JPS6015944B2 - Photoconductor cleaning device for electronic copying machines - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a photoreceptor cleaning device for an electronic copying machine.

The process of forming a static latent image on a photoconductor, supplying powder toner to the static latent image to develop it, and transferring the resulting visible image onto a recording sheet is performed using the same photoconductor. In a repeating type electronic copying machine, after a visible image is transferred onto a recording sheet, the toner remaining on the surface of the photoconductor is removed from the surface of the photoconductor before a new latent image is formed on the photoconductor. A so-called cleaning step is absolutely necessary.

FIG. 1 shows an example of a conventionally known photoreceptor cleaning device. That is, the rotating body 2, which has a brush 21 formed on the circumferential surface of the cylinder 20, such as a fur brush, transfers a visible image transfer portion and a main charging portion to the circumferential surface of the drum-shaped photoreceptor 1. In between, the brush 21
is disposed in the direction of the rotation axis 22 of the cylinder 20 so as to be in contact with the surface of the photoreceptor 1 in a band-like manner. The casing 3 encloses the rotating body 2 together with the photoreceptor 1, and there is an opening for air intake between the end of one leg of the photoreceptor and the surface of the photoreceptor 1. An exhaust port is provided on the opposite side of the casing 3 from the photoreceptor 1 with respect to the rotating body 2, and a filter chamber 4 is disposed in series with the exhaust port. A filter 5 is provided inside the filter chamber 4 and connected to the exhaust port. The filter 5 is formed of a net or cloth whose mesh is smaller than the particle size of the toner. A fan 6 is provided near the outlet of the filter chamber 5. Furthermore, a thin plate 8 is fixedly provided inside the casing 3 so that its longitudinal direction is parallel to the ball direction of the cylinder 20 and one side twill in the longitudinal direction contacts the brush 21 . The rotation axis of the photoreceptor 1 is the rotating shaft 22 of the cylinder 20.
, and both of them, that is, the photoreceptor 1 and the rotating body 2, rotate in the same direction.

Cleaning of the photoreceptor 1 by this device is performed as follows.

That is, when the device is operated, the rotating body 2 is driven by any known rotating means to rotate at high speed in the direction of the arrow, and the fan 6 rotates. The fan 6 is a Fuji-style fan, and discharges the air inside the filter chamber 4 to the outside. Then, the air passes through the inside of the casing 3 from the intake closing part,
An air flow is created which passes through the filter 5 and flows to the outside from the outlet of the filter chamber 4. After the visible image formed on the surface of the photoreceptor 1 is transferred onto the recording sheet in the visible image transfer section, the surface portion to which the residual toner is attached is
The rotating body 2 is moved by the rotation of the photoconductor 1 in the direction of the arrow.
When the residual toner reaches the position where it contacts the surface, the residual toner is wiped off from the surface by the brush 21 that rotates at high speed and contacts the surface, and some of the residual toner reaches the vicinity of the intake closing part.
Some of it is repelled and the other part adheres to the brush 21. The toner that has been repelled to the vicinity of the intake port is sucked into the casing 3 by the air flow, and
After being conveyed inside, the air stream is captured by the filter 5 just as it passes through it. Further, the toner adhering to the brush 21 is sent into the casing 3 as the rotating body 2 rotates, is repelled by the thin plate 8, is separated from the brush 21, is conveyed toward the filter 5 by the air flow, and is captured. be done. However, such a photoreceptor cleaning device has the following problems. That is, the toner adhering to the brush 21 remains unseparated from the brush 21 despite the action of the thin plate 8, and this gradually accumulates on the brush 21, shortening the life of the brush. Furthermore, when the rotation of the rotating body 2 is made faster in order to improve the cleaning effect, the rotating body 2 itself acquires the role of a fan, and the air inside the casing 3 is blown out from the intake opening. This reduces the cleaning function and also causes toner contamination within the copying device. SUMMARY OF THE INVENTION An object of the present invention is to improve a photoreceptor cleaning device as shown in FIG. 1 and to eliminate the problems associated with its installation.

Hereinafter, the present invention will be described by way of examples with reference to the drawings.

