JPH0535429B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method and apparatus for forming an image by electronic plane scanning, and more particularly to an image forming method and apparatus capable of forming an image on plain paper using toner.

(Prior art and its problems) Electrophotographic technology, which is widely used in office copying machines and the like, is applied to printing devices such as laser printers to achieve high-speed, high-quality recording at low noise levels. However, the image forming process using electrophotography is complicated, consisting of electrostatic latent image formation, toner phenomenon, toner image transfer, fixing, and cleaning of the photosensitive drum surface, which results in the complexity of the device mechanism, which This was the main cause of a decline in maintainability and reliability or an increase in equipment manufacturing costs.

In addition to electrophotographic techniques, various high-speed electronic recording techniques are known. Electrostatic recording technology, in which a needle electrode is brought into contact with the surface of a conductive recording medium and a signal voltage is applied to form an electrostatic charge pattern on the surface of the recording medium, which is then visualized by toner development, is capable of high-speed, high-quality recording. This is one of the most powerful technologies available. This electrostatic recording technology has the feature that the image forming process is simpler than that of electrophotographic technology, so it is easy to miniaturize the device. The necessity of high voltage is considered to be a factor that significantly impairs the versatility and practicality of the device.

As another example of conventional recording technology in which the image forming process is simplified, a recording apparatus disclosed in USP-3816840 is known. As shown in the cross-sectional view in FIG. Recording electrodes 3 made of magnetic material arranged in a line along the direction, and a character generator 4 connected to the recording electrodes 3.
The rotary magnet 5 provided inside the toner transport member 1, the toner container 7 which contains the conductive magnetic toner 6 and in which the toner transport member 1 is provided, and the back electrode 8 are in close contact with each other. and an insulating recording medium 9 disposed close to the recording electrode 3.

When the rotating magnet 5 rotates in the direction of the arrow A, the conductive magnetic toner 6 moves along the surface of the toner conveying member 1 in the direction of the arrow B, forming a spike of toner 6 at the tip of the recording electrode 3. When a signal voltage is applied to the recording electrode 3, the surface of the recording medium 9 is charged through the ears of conductive toner 6, and at the same time, the toner at the tips of the ears adheres to the surface of the recording medium 9. In this way, a toner image is formed on the surface of the recording medium 9. However, the conventional recording apparatus shown in FIG. 4 has a problem in that the resolution of the formed toner image is significantly lower than the arrangement density of the recording electrodes 3. The reason for this is that the spikes of toner 6 formed at the tips of the recording electrodes 3 are not separated corresponding to each recording electrode, and the contact area between the spikes of toner 6 and the recording medium 9 is small per electrode. One example is that it is extremely large compared to the area of the dots recorded. Therefore, when a signal voltage is applied to the recording electrode 3, the charged area on the surface of the recording medium 9 formed through the ears of the conductive toner 6 expands widely centering on the portion facing the recording electrode, resulting in deterioration of resolution. It happens.

Further, the conventional apparatus described above requires an insulating recording medium known as electrostatic recording paper, for example. The need for such so-called special paper increases running costs, which is a major drawback from a practical standpoint.

As mentioned above, although conventional electrophotographic technology and electronic recording technology enable high-speed, high-quality recording, it is also possible to create equipment that is smaller, lower cost, and has excellent maintenance reliability. A new recording technology that could use paper was required.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to solve the above-mentioned problems in the prior art, and to provide an image forming method that can form a high-resolution image on plain paper, and an image forming method that can form a high-resolution image on plain paper and that provides maintainability and reliability. An object of the present invention is to provide an image forming apparatus that has excellent properties and can be easily reduced in price and size.

