JPH0557947A - Image forming device - Google Patents

Abstract

PURPOSE:To make a device small in size, the cost low, and form highly precise images. CONSTITUTION:On a driver substrate 1a consisting of a rigid substrate, a wiring pattern consisting of a plurality of signal lines is printed. On the center of the driver substrate 1a, a conductor exposed part 1b which is an exposed part of the wiring pattern not covered with a cover film is provided in the longitudinal direction. A recording electrode 1 is driven by a recording electrode driver 1c arranged on both sides of the conductor exposed part 1b on the driver substrate 1a. Adjacently to the downstream of the conductor exposed part 1b in toner conveying direction, a protrusion 1d is provided so as to accumulate toners between the conductor exposed part 1b and a recording sheet 5.

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 such as a printer or a display device which forms an image by electrostatically adhering a colored developer having conductivity and magnetism onto a recording medium.

[0002]

2. Description of the Related Art Conventionally, a device of this type has
It is known that an image is formed by the method described in Japanese Patent Publication No. 51-46707. As shown in FIG. 6, the conductive / magnetic toner 50 is conveyed by a rotating magnet 51 onto a non-magnetic cylinder (hereinafter simply referred to as “sleeve”) 52 and passes over a recording electrode 53 made of a magnetic material. Let And an insulating layer on the surface
By applying a voltage between the recording layer 53 and the conductive layer 54b of the recording medium 54, which is formed by sequentially stacking 54a and the conductive layer 54b,
The toner 50 is attached to the insulating layer 54a to form an image.

There is an image forming apparatus as shown in FIG. 7 as an example of a product actually manufactured by using such a method. In this, the conductive / magnetic toner 50 contained in the developing container is attached to the outer peripheral surface of the sleeve 52 and conveyed by a rotating magnetic field formed by a rotating magnet 51 concentric with the sleeve 52. Then, when the toner 50 passes through the recording electrode 53 provided on the outer peripheral surface of the sleeve 52 and is in physical contact with the recording medium 54 provided near the sleeve 52, the recording control unit 55 By applying a voltage to the recording electrode 53 and injecting an electric charge into the recording medium 54, the toner 50 is electrostatically attached to display an image. For example, when the signal voltage from the recording control unit 55 is applied + 40V, the toner 50
Is adhered to the recording medium 54 and is not adhered at 0 V to form an image.

[0004]

However, in the case of using the flexible printed circuit board as the recording electrode 53 in the above-mentioned conventional example, since the toner 50 is adhered onto the sleeve 52, the toner 50 passes through the flexible printed circuit board. A through hole is required. This caused the following problems. First, since the toner through hole cannot be made sufficiently large, the amount of toner 50 passing through is limited, and the recording electrode
Since the toner 50 is not sufficiently conveyed to 53, the image density may be reduced or image unevenness may occur. When the recording electrode 53 is formed on the flexible printed board, the flexible recording electrode 53 is likely to have irregularities when it is attached to the outer peripheral surface of the sleeve 52, and the linearity of the image is reduced particularly in the case of horizontal line printing. .. Further, it is not possible to mount the drive element of the recording electrode 53 on the flexible printed board from the viewpoint of bonding strength, and therefore it must be mounted on a rigid board such as glass epoxy resin. At this time, the flexible printed circuit board and the rigid circuit board have to be adhered to each other, and if the fine pitch wirings are adhered to each other, the assembling workability becomes poor and the cost becomes high.

An apparatus for mounting the recording electrode 53 and its driving element on a rigid substrate is disclosed in JP-A-59-104957.
Although it is disclosed in Japanese Laid-Open Patent Publication No. 59-104958, it cannot be wound around the outer peripheral surface of the sleeve 52, so that there are the following problems. First, since a certain magnetic force is required for the toner 50 to be conveyed on the sleeve 52, the rigid substrate must be made as small as possible in order to maintain the magnetic force on the rigid substrate, or the sleeve 52 and the rotating member must be rotated. The diameter of the magnet 51 must be increased so that the magnetic force acts on the rigid substrate. When making the rigid substrate small, it is necessary to make the driving element small and make the wiring pitch of the recording electrodes 53 finer.
It is not suitable for devices such as printers and displays that print 16 lines. Further, when the diameters of the sleeve 52 and the rotary magnet 51 are increased, it is difficult to reduce the size of the device, and since the weight of the rotary magnet 51 is heavy, a large rotational torque is required and power consumption increases. There was a risk of high costs.

