JPH03260666A - Image forming device - Google Patents

Abstract

PURPOSE:To make a device function at low impressed voltage and to apply it to color recording by providing many-divided recording electrodes near a position where a developer carrier and a back electrode are opposed to each other, causing alternating electric field to act to the recording electrode in accordance with a recording signal and making developer fly so that it may be transferred and stuck to a recording medium. CONSTITUTION:When the developer carrier 1 and the back electrode 5 are driven, the developer is charged by a regulating charging member 2 and applied to the surface of the carrier 1 as a thin layer 4. When the thin layer 4 comes to the position of the recording electrode 3, it is powdered to be cloud by the electric field generated by electrode plates 301-306 corresponding to switching elements 701-706 which are turned on in response to the recording signal, and it scatters and flies in a developing area R. Then, it is transferred and stuck to the recording medium 9 by the action of the electric field by a bias power source 8 and the desired pattern is visualized. Thus, a clear image is formed at the low action voltage and the device is applied to the color recording.

Description

[Detailed description of the invention] Product 1! The present invention relates to an image forming apparatus such as an information recording apparatus and an information display apparatus that electrostatically records and displays information.

[Kanji-Nira I] This type of image forming device has two types of image forming devices: an electrostatic image forming type that forms an electrostatic latent image on a recording medium and visualizes this latent image using a developer; A toner direct drive type is known in which a visible image (toner image) is directly formed on a recording medium by applying a corresponding electric field.

A toner direct drive type image forming apparatus uses conductive toner, applies a voltage to a needle-shaped recording electrode, inductively charges the conductive toner near the recording medium, and uses the electric force to attach the conductive toner to the recording medium. There is a system in which the recording electrode is placed on the toner side, for example, US Pat. No. 391,477.
For example, there is the device described in No. 1, and US Pat. No. 4,396,927 in which recording electrodes are arranged on the recording medium side.

Also, U.S. Pat.
No. 6570 uses a control member as a recording electrode that controls the passage and blocking of charged toner, and applies an electric field according to a recording signal to the control member to control the passing and blocking of the charged toner, thereby causing the charged toner to pass and be blocked onto the recording medium. An image forming apparatus that forms a visible image is disclosed.

However, the device described in U.S. Pat. Since the toner comes into contact with the toner, there are problems in terms of maintainability and reliability. Further, in the device described in U.S. Pat. No. 4,396,927, since the recording electrodes are arranged on the recording medium side, the applied voltage must be set high, and the recording medium must also be in the form of a belt. However, there is a problem in that the degree of freedom in configuration is reduced. Furthermore, since both of these devices use conductive toner, electrostatic transfer is difficult, and it is believed that there are difficulties in producing color images.

Further, in the apparatus described in US Pat. No. 3,689,935, toner is not supplied uniformly, and images on the 8-color medium tend to be uneven, making high-speed recording difficult. Further, the toner causes clogging of the control member, making it difficult to put it into practical use. On the other hand, the apparatus described in Japanese Patent Application Laid-Open No. 58-96570 also has an inherent problem of a complicated structure.

As described above, these conventional image forming apparatuses are structurally complex, require high applied voltages, and use conductive toner, making it difficult to perform electrostatic transfer efficiently.
It can be seen that there are various problems such as difficulty in applying it to color recording.

Therefore, an object of the present invention is to provide an image forming apparatus which has a relatively simple structure, functions satisfactorily with a relatively low applied voltage, is highly reliable, and can be sufficiently applied to color recording. It is.

This object can be fully achieved by the configuration of the invention described below. In summary, the present invention includes a developer carrier on which a thin layer of charged developer is formed, and a back electrode that is disposed opposite to the developer carrier and moves and guides a recording medium along the outer peripheral surface of the developer carrier. and a record divided into a large number of parts, which are arranged near a position where the developer carrier and the back electrode face each other, and whose ends are arranged close to or in contact with the developer layer on the developer carrier. applying an electric field to the electrode and any recording electrode of the recording electrode according to the recording signal;
an alternating electric field applying means for causing the developer to fly;
The image forming apparatus is characterized in that it has an electric field applying means for transferring and adhering the flying developer to the recording medium.

