JPH0622845Y2 - Image forming device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Use of the Invention) The present invention comprises a recording sleeve in which a large number of electrode needles are linearly arranged in the axial direction of the peripheral surface, and a voltage is applied to each electrode needle according to image information. The present invention relates to an image forming apparatus which forms an image on a recording medium by adhering toner onto the recording medium according to this voltage.

[Conventional technology]

An image forming apparatus of the above type is disclosed, for example, in JP-A-55-127.
Japanese Patent Laid-Open No. 578 discloses that the output of an external recording device or the output of a keyboard or the like is converted into an electric signal and input, and a chart, a character, or the like is displayed on an output display unit. In this case, when an electric field is generated between the recording sheet and the electrode needle array on the recording sleeve, the conductive and nourishing toner carried on the recording sleeve and riding on the electrode needle array is electrically charged on the recording sheet. It is adsorbed by the attractive force to form an image.

FIG. 5 shows an example of such an image forming apparatus. In the figure, a two-dot chain line 1 indicates the main body of the apparatus, and 2 indicates a transparent image output display plate such as glass or acrylic. An endless belt-shaped recording sheet 3 is arranged behind the display plate 2, which is stretched between an upper roller 4 and a lower roller 5 and is connected to one of the rollers 4 and 5 (not shown). ) To move in the direction indicated by arrow A. A recording roll 6 is arranged at the bottom of the main body of the apparatus.

As shown in FIG. 6, the recording sheet 3 comprises a surface layer 3a recorded with TiO ₂ , A ₂ O _{3 and the} like and a conductive layer 3b obtained by vapor-depositing aluminum on a polyester film, and the conductive layer 3b is grounded. . As shown in FIG. 6, the recording roll 6 is composed of a recording sleeve 6a and a rotary magnet 6b disposed inside the recording sleeve 6a, and the rotary magnet is magnetized as shown in FIG. On the peripheral surface of the recording sleeve 6a, a ferromagnetic member 6c extending in the axial direction of the sleeve is attached so as to have substantially the same length as the sleeve, and a large number of electrodes linearly arranged in the axial direction of the peripheral surface of the sleeve. A needle 7 is mounted on the ferromagnetic member 6c.

An image information input circuit 8 is connected to the electrode needles 7, and a plurality of the electrode needles are arranged according to the image density to form an array. The conductive magnetic toner 9 is supplied to the recording sleeve 6a as shown in FIG.

During operation of the apparatus, the rotary magnet 6b is rotated in the direction indicated by the arrow C, the conductive magnetic toner 9 forms a spike on the surface of the recording sleeve 6a, and in the direction indicated by the arrow B according to the rotation of the rotary magnet 6b. Moving. The spikes are carried on the electrode needles 7 and, when they reach the ferromagnetic material 6c, they come to the position closest to the surface layer 3a of the recording sheet 3. At this time, when a signal is input from the input device 8 so as to apply a predetermined voltage to the control circuit 10, a positive voltage, for example, is applied to the electrode needle of the electrode needles 7 designated to apply the voltage, and recording is performed. A negative potential is induced on the back side of the surface layer of the sheet 3. Here, the conductive magnetic toner 9 jumps onto the surface layer 3 a of the recording sheet 3.
In this way, the signal from the input device 8 is transmitted to the control circuit 10.
Every time it is input to the recording sheet 3, digital signals by the conductive magnetic toner are displayed in a line in the width direction of the recording sheet 3. Thus, an image is formed on the recording sheet 3 as the recording sheet 3 moves, and this image is displayed on the display plate 2.

[Problems to be solved by the invention]

In the above recording apparatus, the gap between the electrode needle 7 and the recording sheet 3 has a great influence on the image density and the resolution. In particular, when the recording sleeve 6a is made long in order to display a large screen, the recording sleeve may bend and the uniform gap cannot be maintained over the entire area of the electrode needle, resulting in an uneven image. There is. Further, when the recording roller 6 is replaced due to damage of the electrode needles, the recording sheet 3 is replaced, or the electrode needle 7 is cleaned, the gap between the recording sheet 3 and the electrode needle 7 is not uniform. Adjustment may be time-consuming.