The present invention has been made to solve the above-mentioned problems of the prior art, and an object of the present invention is to reduce the size and cost of the apparatus and enable high-definition image formation. is there.

[0007]

A typical means for solving the above-mentioned problems of the prior art and applied to the embodiments described below is on a rigid substrate for applying a voltage to a developer according to image information. A recording electrode disposed on a rigid substrate for applying a signal voltage corresponding to image information to the recording electrode, and a recording medium for forming an image by adhering the developer. And a developer supply unit for supplying a developer between the recording electrode and the recording medium,
The driving means is disposed on both sides of the exposed conductor portion of the recording electrode on the rigid substrate, and the protrusion portion is formed on the downstream side of the exposed conductor portion in the developer conveying direction.

[0008]

According to the above construction, the driving means is arranged on both sides of the exposed conductor of the recording electrode provided on the rigid substrate, and the protrusion is formed on the downstream side of the exposed conductor of the recording electrode in the developer conveying direction. As a result, the developer conveyed on the rigid substrate can be blocked between the exposed conductor portion of the recording electrode and the recording medium and accumulated more.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an image forming apparatus to which the present invention is applied will be described below with reference to the drawings. In this embodiment, a case where a display device is applied as an image forming apparatus will be described. 1 is a sectional view showing an essential part of an image forming apparatus and an explanatory view of recording electrodes, FIG. 2 is a comparative explanatory view of a conventional image forming apparatus, FIG. 3 is a sectional explanatory view showing a schematic configuration of the image forming apparatus, and FIG. FIG. 3 is a cross-sectional explanatory diagram showing the configuration of a recording medium.

First, the schematic structure of the display device will be described with reference to FIGS. 3 and 4. In FIG. 3, reference numeral 1 denotes a recording electrode arranged on a rigid substrate 1a for applying a voltage to a developer according to image information, and a recording electrode driver 1 which is also a driving means provided on the rigid substrate 1a.
It is driven by c to apply a signal voltage according to image information. On the rigid substrate 1a, a conductor exposed portion 1b which has a conductor portion exposed and contributes to recording is provided in the central portion, and recording electrode drivers 1c are arranged on both sides thereof.

Reference numeral 2 denotes a non-magnetic cylinder (hereinafter referred to as "sleeve") which constitutes a developer conveying means, and a rotary magnet 3 is rotatably provided inside thereof. By the alternating magnetic field formed by rotating the rotating magnet 3 in the clockwise direction, the toner 4 as the conductive / magnetic developer is transferred to the sleeve 2
Is conveyed in the counterclockwise direction on the peripheral surface of.

In the vicinity of the recording electrode 1, an endless belt-shaped recording sheet 5 which is a recording medium for adhering the toner 4 to form an image is arranged with a part thereof in close proximity. The recording sheet 5 is stretched around a conveyance roller 6 which is a conveyance means and which is arranged in a pair in the upper and lower directions. The conveying roller 6 is rotationally driven by a drive motor (not shown), and conveys the recording sheet 5 in the direction of arrow A in FIG.

The recording sheet 5 is, as shown in FIG.
Surface layer 5 made of plastic resin such as butyral resin, acrylic resin, nylon resin, polyester resin
a, a white layer 5b made of a plastic resin and titanium oxide, aluminum oxide, tin oxide / indium oxide, etc.
It is configured by polymerizing a conductive layer 5c vapor-deposited with aluminum or ITO (oxide of indium and tin) for imparting conductivity, and a base material 5d made of a plastic resin such as polyethylene terephthalate resin, polyethylene or polypropylene. There is. Further, a part of the conductive layer 5c is provided with a conductive portion 5e made of carbon paste for connecting to the ground via a resistor. Surface layer 5
a and the white layer 5b are electrically insulated, and the white layer 5
As b, an inorganic substance such as titanium oxide (TiO ₂ ) or aluminum oxide (AlO ₃ ) is used in order to produce white as a base color of the screen.