EXAMPLE E Hereinafter, an image forming apparatus according to the present invention will be specifically explained with reference to the drawings.

In FIG. 1, a drum-shaped developer carrier 1 is rotatably provided, and is disposed in a development region R to face a roll-shaped back electrode 5. As shown in FIG. The developer carrier 1 is arranged in five developer containers (not shown), and the surface of the developer carrier 1 is supplied with the developer in the developer container.

The developer carrier 1 is rotationally driven in the direction of the arrow A, and as it rotates, it carries the developer on its surface and transports it in the direction of the arrow. The developer on the developer carrier 1 is regulated to a predetermined thin layer thickness and is charged to a desired polarity.

Also, with the tip facing the development area R,
The recording electrode 3 is located on the upstream side of the developer layer 4 of the developer carrier l.
placed in close proximity to or in contact with. The recording electrode 3 is connected to an alternating electric field applying means, that is, an AC power supply 6 via a switch 7, for applying a voltage between the recording electrode 3 and the developer carrier l according to the recording signal. There is. The switch 7 is turned on and off in response to a recording signal.

On the other hand, a recording medium 9 is supplied to the circumferential surface of the back electrode 5 and is configured to move together with the back electrode 5 in the direction of arrow B.

Further, a means for applying a developing bias electric field, that is, a DC bias power supply 8 is disposed between the back electrode 5 and the developer carrier l.

In addition, in this embodiment, the regulating charging member 2 is
4-43038, JP 60-83648, JP 60-73649, JP 61-138
Using a blade such as a metal blade or a rubber blade as seen in Japanese Patent Application Laid-open No. 967 and Japanese Patent Application Laid-open No. 62-24282, the blade is pressed against the developer carrier 1, and the developer carrier, developer, and blade are pressed against the developer carrier 1. It is constructed by taking into account the effects of mutual frictional force and frictional charging, thereby forming a thin layer of developer with a predetermined thickness on the developer carrier 1, and at the same time reducing the charge of the developer. It is something to do.

The developer carrier 1 is selected in relation to the developer and the regulating charging member 2 as described above, but generally /M2. A material made of metal such as SUS or semiconductive plastic and whose surface is textured with a size of about 0.1 to several tens of microns is preferably used.

Further, the recording electrode 3 is formed by, for example, as shown in FIG. 2, a large number of electrode plates 301 to 306 divided in the radial direction of the developer carrier 1 are closely attached to an insulating substrate 300. It consists of At this time, the substrate 300 and the electrode plates 301 to 306
. . are preferably aligned on the same plane, and these tips are arranged close to or in contact with the developer layer 4 on the developer carrier 1. Alternatively, the recording electrode 3 may be constructed by arranging wire-shaped conducting wires whose outer peripheries are covered with an insulating material in parallel in a row.

Further, the control switch 7 connected to the recording electrode 3 is composed of on/off switch elements 701 to 706 corresponding to each electrode plate 301 to 306, and the control switch 7 is composed of on/off switch elements 701 to 706 corresponding to the respective electrode plates 301 to 306, and is arranged at a position corresponding to the recording signal. The switch element is configured to be activated for a time corresponding to the recording signal.

With this configuration, the developer carrier 1 and the back electrode 5 are both driven in the directions of arrows A and B, and the recording medium 9 is also moved and guided in the same direction in close contact with the circumferential surface of the back electrode 5. Developer is supplied to the outer peripheral surface of the developer carrier 1 and is carried as the developer carrier 1 moves. The developer is supplied to the regulated charging member 2
The developer is charged to a desired polarity and simultaneously regulated to a desired thickness, and is applied as a thin layer 4 to the surface of the developer carrier 1. If desired, it is also possible to swing the developer carrier 1 and the recording electrode 3 beyond the electrode plate pitch of the recording electrode in order to further equalize the developer layer 4.

