JPH058433A - Image forming apparatus - Google Patents

Abstract

PURPOSE:To enhance image quality by feeding toner between a recording electrode and a recording medium and saving the space around the recording electrode of a recorder for forming a toner image on the medium. CONSTITUTION:A recording electrode 4 is mounted on a rigid board 17 fixed onto a tubular member 3 for carrying toner. In order to save the space around the recording electrode, electric components 19b to be arranged on the board are fixed in a space 22 formed by the board and the tubular member. Since the electrode is downsized, magnetic field for carrying the toner is utilized effectively resulting in enhancement of image density and image quality.

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, for example, by supplying a conductive toner as a developer between a plurality of recording electrodes and a recording medium and applying a signal voltage to the recording electrodes to perform recording. The present invention relates to an apparatus such as a printer or a display apparatus that adheres this developer to a medium.

[0002]

2. Description of the Related Art Heretofore, in this type of apparatus, there is known an apparatus for forming an image by the method described in Japanese Patent Publication No. 51-46707.

FIG. 2 is an explanatory view showing the recording principle. By rotating the magnet roller 2 in the direction of the arrow, the conductive magnetic toner 1 as the developer is conveyed in the direction opposite to the magnet on the non-magnetic cylinder 3, and the recording signal is transmitted from the recording control circuit 13 to the recording electrode 4. By applying
The recording charge is injected into the conductive magnetic toner, and the toner adheres to the surface of the dielectric layer 6 due to the Coulomb force between the recording medium 5 and the grounded conductive layer 7 provided near the recording electrode. At this time, by conveying the recording medium in the direction of the arrow in the drawing, an image corresponding to ON / OFF of the recording signal can be formed on the recording medium and can be viewed through the opening 12a.

FIG. 3 is a cross-sectional view of a display device actually manufactured by using the above recording principle. In FIG. 3, FIG.
The members having the same numbers as in the above indicate the same members, and in addition, a mechanism for erasing the image once formed on the recording member by using the cleaning member 8, the conductive brush 8a and the cleaning magnet 9 is provided. Further, the toner scraped off after erasing is collected in the toner container 10 provided in the lower part and is devised so that it can be reused. Further, the recording medium is an endless belt-like sheet, and has a mechanism for conveying in the arrow direction using the recording roller 11, and these mechanisms are housed in the main body frame 12 and a wide display screen can be expressed with a thin depth. It is like this.

In the above apparatus, as a method of actually providing the recording electrode on the non-magnetic cylinder, as shown in FIG. 4, the flexible substrate 14 having the electrode row formed and the metal portion at the tip exposed is formed on the non-magnetic cylinder. There is a way to stick. At this time, a large number of toner holes 15 are provided in the flexible substrate so as not to hinder the toner transportation.

Further, as a method capable of forming an electrode array having a density higher than that of the flexible substrate in order to increase the recording density, a recording head made by patterning a metal thin film on a rigid substrate as shown in FIG. 16 are considered. In this recording head 16, the recording electrode supporting member is a rigid base 17 such as ceramics, and the recording electrodes are formed on this rigid base by the same method as in the semiconductor manufacturing process, so that the electrode pitch can be increased. After forming a metal thin film on a rigid base, apply a resist, form an electrode pattern through exposure and etching, and connect each electrode with the IC as a driving element using a connection method such as wire bonding. To create. In FIG. 5, the recording signal application IC 18 is mounted on a rigid base, and this IC
An IC drive circuit 19 for driving the circuit board 19 is created by mounting a mounting component 19b such as a connector, a resistor and a capacitor on a circuit board 19a, and a rigid board and a circuit board are connected on a support plate 20.

However, when the recording head is fixed on the non-magnetic cylinder, there is a problem that the smooth transportation of the toner is hindered by the mounting components on the IC drive circuit.