[Means for solving problems]

The present invention is provided with a recording sleeve having a large number of electrode needles linearly arranged in the axial direction of the circumferential surface as a means for solving the above-mentioned drawbacks of the conventional apparatus, and applying a voltage to each electrode needle according to image information. Then, in an image forming apparatus that forms an image on a recording medium by adhering toner onto the recording medium according to this voltage, the surface of the recording sleeve is substantially opposite to the surface on which the electrode needles are provided and It is an object of the present invention to provide an image forming apparatus characterized in that a pressing means whose contact force can be adjusted is provided so that a gap between an electrode and a recording medium can be adjusted.

[Action]

According to the present invention, the recording roller 6 whose both ends are supported by the main body side
By providing one or a plurality of adjusting means in the inner part of the recording medium, the deflection of the recording roller can be removed and the gap between the recording sheet and the electrode needle can be adjusted, and the gap between the recording sheet and the electrode needle can be made uniform. It is possible to maintain and prevent the occurrence of non-uniform images.

〔Example〕

Hereinafter, the present invention will be described in detail with reference to the illustrated embodiments.

1 and 2 show an embodiment of the present invention, in which 5 is a lower roller similar to that shown in FIGS. 5 and 6,
Reference numeral 6 denotes a recording roller.

The lower roller 5 is rotatably supported by a bearing 11, and a motor M1 is connected to one end of its rotation shaft. Reference numeral 3 denotes a recording sheet similar to that shown in FIGS.

The recording roller 6 is composed of a recording sleeve 6a and a rotating magnet 6b arranged inside the recording sleeve 6a, similar to that shown in FIG.
On the peripheral surface of the recording sleeve 6a, a large number of electrode needles 7 arranged linearly in the axial direction are provided.

A spacer roll 12 made of a wear-resistant material such as high-density polyethylene is rotatably attached to both ends of the recording sleeve 6a, and is arranged between the developing container 13 and both ends of the recording sleeve. By the action of the pressed spring 14, the spacer roll 12 is brought into contact with the surface of the lower roller 5 to keep the distance between the lower roller 5 and the recording sleeve 6 constant, and thus the recording sheet 3 and the electrode needle 7 are The gap between them is kept constant. The rotating shaft 1 is located at the center of the rotating magnet 6b.
5, the rotary shaft 15 is rotatably supported by bearings 16 at both ends in the recording sleeve 6a, and the motor M2 is connected to one end of the rotary shaft 15 to rotate the rotary magnet 6b at a predetermined speed.

On the opposite side of the surface of the recording sleeve 6a on which the electrode needles 7 are provided, a pressing means 17 for contacting the sleeve 6a is provided. In the embodiment shown in FIG. 1, the pressing means 17 is, as shown in FIG. 2, made up of an adjusting bolt 19 screwed into a screw portion 18 provided integrally with the developing container 13, and its tip portion 19a is The recording sleeve 6a is rotatably loosely fitted in a receiving member 20 provided in the lower center part. In order to prevent the toner from entering the screw portion 18 during the operation of the apparatus, a seal member 21 slidably fitted in the adjusting bolt 19 in a close contact state is mounted on the screw portion 18.

In the above apparatus, when the gap between the recording sheet 3 and the electrode needle 7 is widened due to the bending of the sleeve at the center of the recording sleeve 6a, the recording sleeve 6a is lifted by rotating the adjusting bolt 19 clockwise, for example. The gap can be made uniform over the entire area. On the contrary, when the gap is narrow, the central portion of the recording sleeve 6a is pulled downward by rotating the adjusting bolt 19 counterclockwise, so that the gap can be uniformly adjusted over the entire area.

FIG. 3 shows another embodiment of the present invention. In this embodiment, the pressing means 17 provided on the opposite side of the surface of the recording sleeve 6a on which the electrode needles are provided has a recording sleeve at one end.
The adjusting member 22 fixed to the lower part of 6a and protruding at the other end to the outside of the developing container 13 and bent in a hook shape, and the screw portion provided in the developing container 13 through the hooked part of the adjusting member The adjusting bolt 23 is screwed to the. A seal member 24 made of an elastic member such as rubber is provided to prevent the toner from leaking from the bottom surface of the developing container and the toner from adhering to the screw portion of the adjusting bolt.

