JPS62287267A - Image forming device - Google Patents

Abstract

PURPOSE:To enable wiring from the upstream side of a recording part and to easily form an image recording part by supplying toner through an opening part. CONSTITUTION:The toner for image formation is supplied to an image recording part through the opening 11. There is an irregularity in the amount of toner corresponding to the pitch of the opening right after the toner passes through the opening 11, but the irregularity is nearly eliminated after the toner moves by distance 2-3 times pitch of the opening. Further, a slope which is slow enough not to impede the conveyance of the toner is provided on the upstream side in the moving direction of the toner, so a printing plate is easily arranged in parallel. This results in that the printing late need not be folded sharply nearby a magnetic plate 9, and the printed plate is cut at a folding point, thereby eliminating a deviation from the straight line of an electrode shape and an irregularity in height.

Description

Detailed Description of the Invention 3. Detailed Description of the Invention (Industrial Application Field of the Invention) The present invention relates to an image forming apparatus, in particular, to apply a voltage between a recording electrode and a recording medium, and to remove image forming particles (toner) between the recording electrode and the recording medium. ) on a recording medium.

(Prior art) As such an image forming method, Japanese Patent Publication No. 51-4670
There is a method known from Publication No. 7. This method is the second
As shown in the figure, a conductive magnetic toner l 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, and the conductive magnetic toner l is transferred to a recording medium 5 having an imageless layer on its surface. An image is formed by applying a voltage between the layer 7 and the recording electrode to cause toner to adhere to the recording medium.It has a very hour wheel configuration and has various advantages, but its major disadvantage is that it cannot be driven in segments. In other words, it may be necessary to continue applying a voltage for image formation to all recording electrodes independently.

Therefore, it is necessary to provide the same number of lead lines as recording electrodes so as not to interfere with toner transport.

Conventionally, for this purpose, it has been considered to extend the lead wire over the non-magnetic cylinder 3 and take it out in the axial direction.
An example is shown in the figure. In this example, the recording electrodes 4 are connected in unit units to lead wires 8 made of a flexible printed circuit board, and the lead wires are bent on the nonmagnetic cylinder 3 and taken out in the axial direction. However, with this method of dividing and connecting each block, it is difficult to achieve high accuracy in the joints of the electrodes, and the process of connecting the lead wires, which are taken out in the axial direction in an overlapping manner, to the drive circuit becomes complicated. Another idea is to integrate the recording electrode and drive circuit and mount it on a non-magnetic cylinder, but it is difficult to mount all the necessary parts on a non-magnetic cylinder to a thickness that does not interfere with toner transport. Accompany.

Another problem is the large number of connections between the recording electrodes 4 and the drive circuit, and in order to avoid this, there is an idea to integrate the recording electrodes into a printed circuit board, an example of which is shown in FIG. Here, a magnetic plate 9 is provided to pass through the cylinder 3 in the axial direction, and a flexible printed circuit board 8 is pasted thereon. Connection with the drive circuit is made in the same manner as in FIG. The part on top of the magnetic plate 9 plays the role of the recording electrode 4, but the disadvantage is that it is difficult to accurately bend the printed circuit board 8 near the magnetic plate 9, and the electrode shape may deviate from the straight line or be There is a point where the image quality tends to become uneven and the image quality deteriorates.

(Problems to be Solved by the Invention) The present invention eliminates the drawbacks of the above-mentioned conventional examples and provides a novel connection method between recording electrodes and drive circuits.

(Means for Solving the Problems) The image forming apparatus of the present invention includes a rotating magnet, a non-magnetic cylindrical member covering the rotating magnet, and a convex portion provided in the axial direction on the surface of the cylindrical member. The flexible circuit board has a gentle angle on the upstream side of the direction and a steep angle on the downstream side, and a flexible circuit board with the ends of the electrode group on one side is placed on the cylindrical member. The flexible circuit board is attached from the upstream side in the toner transport direction so as to be aligned with the top of the flexible circuit board, and an opening is provided in the flexible circuit board along the separation position from the cylindrical member.

(Embodiment) FIG. 1 shows an embodiment of the present invention in which a magnetic plate 9 is attached in the axial direction to a non-magnetic cylinder 3 containing a rotating magnet. The position of the magnetic plate 9 is approximately the image recording position. The magnetic plate 9 used has a thickness of 0.02 to 1 mm and a height of 0.5 to 2 mm. The magnet inside the cylinder 3 is rotated so that the toner moves in the direction shown by arrow A.