FIG. 6 is a cross-sectional view of a device in the vicinity of a recording area, which is a specific example of the vicinity of the recording electrode in which the above-mentioned problem occurs. In FIG. 6, the diameter of the non-magnetic cylinder 3 is 400 mm, the width of the recording head 16 is 20 mm, and the thickness is 2 mm excluding the mounting parts on the surface of the recording head 16. Further, the signal application IC 18
Also, the mounting component 19b is a sealing resin 2 that has both insulation and protection.
Covered with 1. Further, in order to fix the recording head 16 easily, a part of the surface of the non-magnetic cylinder 3 is processed so that a flat surface having a width of 14 mm is formed, and the end of the flat surface and the tip of the recording head are aligned with this flat surface portion. The recording head 16 is fixed. Since the thickness of the non-magnetic cylinder is limited, the width of the plane cannot be set to 14 mm or more in this example, and the rear end of the recording head 16 is fixed in a state of floating above the surface of the non-magnetic cylinder 3 and is not connected to the recording head 16. A gap is created between the magnetic cylinders 3. The presence of such a gap not only hinders the transport of the toner 1, but also causes the toner to enter the gap, and the toner is gradually accumulated and compressed, and acts to push up the recording head, thereby fixing the recording head 16. It also weakens and at the same time promotes toner deterioration. As a countermeasure, the recording head support 2
2 is provided so that the toner can be smoothly conveyed by using the slope of the base. However, even if such a measure is taken, since the rear end portion of the recording head 4 is located farthest from the magnet surface, the magnetic force for conveying the toner 1 is weakened, and there is no problem on the cylindrical surface 3. If even a few obstacles are present in this area, they will deposit toner 1 when overcoming the obstacles or passing between two or more obstacles, and these will serve as nuclei to form toner walls. , The toner cannot be transported.

Although such a problem can be solved by narrowing the width and thinning the recording head 16, it is not technically easy in practice, and even if it is realized, a large cost up is expected. Further, in consideration of commercialization, it is necessary to reduce the diameters of the magnet roller 2 and the non-magnetic cylinder 3 in order to reduce the size and weight, and a structure can be combined with a non-magnetic cylinder of a smaller diameter even with the same recording head width. Was wanted.

[0010]

The problem to be solved is that the toner is prevented from being conveyed by the mounting parts on the recording head provided on the non-magnetic cylinder.

[0011]

According to the present invention, mounting components necessary for a drive circuit board on a recording head are housed in a gap formed by the board and a non-magnetic cylinder which is a cylindrical member supporting a substrate. It is characterized by

As a result, the obstruction on the surface of the recording head is eliminated, so that the toner can be smoothly transported without forcibly reducing the width and the thickness of the recording head.

[0013]

【Example】

(Embodiment 1) The present invention will be described below with reference to illustrated embodiments.

FIG. 1 shows a first embodiment of an image recording apparatus according to the present invention. In the figure, the numbers given to the respective parts indicate the same members as the numbers in FIG.
In the present embodiment, the rear end of the support plate 20 is shortened by 4 mm, the mounting component 19b is mounted in this 4 mm area on the back surface of the circuit board 19a, and the back surface is mounted via the through hole 23 using the circuit board 19a as a two-layer board. The component 19b and the wiring on the surface are electrically connected, and the signal application IC 18 is connected on the surface of the substrate. The mounting component 19b mounted on the back surface is accommodated in the gap between the circuit board 19a and the non-magnetic cylinder 3, and is sealed by the recording head support 22 together with the gap.

By mounting the mounting parts on the back surface of the substrate in this manner, the transportability of the toner 1 on the surface of the substrate can be improved. It should be noted that power and signal voltage are supplied to the recording electrode and its electrical components of the above-described embodiment from the back side or the front side of the drawing. Specifically, the driving power supply voltage, the IC driving voltage, the clock signal, and the recording signal are supplied from one end side or both ends of the substrate by electric wires or printer wiring.

In the above embodiment, the recording medium 5 has a four-layer structure as shown in detail in the sectional view of the recording medium in FIG. 8, and the surface layer 6a has a volume resistance value of 10 ⁷ to 1 1.
In 0 ¹⁶ [Omega] cm, a butyral resin having a thickness of 1 to 20 [mu] m, acrylic resin, nylon resin, polyester resin, urethane resin, made plastic resin such as phenolic resin, the resistance layer 6b, the volume resistivity of 10 ⁰ -
It is 10 ⁷ Ωcm, has a thickness of 5 to 30 μm, and is composed of titanium oxide, aluminum oxide, tin oxide, or indium oxide dispersed in a plastic resin. The conductive layer 7 has a volume resistance value of 10 ⁰ to 1
The support layer 7a is made of a conductive vapor-deposited film such as aluminum having a thickness of 0 ² Ωcm and a thickness of 800 to 1000 A.
It is made of a plastic resin such as polyethylene terephthalate resin or polyimide resin having a thickness of 0 to 300 μm.

The conductive magnetic toner 1 is a particle having a particle size of about 10 μm, which is manufactured by internally adding magnetic powder to plastic resin and then externally adding carbon. The electric resistance value of the toner is a magnetic brush. The volume resistance value in the connecting direction of the toner is 10 ³ to 10 ⁸ Ωcm when it is formed into a chain shape by.