The structure of each part will be exemplified below. The surface layer 5a has a thickness of 1 to 20 μm, preferably 1 to 5 μm, and a volume resistance value of 10 ⁷ to 10 ¹⁶ Ωcm, preferably 10 ⁹ to 10 ¹³ Ωc.
m, the thickness of the white layer 5b is 5 to 30 μm, preferably 5 to 10 μm
m, the volume resistance value is 10 ⁰ to 10 ⁷ Ωcm, preferably 10 ⁰ to
10 ⁵ Ωcm, the thickness of the conductive layer 5c is 800 to 1000 Å, the volume resistance value is 10 ⁰ to 10 ² cm, and the thickness of the substrate 5d is 70 to 300 μ.
m, the thickness of the conductive part 5e is 10 to 100 μm, and the volume resistance value is 10
It is composed of ⁰ to 10 ³ Ωcm. The toner 4 has a volume resistance value of 10 ³ to 10 ⁹ Ωcm, an average volume particle size of 8 to 15 μm, preferably 10 to 12 μm, and a composition of a plastic resin such as acrylic resin, nylon resin, polyethylene or polypropylene. Carbon 1 to 10% (weight ratio) and ferrite 40 to 70% (weight ratio) were used.

Reference numeral 7 is an image display unit for displaying the image formed on the recording sheet 5 to the outside. Recording sheet 5
The toner 4 attached by the electrostatic force passes through the image display unit 7 made of glass to display an image, and then is conveyed again into the developing container 8.

Reference numeral 9 denotes a cleaning member for scraping off the toner 4 after the image is displayed on the developing container 8. The cleaning member 9 scrapes off the toner 4 by rubbing a brush made of plastic resin or the like against the recording sheet 5, and is supported by the apparatus body frame 10. The toner 4 scraped off by the developing container 8 is conveyed again along the sleeve 2 in preparation for the next image formation. Reference numeral 11 is a support member provided to face the cleaning member 9 to support the recording sheet 5. Further, 12 is a magnet for collecting the toner 4 so that it can be easily scraped off.

The structure of the recording electrode 1 will be described with reference to FIG. A wiring pattern composed of a plurality of signal lines is printed on a driver substrate 1a made of a rigid substrate such as glass epoxy resin.
At the center of a, a conductor exposed portion 1b is provided in the longitudinal direction in which a part of the wiring pattern is exposed without being covered by the cover film. The recording electrodes 1 are driven by recording electrode drivers 1c provided on both sides of the exposed conductor portion 1b. Further, on the driver substrate 1a, a protruding portion 1d is provided in the vicinity of the downstream side of the conductor exposed portion 1b in the toner conveying direction.
Is provided. The conductor exposed portion 1b and the recording sheet 5
The height of the protrusion 1d from the driver substrate 1a is 100 μm to 800 so that more toner 4 is accumulated between
It is adjusted to about μm.

In the present embodiment, the exposed width of the conductor exposed portion 1b is set to 1.5 mm to 4 mm, and the sleeve 2
The magnetic flux density at the point B of the driver substrate 1a farthest from the peripheral surface was 100 to 300 Gauss, and there was no problem in the toner transportation when the toner 4 was transported. To give concrete values of other components, the outer diameter of the sleeve 2 is 20 mm, the material is SUS316, 304 stainless steel, the outer diameter of the rotary magnet 3 is 18 mm, the maximum magnetic flux density is 1500 to 2000 Gauss, and the driver substrate is The size of 1a is 1mm (thickness) x 25mm
It was (width) × 210 mm (length).

On the other hand, when the conductor exposed portion 1b forming the recording electrode 1 is provided at the end of the driver substrate 1a as shown in FIG.
If the recording electrode 1 of 8 lines / mm is to be formed, the width of the driver substrate 1a becomes about 25 to 30 mm. When this is mounted on the sleeve 2 having an outer diameter of 20 mm, the point C indicating the place where the recording electrode driver 1c is provided on the driver substrate 1a is separated from the outer peripheral surface of the sleeve 2 and the magnetic force is reduced, so that the toner 4 is removed. It may not be transported.