When the developer thin layer 4 reaches the position of the recording electrode 3, it is turned into a powder cloud by the action of an electric field generated at the electrode plate corresponding to the switch element turned on in response to the recording signal, and the developing agent thin layer 4 is turned into a powder cloud. , it is diffused and launched from its tip. The flying and diffused developer transfers and adheres to the recording medium 9 due to the electric field action of the bias power supply 8, and a desired image pattern corresponding to the recording signal is visualized.

The image on the recording medium 9 is fixed as necessary, but the image may be transferred to another medium and fixed on this different medium before fixing.

FIG. 3 shows another embodiment of the image forming apparatus according to the present invention. This embodiment shows a configuration for color development.

In this embodiment, the back electrode 501 is driven in the direction of arrow C, and in accordance with this, the recording medium 901 is driven in the same direction while closely contacting the back electrode 501 via the deflection roller 14. Around the back electrode, a developer carrier 101.
102 and 103 are prepared, and developers of different colors are supplied to each.

Further, similarly to the embodiment described in connection with FIG. A visible image corresponding to the recording signal is sequentially formed on the recording medium 901 that moves along the surface of the back electrode 501 with the help of the roller 14 . As a result, multicolor development (
color development) is realized. This multicolor image is produced by the fixing device 1.
0 on the recording medium 901.

FIG. 4 shows another embodiment of the image forming apparatus according to the present invention. In this embodiment, the recording medium 911 is the back electrode 5.
02 and a drive roller, and is driven by a drive roller 13 in the direction of the arrow. Further, the developer carrier 104 disposed facing the back electrode 502 is located inside the toner container 12, and the developer 401 is applied in a thin layer by the regulating charging member 201. Further, the same recording electrode 314 as described above is connected to the developer carrier 1.
04, and turns the developer into a powder cloud by the action of an electric field according to the recording signal, with the help of a developing bias electric field applied between the back electrode 502 and the developer carrier 104. A visible image is formed on the recording medium 911, and is used for recording and display in this embodiment.

After the recording and displaying function is completed, the visible image on the recording medium 911 is erased by the cleaning device 11, and is prepared for the next recording and displaying. Furthermore, by controlling the cleaning device 11, it is also possible to record and display other information superimposed on the previous recorded display. Furthermore, if desired, the visual image on the recording medium 911 may be transferred to another recording medium.

FIG. 5 shows a modification in which the embodiment shown in FIG. 4 is applied to multicolor development. Here, around the back electrode 502, developer carriers 105, 106, and 107 equipped with developers of different colors are arranged in separate development areas, and visible images are formed in response to each recording signal. This enables multicolor recording and display. Although recording electrodes and the like are not shown in FIG. 5, they are constructed in the same manner as the other embodiments.

Next, a more specific example of the image forming apparatus having the above configuration is as follows.

Example 1 In an image forming apparatus having the configuration shown in FIGS. 1 and 2,
The developer used was a developer containing a polyester resin, a charge control agent, a coloring pigment, etc. and having an average particle size of about 12 microns.

A 5 usH roller with a diameter of 20 mm is used as the developer carrier 1, and its circumferential surface is sandblasted to obtain a JISIO point average roughness rating (JIS-1).
B O610) A roughening process of 1 to 2 um was performed.

The regulating charging member 2 is made of urethane rubber with a thickness of 2 mm and a hardness of 40°, and the recording electrode 3 is made of urethane rubber with a thickness of 12.5 μm.
Three phosphor bronze electrode pieces with a thickness of 20 μm are placed on PET of
Those arranged at a pitch of 0.00 μm were used.