(Means for Solving the Problems) In order to solve the above-mentioned problems, the image forming method provided by the first invention of the present application applies toner to a large number of recording electrodes that are arranged on a plane so as to be insulated from each other. Electrostatically adhering the toner, further superimposing a signal voltage on each of the recording electrodes to control the electrostatic force that causes the toner to adhere to each of the recording electrodes, and applying unbalanced vibration to the recording electrode to adjust the toner according to the electrostatic force. The toner is moved toward the recording medium to the end of the recording electrode, and an electrostatic force is applied to the toner in a direction to cause the toner to adhere to the surface of the recording medium disposed close to the end of each of the recording electrodes. The toner attached to the end of each recording electrode is selectively attached to the surface of the recording medium in accordance with the signal voltage to form a toner image on the recording medium.

In order to solve the above-mentioned problems, the image forming apparatus provided by the second invention of the present application includes an electrode substrate having a large number of recording electrodes arranged insulated from each other;
a toner replenishing means for replenishing toner on the surface of the recording electrode; a counter electrode disposed opposite to each of the recording electrodes; and a voltage applied between each of the recording electrodes and the counter electrode to supply the toner to the recording surface. voltage applying means for electrostatically adhering the toner to the electrode; signal voltage applying means for applying a signal voltage to each of the recording electrodes to control the electrostatic force that causes the toner to adhere; vibrating means for moving the toner along the recording electrodes to the tips of the electrode substrates according to electric power; and applying an electrostatic force to the toners that have moved along the respective recording electrodes to the tips of the electrode substrates. It is characterized by comprising an electrostatic accelerating means for selectively adhering the toner to a recording medium disposed close to the tip of the electrode substrate and disposed on the back surface of the recording medium.

(Function) In the conventional technology, in order to prevent density unevenness, a much larger amount of toner is supplied than the actual amount consumed, and this large amount of toner is used to record on the recording medium. The resolution of images such as characters and figures has decreased significantly. In contrast, in the present invention, toner transport is precisely controlled using electrostatic force and unbalanced vibration, and the toner is replenished according to the consumed amount, and the toner to be replenished is distributed in advance in the vicinity of the recording medium in a thin and uniform layer. Arrange it to.
By replenishing toner in this manner, the present invention enables high-quality recording with little resolution deterioration. Furthermore, the present invention makes it possible to use plain paper by using electrostatic force to selectively extract toner from the uniform toner layer and adhere it to the surface of the recording medium.

(Example) Examples of the present invention will be given below, and the present invention will be described in detail with reference to the drawings of the examples.

FIG. 1 is a diagram showing the configuration of an embodiment of an image forming apparatus according to the second invention of the present application. This embodiment is also an example of an apparatus implementing the first invention of the present application. In this embodiment, an electrode substrate 102 has a large number of recording electrodes 101 arranged insulated from each other.
Then, the stored toner 103 is transferred to the recording electrode 101 at any time.
A toner supply tank 104 for replenishing the surface of the toner, a counter electrode 105 arranged oppositely above the recording electrode 101, and a voltage applied between the selected recording electrode 101 and the counter electrode 105, A voltage source 106 applies an electrostatic force to the toner on the recording electrode 101, and each recording electrode 101 is selectively connected to the voltage source 106 or grounded according to an image signal. The electrode substrate 102 includes a switch means 107 for controlling the electrostatic force that causes toner to adhere to the electrode substrate 102; The toner on the electrode substrate 102 is transferred to the recording electrode 101 by applying an unbalanced vibration to the recording electrode 101.
vibrating means 112 for moving the electrode substrate 102 along the direction to the tip 111 of the electrode substrate 102;
a roller electrode 114 disposed on the back surface of the recording medium 113 in order to apply electrostatic force to the toner that has moved to the tip 111 of the recording medium 113 and selectively adhere the toner to the recording medium 113; and a power source that applies an accelerating voltage to the electrode 114. 115.

For the electrode substrate 102, an insulating material such as glass, ceramic, or organic resin can be used. A printed circuit board made of a composite material of glass fiber and epoxy resin is also very suitable as an electrode substrate in the present invention. Although a conductive magnetic toner may be used as the toner, a positively or negatively charged insulating toner is more preferable. By using a charged toner, the toner can be transferred to the recording electrode 10.
It becomes possible to electrostatically control the adhesion to 1 more reliably.