However, in order to reduce complexity, the same reference numerals as in FIG. 1 are used in FIG. 2 and subsequent figures for items with no risk of confusion. Now, the cause of the above-mentioned problems can be attributed to the insufficient amount of air necessary to transport the toner from the rotating brush.

In other words, even if the suction force of the lid 6 is considerably increased, sufficient air volume cannot be obtained at the intake port, and in order to prevent the toner that has been blown away near the intake port from scattering into the copying machine. , the intake port has to be narrowed to some extent, which causes insufficient air volume in the casing 3, and the thin plate 8 prevents toner from being removed from the brush.
Even if the phlegm is separated, there is not enough airflow to carry it away immediately, so the toner will stick to the brush again. In addition, the lack of air volume inside the casing 3
This means that air tends to stagnate inside the thing 3, and the stagnant air is blown out from the intake closing part by the fan function of the rotating body 2. Therefore, such a problem can be solved, for example, by sufficiently increasing the suction force of the fan 6, but in this case, the energy consumption by the fan 6 increases, and furthermore, the noise caused by the fan 6 also increases. FIG. 2 shows only the main parts of a photoreceptor cleaning device embodying the present invention.

The device is characterized by a rotating body 9, a surface portion of the photosensitive member 1 adjacent to the rotating body 9, and an asymmetrical casing 30 surrounding the rotating body 9.
The point is that a cross-flow fan is formed with an intake opening on the side.

That is, the rotating body 9 has brushes 92 formed on the blades of a rotor 91 for a cross-flow fan, for example, by a fur brush, and is arranged in the same manner as the rotating body 2 in FIG.

As shown in FIG. 3, the rotor 91 includes disks 911 and 912 of the same size that are arranged parallel to each other at a predetermined interval, that is, at a slightly longer distance depending on the axial length of the photoreceptor 1. Between these pair of discs 911 and 912,
Untwisted wings 91-1, 91-2, 91-3,...
・・・・・・・・・・・・,91-i,・・・・・・・
. . . are arranged parallel to each other at equal intervals along the inner edge of the circumference, and the center line in the width direction of the wing in a cross section perpendicular to the longitudinal direction of the wing is the disk 911, When the wings 912 are hung so as to intersect with the radial direction at an appropriate angle and rotated around the rotation axis 93, the wings 9
1-1, 91-2, 91
The motion areas of -i, . . . are formed in the shape of a hollow cylinder. By surrounding the rotor 91 with an asymmetrical casing and rotating it, a stable air flow across the rotor 91 can be obtained. The rotating body 9 is formed by forming brushes 92 on the blades 91i of such a rotor 91. What should be noted here is that a part of the surface of the photoreceptor 1 adjacent to the rotating body 9, together with the casing 30,
It plays the role of a casing for a once-through fan.
A filter chamber 4 is provided in connection with the exhaust port of the casing 30, and a filter 5 is provided inside the filter chamber 4 in connection with the exhaust port. The cleaning of the photoreceptor 1 by this apparatus is as follows. That is, if the rotating body 9 is driven by any known rotating means to rotate at high speed in the direction of the arrow and the fan 6 is operated, the toner remaining on the photoconductor 1 is removed by the brush 92. wiped from the surface. A portion of the toner adheres to the brush 92 and moves, and is repelled from the brush 92 by the thin plate 8. On the other hand, other parts of the toner are splashed near the surface of the photoconductor 1, but the toner that goes downwards is not scattered inside the copying machine because the end of the casing 30 is close to the surface of the photoconductor 1. First, the airflow along the surface of the rotating body 1 generated by the suction of the fan 6 and the rotation of the brush 92 transports the air to the innermost part of the casing 30 . On the other hand, as the rotating body 9 rotates, it becomes a cross-flow fan, and an air flow that crosses the rotating body 9 is formed. Therefore, the toner that has been blown away to the vicinity of the air intake opening that opens upward is carried by the air flow. , and are transported to the innermost part of the casing 30. In this way, in the case of this device, in addition to the airflow generated by the suction by the fan 6, there is also an airflow flowing through the rotating body 9, the photoreceptor 1, and the casing 3 forming the cross-flow fan.
This means that a sufficient amount of air can be obtained inside the 0, and the above-mentioned problems can be completely solved. Needless to say, in this case as well, the airflow flowing between the blades of the rotor 91 of the rotating body 9 effectively prevents the toner from re-adhering to and accumulating on the brush 92. If the efficiency of the cross-flow fan is made sufficiently large, the fan 6 becomes unnecessary.

