JPS63216073A - Image forming device - Google Patents

Abstract

PURPOSE:To prevent a toner from scattering, by providing an erasing member on the upper part at a specific interval from a developer supply means, and setting the length of a magnet in the erasing member shorter than the length of a magnet roller in the developer supply means. CONSTITUTION:As for a developer supply means, a rotatable magnet roller 2 is provided in a fixed non-magnetic cylindrical type member 3, and also, an erasing member is constituted of a cleaning member 8 and a magnet 9. Its erasing member is installed at the upper part at an interval of 10-150mm from the developer supply means, and against the display width direction, the length of the magnet 9 in the cleaning member 8 is set at least >=5mm shorter than the length of the magnet roller 2 in the developer supply means. In such a way, a toner which has dropped down from the cleaning member drops within a range where magnetic force of the magnet roller 2 on the non-magnetic cylinder 3 work, therefore, scattering of the toner caused by its drop is prevented.

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention relates to image forming apparatuses, particularly printers and printers that apply a voltage between a recording electrode and a recording medium to deposit image forming particles (toner) on the recording medium. The present invention relates to an image forming device such as a display device.

(Prior art) As such an image forming method,
There is a method known from Publication No. 707, etc. In this method, as shown in FIG. 3, conductive magnetic toner 1 is conveyed over a non-magnetic cylinder 3 by a rotating magnet 2 and passed over a recording electrode 4 made of a magnetic material. Then, a voltage is applied between the recording electrode and the conductive layer 7 of the recording medium 5 having the insulating layer 6 on the surface thereof, and toner is adhered to the recording medium to form an image.

Further, as a further development of the above, a display device has been devised using the recording electrode. 2A and 2B show the overall configuration. In the figure, 1 is toner, 4 is a recording electrode, 5 is a recording medium, 8 is a cleaning member, 9 is a magnet,
10 is a toner container, 11 is a recording medium indicating member, and 12 is a main body frame.

An image is formed on the recording medium 5 by toner being attached or not attached depending on the signal voltage from the recording electrode 4.

For example, when the signal voltage from the recording control section 13 is +60V, the toner adheres to the recording medium 5, and when the signal voltage is Ov, it does not adhere, forming an image. After an image is formed by toner and displayed on the recording medium while being conveyed in the direction of the arrow, it is rubbed and erased by the toner l on the cleaning member 8 and prepared for the next recording again.

To describe the toner circulation path from recording to erasing to preparation for the next recording in the conventional example, toner on the recording electrode is injected with charge based on a signal from the electrode, and adheres to the recording medium.

After being displayed, the toner is carried to a cleaning member as the recording medium is transported, and the toner is magnetically attracted by a magnet in the cleaning member and is erased by rubbing with the toner accumulated on the cleaning member. When more than a certain amount of toner accumulates on the cleaning member, the action of gravity becomes stronger than the magnetic force in the cleaning member, and the toner falls freely from the cleaning member to the non-magnetic cylindrical part, the recording electrode part, or the toner container. The paper is transported by the machine and prepared for the next recording.

The toner is conveyed by the rotation of the rotating magnet 2, and the direction in which the toner is conveyed is in the opposite direction to the rotation of the magnet. The toner at the end that falls from the cleaning member 8 onto the non-magnetic cylindrical member 3 due to gravity is removed by the rotating magnet 2 in the non-magnetic cylindrical member 3.
If the toner falls within the range where the magnetic force acts (area A in the figure), it will be transported onto the recording electrode 4 again, but if the toner falls into the area where the magnetic force does not act (area B in the figure). is not used for recording again, and has drawbacks such as toner scattering and staining the device itself, wasteful consumption of toner, and the need to replenish toner from outside.

Furthermore, in order to solve the above-mentioned drawback, if the length of the magnet 9 in the cleaning member is made shorter than the rotating magnet 2 in the developer conveying means, the ends of the recording medium 5 and the magnet 9 can be Vibration also causes defects in cleaning and toner adhesion.