After the toner spills onto the recording electrodes 101 from the toner supply tank 104, it is conveyed along each recording electrode 101 toward the tip 111 of the substrate. The toner is conveyed by applying unbalanced vibration to the substrate 102. That is, the substrate 102 is displaced back and forth in the direction along the recording electrode 101, and the displacement with respect to time is as shown in FIG. 2 as an example. Displace it suddenly. Such unbalanced vibrations are caused by the power source 10 that excites the piezoelectric element 109.
This is realized by making the excitation voltage waveform from 8 into a sawtooth waveform. Although the piezoelectric element 109 is not shown, since it is fixed to a strong support, the generated vibrations are mainly transmitted in the direction of the transmitter 110. The transmitter 110 and the substrate 102 are fixed to each other, and the sawtooth vibration amplified by the transmitter 110 causes the substrate 102 to also perform sawtooth vibration. In FIG. 2, the substrate 102 is the recording medium 11
3, that is, when the displacement is performed slowly, the toner particles on the recording electrode 101 on the surface of the substrate 102 move together with the substrate 102;
If the substrate 102 is suddenly displaced in a direction away from the recording medium 113, the toner particles will move away from the substrate 102.
The substrate 1 cannot follow the displacement of the substrate 102 and moves in the opposite direction to the displacement of the substrate 102, that is, toward the tip 111 of the substrate 102.
Slide on the surface of 02. In this way,
The toner supplied onto the substrate 102 from the tank 104 is always subjected to a force that causes it to be sent to its tip 111, and moves on the substrate 102 in the form of a layer of uniform thickness. In order to selectively extract toner from the substrate tip 111 and form a toner pattern on the surface of the recording medium 113, the application of voltage to the recording electrode 101 is selectively controlled according to the image signal.

The method of toner selection will be explained in detail with reference to the sectional views of the electrode substrate shown in FIGS. 3a and 3b.
Although this figure shows an example in which positively charged toner 120 is used, exactly the same effect can be obtained when negatively charged toner is used by reversing all the polarities. As shown in these figures, the charged toner forms a thin, uniform layer on the recording electrode 101 on the surface of the substrate 102. Although the figure shows a state in which the toner 120 is deposited in only one layer, the same concept may be applied even if the toner 120 is deposited in many layers.

First, as shown in FIG. 3a, the recording electrode 101
is grounded by the switch means 107, the voltage V from the voltage source 106 is applied between the counter electrode 105 and the recording electrode 101, so that the charged toner 120 on the recording electrode 101 is electrostatically It is strongly attracted to the recording electrode 101. For this reason,
The toner particles and the recording electrode 1 that were sliding toward the tip 111 due to the unbalanced vibration of the substrate 102
01 increases, and the sliding movement of the toner 120 is stopped.

Toner 120 is transferred from the substrate tip 111 to the recording medium 1
13, the recording electrode 101 is electrically connected to the voltage source 106 using a switch means 107, as shown in FIG. or
Or reduce the potential difference. As a result, the electrostatic force that attracts the toner particles to the recording electrode 101 becomes smaller, the frictional force between the toner particles and the recording electrode 101 becomes smaller, and the toner 120 is transferred to the substrate again.
You will be able to slide on 02. Board tip 11
The toner 120 in the vicinity of the recording electrode 101 and the roller electrode 114 will slip out of the tip due to the sliding movement.
15 applies a voltage of 2V, and due to this large potential difference, the toner protruding from the tip 111 is attracted to the surface of the recording medium 113 by a strong electrostatic force and adheres to the surface.
If Vth is the minimum voltage required to make the toner 120 near the tip 111 adhere to the recording medium 113, then 2V>Vth>V in order to perform the above recording operation. It is necessary to set the voltage V.