In that case, the filter chamber 4 is also unnecessary. Even if the efficiency of the cross-flow fan is not increased significantly, the suction force of the fan 6 can be effectively reduced without reducing the cleaning effect. Furthermore, cross-flow fans generate almost no noise, so they are effective in preventing noise. However, the presence of the fan 6 is effective in improving the cleaning effect. By changing the direction of the blades of the rotor 91 and changing the direction of rotation of the rotor 91, the intake port can be opened downward. but,
Opening the intake port in the direction in which the surface of the photoreceptor 1 moves, as in this device, has the following meaning. That is, after the visible image is transferred to the recording sheet, the first
In the figure, since the photoconductor cleaning device is transported from left to right under the photoconductor cleaning device, the intake port is opened downward, that is, in the direction in which the surface of the photoconductor 1 faces. In some cases, the suction force of the cross-flow fan may cause the recording sheet to be sucked in or the visible image on the recording sheet may be disturbed, so appropriate measures must be taken to prevent this. If the opening is opened in the direction in which the surface of the photoreceptor 1 moves, such a problem will not occur. As described above, according to the present invention, the photoreceptor cleaning device for an electronic copying machine has a simple structure, can improve the life of the brush, prevents toner from scattering inside the copying machine, and has a good cleaning effect. can be provided.

Note that the shape of the rotor for the cross-flow fan is not limited to that shown in FIG. 3.

It goes without saying that the present invention is effective not only for drum-shaped photoreceptors but also for belt-shaped photoreceptors.

[Brief explanation of the drawing]

FIG. 1 is a partially sectional side view showing the diamond part of a conventionally known photoreceptor cleaning device, and FIG. 2 is a side view showing only the essential parts of an example of the photoreceptor cleaning device embodying the present invention. The partial cross-sectional side view, FIG. 3, is a perspective view showing the shape of the rotor shown at 91 in FIG. 1... Photoreceptor, 2, 9... Rotating body, 3
, 30...Casing, 4...Filter chamber, 5...
・Filter, 6...Fan, 8...Book plate, 21, 92...Brush, 91...Rotor for cross-flow fan. Figure 1 Figure 2 Figure 3

Claims (1)

[Claims] 1. A process of forming an electrostatic latent image on a photoreceptor, developing the electrostatic latent image with powder toner to obtain a visible image, and transferring the visible image onto a recording sheet. an electronic copying machine that repeats the above while moving the surface of the photoreceptor in a predetermined direction, comprising: a rotor for a once-through fan; a casing surrounding the rotor together with a surface portion of the photoreceptor adjacent to the rotor; A cross-flow fan having an intake opening on the side of the photoconductor is formed, and a filter is connected to an exhaust port of the casing of the once-through fan to capture toner in the air flowing through the fan, and the blades of the rotor A brush is formed on the body, and this is used as a rotating body, and the tip of the brush is
In the direction of the rotary axis of the rotor, the rotor is brought into contact with the surface of the photoreceptor after the visible image has been transferred onto the recording sheet at a fixed position so as to intersect with the direction of movement of this surface. A photoreceptor cleaning device for an electronic copying machine, characterized in that the device rotates in a predetermined direction. 2. A filter chamber connected to the exhaust port is provided, a filter is housed in the filter chamber, and a fan is provided near the outlet of the filter chamber for sucking air inside the casing through the filter. A photoreceptor cleaning device according to scope 1. 3. The photoreceptor in the electronic copying machine according to claim 1, wherein the air intake opening of the once-through fan opens in the direction in which the surface of the photoreceptor in the cleaning section moves. cleaning equipment.