(Second Embodiment) FIG. 7 shows a second embodiment of the image recording apparatus according to the present invention. In the figure, the numbers given to the respective parts indicate the same members as the numbers in FIG.

In this embodiment, the signal application IC 18 is placed in the space formed on the front surface of the substrate by the back mounting of the mounting component 19b.
By mounting, the width of the entire recording head 16 can be reduced and the toner transportability can be further improved. Further, by keeping the rear end position of the recording head 16 as it is, and bringing the leading end position of the recording head closer to the center of the plane, the distance between the front end and the magnet 2 can be shortened and the magnetic force directly below the recording electrode can be strengthened. .. In the recording method used in the present invention, it is known that the stronger the magnetic force on the recording electrode 4, the higher the recording density and resolution.

By mounting the mounting components on the back surface in this manner, a margin is provided in the mounting space on the front surface, and the recording head 16 is provided.
It also has the effect of loosening the width constraint.

The recording medium 5 and the toner 1 used in this embodiment are the same as those used in the first embodiment.

(Third Embodiment) FIG. 8 shows a third embodiment of the image forming apparatus according to the present invention. In the figure, the numbers given to the respective parts indicate the same members as the numbers in FIG.

In this embodiment, the signal application IC 18 is mounted in the space formed on the substrate surface by mounting on the back surface of the mounting component 19b, and the recording electrode 4 is formed on the circuit board 19a to form the recording electrode. The width and thickness of the recording head 16 are reduced by eliminating the rigid support 20 of FIG. As a result, it becomes easier to strengthen the magnetic force directly below the electrodes as compared with the second embodiment, and the toner transportability is also improved.

The recording medium 5 and the toner 1 used in this embodiment are the same as those used in the first embodiment.

[0025]

As described above, in the image forming apparatus using the recording head of the present invention, the mounting parts necessary for the drive circuit board on the recording head are formed by this board and the cylindrical member supporting this board. It is mounted in the gap between the base and the non-magnetic cylinder so that the obstacles on the surface of the recording head can be reduced as much as possible without reducing the width or thickness of the recording head. A smooth toner transfer can be realized. It is also possible to reduce the width of the entire recording head by mounting the mounting components in this way to make room in the surface space of the substrate and mounting the signal application element there. As a result, it is possible to further improve the toner transportability and set the electrode tip to a position where the magnetic force is stronger to improve the recording density and resolution, or increase the distance between the recording electrode and the recording medium. It is advantageous in terms of mass productivity and cost.

[Brief description of drawings]

FIG. 1 is a sectional view around a developing area of an image forming apparatus using a first embodiment of the present invention.

FIG. 2 is an explanatory diagram of a recording principle of an apparatus used in the present invention.

FIG. 3 is a sectional view of the entire conventional image forming apparatus.

FIG. 4 is a perspective view of a recording electrode unit using a conventional flexible substrate.

FIG. 5 is a perspective view of a recording head.

FIG. 6 is a cross-sectional view around a developing area of an image forming apparatus using a conventional recording head.

FIG. 7 is a cross-sectional view around a developing area of an image forming apparatus using a second embodiment of the present invention.

FIG. 8 is a sectional view of the periphery of a developing area of an image forming apparatus using a third embodiment of the present invention.

FIG. 9 is a sectional view of the recording medium of the present invention.

[Explanation of symbols]

 1 Conductive Magnetic Toner 2 Rotating Magnet 3 Non-Magnetic Cylinder 4 Recording Electrode 5 Recording Medium 7 Conductive Layer 7a Support Layer 12 Body Frame 16 Recording Head 17 Electrode Forming Rigid Base 18 Signal Applying IC 19 IC Drive Circuit 19a Circuit Board 19b Mounting Parts 20 Support plate 22 Base support 23 Through hole

Claims (1)

Claim: What is claimed is: 1. A plurality of recording electrodes, a drive circuit for applying a recording signal to the recording electrodes, a means for supplying a developer onto the recording electrodes, a dielectric layer and a conductive layer. A recording medium,
In an image forming apparatus having means for relatively moving the recording electrode and the recording medium, the recording electrode, a recording signal applying element, and a drive circuit for driving the element are formed on a rigid substrate. An image forming apparatus, wherein a recording head is fixed on a non-magnetic cylindrical member, and a drive circuit mounting component is mounted in a gap formed by the rigid substrate and the cylindrical member.