The operation of the pressing means shown in FIG. 3 is the same as that shown in FIGS.

FIG. 4 shows still another embodiment of the present invention. In this embodiment, a rib 25 that abuts the recording sleeve 6a is provided on the bottom of the developing container 13, and the tip end of the adjusting bolt 27 that is screwed into the screw portion provided on the machine frame 26 of the apparatus is the lower end of the rib 25. And the pressing means 17 is configured. In this embodiment, the position of the bottom of the developing container 13, that is, the height of the central portion of the recording sleeve 6a can be adjusted via the rib 25 by the rotation angle of the adjusting bolt 27.

The receiving member 20, the adjusting member 22, and the rib 25 that abuts on the sleeve surface, which are provided on the recording sleeve surface described above, have a shape that prevents the flow of the magnetic toner moving on the sleeve surface as much as possible. Is desirable.

Further, the position where the receiving member 20, the adjusting member 22, the rib 25, or the like comes into contact with the recording sleeve 6a should be on the substantially opposed surface of the electrode needle 7 so that the gap with the recording sheet can be adjusted efficiently. When the recording sleeve is not arranged vertically downward, the gap with the recording sheet can be adjusted by pushing the recording sleeve from the side.

[Effect of device]

As described above, when the recording sleeve is long and the central portion bends, the height adjustment means for the sleeve is provided so as to contact the central portion of the sleeve, so that the electrode needle 7 and the recording sheet 3 provided on the surface of the recording sleeve. The gap between and can be kept uniform over the entire area. Therefore, the image on the recording sheet is also uniform.

In particular, the present invention is effective when a flexible recording sleeve made of resin is used to reduce the weight of the display device and reduce the cost.

Although the height adjusting means is provided at the center of the recording sleeve in the above description, if the recording sleeve is very long, the adjustment can be easily and accurately performed by providing a plurality of adjusting means.

[Brief description of drawings]

1 is a sectional view showing the construction of a lower roller, a recording roller and a pressing means in an embodiment of the image forming apparatus according to the present invention, and FIG. 2 is an enlarged sectional view of the pressing means shown in FIG. 1, FIG. Is a sectional view showing a modified example of the pressing means, FIG. 4 is a sectional view showing another modified example of the pressing means, FIG. 5 is a sectional view showing the entire image forming apparatus, and FIG. 6 is shown in FIG. FIG. 3 is a cross-sectional view showing a relationship between a lower roller and a recording roller in the apparatus. 1 ... Device main body, 2 ... Display plate 3 ... Recording sheet, 4 ... Upper roller 5 ... Lower roller, 6 ... Recording roller 6a ... Recording sleeve, 6a ... Rotating magnet 7 ... Electrode needle, 8 ... Image information input circuit 9 ... Conductive magnetic toner, 10 ... Control circuit 11 ... Bearing, 12 ... Spacer roll 13 ... Development container, 14 ... Pressing spring 15 ... Rotating shaft, 16 ... Bearing 17 ... Pressing means, 18 ... Screw part 19 ... Adjusting bolt, 20 ... Receiving member 21 ... Seal member, 22 ... Adjusting member 23 ... Adjusting bolt, 24 ... Seal member 25 ... Rib, 26: Machine frame 27: Adjustment bolt

Claims (1)

[Scope of utility model registration request] 1. A recording sleeve provided with a large number of electrode needles linearly arranged in an axial direction of a peripheral surface, a voltage is applied to each electrode needle according to image information, and toner is recorded on a recording medium according to the voltage. In an image forming apparatus for forming an image on a recording medium by adhering the same, a pressing means capable of adjusting a contact force with respect to a sleeve peripheral surface is provided substantially on the opposite side of the surface of the recording sleeve on which the electrode needle is provided, An image forming apparatus characterized in that a gap between a recording medium and a recording medium can be adjusted.