As described above, in this example, the recording electrode 1
By controlling the voltage applied to 01, only the toner on the selected recording electrode 101 can be attached to the surface of the recording medium 113, thereby recording images such as characters and figures. It is possible. Since the toner 120 adhering to the surface of the recording medium 113 is collected in advance on the fine recording electrode 101, it is possible to obtain high-resolution recording in this embodiment. Furthermore, since this embodiment has a simple configuration, it has excellent maintainability and reliability.
It is easy to reduce the price and size.

(Effects of the Invention) The present invention realizes uniform and precise conveyance control of toner particles by using mechanical vibration and electrostatic force, and as a result provides a new recording method and device with a simple principle and configuration. . According to the invention,
As mentioned above, there is an image forming method that can form high-resolution images on plain paper, and a high-resolution image forming method that is small, low cost, has excellent maintenance reliability, and can use plain paper, which is difficult to achieve with conventional electrophotographic technology or electronic recording technology. An image forming device with high resolution can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram of an image forming apparatus which is an embodiment of the second invention of the present application, and FIG. 2 is a diagram for explaining the temporal displacement of the toner conveying substrate in the image forming method and apparatus according to the present invention. , Figure 3 a, b
4 is a schematic cross-sectional view for explaining toner control in the image forming method and apparatus according to the present invention, and FIG. 4 is a schematic cross-sectional view showing a conventional image forming apparatus. 101... Recording electrode, 102... Electrode substrate, 1
03...Toner, 104...Toner supply tank,
105... Counter electrode, 106... Voltage source, 107
... Switch means, 108 ... Power supply, 109 ...
Piezoelectric element, 110...transmitter, 111...substrate tip, 112...vibration means, 113...recording medium,
114... Roller electrode, 115... Power supply, 12
0... Positively charged toner, 1... Toner conveying member, 2
... Insulator, 3 ... Recording electrode, 4 ... Character generator, 5 ... Rotating magnet, 6 ... Conductive magnetic toner,
7... Toner container, 8... Back electrode, 9... Recording medium.

Claims (1)

[Scope of Claims] 1. Toner is electrostatically attached to a large number of recording electrodes arranged insulated from each other on a plane, and a signal voltage is superimposed on each of the recording electrodes so that the toner is applied to each of the recording electrodes. controlling the electrostatic force that causes the toner to adhere to the recording electrode, applying unbalanced vibration to the recording electrode, and moving the toner toward the recording medium to the end of the recording electrode according to the electrostatic force, and approaching the end of each of the recording electrodes. An electrostatic force is applied to the toner in a direction to cause the toner to adhere to the surface of the recording medium arranged in a manner such that the toner adhered to the end of each of the recording electrodes is selectively applied to the surface of the recording medium in accordance with the signal voltage. An image forming method comprising the step of forming a toner image on the recording medium by adhering the toner to the recording medium. 2. An electrode substrate having a large number of recording electrodes arranged insulated from each other, toner replenishing means for replenishing toner on the surface of the recording electrodes, a counter electrode arranged opposite to each of the recording electrodes, and each of the above-mentioned recording electrodes. Voltage application means that applies a voltage between the recording electrode and the counter electrode to electrostatically adhere the toner to the recording electrode, and controls electrostatic force that applies a signal voltage to each of the recording electrodes to cause the toner to adhere. a signal voltage applying means for applying unbalanced vibration to the electrode substrate, and an excitation means for applying unbalanced vibration to the electrode substrate and moving the toner along the recording electrode to the tip of the electrode substrate according to the electrostatic force;
Electrostatic force is applied to the toner that has moved along each of the recording electrodes to the tip of the electrode substrate, and the toner is selectively attached to a recording medium disposed close to the tip of the electrode substrate, and the toner is placed on the back side of the recording medium. An image forming apparatus comprising an electrostatic accelerating means.