Another drawback is that when the developer is transported by the rotation of the rotating magnet 2, the developer is not only transported in the circumferential direction but also floats and scatters in the lateral direction at both ends of the non-magnetic cylinder top 3. there were.

(Purpose) The present invention has been made in view of the above-mentioned drawbacks, and it is an object of the present invention to prevent toner from scattering, suppress device dirt, and smoothly circulate toner so that recording, displaying, and erasing can be repeated, and recording can be performed again. The purpose of the present invention is to prevent toner from deviating from the circulation path and scattering.

(Structure for Achieving the Object) The present invention has a recording electrode having a large number of recording elements, a means for supplying developer to the recording electrode, a drive circuit for applying a signal voltage to the recording electrode, and a drive circuit that has a plurality of recording elements in the vicinity of the recording electrode. The image forming apparatus includes a recording member that moves relatively to the image forming apparatus, and an erasing member provided for erasing the recorded image, wherein the developer side supply means is located within a fixed non-magnetic cylindrical member. A rotatable magnetic field generating means is provided, and the erasing member is constituted by a non-magnetic member and the magnetic field generating means, and the erasing member is installed above the developer supplying means at an interval of 10 to 150+ m, The length of the magnet in the erasing member in the display width direction is at least 5 mm shorter than the length of the magnet roller in the developer supply means.

(Embodiment) Figures 1A to 1C show the overall configuration of an embodiment of the present invention. FIG. 1D is a positional relationship diagram according to the present invention. In the figure,
Explanation numbers that are the same as those in the conventional example are omitted. Figure 1A is a sectional view of the device, Figure 1B is a view from the opposite direction to the display surface (back side), and Figure 1C is an enlarged view of the peripheral end of the developer conveying member. The symbol 13 indicates the electrode, the developer base stop member 13, the space between the non-magnetic cylinder and the cleaning member, and the intersection '' the range in which toner falls from the cleaning member.

The numbers are the same as those described in the conventional example, so they are omitted.

As shown in the figure, toner l is conveyed on a non-magnetic cylinder 3 to an electrode 4 by the rotation of a rotating magnet 2 serving as a magnetic field generating means, and the toner is deposited on a recording medium 5 based on a recording signal and displayed. Thereafter, the toner is carried to the cleaning member 8 and is attracted by the magnet in the cleaning member.
The toner accumulated on the cleaning member is rubbed away. When more than a certain amount of toner accumulates in the cleaning member, the action of gravity becomes stronger than the magnetic force in the cleaning member, and the toner is transferred from the cleaning member to the magnetic force of the rotating magnet 2 in the non-magnetic cylindrical member 3. The toner falls within the range of the toner, returns to the non-magnetic cylinder 3, and prepares for the next recording.

The operation of this embodiment will be explained based on FIG. 1D.

In the figure, t1 is the electrode length (displayed width), t'+ is the dummy electrode length, t2 is the cleaning magnet length, t3 is the length of the magnetic roller in the sleeve, and t.

is the length of the non-magnetic cylindrical sleeve, and tZ is the length of the toner anchoring member, which are set in the following relationship.

t2≦t3-5[+a+s]・・・・・・・・・・・・
(1) t1≦t2≦t, +zt; ・・・・・・
......(2) t3≧t4-2 [ll1m
] ・・・・・・・・・・・・ (3) Above formula (1)
In addition to setting the conditions, the distance gl! between the cleaning member and the non-magnetic cylindrical member. ; By setting L to 10+as to 150 mm, the toner that has fallen from the cleaning member falls within the range where the magnetic force of the mag roller on the non-magnetic cylinder acts, thereby preventing the toner from scattering due to falling.

In the embodiment of the cleaning method according to the present invention, as described above, the toner is attracted between the recording sheet and the cleaning member by the magnetic force of the cleaning magnet, which is a magnetic field generating means, and the cleaning is performed by rubbing the toners against each other. The magnetic force is weak at both ends, and not enough toner is collected. For this reason, the recording sheet may move slightly in the width direction due to device vibration, etc., resulting in poor cleaning, or if the toner stagnates around the toner anchoring members provided at both ends of the non-magnetic cylindrical sleeve 3, the stagnation occurs. There are problems such as toner adhering to the recording sheet and staining it. However, by providing a dummy electrode and grounding it under the condition of the above formula (2), the toner adheres to the recording sheet due to static electricity and becomes smeared, and the cleaning failure at the edges is eliminated.

Even if the toner is conveyed by the rotation of the mag roller and supplied to the electrode, the gap between the recording sheet and the electrode is very small (ioo~5
00 gm). Therefore, a large amount of toner that is not consumed for recording is transferred to the recording sheet without passing through the gap.
Or, it collides with toner that has been transported earlier and is stagnant, floating and scattering from both ends of the sleeve. Therefore, toner retaining members are provided at both ends of the sleeve to prevent toner from scattering from both ends. Furthermore, the toner transport area on the sleeve is set within the range of the magnetic force of the magnet roller so that the toner that hits the toner anchoring member does not float and is restrained by the magnetic force of the magnet roller. Therefore, by setting the condition of the above formula (3), toner floating and scattering from the sleeve end can be prevented.

(Effect) As explained above, the cleaning member is provided above the recording electrode or the toner transport member, and the interval between them is 10 to 1
Assuming a weight of 50m, t2≦t, -S, t, ≦t2≦t, +2L.

By setting t3≧t, −2, it is possible to prevent the toner from deviating from or scattering from the circulation path where recording, display, and erasing are repeated.

[Brief explanation of the drawing]

FIG. 1A is a longitudinal sectional view of an embodiment of the present invention, FIG. 1B is an internal front view of the same figure, and FIG. 1C is a detailed view of the cleaning end.
Figure 1D is an explanatory diagram showing each dimension of the device in Figure 1A, Figure 2A
The figure is a longitudinal sectional view of a conventional apparatus, FIG. 2B is an internal front view of the same figure, and FIG. 3 is an explanatory diagram showing the principle of image formation. In the figure, l... Toner 2... Magnet roller 3... Non-magnetic cylinder 4... Recording electrode 5... Recording member 6... Dielectric layer 7... Conductive layer 8... Cleaning Member 9...Magnet lO...Toner container 11...Recording medium indicating member 12...Body frame 13...Toner anchoring member

Claims (3)

[Claims] (1) A recording electrode having a large number of recording elements, means for supplying developer to the recording electrode, a drive circuit for applying a signal voltage to the recording electrode, and a recording member that moves relatively close to the recording electrode. , an image forming apparatus having an erasing member provided for erasing a recorded image, wherein the developer supply means is provided with a rotatable magnetic field generation means within a fixed non-magnetic cylindrical member; The erasing member is composed of a non-magnetic member and a magnetic field generating means, and the erasing member is installed above the developer supplying means at an interval of 10 to 150 mm, and the erasing member generates a magnetic field in the display width direction. An image forming apparatus characterized in that the length of the means is at least 5 mm or more shorter than the length of the magnetic field generating means in the developer supply means. (2) The length of the recording electrode in the display width direction is shorter than the length of the magnetic field generating means in the erasing member, and furthermore, dummy electrodes are provided at both ends of the recording electrode, which are attached to the main body of the apparatus. 2. The image forming apparatus according to claim 1, wherein the total length of the recording electrode and the dummy electrode is longer than the length of the magnetic field generating means in the erasing member. (3) Developer regulating means are provided in the circumferential direction on both sides of the non-magnetic cylindrical member, and the length of the cylindrical member inside the regulating means is shorter than the length of the magnetic field generating means. An image forming apparatus according to claim 1.