According to the above construction, since the recording electrode 1 is provided with the conductor exposed portion 1b in the central portion of the driver substrate 1a and is driven by the recording electrode drivers 1c arranged on both sides thereof, the outer diameter of the sleeve 2 is reduced. It becomes possible to arrange even if the size becomes small, and it is possible to cope with the size and weight reduction of the device. Further, since the protrusion 1d provided on the downstream side of the conductor exposed portion 1b in the toner conveying direction can sufficiently accumulate the toner 4 between the conductor exposed portion 1b and the recording sheet 5, high-definition image formation is performed. be able to.

Next, another structure of the recording electrode 1 will be described with reference to FIG. In this embodiment, the sleeve 2 has two
A driver substrate 1a made of a glass epoxy resin or the like is arranged and connected by a flexible substrate 1e made of a heat-resistant polyimide resin or the like, and a wiring pattern is printed on the flexible substrate 1e. The conductor exposed portion 1b is provided in the central portion. The flexible substrate 1e has a curved central portion provided with the conductor exposed portion 1b and is close to the recording sheet 5, so that the toner 4 can be sufficiently accumulated between the both. Therefore,
Since the toner 4 after recording is configured to be separated from the recording sheet 5 along the flexible substrate 1e, the protrusion 1d shown in the above embodiment is omitted. With such a configuration, the same effect as that of the above-described embodiment can be obtained.

[0022]

As described above, according to the present invention, the recording electrode is provided with the conductor exposed portion in the center of the rigid substrate and is driven by the driving means arranged on both sides of the conductor exposed portion. The non-magnetic cylinder can be arranged even if the outer diameter of the non-magnetic cylinder becomes small, and the apparatus can be made smaller and lighter. Further, since the protrusion provided on the downstream side of the exposed conductor portion in the developer conveying direction can sufficiently accumulate the developer between the exposed conductor portion and the recording medium, high-definition image formation can be performed. ..

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a main part of an image forming apparatus and an explanatory view of recording electrodes.

FIG. 2 is a comparison explanatory view of a conventional image forming apparatus.

FIG. 3 is a cross-sectional explanatory diagram illustrating a schematic configuration of an image forming apparatus.

FIG. 4 is an explanatory cross-sectional view showing the configuration of a recording medium.

FIG. 5 is a cross-sectional explanatory view showing another example of the recording electrode.

FIG. 6 is a cross-sectional explanatory view showing a conventional image forming principle.

FIG. 7 is a cross-sectional explanatory view showing a conventional image forming apparatus.

[Explanation of symbols]

1 is a recording electrode, 1a is a driver substrate, 1b is a conductor exposed portion, 1c is a recording electrode driver, 1d is a protruding portion, 1e is a flexible substrate, 2 is a sleeve, 3 is a rotating magnet, 4 is toner, 5 is a recording sheet, Reference numeral 5a is a surface layer, 5b is a white layer, 5c is a conductive layer, 5d is a base material, 5e is a conductive portion, 6 is a conveying roller, 7 is an image display portion, 8 is a developing container, 9 is a cleaning member, and 10 is an apparatus main body. A frame, 11 is a support member, and 12 is a magnet.

Claims (4)

[Claims] 1. A recording electrode arranged on a rigid substrate for applying a voltage to a developer according to image information, and a rigid substrate for applying a signal voltage according to image information to the recording electrode. A driving unit disposed, a recording medium for forming the image by adhering the developer, and a developer supplying unit for supplying the developer between the recording electrode and the recording medium, The image forming apparatus is characterized in that the driving means is arranged on both sides of the conductor exposed portion of the recording electrode on the rigid substrate, and a protrusion is formed on the downstream side of the conductor exposed portion in the developer conveying direction. 2. A recording electrode for applying a voltage to a developer according to image information, and a drive unit arranged on a rigid substrate for applying a signal voltage according to image information to the recording electrode, A recording medium for forming the image by adhering the developer, and a developer supplying unit for supplying the developer between the recording electrode and the recording medium, wherein the recording electrode is a rigid substrate. An image forming apparatus, wherein a conductor exposed portion is formed and provided on a flexible substrate to be connected. 3. The image forming apparatus according to claim 1, wherein the recording medium is formed by laminating a dielectric layer and a conductive layer. 4. The image forming apparatus according to claim 3, wherein the image formed on the recording medium is a display device that is used by being displayed on a display unit.