The upstream side of the magnetic plate 9 in the direction of toner movement is molded with resin or the like so that it connects to the non-magnetic cylinder 3 with a gentle slope that does not interfere with toner conveyance, and the downstream side is shaped so that the toner moves closer to the recording medium. Make it at a steep angle so you can move away quickly.

The recording electrodes 13 are arranged at one end of the flexible printed circuit board 1o, and openings 11 are provided at regular intervals between the flexible printed circuit board 1o and the drive element 12. Flexible printed circuit board 1
0 is adhered onto the non-magnetic cylinder 3 such that the end where the recording electrode 13 is provided is aligned with the downstream side of the magnetic plate 9 and separated at the opening 11. Toner for image formation is in opening 1
1 and is supplied to the image recording section. Immediately after passing through the apertures 11, there is an unevenness in the amount of toner corresponding to the pitch of the apertures 11, but when the toner moves a distance 2 to 3 times the aperture pitch, the unevenness becomes almost non-uniform.The aperture pitch is 0.2 to 10 m
There is no problem in the range of about m. The ratio of the openings to the non-openings (distance) expressed as a length ratio is larger, the smoother the toner movement, but it can be about 172 to 2 times. As the processing means, mechanical means such as drilling and punching, chemical means such as etching, electrical discharge machining, laser beam machining, etc. can be selected depending on the material used and the size of the hole.

Further, as described above, since the upstream side in the toner movement direction has a gentle slope to the extent that it does not hinder toner conveyance, it is easy to arrange the printed board 8 in parallel.

This means that there is no need to sharply bend the printed board 8 near the magnetic plate 9 as in the past, and by cutting the bending point of the pint plate 8, the electrode shape will not deviate from the straight line or the height will be uneven. do not have.

(Other Embodiments) In FIG. 1, the magnetic field is concentrated on the magnetic plate 9, a toner plan is formed on the recording electrode 13, and an image is recorded. Although the image quality deteriorates, a usable image can be obtained.

Further, in order to prevent a short circuit between the magnetic plate 9 and the recording electrode 13, the surface of the magnetic plate 9 may be coated with an insulating coating.

FIG. 1 shows an example in which a flexible printed circuit board is used to facilitate wiring between the recording electrode and the drive circuit.
The electrodes and the output end of the drive circuit may be connected by wiring one by one. In this case, toner can circulate through the gaps between the lines. In this case, wiring work is required, but the drive circuit can be installed close to the non-magnetic cylinder along its longitudinal direction, as in the case of Fig. 1, so it does not take up extra space and the device It can be kept compact in size.

In this case, by making the cross-sectional area (recording width x gap) between the recording electrode and the recording medium equal to or less than the cross-sectional area of the opening of the printed board 8, toner will not get stuck between the recording electrode and the recording medium. . In this experiment, when the cross-sectional area was kept the same, toner clogging was not observed for a long period of time, and it was possible to always maintain a good image.

(Effects) As explained above, by supplying toner through the opening, wiring can be done from the upstream side of the recording section. As a result, when configuring the recording section using a printed wiring board, the end of the printed wiring board can be used as the rear end of the recording section, unlike the conventional case where the printed wiring board is placed at a steep angle on the downstream side of the recording section. There is no longer a need to bend it. As a result,
The manufacturing of the image recording section becomes easier, and at the same time, the precision of the shape is improved, and the image quality is greatly improved. At the same time, connection between a large number of recording electrodes and drive circuits becomes extremely easy as no wiring work is required.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of the image recording section of the embodiment of the present invention;
FIG. 2 is a schematic sectional view showing an example of an image recording method to which the present invention is applied, FIG. 3m is a perspective view of a conventional recording electrode, and FIG. 4 is a sectional view of a conventional electrode. In the figure, 1 is a toner, 3 is a non-magnetic cylinder, 9 is a magnetic plate, and 10 is a flexible printed circuit board.

Claims (1)

[Claims] A rotating magnet, a non-magnetic cylindrical member covering it, and a convex portion in the axial direction are provided on the surface of the cylindrical member, and this convex portion has a gentle angle on the upstream side in the toner transport direction and a steep angle on the downstream side. and affixing a flexible circuit board with the ends of the electrode group on one side onto the cylindrical member from the upstream side in the toner transport direction so that the end of the electrode group is aligned with approximately the top of the convex portion on the surface of the cylindrical member; An image forming apparatus characterized in that the flexible circuit board is provided with an opening along a separation position from the cylindrical member.