The developer carrier 1 is rotated at a circumferential speed of 100 mm/sec, and the regulating charging member 2 is pressed against the developer carrier 1 with a pressure of about 100 g/cm.
A thin layer of charged developer was formed on top. The thickness of the developer layer was about 2 to 3 layers of developer.

The recording electrode 3 is powered by a power source 6 in response to the recording signal.
A sine wave of 5 KHz and 500 Vp-p was applied, and a DC voltage of approximately 100 V was applied as a bias power source between the developer carrier 1 and the back electrode 5. by this,
A visible image corresponding to the recorded signal could be obtained on the recording medium. At this time, the recording medium 9 is 80 g/rr?
Plain paper was used, and the position of the back electrode 5 was set so that the distance between the recording medium 9 and the developer carrier 1 was approximately 300 μm in the development area.

Example 2 In the imaging device according to the embodiment in Fig. 3, each recording electrode 311.312.313 is compatible with the red, blue, and black, black, black, black, black, black, black, each of the developers 101.102.
103, and each was operated under the same conditions as in Example 1. As a result, a three-color recorded image was obtained.

Example 3 In the image forming apparatus according to the example shown in FIG. 4, an endless belt made of white PET was used as the recording medium 911, and the image forming apparatus was operated under the same conditions as in Example 1.

As a result, a clear display pattern could be obtained.

Note that the cleaning device 11 has a thickness of 2 mm,
Urethane rubber with a hardness of 40 degrees is used, and the recording medium 91 is pressed against the recording medium 911 by pressing the rubber blade against the recording medium 911.
1 cleaning was performed. The cleaned developer was collected into a toner container and used again.

Example 4 In the image forming apparatus according to the example of FIG. 5, each of the developer carriers 105, 106, and 107 carries developers of red, blue, and black tones under the same conditions as in Example 3. I recorded it with . This made it possible to obtain a three-color display pattern.

Each of the above embodiments can be modified in various ways, and suitable conditions are set depending on the materials and configuration used.For example, as a power source for applying an electric field to the developer carrier and recording electrode, i
oo to 1000 Vp-p, 1 = 10 KHz, a triangular wave, a rectangular wave, a pulsating wave, a pulse train wave, and other distorted waves are set, and it is also possible to use these by superimposing a DC component.

The image forming apparatus according to the present invention configured as described above is as follows:
The recording electrode turns the developer into a powder cloud at the location corresponding to the recording signal, and the DC bias electric field transfers and adheres the developer to the recording medium, so it operates at a relatively low operating voltage and can form sufficiently sharp images. Moreover, it has the features of being simple in structure and high in reliability as a whole. Furthermore, the present invention allows for a wide selection of recording media in order to perform developer control recording outside the recording medium (and furthermore, by using a non-magnetic and insulating developer, it is possible to perform multi-color recording, etc.). It has the advantage of being able to be fully expanded.

[Brief explanation of drawings]

FIG. 1 is a schematic configuration diagram showing an embodiment of an image forming apparatus according to the present invention. FIG. 2 is a partial perspective view of one embodiment of the recording electrode. 3 to 5 are schematic configuration diagrams of other embodiments of the image forming apparatus according to the present invention. l: developer carrier 2: regulating charging member 3: recording electrode 4: developer thin layer 5: back electrode 6: AC power supply 8: DC bias power supply 9: recording medium

Claims (1)

[Claims] 1) A developer carrier on which a thin layer of charged developer is formed, a back electrode that is disposed opposite to the developer carrier and moves and guides a recording medium along its outer peripheral surface, and the developer. A recording electrode divided into a large number of parts, which is disposed near a position where the carrier and the back electrode face each other, and whose end portion is disposed close to or in contact with the developer layer on the developer carrier, and a recording signal. an alternating electric field applying means for applying an electric field to any recording electrode of the recording electrodes in accordance with the above, and causing the developer to fly; and an electric field applying means for causing the jetted developer to transfer and adhere to the recording medium. An image forming apparatus comprising: