JPH0333885A - Image forming device - Google Patents

Abstract

PURPOSE:To erase an unnecessary toner image on a recording medium by providing different magnetic poles in positions which pinch a sliding frictional position of a sliding frictional member against the sliding frictional member. CONSTITUTION:Toner 7 is interposed between a recording electrode 9 and a recording medium 1, and the toner image is formed on the recording medium 1 by impressing voltage between an electrode 9 and the recording medium 1. Then the sliding frictional member 13 which slides and causes friction in the direction crossing with the traveling direction of the recording medium 1, and differing magnetic poles 16a and 16b are provided in positions which pinch the sliding frictional position of the sliding frictional member 13. Therefore, the spreading of toner 7 in the upper direction caused by the upper side magnetic pole 16b is suppressed and the toner can be pulled downward lower than a brush 13b caused by the lower side magnetic pole 16a. Thus, since the toner is not pooled over or in the downstream of the brush 13b, irregular image turbulance due to pooling of toner can be solved.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an image forming apparatus, particularly an image forming apparatus in which a voltage is applied between a plurality of recording electrodes and a recording medium, and image forming particles (toner) are adhered to the recording medium during that time. The present invention relates to an image forming apparatus such as a printer or a display device i.

[Prior art] Such a six-image forming method is disclosed in Japanese Patent Publication No. 51-467.
There is a method known from Publication No. 07, etc. In this method, as shown in FIG. 2, conductive magnetic toner 7 is conveyed around the outer periphery of a non-magnetic cylinder 6 by the magnetic field of a rotating magnet 8. At this time, a voltage corresponding to the image information is applied to the conductive layer 1b of the recording medium 1 by the recording control unit 10 to the recording electrodes 9 densely arranged along the axial direction on the non-magnetic cylinder 6, and the recorded information is Corresponding to this, toner is attached to the insulation F 1 a of the recording medium 1 to display an image.

Further, as a further development of the above, a display device has been devised using the recording electrode. FIG. 3 shows a cross-sectional configuration diagram of the entire device. The toner 107 is conveyed onto the recording electrode 109 by the rotation of the magnetic roller 117, and toner may or may not adhere to the recording medium 101 at a position facing the recording electrode 109 depending on the signal from the recording electrode 109. form an image. For example, when a signal voltage of +40 V is applied from the recording control section 110, image formation is performed through a process in which toner adheres to the recording medium lot and does not adhere to the opposite side of the OV. After the image is formed and displayed in this manner, the image is erased by the cleaning member 113.

Now, to describe this cleaning mechanism in detail, it is shown in FIG.
Reference numeral 13 is fixedly attached to the back plate of the main body of the apparatus via a member. The cleaning member 113 includes a cleaning body 113a and a soft, conductive brush 113 as an erasing means.
The brush 113b is positioned so as to rub the recording medium lot at an appropriate angle (θ) and distance, and the cleaning member 113 is connected to the ground or a voltage of several volts (cleaning bias i 20
) is applied. When the recording medium 101 moves downward from the cleaning section, the toners 1 to 107 forming an image on the recording medium 101 are rubbed by the brush 113b on the recording medium 101, or at that time, the cleaning member 113 is electrically neutralized by applying a ground or cleaning bias, and is attracted to the tip of the brush 113b by the magnet 116.
It falls due to its own weight, is recovered by the image forming unit 5104, and is used again for image forming.

[Problems to be Solved by the Invention] However, in such a conventional example, when the N or S magnetic pole of the magnet 116 is placed facing the cleaning member 113 as shown in FIG.
The toner 107 accumulated on b is attracted to the recording medium 101, and toner collection is effective. However, since the lines of magnetic force tend to open toward the cleaning member 113, the toner 107 spreads along the lines of magnetic force toward the direction of the magnet 116 and accumulates on the brush 1i3b, as shown in FIG. Toner also accumulates on the downstream side of the brush 113b along the lines of magnetic force. As a result, a large amount of toner 10
7 aggregates with a weak force and falls irregularly in lumps due to its own hair. And the non-magnetic cylinder 106
The toner 107 is transported to the recording medium 101 side at 100 h, and regardless of the recording voltage from the recording control unit 110, the toner 107 is rubbed on the recording medium 101 and adheres to the recording medium 101, and the display surface is For example, there was a problem in that it appeared in spots.

This is a problem that appears as speckled shading, especially when intermediate density H images or halftones are expressed using pseudo gradation from dotted lines.

[Means for Solving the Problem] The present invention removes such unnecessary toner images on a recording medium by interposing toner between a plurality of recording electrodes and the recording medium, and by interposing the toner between these electrodes and the recording medium. In an image forming apparatus that forms a toner image on a recording medium by applying a voltage between the media, in order to erase unnecessary toner images on the recording medium,
A sliding member that slides against the recording medium in a direction that intersects with the moving direction thereof, and a Wj retaining member with a different magnetic pole at a position sandwiching the sliding position of the sliding member indicated by - through the recording medium. This is to prevent the magnetic member from being disposed.

[Function] In the present invention having the above configuration, different magnetic poles are arranged in line with each other along the recording medium conveyance direction, so that the recording medium and the toner can be prevented from forming spikes. It will be in a sleeping state. Therefore, the spikes of toner do not extend toward the erasing means. Furthermore, by sandwiching the image erasing means between magnetic poles of different polarities, the upper magnetic pole can suppress the toner from spreading upward.

The lower magnetic pole allows the toner to be strongly drawn below the brush. Therefore, the toner does not accumulate on the brush and the toner always falls easily. Furthermore, since the lines of magnetic force do not extend downward, toner does not accumulate below, making it possible to eliminate toner lumps that would stain the formed toner image.

[Example] The present invention will be explained below based on illustrated embodiments.

FIG. 1 shows a first embodiment of an image recording apparatus according to an unreleased image 11. In the same figure, l is a recording medium, and the recording medium 1 is a pair of rollers 2.317 arranged above and below.
The burden is being passed on to JI.

At a position facing the roller 3, there is a recording medium 1,
, l: 4 image forming stages are provided. As this image forming means 4,
The information disclosed in Publication No. 707, etc. is used, and is as described above. That is, as shown in FIG. 2, the conductive magnetic toner 7 is conveyed around the outer periphery of the non-magnetic cylinder 6 by the magnetic field of the magnet 8 that rotates once. In this section, a recording control unit 10 applies a voltage corresponding to image information to recording electrodes 9 densely arranged along the axial direction on a non-magnetic cylinder 6 on a conductive layer ib of the recording medium.
toner is applied to the insulating layer 1a of the recording medium 1 in accordance with the recorded information to display an image.

The image displayed on the recording medium I is displayed on a display section 12 formed on the entire surface of the main body of the apparatus. On the back side of the recording medium 1, a cleaning member 13 for erasing the image displayed on the recording medium 1 is fixedly attached to the back plate ila of the apparatus main body 11 via a member 14. The cleaning member 13 is composed of a cleaning body 13a and a soft, conductive brush 13b as an erasing means, and is positioned so that the brush 13b rubs against the recording medium 1 at an appropriate angle and distance. This cleaning member is made of materials such as carbon m-fibers, soft plastics (polyethylene, polypropylene) that have conductivity due to composites, urethane rubber, silicone, and the like. Also, the cleaning member 1 is placed between the recording medium l.
A non-magnetic member 15 and magnets 16a and 16b for supporting the recording medium l are disposed at a position facing the recording medium l. In this embodiment, in order to completely eliminate the electric charge generated on the recording medium 11, the electric charge having the opposite polarity to the electric charge generated on the recording medium l is removed through the cleaning member 13 using the electric discharge source 20. It is configured to apply JE.

FIG. 6 is an enlarged sectional view of the recording medium 1 applied to this embodiment. In the figure, Ia is a surface layer made of a transparent material whose main component is butyral resin, phenol resin, or urethane shelf, and IB provided on the lower surface of the surface layer IA is titanium oxide (Ti02), oxidized It is a white layer made of a white inorganic substance such as aluminum (A1203) and an adhesive (acrylic resin, plastic resin). Further, 10 located at the bottom layer of the recording medium 1 is a base material made of plastic resin such as polyethylene terephthalate, polyethylene, polypropylene, etc., and the upper surface thereof is made of aluminum or 1. T, 0
．． Conductive layer 1c deposited with (indium and tin oxide)
is provided.

In the above configuration, when erasing a visualized toner image, the brush 13b is disposed between the magnets 16a and 16b as shown in FIG. Since the toner 7 tends to extend along the lines of magnetic force created by the magnets lea and 16b that are almost parallel to the conveying direction of the recording medium l (see FIG. 8), it spreads thinly over the recording medium l to form spikes of toner. Brush 1 because it doesn't.
It becomes difficult to accumulate on 3b. In addition, the recording medium 1 and the brush 13
Since the magnetic pole 16a is disposed below the rubbing portion with the brush 13, the rubbed toner 7 is drawn into the lower magnetic pole 16a rather than staying on the brush 13, and is transferred to the recording medium 1.
By constantly falling from the brush 13b due to the movement of the toner 7 and its own weight, it is possible to prevent the formation of lumps due to agglomeration of the toner, and it is possible to eliminate image stains caused by rubbing between the toner lumps and the recording medium l. It becomes possible. Also, brush 13
The upward scattering of 1 henna caused by the rebound of the magnetic field b is also eliminated because it is attracted by the upper magnetic pole 16b.

FIG. 9 shows a second embodiment of the invention. t5
In Fig. 9, the difference from the first embodiment is that the magnet 16 facing the image erasing means is made single, and the direction of the magnetic poles is changed. The parts will be described with the same reference numerals.

In this embodiment, the above object can be achieved by arranging the magnets 16 as shown in FIG. In other words, by arranging the image erasing device with the magnets 16 facing each other in the first stage so that the direction of the magnetic poles is the same as the conveyance direction of the recording medium l as shown in FIG. 9, even a single magnet can be used as shown in the first embodiment. It is possible to generate lines of magnetic force along the recording medium 1, and by positioning the brush 13b in the lines of magnetic force, the same effect as that shown in the first embodiment can be obtained. Therefore, there is an advantage that cost reduction can be achieved by reducing the number of Cm stones.

No. 10 IJ shows a third embodiment of the present invention.

, the magnet 1 facing the image erasing means in FIG.
This device is the same as the second embodiment except that 6 is made single and the magnetic plate 17 is removed, and the same parts will be described with the same reference numerals.

In this embodiment, the above object can be achieved by bringing the magnet 16 and the magnetic plate 17 into close contact with the lower part of the magnet 16. That is, as shown in FIG. 10, the magnetic poles are arranged in the same manner as in the second embodiment, and the magnetic plate 17 is adhered so as to be in close contact with the magnetic poles on the lower side of the magnet 16. It is now possible to concentrate the magnetic lines of force on the side surface of the magnetic plate 17, and the toner can be drawn downward more strongly, resulting in the advantage that toner accumulation on the downstream side of the brush 13b can be further reduced.

FIG. 11 shows a fourth embodiment of the present invention. In FIG. 11, the device is the same as the second embodiment except that the magnet 16 facing the image erasing means is single and has a magnetic plate 17a and a magnetic plate 17b, and the following parts are the same. are given the same reference numerals in the explanation.

In this embodiment, the above object can be achieved by bringing the magnet 16 and the magnetic plates 17a and 17b into close contact with the lower and upper magnetic poles of the magnet 16, respectively. In other words, as is clear from FIG. 11, in this embodiment, in addition to the configuration in which the magnetic plate is closely attached to the bottom of the magnet as shown in the third embodiment, a magnetic plate is also attached to the top of the magnet. It is structured. By using such a configuration, the magnetic lines of force that were spreading above the magnet 16 are concentrated on the side surface of the magnetic plate 17b, thereby making the layered magnetic lines of force more dense on the recording medium l and pushing the toner more strongly towards the recording medium l side. This has the advantage that toner can be attracted to the brush 13b and the amount of toner accumulated on the brush 13b can be greatly reduced.

Furthermore, since the magnetic lines of force are concentrated by the upper magnetic plate 17b, the toner 7 that is about to scatter in the -E direction is also held, thereby preventing toner scattering.

FIG. 12 shows a fifth embodiment of the present invention. The 12th ('13) device is the same as the second embodiment except that it has a plurality of magnets facing the image erasing means and has a magnetic plate 17a and a magnetic plate 17b, and the same parts are used hereinafter. are given the same reference numerals in the explanation.

In this embodiment, for example, the number of magnets facing the image erasing means is two, and the magnets 16a and 16b are arranged with the same magnetic pole or adjacent to each other as shown in FIG. Magnetic plate 17a and magnetic plate 17b
By sandwiching the C magnets 16a and 16b, lines of magnetic force are transferred to the magnetic plates 17a and 17b with even stronger magnetic flux density.
Since the toner 7 can be emitted from the side of the recording medium 1, and the toner 7 can be strongly drawn toward the recording medium 1, it is clear that this is effective for the above purpose for the reason 1) explained in the fourth embodiment.

The magnet used in this example is a rod-shaped plastic magnet with a cross section of 6 x 6 mm and a magnetic flux density of about 800 Gauss at the maximum directly above the magnetic pole. -2 plates were used. However, in the present invention, there is no need to be particular about these materials #4 and numerical values.

It should be noted that the present invention is applicable not only to the display apparatus described above but also to image forming apparatuses such as printers and copying machines that use such an image forming principle.

[Effect of the invention] In the unreleased II having the above configuration and operation,
Since toner does not accumulate on the brush or on the downstream side thereof, it is possible to eliminate irregular image stains caused by toner accumulation, and furthermore, it is possible to prevent toner from scattering in the L direction from the brush at the same time. play. In addition, since the amount of toner accumulated in the brush portion is small, the surrounding area is not soiled while replacing the recording medium, making it possible to realize an apparatus that is easy to handle.

[Brief explanation of drawings]

Fig. 1 is an overall view of the apparatus according to the first embodiment of the present invention, Fig. 2 is an explanatory view showing an image forming method, Fig. 3 is a sectional view of the apparatus of the conventional example, Fig. 4 is an explanatory view of the cleaning mechanism, and Fig. 5 is an explanatory view of the cleaning mechanism. The figure is a partial enlarged view of the area around the conventional cleaning section, Figure 0'S6 is an enlarged cross-sectional view of the recording medium, Figure 7 is an explanatory diagram of the first example of unreleased IJj, and Figure 8 is an explanatory diagram of the state of magnetic lines of force. FIG. 9 is an explanatory diagram of the second embodiment of the present invention. FIG. 10 is an explanatory diagram of the third embodiment of the present invention, FIG. 11 is an explanatory diagram of the fourth embodiment of the present invention, and FIG. 12 is an explanatory diagram of the fifth embodiment of the present invention. In the figure, 1 is a recording medium 4, an image forming means 6, a non-magnetic cylinder 7, a toner 8, a rotating magnet 9, a recording electrode io, and a recording system! 1 part 11 is the main body 12 is the display part 13 is the cleaning member 13a is the cleaning main body 13b is the brush 14 is the attachment member 15 is the non-magnetic member J6, 16a, 16b is the magnet 17. 17a, 17b is the magnetic plate 20 is the static elimination Indicates the power supply for

Claims (1)

[Claims] (1) In an image forming apparatus in which toner is interposed between a plurality of recording electrodes and a recording medium and a voltage is applied between these electrodes and the recording medium to form a toner image on the recording medium. In order to erase a toner image, a sliding member that rubs against the recording medium in a direction perpendicular to the moving direction thereof, and a sliding member with different magnetic poles at positions sandwiching the sliding position of the sliding member. and a magnetic member disposed via the recording medium.