed on the transfer belt 32 and then moved and attracted to the medium P.

The heat fixing section 2 is composed of a heat roller 13 having a heat source and a press roller 14. And
The heat roller 13 and the press roller 14 are arranged so that the medium P can pass between them.

Next, the operation of the image recording apparatus using this embodiment will be described with reference to FIG.

The medium P inserted from the insertion port 17 is conveyed to the recording section 1. In the recording unit 1, the toner T is supplied to the brush roller 3 by the supply roller 4. At this time, the toner T is supplied to the supply roller 4 and the brush roller 3
While contacting with, rubbing, and in this embodiment, is charged positively (+). Toner T charged positively (+)
Are carried by the brush roller 3. Then, the layer thickness regulating member 11 scrapes off the toner T that is excessively supplied to the brush roller roller 3. As a result, a uniform toner layer is formed on the brush roller 3.

Then, in the vicinity of the aperture electrode 20,
The brush roller 3 is scratched by the scraping member 10. Then, due to elasticity, when the brush returns to its original position, the toner T carried by the brush in an appropriate amount jumps up. As a result, the toner T forms a cloud and is supplied to the aperture electrode 20. However, this toner cloud is not electrostatically uniform in charge polarity, and the charge amount is not uniform.

Transducer 2 installed on aperture electrode 20
7 is excited, and a surface wave is generated on the surface of the aperture electrode 20. That is, since the surface of the charging member 26 is displaced with an amplitude of about 0.3 μm, the charging member 2
The toner T near the surface of 6 is triboelectrically charged. The charging member 26 and the toner T are repeatedly frictionally charged by the excited vibration, and the toner T is further positively charged and the charge amount is also uniform. In this way, the toner T having the uniform chargeability is used as the aperture 2
4 is supplied.

The cloud of the toner T, which is positively (+) charged, is controlled to pass through the aperture 24 in which the flight electric field and the shield electric field are formed by the signal sources S1 and S2. That is, if the electric field is formed in a forward bias with respect to the toner charge, the toner flies to the counter electrode 12. If the electric field is formed in the reverse bias, the toner does not fly. The flying toner is transferred onto the transfer belt 3 to which a negative voltage is applied.
Go to 2.

As described above, since the toner T has uniform electrostatic characteristics, it is possible to ideally record according to the electric field formed by the aperture. That is, conventionally, when the opposite polarity toner is present, the control by the electric field is not effective, and an extra spot is formed. In addition, even if the gradation control is performed, the pixel density corresponding to the signal cannot be formed because the charge amounts are not uniform. However, according to the present invention, both characteristics can be homogenized, so that a very good image can be formed. In this way, the toner T reaches the transfer belt 32. The toner image formed on the transfer belt 32 is driven by the driving roller 31 and is carried to the surface facing the medium P. Here, the toner T is further electrostatically transferred to the medium P.

After that, the medium P is conveyed to the thermal fixing section 2. Then, at this place, the image on the medium P is fixed by being pressed into contact with the heat roller 13 and the press roller 14. Since this fixing method is a general method, detailed description thereof will be omitted. Then, finally, the image-formed medium P passes through the guide 15 and
It is conveyed to the take-out port 18 and taken out.

The present invention is not limited to the above-described embodiments, and can be modified within the scope of the invention. That is, the gist of the present invention is to dispose a charging member for frictionally charging the toner T on a part of the vibrating aperture electrode body. In this embodiment, the charging member is arranged only on the surface of the electrode. However, the toner may be charged more efficiently by exciting the inside of the path through which the toner flows, such as the toner case and the carrying roller.

[0024]

As is apparent from the above description, the toner having uniform charging characteristics is supplied to the opening of the recording electrode by the image recording apparatus of the present invention. As a result, the toner particles can be well controlled by the electric field, and excellent recording characteristics can be exhibited.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view showing the configuration of an image recording apparatus of this embodiment.

FIG. 2 is a perspective view of a recording electrode.

FIG. 3 is a perspective view of a transfer mechanism.

[Explanation of symbols]

 20 Aperture Electrode Section 21 Line Electrode 22 Gate Electrode 24 Aperture 25 Substrate 26 Charging Member

Claims (1)

[Claims] 1. An image recording apparatus of a direct control system, in which charged particles are modulated by passing through a recording electrode having an opening to record an image on an image receptor, a vibrating means for vibrating the recording electrode, An image recording apparatus comprising: a charging member, which is provided on at least a surface side of the recording electrode to which the charged particles are supplied, and which frictionally charges the charged particles.